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Defence Technology（防务技术） 2024年第7期37卷 1-13页

作者： guangbo Xu Bingting zha Hailu Yuan zhen zheng He zha.g Ministerial Key Laboratory of ZNDY Nanjing University of Science and TechnologyNanjing 210094China Science and Technology on Electromechanical Dynamic Control Laboratory Beijing 100081China Shanghai Radio Equipment Research Institute Shanghai 201109China

The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser *** overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering *** enhances the algorithm loading capability of the *** order to address the problem of insufficient filtering capacity in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)*** also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy and anti-interference capability of the ***,experiments are conducted with varying signal-to-noise ratios of the original underwater target echo *** experimental results show that the average signal-to-noise ratio before and after filtering can be improved by more than31 d B,with an increase of up to 76%in extreme detection distance.

关键词： Laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm

NUMERICAL ANALYSIS OF THE UNSTEADY FORCE IN INSECT FORWARD FLIgHT

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Journal of Hydrodynamics 2006年第2期18卷 143-147页

作者： zha Xiong-quan LU Xi-yun YIN Xie-zhen Department of Mechanics and Mechanical Engineering University of Science and Technology of China Hefei 230026 China

The objective of this study is to get into physical insights to the unsteady force and the relevant mechanisms in forward flight of insects. Unsteady force in the forward flight was studied, based on a virtual model problem of a foil with oscillating translation and rotation in a uniform flow, by solving the two-dimensional incompressible Navier-Stokes equations with a finite element method. The effects of typical parameters, including the advance ratio, the inclined angle of stroke plane, the stroke amplitude, and the amplitude of pitching angle of attack, on the forces and the flow structures were analyzed.

关键词： unsteady flow vortex dynamics thrust and lift,flapping motion biomechanics

Origin of Felsic Microgranitoid Enclaves in granite in zha.gjiakou District,China:Implication for Process and Lifespan of granitic Magma Chambers

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Acta geologica Sinica(English Edition) 2024年第6期98卷 1461-1478页

作者： WANg Dazhao LIU Yuhang LENg Chengbiao zhen Shimin LIU Jiajun zha Zhongjian National Key Laboratory of Uranium Resources Exploration-Mining and Nuclear Remote Sensing Nanchang 330013China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Development and Research Center of China geological Survey Beijing 100037China Technical guidance Center for Mineral Resources Exploration Ministry of Natural ResourcesBeijing 100083China State Key Laboratory of geological Processes and Mineral Resources China University of Geosciences(Beijing)Beijing 100083China School of Earth Science and Resources China University of Geosciences(Beijing)Beijing 100083China Institute of geological Surveying and Mapping Technology of Anhui Province Hefei 230022China

Sparse felsic microgranitoid enclaves(FMEs)in the Shangshuiquan granite of the zha.gjiakou district,the north margin of the North China Craton,are fine-grained,dark-colored and exhibit subangular to subspherical *** share similar mineral assemblages,chemical compositions,and zircon Hf isotope compositions to the host *** zircon U-Pb geochronology reveals that the FMEs crystallized at 156-153 Ma,while the Shangshuiquan granite formed at ca.146 *** FEMs are,therefore,10 to 7 Ma older than the host *** with petrological evidence,we suggest that the FMEs are fragments of rapidly crystalized magmas,which were captured by the younger Shangshuiquan *** of the FMEs and Shangshuiquan granite originated from the same *** Shangshuiquan granite is the result of small batches of magma being built up incrementally,and the FMEs belong to the earlier batches of *** lifespan of the Shangshuiquan magma reservoir exceeds 10 *** derived from cogenetic fragments have the potential to offer critical information about the formation process and timescale of granitic plutons.

关键词： felsic microgranitoid enclaves autoliths chilled margins lifespan of magma chamber north margin of the North China Craton

Transient Stability Analysis of Converter-based Islanded Microgrids Based on Iterative Equal Area Criterion Considering Reactive Power Loop Dynamics and Varying Damping

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1170-1182页

作者： Xilin Li Jingyi zha.g zhen Tian Xiaoming zha Wei Wang Meng Huang Chong Shao Hubei Key Laboratory of Power Equipment&System Security for Integrated Energy School of Electrical Engineering and AutomationWuhan UniversityWuhanChina NARI Technology Co. Ltd.NanjingChina State grid gansu Electric Power Company LanzhouChina

With the rapid increase in the installed capacity of renewable energy in modern power systems,the stable operation of power systems with considerable power electronic equipment requires further *** converter-based islanded microgrid(CIM)systems equipped with grid-following(gFL)and grid-forming(gFM)voltage-source converters(VSCs),it is challenging to maintain stability due to the mutual coupling effects between different VSCs and the loss of voltage and frequency support from the power *** previous studies,quantitative transient stability analysis was primarily used to assess the active power loop of ***,frequency and voltage dynamics are found to be strongly coupled,which strongly affects the estimation result of stability *** addition,the vary-ing damping terms have not been fully *** bridge these gaps,this paper investigates the transient stability of CIM consid-ering reactive power loop dynamics and varying ***,an accuracy-enhanced nonlinear model of the CIM is derived based on the effects of reactive power loop and post-disturbance frequency jump *** these effects will eliminates the risk of *** reactive power loop dynamics make the model coefficients be no longer constant and thus vary with the power *** evaluate quantitatively the effects of re-active power loop and varying damping on the transient stability of CIM,an iterative criterion based on the equal area criterion theory is *** addition,the effects of parameters on the stable boundary of power system are analyzed,and the dynamic interaction mechanisms are *** and experiment results verify the merits of the proposed method.

关键词： Transient stability converter iterative criterion reactive power loop post-disturbance frequency jump

A green and efficient access to aryl nitriles via an electrochemical anodic oxidation

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Chinese Chemical Letters 2014年第8期25卷 1112-1114页

作者： Jia-Qian Ye zhen-Lei zha.g zheng-gen zha Zhi-Yong Wang Hefei National Laboratory for Physical Sciences at Microscale CAS Key Laboratory of Soft Matter Chemistry & Collaborative Innovation Center of Suzhou Nano Science and Technology University of Science and Technology of China

The nitrile functionality is a key building block in synthetic chemistry, and has wide applications in pharmaceuticals. However, traditional methodologies for the synthesis of nitriles are limited to harsh reaction conditions. Herein, we report a new and efficient access to aryl nitriles by an electrochemical synthesis. Compared with the conventional synthetic methods, this electrochemical synthesis is more environmentally friendly and easier to handle.

关键词： Eletrochemistry Anodic oxidation Aryl nitrile

Integrated intrusion detection model based on artificial immune

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 83-90页

作者： zha.g Ling BAI Zhong-ying LU Yun-long zha Ya-xing LI zhen-wen School of Computer Science Beijing University of Posts and Telecommunications zhengzhou University of Light Industry

The author puts forward an integrated intrusion detection （ID） model based on artificial immune （IIDAI）, a vaccination strategy based on the significance degree of genes and a method to generate initial memory antibodies with rough set （RS）. IIDAI integrates two kinds of intrusion detection mode： misuse detection and anonymous detection. Misuse detection and anonymous detection are applied to detect the known and the unknown attacks, respectively. On the basis of IIDAI model, an ID algorithm is presented. Simulation shows that the IIDAI has better performance than traditional ID methods in feasibility and effectiveness. It is very prone to achieve a higher convergence rate by using the vaccination strategy. Moreover, RS can remove the redundancy attributes and increase the detection speed. It can also increase detection rate by applying the integrated method.

关键词： ID RS artificial immune vaccination

Composition design of superhigh strength maraging stainless steels using a cluster model

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Progress in Natural Science:Materials International 2014年第1期24卷 35-41页

作者： zhen Li Ruiqian zha.g Qianfeng zha Yingmin Wang Jianbing Qiang Chuang Dong School of Mechanical Engineering Dalian University of Technology Science and Technology on Reactor Fuel and Materials Laboratory Nuclear Power Institute of China Key Laboratory of Materials Modification Dalian University of TechnologyMinistry of Education

The composition characteristics of maraging stainless steels were studied in the present work investigation using a cluster-plus-glue-atom model. The least solubility limit of high-temperature austenite to form martensite in basic Fe–Ni–Cr corresponds to the cluster formula [NiFe12]Cr3,where NiFe12is a cuboctahedron centered by Ni and surrounded by 12 Fe atoms in FCC structure and Cr serves as glue atoms. A cluster formula [NiFe12](Cr2Ni) with surplus Ni was then determined to ensure the second phase(Ni3M) precipitation,based on which new multicomponent alloys [(Ni,Cu)16Fe192](Cr32(Ni,Mo,Ti,Nb,Al,V)16) were designed. These alloys were prepared by copper mould suction casting method,then solid-solution treated at 1273 K for 1 h followed by water-quenching,and finally aged at 783 K for 3 h. The experimental results showed that the multi-element alloying results in Ni3M precipitation on the martensite,which enhances the strengths of alloys sharply after ageing treatment. Among them,the aged [(Cu4Ni12)Fe192](Cr32(Ni8.5Mo2Ti2Nb0.5Al1V1)) alloy(Fe74.91Ni8.82Cr11.62Mo1.34Ti0.67Nb0.32Al0.19V0.36Cu1.78wt%) has higher tensile strengths with YS?1456 MPa and UTS?1494 MPa. It also exhibits good corrosion-resistance in 3.5 wt% NaCl solution.

关键词： Maraging stainless steels Composition design Cluster structure model Super-high strength

Minimally invasive surgery vs laparotomy in patients with colon cancer residing in high-altitude areas

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World Journal of Clinical Cases 2021年第35期9卷 10919-10926页

作者： Duo-Ji Suo Lang Yang-zhen Ci Ren zha-Xi Bian Ba Department of general Surgery People’s Hospital of Tibet Autonomous RegionLasa 850000Tibet Autonomous RegionChina Department of Internal Medicine The Tibet Autonomous Region Centers for Disease Control and PreventionLasa 850000Tibet Autonomous RegionChina

BACKgROUND Colon cancer is associated with a higher incidence among residents in highaltitude *** environment at high altitudes inhibits the phagocytic and oxygen-dependent killing function of phagocytes,thereby increasing the inflammatory factors,inhibiting the body’s innate immunity and increasing the risk of colon *** To examine the effect of minimally invasive surgery vs laparotomy in patients with colon cancer residing in high-altitude *** Ninety-two patients with colon cancer in our hospital from January 2019 to February 2021 were selected and divided into the minimally invasive surgery and laparotomy groups using the random number table method,with 46 patients in each *** invasive surgery was performed in the minimally invasive group and laparotomy in the laparotomy *** conditions,inflammatory index pre-and post-surgery,immune function index and complication probability were *** Operative duration was significantly longer and intraoperative blood loss and recovery time of gastrointestinal function were significantly less(all Pgroup than in the laparotomy *** number of lymph nodes dissected was not significantly *** surgery,there were no significant differences in serum C-reactive protein,interleukin-6 and tumor necrosis factor-αlevels between the groups,whereas after surgery,the levels were significantly higher in the minimally invasive group(26.98±6.91 mg/L,146.38±11.23 ng/mL and 83.51±8.69 pg/mL vs 41.15±8.39 mg/L,186.79±15.36 ng/mL and 110.65±12.84 pg/mL,respectively,Pgery,there were no significant differences in CD3+,CD4+and CD4+/CD8+levels between the groups,whereas after surgery,the levels decreased in both groups,being significantly higher in the minimally invasive group(55.61%±4.39%,35.45%±3.67%and 1.30±0.35 vs 49.68%±5.33%,31.21%±3.25%and 1.13±0.30,respectively,Pgnificant

关键词： Minimally invasive surgery Laparotomy High-altitude area Colon cancer Surgical trauma Immune dysfunction

Electrosynthesis of oxadiazoles from benzoylhydrazines

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Chinese Chemical Letters 2013年第9期24卷 780-782页

作者： Huan-Yue Ma zheng-gen zha zhen-Lei zha.g Li Meng Zhi-Yong Wang Hefei National Laboratory for Physical Sciences at Microscale CAS Key Laboratory of Soft Matter Chemistry and Department of Chemistry Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics University of Science and Technology of China

A highly efficient conformation from facile benzoylhydrazines was developed under electrochemical condition. A variety of oxadiazoles were obtained with good yields by virtue of this new method.

关键词： Oxadiazoles Electrochemical reactions Steric effect

A corrosion-resistant and age-hardenable Mg-Al-Mn-Ca-Ce dilute alloy with fine-grained structure processed by controlled rolling

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Journal of Materials Science & Technology 2023年第32期163卷 223-236页

作者： Jia-Sheng Li Mei-Xuan Li zhen-Ming Hua Yuan-Ting Mo Kai guan Min zha Yipeng gao Hui-Yuan Wang Key Laboratory of Automobile Materials of Ministry of Education&School of Materials Science and Engineering Nanling CampusJilin UniversityChangchun 130025China State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130012China International Center of Future Science Jilin UniversityChangchun 130012China

Low strength and poor corrosion resistance are two long-standing bottlenecks with dilute Mg ***,we report that the corrosion resistance of Mg-0.6Al-0.5Mn-0.2Ca(wt.%)alloy sheet can be significantly improved by micro-alloying with 0.3 wt.%Ce,and the strength can be considerably augmented after aging *** optimization of strength,ductility,and corrosion resistance is difficult due to the inherent trade-off in Mg ***,our aged Mg-0.6Al-0.5Mn-0.2Ca-0.3Ce alloy features with yield strength(YS)of∼194 MPa,ultimate tensile strength(UTS)of∼265 MPa,elongation to failure(EF)of∼17.2%,and corrosion rate(CR)of 2.2 mm y^(−1),the combination of which exhibits competitive advantage over other comparative dilute Mg *** is found that Ce addition decreases the activity of cathodic phases,inhibits detrimental effects of Fe impurities,and forms a protective Ce-containing surface *** high strength stems from the precipitation of ordered guinier-Preston(g.P.)zones dispersed in uniform fine grains with an average grain size of∼8.2μ*** atomic-scale *** result in a noticeable age hardening response but do not act as crack initiation and propagation site,so our alloy also performs satisfactory *** work sheds light on the design and fabrication of strong,ductile,and corrosion-resistant dilute magnesium alloys to be used in electronic products and automotive bodies.

关键词： Magnesium alloy Micro-alloying Aging g.P.zones Mechanical property Corrosion