Construction of the microbial cell factory is one of the developmental directions of current green chemical industry. The microbial cell factory is a kind of recombined microorganism and its metabolic and regulatory pathways have been reconstructed by metabolic engineering and synthetic biology to synthetic new compounds or to improve the yield of target production. The microbial metabolic pathway is regulated by two points: environment and genetic information. The cell maintains its homeostasis by global transcription factors, messenger molecules and feedback inhibition when the circumstance is changed. Meanwhile, the cell is affected by its own genetic circulate through transcription, translation and post-translational modification to regulate the expression of target gene. The riboswitches are RNA elements which change their conformation when bind to specific ligands such as ions, sugar derivatives, amino acids, nucleic acid derivatives and coenzymes to regulate the process of transcription, translation and splicing of mRNA. The riboswitches are natural biosensors and bioeffectors which can be designed as the intelligent molecular tools to fine regulate microbial cell factories. Using riboswitches in the microbial cell factory can extend the application in the field of chemical, pharmaceutical, environmental protection and food production.

Surface tension is one of the most important factors directly determining transmission capability of heat. An experimental system was improved to measure surface tension of high temperature molten liquid with pulling escape method derived from the du Noüy ring method. Instrument coefficient was calibrated with chemically pure LiNO₃. By measuring surface tensions of NaNO₃ and Solar salt (60% NaNO₃, 40% KNO₃, mass fraction), reliability of experimental system and method was validated. On this basis, four samples of quaternary bromide salts from KBr, LiBr, NaBr and CaBr₂ were made with different mass ratios. Surface tensions of samples were measured with the experimental system in the temperature range 350—500℃ and fitted as functions of temperature. The results indicate that surface tension values of quaternary bromide salts diminish linearly with increasing temperature, in accord with surface tension change of known molten liquids.

The hybrid surfaces with hydrophobic and hydrophilic regions arranged regularly and alternatively are prepared. Various widths and area fraction of the hydrophobic region are designed. The droplet properties (such as droplet drainage mode and maximum droplet radius) during steam condensation at atmospheric pressure are visualized. The motion process of condensate on hybrid surfaces is simulated by lattice Boltzmann method. The influences of the widths and surface subcooling of hydrophobic and hydrophilic region on enhancement of the steam condensation heat transfer of the hybrid surfaces are investigated. The influencing factors on the steam condensation heat transfer performance of hybrid surfaces are analyzed and calculated by hybrid condensation heat transfer model. The comparison between model and experimental results is also conducted. It is found that the droplet on the hydrophobic region can spontaneously migrate into the hydrophilic region. The dropwise condensation heat transfer of steam can be effectively enhanced by the finely designed hybrid surfaces. The enhancement factor of the heat transfer performance of the hybrid surface can approach to 1.20. When the width of the hydrophobic region is about 0.55 mm, the heat transfer performance of hybrid surface reaches the maximum. Furthermore, the effect of the heat transfer enhancement of hybrid surfaces decreases with the increase of surface subcooling. The comparison results indicate that the analytical (theoretical) results can well and conveniently predict the experimental results.

The gas engine-driven heat pump (GEHP) system is an efficient energy saving and environment-friendly heating system which consumes natural gas as fuel in a gas engine. The present work aimed at evaluating the performance of a gas engine-driven heat pump for heating. In order to achieve this objective, a test facility was developed and experiments were performed over a wide range of engine rotary speed (1300—1900 r·min^-1). The relationships of engine rotary speed, condenser water inlet temperature, condenser water flow and system performance [heating capacity, system coefficient of performance (COP) and primary energy ratio (PER)] were studied based on theoretical analysis and experimental data. The results showed that the heating capacity of GEHP increased with increasing engine rotary speed and condenser water flow rate, but decreased with the increase of condenser water inlet temperature. The COP and PER of the GEHP decreased with increasing engine rotary speed and condenser water inlet temperature. The effect of the engine rotary speed and condenser water inlet temperature on the system performance was more significant than that of condenser water flow rate. The waste heat recovered from the gas engine accounted for about 40% of the total heating capacity, and the PER of the GEHP was between 1.15—1.47 under experimental condition.

Direct contact condensation characteristics in cool water of steam jet with non-condensable gas in it were investigated experimentally in this paper. The jet plume length of the mixture gas was obtained by measuring temperature field, which was used later to get condensation heat transfer coefficient. Using a circular nozzle with a diameter of 1.6 mm, this experiment covered the range of mixture gas mass flux from 100 to 330 kg·m^-2·s^-1, non-condensable gas content from 0 to 15% and cool water temperature from 300 to 340 K. The results showed that the existence of non-condensable gas led the decrease of temperature more slowly near the nozzle exit and the increase of jet plume length with increasing content of non-condensable gas. The effect of the addition of non-condensable gas on mixture mass flux and water subcooling was the same as pure steam jet. The condensation heat transfer coefficient was found to be in the range of 0.7 and 2 MW·m^-2·K^-1, and it decreased with increasing subcooling and non-condensable gas content, while the mixture mass flux has a little effect on it. Finally, correlations predicting the jet plume length and the condensation heat transfer coefficient were obtained by fitting the experimental dates.

Traditional rigid impeller transfers energy by shearing action, while flexible-rigid impeller can intensify energy transfer by multiple-body movement. Based on the interaction between impeller and fluid, the equivalent stress and total deformation are computationally simulated for flexible-rigid and rigid impellers. Macroscopic flow structure is obtained by two-way fluid-structure interaction technique with simulation platform ANSYS Workbench, and the mixing effect in two stirred systems are discussed with measured mixing time and calculated impeller power dissipation. Compared with rigid impeller, the mixing time of flexible-rigid impeller system is decreased by 32%, its power dissipation is declined by 7%, its total deformation of blade tip is 10⁵ times larger, and its equivalent stress of blade tip is 83% greater, so that flexible-rigid impeller exerts greater force to fluid with the fluid-structure interaction, which contributes to energy transmission, liquid flow and mixing intensification.

A passive micromixer with gaps and baffles was proposed based on the principle of chaotic mixing and the fluid flow and mixing characteristics in the micromixer were studied by three-dimensional numerical simulation and visualization experiment. Expanded vortices and separated vortices were generated in the horizontal plane and counter-rotating vortices formed in the cross-sectional plane perpendicular to the flow direction by the combination of gaps and baffles. The mixing efficiency was significantly improved by the multidirectional vortices. The geometrical parameters of gaps and baffles had great effect on the fluid flow and mixing. Based on the consideration of mixing efficiency and pressure drop, the effect of gap width, gap length and baffle height on the comprehensive performance of the micromixer was investigated by the field synergy principle. The optimal structural parameters were presented with varying Reynolds number.

The intensification and mechanism of gas-liquid mass transfer in a water-sparged aerocyclone by microparticles were conducted in this paper. The effects of solid concentration c_s, gas inlet velocity u_g and liquid jet velocity u_L on specific mass transfer area a, mass transfer coefficient of liquid side k_L, volumetric mass transfer coefficient k_La and mass transfer intensification factor E were investigated by using a chemical method (CO₂-air-NaOH absorption system) and a physical method (CO₂-air-H₂O absorption system). The results indicated that the k_L, a, k_La and E increased and then decreased with the increase of solid concentration c_s, c_s has a maximum value. Solid particles could intensify mass transfer, increasing k_L, a and k_La under different u_g and u_L, whereas E decreased with the increase of u_g and u_L. The mechanism of solid particles intensifying gas-liquid mass transfer was realized through the three paths from increasing a, k_L and S, but the increase of the surface renew frequency S was the major mechanism.

In order to investigate the two-phase frictional pressure drop characteristics of boiling flows in a rectangular narrow channel under rolling motion, a series of thermal hydraulic experiments and theoretical analysis are performed. The results demonstrate that the additional inertial force is imposed on the fluid and the space of experimental loop will vary periodically under rolling motion. The fluctuation amplitude of the two-phase frictional gradient increases with increasing rolling angle and rolling period. The fluctuation amplitude and time average value of the two-phase frictional pressure gradient increase with increasing heat flux, while it decreases with the increase of system pressure. The mass flux varies with the fluctuation of frictional pressure gradient at the same period. The phase change between the fluctuation of mass flux and frictional pressure gradient is approximately equal to 1/4 rolling period due to the velocity difference of the pressure propagation and mass flux increases.

According to the thermodynamic process and the sound speed calculation models of the single/two-phase flow, a method with real gas is presented to design cylindrical mixing chamber ejectors. The entrainment ratios calculated by the proposed method match the experimental results relatively well with an error of ±17%. The proposed method predicts that there must be an optimal exit pressure of the mixing chamber corresponding to the maximum design entrainment ratio. The optimal reciprocal value of diffuser pressure ratio is introduced in order to determine the relationship between the optimal exit pressure of the mixing chamber and design conditions of ejectors conveniently and quickly. The relation curves of optimal reciprocal values of diffuser pressure ratios vs expansion and compression ratios for steam, ammonia, R290, R134a and R22 ejectors are calculated based on usual working conditions, and further the corresponding regression expressions are fitted. Those expressions can figure out the optimal reciprocal values of diffuser pressure ratios rapidly so as to obtain the optimal exit pressure of the mixing chamber, and thus a high efficient ejector can be designed.

In the present work, an integral equation approach is developed to solve the convection-diffusion equations. In this approach, Green's function of the Laplace equation in the form of series is employed to transform the convection-diffusion equation into an integral equation. With the help of orthogonal polynomials, the integral equation is reduced to an algebraic equation system with a finite number of unknown variables. Finally, this integral equation approach is examined by three examples. The Chebyshev polynomial is used to approximate the one-dimensional convection-diffusion problem with nonhomogeneous boundary conditions and the Fourier series is for the two-dimensional convection-diffusion problem with homogeneous boundary conditions. The comparisons with the finite volume method, finite element method and upwind difference method show that the integral equation approach is more accurate and stable. The stability is also proved by the convection-dominated diffusion problems. Furthermore, it can achieve a satisfactory accuracy even with a small number of grid points.

The Cu/ZnO catalysts were prepared via microchannel reactor and characterized by TEM, XRD and XPS. It was difficult to find the individual CuO or ZnO region in HRTEM picture and XPS analysis indicated that the interaction between CuO and ZnO in microchannel samples was stronger than that in classical co-precipitation samples. The results of methanol synthesis from syngas in liquid manifested that the activity of microchannel catalysts was higher than that of classical co-precipitation catalysts. Comparing the precipitation in microchannel reactor with that of classical co-precipitation, it was found that the strong turbulent and tiny space resulted in a more uniform precipitation of Cu²⁺ and Zn²⁺, intensifying the dispersion and interaction between copper and zinc. In addition, the plug flow in the microchannel reactor made Cu²⁺ and Zn²⁺ undergo more uniform reaction course and form catalysts with more homogeneous structure. The research on tube length indicated that 30 s of the residence time was needed for the Cu-Zn precursors to reach the preliminary structural stability.

(x)WO₃/TiO₂-ZrO₂ catalysts with different WO₃ content were prepared by the impregnation method and the catalytic performance for the selective catalytic reduction of NO_x with NH₃ (NH₃-SCR) was investigated in a fixed-bed stainless steel reactor. The catalysts were characterized by BET, XRD, NH₃-TPD and in situ DRIFTS analysis of NH₃ adsorption, and revealed the change of the structural property and acidic capacity. The characterization results showed that WO₃ was in a well-dispersed state and WO₃ addition enhanced the thermal stability of catalysts obviously. The adsorption and activation of NH₃ were caused by TiO₂-ZrO₂ and WO₃, respectively. It was found that W displayed a huge electronegativity and prompted the transfer of the N—H bond of NH₃ from covalent bond to ionic bond, which could incur the NH₃ activation. The results of catalytic activity indicated that the catalyst with 9%(mass) WO₃ content exhibited 94% NO conversion within the wide temperature range of 320℃ to 420℃. (9%)WO₃/TiO₂-ZrO₂ possessed comparatively higher intensity of Lewis acidity and larger amount of Brønsted acidity as well as more stable pore structure (4.4—1.7 nm). Besides, the absorption peak of the active intermediate species NH₂ was more obvious. All these characters probably accounted for its better catalytic performance.

Solid base catalysts M_nO/Al₂O₃ (M=Na, K, Cs, Mg, Ca, Sr, n=1 or 2) prepared by impregnation method and C-Cs₂O/Al₂O₃ by co-precipitation method were applied in Prins reaction. Their base amount and pK_a in water were determined. The structure and physico-chemical properties of the carrier and prepared catalysts were characterized by CO₂-TPD, X-ray diffraction, and nitrogen adsorption. The performance of catalysts was evaluated by condensation reaction of isobutene with paraformaldehyde to produce 3-methyl-3-buten-1-ol. The results showed that the performance of catalysts related directly with their basic property and structure. The C-Cs₂O/Al₂O₃ catalyst had stronger basicity and showed superior catalytic performance, and the conversion of formaldehyde and selectivity to MBO reached up to 100.0% and 86.0% respectively. The mechanism of Prins reaction over solid base catalyst was also discussed. The base sites could active the a-H of isobutene, and so could promote the Prins reaction.

Quantum chemical method based on density functional theory (DFT) was used to study the ring-open reaction mechanism of sulfur during the preparation of insoluble sulfur by gasification method. The probable reaction path was built. By the transition state theory, the activation energy and reaction rate constant were calculated for each elementary reaction. The kinetics of each elementary reaction was calculated to determine the product composition of sulfur ring-open reaction. As the result showed that the ring-open reaction of S₈ generated ·S₂· and ·S₆· preferentially, the reaction barrier was about 209.45 kJ·mol^-1. The main product of S₈ ring-open reaction were ·S₂·, ·S₄· and ·S₆·. The calculated values were in agreement with the experiment results based on steam density method. The result provided reference for the study of molecular structure and polymerization mechanism of insoluble sulfur.

A novel Pd/Al₂O₃@ZIF-8 core-shell catalyst was successfully prepared by ZnO-induced coating of a layer of ZIF-8 shell over the Pd/Al₂O₃ bead with a mean diameter of 1—2 mm. The obtained Pd/Al₂O₃@ZIF-8 core-shell catalyst was characterized by XRD, EDX, SEM and ICP analysis techniques, and employed as catalyst for the liquid-phase hydrogenation of alkenes. It was found that the introduction of ZnO layer and subsequent pretreatment of the ZnO layer played vital roles in the formation of continuous and compact ZIF-8 shell. Furthermore, the thickness of the ZIF-8 shell could be tuned by altering the assembly cycles of ZIF-8. Results of the catalytic reactions showed that the Pd/Al₂O₃@ZIF-8 catalyst exhibited better size-selectivity, poison-resistance and leaching-proof properties in contrast to the naked Pd/Al₂O₃ catalyst.

Organic peroxide is widely used for initiating free radical polymerization in unsaturated polyester copolymerization reaction, and is thermally unstable in the presence of a single oxygen-oxygen bond, which easily leads to thermal runaway accident, i.e. explosion, when exposed to an external heat source. If any contaminant, such as H⁺ or OH^－, is introduced during production, storage or transport, it may accelerate decomposition under an abnormal situation and result in deterioration. A liquid OP-tert-butyl peroxy benzoate (TBPB) was chosen to mix with NaOH and H₂SO₄ to examine H⁺ or OH^－ effects on its thermal hazard using an adiabatic accelerating rate calorimeter. The progresses in thermal decomposition of pure TBPB and mixtures with small amount of NaOH and H₂SO₄ are tracked using single “heat-wait-seek” operation mode and “isothermal age” plus “heat-wait-seek” mode, respectively. In order to characterize the effect of H⁺ and OH^－ on TBPB thermal hazard, the parameters of reaction kinetics and their corrected values with thermal inertia factor are determined from their characteristic parameters of thermal decomposition with pseudo inverse matrix method by least square method under the worst condition, and they are the characteristics of intrinsic thermal hazard of TBPB. The time to maximum heating rate (TMR) is predicted by Townsend equation involving reaction mechanism and reactant concentration. Based on the kinetic parameters and Semenov thermal explosion theory, the thermal hazard parameters, such as self accelerating decomposition temperature (SADT), CT, and ET, can be calculated, which are crucial for application in industry. A comparison of the mixtures to pure TBPB shows two exothermic peaks for mixture of TBPB and OH^－. The first is at 60—70℃ and is characterized by very low heating rate and temperature rise, so that reaction heat is not sufficient to sustain the thermal runaway reaction, resulting in higher initial exothermic temperature and reaction kinetic parameters in the second exothermic stage, i.e. main exothermic stage. In contrast, without two peaks for the mixture of TBPB and H⁺, this mixture has lower reaction kinetic parameters, increasing reactivity and thermal hazard. The TMR and SADT data obtained by calculation indicate that the addition of H⁺ contaminant causes appropriately lower warning temperature. When 30 L high density polyethylene barrel packaging is adopted, the SADT of TBPB contaminated by H⁺falls from 65.9 to 62.6℃, indicating that strict temperature control measures are necessary.

The ZSM-5 zeolites with nano, submicron and micron crystal size, denoted as N-ZSM-5, S-ZSM-5 and M-ZSM-5, respectively, were synthesized via hydrothermal method. The effect of crystal size on the product selectivity in catalytic cracking of n-heptane to light olefins reaction was also studied at 510℃ and 650℃,respectively. The results showed that the crystal size of ZSM-5 zeolites had little effect on the n-heptane conversion and the selectivity to olefins at the initial phase at the above two temperatures. At 510℃, however, the submicron and nanometer ZSM-5 zeolites exhibited higher and almost similar selectivity to olefins and stability of reaction activity than the micron sample along with the reaction time. Nevertheless, the N-ZSM-5 zeolite displayed the best performance of selectivity to olefins and stability of reaction activity at 650℃ due to the short diffusion path length and the large external surface area compared to the S-ZSM-5 and M-ZSM-5. The micron-sized M-ZSM-5 zeolite presented the relatively higher selectivity to olefins than the other zeolites, but it also owned the lowest stability of reaction activity at both temperatures. In the catalytic cracking reaction of F-T naphtha, the S-ZSM-5 zeolite gave the best performance of selectivity to olefins and the stability of reaction activity and it may attribute to the complex components of the naphtha materials and their various reaction paths to olefins.

The oxidation efficiency of H₂O₂/O₃ catalyzed by titanium dioxide (TiO₂) for acetic acid (HAc) degradation, a probe compound for hydroxyl radical in ozonation, was investigated, with a focus on the effect of TiO₂ crystal phase. The results indicated that the addition of TiO₂ showed negative effect on the oxidation efficiency when the initial pH was at 7.0 and 10.0, and among all crystal phases of TiO₂ anatase had the biggest negative effect. However, when the initial pH was at 3.0, rutile could significantly improve the oxidation efficiency of the H₂O₂/O₃ system, and anatase had negligible effect. The mechanism study showed that there existed a good correlation between degradation rate of HAc and concentration of H₂O₂ (or its decomposition rate). Both anatase and rutile could accelerate decomposition of H₂O₂ at initial pH of 7.0 and 10.0, and faster was for the former than the latter. Too high decomposition rate of H₂O₂ could reduce removal rate of HAc at the two pH, because the conjugate base HO₂^- of H₂O₂ generated could react with ozone to effectively produce hydroxyl radicals (·OH). At initial pH 3.0, the oxidation efficiency of H₂O₂/O₃ system was very low due to the difficulty of H₂O₂ deprotonation, so the concentration of H₂O₂ had almost no change. Addition of TiO₂ could markedly accelerate the decomposition rate of H₂O₂, including deprotonation step, and anatase made H₂O₂ decomposition finish in 5 min and too fast, leading to have no effect on the oxidation efficiency. However, rutile had no such high decomposition rate for H₂O₂ and could generate HO₂^- -similar species which could react with ozone to produce hydroxyl radicals (·OH) to degrade acetic acid. The batch test carried out also gave a similar result. Therefore, it can be concluded that suitable initiator and its concentration may play an important role in ozone-based advanced oxidation process, and that too high concentration of initiator might lead to rapid consumption of oxidants. The amounts of superoxide ion radical (·O₂^-) in H₂O₂/O₃, anatase TiO₂/H₂O₂/O₃ and rutile TiO₂/H₂O₂/O₃ systems were determined by capturing method of Nitro Blue Tetrazolium Chloride (NBT), the order was as follows: H₂O₂/O₃< rutile TiO₂/H₂O₂/O₃< anatase TiO₂/H₂O₂/O₃, which was in accord with the results of the results of HAc degradation.

The physical and chemical properties of the activated carbon have an important influence on the performance of carbon based catalysts for the dehydrochlorination reaction of tetrachloroethane(TeCA) to trichloroethylene (TCE). Activated carbons were pretreated by the use of acid or alkali solution. The surface oxygen-containing groups, physical structure, and the types and content of inorganic oxides of untreated and pretreated activated carbons were characterized by XRF, BET and Boehm titration. The physical structure and high boiling organic residues of the used activated carbon samples were obtained with the help of BET and GC-MS. The performances of different treated activated carbon samples for the reaction of TeCA to TCE were investigated. Furthermore, deactivation mechanism was discussed by the association of these physical and chemical properties and the stability of the activated carbon samples. The results showed that the treatments brought major change to the type and content of inorganic oxides rather than oxygen-containing groups and physical structure. The specific surface area and pore volume of the used carbon samples decreased with the generated 1,1,2,4,4-pentachlorobuta-1,3-diene. The main factor on the stability of activated carbon samples was not the surface oxygenic groups, but the Al and Fe. Water and Lewis acid like AlCl₃ and FeCl₃ were generated from the reaction of Al (Fe) oxides and by-product HCl. Under the effect of the Lewis acid,tetrachloroethane or trichloroethylene accelerates the formation of carbocation intermediate. Then, carbocation was polymerized with trichloroethene and undergone dehydrochlorination to give 1,1,2,4,4-pentachlorobuta-1,3-diene (1,1,2,3,4-pentachlorobuta-1,3-diene), even other polymerizations with longer molecular chains. These polymers were accumulated in the hole of activated carbon, leading to the decrease of the specific surface area and then the deactivation of the catalyst.

A series of Me-OMS-1s (Me=Mg, Co, Ni, Cu) molecular sieves was synthesized by the static hydrothermal method. The as-synthesized Me-OMS-1s were characterized by means of XRD and AES-ICP. The effects of reaction temperature (318—338 K), reaction time (0.5—6 h) and formal catalyst concentration (1.67—8.33 mg·ml^-1) were investigated in detail on catalytic decomposition of tert-butyl hydroperoxide into tert-butyl alcohol over the as-synthesized Me-OMS-1s. The results showed that the synthetic Me-OMS-1s belonged to todorokite-type manganese oxides. All the Me-OMS-1 catalysts bore the activity for the catalytic disproportionation decomposition of tert-butyl hydroperoxide under the selected heterogeneous catalytic reaction conditions. The conversion of the reactant tert-butyl hydroperoxide under various reaction conditions was found to be high and the selectivity towards the product tert-butyl alcohol was 100%. The activity of Me-OMS-1s followed the order of: Cu-OMS-1 > Mg-OMS-1 > Ni-OMS-1 > Co-OMS-1. The conversion level of tert-butyl hydroperoxide was markedly enhanced with increasing reaction temperature, contact time and formal Me-OMS-1 concentration.

The dissolution kinetics and behavior of cobalt extraction from low nickel matte converter slag by pressure oxidative leaching with sulfuric acid were investigated. The effects of stirring speed, temperature, sulfuric acid concentration, oxygen partial pressure and particle size on extraction rate of cobalt were studied for exploring the kinetics law of cobalt dissolution from the slag. The experimental results showed that the extraction efficiency of cobalt increased with the increases of temperature, sulfuric acid concentration and oxygen partial pressure, but the sulfuric acid concentration above 40 g·L^-1 can cause an increase of iron extensive dissolving in the solution. The stirring speeding above 700 r·min^-1, oxygen partial pressure beyond 650 kPa and particle size of less than 74 mm were found to have no effect on the extraction of cobalt. The dissolution kinetics analysis of the experimental data based on the shrinking core model for various conditions indicated that the reaction rate of leaching was mainly controlled by the chemical reaction during its early stages, then switched to be controlled by mixed chemical-reaction and product-layer diffusion, and finally was controlled solely by diffusion through a surface product layer in the later stage. The activation energy was calculated to be 43.19 kJ·mol^{-1 in the early surface chemical reaction controlled stage and 10.49} kJ·mol^{-1 in the later diffusion controlled stage, respectively. In the chemical reaction controlled stage, the reaction orders with respect to sulfuric acid concentration, oxygen partial pressure and particle size are 0.79, 0.85} and -0.95, respectively.

To improve the performance of CO₂ separation membrane, MCM-41 modified by amines (MCM-NH₂) was filled into polyvinylamine (PVAm) aqueous solution to fabricate PVAm-MCM-NH₂ coating solutions. PVAm-MCM-NH₂/polysulfone (PSf) mixed matrix composite membranes were prepared by coating PVAm-MCM-NH₂ solutions on PSf ultrafiltration membranes. The separation layer of the composite membrane was very thin, which benefited the improvement of CO₂ permeance. The amine groups grafted to MCM-41 facilitated the transport of CO₂ through reversible reaction and simultaneously improved the filler-polymer interface compatibility. The separation performance of PVAm-MCM-NH₂/PSf membranes with different MCM-NH₂ content was tested using CO₂/N₂ mixed gas (15% (vol) CO₂ + 85%(vol) N₂). When m_MCM-NH2/m_PVAm in the coating solution was 0.2 at testing temperature of 22℃ and feed gas pressure of 0.11 MPa, the composite membrane exhibited a CO₂ permeance of 4.66×10^-7 mol·m^-2·s^-1·Pa^-1 and a CO₂/N₂ selectivity of 150. The high-performance PVAm-MCM-NH₂/PSf membrane showed promising applications in CO₂ capture from flue gas. Moreover, the effects of the wet coating thickness, the heat treatment and the introduction of the small molecule amines on the separation performance of PVAm-MCM-NH₂/PSf membrane were investigated. The results indicated that the increase of wet coating thickness (from 50 μm to 100 μm) with heat treatment under 80℃ or the introduction of ethanediamine would lead to the improvement of the pressure stability, but the loss of CO₂/N₂ separation performance under low pressures.

A series of sponge-like polysulfone substrates were fabricated by adjusting the content of PSf and water in the casting solutions. Then, the polyamide reverse osmosis composite membranes were prepared via interfacial polymerization between m-phenylenediamine and trimethyl chloride over the polysulfone substrates. The resulting substrates and reverse osmosis membranes were characterized to investigate the influence of the polysulfone concentration on the substrates properties and the effect of the substrates properties on the polyamide reverse osmosis membranes. The results showed that with increasing PSf concentration, the average surface pore size and porosity of the substrates decreased, and the resistance ability to compaction enhanced. Besides, the reverse osmosis composite membranes prepared by using different PSf substrates showed different flux and salt rejection. Considering the properties of the substrates and the polyamide reverse osmosis composite membranes, sponge-like substrate by using 15%(mass) polysulfone concentration was suitable for the preparation of reverse osmosis composite membrane.

A new air gap membrane distillation module based on hollow fiber with energy recovery was developed for desalination using 70 g·L^-1 NaCl solution as the feed. The effects of membrane module length and membrane pore size were investigated. For measuring directly the effects of operating conditions, membrane module properties, and temperature and concentration polarization on the mass transfer coefficient, the total mass transfer coefficient was introduced. The effects of membrane pore size, feeding temperature and feeding flow rate were studied. The results showed that the total mass transfer coefficient increased with the increase of membrane pore size and feeding temperature. The membrane flux and gained-out put ratio were increased effectively with increasing membrane pore size. Since increasing membrane module length would reduce the membrane flux while enhance the gained-out put ratio, the membrane flux and gained-out put ratio should be considered comprehensively for selection of the appropriate membrane module length in the application process.

Distiller waste produced in ammonia-soda process restricts the development of soda industry. In this study, the polymorph transformation and crystallization mechanism of calcium carbonate in the reactive extraction-crystallization coupled process were investigated. The results show that carbon dioxide (CO₂) is first absorbed by the organic phase and then transferred to the aqueous phase. Calcium bicarbonate is generated and then decomposed into amorphous calcium carbonate rapidly. Temperature has a significant effect on the polymorph of calcium carbonate. Needle-like aragonite forms preferentially at higher temperatures and spherical and flower-like vaterite forms preferentially at lower temperatures. Both of them will finally transform into rhombic calcite by dissolution and recrystallization. At 20℃, the formation of new vaterite and its transformation to calcite occur simultaneously in the coupled process. The content of vaterite in the particles increases with the increase of CO₂ concentration.

Low-volatility organic acids are harmful to the environment. Adsorption/desorption study of organic acids on adsorbents is of great significance to control these pollutants. Here temperature programmed desorption method was used to study the desorption behavior of ethanedioic and benzoic acids on activated carbon. Results show that textural characteristics of activated carbon play a critical role since wide micropores (0.7—2 nm) and narrow micropores (<0.7 nm) dominate the adsorption at active sites Ⅰ and Ⅱ, respectively. Interactions of ethanedioic and benzoic acids with active site Ⅰ (E_d = 101.63, 112.43 kJ·mol^-1) are weaker than those with active site Ⅱ (E_d =118.01, 130.87 kJ·mol^-1), whereas the adsorption amount on active site Ⅰ is much larger than that on active site Ⅱ. Molecular sieving effect is shown to explain the fact that ethanedioic acid with a chain structure and smaller kinetic diameter is easier to be adsorbed into narrow micropores as compared to benzoic acid with a circular structure and larger kinetic diameter.

Under various conditions, the adsorption capacity of metal-organic framework, MIL-101(Cr), was measured for cationic dyes (methylene blue (MB), rhodamine B) and anionic dyes (helianthine B (HB), acid chrome blue K) in aqueous solutions. The effect of various factors on the adsorption selectivity of MIL-101(Cr) was studied for HB and MB in mixed solutions. The results show that the adsorption capacity to anionic dyes is higher than that to cationic dyes when the dyes exist solely or coexist. The selection coefficient b is 5.9 at T=300 K and pH=3, and it decreases obviously with the increase of pH value, while temperature has a little effect on adsorption selectivity. The mechanism for adsorption selectivity is that MIL-101(Cr) has positive surface potential, so there exist electrostatic attractive interactions between MIL-101(Cr) and anionic dye molecules while it is repulsion interaction for cationic dyes. Moreover, modification with ethyl diamine increases the adsorption selectivity of MIL-101(Cr) for anionic dyes, whereas with oxalic acid the selectivity decreases.

In order to resolve the problem of controling the vapour split in the divided wall column (DWC), a new vapour splitter was put forward. The study was carried out by using the computational fluid dynamics (CFD) software STAR-CCM+ with k-ε turbulence model and SIMPLE method. The split and the nonuniformity of the vapour were researched and compared against experimental data. The relationship between vapour tubes and internal diameter of the column was examined by simulations. Model results and experimental data obtained in this study have revealed that the device can accurately adjust the vapour split and achieve a uniform vapour distribution. The model results were in good agreement with experimental data.

An advanced technology integrating a high-temperature distillation column with low-temperature side reactors(SRC) was proposed for tert-butyl acetate production via the additive esterification of acetic acid and isobutylene, since the reaction and separation required completely different operations. With a vapor boilup rate of 100 kmol·h^-1, acetic acid conversion of 99.9% and tert-butyl acetate selectivity of 97.0%, the effects of flow rate from distillation column to reactors, stage number of rectification zone, side-reactor number and interval stage number between inlet and outlet of the reactor were systemically investigated. The results demonstrated that a higher economy process could be achieved with a more optimized match between the reaction capability and the separation capability. The obtained results laid a foundation for design and optimization of the industrial SRC process.

Under ideal operation conditions, the calculation for total evaporation and the minimum total evaporation of binary stripping batch distillation under optimal operations is a constrained function optimization problem. In this work, the constrained function optimization problem is transformed to an unconstrained function optimization problem based on the penalty function method and the fixed double step length factor gradient method is used to solve the unconstrained optimization problem. The calculations show that the fixed double step length factor gradient method has good convergence, and the effect of numerical truncation error accumulation on the calculation results is reduced when the number of segments is large. The energy consumption of binary stripping batch distillation under optimal operation is lower than that under constant residual fraction composition operation. It may be attributed to the following reasons: when the theoretical plate number is relatively small (close to the minimum theoretical plate number required for binary stripping batch distillation under constant residual fraction composition operation), the energy efficiency is improved because of controllable reboil ratio under the optimal operation; when the theoretical plate number is relatively large, the entropy generation in liquid mixing in the top tank is reduced because the material is removed out of the distillation system as soon as possible in the premise of relatively high energy efficiency under the optimal operation because of the controllable reboil ratio. Under ideal operating conditions and infinite number of theoretical plates, the change strategy of the reboil ratio and the calculation formula of the minimum total evaporation of binary stripping batch distillation under optimal operation are obtained by summarizing and extrapolating the above calculation results.

The decentralized down-comer sieve plate column, a novel plate column, was designed and invented on the basis of the sieve plate column. The segmental down-comer of the traditional sieve plate column was changed into multiple down-comers that evenly distributed among the sieve pores. The new structure made the entire plate into mass transfer zone (MTZ) for well-distributed liquid drop and receiving, and it produced a new shower and splashing mass transfer area. Thus, it realized three-dimensional, continuously differential contact and mass transfer process for gas and liquid. In addition, packing or catalysts can be installed between the adjacent plates to strength mass transfer and promote chemical reactions in the tower. Adopting oxygen-air-water system, the mass transfer characteristics and influencing factors of the efficiency of the new plate were explored and compared with the traditional plate. The results showed that the gas and liquid in the new sieve column were distributed evenly and contacted adequately, and the mass transfer efficiency was higher than that of the traditional sieve plate by 8.4%—9.7% in the same conditions.

Cracking furnace is the key equipment in petrochemical industry. Optimization of cracking furnace status is very important to enhance benefits of ethylene plant. Since pyrolysis reaction mechanism is complex, the model of cracking furnace is difficult to obtain and the cracking furnace has frequent disturbances, and thus it is difficult to optimize the cracking furnace status with traditional optimal methods. In order to solve the problem that the model of cracking furnace is needed in its optimization and the traditional optimal methods lack adaptivity and anti-interference, the correlation integral optimal method is proposed in this paper. First, the operating parameters affecting the benefits of cracking furnace are analyzed, the appropriate operating variables are selected and the optimal objective function is constructed. Then, the historical database is established via the data of operating variables and optimal objective function. Finally, the cracking furnace status is optimized based on the iteration of correlation integral optimal method. The simulation results verify the effectiveness of the correlation integral optimal methods in cracking furnace optimization.

In recent years, model-free adaptive control (MFAC) harvests a rapid development because it does not require the mathematical model and only uses the input/output data of the controlled system. In this paper the Quasi-Newton Methods (BFGS) was used to revamp the parameter input of MFAC of MIMO systems, resulting in less iterative calculating number of times and adjusting time. The application in a gas fractionation unit with an annual processing capacity of 0.3 Mt showed that MFAC can reach propylene quality target and steady operation rapidly with less energy consumption due to the minimum heating and cooling duties when facing operation fluctuation.

Nuisance alarms are recognized as the major problem in the process industry. However, current alarm optimization methods usually suffer difficulties such as low sensitivity and poor reliability. In this paper, based on alarm interval and alarm duration of alarm data, the types of nuisance alarms are determined before an adaptive method to effectively determine the delay timers and alarm deadbands. An ARMA model is established to forecast adaptive alarm deadbands which are employed to deal with high frequency alarms, while the alarm delays updated by adaptively adjusting alarm time intervals are used to deal with low frequency alarms. Experiments with industrial process data are carried out, illustrating that the proposed method can reduce the numbers of false and missed alarms as well as improve the performance of alarm systems.

Membrane fouling is a key factor for the increase of operation cost and the decrease of product performance of the seawater reverse osmosis (SWRO) system. In this work, a strategy of new membrane cleaning and replacing schedule for spiral-wound SWRO system was proposed to reduce the operation cost. First, according to the solution-diffusion principle and membrane fouling characteristics, the SWRO performance model considering membrane fouling was established. Then, the total operation cost was integrated with membrane cleaning and replacing schedule to establish the optimization problem, which set minimizing the daily operation cost of the system as an objective, membrane cleaning frequency, cleaning time and replacing time as optimization variables, and the open equations as constraints. And the finite-element-based simultaneous method was applied to solve the complex optimization problem efficiently. After the case study and analysis of the SWRO system, the optimization results showed that the proposed optimization strategy can significantly reduce the operational cost, while obtaining the optimal membrane cleaning frequency and the cleaning and replacing time. It was found that the feed seawater temperature had an important effect on the membrane cleaning and replacing schedule as well as total operational cost, and thus it was not suitable to fix the membrane replacement interval. In addition, the proposed method can obtain the profile of optimal operational pressure and flow rate as well as internal status and performance of the system under different operation conditions, which was of great significance to optimize the operation of the system and the further study on the inner status of the system.

Principal component analysis (P monitoring CA) is a classical algorithm for feature extraction and has been widely used in multivariate statistical process. The essence of the PCA algorithm is to extract the correlation between process variables. However, the correlation matrix defined in the traditional PCA algorithm is limited to consider the linear relationship between variables, which cannot be employed to analyze the mutual dependence between two measured variables. With recognition of this lack, a novel mutual information based PCA (MIPCA) method is proposed for process monitoring. Distinct from the traditional PCA, MIPCA defines the relationship between variables by calculating the mutual information, and the original correlation matrix is replaced by the resulting mutual information matrix. The eigenvectors of the mutual information matrix can thus be utilized as the directions of feature extraction. On the basis of MIPCA, a statistical process monitoring model can then be constructed. Finally, the feasibility and effectiveness of the MIPCA-based monitoring method are validated by a well-known chemical process.

The concentration of biologic surface active materials has a great influence on the foam properties of the solution with them. Foam properties include foaming ability and foam stability. In this work, foaming ability and foam stability were characterized by initial foam height and half-time of foam, respectively. The relational expression between the initial foam height of the solution with two surface active materials and their concentration bellow the critical micelle concentration (CMC) was determined by using the extended Szyszkowski equation and Rosen's empirical model. The relational expression between the half-time of foam of the solution with two surface active materials and their concentration bellow the CMC was established on the basis of the rules that the gravitational potential energy and the surface energy all decreased with the bubble breakup in the foam phase. An aqueous solution with bovine serum albumin (BSA) and lysozyme (LZM) was used as the simulation system to verify the accuracy of these relational expressions. The results showed that the two relational expressions could be used to accurately predict the foam properties of the solution with BSA and LZM. The effect of BSA on the foam properties of the solution was more significant than that of LZM.

As a new type of modern manufacturing technologies, micro-fabrication technology comes into being with the emergence of micro-manufacturing, which realizes the machining and assembly in micro size. The chemical etching technology is one of the major processing methods for micro-fabrication technology, which includes immersing, bubbling, spraying and so on. Among them the equipment of immersion etching is simple, easy to operate and relatively low-cost. In this study, the influence of etching time, concentration of the etching liquid composition, etching temperature and other factors on the chemical etching is mainly studied by using single factor immersion method. The results show that FeCl₃ concentration, H₃PO₄ concentration in the etching liquid, etching temperature and others heavily affected the etching rate, etching uniformity, lateral erosion and surface roughness. It provides elementary process parameters for the micro-manufacturing.

It is inevitable for the soot particles from engine fuel to contaminate the lubricating oil, which may increase the viscosity of lubricating oil, and consequently influence the lubricity and usability of engine. In this paper, the surface properties of biomass fuel soot (BS) and diesel soot (DS) were contrastively investigated by means of Fourier infrared spectrometer, X-ray photoelectron spectroscopy, full-automatic micropore physisorption and chemisorption analyzer, optical contact angle/interface tension meter and Zeta potentiostat in order to study the effect of BS and DS particles on viscosity of liquid paraffin (LP, simulant of base oil for lubricating oil), and discuss the mechanism of influence of soot surface properties on the viscosity. Results showed that the relative viscosity increased by exponential function with increasing soot content at 40℃. The relative viscosity of oil contaminated by DS was higher than that of BS in case of the same soot contents. The oil contaminated with high concentration soot had the advantage of clearly identified shear thinning behavior, which was more severely in LP contaminated by DS. The main surface elements of BS and DS were carbon and oxygen. The surface oxygen content of DS was less than that of BS. There were some O-containing functional groups on the surfaces of BS and DS. The surface property analysis showed that the specific surface area and the surface energy of DS were higher than those of BS. The lipophilicity of DS was less than that of BS. The DS was apt to agglomerate into larger agglomeration particles in LP, which was the main reason for the fact of DS affecting LP viscosity more severely compared with BS.

The MHZSM-5(M=Fe, Zr and Co) zeolite catalysts prepared by impregnation method were characterized using laser particle size analyzer, specific surface area and pore size analyzer and X-ray diffraction (XRD), and applied for on-line cracking vapors from cellulose fast pyrolysis with vertical two-stages furnace. The bio-oils obtained by direct liquefaction with and without catalysts were characterized by GC-MS analyses. The results indicated that with introduction of catalysts, liquid yield decreased from 52.06% to 23.63%, while gas yield increased up to 70.84% from 42.39%; and CoHZSM-5 showed the most obvious effect for catalytic pyrolysis. The component of bio-oil from fast pyrolysis of cellulose was mainly 1,6-dehydration-β-D-glucopyranose (levoglucosan). After the addition of catalysts to online catalytically reform vapors of cellulose fast pyrolysis, the contents of aromatics increased significantly in the product, and FeHZSM-5 and ZrHZSM-5 had the best effect. The content of levoglucosan was increased to 63.78% for HZSM-5 catalyst. The contents of acetic acid and propionic acid were reduced slightly by catalytic pyrolysis. Based on the balance of the yield and composition of bio-oil, it was considered that FeHZSM-5 and ZrHZSM-5 played more significant role during cellulose fast pyrolysis.

The composition of biomass pyrolysis vapors is complex. Their separation properties were investigated by using fractional condensation under different temperature. According to the distinct dew points of the compound containing, the enrichments with different bio-oil grouping were produced by controlling condensed temperature such as 300℃, 100℃, 0℃ and -20℃, and so four groups of bio-oil samples were obtained during our experiment of fractional condensation and their characteristics of each fraction were studied and analyzed. The yield of liquid condensed in 0℃ is the highest and more than 50% of the whole bio-oil, while that did in 100℃ contained the organics with molecular weight of 80 to 200, mainly fusel phenol compounds. The fraction collected in 300℃ was bitumen, which did not contain moisture, look like solid carbon and there was no liquidity and viscosity. Water and organic acids had well be separated from bio-oil in fractional condensation, more than 80% water and nearly all the organic acids were collected in the enrichments at 0℃ and -20℃. The distribution of some typical components including acetic acid, phenols, guaiacol, and PAH under different condensed temperature was analyzed by GC-MS, and enrichment rule was obtained based on behaviors of typical compounds condensing in bio-oil.

Chemical conditioning is commonly used before the mechanically dewatering process for sewage sludge. The flow field distribution of conditioning tank has a significant effect on conditioning when paddles are operating. Moving reference frame-volume of fluid model was used for simulating flow field distribution of a sludge conditioning tank with the inner diameter of 40 cm by CFD (computational fluid dynamics) technology, and the gas-liquid two-phase distribution was verified. The results showed that in the single straight blade paddle conditioning tank, the optimium ratio of paddle diameter to tank diameter was 1:1.75 and the optimum ratio of baffle width to tank diameter was 1:20. Under these optimum conditions, the fluid swirl could be effectively eliminated and the turbulent action could be enhanced. Furthermore, the flow field distribution simulation was conducted for pilot-scale conditioning tank with the inner diameter of 110 cm and the simulation results were compared with test results. Moving reference frame-volume of fluid model used in this study can provide references for design and optimization of similar sludge conditioning tank.

In order to investigate characteristics of volatile contaminant release and migration during CO₂ geological sequestration, a contaminant migration model with multiphase displacement process in a CO₂-aqueous phase-residual oil phase system was proposed. Numerical simulations were performed to figure out the multiphase displacement and the contaminant migration, and further to explore the effects of interphase mass transfer, initial profiles of the residual oil and injection rates on the volatile contaminant migration. The results indicate that the volatile contaminant enters into the supercritical CO₂ phase due to the multiphase displacement process, and migrates with the mobile phase in the subsurface formation. An interphase mass transfer region (IMTR) gradually forms. The evolution of IMTR directly reflects the release characteristics of contaminant and migration behaviors of CO₂ coerced with contaminant. A larger interphase mass transfer coefficient results in a narrower IMTR and a faster decay rate of the oil phase. When the initial saturation of the oil phase is larger, the IMTR becomes much narrower and the oil phase decays much slower. With increasing CO₂ injection rate, IMTR increases and the oil phase decays rapidly. The proposed model and the results intuitively describe the migration characteristics of the volatile contaminants in a variety of geological reservoirs during CO₂ geological sequestration. The proposed model can also be used for the risk analysis and evaluations of CO₂ storage.

The DBU/C₃-alcohol/CO₂ ionic compounds were synthesized by reacting the C₃-alcohols, namely 1-propanol, 2-propanol, 1,2-propanediol, 1,3-propanediol and glycerol with CO₂ and 1,8-diazabicycloundec-7-ene (DBU), respectively. The composition and structure of them were characterized by FT-IR, NMR and TG. The reactivity of the hydroxyls at different position in C₃-alcohol and the steric effect in polyols were studied. The results showed that the reactivity of the primary hydroxyl of 1-propanol was higher than the secondary hydroxyl of 2-propanol in the reaction of DBU+C₃-alcohol+CO₂. For the diols, the steric hindrance and the electronic effect significantly lowered the activity of the second hydroxyl, and such interaction in 1,2-diols was stronger than that of 1,3-diols. For the DBU+glycerol+CO₂ system, the main ionic compound was formed by reacting with only one of the primary hydroxyl in glycerol. The second most abundant product was formed by reacting both of the primary hydroxyls in glycerol. However, the complete conversion of all three hydroxyls seemed not possible due to the high steric hindrance effect.

In order to identify the function between the distribution pattern of steam coal content and ignition and stable combustion characteristics, a mathematical analyzing data test is made to 166 coal qualities used by pulverized-coal fired boiler of large power station in China. This research analyzed the distribution pattern of V_daf ratio between fixed carbon (C_gt) and equivalent gaseous carbon (C_qt 3.67H_ar), and its influence on the ignition and combustion characteristics. With the experimental data from one dimension sedimentation furnace of 77 coals collected from the literatures, the function of ignition temperature to V_ad and A_ad was simulated, and the distribution characteristics of ignition temperature and heat of different coal samples were calculated and analyzed. A new method for resolving images of ignition temperature and heat was introduced, which has been applied to analyze the characteristics of coal firing. The results showed that it can not only quantitatively distinguish the ignition characteristics among the same and different type of coals, but also give reasonable explanation of macroscopic law in theory.

Polyhydroxybutyrate (PHB) production by halophilic mixed consortia draws a lot of attention because of its great advantages, such as no sterilization, extraction convenience and high production. In this study, halophilic mixed microbial cultures were used to investigate the influence of adjusting modes of the organic loading rate on PHB production. Two adjusting modes were applied including adjusting sludge concentration with a consistent substrate concentration and substrate concentration with a consistent sludge concentration. The maximum PHB content in cells, maximum PHB volumetric yield and kinetics were compared to confirm the optimum OLR and the key difference in the two modes. The experimental results showed that the high OLR led to a high PHB content in cells and a high PHB volumetric yield. In this study, 0.91 kg ·(kg ·d)^-1 was proved to be the optimum OLR for halophilic MMCs. On condition of identical OLR, the high sludge concentration led to high carbon source conversion ratio and substrate consumption rate. Then, a high sludge concentration can enhance PHB productivity and depress PHB production cost.

An experimental prototype of organic Rankine cycle (ORC) was built for low-temperature waste heat power generation. With R123 as working fluid, heat transfer oil as the waste heat source, and radial inflow turbine as expander, a series of tests were carried out by adjusting the R123 mass flow rate to evaluate the performance of apparatus and system. The temperature rise and entropy increase of hydraulic diaphragm pump were lower, and consumed power increased with the mass flow rate. The pressure drop in the evaporator was greater than that in the condenser, and both increased with the mass flow rate of R123. The isentropic efficiency of the radial inflow turbine increased first and then decreased with the increase of R123 flow rate, with the maximum value of 0.775 kg·s^-1 and the optimum value of 0.215 kg·s^-1. The system output power increased monotonously to 2.009 kW as the flow rate of R123 increased to 0.283 kg·s^-1. Exergy destruction rate of evaporator was the largest parts in total exergy destruction rate, followed by condenser and radial inflow turbine, about 62%, 32% and 6%, respectively, under the optimum condition.

Dewatering and upgrading of Inner Mongolia Xilingol lignite in non-polar solvent (tetrahydronaphthalene, THN) were carried out in a miniature autoclave. The changes of organic functional groups in coal samples at different dewatering temperature were analyzed based on Fourier-transform infrared (FT-IR) analyzer. The fitting calculation for FT-IR spectra has been carried out. Besides, a semi-quantitative analysis for characteristics of chemical structure change was presented. The pyrolysis and gasification reactivity and distributive rules of gas phase product during pyrolysis and gasification of coal with various dewatering temperature were carried out by means of thermogravimetric analysis (TG) and a bench-scale fixed-bed pyrolysis reactor. The kinetic parameters of coal samples were calculated within the range of the maximum weight loss rate. The results showed that the non-polar solvent THN treatment was effective in dewatering and upgrading of Xilingol lignite. The C O bonds started decomposing between 150 and 200℃, while the aromatic C C bonds in the aromatic ring remained relatively stable. With increasing dewatering temperature, the content of aromatic hydrogen decreased first and then increased, while the content of aliphatic hydrogen increased first and then decreased. The aromaticity and aromatic carbon increased gradually with increasing dewatering temperature. When dewatering temperature was higher, the cumulative yields of gas phase products of H₂, CH₄ and CO were increased and CO₂ was dropped during pyrolysis. The reaction activation energy of the dewatered coal increased with increasing dewatering temperature, decreasing the pyrolysis reactivity of the coal samples.

Comb-like polycarboxylate dispersants (PC) with different side chain lengths ranging from 8—23 nm were synthesized using esterifiedmacromer of methoxypolyethyleneglycol (MPEG)-acrylic acid (AA), AA and styrene sulfonic sodium (SSS). The molecular structure of PC was analyzed by testing its anionic group content and relative molecular. Experiments were performed to study the influence of the length of PC side chain on dispersion and rheological properties of coal water slurry (CWS). The adsorption behaviors of PC on coal/water interface were analyzed by X-Ray photoelectron spectroscopy (XPS), which was combined with the Zeta potential and the wettability of PC on coal to investigate the action mechanism of PC dispersions in order to provide the basis for designing more efficient polycarboxylate dispersants. The results showed that the dispersibility of PC500 (n=11) was the best due to its structure of long main chain, short side chains and high anionic group content. The CWS using comb-like PC was represented as pseudoplastic fluid, which was best matched with Herschel-Bulkley model. The monolayer adsorption of PC500 on the coal surface possessed the highest adsorption density (0.638 mg·m^-2) as well as the maximum thickness (4.20 nm) with better wettability and the highest Zeta potential on coal. PC500 wearing the proper length of the side chain played the steric hindrance and electrostatic repulsion to disperse CWS by balancing adsorption thickness and Zeta potential. PC500 with the right length of the side chain can reduce Gibbs of CWS to weaken “reunion” among the coal particles while improving dispersibility of CWS.

Fans are used for cooling and feeding oxygen in air-cooling proton exchange membrane fuel cell (PEMFC). For optimal performance, it is essential that the air is distributed as uniformly as possible and supplied sufficiently, which can be adjusted by varying the working distance and voltage of fans, in order to maintain temperature uniform (with the fan working in certain mode). Experiments were carried out for air cooling PEMFC, with the fan system working under the mode of “blowing”, to find the optimal distance. The temperature on the export side of cathode was measured to reflect the heat dissipation by Fluke Ti25 infrared thermal imager. The load box works under constant voltage mode and automatically records output current of stack, to evaluate the output performance. Moreover, an empirical formula is fitted according to the average temperature under different conditions, with working voltage and working distance as independent variables, and average temperature as the dependent variable. The results show that the performance of the stack declines when the fan is at a distance beyond or below the optimal value. At this optimal distance, the distribution of surface temperature is more uniform, the uniformity of unit cell voltage is better, and the required working voltage of fan system is less. This work provides a guideline and serves as a reference to improve the performance of air-cooling PEMFC by increasing the stability and efficiency of the system.

In order to improve the CO₂ sorption performance of sodium-based sorbent, a series of sodium-based sorbents with amino modification were prepared by sol-gel method and the corresponding CO₂ sorption capacity were investigated in this paper. Tetraethylorthosilicate (TEOS) was chosen as the carrier precursor by comparing the amine loss rate and CO₂ sorption capacity of pure -NH₂ sorbents,and Na₂CO₃ was as the active ingredient. 3-aminopropyltrimethoxysilane (APS), 3-aminopropyltriethoxysilane (APTES), diethylenetriamine (DETA) and triethylenetetramine (TETA) were used, respectively as the amino precursor for synthesizing the composite sorbents and then drying them with conventional technique. Results showed that the sorbent modified with TETA had the highest CO₂ sorption capacity and the best pore structure, while that modified with APTES had the lowest amine loss but poor structure.

Anaerobic/anoxic/oxic (AAO)-biological aerated filter (BAF) is a two-sludge system with different SRT, which can remove nitrogen and phosphorus simultaneously in the low C/N condition. The startup of a pilot-scaled AAO-BAF system with capacity of 40—100 m³·d^-1 used for treating real domestic sewage was studied in this experiment. The AAO and BAF run independently in order to cultivate and acclimate the phosphorus accumulating organisms (PAOs) and nitrifying bacterial biofilms, respectively. When the TP concentration of AAO effluent and concentration of BAF effluent were found keeping stable, the two parts were combined. With this operation strategy, the effluent concentration of COD,, TN, TP, NTU and SS was lower than 50 mg·L^-1, 5 mg·L^-1, 15 mg·L^-1, 0.5 mg·L^-1, 5 NTU and 10 mg·L^-1 in the 58th day, respectively, indicating the successful setup of the pilot-scaled process. Comparing with the lab-scale study, the separate running had more advantage in cultivating PAOs. The formation of natural biofilm in BAF was more convenient than the method of inoculated sludge, but needed longer time. According to the analysis of microbial community diversity, the abundance of nitrobacteria was less than 3% in the AAO system, however, it was higher than 12% on the biofilm in BAF. This experiment can provide a reference for practical engineering application of the process.

Two parallel biological aerated filters (BAF), named as BAF1 and BAF2 (feeding with FeSO₄·7H₂O), were used to treat petrochemical secondary effluent. The performance of the reactors, especially the phosphorus removal ability, was investigated. In addition, the biomass and the biofilm activity were also studied. The results showed that the phosphorus removal could be enhanced obviously with the suitable dosage of FeSO₄·7H₂O (3—15 mg·L^-1). The phosphorus removal rate increased with the increase dosage of FeSO₄·7H₂O. However, the increasing trend became slowly when the dosage of FeSO₄·7H₂O was over 9 mg·L^-1. The TP removal rate was over 57.0% in BAF2 when the dosage of FeSO₄·7H₂O was 9 mg·L^-1, while it was only 7.1% in BAF1. The dosage of FeSO₄·7H₂O had no adverse effect on COD removal and the average COD removal rate in BAF2 was 5.4%,which was higher than that in BAF1. In addition, organic pollutants with high molecular weight were removed more obviously in BAF2 than that in BAF1. The dosage of FeSO₄·7H₂O had slightly effect on removal when the dosage was lower than 15 mg·L^-1. However, it decreased when the dosage was 15 mg·L^-1 due to the decrease of biofilm activity. There was almost no difference in TN removal in the two BAFs. The dosage of FeSO₄·7H₂O can decrease the amount of biofilm, but the biofilm reduction was not obvious when the dosage was lower than 12 mg·L^-1. The activity of the biofilm increased when the FeSO₄·7H₂O dosage was between 3 to 9 mg·L^-1, weakening the effect of the slightly biomass reduction, and therefore the performance of BAF2 was not affected.

The performance of Si-FeOOH, as a type of Fenton-like heterogeneous catalyst made by alkaline precipitation methods, was evaluated with degrading tetracycline hydrochloride (TH) in wastewater and reaction condition including catalyst loading, pH and hydrogen peroxide dosage examined. The results show that the degradation rate of tetracycline hydrochloride can reach up to 90% and the reaction rate 0.0504 min^-1 at catalyst loading 3.0 g·L^-1, H₂O₂ dosage 9.9 mmol·L^-1, pH 3 and temperature (25±1)℃. A comparison with FeOOH catalyst indicates that Fenton-like Si-FeOOH is better than FeOOH. Various contaminants and probe compounds (n-butanol, benzoquinone) were used to identify the active species involved in the catalytic system. The results revealed that the hydroxyl radicals (·OH) and superoxide radical (HO₂·) may be responsible for the degradation of tetracycline hydrochloride (TH). The possible catalytic oxidation mechanism was also discussed. The use of Si-FeOOH /H₂O₂ system may be a feasible approach for the elimination of widely existing pollutants.

Based on the effects of crosslinking agent on the rheological properties of polylactic acid (PLA), the cellular structure of crosslinked PLA foams was investigated via batch foaming. The results showed that when adding the crosslinking agent to the PLA, its loss tangent and complex viscosity in low frequency region and its melt strength and extensional viscosity increased. In the initial cell growth stage, the cell wall was stretched, which dramatically increased the high complex viscosity of the crosslinked PLA slowed down the cell growth rate. In the later cell growth stage, the melt strength and extensional viscosity and so increased the strength of the cell wall. Then, cell coalescence was abviously reduced and the cellular structure of the crosslinked PLA foam samples was more regular and uniform. The amount of gas loss decreased because of the high melt strength of the crosslinked PLA, which resulted in an increased expansion ratio of the PLA foam samples. The PLA foam had a maximum volume expansion ratio of 41 when adding 0.4 phr crosslinking agent.

Based on the study on preparation of sulfonate WPU emulsion adhesive of solid content at about 50% by the acetone method carboxylate-modified composite WPU emulsion adhesives was prepared. The impact of the modification on the properties of sulfonate WPU adhesive were also investigated. The results showed that when DMPA content was 1.6% (mass), A95 content was 1.8% (mass), n(PBA2000)/n(PBA3000) was 4/6 and n(HDI)/n(IPDI) was 4/6, the emulsion obtained a excellent mechanical and adhesive performance. Infrared spectroscopy showed that the composite WPU was prepared successfully. DSC analysis indicated that the melting temperature of composite WPU was about 48.03℃, while that of the sulfonate WPU was about 44.52℃. The composite WPU peak area were higher with better crystalline performance. TEM analysis revealed that both WPU emulsion particles were spherical and uniformly dispersed. Particle size distribution analysis showed that the particle size distribution of composite WPU emulsion was wider than that of the sulfonate WPU emulsion. GPC analysis displayed that the molecular weight of two types of WPU were similar, and thus the influence of modification on the molecular weight was small. TGA analysis found that the thermal decomposition reached the end at 550℃ with slight better heat resistance of sulfonate WPU. The integrated performance analysis showed that the two adhesives had better heat resistance, mechanical properties and adhesion performance, indicating that the performance of composite WPU emulsion adhesive was improved obviously, while its performance was also improved greatly as compared to the carboxylic/sulfonate WPU synthesised by the traditional method.

Tensile properties of conventional injection molding (IM) PC (polycarbonate) and injection-compression molding (ICM) parts in room and low temperature were compared. The effect of five process parameters (melt and mold temperature, compression distance, delay time and compression force) on residual stress and tensile properties of ICM parts under low temperature was investigated systematically. The results showed that higher tensile yield stress and Modulus were found for ICM parts compared with IM part. Tensile properties of ICM or IM parts were improved under low temperature. Secondary transition were discovered around -40℃ for PC. As the most influenced morphology, the residual stress of ICM parts has the opposite variation as the function of process parameters. Higher melt and molding temperature, bigger compression distance, shorter delay time and smaller compression force can be helpful to give lower residual stress value, and thus to improve the tensile properties.

The microcrystalline cellulose-g-poly[2-(diethylamino)ethyl methacrylate] (MCC-g-PDEAEMA) polymer brushes were synthesized under control by atom transfer radical polymerization (ATRP) in the ionic liquid 1-allyl-3-methylimidazolium chloride ([AMIM]Cl). Ethyl alcohol was used as the cosolvent to form a homogeneous system and solve the problem that the functional monomer N,N-diethylamino-2-ethyl methacrylate (DEAEMA) hardly dissolved in [AMIM]Cl. The synthetic mechanism of heterogeneous system and homogeneous system in [AMIM]Cl was analyzed. The experiments showed that the byproduct PDEAEMA in the homogeneous system was reduced and the grafting efficiency of the polymer brushes was improved. Meanwhile, the molecular weight distribution was narrow and ATRP was easily controlled. Optimum reaction conditions in the homogeneous system were attained at CuBr/PMDETA/DEAEMA/ethyl alcohol molar ratio of 1:15:150:300. The grafting efficiency could reach to 78.1%. MCC-g-PDEAEMA was characterized through FTIR spectroscopy, ¹H NMR spectroscopy and GPC. The results proved that the PDEAEMA side chains were covalently bonded to the MCC backbone and the molecular weight distribution of the polymer brushes were even.

Preparation of aerogels via ambient pressure drying has well been acknowledged as an extremely important way to the development and application of high performance silica aerogels. Low density (<100 kg·m^-3) and hydrophobic silica aerogels were successfully prepared via sol-gel process and ambient pressure drying by using tetraethyl ortho silicate as silica precursor. Various silica alcogels with different compression modulus were prepared by varying preparing parameters. Effects of preparing parameters on the compression modulus of silica alcogels and the density of as-prepared silica aerogels were studied. The preparing method of low density and hydrophobic aerogels by controlling the compression modulus of alcogels was accordingly explored. The results indicated that the low-density and hydrophobic silica aerogel (<100 kg·m^-3) could be prepared by controlling the compression modulus of the Alcogels within the range of 0.25~2.5 kPa. This finding provided valuable guidance for the preparation and control of low-density and hydrophobic silica aerogels via low-cost ambient pressure drying.

Blends of 3,3'-phenylmethanebis(3,4-dihydro-2H-1,3-benzoxazine)(BZ) and 4,4'-bismaleimi-dodiphenyl methane (BMI) were prepared via solvent method. The curing behaviors of the BZ/BMI blends were studied by differential scanning calorimetry (DSC), FTIR, and gelation time test. The thermal properties and mechanical properties of the BZ/BMI cured blends were studied by dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA) and electromechanical universal testing machine. The results showed that the addition reaction between phenolic hydroxyl group and the double bond occurred except for the homopolymerizations of BZ and BMI. The curing temperature and the gelation time of the blends were lowered. The cured BZ/BMI blends exhibited excellent thermal properties. When BMI content was 80%, the cured BZ/BMI blends exhibited higher glass transition temperatures (T_g) than BZ and BMI homopolymers, which reached up to 289℃. The 5% and 10% weight loss temperatures (T_d5 and T_d10) reached up to 387℃ and 422℃, respectively. Meanwhile, when BMI content was 60%, shear strength of the cured BZ/BMI blends achieved to 12.44 MPa. Furthermore, glass cloth (GF) reinforced laminates based on the cured BZ/BMI blends were prepared, and their mechanical properties and morphologies were investigated. The results showed that the enhanced mechanical properties were mainly due to the strong interfacial adhesions between GF and matrices, which was confirmed by SEM observations. When BMI content was 40%, their tensile strength, flexural strength and impact strength reached up to 394 MPa, 490 MPa and 160 kJ·m^-2, respectively.