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Defence Technology（防务技术） 2024年第2期32卷 383-392页

作者： Li Ding Chong Wan Suhang Chen Zhao Qin Kangzhen Xu School of Chemical engineering/Xi'an Key Laboratory of Special Energy Materials Northwest UniversityXi'an710069China Xi’an Modern Chemistry research Institute Xi'an710065China

To enhance the catalytic activity of copper ferrite(CuFe_(2)O_(4))nanoparticle and promote its application as combustion catalyst,a low-cost silicon dioxide(SiO_(2))carrier was employed to construct a novel CuFe_(2)O_(4)/SiO_(2)binary composites via solvothermal *** phase structure,morphology and catalytic activity of CuFe_(2)O_(4)/SiO_(2)composites were studied firstly,and thermal decomposition,combustion and safety performance of ammonium perchlorate(AP)and 1,3,5-trinitroperhydro-1,3,5-triazine(RDX)with it affecting were then systematically *** results show that CuFe_(2)O_(4)/SiO_(2)composite can remarkably either advance the decomposition peak temperature of AP and RDX,or reduce the apparent activation energy at their main decomposition ***,the flame propagation rate of RDX was promoted by about 2.73 times with SiO_(2)content of 3 wt%,and safety property of energetic component was also improved greatly,in which depressing the electrostatic discharge sensitivity of pure RDX by about 1.89 *** addition,the effective range of SiO_(2)carrier content in the binary catalyst is found to be 3 to 5 wt%.Therefore,SiO_(2)opens a new insight on the design of combustion catalyst carrier and will promote the application of CuFe_(2)O_(4)catalyst in solid propellant.

关键词： Copper ferrite Silicon dioxide Combustion catalyst Thermal decomposition Laser ignition

Construction of wavelength-tunable DSE quinoline salt derivatives by regulating the hybridization form of the nitrogen atom and intramolecular torsion angle

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Chinese Chemical Letters 2024年第10期35卷 341-346页

作者： Kuan Deng Fei Yang Zhi-Qi Cheng Bi-Wen Ren Hua Liu Jiao Chen Meng-Yao She Le Yu Xiao-Gang Liu Hai-Tao Feng Jian-Li Li Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Shaanxi Key Laboratory for Carbon Neutral Technology College of Chemistry & Materials Science Northwest University Key Laboratory of Resource Biology and Biotechnology in Western China Ministry of Education Biomedicine Key Laboratory of Shaanxi Province Lab of Tissue Engineering the College of Life Sciences Faculty of Life Science & Medicine Northwest University Fluorescence research Group Singapore University of Technology and Design Baoji AIE research Center Shaanxi Key Laboratory of Phytochemistry College of Chemistry and Chemical Engineering Baoji University of Arts and Sciences

Dual-state emission(DSE) molecules displayed conspicuous fluorescent performance both in solid and solution states. However, the construction of DSE molecules and the regulation of their emission wavelengths remains a great challenge. Based on the structure-function relationship of quinolinonitrile-type fluorophores, this work proposed a feasible strategy for modulating their fluorescent properties into DSE via limiting the torsion angle between the quinoline ring and C=C bond in the range of 4.7° to 30°.Based on this strategy, 53 compounds were obtained which displayed tunable emission wavelengths from397 nm to 740 nm in solid-state and from 360 nm to 672 nm in solution. The feasibility of the strategy was supported by a series of theoretical calculations, optical characterizations, and crystal analysis, suggesting the compounds have great potential in imaging living cells and tissues with desired wavelengths.

关键词： Dual-state emission Fluorescence Fluorescent imaging Structure-function relationship Wavelength regulation

investigations of the mechanical response of dummy HTPB propellant grain under ultrahigh acceleration overload conditions using onboard flight-test measurements

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Defence Technology（防务技术） 2024年第2期32卷 473-484页

作者： Yiming Zhang Ningfei Wang Weihua Ma Ran Wang Long Bai Yi Wu School of Aerospace engineering Beijing Institute of TechnologyBeijing 100081China Beijing System design Institute of Electro-mechanic engineering Beijing 100854China Xi'an Changfeng research Institute of Mechanism and Electricity Xi'an 710065China

In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measurement system were *** projectiles containing dummy HTPB propellant grains were successfully recovered after the flight tests with an ultrahigh acceleration overload value of 8100 *** onboard-measured time-resolved axial displacement,contact stress and overload values were successfully obtained and *** compression tests of the dummy HTPB propellant used in the gunlaunched tests were carried out at low and intermediate strain rates to characterize the propellant's dynamic properties.A linear viscoelastic constitutive model was employed and applied in finite-element simulations of the projectile-launching *** the launch process,the dummy propellant grain exhibited large deformation due to the high acceleration overload,possibly leading to friction between the motor case and propellant *** calculated contact stress showed good agreement with the experimental results,though discrepancies in the overall displacement of the dummy propellant grain were *** dynamic mechanical response process of the dummy propellant grain was analysed in *** results can be used to estimate the structural integrity of the analysed dummy propellant grain during the gun-launch process.

关键词： Gun-launched flight test Dummy HTPB propellant Onboard measurements Utrahigh overload Mechanical response

A novel fused bi-macrocyclic host for sensitive detection of Cr_(2)O_(7)^(2-)based on enrichment effect

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Chinese Chemical Letters 2024年第7期35卷 291-295页

作者： Ting-Ting Huang Jin-Fa Chen Juan Liu Tai-Bao Wei Hong Yao Bingbing Shi Qi Lin Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China Key Laboratory of Environment-Friendly Composite Materials of the State Ethnic Affairs Commission Gansu Provincial Biomass Function Composites Engineering Research CenterCollege of Chemical EngineeringNorthwest Minzu University(Northwest University for Nationalities)Lanzhou 730000China

Improving the highly selective and sensitive binding of chemosensor to target guest is always very *** order to solve this issue,herein,the enrichment effect was introduced into the design of chemosensor molecule.A novel bi-fused-macrocyclic host molecule BPN1 was synthesized by bridging a pillar[5]arene and a naphthalene diimide(NDI)group through hydrogen-bond-rich *** the BPN1,the naphthalimide side ring is outside the cavity of the pillar[5]*** addition,Cr(VI)greatly threat human health and the environment due to its severe toxicity,and it is very important to develop effective chemosensor for sensitive and selective detection of Cr_(2)O_(7)^(2-)or its ion *** this paper,the novel bi-fused-macrocyclic host molecule BPN1 can recognize Cr_(2)O_(7)^(2-)with high selectivity and *** mechanism of BPN1 recognition of Cr_(2)O_(7)^(2-)was studied through experiments and density functional theory(DFT),the results show that BPN1 could supply enrichment effect to bind Cr_(2)O_(7)^(2-)through multiple weak interactions such as hydrogen bonds and anion-π,and achieve highly sensitive and selective detection of Cr_(2)O_(7)^(2-).It is a significant and feasible strategy for improve high selectivity and sensitivity of host to specific objects by using the enrichment effect of fused bi-macrocyclic.

关键词： Pillararene Bi-macrocyclic Detection of Cr_(2)O_(7)^(2−) DFT The enrichment effect

Uncertainty quantification of mechanism motion based on coupled mechanism—motor dynamic model for ammunition delivery system

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Defence Technology（防务技术） 2024年第3期33卷 125-133页

作者： Jinsong Tang Linfang Qian Longmiao Chen Guangsong Chen Mingming Wang Guangzu Zhou Nanjing University of Science and Technology Nanjing 210094China northwest Institute of Mechanical and Electrical engineering Xianyang 712099China

In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this *** main contribution is to propose a novel mechanism-motor coupling dynamic modeling method,in which the relationship between mechanism motion and motor rotation is established according to the geometric coordination of the *** advantages of this include establishing intuitive coupling between the mechanism and motor,facilitating the discussion for the influence of both mechanical and electrical parameters on the mechanism,and enabling dynamic simulation with controller to take the randomness of the electric load into *** simulation considering feedback control of ammunition delivery system is carried out,and the feasibility of the model is verified *** on probability density evolution theory,we comprehensively discuss the effects of system parameters on mechanism motion from the perspective of uncertainty *** work can not only provide guidance for engineering design of ammunition delivery mechanism,but also provide theoretical support for modeling and uncertainty quantification research of mechatronics system.

关键词： Ammunition delivery system Electromechanical coupling dynamics Uncertainty quantification Generalized probability density evolution

Command filtered integrated estimation guidance and control for strapdown missiles with circular field of view

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Defence Technology（防务技术） 2024年第5期35卷 211-221页

作者： Wei Wang Jiaqi Liu Shiyao Lin Baokui Geng Zhongjiao Shi School of Aerospace engineering Beijing Institute of TechnologyBeijing 10081China China research and Development Academy of Machinery Equipment Beijing 100089China northwest Industries Group CO. Ltd.Xi'an 710043China

In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown *** threedimensional integrated estimation guidance and control nonlinear model with limited actuator deflection angle is established considering the seeker's FOV *** boundary time-varying integral barrier Lyapunov function(IBLF)is employed in backstepping design to constrain the body line-of-sight(BLOS)in IEGC system to fit a circular ***,the nonlinear adaptive controller is designed to estimate the changing aerodynamic *** generalized extended state observer(GESO)is designed to estimate the acceleration of the maneuvering targets and the unmatched time-varying disturbances for improving tracking ***,the command filters are used to solve the"differential expansion"problem during the backstepping *** Lyapunov theory is used to prove the stability of the overall closed-loop IEGC ***,the simulation results validate the integrated system's effectiveness,achieving high accuracy strikes against maneuvering targets.

关键词： Integrated estimation guidance and control Circular field-of-view Time-varying integral barrier Lyapunov function Command filtered backstepping control Nonlinear adaptive control Extended state observer

design and optimization of torsion harvester of Lycium barbarum L.

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International Journal of Agricultural and Biological engineering 2024年第4期17卷 109-115页

作者： Qingyu Chen Shixia Zhang Naishuo Wei Puhang Li Guangrui Hu Jun Chen Yu Chen College of Mechanical and Electronic engineering Northwest A&F UniversityYangling 712100ShaanxiChina

The production of Lycium barbarum *** a labor-intensive *** manual harvests are required during the harvesting season,which contributes to the high harvesting *** cultivation conditions of *** were investigated to increase efficiency and mitigate harvesting damage.A torsion harvester was designed according to the characteristic of infinite inflorescence and the distribution of detachment force,and the kinematics model of the harvester was *** vibration responses of ripe and unripe fruit were obtained through ADAMS simulation of the branch model,and the influencing factors and value range of the torsion harvester were also *** mathematical models of ripe fruit harvesting rate,unripe fruit harvesting rate,ripe fruit damage rate and torsion angle,vibration rods distance,and vibration frequency were established by the Box-Behnken *** influences of various factors on ripe fruit harvesting rate,unripe fruit harvesting rate,and ripe fruit damage rate were analyzed,and the best parameter combination was obtained:torsion angle 73.66°,vibration rods distance 35.51 mm and vibration frequency 19.12 *** experiment showed that the harvesting rate of ripe fruit is 95.67%,the harvesting rate of unripe fruit is 4.68%,and the damage rate of ripe fruit is 3.70%.The research results can promote the mechanization process of *** harvest,and provide a reference for vibration harvest of berries.

关键词： L.barbarum vibrating torsion response surface method parameters optimization ADAMS RSM

Response of Bacterial Community and Enzyme Activity of Greenhouse Tomato under Different Irrigation Systems

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1543-1568页

作者： Haijian Yang Mingzhi Zhang Na Xiao Yuan Li Faculty of engineering Huanghe Science and Technology UniversityZhengzhou450063China northwest Land and Resources research Center Shaanxi Normal UniversityXi’an710119China

The micro-sprinkler irrigation mulched(MSM)has been suggested as a novel water-saving approach in con-trolled environment ***,the effects of microbial community structure and enzyme activity in the rhizosphere soil on crop growth under MSM remain *** study conducted a randomized experimen-tal design using greenhouse tomatoes to investigate changes in bacterial community structure and enzyme activity in rhizosphere soil under different irrigation frequencies(F)and amounts(I)of ***ﬁndings revealed that with the increase of F or I,The total count of soil bacteria in tomatoesﬁrst rose and then fell in terms of Opera-tional Taxonomic Units(OTUs)classiﬁ*** to other F,the most abundance of nitrogen and phos-phorus metabolism genes and enzyme activities were observed with a 5-day ***,the diversity of soil bacterial community structure initially rose before eventually declining with the increase of the *** 1.00 Epan(cumulative evaporation of a 20 cm standard pan)under MSM helped boost the abundance of nitrogen and phosphorus metabolism functional genes in soil bacteria,ensuring higher enzyme activities related to nitro-gen,carbon,and phosphorus metabolism in the rhizosphere soil of ***’yield initially rose before eventually declining with the increase in F or I,whereas I had a more signiﬁcant effect on yield.A 1.00%increase in I yielded a minimum of 39.24%increase in tomato *** study showed a positive correlation between soil bacterial community,soil enzyme activity,and greenhouse tomato yield under *** the results comprehensively,the combined irrigation mode of F of 5 d and I of 1.00 Epan was recommended for greenhouse tomatoes under *** conclusion provides theoretical support for water-saving practices and yield improve-ment in facility agriculture,especially tomato cultivation.

关键词： Greenhouse tomato yield bacterial community enzyme activity model

Exploring mechanism of hidden,steep obliquely inclined bedding landslides using a 3DEC model:A case study of the Shanyang landslide in Shaanxi Province,China

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China Geology 2024年第2期7卷 303-314,I0001-I0003页

作者： Jia-yun Wang Zi-long Wu Xiao-ya Shi Long-wei Yang Rui-ping Liu Na Lu Xi’an Center of China Geological Survey/northwest China Center for Geoscience Innovation Xi’an 710119China Xi’an University of Science and Technology Xi’an 710054China Wuhan design&research Institute Co. Ltd.of China Coal Technology&Engineering GroupWuhan 430064China

Catastrophic geological disasters frequently occur on slopes with obliquely inclined bedding structures(also referred to as obliquely inclined bedding slopes),where the apparent dip sliding is not readily *** phenomenon has become a focal point in landslide ***,there is a lack of studies on the failure modes and mechanisms of hidden,steep obliquely inclined bedding *** study investigated the Shanyang landslide in Shaanxi Province,*** field investigations,laboratory tests of geotechnical parameters,and the 3DEC software,this study developed a numerical model of the landslide to analyze the failure process of such *** findings indicate that the Shanyang landslide primarily crept along a weak interlayer under the action of *** landslide,initially following a dip angle with the support of a stable inclined rock mass,shifted direction under the influence of argillization in the weak interlayer,moving towards the apparent dip *** slide resistance effect of the karstic dissolution zone was increasingly significant during this process,with lateral friction being the primary resistance force.A reduction in the lateral friction due to karstic dissolution made the apparent dip sliding characteristics of the Shanyang landslide more ***,deformations such as bending and uplift at the slope’s foot suggest that the main slide resistance shifts from lateral friction within the karstic dissolution zone to the slope foot’s resistance force,leading to the eventual buckling failure of the *** study unveils a novel failure mode of apparent dip creep-buckling in the Shanyang landslide,highlighting the critical role of lateral friction from the karstic dissolution zone in its failure *** insights offer a valuable reference for mitigating risks and preventing disasters related to obliquely inclined bedding landslides.

关键词： Landslide Steep obliquely inclined bedding slope Failure mode Failure mechanism Apparent dip creep-buckling Lateral friction 3DEC model Landslide numerical model Geological hazards survey engineering

Experimental and numerical interpretation on composite foundation consisting of soil-cement column within warm and ice-rich frozen soil

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Journal of Mountain Science 2024年第1期21卷 313-321页

作者： WANG Honglei ZHANG Jianming WEI Shoucai SUN Zhizhong ZHANG Hu School of Civil engineering Hebei University of EngineeringHandan 056038China State Key Laboratory of Frozen Soil engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Second Geological Brigade Bureau of Geology and Mineral Resources Exploration and DevelopmentLhasa 850000China Da Xing’anling Observation and research Station of Frozen Ground engineering and Environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJiagedaqi 165100China School of Civil engineering Northeast Forestry UniversityHarbin 150040China

Affected by climate warming and anthropogenic disturbances, the thermo-mechanical stability of warm and ice-rich frozen ground along the Qinghai-Tibet engineering corridor(QTEC) is continuously decreased, which may delay the construction of major projects in the future. In this study, based on chemical stabilization of warm and icerich frozen ground, the soil-cement column(SCC) for ground improvement was recommended to reinforce the foundations in warm and ice-rich permafrost regions. To explore the validity of countermeasures mentioned above, both the original foundation and the composite foundation consisting of SCC with soil temperature of -1.0℃ were prepared in the laboratory, and then the plate loading tests were carried out. The laboratory investigations indicated that the bearing capacity of composite foundation consisting of SCC was higher than that of original foundation, and the total deformation of original foundation was greater than that of composite foundation, meaning that overall stability of foundation with warm and ice-rich frozen soil can be improved by SCC installation. Meanwhile, a numerical model considering the interface interaction between frozen soil and SCC was established for interpretating the bearing mechanism of composite foundation. The numerical investigations revealed that the SCC within composite foundation was responsible for the more applied load, and the applied load can be delivered to deeper zone in depth due to the SCC installation, which was favorable for improving the bearing characteristic of composite foundation. The investigations provide the valuable guideline for the choice of engineering supporting techniques to major projects within the QTEC.

关键词： Chemical stabilization Ground improvement Composite foundation Frozen soil engineering Qinghai-Tibet engineering corridor