Based on the existing research basis, the mechanism of heavy metal removal involved in the special configuration and power generation conditions of microbial fuel cell (MFC) was analyzed. The effects of device configuration, cathode type, heavy metal concentration, external resistance, pH, electron acceptor type and other factors on MFC production performance and heavy metal removal efficiency were reviewed. From the aspects of bioelectrochemistry, microbial influence, and electron acceptor competition mechanism, the effects of single factors on heavy metal removal rate and reduction products were elucidated. It is proposed that the research on MFC removal of heavy metal wastewater in the future needs to be based on the actual wastewater and construct a pilot plant to provide data support for practical applications. Further, determine the primary and secondary status and direction of each influencing factor, and adjust the influencing factors according to the existing theoretical basis to obtain a faster removal rate and an ideal reduction product. At the same time, the electrode materials suitable for heavy metal separation are screened and the physical and chemical methods for product recovery can be investigated in order to realize the real recovery of heavy metals.

In the research of lithium-ion battery electrode materials, first-principles calculation can theoretically help explain the experimental results and provide a theoretical basis for the synthesis and performance improvement of materials. At present, the application of first-principles calculation in lithium-ion battery materials mainly concentrated in the positive electrode material, for example, LiFePO₄ and layered oxide LiMO₂ (M=Ni, Co, Mn, Al, etc.), for popular ternary materials, especially there was few research on the interface structure change of modified front-rear. The application of density functional theory in the electrode material operating voltage, electron conductivity, ion diffusivity, structural stability, lithium storage capacity and thermodynamic performance prediction were reviewed. The development of more concentrated research directions was elaborated and summarized, and it provided a reference for further study of LiNi _x Co _y Mn_{1- x - y} O₂ composites using the first principles.

Mitochondria play a key role in energy metabolism process of cells. A variety of bio-active species in mitochondria, are of great importance in various physiological and pathological processes. The recent advance in organic one and two-photon mitochondria-targeted fluorescent probes for bio-active ions is reviewed. The design mechanism, recognition mechanism, characteristics and biological applications of the fluorescent probes are emphasized in detail, as well as the developing trends of these probes are prospected.

The calculation model of the saturated vapor pressure and liquid density of R32 refrigerant in the saturation line (?130—78°C, 0.00013—5.76 MPa) is proposed. Based on this, the calculation model of latent heat of evaporation is derived. The state equation for P-v-T relationship in saturated line and superheated zone was established. Based on above model, the calculation models of enthalpy, entropy and specific heat capacity in saturated line and superheated region are obtained. The average relative errors of correlation models are less than 0.16% and maximum relative errors don t exceed 3.7% compared with data from REFPROP 9.0. The deviation of state equation is less than 8.7% compared with published equation and data. The average errors of enthalpy, entropy and specific heat capacity models derived from state equation and thermodynamic relation are less than 5.2%, and maximum relative errors of all calculation models are less than 9.1%.

According to the binary molten salt system phase diagrams, the phase diagram of LiNO₃-NaNO₃-KNO₃ ternary molten salt system was calculated with the CIS model, it turned out that, the lowest eutectic melting point was 117.7℃ and the corresponding composition was x(LiNO₃) = 0.375，x(NaNO₃) = 0.075 and x(KNO₃) = 0.550. The eutectic mixture was prepared based on the predicted eutectic composition, and a experiment test was carried out by the thermal gravimetric analysis (TG) and differential scanning calorimeter (DSC). The DSC test showed that the experimental melting point was 117.7℃, which was in good agreement with the result of this calculation. The TG test results show that the ternary molten salt system is stable when the temperature is below 587.2°C, and its working temperature range is 118.3—587.2°C. The system is quite suitable as a material for high-temperature heat transfer and heat storage in solar thermal power generation.

The insulation, stirring and pressure control system of Ellis equilibrium still with double circulator for the vapor and liquid phases was improved, and a set of phase equilibrium experimental device with visual window was established. The vapor-liquid equilibrium data of terpene+(+)-3-decene system at 313.15, 373.15 and 433.15 K were determined. The thermodynamic consistency test was performed on the experimental data by area method and Van Ness test. All data were consistent with Gibbs-Duhenm. Furthermore, the VLE data were correlated by the nonrandom two-liquid (NRTL), Wilson and universal quasichemical (UNIQUAC) activity coefficient models in Aspen plus. The objective function was optimized by the maximum likelihood method and the corresponding binary interaction parameters were returned. The results show that the maximum average relative deviation between calculated values and experimental data of the vapor phase molar composition and equilibrium pressure was 0.0128 and 0.0009, the maximum root mean square deviations are 0.0003 and 0.0012 kPa, and the absolute average deviations of relative volatility are 0.09%, 0.03% and 0.04%, respectively.

An experimental study on phase equilibria of the system Na⁺// \mathrm{S} {\mathrm{O}}_4^{2-} , \mathrm{C} {\mathrm{O}}_3^{2-} , \mathrm{N} {\mathrm{O}}_3^{-} -H₂O at 313.15K was done by the method of isothermal solution saturation. The solubility and physical properties (ρ, η, n _D) of the equilibrium quaternary system were measured, and the corresponding phase diagram, water diagram and physical property (ρ, η, n _D) diagram were obtained based on the data measured. The results show that: the phase diagram of Na⁺// \mathrm{S} {\mathrm{O}}_4^{2-} ， \mathrm{C} {\mathrm{O}}_3^{2-} ， \mathrm{N} {\mathrm{O}}_3^{-} -H₂O at 313.15 K consists of two invariant points, six univariant curves, and five crystallization regions which are NaNO₃，Na₂SO₄，Na₂CO₃·H₂O, Bur(Na₂CO₃·2Na₂SO₄),and Da(NaNO₃·Na₂SO₄·H₂O), respectively. The Bur crystallization field occupies the largest part, which indicates it is easier to crystallize in the mixing solution. All the physical properties (ρ, η, n _D) change regularly with J(Na₂SO₄) composition. Bur(Na₂CO₃·2Na₂SO₄), Da(NaNO₃·Na₂SO₄·H₂O) and crystalline hydrate (Na₂CO₃·H₂O) are proven to co-exist in the quaternary system, whereas no solid solution is found in the temperature range investigated, which means the reciprocal quaternary system is a complex eutectic type. The data and conclusions obtained from the experiment are of great significance for the development of crystallization salt separation process of high salt wastewater produced by coal chemical process and the realization of comprehensive utilization of resources.

Acetonitrile is easy to form an azeotropic mixture with water and it is impossible to separate them through ordinary distillation technology. In this work, ionic liquids (ILs) are employed as entrainer to separate acetonitrile and water. The isobaric vapor liquid equilibria (VLE) of acetonitrile + water + 1-ethyl-3-methylimidazolium diethylphosphate ([EMIM][DEP]), acetonitrile + water + {1-ethyl-3-methylimidazolium acetate ([EMIM][OAC]) + [EMIM][DEP]} are determined at atmospheric pressure (101.3 kPa) in a glass equilibrium still with a vapor cycle, indicating that the selected ILs can well improve the separation of acetonitrile and water mixture, and further eliminate its azeotropy. The VLE data of ternary and quaternary mixtures containing ILs are well correlated with NRTL model, and the binary interaction parameters of acetonitrile-[EMIM][DEP], water-[EMIM][DEP] and [EMIM][OAC]-[EMIM][DEP] are obtained. The experimental VLE was predicted using COSMO-SAC and the results were satisfactory. The interactions among different molecules are analyzed through quantum calculations showing that the interactions between water and ILs are stronger than ones between water and acetonitrile so that the used ILs here can improve the separation of acetonitrile and water.

The Eulerian-Lagrangian method is employed to describe the gas-liquid flow and the heat and mass transfer process in a full-scale wet flue gas desulfurization(WFGD) tower, which is in operation at a 330 MW coal-fired power unit. Instantaneous chemical reactions involving 13 dissolved species in aqueous phase are assumed to be at equilibrium obeying mass balance for the specific chemical compositions and electro neutrality. The gas-liquid flow model is coupled with mass transfer and chemical reactions procedures through user defined functions (UDFs). The gas-liquid hydrodynamics, droplets evaporation and SO₂ chemical absorption is predicted in the spray scrubber. Radial distribution characteristics of SO₂ concentration and pH of the droplets are obtained and the effect of gas-liquid flow behavior on chemical absorption process is analyzed. The results show that the local liquid-gas ratio distribution is one of the key factors affecting the radial distribution of SO₂. Furthermore, the absorption performance of the desulfurization tower can be improved by controlling the two-phase flow pattern in the area around the wall and that beneath the main pipe. The drop rates of pH increase with the raise of SO₂ concentration in flue gas or the decrease of droplet diameter. Besides, the higher concentration of SO₂ in gas phase or the smaller characteristic size of droplet can accelerate the process that the concentration of each chemical component reaches a stable state.

A lab-scale multifunctional microwave freeze-dryer was designed and assembled to explore the microwave freeze-drying process of initially unsaturated frozen material with preformed pores. Initially saturated and unsaturated frozen samples were prepared by using“soft ice”freezing technique using vitamin C as the solute. The results showed that the saturated sample by soft ice freezing can effectively avoid structural collapse during freeze-drying, and the initially unsaturated frozen material can significantly enhance the freeze-drying process. Under 35℃ of the ambient radiation temperature and 20 Pa of the drying chamber pressure, the initially unsaturated sample saved 30.4% of drying time compared with the saturated one. SEM images of dried products revealed that the initial unsaturated material had a loose solid substrate and a spherical pore structure, which is favorable to the migration of sublimated/desorbed vapor. Appropriate increasing the radiation temperature was conducive to reducing the drying time and changing the chamber pressure had insignificant effect on freeze-drying. With a wave-absorbing material―silicon carbide (SiC) as the supporting pad of sample, microwave heating can further enhance the freeze-drying process. Under the same operating conditions, the drying time for microwave freeze-drying (5 W input) of the unsaturated sample can be 28.1% shorter than that for conventional freeze-drying (0 W input), and 50.0% shorter than that for conventional freeze-drying of the saturated sample. SiC assisted microwave freeze-drying of the initially unsaturated frozen material is a feasible way to achieve the simultaneous enhancement of heat and mass transfer in freeze-drying.

Based on the pseudo-fluid characteristics of PM2.5 in aerosol, the pseudo mass transfer mechanism of PM2.5 in gas-liquid heat and mass transfer boundary layer was analyzed, considering the convective mass transfer of PM2.5 caused by thermophoresis, diffusiophoresis and the gas movement, a pseudo mass transfer model of PM2.5 in gas-liquid cross flow array based on thermophoresis and diffusiophoresis is established, and the accuracy of the model is verified through experiments. The influencing of thermophoresis caused by gas-liquid temperature difference, diffusiophoresis caused by gas-liquid humidity difference and particle size on the pseudo mass transfer coefficient of PM2.5 was investigated under fixed convection conditions. The experimental data statistics are consistent with the model expression trend. Under the initial temperature difference of 40℃ and initial humidity of 0.118 kg/kg, the predicted value of the PM2.5 pseudo-mass transfer coefficient model of the exhaust gas cross-flow array is 3.33×10^-3 m/s, experimental value 3.75×10^-3 m/s.

Compared with conventional fluids such as water and ethylene glycol, the excellent heat transfer effect of nanofluids has made it one of the hotspots of research in the past decade. In this paper, the heat conduction enhancement mechanism of nanofluids is simulated by a reverse non equilibrium molecular dynamics method. The heat flux density and thermal conductivity of nanofluids change with the addition of Cu nanoparticles in Ar, and the volume fraction of nanoparticles changes the energy transfer process in nanofluids to a certain extent. Furthermore, the microscopic mechanism of the enhancement of thermal conductivity of nanofluids is analyzed. It was found that the addition of nanoparticles made the microstructure of nanofluids similar to that of crystals. Under the condition of smaller particle size, the effect of temperature gradient on the fluid is obvious.

Spray drying for powder production has a wide range of applications. On-aim control of surface morphology of spray dried particles is critical for achieving improved powder quality. This work aims at a molecular scale coarse-grained model that can characterize evaporation induced self-assembly of solute during the drying process. Thus, surface morphology evolution under different drying conditions can be predicted. The lattice Monte Carlo model developed in this work can take care of spherical shaped solute molecules and comprehensive interactions between species in the system. The analysis method is capable of quantifying solvent residue and solute distribution as well as its assembly structure. The simulations carried out in 2D show that different assembly structures can be formed under investigated conditions. The decrease of solvent chemical potential energy leads to the decreased solvent residual ratio. With the increase of initial solute concentration, the final assembly pattern changes from disk-shape to net-shape. Furthermore, assembly patterns can be tailored through manipulating interactions between species in the system.

A mathematical model is established to investigate the gravity-driven draining process of a vertical thin liquid film containing insoluble surfactants, where the top of film is assumed to fix to a vertical plate and the bottom of film is connected with a surfactant solution pool. Lubrication theory is used to derive a coupled equation set for describing the evolution of the film thickness, surfactant concentration and surface velocity. The equation set is solved numerically by the FreeFem program based on finite element method. The characteristics of film evolution are examined and the effect of characteristic parameters on the process of film evolution is analyzed. Simulated results indicate that the Marangoni effect is a crucial factor affecting the film drainage process, the strong Marangoni effect, Ma, leads to the bodiness of the film thickness. Besides, for large values of Ma, both the film thickness and solute distribution tend to be more uniform. The effect of surface viscosity on the drainage of surfactant film cannot be neglected, the reduction of interfacial viscosity S results in the faster drainage process and the more rapidly decrease of film thickness. However, it has no effect on the uniformity of film thickness.

Ammonia gas temperature programmed desorption (NH₃-TPD), UV-visible spectroscopy and small fixed-bed reactor were used to study the surface acidity of nano-H-ZSM-5 zeolite modified by alkali metal sodium ion and transition metal zinc ion. The results showed that alkali metal ion Na⁺ modification can effectively eliminate the strong acid sites and reduce the acid amount of the zeolite, which consequently optimized the products distribution of aromatization process by suppressing the production of low-value by-products like methane, ethane or propane. The optimum Zn loading for aromatics production was 3% (mass), while further increasing Zn loadings resulted in high yield of dry gas. The suitable reaction temperature for C₅－C₈ alkanes aromatization was 530℃.

The tubular ceramic outer membrane with average pore diameters of 5, 20 and 50 nm was made into a membrane condenser, and a membrane condensation pilot test device with a membrane area of 0.3 m² was set up to carry out the recovery of water and waste heat resource from flue gas using ceramic membrane condensers. The recovery performance of two-stage membrane condensers with different installation types was investigated. The effects of relative humidity of inlet gas, inlet gas temperature, inlet gas velocity and average pore size of membranes on mass and heat transfer performances were systematically studied. The results showed that the higher flux and recovery ratio can be achieved when the gas and water flowed within the membrane condenser in a tandem way. The water flux increased with the increasing of relative humidity, temperature and velocity of the inlet gas. The water recovery ratio can be enhanced by increasing relative humidity, temperature of the inlet gas and decreasing gas velocity. In addition, a three-stage condenser installed with 50 nm pore-sized ceramic membranes displayed a better water and heat recovery performances. The average pore size of ceramic membranes had remarkable impact on the mass transfer process rather than the heat transfer process. In this work, the highest water flux and recovery ratio of three-stage membrane condensers were 38.5 kg·m^–2·h^–1 and 50.6%, respectively. Compared with conventional heat exchangers, ceramic membrane condensers can recover water and heat simultaneously, during which the overall heat transfer coefficient could reach as high as 415 W·m^–2·℃^–1. The ceramic membrane condensers can not only effectively relieve the visible pollution known as “smoke plume”, but also have great potential applications in the resources recycling and environmental protection.

The dust exhaust port at the bottom end of the cyclone separator adopts an ash or ashless bucket structure according to the requirements of the gas-solid separation process. The existence of the hopper has an important influence on the flow field inside the cyclone separator, and then the separating performance. But the research of this aspect is few. Therefore, the tangential velocity of gas flow field in the cyclone separator with and without hopper was measured by using hot wire anemometry (HWA). The results show that the swirling flow in the cyclone is highly instability, and the real tangential velocity fluctuates with low frequency and high amplitude. Further, the existence of hopper leads to strong instability of swirling flow field near the dust outlet, which is characterized by intense fluctuation of real tangential velocity. Fast Fourier transform analysis of measured data shows that the real tangential velocity of cyclone separator with hopper has two dominant frequencies, one exists in the whole space and another one presents in the local area near the dust outlet. However there is only one dominant frequency in the whole space of the cyclone without hopper. The dominant frequency of the whole space is caused by the swing of the swirling flow center around the geometric center, while the local dominant frequency is caused by the backflow from the hopper. So, the swing of the swirling flow from the hopper is superimposed on the swing of the swirling flow in the separation space, which forms two dominant frequencies near the dust outlet region.

High temperature gas-cooled reactor pebble-bed module demonstration power plant (HTR-PM) is designed to operate over wide conditions to cope with the ever changing power demand. Model-based operation optimization is challenged by the inability to obtain models that are well-suited for significant loads changes. To deal with plant-model mismatch, an adaptive MA (modifier adaptation) algorithm is proposed for significant load changes in HTR-PM. This algorithm corrects the optimization model by process feedback information, which promotes the consistency between the optimization model and the plant optimization problem, and thus drives model-based operation optimization to converge to the true optimum. Within the framework of trust region, the adaptive MAs algorithm adaptively updates the model and determines the application range of the optimization model based on model evaluation, so as to confine the optimization model to an appropriate operating region. Moreover, the trust region framework reduces the sensitivity of algorithm performance to algorithm parameters. The proposed algorithm is applied to significant load changes in HTR-PM where both reactors undergo load changes synchronously, and the results show the efficiency of this method.

It is of great value to improve the enzymatic properties including selectivity by chemical modification at the same time. Four kinds of ionic liquids, prepared from N-acetyl-proline as chiral source, were used to modify porcine pancreatic lipase (PPL). Modification degree was determined by 2,4,6-trinitrobenzene sulfonic acid (TNBS) method, and enzyme activity was determined by the hydrolysis of 4-nitrophenyl palmitate (pNPP). As expected, the catalytic properties of PPL were changed obviously after modification. The thermal stability, organic solvent tolerance, adaptability to temperature and pH changes, even enantio selectivity of all the modified enzymes was improved simultaneously. Research results also showed that the composition and configuration of ionic liquids (Ils)had an important influence on the enzymatic properties of modified enzymes. The PPL modified by [BMIM] [N-AC-L-pro] showed obvious better catalytic performance than that modified by [BMIM] [N-AC-D-pro], while the catalytic properties of PPL modified by [N-AC-L-pro] [Cl] and [N-AC-D-pro] [Cl] only showed slight difference. PPL modified by [N-AC-L-pro] [Cl] showed the highest activity, increasing by 2.5 folds as much as the original enzyme. Overall, PPL modified by [BMIM] [N-AC-L-pro] demonstrated the best enzymatic performance: the hydrolysis activity was increased by 1.0 time, the optimum temperature was raised to 55℃, the thermostability was improved by 2.6 times（50℃，2.5 h）, the enantio selectivity was increased by 1.5 times, the stability in the strong polar protonic solvent of methanol was enhanced by 1.3 times, and also showed better tolerance of temperature and pH. The fluorescence spectroscopy and circular dichroism spectroscopy (CD) characterizations confirmed that chiral proline ionic liquids were grafted onto the surface of PPL successfully, resulting in the conformation change of PPLs, which led to the improvements of the catalytic performance of modified PPLs. Through this study, chiral ionic liquids have proven to be a new and effective modifier for various catalytic properties of enzyme molecular modification and selectivity enhancement.

The pyrolysis coupling and grading of rice husk-loaded urea was studied by fixed bed pyrolysis reaction system. The experiment used three-stage condensation method to compare the pyrolysis temperature (400, 500, 600℃) and condensation. The mechanism of nitrogen-enriched biomass pyrolysis and fractional condensation was explored. The results showed that the Maillard reaction promoted the conversion of carbonyl compounds to nitrogenous heterocyclic compounds (NHCs) in the nitrogen-enriched pyrolysis process. The high value-added compounds were enriched by fractional condensation. Phenols with high dew points were enriched in first stage (Oil-1), while the second stage (Oil-2) enriched the low dew points NHCs. Liquid product yield, phenols content in Oil-1 and NHCs content in Oil-2 were increased with the pyrolysis temperature raised, especially the NHCs content reached highest (20%) in Oil-2 at 600℃. However, the liquid product yield and phenols content were decreased when the pyrolysis temperature was higher. As the first stage condensing temperature increased, the enrichment of phenols and NHCs were further improved, while the moisture content of Oil-1 was decreased. Particularly, when the first stage condensing temperature was 90℃, the water was almost condensed in the second stage (84%), and Oil-1 had the lowest water content [16%(mass)] and highest phenols content (43%).

By using ReaxFF software, the process of forming the initial soot particles in the catalytic slurry at 600－2500 K was studied based on ReaxFF and the model compound of decalin, naphthalene, 2-methylindole and 1-ethylindole as catalytic oil slurry. The effect of water molecules on the formation of NSPs at 2500 K has been investigated. The study shows that the formation of the NSPs at 600 K is mainly due to the physical aggregation. At the temperature range of 1100－1700 K, model compound molecules are in a dynamic process of gathering and separating, and cannot transform from monomers to soot particles. At the temperature above 2100 K, the formation of NSPs is mainly due to the chemical nucleation. The carbon-hydrogen bonds of the model compound are broken firstly, then the carbon-carbon bonds are broken into a large number of short carbon chains, and the short carbon chains are bonded and cyclized to form the initial soot particles. At 2500 K, water molecules inhibit the chemical nucleation process of the model compound molecules, and the inhibition effect to the formation of the NSPs is enhanced with the increase of the hydrogen-to-carbon ratio. Water molecules produce hydrogen radicals and hydroxyl radicals, which directly lead to the formation of a large number of short carbon chains due to the cleavage of side-chains and carbon-carbon bonds. These carbon chains continue to be consumed by hydrogen radicals and hydroxyl radicals to form carbon monoxide, carbon dioxide, hydrogen, methane, etc. The water molecules can promote the formation of short carbon and inhibit the transition of short carbon chains toward the formation of NSPs.

A chemical chain methane dry reforming combined hydrogen production process was proposed. The process consists of a reduction reactor, a dry reforming reactor, a steam reactor and an air reactor to obtain a synthesis gas having a variable H₂/CO ratio while achieving hydrogen production. In this study, thermodynamic validation was carried out at 900℃ and 1.01×10⁵ Pa, and experiments were performed to verify the feasibility of the process in a fluidized-bed reactor using Fe₂O₃/Al₂O₃ oxygen carrier. It was found that a high conversion of CO₂ and CH₄ to syngas can be achieved on the reduced iron oxygen carrier. When the reduction extent of the oxygen carrier was 33%, the CH₄ conversion and CO yield over 98% and 94%, respectively. During the dry reforming stage, the ratio of CH₄/CO₂ was variable. Partial oxidation of excess CH₄ by active lattice oxygen increased H₂/CO molar ratio of syngas and reduced the carbon deposition. Carbon deposition formed since the active lattice oxygen has been depleted, which would react with steam in the next steam oxidizer and causing the hydrogen purity reduced.

With the development of natural gas wells, the wellhead pressure is gradually reduced, and the pressurized gathering and gathering of low-pressure wellheads has become a research hotspot. At present, the common natural gas injection technology has a poor adaptability to gas well pressure and flow due to its fixed structural size, which makes its operating efficiency generally low. Based on this, the cone core adjustable ejector device was designed and processed, and its performance under variable working conditions was studied experimentally. The results show that with the inward movement of the adjustable cone, the flow rate of the high pressure port is reduced, and a wide range of flow adjustment of about 70% can be achieved; Moreover, the flow rate of the low-pressure port is almost unchanged during the adjustment process, so that the ejector rate of the device is improved, and the cone-core adjustable ejector technology has strong resistance to flow fluctuation. With the deepening of adjustable cone, the optimal expansion ratio of the device increases. Thus, the adaptability of the device to the condition of large expansion ratio is improved. At the same compression ratio, the efficiency of the device's ejection increases with the depth of the adjustable cone, but it reduces the range of compression ratios that the device effectively emits.

Aiming at the performance description of using adsorbent to control the behavior of K-containing gas in flue gas during biomass combustion, the performance and influencing factors of kaolin and coal fly ash trapping KOH (K₂CO₃), KCl and K₂SO₄ were investigated by one-dimensional plug flow reactor model. After comparing the model calculations with the experimental measurements in the literature to verify the rationality of the model and to determine the kinetic parameters, the differences in the performance of kaolin and coal fly ash adsorbing various K-containing gases were compared. The results showed that employing the global kinetic model and a single set of kinetic parameters was capable of predicting the amount of K captured by kaolin and coal fly ash under a wide range of reaction conditions and the kinetic parameters determined were reasonable. Within the given ranges of K concentration and flue gas temperature, the patterns of K capture by kaolin and coal fly ash were similar, both increasing with the increase of flue gas temperature and K concentration, but the effect of K concentration on kaolin adsorption was more obvious. The capabilities of K adsorption by both kaolin and coal fly ash were: KOH > KCl > K₂SO₄, but the adsorption capability of kaolin was much stronger than coal fly ash.

The flue gas emitted by coal-fired power plants contains a large amount of water vapor, and the calcium chloride solution circulating dehumidification technology has a good dehumidification potential. To study the regeneration performance of the CaCl₂ solution after dehumidification, the droplet flashing process was numerically simulated by using Matlab software, and a test bench on regeneration of CaCl₂ solution by spray flash evaporation was set up. The effects of flash pressure, initial solution temperature, concentration, and solution flow rate on the regeneration of CaCl₂ solution were investigated. The results showed the accuracy of the mathematical model. The difference between vapor pressure on the solution surface and the regeneration pressure and the superheat of the solution are the key factors affecting the regeneration efficiency. The concentration of Cl^- in the condensed water after flashing is less than 0.2 mg/L. CaCl₂ solution with a concentration of 35%, a regeneration temperature of 60℃, a regeneration pressure of 10 kPa, and a flow rate of 0.2 m³/h will has a rate of more than 5 kg/h water recovery quality.

The present work proposes a novel system which integrates high-sulfur petroleum coke chemical looping gasification (CLG) and sulfur recovery. Depending on the gas-solid reaction, CLG process has the ability to control the reaction pattern to obtain the mole ratio of H₂S and SO₂ as 2 in the syngas. The chemical chain gasification is combined with the catalytic conversion unit in the Claus process, and the high sulfur petroleum coke chemistry is proposed. Focusing on the core part of the system, CLG section, the simulation using the Aspen Plus was performed. The thermal input was designed as 10 MW_th with high-sulfur petroleum coke as fuel. Iron ore and steam were used as oxygen carrier and gasification agent respectively. Effects of O/C, gasification temperature on the thermal balance during CLG process, syngas yield, effective gas content and sulfur conversion were investigated. Results indicated that increasing O/C leads to a decrease in the production yield of syngas, but the system gradually shifts from the endothermic to exothermic. When O/C is between 0.8669 and 0.9535, the system can maintain the heat balance without extra energy. Further, the increase of temperature is beneficial to syngas production. The CO concentration increases with increasing temperature and reaches 2.15 m³/kg at a gasification temperature of 975℃. A high ratio of O/C and gasification temperature can enhance H₂S conversion during gasification process with a consequence of H₂S concentration decreasing and SO₂ concentration increasing. Furthermore, in the best case of the mole fraction of H₂S to SO₂ as 2, a negative correlation on the factors of O/C ratio and temperature was found. The cold gas efficiency is 64.09% at the conditions of the O/C ratio as 0.8669 and the gasification temperature of 900℃.

Taking actual domestic wastewater (C/N = 3.5) as influent substrate and carbon fiber as biological carrier (filling rate of 35%), the simultaneous nitrification and denitrification via nitrite was achieved in a sequencing batch biofilm reactor (SBBR) using limited DO concentration and intermittent aeration respectively at normal temperature of (20±2.0)℃. The ammonia oxidizing bacteria (AOB) became the dominant species in the SBBR in 120 d. The “feast-famine” characteristics of AOB led to the rapid accumulation of nitrite under intermittent aeration conditions. Most of COD was taken up and converted to polyhydroxyalkanoate (PHA), which was used as internal carbon sources for the following denitrification process. Under the conditions of low oxygen (DO=0.5 mg/L) and intermittent aeration, the removal efficiency of \mathrm{N} {\mathrm{H}}_4^{+} -N in both reactors was more than 95%. The yield of N₂O was 4.38% and 3.65%, the SND efficiency was 77.9% and 87.1%, respectively. The effluent was mainly \mathrm{N} {\mathrm{O}}_2^{-} . Both the lower DO concentration and intermittent aeration could reduce the degradation rate of COD, provide the external carbon source needed for denitrification, and reduce the amount of N₂O emissions. The aerobic denitrification process of AOB and denitrification process of \mathrm{N} {\mathrm{O}}_x^{-} -N using internal PHA as carbon source can promote the emissions of N₂O. The anoxic/aerobic environment under intermittent aeration conditions reduced the substrate of aerobic denitrification substrate and is beneficial to the reduction of N₂O emission.

In view of the scaling of suspension carrier in CANON-MBBR (completely autotrophic nitrogen removal over nitrite-moving bed biofilm reactor), the main components and causes of scaling were verified. EDTA-2Na was used to remove scaling and preventive measures were taken. The results show that the scaling is caused by the formation of calcium carbonate and its attachment to the suspension carrier due to the high pH of the system. EDTA-2Na was selected to be the scale removal agent and the scaling phenomenon disappeared gradually with the operation of the reactor after adding 20 mg·L^-1 EDTA-2Na. The total nitrogen removal load of the reactor was restored from 0.27 kg N·(m³·d)^-1 to 0.83 kg N·(m³·d)^-1 within 80 d. The recovery rate was close to 100%. In view of the negative correlation between the reactor height and the alkalinity blowing degree of the system, in order to prevent the scaling caused by the high pH due to alkalinity blowing. The reactor height was raised and the pH of the system was reduced to normal level, the necessary conditions for scaling were eliminated, and the system load remained stable. High-throughput sequencing analysis of microorganisms in different stages of the reactor showed that scaling on suspension carriers occupies the effective specific surface area of suspension carrier. As a result, the abundance of AOB and AnAOB in CANON functional microorganisms decreased from 10%, 20% to 5% and 4% respectively. In addition, the diversity of biofilm population on the surface of suspension carriers also decreased. After scaling was eliminated, the abundance of AOB and AnAOB increased again and eventually reached 11% and 23% respectively. The diversity of community decreased slightly, and the degree of species homogenization tended to be stable.

Nitrogen-doped porous graphene/carbon composites(NPGC) were prepared by a simple and template free method.Its morphology, composition and structure were characterized by SEM, XRD, Raman and XPS. The electrocatalytic performance of NPGC on oxygen reduction reaction(ORR) was measured by a rotating disk electrode. The results showed that porous carbon generated by hydrothermal treatment of glucose was successfully compounded with graphene. After carbonization and activation at 950℃, a three-dimensional lamellar porous network structure with good permeability and structure was formed. The N content of NPGC is as high as 9.47%. NPGC showed relatively high initial potential [0.87 V(vs RHE)] and limiting current density (4.7 mA?cm^?2) for ORR in KOH solution, and the average number of ORR transferred electrons was 3.8. Compared with commercial Pt/C electrocatalyst, NPGC showed high methanol tolerance and long-term durability, and had the advantage of low preparation cost, which has broad application prospects in industry.

Diethylamine (DEA) was adopted as the low-cost template to prepare hollow fiber supported SAPO-34 molecular sieve membranes for CO₂/CH₄ separation. The membranes were synthesized by the secondary-growth method using ball-milled SAPO-34 seeds. Effects of seed particle size, contents of DEA and aluminum source in precursor and crystallization time on structure, morphology and separation performance of the membranes were investigated extensively. The SAPO-34 membranes induced with ball-milled seeds were more compact than those with original seeds. The increase in DEA content was beneficial to transform SAPO-11 crystals to cubic SAPO-34 crystals in the membrane layer. When the content of diethylamine is too high, the SAPO-34 membrane is not formed on the surface of the carrier. When the content of aluminum in the synthetic liquid is low, the crystallization of the molecular sieve membrane is not complete. When the content of the aluminum source is too high, the crystal grain size on the surface of the membrane is gradually reduced or even difficult to nucleate, and the thickness of the membrane layer is thinned, and it is difficult to form a continuous film. In that case, it was seen that the membrane surface became uncompacted and the membrane thickness decreased. The increased crystallization time led to thicker and denser zeolite membrane. When the precursor composition was 1.0Al₂O₃∶0.9P₂O₅∶0.6SiO₂∶2.0DEA∶100H₂O and the crystallization time was 36 h, the as-synthesized membrane achieved the best CO₂/CH₄ separation selectivity of 80 as well as CO₂ permeance of 1.11×10^?6 mol·m^?2·s^?1·Pa^?1.

Designing a special structure that satisfies both the high absorption in the visible light band and the high reflection in the far infrared band is an important challenge in the preparation of infrared low emission coatings. The reflectance spectra of visible and far-infrared region were measured by UV-Vis spectrometer and Fourier transform infrared spectrometer. The results show that the size of the nanoparticles and the thickness of the dielectric layer influence the reflective performance of the film. The visible absorptivity is up to 64.07%, simultaneously the reflectance in the far-infrared region is not more than 2.29%.

The functionalized ionic liquids 1-butyl-3-methylimidazoliumbis(trifluoromethanesulfonyl)imide (BMIMTFSI) was synthesized as a high-pressure lithium ion battery electrolyte additive for inhibiting the oxidation of organic solvents to enhance carbonic acid. The electrochemical behaviors of LiNi_0.5Mn_1.5O₄/Li batteries and the surface morphology of LiNi_0.5Mn_1.5O₄ electrode were studied by charge-discharge test, electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and scanning electron microscopy (SEM). The results show that when 20% (vol) BMIMTFSI is added to carbonate-based electrolyte, the highest discharge capacity of LiNi_0.5Mn_1.5O₄/Li cells is 126.81 mA·h·g^-1 at 0.2C rate, and the discharge capacity is 109.36 mA·h·g^-1 at high rate of 5C, which is 91.7% higher than that in 1.0 mol·L^-1 LiPF₆-EC/DMC electrolyte. And the discharge capacity retention rate of LiNi_0.5Mn_1.5O₄/Li cells reaches about 95% after 50 cycles at 0.2C rate, which is nearly 10% higher than that with blank electrolytes. The results of SEM showed that a uniform and compact solid electrolyte interface (SEI) film was attached to the surface of LiNi_0.5Mn_1.5O₄ electrode after adding BMIMTFSI to carbonate-based electrolyte.

Nanomaterial modified anode can significantly improve the performance of microbial fuel cell (MFC). The effects of graphene, polyaniline and graphene/polyaniline composite modified electrode on the power output of MFC is mainly explored in this paper. Graphene was electroplated on the surface of the carbon cloth by electrochemical method, and the polyaniline was further prepared by in-situ polymerization to modify the carbon cloth electrode. The modified electrodes were further loaded into a dual-chamber MFC, and the power generation performance was measured. It was observed by scanning electron microscopy that graphene and polyaniline could be modified on the carbon cloth, and polyaniline adhered to the surface of the carbon fiber or graphene thin layer to form a rod-shaped nanostructure. In terms of electricity production performance, the maximum output voltage of MFC loaded with graphene/polyaniline composite modified electrode reached (291±22) mV, which was more than 175% higher than that of the control group loaded with unmodified carbon cloth electrode. The maximum power density of the graphene/polyaniline composite modified electrode group reached (653 ± 25) mW·cm^-2, which was 10.5 times of the control group. The results show that the graphene/polyaniline composite modified electrode can effectively utilize the advantages of good conductivity of graphene and high biocompatibility of polyaniline, and significantly improve the power output of MFC.

Using cassava starch as raw material and acetic anhydride as acylating agent, acetylated starch was prepared in the slurry system, and acetylated starch granules were chemically surface-gelatinized with 4.3 mol·L^-1 CaCl₂ solution to obtain different surface gelatinization degree. The morphology and crystalline structure of the remaining granules were characterized by SEM and XRD. The content of acetyl group in the remaining granules was determined by saponification method, the distribution curve of substituent content in the radial direction of starch granules was fitted by least square method, and the factors influencing the homogeneity of acetylation and the distribution of acetyl group were investigated. The results showed that the distribution of acetyl groups in starch granule was inhomogeneous which was external high and internal low, more than 30% of the acetyl groups were distributed in the external region of the contrast radius from 0.9 to 1.0, while only 28% of the acetyl groups were distributed in the larger range from 0 to 0.7; with the increase of reaction temperature, reaction time and the amount of acylating agent, the dispersion degree of group distribution in starch granule decreased, which was favorable for more uniform of acetylation and distribution of acetyl groups. With the degree of surface gelatinization increased, the remaining particles could still maintain the morphology and “A” type crystalline structure of cassava starch, but the particle size decreased slightly, the crystallinity generally showed a downward trend while some of them had a sudden jump. The above results indicate that alternating crystalline and amorphous structures exist in the granule of cassava starch, and the proportion of crystallization and amorphous zones in various regions is different. Appropriate changes in reaction conditions can improve the inhomogeneous status of acetylation and distribution of acetylation groups in the granule of cassava starch.

The PVDF membrane was modified by graphene oxide (GO), and the compacted GO/PVDF composite membrane was prepared by immersion precipitation phase transformation. The hydrophilicity, pure water flux and surface zeta potential of the membrane were investigated. Rhodamine B and methyl orange were selected as positive and negative charge dyes to investigate the adsorption, desorption and retention properties of membranes. The results showed that the pure water flux of membrane increased from 45.10 L/(m²·h) to 58.40 L/(m²·h). When the content of GO was 0.50%(mass) (M2), the comprehensive performance of membrane was better. GO/PVDF composite membranes had a good adsorption effect on Rhodamine B. After 1.5 d, the adsorption capacity of M0—M3 were 1.02, 1.24, 1.79 and 1.49 mg/g respectively. The decolorization rate of Rhodamine B by ethanol was over 80%. The adsorption capacity of M2 was only 0.46 mg/g, and decolorization rate of methyl orange by 0.10 mol/L HCl solution was over 86%. The retention rates of two dyes remained above 57.60% and 57.20%. This study provided a scientific basis for the preparation of nano-materials modified membranes and their characteristics of organic dye removal.

For the problem of insufficient water resistance of ammonium polyphosphate (APP) and poor compatibility with polymer materials such as polypropylene(PP), APP (EM-APP) is coated with formaldehyde-melamine (melamine resin) and epoxy resin double layer. The coating effect was characterized by means of FT-IR, SEM, TGA and water solubility test. The effects of coating APP on flame retardant PP were investigated by means of horizontal vertical combustion, oxygen index instrument, cone calorimeter and thermo gravimetric-infrared combination, and the flame retardant mechanism was discussed.The results show that the coating operation not only improves the water resistance of APP effectively, but also introduces the coating layer with charring function to the surface of APP. Compared with APP, the residual carbon content of EM-APP increases by 14.2% at 800℃. When the same mass fraction of flame retardant is added to polypropylene, EM-APP has higher flame retardant efficiency, and its heat release rate, total heat release, smoke release rate and total smoke release were significantly reduced. The compatibility between APP and PP is improved by coating treatment. The coatings play a synergistic role in charring during combustion.

As(Ⅲ) adsorbent (called modified EMRs) was prepared by modifying the industrial waste electrolytic manganese residues (EMRs). The effects of NaOH dosage, ultrasonic and microwave on its surface structure and adsorption performance were investigated. The results showed that most of the Si, S and Ca were removed by ultrasonic reaction (200 W) for 2 h with solid-liquid ratio M (EMRs)∶V(NaOH, aq) = 1∶10 (C _{NaOH, aq} = 2.0 mol·L^-1). Fe, Mn and other active adsorption groups were deposited on the surface after the microwave (700 W) was reacted for 5 min. Finally, the adsorbent dried at 105℃. The SEM results show that the surface of the material has a lamellar nanostructure and good adsorption performance for arsenic. The initial As(Ⅲ) concentration of 50 mg·L^-1 wastewater effluent can be reduced to 0.042 mg·L^-1. The national surface water environmental quality standard Class I water quality requirements (GB 3838—2002), at the same time, can be continued after being regenerated by 3% NaOH solution. XPS results show that the adsorption of arsenic by modified EMRs is closely related to the increase of active species such as Fe₃O₄, FeOOH and MnO₂ on As(Ⅲ) adsorption or oxidation.

The external corrosion evaluation of the pipeline can provide a basis for the optimization of the pipeline inspection and maintenance program. Considering the complexity and uncertainty and timeliness of factors of external corrosion of buried pipelines, the grey relational analysis method was introduced to pipeline corrosion evaluation field, so as to propose a multi-level grey dynamic evaluation of external corrosion of pipelines based on cooperative game. Firstly, an evaluation index system of external corrosion of pipelines, in which the soil corrosion, external coating performance, cathodic protection system and stray current interference were included, was established. The subjective weights of the indexes obtained from expert qualitative analysis were quantified by applying improved analytic hierarchy process based on group decision-making. The objective weights of indexes were obtained by detecting real-time data information. After getting the two weights, the synthetic weight of each index was obtained by cooperative game. The dynamic multi-level grey evaluation was established which can be used to determining the risk grade of external corrosion of buried pipelines to be measured. The performance of the proposed method was tested on the practical example about corroded buried pipeline in a certain area. The effectiveness and reasonableness of the constructed model was validated.

A typical cylindrical three-dimensional underground garage is selected as the object of this research. In the condition of the natural ventilation, star-ccm+ software was used to simulate the fire scene in the garage. The negative layer, the negative six layer and the negative ten layer are selected as the fire points respectively. It calculated out that, the deeper the fire source, the higher the center temperature of the roof. The temperature values are respectively 860, 927 and 942℃. The center temperature of parking spaces on the same floor as the fire are all higher than 200℃. When a car get fired, its adjacent vehicles, upper vehicles and relative vehicles will be ignited at about 240, 312 and 322 s. The deeper the fire source, the shorter the time it takes to ignite its nearby vehicles. At the same time, the calculated value is compared with the theoretical value. In this article, the theoretical formula for calculating the ignition time of vehicles near the fire source, is only applicable to conservative estimates of vehicles with the same level of fire and with no shelter between them. And it is not applicable to the calculation of the ignition time of upper and lower vehicles of the fire source. According to the calculation, this type of garage can not discharge heat rely on natural ventilation. It is necessary to exhaust smoke from the parking spaces in the same level as fire source, which are under greater impact, so as to control the development of the fire.