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Defence Technology（防务技术） 2024年第6期36卷 20-29页

作者： Huixin wang Qiang li Hui ren liangjun Xie Tingting liu zhihong Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Inner Mongolia Institute of Synthetic Chemicals Hohhot 010010China

Coating modification is an important way to enhance the reactivity of aluminum *** this paper,ammonium perchlorate and aluminum powder were assembled into energetic microunits by liquid deposition *** particles with AP as shell and ultrafine aluminum powder as the core(Al@AP)were *** micromorphology results show that the coated particles are about 5μm,and the coating layer is evenly distributed on the outer surface of aluminum powder,indicating a complete *** energetic microunits were implanted into the nitrate ester plasticizing adhesive system(NEPE)as solid phase *** effect of filler on the rheological properties,safety,mechanical properties,thermal reaction and energy properties of the system was analyzed by comparing with the raw aluminum *** test results show that the rheological properties,mechanical properties and pressure index of NEPE containing system Al@AP meets the requirements of solid propellant *** with Al based propellant,the mechanical sensitivity and thermal sensitivity are decreased,the safety is better,and the explosion heat of the propellant is increased by 7.8%.The engine test shows that the specific impulse is increased by 1.2 ***@AP can improve the energy output and safety of NEPE propellant,and has potential application prospects in high-energy propellants.

关键词： Aluminum powder Coating NEPE propellant Energy output Applied research

Hybrid ion/electron interfacial regulation stabilizes the cobalt/oxygen redox of ultrahigh-voltage lithium cobalt oxide for fast-charging cyclability

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Science Bulletin 2024年第13期69卷 2071-2079页

作者： zhihong Bi Anping Zhang Gongrui wang Cong Dong Pratteek Das Xiaoyu shi Zhong-Shuai wu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China Dalian National Laboratory of Clean Energy Chinese Academy of SciencesDalian 116023China

High-voltage and fast-charging liCoO_(2)(LCO)is key to high-energy/power-density li-ion ***,unstable surface structure and unfavorable electronic/ionic conductivity severely hinder its high-voltage fast-charging ***,we construct a li/Na-B-Mg-Si-O-F-rich mixed ion/electron interface network on the 4.65 V LCO electrode to enhance its rate capability and long-term cycling ***,the resulting artificial hybrid conductive network enhances the reversible conversion of Co^(3+)/^(4+)/O_(2)/nredox by the interfacial ion–electron cooperation and suppresses interface side reactions,inducing an ultrathin yet compact cathode electrolyte ***,the derived near-surface Na+/Mg2+/Si^(4+)-pillared local intercalation structure greatly promotes the li^(+)diffusion around the 4.55 V phase transition and stabilizes the cathode ***,excellent 3 C(1 C=274 mA g1)fast charging performance is demonstrated with 73.8%capacity retention over 1000 *** findings shed new insights to the fundamental mechanism of interfacial ion/electron synergy in stabilizing and enhancing fast-charging cathode materials.

关键词： High-voltage Fast-charging liCoO_(2) Interfacial ion-electron cooperation Local intercalation

Reoxidation of liquid steel and evolution of inclusions during protective atmosphere electroslag remelting of Ce-containing heat-resistant stainless steel

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Journal of Iron and Steel Research International 2024年第8期31卷 1923-1935页

作者： Yu Zhao Cheng-bin shi shijun wang Peng ren Jing li State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing(USTB)Beijing 100083China

The evolution of Ce-containing inclusions and its correlation with the reoxidation of liquid steel during protective atmosphere electroslag remelting(ESR)of heat-resistant steel were *** reoxidation of liquid steel took place during the ESR,resulting in the oxygen pickup from 0.0014 to 0.0053 wt.%.The inclusions in the consumable electrode,liquid metal pool and remelted ingot are Ce_(2)O_(2)S and Ce_(2)O,inclusions *** inclusions in the remelted ingot are originated from three ways:(I)the original inclusions from the electrode;(Il)the newly formed Ce_(2)O_(2)S and Ce_(2)O_(3) inclusions in the liquid metal pool by reoxidation remaining still in remelted ingot;(Ili)the newly generated Ce2O2S and Ce_(2)O_(3) inclusions during cooling and solidification of liquid *** relative proportions of Ce_(2)O_(3) inclusions in liquid metal pool and remelted ingot are 41% and 76.5%,*** inclusions ranging from 2 to 5μm in the remelted ingot take up 55%,followed by the inclusions smaller than 2μm(43%of total inclusions).The number proportion of the Ce_(2)0,inclusions in the liquid metal pool which were removed by floating up into slag is 1.96×10-5%.

关键词： Non-metallic inclusion Electroslag remelting Rare earth cerium Reoxidation Inclusion evolution

C2-phenyl-substituted benzimidazolium-based covalent organic framework as efficient catalyst for CO_(2) conversion without solvents,metals,and cocatalysts

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Science China Chemistry 2024年第2期67卷 551-557页

作者： Zhenzhen wu Jing wang lili liu Shang Guo Juan li Xianming Zhang Shanxi Institute for Functional Food Shanxi Agricultural UniversityTaiyuan030031China Institute of Crystalline Materials Shanxi UniversityTaiyuan030006China Key Laboratory of Interface Science and Engineering in Advanced Materials College of ChemistryTaiyuan University of TechnologyTaiyuan030024China

Covalent organic frameworks(COFs) are a potential platform for carbon dioxide(CO_(2)) conversion owing to their periodic permanent porosity,adjustable structure,and chemical *** good catalytic performance in CO_(2) conversion,collaborative multifunctions should be strategically integrated into the catalytic system design and *** this study,a four-in-one high-efficiency catalyst was synthesized and tested for CO_(2) cycloaddition to form cyclic *** obtained Tp-MPB-BrCOF had a high nitrogen content,which enhanced its CO_(2) affinity through substantial Lewis acid-base or dipole-quadrupole interactions;moreover,the acid(protons transferring from oxygen(–OH) to nitrogen(–NH)),hydrogen bond donor(hydroxyl group),and Br-(nucleophile group) served as three active sites,further improving the catalyst *** results provide a basis for designing efficient and stable CO_(2)-conversion catalysts.

关键词： covalent organic framework C2-phenyl-substituted benzimidazolium CO_(2)conversion four-in-one catalyst

Molding simulation of airfoil foam sandwich structure and interference optimization of foam-core

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Chinese Journal of Aeronautics 2024年第10期37卷 325-338页

作者： Qianying CEN Zeyang XING Qingyou wang lili li Zhigang wang Zhanjun wu ling liU School of Aerospace Engineering&Applied Mechanics Tongji UniversityShanghai 200092China AVIC Harbin Aircraft Industry Group Co.Ltd Harbin 150066China School of Aeronautics and Astronautics Dalian University of TechnologyDalian 116024China

During the Co-Cure Molding(CCM)of airfoil foam sandwich structure,it is challenging to avoid collapse of foam core at the trailing ***,an Equal Proportional Thickening(EPT)method is proposed to optimize the interference of polymethacrylimide(PMI)foam core during the CCM ***,based on some basic parameters of composite skin and foam core obtained by experiments or multi-scale simulations,a thermal-curing-mechanical coupling analysis for the CCM of foam sandwich structure is performed and the results show that the maximum stress within foam core occurs at the completion of mold-closing,which tends to decrease during the subsequent CCM ***,the foam core is thickened by traditional equidistant-thickening method,and the simulation reveals that the foam core at the trailing edge tends to collapse because of stress ***,if the foam core is thickened by the proposed EPT method,the mold-closing caused collapse at the trailing edge can be effectively avoided,and a thickening ratio range of 0.6%–2.0%is obtained,which is further proved by practical ***,the interference design scheme proposed can ensure the molding quality and effectively reduce the scrap of molded products.

关键词： Airfoil foam sandwich structure Polymethacrylimide(PMI)foam Interference Co-curing Molding simulation

Simplified quantitative analysis method and its application in the insitu synthesized copper-based azide chips

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Defence Technology（防务技术） 2024年第2期32卷 309-316页

作者： Jie ren Yunfeng li Mingyu li Xingyu wu Jiabao wang Qingxuan Zeng State Key Laboratory of Explosion and Technology Beijing Institute of TechnologyBeijing 100081China

Copper-based azide(Cu(N_(3))2 or CuN_(3),CA)chips synthesized by in-situ azide reaction and utilized in miniaturized explosive systems has become a hot research topic in recent ***,the advantages of in-situ synthesis method,including small size and low dosage,bring about difficulties in quantitative analysis and differences in ignition capabilities of CA *** aim of present work is to develop a simplified quantitative analysis method for accurate and safe analysis of components in CA chips to evaluate and investigate the corresponding ignition *** this work,Cu(N_(3))2 and CuN_(3)components in CA chips were separated through dissolution and distillation by utilizing the difference in solubility and corresponding content was obtained by measuring N_(3)-concentration through *** spectrophotometry method was optimized by studying influencing factors and the recovery rate of different separation methods was studied,ensuring the accuracy and reproducibility of test *** optimized method is linear in range from 1.0-25.0 mg/L,with a correlation coefficient R^(2)=0.9998,which meets the requirements of CA chips with a milligram-level content *** with the existing ICP method,component analysis results of CA chips obtained by spectrophotometry are closer to real component content in samples and have satisfactory ***,as its application in miniaturized explosive systems,the ignition ability of CA chips with different component contents for direct ink writing CL-20 and the corresponding mechanism was *** study provided a basis and idea for the design and performance evaluation of CA chips in miniaturized explosive systems.

关键词： Copper-based azide chips Spectrophotometry Separation method Quantitative analysis Ignition ability

Effects of anterior sciatic nerve acupuncture on lower limb paralysis after cerebral infarction:study protocol for a randomized controlled trial

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Journal of Traditional Chinese Medicine 2024年第1期44卷 205-211页

作者： li Menghan wang Yu RAN Dawei YANG Xinming DENG shizhe shi Lei MENG zhihong Department of Acupuncture First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300193China National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 300193China Graduate department Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Massage and Rehabilitation Second Affiliated Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300250China

Stroke is the main cause of disability in the middle and old ***,especially lower limb paralysis,often leads to the loss of self-care ability and a series of secondary *** main method to improve hemiplegic limb movement is exercise therapy,but there are still many patients with disabilities after rehabilitation *** one of the non-pharmacological therapies for stroke,acupuncture has been recognized to improve motor function in ***,we propose a new method,anterior sciatic nerve acupuncture,which can stimulate both the femoral nerve and the sciatic *** designed this study to determine the effect of this method on lower limb motor *** participants recruited with hemiplegia after cerebral infarction will be randomly assigned to the test group or control group in a 1:1 *** control group will receive Xingnao Kaiqiao acupuncture,and the test group will receive anterior sciatic nerve acupuncture on this *** participants will get acupuncture treatment once a day,6 times a week for 2 *** primary outcome is Fugl-Meyer Assessment of Lower Extremity and the secondary outcomes are Modified Ashworth Scale and Modified Barthel *** will be collected before treatment,1week after treatment,and 2 weeks after treatment,and then statistical analysis will be *** study can preliminarily verify the effect of anterior sciatic nerve acupuncture on improving lower limb motor function in patients with cerebral infarction,which may provide an alternative approach for clinical treatment of hemiplegia.

关键词： anterior sciatic nerve acupuncture paralysis cerebral infarction Xingnao Kaiqiao clinical protocols

Enhancing heavy gas capture in confined spaces through ventilation control technology

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Building Simulation 2024年第7期17卷 1161-1182页

作者： Tianqi wang Angui li yuanqing Ma Ying Zhang Haiguo Yin School of Building Services Science and Engineering Xi’an University of Architecture and TechnologyNo.13 Yanta RDXi’anShaanxi710055China

Gas leakage accidents occur frequently in confined spaces,and heavy gases with a relative density greater than 1.15 among hazardous gases and greenhouse gases are commonly stored in confined ***,atmospheric pollutant emission standards are becoming more stringent,and it is essential to remove heavy gas after accidents while reducing emissions to the *** study proposes using a heavy gas collection tank(HGCT)to safeguard the internal environment and minimize emissions to the *** capture efficiencies applicable to heavy-gas environments under different ventilation strategies are *** research analyzes the impact of the exhaust rate,leakage rate,density of heavy gas,and air supply modes on the indoor concentration *** results demonstrate that the mass flow rate of heavy gas into the exhaust is positively correlated with the exhaust rate,but the gas from the exhaust system contains more *** exhaust rate should be greater than four times the space volume per hour;otherwise,heavy gas above 1000 ppm accumulates to a height of 0.67 m at ground ***,attachment ventilation as make-up air helps to reduce upstream heavy gas accumulation and reduces the extension of heavy gas along the room *** an HGCT with floor slope and attachment ventilation achieves an efficiency of 96.28%.This study provides valuable insights and references for preventing hazardous heavy gas leakage.

关键词： confined gases otherwise

Design,modeling and experimental investigation of a novel solar sail with high area-to-mass ratios for efficient solar sailing

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Chinese Journal of Aeronautics 2024年第10期37卷 234-248页

作者： Zhongjing ren Chengyang li Ke wu Ziran wang Haipeng wang Peng YAN Key Laboratory of High-efficiency and Clean Mechanical Manufacture(Ministry of Education) School of Mechanical EngineeringShandong UniversityJinan 250061China China Manned Space Agency Beijing 100071China

Solar sailing is a promising propellant-free approach to propelling spacecraft in ***,the propelling efficiency of conventional solar sail spacecraft is limited by their areato-mass *** paper proposes a novel design of micro solar sails with area-to-mass ratios above 100 m2/kg for next-generation chip-scale *** thin films developed by Microelectromechanical Systems(MEMS)technologies were patterned into grid microstructures,and theoretical analysis of a sail prototype was *** electro-thermal and thermo-mechanical models of the solar sail in geospace were established by taking effects of Joule heating,solar radiation,and thermal re-emission into consideration,enabling rapid prediction of its threedimensional(3-D)reconfiguration from the as-released two-dimensional(2-D)*** of the ChipSail’s acceleration arising from the sail’s morphing was also analytically *** and characterization of the sail prototype made of multiple Al/Ni50Ti50 bilayer beams were ***-situ SEM imaging of the sail prototype in vacuum chamber witnessed an active and continuous 3-D reconfiguration under Joule heating,and over 90deformation was detected by applying a DC voltage of 0.078 *** and experimental work on the solar sail with at least 10 times higher area-to-mass ratios than conventional ones will lay a solid foundation for efficient solar sailing.

关键词： Solar sails Solar sailing High area-to-mass ratios Solar radiation pressure ChipSail