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Adaptive allocation strategy for cooperatively jamming netted radar system based on improved cuckoo search algorithm

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Defence Technology（防务技术） 2023年第6期24卷 285-297页

作者： De-jiang Lu Xing Wang xiao-tian Wu You Chen Aviation Engineering School Air Force Engineering UniversityXi'an710038China

The jamming resource allocation problem of the aircraft formation cooperatively jamming netted radar system is *** adaptive allocation strategy based on dynamic adaptive discrete cuckoo search algorithm(DADCS)is proposed,whose core is to adjust allocation scheme of limited jamming resource of aircraft formation in real time to maintain the best jamming effectiveness against netted radar ***,considering the information fusion rules and different working modes of the netted radar system,a two-factor jamming effectiveness evaluation function is constructed,detection probability and aiming probability are adopted to characterize jamming effectiveness against netted radar system in searching and tracking mode,*** a nonconvex optimization model for cooperatively jamming netted radar system is ***,a dynamic adaptive discrete cuckoo search algorithm(DADCS)is constructed by improving path update strategies and introducing a global learning mechanism,and a three-step solution method is proposed *** results are provided to demonstrate the advantages of the proposed optimization strategy and the effectiveness of the improved algorithm.

关键词： Cuckoo search algorithm Netted radar system Radar countermeasures Resource allocation Information fusion

Effects of adverse pressure gradient on Reynolds stresses inturbulent boundary layers

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航空动力学报 2017年第2期32卷 463-469页

作者： LUO xiao-tian ZHANG Ce MA Wei TENG Jin-fang School of Aeronautics and Astronautics Shanghai Jiao Tong University

The effects of adverse pressure gradient(APG)on Reynolds stresses in turbulent boundary layers(TBLs)with APG were *** difficulty of this work was attributable to the Reynolds stresses in TBLs with APG under two combined effects,i.e.:effect of upstream flow and effect of *** effect of upstream flow is an inherent effect no matter pressure gradient exists or *** individual effect was analyzed from absolute developments of Reynolds stresses in TBLs with zero pressure gradient(ZPG)*** of APG was then analyzed from absolute developments of Reynolds stresses in TBLs with *** showed that,for absolute development of mean streamwise Reynolds stresses,APG accelerated its development in TBL with ZPG;for absolute development of mean normal or shear Reynolds stresses,APG increased their magnitude in the outer part,and decreased their extent of large value region.

关键词： turbulent boundary layer adverse pressure gradient zero pressure gradient Reynolds stresses flat plate

Influence of rare earth element terbium doping on microstructure and magnetostrictive properties of Fe_(81)Al_(19) alloy

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Journal of Rare Earths 2022年第3期40卷 451-456,I0004页

作者： Rui Wang xiao tian Zhanquan Yao Xuan Zhao Hongbo Hao Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials School of Physics and Electronic InformationInner Mongolia Normal UniversityHohhot 010022China School of Water Conservancy and Civil Engineering Inner Mongolia Agricultural UniversityHohhot 010018China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030China

Fe_(81)Al_(19)Tb_(x)(x=0,0.05,0.1,0.2,0.3,0.4)alloys were prepared by a non-consumable vacuum arc melting technique under an inert argon gas *** microstructures of the alloys were studied by X-ray diffraction(XRD)and scanning electron microscopy combined with an energy dispersive spectroscopy(SEM/EDS).The magnetic properties and magnetostriction coefficients of the alloys were measured by a vibrating sample magnetometer(VSM)and adifferential resistive strain sensor,*** results show that the Fe_(81)Al_(19)alloy consists of a single A2 phase with bcc structure,whereas the Tb doped Fe_(81)Al_(19)alloys are composed of the A2 phase and a small amount of rare earth-rich *** doping of the rare earth element Tb makes the Fe_(81)Al_(19)alloy preferentially oriented along with thecrystal *** the increase of Tb content,the magnetostriction coefficient of the alloy first increases and then *** x=0.1,the magnetostriction coefficient reaches the maximum,which is 146×10^(−6).Compared with the as-cast Fe_(81)Al_(19)alloy(27×10^(−6)),it increases by 441%.The enhanced magnetostrictive properties are mainly attributed to the preferred orientation alongof A2 phase of the Tb doped Fe_(81)Al_(19)alloys and lattice distortion caused by the small amount of rare earth atoms entering the Fe-Al alloy lattice.

关键词： Fe-Al alloy Magnetostriction Lattice distortion Preferred orientation Rare earths

Improvement of Low-Frequency Sound Field Obtained by an Optimized Boundary

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Journal of China University of Mining and Technology 2006年第3期16卷 367-370,375页

作者： JING Lu ZHU xiao-tian School of Art and Design China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Architecture ＆ Civil Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

An approach based on the finite element analysis was introduced to improve low-frequency sound field. The optimized scatters on the wall redistribute the modes of the room and provide effective diffusion of sound field. The obtained through a 1：5 scaled set up. The results show that the optimized treatment has a positive effect on sound field and the improvement is obvious.

关键词： low-frequency sound field finite element analysis optimization scatters

Enhancing electrochemical performance of ultrasmall Fe_(2)O_(3)-embedded carbon nanotubes via combusting-induced high-valence dopants

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Journal of Materials Science & Technology 2023年第3期134卷 142-150页

作者： Yuan Wang Tao Zhang Jianfei xiao xiaobao tian Shaojun Yuan Low-carbon Technology and Chemical Reaction Engineering Lab College of Chemical EngineeringSichuan UniversityChengdu 610065China College of Architecture and Environment Sichuan UniversityChengdu 610065China

Doping is a reasonable solution to improve the electronic structure and surface properties of ***,we propose a rapid and simple methodology,flame synthesis,as an effective preparation strategy for incorporating high-valence metal ions(Ti^(4+),Sn^(4+),and Zr^(4+))into ultrasmall Fe_(2)O_(3)on carbon nanotube support(i.e.,M-FeO-CNT).The resulting materials exhibit not only a boosted Na+adsorption as shown by density functional theory(DFT)calculations,but also display an increased oxygen *** electrochemical activity and charge transfer efficiency of Fe 2 O 3 can be improved by reasonably sub-stituting Fe 3+with Ti^(4+),Sn^(4+),and Zr^(4+).The electrochemical investigation of Ti-doped Fe 2 O 3(Ti-FeO-CNT)electrode demonstrates a splendid specific capacitance of 1.25 F cm^(−2)at 1 mA cm^(−2)in 1 M Na_(2)SO_(4).This is significantly higher as compared to the capacitance of 0.48 F cm^(−2).Flexible solid-state asymmetric su-percapacitor Ti-FeO-CNT//MnO_(2)is verified with operating voltage of 2.0 V and stability over 3000 cycles,and delivers a high energy density of 2.14 mWh cm^(−3)at power density of 25 mW cm−*** flame synthesis is expected to be widely applicable for the preparation of high-valence metal ions doped nanosized Fe_(2)O_(3)functionalized materials,thus opening up new avenues for energy and catalysis research.

关键词： Ultrasmall Fe_(2)O_(3)nanoparticles Doping Flame synthesis Flexible supercapacitor DFT calculations

Promoting performance of lithium-sulfur battery via in situ sulfur reduced graphite oxide coating

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Rare Metals 2021年第2期40卷 417-424页

作者： Yuan Li xiao-tian Guo Song-Tao Zhang Huan Pang Department of Pharmacy Jiangsu Food and Pharmaceutical Science CollegeHuai’an223003China School of Chemistry and Chemical Engineering Guangling CollegeYangzhou UniversityYangzhou225000China

Activated graphene/sulfur structure sheathed in a flexible graphene layer is presented as the cathode material of lithium-sulfur *** surface coating graphite oxide sheets are reduced by a one-step in situ sulfur reduction method under vacuum at 600℃without any additional *** high reduction degree of in situ sulfur reduced graphite oxide(RGO)coating layer will facilitate the rapid charge transfer at high current *** flexible encapsulated RGO structure will retard the diffusion of polysulfides and adjust the volume change of sulfur in *** a result,the electrochemical evaluation of the RGO-activated graphene(AG)/S electrode demonstrates superior capacity,cycling and rate *** RGO-AG/S electrode with 60 wt%sulfur loading achieves a stable cyclability over 2000 galvanostatic charge/discharge process(capacity-fade rate of only 0.03%per cycle at1600 mA·g^(-1)).The average Coulombic efficiency remains at~96%with no electrolyte additives(such as LiNO_(3)).The outstanding property of RGO-AG/S electrode is attributed to the distinctive in situ sulfur RGOcoated hierarchical texture.

关键词： Lithium-sulfur battery Surface coating In situ Activated graphene Long-term stability

Severe bleeding after operation of preauricular fistula:A case report

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World Journal of Clinical Cases 2021年第29期9卷 8932-8937页

作者： Chun-Hui tian xiao-Juan Chen Department of Otolaryngology—Head and Neck Surgery Suzhou Hospital of Anhui Medical UniversitySuzhou 235200Anhui ProvinceChina

BACKGROUND Severe eyelid edema and blood accumulation in the submandibular space after preauricular fistula surgery is rarely *** SUMMARY We report a 4-year-old girl with eyelid edema and swelling of the submandibular region after preauricular fistula resection under general *** drug treatment failed,neck computed tomography examination was performed,which confirmed severe bleeding in the submandibular ***,exploration and ligation of the superficial temporal artery were performed under general anesthesia to stop the *** child was successfully treated,and there were no abnormalities over 1 year of *** When severe bleeding occurs after preauricular fistula surgery,superficial temporal artery rupture should be considered as a cause.

关键词： Preauricular lesions Bleeding Infection Excision Surgical treatment Case report

Extraction of iron and aluminum from high-iron bauxite by ammonium sulfate roasting and water leaching

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Journal of Iron and Steel Research International 2019年第6期26卷 578-584页

作者： Ding tian xiao-yi Shen Yu-chun Zhai Penny xiao Paul Webley School of Metallurgy Northeastern University Shenyang 110819 Liaoning China School of Material Science and Engineering Dalian Jiaotong University Dalian 11602& Liaoning China Liaoning Key Laboratory for Metallurgical Sensor and Technology Northeastern University Shenyang 110819 Liaoning China School of Resources and Materials Northeastern University at Qinhuangdao Qinhuangdao 066004 Hebei China Department of Chemical & Biomolecular Engineering University of Melbourne Melbourne 3010 VIC Australia

High iron content is one of the challenges in utilizing the refractory bauxites in China. An improved method for treating the high-iron bauxite by roasting with (NH4)2SO4 was proposed, which offers a possible alternative method for utilizing the high-iron bauxite. The influences of the roasting time, roasting temperature, material ratio, and ore particle size on the extraction ratios of Fe and Al were studied, and the orthogonal test was used to optimize the reaction conditions. The optimized reaction conditions were proposed as follows: roasting temperature of 450 °C, roasting time of 120 min, material ratio of (NH4)2SO4 to ore of 2.5:1.0, and ore particle size below 80 jim. The roasting mechanism and kinetic parameters including the apparent activation energy and reaction rate constant were investigated. The results showed that the control step of the roasting process was the internal diffusion on the product layer and the apparent activation energy was 19.22 kJ mol-1 in the reaction temperature range. The kinetic equation was obtained finally.

关键词： High-iron bauxite Ammonium sulfate Roasting Reaction process Kinetics

Melanin synthesis genes BgTH and BgDdc affect body color and cuticle permeability in Blattella germanica

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Insect Science 2022年第6期29卷 1552-1568页

作者： tian-tian Bai xiao-Jin Pei Tong-Xian Liu Yong-Liang Fan Shi-Ze Zhang State Key Laboratory of Crop Stress Biology for Arid Areas and Key Laboratory of lIntegrated Pest Management on Crops in Northwestern Loess Plateau Ministry of AgricultureNorthwest A&F UniversityYanglingShaanxiChina Present address:Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology and Institute of Insect Science and Technology School of Life SciencesSouth China Normal UniversityGuangzhou510631China

Melanin is involved in cuticle pigmentation and sclerotization of insects,which is critical for maintaining structural integrity and functional completeness of insect *** 2 key enzymes of tyrosine hydroxylase(TH)and dopa decarboxylase(DDC)predicted in melanin biosynthesis are usually conserved in ***,it is unclear whether their function is related to epidermal *** this study,we identified and cloned the gene sequences of BgTH and BgDdc from Blattella germanica,and revealed that they both showed a high expression at the molting,and BgTH was abundant in the head and integument while BgDdc was expressed highest in the fat *** RNA in-terference(RNAi),we found that knockdown of BgTH caused molting obstacles in some cockroaches,with the survivors showing pale color and softer integuments,while knock-down of BgDdc was viable and generated an abnormal light brown body *** assay showed that the dsBgTH-injected adults died earlier than control groups under a dry atmosphere,but dsBgDdc-injected cockroaches did *** contrast,when dsRNA-treated cockroaches were reared under a high humidity condition,almost no cockroaches died in all ***,with eosin Y staining assay,we found that BgTH-RNAi resulted in a higher cuticular permeability,and BgDdc-RNAi also caused slight dye *** results demonstrate that BgTH and BgDdc function in body pigmentation and affect the waterproofing ability of the cuticle,and the reduction of cuticular perme-ability may be achieved through cuticle melanization.

关键词： cuticular permeability desiccation tolerance dopa decarboxylase German cockroach pigmentation tyrosine hydroxylase