The precursor was prepared by sol?gel method using ammonium molydate tetrahydrate [(NH₄)₆Mo₇O₂₄·4H₂O] as molybdenum source,nickle nitrate hexahydrate [Ni(NO₃)₂·6H₂O] as nickel source and H₃PO₄ as phosphorus source.NiMoP/C composites were then prepared by a following CVD (chemical vapor deposition) method.The physical and chemical properties of NiMoP/C composites were characterized by XRD,SEM,TEM,XPS,Raman,N₂?adsorption desorption and other test techniques. Meanwhile,the electrocatalytic hydrogen evolution performance of the NiMoP/C composite material was measured by CV,LSV, EIS,etc.The results show that the NiMoP/C composite material has high electrocatalytic hydrogen evolution performance with overpotential of -158 mV at the current density of -10 mA/cm² and Tafel slope of 111 mV/dec. So the NiMoP/C material is an excellent anode material suitable for electrolyzing water in acidic media due to its simply electrode preparation process preparation method.

In order to understand the temperature characteristic of complex modulus,the correlation between the double logarithms of complex modulus and expressions at different temperatures was studied through ten original asphalts produced by two kinds of crude oil as well as these asphalts after RTFOT and PAV.For the first time,through correlation between the slope and intercept of linear fitting correlation,the optimized mathematics formulas between complex modulus and temperature were determined. Mathematics models for different aging stages were established. Mathematics models are simple,accurate,and practical and show universal applicability by comparing measured data at single temperature with predicted data of three asphalts produced by the third crude oil.The data predicted by mathematics model meet the requirements of reproducibility precision of the test method of complex modulus.

Tahe asphaltene (T_A) was separated into heavy component(T_A1) and light component (T_A2). The surface morphology, crystal structure and functional group structure of T_A, T_A1 and T_A2 were characterized by Scanning Electron Microscope (SEM), X?ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT?IR) and ¹H?Nuclear Magnetic Resonance Spectrum (¹H?NMR). The results show that TA has less long?chain structure, more branched chains in side chains, and is mainly composed of short branched alkyl structure such as methyl, ethyl and propyl. Sub?components T_A1 and T_A2 show obviously different microstructure after separated from T_A. TA1 has the highest degree of graphitization, the longest branched chain, more side?chains of aromatic ring, less branched chains of alkyl side?chains and relatively strong aromaticity, while T_A2 has lower degree of graphitization, more branched chains of alkyl side?chains, less side?chains of aromatic ring and relatively weak aromaticity.

WO _x /SBA?15 catalysts with different loading amounts were prepared by wet impregnation method, and the effect of WO _x dispersion on the olefin disproportionation reaction was discussed.The results show that the loading amount affects the dispersion of WO _x on the carrier surface, as well as the catalytic activity.The best catalytic performance of WO _x /SBA?15 can be achieved with 10% loading amount of WO _x .The higher loading amount of WO _x could induce aggregation of WO _x on the SBA?15 surface, and then covering the active sites.The weaving properties of the samples were characterized by physical adsorption,XRD,SEM,and the acidity and acid amount of the samples were characterized by pyridine IR and chemisorption. Reaction evaluation shows that the sample with 10% loading amount of WO _x exhibits the best catalytic activity.The propylene yield of the 10% WO _x /SBA?15 catalyst is up to 50% and the propylene selectivity is nearly 90%.

SiO₂?CeO₂ carriers were prepared by hydrothermal synthesis method,and CuO?SiO₂?CeO₂ catalysts were synthesized by impregnation method with active component CuO.The carriers and catalysts were characterized by XRD,BET and H₂?TPR methods.The effects of the addition amount of SiO₂ for the specific surface area of the catalyst and the catalytic performance of the catalysts in methanol steam reforming for hydrogen production were also investigated.The obtained results indicated that appropriate addition of SiO₂ can increase the specific surface area of the support and catalyst,reduce reduction temperature of the active component CuO,and increase the conversion rate of CH₃OH.When the amount of SiO₂ is 2.5%,the specific surface area of CuO5.0%?SiO₂2.5%?CeO₂ is 112.8 m²/g,and the conversion rate of CH₃OH is 75.1%.Both of the specific surface of the catalyst and the conversion rate of CH₃OH will decrease with the content of SiO₂ continue to improving in the catalyst.

Using Ni and Mo as active components and Al₂O₃?USY as support material, the effect of citric acid on the catalytic activity of NiMoP was investigated. The results indicate that the total acid content on the surface of catalyst increases at first and reaches its maximum in the condition of n_L/n_Ni=1.0, then decreases as the increasing concentration of citric acid. Meanwhile, the stacking layer number of active phase MoS₂ and the average lamellar length are gradually increased. When the mole ratio of citric acid to Ni is 1.0(n_L/n_Ni=1.0), the catalyst shows the best activity. And the HDS and HDN rate at 340 ℃ reach to 99.6% and 99.7% respectively, which are better than the catalyst without modifying by citric acid.

With the rise of the textile industry, the treatment of printing and dyeing wastewater has grown up to be a hot spot in the industry. The key is how to efficiently separate organic dyes and inorganic salts. Due to its loose membrane structure, the loose nanofiltration membrane has a high dye rejection rate and good salt permeability, which has unique advantages in the treatment of printing and dyeing wastewater. Article focuses on the research progress in the preparation of loose nanofiltration membranes by phase inversion. The effect of nanomaterial modification the performance of the prepared loose nanofiltration membranes. The existing problems are analyzed, and the future research direction of using phase inversion method to make loose nanofiltration membrane is prospected.

Shape memory polymer (SMP) and self?healing polymer (SHP) as the representative of "smart" polymers have become the most dynamic research direction in this field,among which photosensitive SMP and SHP have been received wide attentions by industry and academia.This paper reviews the basic principles of photosensitive SMP and SHP, and classifies this type of polymers into reversible photochemical reaction SMP,photothermal SMP,photodimerization reaction SHP,photocrosslinking reaction SHP,and bifunctional SMP/SHP by referencing the most important and representative literature reports in recent years.

Cu?Cr modified activated carbon adsorbent was prepared by equal volume impregnation method.Using simulated coke oven gas as testing material,the effects of different transition metal active components and their loadings,different additives and loadings,calcination temperature on the removal activity of COS were investigated.The Cu?Cr modified adsorbent was characterized by X?Ray Diffraction (XRD), specific surface area (BET) and scanning electron microscope (SEM). The results show that the activated carbon modified simultaneously by Cu and Cr has the best adsorption performance of COS for coke oven gas, and the optimized preparation conditions of Cu?Cr modified activated carbon adsorbent are as follows: Cu and Cr loading is 5.0%, and 1.5% respectively, calcination temperature is 400 ℃. When the reaction temperature is 10 ℃, the breakthrough sulfur capacity of the modified activated carbon adsorbent is 1.47%, and the Cu?Cr modified activated carbon adsorbent shows good recycling performance. The characterization results indicate that CuO and Cr₂O₃ metal oxides are uniformly loaded on the activated carbon, and the specific area and pore volume of the adsorbent decrease after deactivation.

The UV shielding properties and photocatalytic properties of nanomaterials will vary due to the different surface binding energies of the materials themselves.Nano?zinc oxide (NPs?ZnO),nano?ceria (NPs?CeO₂), NPs?ZnO/CeO₂ and graphene oxide modified zinc oxide/ceria nanocomposites (NPs?ZnO/CeO₂@GO) were prepared,and the prepared samples were characterized by XRD,FT?IR,SEM,and the UV shielding properties and photocatalytic properties were tested. The results show that the UV shielding ability: NPs?ZnO<NPs?CeO₂<NPs?ZnO/CeO₂<NPs?ZnO/CeO₂@GO, the maximum degradation rate of methylene blue dye after 3 h treatment is:NPs?ZnO/CeO₂@GO(0.92)>NPs?ZnO(0.89)>NPs?ZnO/CeO₂(0.75))>NPs?CeO₂(0.66).Moreover,the photocatalytic activity of NPs?ZnO/CeO₂@GO is stronger than other photocatalysts participating in the experiments.

In view of the demand of sand and water control technology for high water?cut sand producing oil wells in Bohai oilfield,and the limitations of the current integrated technology of mechanical sand and water control, the technical route of integrating sand and water control with the application of flooding?sensitive gel is proposed.The feasibility of the integrated technology of selective water and sand control was demonstrated through testing the sand and water control performance of the flooding?sensitive gel. Based on the evaluation of the adaptability of the flooding?sensitive gel to the reservoir conditions and production conditions,the adaptability range of the flooding?sensitive gel for sand control and water control was clarified. Then the integrated technology of thickened gel for sand and water control was finally formed.The results show that the reservoir permeability damage and sand production rate can be controlled within 13% and 0.03%,respectively.The reservoir and water layer can be selectively blocked. The adaptability evaluation results showed that the temperature resistance of the flooding?sensitive gel was higher than 80 ℃, the salinity was 45 000 mg/L,and the maximum extraction strength was 257.6 m³/（d ? m）.With the application of the integrated technology of sand and water control in Z oilfield of Bohai Sea, the sand control period reaches 13~16 months with continuous effectiveness, the water cut is reduced by 3%~5% compared with previous testing results. The daily oil production is increased by 88.48% on average,and the extraction range reaches more than 50%.The integrated technology of flooding?sensitive gel sand and water control provides an idea for oil increase in high water cut sand production wells in offshore oil fields.

Formation damage control of Hutubi underground gas storage (UGS) presents a serious challenge due to low formation pressure coefficient and reservoir deep invasion of wellbore working fluid under large pressure difference during drilling and completion. Mineral composition analysis, expansion capacity, wettability and permeability reduction after spontaneous imbibition measurement of reservoir rocks were conducted to reveal formation damage mechanism of Hutubi UGS. That is the clay minerals hydrated swell and dispersion of water?sensitive formation and water?blocking effect of tight sand reservoir. Drilling fluid technical countermeasure of improving inhibition, weakening liquid wettability and enhancing temporary plugging was put forward. Amine inhibitor and surfactant ABSN were selected to optimize the current used drilling fluid. Temporary plugging particle size fraction distribution was determined based on the “optimal filling” bridging plugging theory. Laboratory and field evaluation show that the optimized drilling fluid is suitable for perforation and screen pipe completion with a permeability recovery more than 90% and effective inhibition of clay swell. The results provide reference for improving formation damage control effect of depleted gas reservoir drilling and completion.

Against the background of fossil fuel exhaustion and lithium resources shortage,sodium?ion batteries are considered promising secondary batteries due to their abundant resources,low theoretical cost, good quick?charge performance and excellent low?temperature performance.They are expected to play a key role in developing new energy,large?scale energy storage and low?speed electric vehicles.The selected cathode material is one of the important factors influencing the energy density,cycling performance and rate performance of a sodium?ion battery.This paper reviews the cathode materials of sodium?ion batteries,including transition metal oxides, polyanionic compounds,Prussian blue compounds and organic compounds.The paper introduced the advantages and disadvantages of sodium?ion batteries,analyzed the characteristics and research focuses of various cathode materials,and provided an outlook on the development direction of cathode materials for sodium?ion batteries.

Taking oily sludge as the research object,this paper conducted solidification experiments with fly ash, clay, and laboratory?made liquid binder as a composite binder.It explored the effects of dosages (mass fractions) of binder components on the solidified block strength and determined the optimum dosage of the curing agent. The results show that the strength of the solidified block is the best in the case of the fly ash dosage of 30%,the clay dosage of 10% and the liquid binder dosage of 5%. Under the optimal process conditions, the cold strength of the solidified block is 2.19 MPa and the hot strength is 2.21 MPa, which indicates that it has sufficient cold strength and thermal stability. The forming mechanism of the solidified block was studied with the help of Fourier transform infrared spectroscopy (FT?IR),X?ray diffraction (XRD), and scanning electron microscopy (SEM). The forming mechanism of the solidified block was put forward according to the characterization results.

During gravel packing operations in offshore oilfields, incomplete packing or packing failure may occur due to design, irregular borehole, formation, and other reasons, which has a great impact on the production of oil wells. A new type of multi?channel bypass screen is designed and developed. After conventional packing is completed, the gap section continues to be packed through the bypass channel. The performance of the designed multi?channel bypass screen is evaluated with a self?developed large full?scale horizontal well gravel packing test simulation system, and the following conclusions were obtained through experiments. In the gravel packing experiment through the bypass pipe without a sand bridge, the packing efficiency of the bypass section measured is 100.0%. When the glass conveying pipe is connected, the ratio of the return flow rate at the outlet to that of the glass conveying pipe is 0.68 : 1. The liquid flow rate in the bypass channel is greatly improved compared to that in the unpacked clean water experiment.The packing efficiency of the gravel packing test through the bypass pipe with a sand bridge is 62.5% higher than that of the conventional screen. The ratio of the return flow rate at the outlet to that of the glass conveying pipe is 1.60 : 1.The experiments show that the new screen has favorable bypass performance and conveying performance and high gravel packing efficiency.

The sand?carrying migration law of slick water in fractures is of great guiding significance to the practice of slick water fracturing.Sand transport profiles with different injection parameter combinations were tested by a visual parallel plate fracture simulator.The results show that the sand?carrying capacity of the slick water is favorable under the combination of slick water for fracturing +70~140 mesh proppant +8% sand ratio.In this case,no sand banks are observed at the fracture inlets,and the proppant does not fill the fractures adequately,under the combinations of low?viscosity slick water +40~70 mesh proppant +10% sand ratio and high?viscosity slick water +20~40 mesh proppant +20% sand ratio, the amount of sand filling fractures is large, and the sand banks in deep fractures are high,while the filling at fracture inlets is poor.With the increase in construction displacement, the various combination modes all exhibit growing positions of the front edges of the sand banks, decreasing heights of front edges, and insignificant changes in balance heights. Injection combination is an important aspect affecting the sand bank pattern. The sand bank patterns and characterization parameters corresponding to different injection parameter combination modes vary greatly. Therefore, the combination mode needs to be optimized on site to improve the conductivity of fractures at the inlet.

CeO₂?modified three?dimensional nitrogen? and phosphorus?doped carbon?based catalysts (CeO₂?NPC) were prepared with cerium chloride hexahydrate as the precursor,sodium chloride as the template,and milk as the carbon source.The results of rotating disc electrode (RDE) and rotating ring?disc electrode (RRDE) tests were used to analyze the influence of catalyst preparation conditions on the oxygen reduction reaction (ORR) process.The influence of the synthesis process on the structure was investigated by X?ray photoelectron spectroscopy (XPS) and Raman spectroscopy.Heteroelements such as N and P spilled out with small molecules during calcination temperature increase.In this process,the degree of defects on the carbon carriers was increasing and the content of CeO₂ was invariably in an increasing trend.

Supported SnCl₂ is a mercury?ree catalyst for acetylene hydrochlorination.5.0%Sn(acac)₂Cl₂/AC catalyst was prepared by introducing acetylacetone ligand to enhance the catalytic performance of SnCl₂ in acetylene hydrochlorination.The results show that the acetylene conversion of 5.0%Sn(acac)₂Cl₂/AC catalyst is up to 96% under the conditions of acetylene?to?hydrogen chloride molar ratio of 1∶1.1,170 ℃ and GHSV(C₂H₂) of 90 h^-1, which is higher than that of the 5.0%SnCl₂/AC catalyst. The physical and chemical properties of the catalysts before and after the reaction also proved that the introduction of acetylacetone ligand can enhance the acetylene adsorption capacity of the SnCl₂ catalyst and inhibit Sn loss during the reaction.Therefore,the activity and stability of the SnCl₂ catalyst were effectively improved.

Conductive polymers have attracted the interest of scientific researchers due to their high electrical conductivity,light weight,corrosion resistance,and good electrical and optical properties.As a typical conductive polymer,polypyrrole has attracted much attention because of its simple synthesis conditions,good environmental stability,environmental friendliness,and the wide range and tunability of electrical conductivity.However,it suffers from some shortcomings such as difficulties in dissolution and melt and poor mechanical properties and processing properties,which limit its application.Composites formed by polypyrrole and other materials not only improve the original shortcomings of polypyrrole but also combine the advantages of the two to endow the materials with new properties and broaden their application fields.This paper briefly described the main synthesis methods of polypyrrole,analyzed the advantages and disadvantages of each method,and summarized its applications in the fields of supercapacitors,gas sensors,and biological tissue engineering.The paper also discussed the problems facing polypyrrole composites and corresponding solutions and provided an outlook on their future development.

A micropore throat plugging material was prepared by emulsion polymerization. Its structural characteristics were analyzed by Fourier transform infrared (FT?IR) spectrum analysis, Raman spectrum analysis, and thermogravimetric?differential thermal analysis (TG?DTA). The particle size range of the synthesized product was determined by a laser particle size analyzer. The inhibition performance and plugging performance of the micropore throat plugging material were also investigated. The results show that the thermal decomposition temperature of the synthesized product is 321.0 °C and that its particle size distribution is between 500 nm and 2 250 nm. When the quantity of the micropore throat protection material used is 1.5%, it performs excellently in inhibiting clay hydration. Moreover, the inhibition effect significantly improves when the micropore throat plugging material is compounded with 0.5% sodium chloride. The filter membrane plugging experiment proves that the filter membrane with a pore diameter of 0.45~10.00 μm can be effectively plugged by the proposed material, and the plugging time is up to 35.43 min when the plugging quantity is 1.5%. After aging at 120 °C for 16 h, the high temperature and high pressure filtration loss is 10.0 mL when the amount of the micropore throat plugging material added is 1.5%.

A self?made long?chain cationic surfactant (SFC111) and a low interfacial energy substance (SFC115) were used to prepare a cationic emulsion for further application as surfactant for low permeability oil and gas reservoirs. The dispersion of the emulsion in water, the contact angle of the core before and after the emulsion treatment and the surface tension were investigated by particle size analyzer, contact angle meter, and rotating drop interfacial tension meter, respectively. The thermodynamic parameters of the emulsion at 20 ℃ and 70 ℃ were calculated. Particle size of 0.5% concentration emulsion is D₅₀=420.8 nm at 20 ℃, D₅₀=728.0 nm at 70 ℃.The contact angle of clear water on the surface of the core increases from 10° to 120°. The emulsion could reduce the surface tension of water to 24 mN/m at 70 ℃, indicating the good waterproof lock performance. The adsorption characteristic of emulsion conforms to the langmuir adsorption theory. The thermodynamic results show that as the temperature increases, the amount of adsorption on the surface of the emulsion decreases, the area occupied by the molecules on the surface of the emulsion goes down, and the thickness of the adsorption layer decreases.

Given the deep burial depth,high temperature and high pressure, significant heterogeneity of the deep gas reservoirs in the southern margin of the Junggar Basin,the temporary plugging and diverting stimulation technology with stratification and segmentation was used to achieve efficient stimulation and improve the producing degree of those reservoirs.The plugging of fractures and perforations by temporary plugging agents under the high temperature of 140~180 ℃ was experimentally investigated,and the degradation rates and pressure?bearing capacities of five temporary plugging materials were evaluated respectively.The results show that the commonly used temporary plugging materials will soften under a high temperature and tend to flow with the carrying fluid under the displacement pressure difference, resulting in a decreased pressure?bearing capacity of the temporary plugging section and the loss of plugging effect. A temporary plugging material with a pressure?bearing capacity of 30.00 MPa at 180 ℃ was selected, and its field application results showed that the temporary plugging improved production significantly.

Accurately predicting the power consumption of crude oil pipelines is conducive to controlling the energy consumption level of such pipelines and fully tapping the energy saving potential of crude oil pipeline transportation systems. Actual operation data of such pipelines have the characteristics of large fluctuation range serious noise interference, and information redundancy, which affect the accurate prediction of pipeline power consumption. To solve these problems, this paper proposes a power consumption prediction model based on a hybrid neural network. The daily operation data of crude oil pipelines are decomposed by complete ensemble empirical mode decomposition with adaptive noise. Principal component analysis is performed to reduce the dimensions of the decomposed data. The improved particle swarm optimization algorithm is applied to adjust the structural parameters of the neural network. The proposed model is applied to predict the power consumption of a crude oil pipeline and compared with some common prediction models. The results show that the decomposition algorithm can improve the prediction accuracy of the model. The hybrid neural network model has the highest prediction accuracy. The average absolute error of the test set is 5.394%, which is 39.200% lower than that before the decomposition algorithm is used.

To evaluate the consequences of leakage accidents of the shallow subsea natural gas pipeline, this paper builds a calculation model of the shallow subsea pipeline leakage and diffusion process in light of computational fluid dynamics and multiphase flow theories for the strait?crossing section of a natural gas pipeline abroad. Three main factors, leakage aperture, leakage rate, and water flow velocity, are selected as condition variables to simulate the motion process of the gas?liquid two?phase flow under different conditions. The results show that underwater gas diffusion can be divided into three stages: the formation of gas masses above the leakage hole, the mushroom?like rise of gas masses, and the splitting of gas masses from large bubbles into small ones. Leakage aperture and leakage rate have a significant effect on the time when the underwater gas diffuses to the water surface. A larger leakage aperture and a higher leakage rate lead to a larger gas leakage amount, which further results in larger volumes of underwater air masses and ultimately a shorter time for them to reach the water surface. Water flow velocity has a significant effect on gas diffusion trajectory. As water flow velocity increases, the angle between the gas trajectory and the seabed decreases, and the diffusion distance along the ocean current direction becomes longer. This study can provide scientific guidance for emergency treatment of underwater natural gas pipeline leakage accidents.

Li₂ZnTi₃O₈ anodes coated with N?doped carbon from dopamine hydrochloride were synthesized via a high?temperature solid?state method.Some Ti⁴⁺ ions were reduced to Ti³⁺ ions during synthesis,which enabled the co?modification of coating and doping.The modification method can enhance the ion diffusion coefficients and reduce the charge?transfer resistance.In the rate performance tests at 0.5,1.0,1.5,2.0,2.5,3.0 A/g,the specific capacities of N?doped carbon?coated Li₂ZnTi₃O₈(Li₂ZnTi₃O₈@C?N?2) are over 240.0，220.0，210.0，200.0，190.0，180.0 mA ? h/g,respectively.In addition,the electrochemical performance of this material at a low temperature was also studied.The results show that the Li₂ZnTi₃O₈@C?N?2 sample has much higher discharge specific capacities than those of unmodified Li₂ZnTi₃O₈ anode material at 0 ℃.The initial discharge specific capacity is 262.5 mA ? h/g at 0.2 A/g,and the discharge specific capacity of 241.7 mA ? h/g is still obtained after 300 cycles.Even at 1.0 A/g,the discharge specific capacity is kept at 147.4 mA ? h/g after 300 cycles.

Mg?Al?LDH was synthesized by the constant pH co?precipitation method,and the micro?structure and composition of the layered bimetallic hydroxides were characterized by X?ray diffraction (XRD),scanning electron microscopy (SEM),energy dispersive spectroscopy (EDS) and BET.The results show that LDHs were successfully prepared with a layered structure,a high degree of order,and mesopores.The toluene?n?heptane method was used to separate the asphaltenes in Tahe into heavy component A₁ and light component A₂.The elemental analysis indicates that A₁ had the highest polarity,followed by the Tahe asphaltenes and A₂.This paper further investigated the adsorption properties of Mg?Al?LDH for asphaltenes and their sub?components A₁ and A₂ in Tahe and found that the adsorption equilibrium can be reached within 2~3 h.The experimental data fitted well with the pseudo?second?order kinetics,and the adsorption isotherms followed the Langmuir model. The adsorption capacity of Mg?Al?LDH was 71.38,140.65 and 39.31 mg/g for asphaltenes in Tahe and their sub?components A₁ and A₂,respectively.

A combined chemical cleaning?thermal steam air floatation process was established to treat oil sludge,and the conditions of the combined process were investigated meticulously. Meanwhile, the self?synthesized WP?1 was taken as the main cleaning agent, and the cleaning effect of WP?1 was evaluated by the solid?phase oil content upon treatment. The results reveal that the optimal conditions for the combined process include a mud?to?water ratio of 1 : 3, a cleaning temperature of 80 ℃, an agitation rate of 200 r/min, cleaning time of 1.5 h, holding time of 15.0 min, and thermal steam air floatation of 1.0 h. Thermal steam air floatation solves the problem of suspending and sinking oil particles with large specific gravity in the cleaning process. Under optimal conditions, the solid?phase oil content decreases to 1.2%, meeting the oil sludge treatment standards stipulated in SY/T 7301-2016. The oil removal rate is as high as 92.08% when WP?1 is combined with 0.1 g of sodium silicate, which demonstrates a high price?performance ratio and is of good application value.

In order to investigate the oxidation and degradation effect of potassium on naphthalene,the main factors affecting the degradation rate of naphthalene were determined by single factor experiments,and the degradation conditions of naphthalene were optimized by response surface analysis.The results show that the best degradation condition of potassium ferrate for mass concentratoion of 5.0 mg/L naphthalene are as follows:the temperature is 25 ℃,the pH is 7.0, the dosage of potassium ferrate is 0.60 g/L,and the react time is 30 min.Under the optimum oxidation degradation condition,the rate of naphthalene is 75.60%.The results of single factor experiment show that pH(A),the initial mass concentration of naphthalene(B), and the potassium ferrate dosage(C) are the main factors affecting the degradation rate of naphthalene,and the degree of influence is from big to small C>B>A.The results of multifactor experiment show that the order of interfactors from big to small is AC>AB>BC.The model predicted the optimal degradation conditions of naphthalene by potassium perferrate:the temperature is 25 ℃,the initial mass concentration of naphthalene is 2.79 mg/L and the pH is 6.8,the mass concentration of potassium ferrate is 0.90 g/L,and the reaction time is 30 min.Under the optimum degradation conditions,the highest degradaton rate of naphthalene is 91.82%.

A nitrogen?doped carbon catalyst was prepared by the calcination of the CN _y precursor synthesized by the polymerization of paraformaldehyde,1,3,5?trimethylbenzene and p?phenylenediamine.This paper also investigated the effect of catalyst calcination temperature on the performance of acetylene hydrochlorination.The results indicate that CN _y ?700?1 catalyst has the best reaction activity.It has an acetylene conversion of up to 89.8% under the optimized conditions of acetylene?to?hydrogen chloride volume ratio of 1.0∶1.1,reaction temperature of 280 ℃ and GHSV(C₂H₂) of 90 h^-1.The catalyst characterization manifests that the activity of the catalyst is related to the specific surface area,pore volume,and pyrrole nitrogen content.The active site of the catalyst is the carbon atom bonding with the pyrrole nitrogen atom.Increasing the calcination temperature results in a larger specific surface area within a certain temperature range,and the pyridine nitrogen can also be converted to pyrrole nitrogen to a certain extent.The main cause of catalyst deactivation is carbon deposit.

Layered double hydroxides (LDHs),also known as hydrotalcite,can be widely employed in water pollution treatment because of their special layered structures,high physicochemical stability,and electronic properties.The application of LDH composites as catalysts for photocatalysis has received increasing attention.Therefore,the preparation and modification of LDH photocatalysts were reviewed,and the removal effect of pollutants from wastewater exerted by different LDHs was emphatically introduced.In addition, the mechanism and research status of LDH photocatalysts were briefly described.Finally,the development trend of LDH photocatalysts was prospected to provide a reference for the subsequent application of LDHs in water pollution treatment.

A ZnO nanoflower hybrid material loaded with NiO nanoparticles was presented,and then it was investigated in XRD, morphology and gas sensing properties.The results show that surface loaded NiO nanoparticles modulated the electric channel of ZnO nanoflowers.The response value of heterojunction gas sensing material with optimized NiO loading amount to xylene is increased by 3.3 times compared with that of pristine ZnO.In addition,the selectivity of the sensor is enhanced and response time decreases.From a broader perspective,the methods for functionalized gas sensors of high?performance semiconductor metal oxide (SMOX) are proposed by introducing surface heterostructure.

A new type of gelator with π?π stacking as weak interaction force was designed and synthesized. Pyromellitic acid esters were synthesized from pyromellitic dianhydride and alcohols of different carbon chain lengths to reduce hydrogen bonding sites.Then the gel capabilities were explored in common different organic solvents.The rheological test shows that the elastic modulus of the gel system is ten folds higher than the storage modulus,indicating that the gel has good mechanical properties and exhibits typical solid?like rheological behavior.Fourier transform infrared spectroscopy,nuclear magnetic resonance spectroscopy,scanning electron microscopy and DSC results show gelators formed fibrous self?assembled aggregates in gel under driving force from π?π stacking and the van der Waals force.The formed aggregates entangle with each other and finally form a three?dimensional network structure that hinders the flow of the solvent to form the gel.

Common wicker,the raw material of biochar,was treated by hexadecyltrimethylammonium chloride (CTMAC) for cationic surface activation,and then it was mixed with zero?valent iron and sodium alginate to prepare zero?valent iron/cationic surfactant/biochar (Fe⁰?MBC) gel microspheres, and their ability to adsorb Cr(VI) in water was discussed.The structure and properties of Fe⁰?MBC gel microspheres were studied by means of XRF,FTIR,XRD and Zeta potential.Upon the analysis of the effects of the reaction time,temperature and pH value on adsorption,the adsorption mechanism was preliminarily discussed on the basis of adsorption kinetics and the isotherm model.The results indicate that the adsorption effect of Fe⁰?MBC gel microspheres on Cr(VI) is highly fitted with that of pseudo?first?order kinetics and the Langmuir isothermal adsorption model. The removal rates of Cr(VI) by CTMAC?activated biochar loaded with 5% zero?valent iron and CTMAC?activated biochar loaded with 10% zero?valent iron can reach 89% and 97% (initial Cr concentration of 100 mg/L) at 2 h, respectively, and the maximum saturated adsorption capacities are 33.777 9 mg/g and 42.562 0 mg/g, respectively.The experimental results reveal that Fe⁰?MBC gel microspheres, as a low?cost and high?efficiency environmental functional material, have good application prospects for the removal of Cr(VI) in wastewater.

The strong stress sensitivity of low permeability oilfield reservoirs leads to serious permeability loss,larger starting pressure gradient,and higher seepage resistance,thereby reducing the water?flooding effects of oilfields.The existing prediction models for water breakthrough time do not consider the stress sensitivity and variable starting pressure gradient at the same time,which results in inconsistency between calculation results and actual situation of mines.Therefore,for the first time,this paper deduced the prediction models for the water breakthrough time of well pattern of five point method,four point method,and inverse nine point method in the condition of unequal row spacing and well spacing considering stress sensitivity and variable starting pressure gradient.The calculation results show that the error of the new model is relatively small,which is more in line with the field practice.The results can guide the adjustment of block measures and provide theoretical support for improving the development of water drive oilfields.

As an important method of reservoir parameter calculation and single well controlled reserves evaluation, production decline analysis has been widely used in conventional and unconventional reservoir evaluation and dynamic reserve calculation. However, researches on heavy oil reservoir production decline analysis model have rarely been reported. Therefore, based on the unsteady seepage theory, an unsteady mathematical model of radial composite reservoir with Newtonian and power law fluid is established to get NPI and Blasingame production decline characteristic curves. The results show that the characteristic curves can be divided into four flow stages, including Newtonian fluid radial flow stage, transition flow stage, power?law fluid radial flow stage and pseudo?steady?state flow stage. The NPI integral derivative curve of power?law fluid radial flow stage is a straight line with slope of (1-n)/(3-n). The higher the power?law index and mobility ratio indicates the larger value of power?law fluid flow phase curve. The accuracy of the model is verified by fitting the measured data from Liaohe Oilfield.

A high tide velocity makes it difficult for the riser to enter the borehole during its running after the riser section is drilled. A finite?element fluid?solid coupling model of fluid (seawater) and solid (casing) interaction is built with the finite?element analysis software ADINA. The following observations can be made from the analysis. A higher velocity results in a larger lateral offset in the final equilibrium state when the riser enters the borehole.Due to the flow blocking effect of the riser, seawater near the front end of the riser produces a strong detouring flow, while a local vortex is observed in the area near the back end of the riser.Under four working conditions of different tide velocities (0.60,0.70,0.80 and 0.90 m/s), both the Reynolds number and the equivalent flow resistance coefficient are in reasonable ranges.When the borehole diameter reaches 889.0 mm after borehole enlargement, a 508.0 mm riser is run in. No obstruction is encountered when the tide velocity is less than 0.59 m/s, whereas difficult borehole entering occurs when the tide velocity is higher than 0.83 m/s. It is suggested that the riser will be run in when the tide velocity reduces to below 0.59 m/s. The simulation analysis has a great guiding significance for the running of the riser during the drilling of offshore oil fields.

Excessive CO₂ emission caused by a large number of human activities is the main cause of global warming,so a method to effectively control the increase in CO₂ concentration is urgently needed.Currently,direct air capture is the only technology capable of achieving negative growth of carbon emissions on a large scale.Solid amine adsorbents,especially silicon?based ones, have been widely studied and used to capture CO₂ from ambient air due to their advantages of high adsorption capacity,corrosion resistance,and low energy consumption.In this paper,silicon?based solid amine adsorbents were classified according to the mode of loading,and the influence of different silicon?based supports on the adsorbent performance was summarized.At the same time,the problems encountered in the industrial application of powdered solid amine adsorbents were put forward,and the current forming methods of solid amine adsorbents were sorted out.Finally,it is pointed out that the development of formed solid amine adsorbents with high adsorption capacity and high stability is the future trend of CO₂ adsorbent industrialization.

The adsorption data of hydrogen in graphene,single?walled carbon nanotubes,and multi?walled carbon nanotubes at 293.15 K and 101.30 kPa were measured experimentally.Through the comparison of the data calculated by different force fields under the same conditions, the optimal force fields of the three carbon materials for calculation were selected.On this basis,the hydrogen adsorption data of the three carbon materials at 0~1 000.00 kPa and 77.00~573.15 K were calculated.The results show that the Dreiding force field is the optimal force field to calculate the hydrogen adsorption and storage in graphene,and the Universal force field is the best force field to calculate that in carbon nanotubes.Under given conditions,the hydrogen adsorption and storage capacity of the three materials is ranked as follows:graphene single?walled carbon nanotubes multi?walled carbon nanotubes.The hydrogen storage capacity is closely related to the specific surface area of the material and its weak binding force with hydrogen.The results can provide data and theoretical support for the molecular simulation of hydrogen adsorption and storage in carbon materials as well as hydrogen storage material design.

Under the national strategy of carbon peak and carbon neutrality in China,utilizing CO₂ for enhanced oil recovery becomes an important means of CO₂ storage in oilfields. However, there are still challenges in the safe storage and transportation of liquid CO₂,in which gas impurities have a great influence on the thermodynamic properties of liquid CO₂.Seven common gas impurities were determined by the analysis of CO₂ samples obtained in the field,and the changes in physical properties of the CO₂ samples containing impurities were simulated by HYSYS and the molecular dynamics simulation method.The physical property diagrams were plotted and compared with those of pure CO₂.The results reveal that all seven impurities can enlarge the gas?liquid coexisting region in CO₂ phase diagrams,but the enlargement extent differs. The impurities mainly expand the gas?liquid coexisting region by changing the bubble point line,while the dew point line has little change.It is found by molecular dynamics simulation that the electrostatic potential energy plays a dominant role in the CO₂ mixture containing C₂H₆,C₃H₈,and C₂H₄.Therefore,compared with the results of the mixture containing H₂,CO,CH₄,and carbonyl sulfur (OCS),its macroscopic physical properties are less affected by temperature and pressure fluctuations.

In order to study the influences of swing, H₂O and N₂ on the removal of CO₂ from offshore natural gas by adsorption and purification, dynamic penetration experiments of mixed multi?component gas in the dry and aqueous 13X zeolites under static and swing conditions were carried out. Mixtures of CH₄/ CO₂ and CH₄/ CO₂/ N₂ were obtained by matching CH₄, CO₂, and N₂ in proportion through a mass spectrometer. In addition, under static and swing conditions, the partial pressure of each gas in the mixtures at the exit of the dry and aqueous 13X zeolites at different time was measured during dynamic penetration experiments, and the penetration curve and penetration time were obtained. The adsorption and purification effect of CO₂ in the two mixtures in the dry and aqueous 13X zeolites under the two conditions was analyzed according to the penetration time, and then the influences of swing, H₂O and N₂ on the removal of CO₂ from offshore natural gas by adsorption and purification were clarified. The experimental results show that 13X zeolites have the strongest capacity in absorbing CO₂ and the weakest capacity in absorbing N₂ under static or swing conditions. N₂ is conducive to the removal of CO₂ from offshore natural gas by adsorption and purification, while the swing and H₂O fail to do so.

A deep eutectic solvent was synthesized by the stirring method with Br?nsted acid (carboxylic acid) and Lews acid (ferric chloride) as raw materials. It was then analyzed with a Fourier transform infrared (FTIR) spectrometer. The results showed that the deep eutectic solvent was formed by hydrogen bonding between Br?nsted acid and Lews acid. Extraction desulfurization with this deep eutectic solvent as the extractant was investigated, and the optimum desulfurization conditions were obtained as follows. When the molar ratio of Br?nsted acid to Lews acid is 1 : 0.5, the desulfurization temperature is 30 °C, and the ratio of solvent to oil is 1 : 5, the proposed extractant demonstrates a favorable desulfurization effect on the simulated oil, gasoline, and diesel.

Titanium dioxide (TiO₂) is a traditional photocatalyst material.However, due to its wide band gap (3.2 eV) and the easy recombination of photogenerated carriers,it is necessary to enhance the effective absorption of sunlight,promote the separation of photogenerated carriers,and inhibit their recombination by doping noble metals,transition metals,anions and constructing heterojunctions.TiO₂/CdS heterojunctions were prepared in two steps.Firstly,TiO₂ nanotube arrays were prepared by multiple voltage anodization.Then,with TiO₂ nanotubes as the base,CdS quantum dots were uniformly deposited inside and outside the nanotubes through chemical bath deposition.The composition,morphology,and optical properties of TiO₂/CdS heterojunctions were characterized by X?ray diffraction,scanning electron microscopy (SEM),transmission electron microscopy (TEM),X?ray photoelectron spectroscopy (XPS),and UV?visible spectroscopy (UV?VIS).The prepared TiO₂/CdS heterojunctions effectively inhibited the recombination of photogenerated carriers,promoted the transfer of excited electrons,and improved the hydrogen production efficiency by photocatalysis.The hydrogen production efficiency of sample TiO₂(1.0)?CdS(1.0) reached 1.30 mmol/（g ? h）,which was 1.67 times that of CdS quantum dots.Finally,according to the experimental analysis,the transfer mechanism of photogenerated electrons on TiO₂/CdS during photocatalytic water splitting for hydrogen was proposed.

The BaTiO₃?TiO₂ composites were prepared by using hydrate barium hydroxide (Ba(OH)₂·8H₂O) and titanium dioxide (TiO₂) as raw materials with soft chemical hydrothermal method at 120 ℃ and different Ba/Ti molar ratios.The structure of the prepared composites with different Ba/Ti molar ratios was analyzed by X?ray diffraction (XRD),scanning electron microscopy (SEM),and UV?visible absorption spectroscopy (UV?Vis),the degradation effect of the complex on the simulated degradation pollutant,rhodamine B (RhB) was investigated.The results indicate that the BaTiO₃?TiO₂ composites obtained at a Ba/Ti molar ratio of 0.50 have an excellent catalytic effect for the degradation of rhodamine B (RhB) during the simulation of dye wastewater degradation.Meanwhile,more active sites formed at the Ba/Ti molar ratio of 0.50, which facilitated the photocatalytic reaction.

Electrochemical treatment technologies have been widely used to remove heavy metals in water.Specifically,carbon?based electrodes show positive application prospects in electrochemical treatment and recovery of heavy metals due to their strong electrical conductivity,large specific surface area,and controllable structure.This paper reviewed the research progress in the removal and recovery of heavy metals in electrochemical fields,such as electro?adsorption,electro?reduction,electro?oxidation,and electro?deposition by carbon?based electrodes including carbon nanotubes,graphene,and activated carbon.In addition,the development trends of removing heavy metals by electrochemical treatment technologies based on carbon materials were predicted.

A block in Changqing oilfield has high heterogeneity,and there are high?capacity channels, microfractures and high?permeability zones in its formations. During the implementation of natural gas flooding, the high risk of gas channeling must be considered. The traditional polymer microspheres are characterized by fast water absorption and expansion rate.It is easy to shear and crush its plugging strength is low. In view of these shortages,a polymer microsphere featuring delayed swelling was thus synthesized by introducing and activating a crosslinker and adopting inverse emulsion polymerization to address those defects. Its structure was characterized by a laser particle size analyzer and a polarizing microscope. Laboratory experiments were conducted to systematically evaluate the performance of the polymer microsphere featuring delayed swelling in temperature resistance,salt resistance,swelling,stability,and plugging during natural gas flooding.The results show that with a temperature resistance of 85 ℃, a salt resistance of 100 000 mg/L, a swelling time delay of 7 days, a particle size enlargement factor of 5.5, long?term stability (more than 6 months), and a plugging rate of more than 92.0%, the proposed polymer microsphere featuring delayed swelling can be used for plugging deep microfractures and high?permeability zones in the formations.

The expansion of the swept volume of injected water by polymers in the porous medium is the main mechanism for polymer flooding to increase oil recovery.The transport of polymer and the oil displacement effect were investigated.Experiments have shown that there is no positive correlation between the viscosity of the polymer flooding agent and the oil displacement effect.The viscosity of the salt?resistant polymer (52.4 mPa?s) is higher than that of the "high?resolution" polymer (35.6 mPa?s ),but it has poor compatibility with the pore?throat structure of the reservoir and poor injection and shear resistance.The oil displacement experiments demonstrate that the overall recovery increase by salt?resistant polymer flooding (6.94%) is lower than that of "high score" polymer flooding (18.94%). Therefore, compared with the "high?score" polymer of "equal viscosity" or "equal concentration", the salt?resistant polymer has a worse ability to expand the swept volume.