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Chemical modification of barite for improving the performance of weighting materials for water-based drilling fluids

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Petroleum Science 2024年第1期21卷 551-566页

作者： Li-Li Yang Ze-yu Liu Shi-bo wang Xian-Bo He Guan-Cheng Jiang jie Zhang MOE Key Laboratory of Petroleum Engineering State Key Laboratory of Petroleum Resources and ProspectingChina University of Petroleum(Beijing)Changping DistrictBeijing102249China MOE Key CNPC Drilling Research Institute Changping DistrictBeijing102206China

With increasing drilling depth and large dosage of weighting materials,drilling fluids with high solid content are characterized by poor stability,high viscosity,large water loss,and thick mud cake,easier leading to reservoir damage and wellbore *** this paper,micronized barite(MB)was modified(mMB)by grafting with hydrophilic polymer onto the surface through the free radical polymerization to displace conventional API barite *** suspension stability of water-based drilling fluids(WBDFs)weighted with API barite:mMB=2:1 in 600 g was significantly enhanced compared with that with API barite/WBDFs,exhibiting the static sag factor within 0.54 and the whole stability index of *** viscosity and yield point reached the minimum,with a reduction of more than 40%compared with API barite only at the same *** multi-stage filling and dense accumulation of weighting materials and clays,filtration loss was decreased,mud cake quality was improved,and simultaneously it had great reservoir protection performance,and the permeability recovery rate reached 87%.In addition,it also effectively improved the lubricity of *** sticking coefficient of mud cake was reduced by 53.4%,and the friction coefficient was ***,mMB can serve as a versatile additive to control the density,rheology,filtration,and stability of WBDFs weighted with API barite,thus regulating comprehensive performance and achieving reservoir protection *** work opened up a new path for the productive drilling of extremely deep and intricate wells by providing an efficient method for managing the performance of high-density WBDFs.

关键词： Drilling fluids Weighting materials Filtration control Reservoir protection Stability property

Experimental study on combustion characteristics of supersonic combustor based on alternating-wedge strut

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Chinese Journal of Aeronautics 2024年第5期37卷 214-227页

作者： jie LI Wenyan SONG yuhang wang School of Power Energy Northwestern Polytechnical UniversityXi’an 710129China

Acetone Planar Lase-Induced Fluorescence(PLIF)and OH-PLIF were employed to capture the fuel distribution and OH distribution downstream for the supersonic combustor based on the alternating-wedge *** combustion establishment process and combustion mode in the combustor under different fuel injection methods and different equivalence ratios were *** with the kerosene-PLIF and OH-PLIF results in the cavity combustor,a comparative analysis was conducted to understand the combustion characteristics and combustion modes between the alternating-wedge strut-based combustor and the cavity-based *** results show that the combustor is in weak combustion mode in the case of low equivalence ratio,and the combustor is in intensive combustion mode in the case of high equivalence *** lower limit of the equivalence ratio of the combustor to maintain the intensive combustion mode varies based on different fuel injection *** OH distribution under reacting condition has a strong correlation with the fuel distribution under non-reacting *** OH fluorescence signal near the injector is weaker when the fuel distribution is more *** injector position located at the base of the strut rear has better mixing performance,enabling the combustor to be in intensive combustion mode at a lower equivalence *** combustion reaction in the alternating-wedge strut-based combustor is not necessarily dominated by mass transfer due to the mixing enhancement and premixed zone downstream of strut,while the combustion reaction process in the cavity-based combustor is mainly influenced by mass transfer.

关键词： Supersonic combustor Alternating-wedge strut Cavity PLIF Fuel injection Fuel distribution Combustion characteristics Combustion mode

Boson star superradiance

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 69-78页

作者： He-yu Gao Paul M.Saffin Yi-jie wang Qi-Xin Xie Shuang-Yong Zhou School of Physical Sciences University of Science and Technology of ChinaHefei 230026China School of Physics and Astronomy University of NottinghamUniversity ParkNottingham NG72RDUK Interdisciplinary Center for Theoretical Study University of Science and Technology of ChinaHefei 230026China Peng Huanwu Center for Fundamental Theory Hefei 230026China

Recently,it has been realized that in some systems internal space rotation can induce energy amplification for scattered waves,similar to rotation in real *** particularly,it has been shown that energy extraction is possible for a Q-ball,a stationary non-topological soliton that is coherently rotating in its field *** this paper,we generalize the analysis to the case of boson stars,and show that the same energy extraction mechanism still works for boson stars.

关键词： superradiance boson star field space rotation

Boosting propane dehydrogenation of defective S-1 stabilized singleatom Pt and ZnO catalysts via coordination environment regulation

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Nano Research 2024年第7期17卷 5884-5896页

作者： Fuwen Yang jie Zhang Jinwei Chen Gang wang Tong yu Qian Li Zongbo Shi Qiushi Sun Runsheng Zhuo Ruilin wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China Engineering Research Center of Alternative Energy Materials&Devices Ministry of EducationSichuan UniversityChengdu 610065China REZEL Catalysts Corporation Shanghai 200120China

Pt single atoms catalysts with precise coordination environment and high stability are expected to achieve high performance of propane dehydrogenation(PDH).In this work,an innovative synthetic strategy is proposed to construct the S-1@0.1Pt9Zn@DPS-1 nanocomposite as a highly efficient PDH *** engineering is applied to induce the formation of defective porous silicalite-1(DPS-1),which is favorable for achieving the uniformly distributed ZnO *** ZnO nanoclusters were further served as anchoring sites to stabilize the isolated Pt *** structural characterization revealed that penta-O coordinated Pt single atom coupled with ZnO nanoclusters decorated on the ***,the atomically dispersed Pt atoms with the ideal coordination environment could act as the predominant active sites for PDH *** expected,the optimal S-1@0.1Pt9Zn@DPS-1 catalyst delivered an excellent PDH performance(propane conversion of 40.7%,propylene selectivity of 97.5%)and good cycling regeneration *** work provides a new way for improving the activity and stability of catalysts in the field of industrial catalysts.

关键词： defect engineering single platinum atom coordination environment propane dehydrogenation propylene

Revealing the size effect of Fe S2on solid-state battery performances at different operating temperatures

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Chinese Chemical Letters 2024年第6期35卷 189-194页

作者： Chaochao Wei Ru wang Zhongkai Wu Qiyue Luo Ziling Jiang Liang Ming jie Yang Liping wang Chuang yu School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China

FeS_(2) shows significant potential as cathode material for all-solid-state lithium batteries(ASSLBs)due to its high theoretical specific capacity,low cost,and environmental ***,the poor ion/electron conductivity and large volume variation effect of FeS_(2) inhibit its practical ***,the influence of particle size of FeS_(2) on the corresponding sulfide-based solid-state batteries is carefully investigated by tuning FeS_(2) ***,low operating temperature is chosen to mitigate the large volume changes during cycling in the battery.S-FeS_(2) with smaller particle sizes delivers superior electrochemical performances than that of the larger L-FeS_(2) in Li_(5.5)PS_(4.5)Cl_(1.5)-based ASSLBs under different operating temperatures.S-FeS_(2) shows stable discharge capacities during 50 cycles with a current density of 0.1 m A/cm^(2)under -20℃.When the current density rises to 1.0 m A/cm^(2),it delivers an initial discharge capacity of 146.9 m Ah/g and maintains 63% of the capacity after 100 *** work contributes to constructing ASSLBs enables excellent electrochemical performances under extreme operating temperatures.

关键词： FeS_(2) Size effect Li_(5.5)PS_(4.5)Cl_(1.5) electrolytes Operating temperatures Electrochemical performances

Rebuilding the theory of isotope fractionation for evaporation of silicate melts under vacuum condition

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Acta Geochimica 2024年第4期43卷 661-676页

作者： jie wang yun Liu Research Center for Planetary Science College of Earth and Planetary SciencesChengdu University of TechnologyChengdu 610059China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China CAS Center for Excellence in Comparative Planetology Hefei 230026China

Isotope eff ects are pivotal in understanding silicate melt evaporation and planetary accretion *** on the Hertz-Knudsen equation,the current theory often fails to predict observed isotope fractionations of laboratory experiments due to its oversimplified ***,we point out that the Hertz-Knudsen-equation-based theory is incomplete for silicate melt evaporation cases and can only be used for situations where the vaporized species is identical to the one in the *** propose a new model designed for silicate melt evaporation under *** model considers multiple steps including mass transfer,chemical reaction,and *** derivations reveal a kinetic isotopic fractionation factor(KIFF orα)αour model=[m(^(1)species)/m(^(2)species)]^(0.5),where m(species)is the mass of the reactant of reaction/nucleation-limiting step or species of diffusion-limiting step and superscript 1 and 2 represent light and heavy isotopes,*** model can eff ectively reproduce most reported KIFFs of laboratory experiments for various elements,i.e.,Mg,Si,K,Rb,Fe,Ca,and ***,the KIFF-mixing model referring that an overall rate of evaporation can be determined by two steps jointly can account for the eff ects of low P_(H2)pressure,composition,and *** addition,we find that chemical reactions,diffusion,and nucleation can control the overall rate of evaporation of silicate melts by using the fitting slope in ln(−ln f)versus ln(t).Notably,our model allows for the theoretical calculations of parameters like activation energy(E_(a)),providing a novel approach to studying compositional and environmental eff ects on evaporation processes,and shedding light on the formation and evolution of the proto-solar and Earth-Moon systems.

关键词： Evaporation Kinetic isotopic fractionation Chemical kinetics Hertz-Knudsen equation CAIS

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Electronic structure regulation and built-in electric field synergistically strengthen photocatalytic nitrogen fixation performance on Ti-BiOBr/TiO_(2)heterostructure

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Rare Metals 2024年第3期43卷 1125-1138页

作者： Ru-Qi Li yu-jie Bian Chun-Ming Yang Li Guo Tao-Xia Ma Chuan-Tao wang Feng Fu Dan-Jun wang College of Chemistry and Chemical Engineering Yan’an UniversityYan’an Key Laboratory of Green Catalysis and Quality Improvement and Utilization of Low Rank CoalYan’an716000China

At present,industrial synthetic ammonia was still obtained through the Hubble-Bosch process,with large energy *** is a research hotspot to realize green synthetic ammonia by using solar *** difficulty of photocatalytic ammonia synthesis was that the photo-excited electrons have not enough energy to active N≡*** this study,Ti was doped into BiOBr by one-step hydrothermal method,which was oxidized into TiO_(2)when the doping amount reaches the maximum,in situ forming Ti_(0.31)B_(0.69)OB/TiO_(2)*** from the synergistic effect of Ti doping and S-scheme heterojunction,the synthetic ammonia efficiency of Ti_(0.31)B_(0.69)OB/TiO_(2)-11.96 reached 1.643 mmol·g_(cat)^(-1)at mild conditions and without hole scavenger for up to 7 h,the efficiency of synthetic ammonia is 115 times,10.5 times and 3.3 times of that of BiOBr,Ti_(0.31)B_(0.69)OB and TiO_(2),***,DFT calculation confirms that Ti doping accurately refine the electronic structure of BiOBr,facilitate nitrogen adsorption activation and reduce hydrogenation reaction energy barrier,thus accelerating the reaction kinetics of photocatalytic nitrogen reduction(NRR),Meanwhile,constructing S-scheme heterojunction boosts the separation and transfer of photogenerated electron-hole pairs,improving the reduction ability of electrons in the conduction band of TiO_(2)and the oxidation ability of holes in the valence band of Ti_(0.31)B_(0.69)OB.

关键词： S-scheme heterostructure Electronic structure regulation Built-in electric field Synergistical stren4gthening Photocatalytic nitrogen fixation

A guidance and control design with reduced information for a dual-spin stabilized projectile

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Defence Technology（防务技术） 2024年第3期33卷 494-505页

作者： yu wang Jiyan yu Xiaoming wang Jia Fangxiu Intelligent Ammunition Technology National Defense Key Discipline Laboratory Nanjing University of Science and TechnologyNanjingJiangsu210094China

In this paper,an integrated guidance and control method based on an adaptive path-following controller is proposed to control a spin-stabilized projectile with only translational motion information under the constraint of an actuator,uncertainties in aerodynamic parameters and measurements,and control system *** to the fairly high rotation speed,the dynamic model of this missile is strongly nonlinear,uncertain and coupled in pitch,yaw and roll channels.A theoretical equivalent resultant force and uncertainty compensation method are comprehensively used to realize decoupling of pitch and *** response to the strong nonlinear and time-varying characteristics of the dynamic system,the quasi-linear model whose parameters are obtained by interpolation of points selected as the segmentation points in the trajectory envelope,is used for calculation in each *** cope with the system uncertainty caused by model approximation,parameter uncertainty and ballistic interference,an extended state estimator is used to compensate the output feedback according to the test ballistic *** order to improve the tracking efficiency and ensure the tracking error convergence with only translational motion information,the virtual guide point,whose derivative is deduced according to the Lyapunov principle,is calculated in real time according to the projection relationship between the real-time position and the reference trajectory,and a virtual line-of-sight angle and the backstepping method are used for the design of the guidance and control *** order to avoid the influence of control input saturation on the guidance and control performance due to the actuator limitation and improve the robustness of the system,an anti-saturation compensator is designed according to the two-step *** feasibility and effectiveness of the path-following controller is verified through closed-loop flight simulations with measurement,control,and condition *** result

关键词： Spin-stabilized projectile Reduced information Path-following control Extended state observer Coupled nonlinear system Input saturation

移动床生物膜反应器-生物滤池脱氮除磷中试研究

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山东农业大学学报（自然科学版） 2024年第1期55卷 131-136页

作者：侯祥东王洁宇刘爱国王浩宇董坤明李妮孙甲玉山东省海河淮河小清河流域水利管理服务中心山东济南250001 山东农业大学水利土木工程学院山东泰安271018 水发规划设计有限公司山东济南250001

采用移动床生物膜反应器-生物滤池(MBBR-BF)一体化污水处理设备进行实际污水中试试验,考察曝气量对一体化设备挂膜启动阶段污染物去除效果的影响,探究低温环境下一体化设备适应性及污染物处理能力。结果表明:曝气量降低对COD和TN去除率... 详细信息

采用移动床生物膜反应器-生物滤池(MBBR-BF)一体化污水处理设备进行实际污水中试试验,考察曝气量对一体化设备挂膜启动阶段污染物去除效果的影响,探究低温环境下一体化设备适应性及污染物处理能力。结果表明:曝气量降低对COD和TN去除率影响较小,而NH_(3)-N与TP的去除率随之下降,NH_(3)-N平均去除率由87.46%降至48.64%,TP平均去除率由72.41%降至54.66%;常温环境下COD、NH_(3)-N、TN、TP平均去除率分别为92.48%、94.41%、49.39%和61.63%,低温环境运行对污染物去除效果有明显影响。中试应用试验状况良好,一体化设备在冬季低温环境下运行状况正常,可为农村生活污水的有效处理提供重要参考。

关键词：脱氮除磷污水处理设备曝气量环境温度