The intrinsic flame retardant mechanism of bio?based epoxy resin containing pyridazinone structure was explored through resin ablation experiment, scanning electron microscope,X?ray photoelectron spectrometer,thermogravimetry?infrared simultaneous thermal analyzer,and other characterization methods.The results show that compared with the most commonly used petroleum?based bisphenol A epoxy resin, the resultant bio?based epoxy resin is more likely to form a large amount of intumescent carbon layer structure during combustion and release a large amount of non?combustible gases such as CO₂ and NH₃ with less combustible gases.The intrinsic flame retardant bio?based epoxy resin containing pyridazinone structure exhibits a condensed phase?gas phase synergistic flame retardant mechanism. This study provides new ideas for constructing high?performance intrinsic flame retardant epoxy resin.

In recent years, the global market demand for pressure?sensitive adhesives has shown a steady growth trend. The market demand has reached about 3.5 million tons in 2021, and the estimated size of the global pressure?sensitive adhesive market in 2025 is ＄10 billion. Amid the development of pressure?sensitive adhesive technology and the increase in the application demand for pressure?sensitive adhesives, functionally modified pressure?sensitive adhesives have become a major trend in this field. Acrylate?based pressure?sensitive adhesive is the most widely used pressure?sensitive adhesive at present. Its performance has been improved after modification. Nevertheless, the modification process has some disadvantages, such as environmental pollution and low resource utilization. Since rubber has the advantages of low cost, superb mechanical properties, high and low temperature resistance, and environmental friendliness,and so on.Rubber?modified acrylate?based pressure?sensitive adhesives have become a development trend in this field. This paper summarized the development process of rubber?modified acrylate?based pressure?sensitive adhesives and outlined and compared the types of rubber and the advantages and disadvantages of modified products.

This paper systematically studied the material compatibility, storage stability, and miscibility with diesel fuel of polyoxymethylene dimethyl ethers (PODE _n ) from the point of view of its application performance. The results show that the PODE _n is generally highly compatible with common metal materials, such as copper, brass, steel, cast iron, cast aluminum, and solder. In comparison, blended diesel fuel with PODE _n at a volume fraction of 10% is highly compatible with polyester polyurethane rubber and fluororubber but poorly compatible with nitrile rubber and polyether polyurethane rubber. In the storage stability test conducted at 43 °C for 16 weeks, PODE _n demonstrates satisfactory storage stability. Excellent miscibility stability occurs after the blending of automobile diesel fuel with PODE _n at a volume fraction of 10%. In general, as a component of blended diesel fuel, PODE _n delivers satisfactory application performance.

This paper used a rubber processing analyzer (RPA) to study the effect of different amounts of epoxidized soybean oil and antioxidants on the rheological properties of brominated butyl rubber (BIIR) during the thermal oxidative aging process and discussed the cause of degradation and gel generation of BIIR.The results show that the rheological properties change trend is consistent with the GPC data,which proves that the thermal oxidative aging of BIIR is a process involving both molecular cross?linking and degradation;epoxidized soybean oil and antioxidants can greatly slow down the rate of the gel generation and molecular chain degradation during the aging process of BIIR.Different antioxidants have different anti?aging effects on BIIR.Antioxidant 1076 has a stronger inhibitory effect on oxidative degradation of BIIR than antioxidant 264.

Taking the Bohai Q oilfield as an example, this paper focused on how to improve the effect of liquid production increase in fluvial facies reservoir and counted the effects of measures to increase the production of oil wells in the oilfield in the past five years. The sensitivity of oil wells was analyzed from static and dynamic aspects,and the effects of liquid production increase measures on static and dynamic parameters were studied to analyze the effective timing and scale of increasing liquid production.According to the effect of the measures, classification schemes for the liquid production increase of water?drive reservoir in Bohai fluvial facies were established.The results show that if oil wells in the reservoir are in Class Ⅰ liquid production increase stage (20 000 mD ? m<formation coefficient ≤40 000 mD ? m,0<flow coefficient≤300 mD ? m/(mPa ? s）,25 000 m³<accumulated oil production before liquid production increase≤50 000 m³,0<accumulated liquid production before liquid production increase≤300 000 m³,65%≤water content before liquid production increase<80%),their daily oil production increment after liquid production increase will be possibly greater than 30.0 m³. The daily oil production increment of oil wells in Class Ⅱ liquid production increase stage is between 15.0 m³ and 30.0 m³,and that of oil wells in Class Ⅲ liquid production increase stage is less than 15.0 m³.The high?efficiency stimulation timetable was verified in the southern part of the Bohai Q oilfield.This is of great application value and can provide a basis for the efficient development of offshore fluvial water?drive reservoirs.

The properties of alumina supports are the key factors affecting the propane dehydrogenation performance of Pt?Sn/γ?Al₂O₃ catalysts.In this paper,γ?Al₂O₃ supports were prepared at three calcination temperatures of 450,650,850 ℃,and the structures and properties of the supports and supported catalysts were systematically studied by XRD,XRF,NH₃?TPD,Py?FTIR, CO?FTIR,OH?FTIR,and other characterization methods.The properties of the propane dehydrogenation reaction were evaluated by a fixed?bed micro?reaction evaluation device with online analysis,and the gas?phase product distribution and coking properties were analyzed.The results show that with the increase in calcination temperature,the surface acid content of γ?Al₂O₃ supports decreases,and calcination at 850 ℃ almost eliminates the weak L acid centers on the surface.This indicates that the number of coordinated unsaturated Al sites on the surface of γ?Al₂O₃ and surface hydroxyl groups decreases as the calcination temperature grows,which is not conducive to the high dispersion of metal active centers.Both CO?FTIR and TEM results confirm the formation of larger Pt clusters on Pt?Sn/γ?Al₂O₃?850,and more Pt active phase structure with saturated coordination can promote the occurrence of side reactions such as deep dehydrogenation and reduce the selectivity of propylene products.

Organic sulfides widely exist in natural resources such as petroleum and coal,which have abundant resource reserves.In the petroleum refining industry,the cleavage of C-S bonds is usually required for the desulfurization of petroleum fractions. Among them,the transition metal?catalyzed cleavage reactions of C-S bonds have attracted the attention of researchers owing to the advantages of high efficiency,mild conditions,and low pollution.This review summarizes the progress in transition metal?catalyzed C-S bond cleavage reactions of different types of organic sulfides,and provides insights into Pd,Cu,Ni and Fe catalytic systems and mechanisms.Moreover,the development of such reactions is proposed.

Rare earth complexes of Eu³⁺ and Nd³⁺ with pyridine dicarboxylate [Ln(2,6?dipic)(2,6?Hdipic)(H₂O)₂]?4H₂O (Ln: Eu, Nd) were synthesized by hydrothermal method. The structure, magnetism and thermodynamic properties of the complexes were studied by the means of single crystal X?ray diffraction measurement, magnetic test, thermogravimetric analysis and differential scanning calorimetry analysis. The results show that two complexes are isostructural crystallizing in the monoclinic system of space group P2₁/c. There are two different coordination modes for pyridine?2,6?dicarboxylic acid in the crystals. The complexes exhibit antiferromagnetism with obvious orbital coupling effect. The prepared complexes have good thermal stability.

Tin phosphide (Sn₄P₃) as the anode material for lithium?ion batteries exhibits high theoretical specific capacity (1.255×10³ mA ? h/g). However, the huge volume expansion and particle agglomeration during the charging and discharging processes lead to serious capacity attenuation. The carbon?coated Sn₄P₃?graphene composite (Sn₄P_3?G@C) was successfully prepared by using graphene as the framework and amorphous carbon material as the coating layer. Sn₄P₃?G@C composite shows a high discharge specific capacity of 0.521×10^-3 mA ? h/g after 70 cycles at 0.05 A/g, and the discharge specific capacity of 0.433×10^-3 mA ? h/g can be maintained after 150 cycles at 0.10 A/g. After 300 cycles at 0.50 A/g, the reversible specific capacity of 0.330×10^-3 mA ? h/g can be exhibited. The co?existence of sheet graphene and carbon coating can not only stabilize the structure of Sn₄P₃ and improve the electrical conductivity of the material, but also effectively alleviate the problem of volume expansion and prevent the agglomeration between particles. Sn₄P₃?G@C shows good lithium storage performance.

This paper in situ introduced a mixture of phytic acid,methanol,water,chromium nitrate nonahydrate,N,N?dimethylformamide in polyvinyl alcohol casting solution, where phytic acid and chromium nitrate nonahydrate formed a metal organic framework (MOF) with a three?dimensional structure. Glutaraldehyde was the crosslinking agent to crosslink polyvinyl alcohol into a network structure, and a series of anion exchange membranes with a porous MOF were constructed for fuel cells（MOF@PVA）. During the experiment, the structure and properties of the membranes were optimized by adjusting the Cr³⁺ content. Characterization and performance test results show that the obtained composite membranes are flat and uniform in morphology, with a large number of pore structures available for OH^- migration and retention of water molecules. Additionally, membrane conductivity, water content, and mechanical properties increase with the rising Cr³⁺ mass fractions. When m(Cr³⁺)/m(conductive film) is 0.012, the conductivity is the highest, that is 24.9 mS/cm. The membrane conductivity is only reduced by 8% after being immersed in a 3 mol/L NaOH solution at 80 ℃ for 168 hours.

The precursor NiMoO₄ nanorod arrays were prepared on nickel foam by a hydrothermal method using ammonium molydate tetrahydrate [(NH₄)₆Mo₇O₂₄·4H₂O] as the Mo source and nickel nitrate hexahydrate [Ni(NO₃)₂·6H₂O] as the Ni source, and subsequently were nitrogenized via a thermal treatment to obtain the NiMoN with rod?like array structure.The phase structure and surface morphology of the catalytic electrode material were characterized by X?ray diffraction (XRD) and scanning electron microscopy (SEM).Besides,the half?reaction oxygen evolution reaction (OER),hydrogen evolution reaction (HER),and overall water electrolysis performance of the material were evaluated by adopting various electrochemical characterizations,including linear scanning voltammetry (LSV),Tafel slope, and electrochemical impedance spectroscopy (EIS).The test results show that the NiMoN?9 catalytic electrode material has both high OER and HER activities.The OER overpotentials for this material to reach 100.00 mA/cm² are only 293 mV and 340 mV respectively in alkaline fresh water and alkaline simulated seawater,while the corresponding HER overpotentials are 361 mV and 400 mV.In addition,the NiMoN?9 material also exhibits good activities in both water electrolysis and seawater electrolysis with the cell voltages of 2.016 V and 2.032 V respectively to obtain 100.00 mA/cm² as well as robust stabilities over 55 h.

Hydrocracking is a crucial technology in the refining and petrochemical sectors. It is of great theoretical and practical significance to deeply understand the mechanism of hydrocracking reactions with the aid of reaction kinetics modeling. This paper recounted the research progress in the kinetic modeling of heavy oil distillation and hydrotreating and shows the methods for computing model parameters corresponding to the modeling method and predicting products. The study showed that the reaction kinetics modeling evolved from the decentralized lumped model based on the distillation range from a macroscopic perspective to a continuous lumped model based on production scenarios and then to a complicated microscopic lumped model at the molecular level. In addition, the study compared the advantages and disadvantages of various models in terms of their capacity to reliably predict the composition of products, the intricacy of parameter estimation, rate coefficients, feed dependence, and experimental data required. It also explained the industrial applicability of the lumped model as well as the construction and method for solving molecular hierarchical reaction networks in molecular lumps. Finally, it gives the development prospects of the lumped kinetic model according to the modeling difficulties, the computing power of computers, and the analysis of technology development trends.

This study uses the solvent extraction method to separate and recover aluminum and nickel from the alkali leaching residue of spent hydrogeneration catalysts. It compared and analyzed the extraction efficiency of P204 (Di (2?ethylhexyl) phosphate) and P507 (2?ethylhexylphosphonic acid mono?2?ethylhexyl ester) and investigated the effects of initial pH, the volume fraction of P204, the saponification rate of P204, and the ratio of V(org)/V(aq) on the extraction of aluminum and nickel in the P204 extraction system. The experimental results show that P204 demonstrates better extraction performance than P507 in the separation of aluminum and nickel. Under a concentration of 35% and saponification ratio of 30% of P204, initial pH of 2.75, and V(org)/V(aq) of 3∶1, the extraction rate of aluminum and nickel is 96.45% and 2.77%, respectively. In the two?stage countercurrent extraction process, the extraction rate of aluminum can reach more than 99.50% while that of nickel is below 3.60%. The loaded organic solvent was stripped at 60 ℃ and V(org)/V(aq) =2∶1 for 20 minutes by 6 mol/L HCl solution, and the stripping efficiency of aluminum in the organic phase is 98.04%. Thus, the separation of aluminum and nickel in spent catalysts can be effectively realized.

The effect of hydraulic retention time (HRT) on the performance of a combined packed sequencing batch biofilm reactor (SBBR) for treating simulated domestic wastewater was investigated.The changes of denitrification performance,denitrification rate and EPS in SBBR were detected and analyzed at different HRT (16 h, 12 h and 8 h).The results indicate that HRT has no significant effect on COD removal rate.Shortening HRT inhibited the activity of microorganisms on the biofilm,increased the mass fraction of TB?EPS and LB?EPS by 30.25% and 29.88%,and decreased the denitrification rate to 64.1%.The best HRT obtained from the experiment was 12 h.

Class II?B reservoirs have become the main exploitation target in Daqing Oilfield, and their geological reserves account for 45.8% of the Class II reservoirs.In view of the huge difference in the exploitation of Class II?B reservoirs,a two?phase mathematical model of viscoelastic polymer solution and crude oil was built,and the logarithmic conformation method was used to transform the model.The VOF method was employed to track the two?phase interface in the displacement process,and thus a two?phase numerical model of viscoelastic polymer solution and crude oil was obtained.Moreover,the effects of pore structure and viscoelasticity of polymer on microscopic oil displacement efficiency were studied by the microscopic model of Class II reservoirs. The results demonstrate that higher reservoir heterogeneity is accompanied by lower microscopic oil displacement efficiency,and the oil displacement efficiency of Class II?A reservoirs with better pore parameters is 2.10% higher than that of Class II?B reservoirs.With the increase in viscosity,the microscopic oil displacement efficiency increases,and the oil displacement efficiency of schemes with a viscosity ratio of (viscosity ratio of polymer to crude oil) 1.5 : 1,2.0 : 1 and 10.0 : 1 is 0.59%,0.80% and 4.10% higher,respectively, than that with a viscosity ratio of 1.0 : 1. With the increase in elasticity, the microscopic oil displacement efficiency rises, but when the elasticity is higher than 13 s,the microscopic oil displacement efficiency decreases slightly,which indicates that the elasticity of polymer solution has an optimal value for improving oil displacement efficiency.The research results provide important theoretical support for the polymer flooding development of Class II?B reservoirs in Daqing oilfield.

Plasma modification is an effective way to improve the catalytic activities of materials.Firstly,Co₂(OH)₂CO₃ precursor was synthesized by a hydrothermal method.Then,the precursor was subjected to the oxygen atmosphere low?temperature plasma, and the surface modified Co₃O₄ catalyst (Co₃O₄?P) was obtained,which was further characterized the XRD,SEM,H₂?TPR,O₂?TPD,TEM,XPS,FTIR,Raman spectrum and UV?visible spectrum.The results demonstrate that plasma treatment could reduce the average valence state of Co elements in Co₃O₄ to form more defective sites on the catalyst surface,and lower the Co-O bond energy of Co₃O₄ to improve its low temperature reduction performance.Under the irradiation of full solar spectrum light with intensity of 776 mW/cm²,reaction space velocity of 30 000 mL/（g·h）and toluene concentration of 500 μg/g，the toluene degradation performance of the Co₃O₄?P catalyst could reach 100.0%，which was approximately twice that of the Co₃O₄ catalyst (Co₃O₄?T) prepared by thermal calcination.

Hydroisomerization reactions are widely adopted in octane upgrading,diesel fuel coagulation reduction and lubricant base oil dewaxing and viscosity reduction.One?dimensional pore zeolites have unique pore?selective effects on straight?chain alkanes,and thus server as the most suitable acidic carrier and active component for isomerization in hydroisomerization reactions. Its isomerization performance is mainly depended on the topologic structure,acid properties and crystal size of zeolite.This paper mainly summarizes the research progress of synthesis,modification and application of one?dimensional pore zeolites with different topologies in recent years as well as the development trend and application prospect of these zeolites for hydroisomerization.

CeO₂?X (X is the hydrothermal synthesis time, X=3, 6, 12, 24 h) carriers were prepared by varying the hydrothermal synthesis time using Ce(NO₃)₃·6H₂O and urea as raw materials, and CuO/CeO₂?X catalysts were obtained by isovolumetric impregnation with active component Cu, which were applied to methanol steam reforming (MSR) reaction. The effects of hydrothermal synthesis time on the structure and physicochemical properties of the prepared CeO₂?X carriers and CuO/CeO₂?X catalysts were explored by XRD, BET, H₂?TPR.The performances of the CuO/CeO₂?X catalyst samples were evaluated in methanol steam reforming(MSR) reaction.The results show that the CuO/CeO₂?6 has good catalytic activity. At the reaction temperature of 280 °C, when the molar ratio of water to methanol was 1.2, and the space velocity of methanol vapor (GHSV) was 800 h^-1, the methanol conversion rate could reach 92.8%.

Morphology regulation is an important way to improve the performance of electrocatalytic hydrogen evolution reaction. This paper investigated the effect of NiCoP with different dimension on the hydrogen evolution reaction by combining theoretical calculation and experimental analysis methods and constructed structural models of 1D nanowires (NW?NiCoP) and 2D nanosheets (NS?NiCoP).Simulation results show that NW?NiCoP exhibits higher electronic density of electronic states near the Fermi level, which is beneficial to efficient charge transfer. NS?NiCoP features higher hydrogen adsorption energy, which is favorable for the Volmer reaction.NW?NiCoP,NS?NiCoP,and 3D nanosheet?wires (NSW?NiCoP) were prepared by hydrothermal and phosphating processes. Electrochemical tests on NiCoP with different dimension indicate that the overpotential is 45 mV for NSW?NiCoP at -10 mA/cm².

4?Isobutyloxy?2?cyclohepten?1?one was prepared by the condensation of isobutyryl chloride and 4?hydroxy?2?cyclohepten?1?one.The effects of various amounts of 4?dimethylaminopyridine(DMAP),reaction temperature and reaction time on the esterification reaction were investigated under the condition of no condensation agent.The results show that the optimized reaction condition is 0.3 mmol of DMAP under 25 ℃ for 3 h with a yield of 89%.The results of the NMR show that the synthesized product was the target molecule 4?isobutyloxy?2?cyclohepten?1?one.This esterification reaction features high yields under mild reaction conditions without the involvement of condensation agents,which is in line with the concept of the development of green chemistry.

Metal?nitrogen doped carbon is an emerging class of non?precious metal electrocatalysts used in carbon dioxide reduction reactions(CO₂RR).Metal?nitrogen doped carbon is an emerging class of non?precious metal electrocatalysts in carbon dioxide reduction reactions(CO₂RR).Current preparation methods mainly use impregnation?based post?processing,which often involves multiple preparation steps and limited types of metals.In this work,an iron?copper(FeCu) and nitrogen doped carbon catalyst was prepared through a coordination competition strategy.In the preparation,4,4?bipyridine served as ligand and iron nitrate and copper chloride as metal sites to form FeCu coordination polymers,which was directly transformed into FeCu?nitrogen doped porous carbon catalysts.The physicochemical properties such as morphological structure,metal species state and pore structure were characterized by SEM,TEM,XRD and N₂ adsorption?desorption,respectively.The performance of different FeCu?nitrogen doped carbon catalysts in electrocatalytic CO₂RR to syngas was examined in a three?electrode system.The regulation of n(CO)/n(H₂) in syngas was studied by adjusting the metal composition,metal combination and pyrolysis temperature,etc.The n(CO)/n(H₂) generated in the wide potential range of -0.7 V to -1.3 V can be regulated in the range of 0.15~3.33,which can meet the supply gas ratios for important reactions such as methanol synthesis,Fischer?Tropsch reaction and syngas fermentation.

In order to investigate the synergistic catalytic aquathermolysis after external catalyst entering the reservoir and complexation with in?situ inorganic minerals,a simulated internal and external synergistic catalyst of montmorillonite?supported zinc citrate complex was prepared,and its catalytic viscosity reduction performance for heavy oil was investigated.The heavy oil before and after the reaction was analyzed by thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),gas chromatography(GC) and elemental analysis(EA).The results showed that the composite catalyst B@Zn(Ⅱ)L increased the viscosity reduction rate of heavy oil from 55.2% to 65.4% at 30 ℃,which confirmed the phenomenon of internal and external source synergistic catalysis in heavy oil thermal recovery.After synergizing the composite catalyst B@Zn(Ⅱ)L with the hydrogen supply agent ethanol,the viscosity reduction rate of heavy oil increased from 65.4% to 80.1%.After the reaction of heavy oil, some of the high hydrocarbon compounds in the heavy oil were cracked into low hydrocarbon compounds after the reaction,and some heavy components were decomposed into light components.Therefore, the wax precipitation point of heavy oil decreased,the mass fraction of N and S decreased,the content of high hydrocarbons decreased,and the content of low carbon hydrocarbons increased.

This paper studies the stability of crude oil emulsion characterized by conductivity difference between upper and lower layers. According to the changes of conductivity in the upper and lower layers of crude oil emulsion system, combined with optical microscope observation, the methods and conditions to characterize the stability of crude oil emulsion can be studied by the difference of conductivity between the upper and lower layers. Research finds that when the crude oil system is demulsified and phase separated, the composition, morphology and conductivity of the upper and lower emulsions will be different.Therefore, the conductivity difference between the upper and lower emulsions can be used as the characterization parameter of emulsion stability. By measuring the conductivity and the difference values of the upper and lower layers of the system at different electrical test signal frequencies (0.1,1.0,10.0,100.0 kHz), it is found that the conductivity values and the difference values at high frequency are greater than those at low frequency, and the sensitivity is higher. In addition,when the conductivity difference is greater than 15%, the system is unstable. The experimental results show that the method is also suitable for emulsion system containing anionic surfactant.

During the injection process, micro?nano bubbles are generated in the oil?displacing agent polyacrylamide (HPAM) system. This will lead to the oxidative degradation of HPAM and the loss of viscosity. In order to determine the effect of micro?nano bubbles on the change rule of the viscosity retention rate and structure of HPAM solution, the viscosity retention rate at different aeration conditions was studied, and technologies such as dynamic laser scattering, biological microscopy, and infrared spectroscopy were carried out. Results showed that the viscosity retention rate of HPAM sample, which was prepared with simulated mineralized water after 20 mins circulation of the micro?nano bubbles generator with air as the gas source, decreases the most, and its viscosity average molecular weight is also the lowest. This is attributed to the chemical reaction between oxygen and HPAM molecules in the solution, leading to oxidative degradation. The micro?nano bubbles containing air increase the solubility of oxygen in the solution and generate hydroxyl radicals (·OH), thereby reducing the viscosity retention. In the absence of inflation, micro?nano bubbles are formed in the HPAM solution during the preparation process due to mechanical shear, but the high concentration of the solution hinders the dispersion of micro?nano bubbles, thereby slowing down the decrease in viscosity retention. In addition, micro?nano bubbles have a longer stabilization time in solution than large bubbles, and will affect the particle size distribution of the polymer, resulting in uneven particle size distribution and larger average particle size.

In the process of hydrogen storage by MOFs materials, the low thermal conductivity of the materials leads to heat accumulation,which affects the hydrogen storage performance.In order to improve the thermal conductivity of the adsorbent material and take into account its hydrogen storage capacity, numerical simulation was used to analyze the optimal regulation range of the thermal conductivity of the adsorbent material.The results show that when the thermal conductivity of the adsorbent material is in the range of 0~1.2 W/(m·K), the maximum temperature, average temperature and hydrogen absorption capacity of the hydrogen storage tank are obviously improved with the increase of thermal conductivity.When the thermal conductivity of the material is greater than 1.2 W/(m·K), the improvement effect is significantly weakened; when the material thermal conductivity is greater than 2.0 W/(m·K), the improvement effect almost disappears. Therefore, the optimal thermal conductivity of the adsorbent should be controlled at about 1.2 W/(m·K).

Natural gas hydrates have vast reserves and are considered a new clean energy source for replacing traditional fossil fuels such as coal and oil in the future.The formation, inhibition and decomposition of natural gas hydrate are affected by many factors.When studying the inhibition and acceleration effect of chemical agents on hydrate decomposition,multiple factors should be considered, such as fresh water or sea water, different gas?liquid ratios in the reactor, and pressure. In this paper, hydrate?related simulation experiments were carried out through a self?designed visualization simulation device for hydrate formation,inhibition and decomposition in wellbore. Under a gas?liquid ratio of (150 : 350),the combined effects of a laboratory?prepared KHI3 inhibitor and different concentrations of NaCl were analyzed to determine the optimal concentration combination. The experiment found that under the compound scheme of 3%NaCl+1%KHI3, hydrate is not easy to generate, but when the concentration of KHI3 is 2%, the nucleation rate of hydrate increases instead,which promotes the generation of hydrate.In practical applications,the concentration of the inhibitor should be strictly controlled to avoid pipeline blockage caused by massive hydrate formation.

Layered double hydroxides (LDHs) has simple synthesis process,flexible structure,economy,environmental protection and anion exchange,which strengthen its application range in the field of anti?corrosion coatings.The target properties of LDHs can be achieved by a combination of one or more processes,or chemically modified by surface modification and internal anion replacement,enhancing the applicability of LDHs to meet the needs of different fields of application.This paper mainly focuses on the synthesis method of LDHs,the mechanism of corrosion protection,the practical application of LDHs corrosion protection,and its limitations and prospects.It analyzes the advantages and disadvantages of various synthesis methods,and provides suggestions for future research on the application of LDHs in the field of corrosion protection.

To efficiently remove organics in coking wastewater, this paper prepared an amphiphilic chitosan?loaded bentonite adsorbent (C18CS?BT).The structure and morphology of the adsorbent were characterized by Fourier transform infrared spectroscopy (FT?IR),X?ray diffraction,and scanning electron microscope.By comparing the removal rates of C18CS?BT,unmodified chitosan?loaded bentonite (CS?BT),and bentonite (BT),the study explored the effect mechanism of hydrophobic modified adsorbent on the removal of the organics in coking wastewater.The results show that compared with BT and CS?BT,C18CS?BT features lower dosage, wider application range of pH value,and shorter adsorption equilibrium time.The optimized treatment process is the adsorbent dosage of 1.5 g/L,the adsorption time of 60 min,and the system pH value of 7.0. The COD in coking wastewater after BT, CS?BT and C18CS?BT treatment is reduced from 342 mg/L to 264,218,146 mg/L, and the corresponding removal rates of organics are 22.81%,36.26% and 57.31%, respectively. GC?MS result analysis also confirms that C18CS?BT could remove most of the organics in coking wastewater, especially long?chain alkanes and their derivatives.The hydrophobic modification of the adsorbent can effectively improve the removal performance of organics in coking wastewater.

The Tb coordination complex [Tb(H₂O)₈]?(L)?2(4,4'?bipy)?3H₂O（complex 1） was synthesized by hydrothermal reaction of sodium 1,3,6?naphthalene trisulfonate (Na₃L) and 4,4'?bipy (4,4'?bipy) with Tb(NO₃)₃?6H₂O. The molecular structure and composition of complex 1 were characterized by single crystal X?ray diffraction, FT?IR spectroscopy, thermogravimetric analysis and elemental analysis. Thermal stability and fluorescence emission properties of complex 1 were also evaluated. The results indicate that Tb³⁺ is eight?coordinated in a tetragonal antiprismatic coordination configuration and coordinates with eight H₂O molecules to form [Tb(H₂O)₈]³⁺.L^3- does not coordinate with metal ion, but only balances the positive charge in the molecule. The formation of hydrogen bonds between the sulfonic acid group of the L^3- and the coordinating H₂O molecule connects the [Tb(H₂O)₈]³⁺ and the L^3- to form a one?dimensional chain structure,which in turn expands into a two?dimensional lamellar structure.The fluorescence emission peaks of complex 1 at 395，453 nm are the characteristic peaks of Na₃L, and the emission peaks at 545,601，641 nm are the characteristic peaks of Tb³⁺.

The preparation of activated carbon from residue of a distillation reactor is an efficient and economical strategy for the utilization of hazardous waste resources.However,the prepared activated carbon is generally powdered,which is difficult to meet the requirements of industrial application.In this work,the activated carbon microspheres were prepared based on the rectification residue activated carbon from the powders,using deionized water as the solvent and polyacrylic acid (PAA),sodium alginate (SA) and Ca²⁺ as the additives.The effects of SA,Ca²⁺ and PAA amount on the structure and mechanical strength of the activated carbon microspheres were investigated.X?ray diffraction,Fourier transform infrared spectroscopy and Raman spectroscopy were used to investigate the shaping mechanism of activated carbon microspheres.The activated carbon microspheres were applied in the tetracycline adsorption,and the maximum adsorption capacity of tetracycline was up to 257.8 mg/g.At the same time,after 9 months of water stability test,the activated carbon microspheres still had good adsorption performance and mechanical strength. This shaping strategy adopted green and economical raw materials,which could effectively solve the problems of powder shaping and poor performance of microspheres,and provide the effective solution for the industrial application of high?performance materials.

To prevent accidents like the "3?12" explosion and fire incident in the hydrogenation unit of a petrochemical enterprise in Jiujiang, Jiangxi Province, this study proposes the application of Hazard and Operability Analysis (HAZOP) and Safety Integrity Level (SIL) classification in the basic design phase of the emergency cut?off function hazards control project for a refining and chemical enterprise. HAZOP analysis adopts a workflow based on the parameter preference method while SIL classification is based on the LOPA (Layers of Protection Analysis) method, following the ALARP (As Low As Reasonably Practical) principle. HAZOP & SIL classification was carried out for a coking steam kerosene hydrorefining unit, a hydrogenation combined diesel hydrorefining unit and an ethylbenzene unit in a refining enterprise. A total of 12 accident scenarios were identified and 6 recommended measures were put forward. The results demonstrate that HAZOP & SIL classification can effectively assist the refining and chemical enterprise in managing the risks of intermingling pressures, maintaining control over safety production, reducing intermingling pressure risks to an acceptable level, or eliminating them promptly, thereby preventing accidents caused by intermingling pressures and ensuring the inherent safety of the refining and chemical enterprise.

The large?scale use of fossil fuels has led to excessive CO₂ emissions, resulting in a series of problems such as rising temperatures, melting glaciers, and the accumulation of diseases and pests. Using electrochemical reduction of CO₂ (CO₂RR) to convert CO₂ into valuable chemicals and fuels has become a way to realize the carbon cycle. Over the years, good progress has been made in using metals and their oxides, carbon based materials, monatomic catalysts and other electrocatalysts for CO₂RR, but rare earth metals as "industrial vitamins" have been rarely reported for CO₂RR. This paper summarizes the application of rare earth elements as carriers, main catalysts and cocatalysts in CO₂RR, and explores the catalytic performance of rare earth materials in CO₂RR, so as to promote practical research of industrial application.

The traditional method for determining the oil content of oily sludge was improved, and the extraction smartphone image colorimetry was established by combining the image colorimetry with the pretreatment method of hot solvent extraction. The effects of RGB value, different color channels, shutter time, sensitivity, white balance and other parameters on the determination of oil content were investigated. Under the premise that the light source was tungsten iodide lamp and the front camera of Samsung A8s mobile phone was used, the best test conditions were finally determined: white balance value was 2 800 K, sensitivity value was 100, shutter time was 1 / 2 000 s. The linear correlation coefficients of the method under the optimal test conditions were more than 0.99 under the optimal test conditions, and the linear range was similar to that of the spectrophotometric method, with the detection limit of 0.06% and the lower limit of 0.24%. The recoveries of 8 groups of parallel standard samples were 96%~103%, and the relative standard deviation was 2.26%, which indicated that the accuracy of this method was relatively high. Compared with the traditional method, this method is more simple and rapid, and its accuracy can meet the needs of conventional oil content measurement, which is expected to realise the rapid on?site determination of oil content of large?scale oil?containing sludge in plants.

Using artificial simulation of diesel contaminated soil, the degradation and remediation ability of functional microbial communities on diesel contaminated soil, as well as changes in microbial diversity and microbial structure composition, were studied. The experimental results of microbial community degradation of diesel in soil showed that after 30 days of degradation, the final degradation rate of microbial community on diesel pollution in soil reached 74.3%.The respiratory intensity of the microbial community in the soil gradually increases within 30 days. When the soil depth changes, the degradation ability of the microbial community gradually weakens with the increase of depth. The results of high throughput sequencing showed that after 30 days of degradation, the microbial diversity and richness in the soil increased compared with the initial degradation, indicating that the microbial community could adapt to the diesel pollution environment well. The initial microbial community for diesel degradation is mainly composed of Proteobacteria, Firmicutes, and a small amount of Bctoidetes. After 30 days of cultivation, the main dominant bacteria in the surface soil are Proteobacteria, while the main dominant bacteria in the deep soil are Firmicutes. Studying the remediation of diesel?contaminated soil by microbial communities and changes in microbial structure and diversity, technical support can be provided for the remediation of diesel?contaminated soil.

While fossil energy is being exhausted day by day,and the problem of environmental pollution needs to be solved urgently.However,the social demand for energy is growing,so the development of green energy has received extensive attention from many scientific researchers.As an efficient energy conversion device,fuel cell has many advantages such as high efficiency, high performance and environmental friendliness.In the choice of fuel cell catalyst,Pt?based catalysts are the preferred materials because of their unique catalytic properties,but their high preparation cost and unstable catalytic properties have hindered the commercialisation of Pt?based catalysts.The working principle of Pt?based catalysts for cathode oxygen reduction reaction of proton exchange membrane fuel cells and the influencing mechanism of catalyst activity are briefly introduced.The research direction of Pt?based catalysts is summarized.Finally,the development direction of future research is prospected.

Pt0.5?Snx/γ?Al₂O₃ catalysts with different Sn loads were prepared by constant volume sequential impregnation method and ultrasonic shock method to improve metal dispersion. The catalysts were characterized by XRD, BET, H₂?TPR, CO?IR and TG, and the effects of Sn content on the active center structure and propane dehydrogenation performance of Pt0.5?Snx/γ?Al₂O₃ catalysts were investigated. The results showed that adjusting the n（Pt）/n（Sn） by changing the Sn content in the samples would lead to the difference in the spatial distribution of Pt and Sn species, and thus affect the mode of action between Pt and Sn. With the increase of Sn, the interaction between Pt?Sn helps to increase the dispersion of Pt, the number of active sites, the improvement of the reaction activity of the catalyst. However, when excessive Sn is introduced, a Pt?Sn alloy is formed, resulting in the coating of Pt, resulting in a decrease in the number of active sites and a decline in the reactivity.

A new method for the synthesis of esters by C=C bond breaking in olefins has been realised using cobalt nanoparticles (Co?NC?900) as catalysts and oxygen as oxidant.The catalytic system has a wide range of substrate applications and functional group compatibility.A diverse set of mono? and multi?substituted aromatic and aliphatic alkenes could be effectively cleaved and converted into the corresponding esters by C=C bond cleavage. In addition, the catalyst can be recycled up to six times without significant loss of activity.Characterization analysis revealed nanostructured nitrogen?doped graphene?layer coated cobalt nanoparticleis possibly responsible for excellent catalytic activity.Mechanistic studies revealed that alcohols or ketones derived from olefins under oxidative conditions are formed as intermediates,which subsequently are converted to esters through a tandem sequential process.

Under the hydrothermal synthesis,an organic?inorganic hybrid compound was prepared through the self?assembly process by using phosphomolybdic acid as a polyoxometallate (polyacid for short) building block and triphenylphosphine as an organic ligand.Its molecular formula was determined by X?ray single?crystal diffraction technique as H₁₅{(PMo₁₂O₄₀)₂[MoO₄?(PPh₃)₄]₂?[NaO₃?(PPh₃)₃][(H₂O?PPh₃)₃]（compound 1),which is a novel inorganic?organic hybrid material formed by electrostatic interactions between [PMo₁₂O₄₀]^3-,[MoO₄?(PPh₃)₄]^2-,[NaO₃?(PPh₃)₃]^5- and H₂O?PPh₃ building blocks.The IR spectrum,luminescence spectra and cyclic voltammetric characteristic curves of compound 1 were also tested,focusing on the photocatalytic degradation of methylene blue(MB).The good ability of compound 1 to degrade organic dyes was demonstrated by photodegradation analysis experiments.

Chiral epichlorohydrin is obtained by kinetic resolution of racemic epichlorohydrin through hydrolysis. Chiral epichlorohydrin is a valuable intermediate which is widely used in the synthesis of medicine and material. Salen refers to a base formed by the condensation of two identical aldehyde molecules and a diamine molecule, and the complex formed by its combination with metals is called Salen metal complex, which is often used in the synthesis of chiral epichlorohydrin. In this paper, the development of Salen metal complex catalysts and their application in chiral epichlorohydrin synthesis are reviewed. At the same time, the deactivation mechanism of catalyst in the process of hydrolytic kinetic resolution was investigated and the application prospect of synthesis of chiral epichlorohydrin using Salen metal complex catalysts was prospected.

Highstrength polymer materials with excellent mechanical properties and wear?resistance have been widely used in water pumps, electric generator and other fields as a new generation of bearing materials. A high performance polyurethane/carbon fiber composite （PUE/CF） was prepared by combining chopped carbon fiber (CF) with polyurethane elastomer (PUE), and the effects of carbon fiber content on the mechanical and tribological properties of the composites were investigated. The results show that the hardness of the composite can reach 60 ~ 68 HD, the tensile strength and elongation at break can reach 54 MPa and 298% respectively. Under dry friction condition, 0.16 of friction coefficient and 0.570% of wear rate can be obtained. Under water friction condition, 0.02 of friction coefficient and 0.129% of wear rate can be obtained. In summary, the composite prepared in this paper can meet the application requirements of polymer bearing bush and have broad application prospects in the field of automobile and ship.

The Ruddlesden?Popper (RP) perovskitetype composite cathode material was prepared by a sol?gel method,and the performance of using it as a SOFC cathode was evaluated.XRD result shows that the composite material calcined at 1 200 ℃ was (La_2/3Sr_4/3)FeO₄?(La_4/3Sr_8/3)Fe₃O₁₀ (LSF).At 400 ℃,the highest conductivity of the sample is 57.0 S/cm in air.At 800 ℃,the interfacial polarization resistance of the LSF electrode on La_0.9Sr_0.1Ga_0.8Mg_0.2O_3-δ (LSGM) electrolyte is 0.198 Ω·cm².Based on a single cell supported by a 300?μm?thick LSGM,the peak power density of the sample when used as a cell cathode was up to 670 mW/cm² when used as the cathode of the cell, with no performance degradation for 50 h of continuous operation.Experiments show that the LSF cathode has excellent and stable electrochemical performance,and is a very promising cathode material for SOFC.

After the application of a non?ionic polyether clear water agent in an oilfield in the Bohai Sea,the difficulty of dewatering crude oil in the downstream terminal treatment plant increased,and the water content of the outgoing crude oil frequently exceeded the standard.The Effect of nonionic polyether water clarifier on crude oil dehydration was researched,the reasons of difficulty in dewatering were analysed,and the emulsion could not be treated by conventional polyether demulsifier.Polyamines were synthesised from dimethylamine,dodecyl dimethyl tertiary amine and epichlorohydrin,while polyethylene?polyamines were used as cross?linking agents to synthesise polyamine copolymer emulsion breakers.The emulsion breaker can reduce the water content of the external crude oil to less than 0.5% at a concentration of 80 mg/L,and reduce the static dewatering time of the crude oil from more than 120 h to less than 48 h.This effectively solves the problem of excessive water content in the external crude oil of the terminal treatment plant.

The development of clean and renewable energy technologies is seen as the key to addressing energy and environmental issues.Oxygen evolution reaction (OER) plays key roles in storage intermittent energy,such as solar and wind,from water splitting.Recently, OER under neutral conditions receives considerable interests due to its environmental friendliness.However,the efficiency of OER under neutral environment is far below that under alkaline or acidic condition.In this review,the current researchers' understanding of the mechanism of OER under mild pH conditions is firstly outlined.Thereafter,several important characterisation techniques for in situ tracking of the electrocatalytic process of OER are presented,which is crucial to reveal the OER mechanism under neutral conditions.Moreover,an overview over catalytic materials towards neutral OER,including Co?,Ni?,and Mn?based catalysts,is provided.Finally,a brief outlook on the remaining challenges and possible strategies for promoting neutral OER is given.

With the rise of electric revolution and the establishment of "carbon dioxide emission and carbon neutrality" strategy, petroleum coke has got great development in value?added applications such as lithium cathode materials and high?grade prebaked anode.However,high value?added applications of petroleum coke all have strict requirements for sulfur content of petroleum coke. The high sulfur content in petroleum coke will have a negative impact on the high value application of petroleum coke.The research status of main desulphurization technologies of petroleum coke,including solvent extraction desulfurization technology,high temperature calcination desulfurization technology,oxidation desulfurization technology, alkali metal compound desulfurization technology,hydrodesulfurization technology,microbial desulfurization technology and process intensification auxiliary desulfurization technology are summarized.It was found that the desulphurisation rate of process?enhanced assisted desulphurisation could reach 93.6%,which could reduce the sulphur mass fraction in petroleum coke from 7.57% to 0.48%. The desulfurization technology of petroleum coke should maintain the principle that the structure of petroleum coke after desulfurization is not destroyed to the greatest extent.Therefore,oxidative desulfurization coupled process enhancement assisted desulfurization should have bright prospect in industrial application of petroleum coke desulphurization.

Paraffin is mainly composed of n?alkanes, small amounts of i?alkanes, cycloalkanes, aromatic hydrocarbons and trace amounts of S,N,O compounds. Under the action of ultraviolet light and heat, those compounds containing elements S,N,O,aromatic and unstable elements of alkene aromatic can be oxidated,resulting in a darker color and lower paraffin light stability.In order to explore the reasons for the deterioration of the paraffin light stability,the effects of internal factors such as nitrates,sulfides and oil content on the paraffin light stability were investigated.Orthogonal experiments were carried out to investigate the effects of ultraviolet absorbers,hindered amine light stabilizers,antioxidants and its compounding agent on the improvement of the paraffin light stability.The results showed that the best paraffin light stability was achieved when the additive amounts of UV absorbers, hindered amine light stabilizers and antioxidants in the compound were 300 μg/g, 300 μg/g and 300 μg/g, respectively.