Fluoride molten salt has many advantages, such as high temperature stability, high thermal conductivity,large heat capacity,wide electrochemical window,low saturated vapor pressure and small neutron absorption cross section. It is an important functional material which has found widespread applications. The typical preparation and purification methods of fluoride molten salt, including vacuum dehydration, fluorination using ammonium fluoride, H₂-HF purification, electrochemical purification and reduction with metals, are introduced in detail. The mechanism and technical characteristics are analyzed for the different methods that are used to remove impure ions in molten salt. At the same time, the applications and progress of fluoride molten salts in nuclear energy, metallurgy, functional materials preparation, advanced energy storage medium, surface treatment technology, electronic chemicals, fine chemicals and molten salt battery materials are reviewed. The fluoride molten salts are mainly used as the nuclear reactor coolant, molten salt electrolyte, high temperature energy storage material and reaction medium. The existing problems in this area are also discussed. It is important to study and clarify the preparation and purification mechanism of fluoride molten salt, to explore the existence form and impurity migration nature in the process of fluoride purification, and to develop a new method for the purification of the molten salt to reduce its corrosion and cost.

Although many experimental studies were conducted on oil-gas transportation pipeline hydrate plugging mechanisms worldwide, there has always been a lack of systematic summary. According to the difference in experimental conditions, oil-gas transportation systems were firstly divided into oil-dominated systems, water-dominated systems(water systems and water-continuous systems), gas-dominated systems and partially-dispersed systems. Analyses show that there are many pipeline hydrate plugging mechanisms, including hydrate agglomeration and deposition, hydrate jamming and the separation of oil and water. For oil-dominated systems, hydrate agglomeration/jamming and hydrate deposition(film growth, wall adhesion and bedding) are the main plugging mechanisms. For water systems, hydrate particle bedding is the dominant plugging mechanism. For gas-dominated systems, hydrate agglomeration and stenosis caused by hydrate jamming are the main plugging mechanism. As for the main plugging mechanisms in water-continuous systems and partially-dispersed systems, there is no definite conclusion can be drawn and much work is still needed.Quantitative researches on droplet size distribution in annular flow, oil-water dispersion state, emulsion stability and non-emulsified free water are the focuses of hydrate plugging mechanism research in the future.

As an efficient heat exchanger, the plate heat exchanger(PHE) is applied more and more widely. Due to the complex mechanism of phase change convective heat transfer, the design of phase-change PHE is always a difficult problem. In this paper, the characteristics of condensation heat transfer and boiling heat transfer were summarized, the latest research progress of theoretical analysis, numerical simulation and experimental test of phase change heat transfer in plate heat exchangers were reviewed, and some published experimental correlations were listed. The influence of the operating parameters on heat transfer coefficient and the pressure drop of the plate heat exchangers was discussed. The results of some experimental correlations were compared and analyzed, and some different conclusions were also reviewed. In addition, the application of computer simulation technology in this research field was also introduced. Finally, the main problems and the future development directions in the study of phase change heat transfer in plate heat exchangers were pointed out.

The hazardous chemicals are always the key targets of national supervision for their potential great harm, and they are also difficult points for petrochemical enterprises to control. By analyzing the supervision system of the domestic and foreign hazardous chemicals, and summarizing the safety management requirements and information requirements of the storage, use and disposal of hazardous chemicals in petrochemical enterprises, Refining and Chemical Company of PetroChina organized the construction of a hazardous chemicals management system, and designed the function architecture, data architecture and application architecture of it in combination with sensor monitoring and GIS networking technology. The specific technical route of system development and implementation were illustrated, and then the system by using NET development platform was realized. This system was deployed in petrochemical enterprises of PetroChina, which met the management requirements of hazardous chemicals and achieved good application. The results showed that it can provide reference for petrochemical enterprises to carry out the construction and application of similar management system and strengthen the lifecycle safety management of hazardous chemicals. The system function can be enhanced by optimizing the on-site management of hazardous chemicals, collaborate with suppliers, and introduce advanced logistics technology.

The local neighborhood search methods depend greatly on the initial solution position and are usually subjected to the local optimal solutions. Therefore, an inverse gradient evolution algorithm with penalty is proposed in this paper. This algorithm employs a penalty positively related to the dwell time at the local optimal position to force the individual to move along the inverse gradient direction and then far away from the current local optimum. Meanwhile, to prevent 'rebound' phenomenon, tabooed neighborhood is introduced into the algorithm to prohibit the individual from moving back to its original position. As the filled functions are established by penalty in real-time, the mechanism of escaping the local optima in the proposed method is relatively deterministic rather than random in the heuristic methods, which improves the search efficiency for the individual. Finally, applying the algorithm to heat exchanger network synthesis problems, its effectiveness is verified by the typical 10SP1 and 10SP2 case studies. The obtained solutions are better than those in the literature, demonstrating the relatively strong ability of the proposed method to jump out of local optima.

Considering that the scheduling of blast furnace gas(BFG) system is crucial for energy saving in iron and steel industry, this study proposes a novel scheduling method for BFG system based on dynamic Bayesian network(DBN) and improved multi-objective differential evolution(IMODE) algorithm. On account of the dynamic characteristic of the BFG system and the output uncertainty of time prediction model, this study models the BFG system with the causality based DBN method. Simultaneously, the optimization target is that the gas cabinet reaches the desired value fast with a large margin for adjustment. When optimizing the scheduling schemes, the crowding distance of the particles is involved into the searching mechanism of IMODE algorithm to improve the searching precision. Furthermore, in view of the fact that the gas tank cannot run securely by adjusting a single user and the differences of adjustment ability of different users, a multi-user scheduling scheme method is proposed. In order to verify the effectiveness of the proposed method, experiments are carried out with the BFG system production data of a domestic steel enterprise. The results show that the proposed method is more effective than others for the scheduling of the BFG system.

Training sample selection is a key step to establish soft sensor models. According to traditional selection methods, the information of dependent variables cannot be used well. In addition, it is difficult to evaluate the impact of training samples on soft sensor models. To handle these issues, in the present paper, a new training sample selection strategy based on intelligent optimization algorithms was proposed. The objective function of our proposed method was combined with a loss function and a compression-ratio operator of training samples which can tune the direction of searching. The advantage is that it can make full use of dependent variables and the effectiveness of training samples in a certain soft sensor model. As a result, it can optimize the structure of selected training samples. The performance of our proposed methods was demonstrated by its practical applications on research octane number(RON)-near infrared(NIR) spectrum data set, which were selected from gasoline blending process. Besides, a diesel NIR spectrum benchmark data set were also provided. Based on these data sets, we analysis and discuss the impact of training samples on soft sensor model, some useful results were gained. Compared with traditional partial least squares method(PLS), locally weighted PLS, and several other modeling strategies, the proposed method was found to achieve good accuracy and robustness, it is very suitable for industrial application.

The performance test of the absorption refrigeration cycle with ionic liquid, 1-ethyl-3-methylimidazolium diethylphosphate[Emim] [DEP]-based binary working pairs[Emim] [DEP]+ H₂O and ternary working pairs LiBr+[Emim] [DEP] + H₂O were conducted in order to evaluate the refrigeration effects of this new ionic liquid-based working pairs. The experiment results showed that the ionic liquid-based working pairs[Emim] [DEP]+H₂O was capable of refrigeration. Compared with the working pairs LiBr+H₂O,[Emim] [DEP]+H₂O lowered the performance coefficient of refrigeration cycle due to its lower thermal conductivity and higher viscosity which led to absorbing water steam ability of[Emim] [DEP]+H₂O in absorber more weak under the same size of absorber. When the generation temperature and cooling water temperature were 90℃ and 30℃, respectively, the evaporation temperature was in the range of 10 to 15℃, the performance coefficient of refrigeration cycle varied from 0.16 to 0.28. In order to enhance the absorbing ability to water steam in absorber and consequently to real performance of absorption refrigeration cycle, small amount of solution LiBr+ H₂O was added into the[Emim] [DEP]+H₂O and constituted ternary working pairs LiBr+[Emim] [DEP]+H₂O,the experiment results showed that the performance coefficient of refrigeration cycle of ternary working pairs LiBr+[Emim] [DEP]+H₂O was superior to that of[Emim] [DEP] + H₂O, and varied from 0.17 to 0.34 when the evaporation temperature was in the range of 10℃ to15℃.

Multi-walled carbon nanotube (MWCNT)nanoparticles were added into distilled water with hydrophilic TNWDIS of nonionic-type as surfactant. In order to get the stable homogeneous dispersions of MWCNT-H₂O nanofluid, ultrasonic generator was used. Under the condition of 100Pa and adsorption, the effects of nanofluid for different mass fractions, particle sizes of MWCNT and different ratios between MWCNT&TNWDIS on static vacuum flash characteristics of ice-making were studied. The results showed that the addition of MWCNT can eliminate the stage of phase-change and shorten the cooling time at the stage of liquid phase. So the supercooling phenomenon appeared earlier. The 20-40nm MWCNT-H₂O nanofluid which the concentration ranges from 0.075% to 0.15% can be well-distributed by TNWDIS. When the concentration of MWCNT was 0.1%, the supercooling degree of water decreased by 62.2%, which reached the maximum reduction. The supercooling degree increased with the increase of particle size, while the flash evaporating rate remained at 40%. However, ice packing factor is varied nonlinearly. The optimal dispersive proportion of TNWDIS and 20-40nm MWCNT is 0.5:1. Under this dispersive proportion, the supercooling degree of 0.1% MWCNT-H₂O nanofluids remained at 2℃.

Flue gas turbine is the core equipment in the energy recovery system of catalytic cracking unit. In order to ensure the safe operation, it is necessary to solve the deposition problem of catalyst particles on the rotating blade surface. The influence of inlet air flow rate, concentration and particle size on the particle deposition on the rotating blade surface was studied. The results showed that the deposition quality decreases with the increase of the air flow rate. The smaller the particle size, the faster the deposition quality decreases. When the concentration is low, the deposition quality increases with the concentration increasing. While the concentration increased to a certain extent(10g/m³ under experimental conditions), the deposition quality did not vary with the concentration. In the same concentration, air flow rate and other conditions, the smaller the size of the inlet particles are, the greater the quality of deposition. Particles with size less than 40μm are more prone to deposition. Particles larger than 40μm are difficult to deposit on the blade surface. The experimental results provide a reliable basis for controlling the particle deposition.

Oman vacuum residues were separated into saturation, light aromatics, middle aromatics, heavy aromatics, light resins, middle resins, heavy resins, and asphaltene by liquid-solid chromatography method, and the hydrocarbon compositions and the molecular structure of each fraction were characterized. Meanwhile, solubility parameters were calculated by the group contribution method and the relation between properties and solubility parameter was correlated. The results indicated that the sulfur distribution of aromatic and resin fractions was relatively uniform, while the vast majority of N(85.05%), CCR(91.95%) and metal(99.85%) were mainly enriched in heavy aromatics, resins and asphaltene; the removal rate of metal(Ni and V) and CCR decreased markedly at the total component yield of 53.8% and 43.8%, respectively, which was important to guide solvent deasphalting process. From saturate to asphaltene, the density (ρ_i), molar volume(Vi) and solubility parameter(δi) increased. In addition, the δ_VR of Oman residue was 17.29 MPa^1/2, between light aromatics and middle aromatics. Compared to S, N, CCR, H/C ratio, density, f_A and R_T, excellent linearity between δ and lnM was shown and the correlation equation was δ=4.7282lnM-14.639.

In order to investigate the overpressure characteristics and flame behavior of gasoline-air mixtures explosion in a semi-confined space with double side branches structure, the explosion overpressure peaks in straight and bilateral branches pipes under different initial gasoline-air mixtures concentrations were studied. Semi-open plexiglass pipes were used to visualize the flame propagation behavior. Results showed that:①there existed three typical pressure peaks denoted as p₁、p₂ and p_max during the gasoline-air mixture explosions in the semi-open pipe and the magnitude of p₁ was just associated with the fracture constant of the polyethylene film at the pipe exit and p₂ was related to branch pipe pressure relief while p_max was affected by the intensity of explosion inside the pipe and flame acceleration. ②The branch pipe has an intensive effect on the explosion strength. With the increase of gasoline-air mixtures concentration, the strengthening effect firstly increases and then decreases, and the strengthening effect is most intense at the concentration of 1.4% to 1.8%. ③The flame occurs at the branch structure with significant bending and folding, which increases the flame area, increases the combustion rate, accelerates the heat transfer efficiency of the flow field, induces the sharp increase of explosion intensity, and at the same time, the flame propagation speed and the maximum flame front position are increased. ④The flame presents a "hemispherical flame——fingertip flame——planar flame——spray flame" morphology changes in the pipe containing the bilateral branch structure.

As a new type of hydrate control method and multiphase safe mixing method, hydrate slurry mixing infusion technology has attracted more and more attention. In this paper, the research of hydrate formation process, hydrate coalescence theory and deposition theory of hydrate particle tube wall are introduced in recent three years in China, and the future research direction is presented. The research conclusions of hydrate formation process in pipeline which are obtained by experiment under the condition of different pipe transportation media and pressure drop as well as the influence of inhibitor on macroscopic evolution of hydrate in pipeline and the conditions of plugging of pipeline are summarized. In the aspect of hydrate coalescence theory, two hypotheses including particle coalescence principle and hydrate induction principle are introduced and the research deficiencies are put forward. Because the hydrate coalescence theory cannot fully explain the phenomenon that the pipeline pressure drop will increase sharply when hydrate formation occurs, the theory of deposition of hydrate particles has been developed in recent years, but few studies have been done on the theory in China. The future directions of development are as follows. ① The coupling between hydrate growth process and the types of pipe conveying media, flow rate, pressure drop, water cut as well as the change of pipe fall and temperature in the actual engineering should be studied, and establish mathematical model;② The influence of adding new type inhibitor on the macroscopic morphology evolution of hydrate in pipeline under different conditions should be investigated as well;③ At present, there are two main hypotheses about hydrate coalescence:particle coalescence principle and hydrate induction principle, but there are some experimental supports for this two hypotheses. Therefore, the study of the mechanism of hydrate coalescence in the future should be focused on the distinction and relation between these two theories; and ④ In China, there is little theoretical research on the pipe wall deposition, thus the future should focus on this aspect.

Alkali/alkaline earth metals(AAEM) in coal can cause slagging and corrosion in a boiler or gasifier, while their catalytic effect has been confirmed for combustion and gasification. Thus, identifying the occurrence modes of AAEM in coal, revealing their roles in coal conversion processes and exploring the probability of transformation among different occurrence modes of AAEM are of great significance in investigation of approaches to alleviating or eliminating the slagging and corrosion of the apparatus and to strengthening their catalytic effects. In this paper, a critical literature survey was presented in the following aspects, including the occurrence modes and separation methods of AAEM in coal, and the mechanisms of apparatus corrosion caused by AAEM as well as catalytic mechanism for coal combustion and gasification, in which more attentions were paid on the possibility of transformation of AAEM in different occurrence modes. The results showed that ① AAEM in coal could be divided into water-soluble, ion-exchangeable, acid-soluble and insoluble by the sequential extraction method, but there were some shortages in the existing methods, which can be improved by screening extraction agent and standardizing operation process to achieve the purpose of accurate separation;② the roles of AAEM in coal conversion processes depended on their occurrence modes in coal, however, the relationship between the roles and occurrence modes of AAEM is not clear. A detailed study and further verification will be needed; ③ there were limitations to alleviate or eliminate the harmful effects of AAEM by some technical measures such as washing, acid washing, additives and blending coals; and ④ AAEM in different occurrence modes in coal could be transformed from each other. If the harmful forms of AAEM can be transformed into beneficial forms, it may lay the foundation for the development of an innovative technology for the clean and efficient utilization of high alkali coal.

The separation of phenolic compounds is one of the effective ways to realize the high value-added utilization of coal tar. The understanding of the distribution of phenolic compounds and their structure characteristics is favorable of the development of efficient separation methods. Aiming at the separation and purification of phenolic compounds, this paper reviewed three kinds of separation methods of phenolic compounds(alkali extraction method, solvent extraction and new methods) and introduced the progress of phenolic compounds purification. The advantages and disadvantages of different separation and purification methods were also compared objectively. Three kinds of identification methods(spectrophotometry, chromatography and nuclear magnetic resonance) were introduced systematically. This paper discussed the development trend of technology in this field, and pointed out that the analysis and identification of phenols needed to combine various advanced methods for analyzing its composition and structure in multi-level and all-round way. The selection of environment friendly and efficient extracting agent could be accelerated to promote the application of new extraction methods. The purification of phenolic compounds should be focused on developing the efficient purification processes of m/p cresol and mixed cresol, and strengthening the extraction of advanced phenols.

Although the solar energy and the air source heat pump are all clean and energy-saving, their performances are subject to weather conditions. In some conditions, they can't operate with higher efficiencies. If the solar energy and the air source heat pump is integrated, the new system can achieve the complementary advantages. From various the solar energy and the air source heat pump integration methods, the recent progresses of the integrated heating system of solar and air source heat pump were discussed in this paper. The characteristics of solar assisted ejector-compression heat pump, solar photovoltaic/thermal integrated dual heat source heat pump and other kinds of different integrated system were analyzed. The research indicated that the solar energy could improve the low temperature performance of air source heat pump, relieving frosting problem of air source heat pump. In turn, air source heat pump could compensate for solar instability and discontinuity defects. Therefore, the combination of solar energy and air source heat pump can improve the reliability and energy-saving ability. Finally, the inadequacies of existing research are analyzed and some suggestions for future research are proposed.

Molecular distillation is an efficient bio-oil separation technology. The wiped-film molecular distillation apparatus was employed to investigate the separation properties of the simulated bio-oil under different process conditions including distillation temperatures, distillation pressures and feed rates, respectively. Then, the response surface method was used to study the effects of multi-factors on the molecular distillation. According to ANOVA analysis, the F-value of 21.25 implied the model was significant. The concentration of the acid, the aldehyde and the ketone in the light fraction was set as the response value and the optimum condition of 69.83℃, 1498.31Pa and 5.54mL/min was determined. On this condition, the concentration of the acids, the aldehydes and the ketones was as high as 39.12%. Finally, the validation test of the simulated bio-oil was carried out under the optimum condition. The concentration of the target products in the light fraction of 38.96% was achieved, which was highly in accordance with the result from response surface method. The concentration of acid, the aldehyde and the ketone via molecular distillation increased from 28.50% to 38.96%, and the concentration of the phenols decreased from 37.50% to 25.14%.

The recycle of industrial and agricultural wastes is important for protecting the environment and conserving resources. The experiment of co-gasification of rice straw and sludge was performed in a bubbling fluidized-bed. The effects of gasification equivalence ratio(ER), material moisture content and sludge mixing ratio on gasification characteristics and tar yield were analyzed, respectively. The results showed that of the ER increased from 0.2 to 0.4, the content of combustible gas, the low heating values (LHV) of syngas and gasification efficiency increased slightly at first and then decreased gradually. The gasification efficiency reached the maximum of 53.8% when the ER was 0.25; Tar yield decreased as the ER increased. When the material moisture increased from 5% to 20%, all the combustible gas content dropped, so did the LHV of syngas, gas yield and gasification efficiency; Tar yield increased first and then reduced. When the sludge mixing ratio increased from 0 to 30%, the concentration of H₂ was essentially unchanged, while the content of CO and CH₄ increased at first and then reduced. The LHV, gas yield and gasification efficiency reached the best when the sludge mixing ratio was 20%; Tar yield decreased at first and then increased slightly.

The particle size distribution(PSD) of active materials is one of the important performance parameters of the lithium ion battery electrode. Based on a multi-particle model with different particle size distributions, the electrochemical performance of the lithium ion battery was simulated and analyzed during its discharge process. The effects of different particles on the whole discharge process were illustrated, and the interactions between particles were discussed. Results indicate that the performance of Li-ion battery was greatly influenced by the PSD. In the early stage of the discharge, the intercalation reaction of lithium ion occurs mainly on the particles with small size, which are then saturated in the late stage. The particle surface reaction is transferred from small particles to large particles because they have more internal vacancies. Therefore, in the battery manufacturing process, the size of the electrode active material particles should be as uniform as possible, which can reduce the polarization caused by the nonuniform particles.

Deep eutectic solvents are also called deep eutectic mixtures or low transition temperature mixtures. As a novel class of ionic liquid analogues, deep eutectic solvents have become more and more popular in many fields due to their unique physical and chemical properties, low cost, simple preparation process, non-toxicity, negligible vapor pressure, biodegradability, which are also tunable to achieve specific functionality by adjusting their constituents and compositions. In this paper, the common hydrogen bond donor and acceptor units as well as the classification of deep eutectic solvents are introduced. And the latest research progress on the formation mechanism of deep eutectic solvents and their applications as extracting agents, solvents and catalysts in the field of extraction and organic reaction, such as esterification, Fridel-Crafts, cyclization, condensation and multicomponent reaction are summarized. Also, the existing problems and solutions in developing deep eutectic solvents are discussed. Deep eutectic solvents will be a promising new generation of solvents and catalysts thanks to their adjustable structures and functions.

When the coal-fired power plant operates at low loads, the low temperature of the flue gas entering the denitrification device will result in the formation of ammonium hydrogen sulfate on the catalyst, decreasing its activity and performance. The formation mechanism of ammonium hydrogen sulfate and its effects on the SCR catalyst are analyzed. Following that, this paper suggests that reducing the concentration of SO₃ in flue gas is the key to slow down or even to avoid the poisoning of SCR catalyst by ammonium hydrogen sulfate. The methods to reduce the concentration of SO₃ in denitrification unit and other units are reviewed and analyzed from the aspects of process and catalyst design. And the regeneration methods for the poisoned catalyst and their advantages and disadvantages are also reviewed and discussed. We proposed several important research directions in the future to prolong the working life of the catalyst:①spraying alkaline absorbents to reduce the SO₃ concentration before the flue gas goes into the denitrification unit to contact with NH₃;②making a rational design of the composition and structure of the catalyst, since the SCR catalyst in the denitrification device also oxidize SO₂ into SO₃. However, despite of various methods to avoid catalyst poisoning, it is difficult to remain high activity for the SCR catalyst running under low temperature. To develop the regeneration method and build the device are also of importance. One promising way is to increase the catalyst temperature to decompose the ammonium hydrogen sulfate and regenerate the catalyst in operation.

Molybdenum based catalysts of Mo/SBA-15 and KMo/SBA-15 were prepared via the incipient-wetness impregnation method, with high surface area SBA-15 as the support. N2 adsorption-desorption, XRD, Raman and XPS were carried out to investigate the effect of K on the CH₃SH synthesis progress. Dynamics study showed that the CO conversion and CH₃SH selectivity were greatly improved when K was added, and the selectivity of CH₃SH over KMo/SBA-15 reached 62% under high H₂S concentration, higher than other reported catalysts. Based on the Raman and XPS results, the MoS₂ content increased with the addition of K.

The emergence of O₃ was inevitable during the VOCs oxidation by plasma assisted catalysis. In order to study the mechanism of VOCs oxidation with the formation of O₃ byproduct during plasma, different catalysts (SBA-15, FeO_x/SBA-15, FeO_x-AgO_x/SBA-15) were placed inside and outside the plasma zone, and then the O₃ concentration was measured and the effect of the catalysts on the toluene degradation was studied. The results showed that the O₃ and ΔO₃ were significantly increased when the catalysts were put inside the plasma zone, while the O₃ concentration decreased when the catalysts were put outside the plasma zone, close to the case of bare plasma. The toluene removal efficiency improved, and the CO₂ selectivity decreased. At the same time, O₃ concentration gradually decreased with the increase of toluene concentration when only plasma were used. However, when the catalysts were put inside the plasma zone, the O₃ concentration increased under the toluene concentration of 410mg/m³ and 615mg/m³, but the catalysts has little effect on the O₃ concentration when the toluene concentration further increased.

This paper reviewed the latest development of novel adsorbents for dibenzothiophene (DBT) removal and their corresponding adsorption mechanisms. Herein we focus on the research progress of different new adsorbents such as metal organic framework materials(MOFs), molecularly imprinted polymers(MIPs), graphene based materials, active carbon based materials(AC) and mesoporous materials. Then the influence of the surface modification of various materials on the adsorption capacity was discussed from the perspective of desulphurization mechanism. Furthermore, we analyzed the advantages and disadvantages of these adsorptive desulfurization materials which may provide a direction for the exploration of efficient adsorbents for the removal of DBT. The main problems that impede the large-scale industrial application of the adsorbents in the removal of DBT from fuel oil are their recycling, the contamination with fuel oil and the loss caused by the separation. Therefore, the selection of the adsorbents, their modification, and the mechanism investigation will be the main topics for DBT removal by adsorption.

The flexible pressure sensor, a core device of wearable electronics, has attracted wide attention in recent years. In this paper, the research development of carbon materials based on high-precision flexible pressure sensor is reviewed, including the sensing mechanism, main materials (substrate materials, active materials and electrode materials), factors influencing the performance and performance optimization methods as well as the latest applications in the human body movement and health monitoring. The flexible pressure sensor based on the carbon micro-nanomaterials, such as carbon black, graphite, carbon nanotubes and graphene, as the sensing active material is designed, according to the piezoresistive and capacitive sensing mechanisms. It is characterized by high sensitivity, high linearity and fast response; moreover, its performance can be improved through the control over the content or structure of carbon material. However, low cost, good performance, low power consumption and self-driving function have still been the challenges in the development of flexible sensor. Development of new sensing mechanism, functionalization of new materials and integration of flexible devices will be the future development direction of flexible sensor.

In the past few years, the development of organic-inorganic hybrid perovskite solar cells (perovskite solar cells) grew rapidly, the power-conversion efficiency(PCE) in small area devices had been increased from 3.8% to 22.1%. Herein, the advantages and disadvantages of the perovskite solar cells in terms of physicochemical properties, structures, and the preparation methods of perovskite films are reviewed thoroughly in this paper. At first, the developments of perovskite solar cells and the structural evolution of the mainstream devices were briefly introduced, emphatically described the fabrication methods of the light-absorbing layer perovskite films, which were prepared by one-step spin-coating processing, two-step sequential deposition(in situ dipping method and two-step spin-coating deposition), and dual-source vapor deposition. Then, the key factors of the perovskite film formation and the micro-topography control technology were introduced and discussed, especially focused on the effects of growth of large crystals adjusted by solvents, compositions of precursors, mixed lead salts, additives, and coarsening of crystal growth on the efficiency of the perovskite solar cells. Finally, existing problems and future work were summarized, which includes precisely controlling the chemical composition of perovskite film, overcoming reproducibility issues and increase product yield, understanding perovskite crystallization process and work mechanism of device, preparing large-area perovskite thin films and perovskite solar modules, improving the long-term stability of the device, and developing environmentally friendly lead-free or lead-less perovskite solar cells.

Mesoporous materials are usually prepared with the petroleum derived surfactants as templates, which are non-renewable resources; the adoption of these templates does not match the concept of sustainable development. The biomass templates have been extensively investigated owing to its wide availability of raw materials, low toxicity, environmental friendlines, and other advantages. This work reviewed the recent research progresses in synthesizing the mesoporous materials with biomass templates, such as fatty acids and their derivatives, amino acids, sugars, lipids and so on. The studies on the application of sugars as template in the preparation of mesoporous materials were more than other biomass templates. The conditions of preparing the mesoporous materials with different kinds of biomass templates and the removal methods of biomass templates were briefly introduced. It was concluded that the operations of synthesizing the mesoporous materials with biomass templates were simple and the biomass templates could be easily removed. At the same time, the characteristics of structures and properties of mesoporous material obtained and their applications were summarized. It was pointed out that the purification of the biomass template at the low cost, the green method to remove the biomass templates, and more studies on the relationship between the structure and composition of biomass templates and the structure and properties of mesoporous materials are the main directions of future development.

Layered double hydroxides (LDHs) have attracted much attention as a low cost 2D inorganic material with positive charge, highly tunable structure and two-dimensional reaction space. The synthesis of LDHs with good dispersion, narrow size distribution and tunable structure and composition remains a major challenge. In addition, to meet the requirements of practical applications, other functional components need to be assembled with modified LDHs to form functional LDHs materials, which brings significant conceptual challenges to their structural design and preparation strategies. Therefore, this paper focused on the controllable synthesis, surface chemical modification and functional composite materials of LDHs, and summarized the contributions of researchers on the design and preparation of functional LDHs. The characteristics and functions of the functionalized LDHs composites in different fields were also analyzed. Finally, the innovation of structural design and simplification of synthesis scheme were proposed to be the research focus on designing functional LDHs composite in the future.

The polycaprolactone (PCL), isophorone diisocyanate (IPDI), 2,2-double bromine(meth)-1,3-propanediol, sodium azide (NaN₃) were used as raw materials to synthesize polyurethane pre-polymers with azide groups; the 1,1,3,3-tetramethyl guanidine (TMG), 3-bromine propiolic were employed to synthesized the five-replaced guanidine alkyne (TMG-Al), then an environmental contact-killing antibacterial activity waterborne polyurethane was prepared using click chemistry as connection strategy. The chemical structure of small molecular monomers was characterized by Fourier transform infrared spectroscope (FTIR), nuclear magnetic resonance spectrum(NMR); according to bacteriostatic ring experiment, the contact-killing and non-penetration activity was verified and an new synthesis method was developed for the field of contact-killing antibacterial research. The result of antimicrobial polyurethane showed that the effect of killing gram negative bacterial (E.coli) and gram positive bacterial (S.aureus)was significant and the antibacterial rate was 99.9% when imported TMG-Al by mass fraction 5%.

The modified Hummers method was used to prepare graphite oxide (GO) through freeze drying. The sulfur-nitrogen co-doped graphene samples were then synthesized by one-step hydrothermal method using thiourea as dopant and reductant, with mass ratios of GO to thiourea of 1:10, 1:20, 1:30, 1:40 respectively. The microstructure and morphology of the as-produced graphene were characterized by X-ray diffraction, field emission scanning electron microscope, Raman spectroscopy, X-ray photoelectron spectroscopy and nitrogen adsorption-desorption analysis. The electrochemical performances of the samples were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge (GCD) technology. The results showed that the sulfur-nitrogen co-doped graphene had the highest sulfur content of 1.86% and nitrogen content of 7.73%, with a specific surface area of 175.8m²/g and the pore sizes were narrowly distributed in between 3-5nm when the mass ratio of GO:thiourea is 1:30. At 1A/g current density, SNG had a specific capacitance of 197.2F/g, and only 10% were lost after 2000 charge and discharge cycles.

The introduction of nanoparticles into polymer with conventional methods could only produce a few nanoparticles in the polymer. In order to prepare micro-nano composite films with high content of nanoparticles, a new method based on imprinting process is proposed. The PDMS is used as the polymer material to fill the cavities of the silicon template by imprint pressure, and the SiO₂ nanoparticles are coated with PDMS to form a micro-nano composite films with high content of nanoparticles. The morphology and contact angle of the prepared films are analyzed by scanning electron microscopy, optical microscope and contact angle measuring instrument, respectively. The results show that the template with large void ratio is favorable for the filling of the polymer, while proper polymer thickness is beneficial for the uniform distribution of the nanoparticles in the polymer. The dispersibility of the nanoparticles is significantly increased with the decrease of polymer viscosity. The prepared film has superhydrophobic properties, and the static contact angle is 151°.

Barium hydroxide octahydrate, as a phase change material used in medium-low temperature, is widely used in industries due to its high stability and high latent heat. However, there's serious supercooling during its phase change process. Based on the scientific method and Edison method, experiments for two frequently used kinds of nucleating agents including barium salt and three others were conducted. The addition of 4% of Ba(OH)₂·H₂O as the nucleating agent showed the best supercooling degree of <1℃ with little influence on thermal properties of main material, while other nucleating agents either were not stable or increased the degree of supercooling. The latent heat and the phase change temperature are 267.7kJ/kg and 77.9℃ respectively as determined from the DSC test. After 100 times cyclic experiments, the phase change temperature and phase change latent heat of the composite PCM approximately remained constant, only changed 0.63% and 3.81% respectively, indicating the thermal physical properties are stable. Therefore, 4% Ba(OH)₂·H₂O can be considered as an ideal nucleating agent to be applied in industry.

A low temperature phase change material with the disodium hydrogen phosphate (Na₂HPO₄·12H₂O) as the main energy storage material was developed. The property of the Na₂HPO₄·12H₂O was modified by adding nucleators, such as nano Al₂O₃, nano TiO₂, nano-graphite powder, multi-walled carbon nanotubes (MWCNTs), and the polymer dispersant polyacrylic acid sodium(PAAS). The results showed that the adding of MWCNTs would reduce the super-cooling degree of the Na₂HPO₄·12H₂O while destroy its phase change characteristics. The super-cooling degree decreased by 40.7% after adding 3% (mass fraction) nano Al₂O₃, 44.6% by adding 4% nano TiO₂, and decreased by 62.3% after adding 4% nano-graphite powder. Compared with 3% (mass fraction) nano Al₂O₃ composite phase change material, the concentration of PAAS had no effect on the supercooling degree. Comepared with 4% nano TiO₂ composite phase change material, the minimum supercooling degree was 3.2℃, which decreased by 76.1% by adding 4% PAAS. Comepared with 4% nano-graphite powder composite phase change material, the minimum supercooling degree was 1.2℃, which decreased by 90.7% by adding 2% PAAS. It was found that the three elements composite phase change material had good thermal reliability by the cyclic experiments.

Poly aluminum titanium sulfate (PATS), an inorganic composite polymer coagulant, was prepared with aluminum sulfate and titanium sulfate. Ferron-complexation timed spectrophotometric method, infrared spectroscopy, X-ray diffraction, scanning electron microscopy and energy were applied to analyze the morphology of Al and the structure, morphology and the composition of PATS. The optimum synthesis conditions were obtained by single factor experiment as:reaction temperature was 50℃, the molar ratio of n(Ti)/n(Al) was 0.3:1 and the molar ratio of n(OH)/n(Ti+Al) was 0.3:1. Morphological analysis showed that reaction temperature, and the ratios of n(Ti)/n(Al) and n(OH)/n(Ti+Al) had influence on the morphology distribution of Al, and the latter are more significant. With the increase of n(OH)/n(Ti+Al), the content of Al_a decreased gradually, while the content of Al_b and Al c increased gradually. With the increase of n(Ti)/n(Al), the results are totally oppsite. With the increase of reaction temperature, Al_a is dominant, and its content changed in the range of 78.94%~85.49%, showing a trend of decreased first and then increased which was also observed for Al_b, however the content of Al c was increasing first and then decreasing with reaction tempeature. The results of infrared spectroscopy and X-ray diffraction confirmed that the polymerization of aluminum sulfate with titanium sulfate occurred, with macromolecule polymer formed. The scanning electron microscopy showed that the morphology of PATS clusters were network structure, which was beneficial for the adsorption bridging and netting sweeping, and enhanced the coagulation performance of PATS.

For complex systems with multiple influence factors, reliable mathematical models could be obtained with few experiments by using the uniform-design method without decreasing interaction-sensitivity analysis, which can ben then used to derive the opitmal process conditions. A U₁₂₊ (6^6) uniform-design test scheme was employed to investigate the optimum process conditions for preparing nano-alumina-precursor by microemulsion method. According to the experimental results, the mathematical model for relationship between the particle size of nano-alumina and the 5 factors of the concentration of aluminum salt, the precipitant concentration, the reaction temperature, the volume ratio of surfactant to cosurfactant, and the volume ratio of oil to surfactant, repsectively, was established. By using the mathematical model established, the optimum process conditions for preparing nano-alumina precursor were given. The α-Al₂O₃ powder was then obtained by calcination at 1180℃ from the nano-alumina precursor preprared under the optimum process conditions. For the α-Al₂O₃ powder, the primary particle shape was rod, the primary particle size was about 30nm, and the secondary particle size (D₅₀) was 760nm.

A novel, simple and efficient method were reported to prepare polystyrene microspheres in foam phase. The key step of the method is that oil droplets were entrained into the foam phase, which was then driven to separate the phases to form porous structures through evaporation of volatile solvent at evaluated temperature. The results showed that the pore morphologies and the particle sizes were influenced by the ratio of polystyrene to porogen (R_-PS/HT), the PVA concentration and the agitation speed. When R_-PS/HT was extremely low, the internal structure of the microspheres became hollow. The particle size of the polystyrene microspheres decreased from 52μm±23μm to 23μm±20μm by increasing the PVA concentration from 1% to 3% and that decreased from 107μm±40μm to 45μm±20μm by increasing the agitation speed from 300r/min to 700r/min respectively. In addition, the porous morphologies were different with different foaming conditions. The reported method also showed a higher yield than the conventional methods of preparing the porous polymer microspheres in water system, especially when the ratio of oil/water phase is more than 1.

A new palladium-free activation technology for ABS plastic electroless copper plating is proposed. The plastic substrate is pretreated, and then placed in an activating solution prepared by mixing copper sulfate and sodium hypophosphite for 30 minutes. The plastic substrate is dried to form an activation layer at the surface, which is then uniformly scanned with a laser to allow the hypophosphite ions to be reduced into catalytically active copper particles. The effects of the formation of the activating solution and the laser parameters on the activation are studied. The parameters are optimized by using the orthogonal test. The microstructure of the coating is observed by scanning electron microscope. The energy spectrum of the substrate after laser activation is analyzed. Impact test is processed for coating binding detection. The results show that when the concentrations of copper sulphate and sodium hypophosphite are 10g/L and 30g/L respectively, and the laser spot diameter is 2mm and the scanning rate is 2.2mm/s, the coating completely covers the substrate and the surface of the substrate is uniformly coated with copper particles, showing compact microstructure and good binding.

Recently, microbiological biogas upgrading with external hydrogen as electron donor attracts researchers' attention for its mild reaction condition and less by-products. The hydrogen gas-liquid mass transfer might be the limiting factor, determining the development and application of this technology. Application of different reactors was found to affect the growth and distribution of hydrogenotrophic Methanogens, the contact way to the substrates and gas-liquid mass transfer rate, thereafter it might influence the process stability and conversion efficiency. In this paper, the reaction mechanism, the basic characteristics of microbial community distribution and operation mode were introduced. The main requirements for the reactors were analyzed. Reactor configurations such as continuous stirred tank reactor, up-flow anaerobic sludge blanket, biofilm reactor and their application were summarized. Finally, suggestions and perspectives were proposed for the further research of the technology and reactor.

Saccharomyces cerevisiae has been engineered as a cell factory for producing terpenoids. Acetyl-CoA is a basic precursor for terpenoid synthesis, but its insufficient supply in cytoplasm may result in a lower yield of desired products. The regulation of acetyl-CoA synthesis is an important means to construct high-yield synthetic pathway for target terpenoids. Therefore, this paper illustrates an important central carbon metabolism molecule acetyl-CoA, which is involved in the metabolism of four different organelles, including nucleus histone acetylation, cytoplasm pyruvate dehydrogenase branch, mitochondria tricarboxylic acid cycle, and peroxisome glyoxylate shunt. The metabolic engineering strategies to improve the content of acetyl-CoA, include strengthening endogenous pyruvate dehydrogenase branch, introducing heterologous acetyl-CoA synthetic pathway with lower ATP input requirement, enhancing CoA synthesis and mitochondrial regionalization of acetyl-CoA, which may be valuable for the efficient production of terpenoids in Saccharomyces cerevisiae.

Escherichia coli (E.coli) has intricate pyramid-shaped hierarchical regulatory networks regulated by regulators. The auto-regulation, co-regulation, and cross-talk regulation among regulators further complicate this regulatory network. Microbes can quickly respond to transitory environmental changes and optimize their metabolism to adapt to new conditions by modifying this intricate and efficient transcriptional regulatory network. In recent years, more and more researchers pay attention to engineer regulators of E. coli to improve its stress tolerance. This paper summarized the regulators of E. coli and their engineering methods, and reviewed the current state-of-the-art stress tolerance improvement with E. coli induced by rewriting its metabolic network through regulator engineering. While current regulator engineering mainly focuses on limited global regulators, novel engineering tools are needed to be developed and more regulators should be mutated for their corresponding genotype-phenotype analysis for further robust strain construction.

Microorganisms are important components of microbial electrolytic cells. It is important to study the community structure of the anode biofilm in the microbial electrolysis cell for the performance improvement, especially the special functional flora, such as exoelectrogen, hydrogen bacteria, methanogen and antibiotic resistant bacteria. Four kinds of MECs have been studied in this paper:MECs without chemical medicine (MECs), MECs with methane inhibitors (B-MEC), MECs with sulfamethoxazole (S-MECs), and MECs with a mixture of sulfamethoxazole and methane inhibitors (BS-MECs). The variation of species and community structure of different functional bacteria were analyzed. The results showed that microbial electrolysis cell system contained abundance exoeletrogens (3.97%-5.51%) and hydrogenogens (0.77%-1.35%). These bacteria groups guaranteed the efficient operation of the electrochemical system. In addition, a large number of antibiotic resistant bacteria appeared (2.67%-4.33%). The studies have shown that microbial communities could survive in the presence of antibiotic and they are essential to the microbial degradation of antibiotics.

A method of laccase immobilization was developed by ZrO₂ synthesized via biomineralization, which was prepared by encapsulating laccase in the zirconia nanoparticles with the lysozyme as the inducer, and the recovery rate of enzyme activity was 59%. Field emission scanning electron microscope (FESEM), energy dispersive spectrometer (EDS), and thermal gravimetric analyzer (TGA) were used to characterize ZrO₂ nanoparticles before and after the enzyme immobilization. The results proved that laccase was immobilized in ZrO₂ successfully and lysozyme was not only induced the formation of zirconia but also acted as a biological template encapsulated by ZrO₂. Enzymatic properties of immobilized laccase by biomimetic synthesis were also explored. The optimum pH and temperature of immobilized laccase were 3 and 70℃, respectively. Compared with free enzyme, the pH and temperature stability of immobilized laccase were significantly increased. The activity of the immobilized laccase was 95% of the original activity after storing for 30 days at 4℃, and the activity was still 60% of the initial enzyme activity after recycling 5 times. Moreover, the immobilized laccase was used in the decolorization of malachite green and the experimental result showed that the decolorization rate of the malachite green was more than 95% within 6h. Additionally it proved that the immobilized laccase decolorized malachite green by both of adsorption and degradation effects through the UV-visible spectroscopy analysis.

The application of the chitosan in flocculation is limited by its poor water solubility and low charge density. Chemical modifications of the chitosan can improve its water solubility and flocculation performance. The formation of Schiff base (B-CTS) by the chitosan and the benzaldehyde protects the amino group of the chitosan. Then B-CTS is reacted with the succinic anhydride to synthesize succinyl chitosan (SACTS) and further reacted with dimethyl diallyl ammonium chloride (DMDAAC) to synthesize succinyl chitosan quaternary ammonium salt (SAQCS). The structure and morphology of SAQCS were characterized by FTIR, 1HNMR, XRD, and ESEM. The effects of initiator dosage, monomer ratio, reaction temperature and reaction time on the cationic degree of SAQCS were discussed. The results showed that the optimum conditions were as follows:the initiator dosage was 2%, the m(DMDAAC)/m(SACTS)=5.4, the reaction temperature was 70℃, and the reaction time was 7h. Under those process conditions, the cationic degree of SAQCS was 42.26%. The flocculation experiment of SAQCS, CTS, CPAM and Kaolin simulated wastewater was carried out. The effects of H, dosage and temperature on flocculation were investigated. The results showed that the turbidity removal rate of supernatant was above 96% after flocculation when the flocculation conditions were pH=2-5, the dosage was 3-9mg/L, and the temperature was 25-50℃.

To increase the rate of gas transmission, meet seasonal variety and operation safety, a novel drag reducing agent (DRA), bis(N,N'-di-n-hexyl-vinylamine)-1,4-divinyl-piperazine disuccinate (BHVVPS), was synthesized by amines and acetaldehyde. The structure of BHVVPS was characterized with Fourier transform infrared spectroscopy (FTIR) and elemental analysis (ELA). Film-forming property and stability were assayed by scanning electron microscope (SEM), electrochemical method. And drag reduction was measured by the loop test. The results of FTIR and ELA tests indicated that the product was the target compound. The BHVVPS sprayed on the surface of the steel sheet formed a dense protective film, which decreased roughness of the steel. In electrochemical impedance test, the DRA formed two capacitive arcs successively from high frequency region to the low. With the BHVVPS, self-corrosion potential was increased by 0.214V while self-corrosion current was decreased by 0.87×^10-5A. In the loop test, the average drag reduction of BHVVPS was 9.9%, which was maintained above 8.0% for 60 days. The DRA synthesized possessed good film-forming property and stability. And the additive can reduce the roughness and possessed good drag reduction.

Bipolar membrane electrodialysis(BMED) as an advanced separation tool can effectively generate acid and base from its corresponding salts, respectively. Currently, the application of BMED for valorization of industrial high-salinity brine becomes a hot topic due to its technological superiority. However, some difficulties restrict its real practical application. In this paper, we comprehensively reviewed the application status of BMED for industrial high-salinity brine valorization in recent years and systematically discussed three critical barriers including the technical barrier associated to acid-base concentration and purity, techno-economic barrier related to process cost and economic barrier for investment cost, which hindered the large-scale industrial application of BMED technology. In view of these barriers, the further research and development of BMED technology is suggested which should focus on the reduction of bipolar membrane cost and elimination of co-ion leakage and water migration through ion exchange membrane. Presently, the reuse of prepared acid and base solution in the system process is strong recommended due to low acid-base quality as commercial product. Furthermore, this reuse process can decrease the expense of acid-base outsourcing so as to create extra economic benefit to offset the high investment cost of BMED technology.

Chemical-looping combustion (CLC) is a promising technology with inherent CO₂ separation. A novel configuration with a two-stage fuel reactor for CLC was proposed in this paper. Hot experiments were performed with hematite as oxygen carrier and sewage sludge as fuel in this CLC unit. The total continuous operation time was more than 8 hours under stable condition. The effects of fuel reactor temperature (800-900℃) and fuel feed rate (300-600g/h) on chemical looping combustion of sewage sludge were investigated. The results showed that FR-S1 had a larger oxygen carrier inventory and the pressure fluctuation in the downcomer was extremely stable during the steady operation period. The design of two-stage fuel reactor was beneficial to improve the carbon conversion efficiency of the whole system. There was an increase in the carbon conversion efficiency and carbon capture efficiency with the rise of fuel reactor temperature. Oxygen demand was always less than 10%. Higher sewage sludge feed rate resulted in the decrease of carbon conversion efficiency and lower fraction of CO₂. XRD analysis of oxygen carrier extracted from the both fuel reactors showed that oxygen carrier in FR-S2 had more Fe₂O₃ compared with that in FR-S1 and thus led to higher reactivity.

CuO-modified red mud oxygen carriers (Cu0.5RM1, Cu1RM1) were prepared by impregnation method and characterized by SEM-EDS mapping and XRD. The reactivity of red mud oxygen carrier in chemical looping combustion (CLC), with waste activated carbon (WAC) as raw material, was evaluated in a high-temperature bench fluidized-bed reactor and thermogravimetric analyzer (TGA). The results of SEM-EDS mapping showed that impregnation method was a desirable approach for preparing quantitative CuO-modified red mud oxygen carriers. CuO-modified red mud oxygen carriers were demonstrated to act as both CLC oxygen carrier and chemical looping with oxygen uncoupling oxygen carrier. Furthermore, WAC conversion rate and CO₂ concentration were significantly enhanced in comparison to pure red mud oxygen carriers. Additionally, it was found that Cu1RM1, due to the higher CuO loading, performed higher reactivity than Cu0.5RM1. Under the optimum temperature of 875℃, the CO₂ average concentration of 92.9%, the combustion efficiency of 93.0% and the residence time (t₉₅) of 28min were achieved. Moreover, Cu1RM1 had a good stability during the 10 redox tests.

In the manufacturing process of ion-exchange membrane caustic soda, trace iodide ions in the brine are oxidized during the electrolysis process into iodate ions or periodate ions which react with sodium ions, barium ion, calcium ion and magnesium ion in the brine to form precipitates, causing the membrane congested, the service life of the membrane shortened, electrolytic current efficiency reduced, and the voltage raised. Therefore, organic amine adsorbent for iodide was prepared by sol-gel method to study the dynamic adsorption removal performance and adsorption column recycling performance of trace iodine ions in sodium chloride solution. The results showed that the content of iodine ion in salt water was dropped to below 0.2mg/L after the adsorption column treatment, and the performance of the for the brine was between 3.0L/g to 3.6L/g when the quantity ratio of iodide ion and hydrogen ion was 1:2, the material liquid velocity was 6.4mL/(g·min), iodine ion content was 10mg/L,Na₂CO₃ elution content was 0.01mol/L, and cycle index was five times. Furthermore, the influence of the coexisting ions in the salt water on the iodide removal performance was investigated. The results showed that coexisting Br^-, SO₄^2-, Mg²⁺, and Fe²⁺ caused handle brine volume of the adsorption column decreased. Therefore, the removal treatment of iodide from brine should be conducted after calcium, magnesium, and iron removal treatments to ensure the iodine adsorption column efficiency.

The method of continuous determination of gold, silver and palladium in copper anode low grade copper slag was established and compared with the fire test method. First, the copper anode low grade copper slag was digested with nitric acid+EDTA+tartaric acid to obtain a digestion solution containing silver, palladium and a small amount of gold. The effects of nitric acid, EDTA and tartaric acid dosage on digestion were investigated. The results showed that the digestion was the best when the dosage of nitric acid, EDTA and tartaric acid were 30mL, 3mL and 1.5g, respectively. Then, the residue was subjected to secondary digestion with aqua regia to obtain a digestion solution containing gold and a small amount of silver and palladium. The effects of aqua regia dosage on digestion were investigated. The results showed that the amount of aqua regia required to complete the digestion was 15mL. Finally, the contents of gold, silver and palladium in digestion solution were determined by flame atomic absorption spectrometer. The relative standard deviations of Au, Ag and Pd in the copper anode low grade copper slag were less than 1% (n=10), and the recoveries were between 95.57% and 98.70% by this method. The experimental results are accurate, reliable and reproducible, which is consistent with the results of fire test method.

The MIL-101 photocatalysts were prepared by solvothermal synthesis method using chromic nitrate nonahydrate, terephthalic acid and hydrofluoric acid as precursors. The structures of the samples were characterized by X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-vis), fourier transform-infrared (FTIR), Brunauer-Emmett-Teller (BET), scanning electron microscope (SEM) and transmission electron microscope (TEM) measurements. The orientationasl separation and photocatalytic reaction of Cr(Ⅵ) and RhB in Cr(Ⅵ)-RhB combined pollution on MIL-101(Cr) were investigated. Furthermore, the synergetic treatment mechanism for the combined pollution was discussed. The results demonstrated that this photocatalyst exhibited higher treatment efficiency for Cr(Ⅵ)-RhB combined pollution than for single Cr(Ⅵ) or RhB under ultraviolet light irradiation. Meanwhile, because of the structure of MIL-101, the target pollutants of Cr(Ⅵ) and RhB with different molecular diameters can be directionally separated, and the oxidation of RhB was synchronized with the reduction of Cr(Ⅵ).

The water content in Chinese medicine residue was analyzed, and the mechanism of the dehydration of the Chinese medicine residue was analyzed. The characteristics of the Chinese medicine residue and the dehydration process of the belt filter press were used to transform the distributing device of the filter press. Two-stage feed screws were increased, improving the filter effect, making it suitable for Chinese medicine residue dehydration test. The amount of material handling was increased, the phenomenon of flash material was reduced, the solid content of sewage was reduced, the labor intensity of operating personnel was reduced. The influence of the different dehydration sections, pressure, belt speed of the filter press and the initial moisture content on the dewatering effect was studied by using the control variable method. The test results showed that the greater the initial water content of the material, the greater the dehydration rate of the different dehydration section, the greater the water content of the filter cake. The effect of the first grade dewatering roller on the material dehydration is the biggest, and the wedge dewatering section has the least effect on the material dehydration effect. The effect of the grade Ⅰ dewatering roller on the material dehydration is the biggest, and the wedge preloading section has the least effect on the material dehydration effect. The initial moisture content of Chinese medicine residue is not easy to exceed 80.16%. The gradeⅠ dewatering roller pressure selection between 0.2MPa and 0.6MPa is more appropriate. When the belt velocity is in the range of 0.3-0.5m/s, the moisture content of the filter cake is between 65% and 66%, and the dehydration effect is better.