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Chinese Journal of Aeronautics 2024年第9期37卷 369-384页

作者： Xiaofeng LI Jian TIAN cheng wei Xibin CAO School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing Instiuteof Spacecraft System Engineering China Academy of Space TechnolgyBeijing 100094Chia

With the rapid development of space activities,non-cooperative space targets increase swiftly,such as failed satellites and upper stages,threating normal spacecrafts *** there are some problems in the capture process,such as excessive collision and fast tumbling of targets,manipulator with redundant Degrees of Freedom(DOFs)can be used to improve the compliance and therefore solve these *** Rope-Driven Snake Manipulator(RDSM)is a combina-tion of hyper-redundant DOFs and better compliance,and therefore it is suitable for capturing *** this paper,a snake manipulator mechanism is designed,and the complete kinematic model and system dynamic model considering RDSM,target and contact is ***,to obtain the configuration of joint with hyper-redundant DOFs,an improved motion dexterity index is pro-posed as the joint motion optimization ***,the force-position collaborative optimization index is designed to adjust active stiffness,and the impedance control method based on the modified index is used to capture the space ***,the proposed force-position collaborative opti-mization method is verified by virtual prototype *** results demonstrate that based on the proposed method,the collision force is reduced by about 25%compared to normal impe-dance control,showing higher safety.

关键词： Capturing non-cooperative spacetargets Rope-driven snakemanipu-lator Force-position collaborative optimization Redundant degrees of free-dom Active stiffness adjustment

The Rediscovery of“Evocation”(Xing)and the Rise of“Poems Based on Evocation with Miscellaneous Themes”(Za-Xing)in the Resurgence Era of Southern Song Dynasty

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2024年第3期18卷 336-352页

作者： cheng wei School of Liberal Arts and Chinese Poetry Research Center Anhui Normal UniversityWuhu 241002China

The composition of group poems based on evocation with miscellaneous themes(za-xing)first emerged in the Tang Dynasty,pioneered by Du Fu and Chu Guangxi,but an extraordinary outburst of group poems based on evocation with miscellaneous themes emerged in the the resurgence era of Southern Song *** phenomenon was not only influenced by new ideas in poetics and the studies of Confucian classics in the Southern Song Dynasty but also directly stemmed from the resistance against the poetic system represented by the Jiangxi poetry *** group poems based on evocation with miscellaneous themes of poets such as Lu You,Yang Wanli,and Fan chengda exhibit a tendency opposite to the Jiangxi poetic style in terms of their overall *** rise of evocation with miscellaneous themes poems in the poetic circle of the the resurgence era of Southern Song Dynasty holds significant importance in the history of Song *** represents a rebellious and rule-breaking force that fundamentally protests against the various rules and boundaries established by Song poetics,marking a revolution in the norms of Song poetry.

关键词： the resurgence era of Southern Song Dynasty poems based on evocation with miscellaneous themes origin meaning

The abundance,distribution,and enrichment mechanism of harmful trace elements in coals from Guizhou,Southwestern China

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Acta Geochimica 2024年第5期43卷 889-903页

作者： Hui Hou wei cheng Ruidong Yang Yan Zhang College of Mining Guizhou UniversityGuiyangChina National and Local Joint Laboratory of Engineering for Effective Utilization of RegionalMineral Resources from Karst Areas GuiyangChina Guizhou Key Laboratory of Comprehensive Utilization of Non-Metallic Mineral Resources GuiyangChina College of Resource and Environment Engineering Guizhou UniversityGuiyangChina

Coal seams can enrich a variety of harmful trace elements under specific geological *** spatial distribution of harmful trace elements in coal is extremely uneven,and the distribution characteristics of each element content are *** harmful elements released in the process of coal mining and utilization will cause serious harm to the environment and the human *** is of great resource significance to study the geochemistry of coal that affects the enrichment and distribution characteristics of harmful trace *** on the domestic and foreign literature on coal geochemistry in Guizhou published by previous investigators,this study counted 1097 sample data from 23 major coal-producing counties in Guizhou Province,systematically summarized the relevant research results of harmful trace elements in the coal of Guizhou,and revealed the overall distribution and enrichment characteristics of harmful trace elements in the coal of *** results show that the average contents of Cd,Pb,Se,Cu,Mo,U,V,As,Hg,and Cr in coal of Guizhou are higher than those in Chinese coal and world coal.A variety of harmful trace elements in the coal of Guizhou have high background values,especially in Liupanshui,Xingyi and Qianbei *** enrichment of various harmful trace elements in the Late Permian coal in Guizhou is mainly related to the combined action of various geological and geochemical *** supply of terrigenous debris and sedimentary environment may be the basic background of the enrichment of harmful elements in western Guizhou,while low-temperature hydrothermal activity and volcanic ash deposition may be the main reasons for the enrichment of harmful elements in southwestern Guizhou.

关键词： Harmful trace elements Distribution characteristics Enrichment law Geological and geochemical features Guizhou

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Zinc-based metal-organic frameworks as efficient carriers for anticancer drug to reduce toxicity and increase efficacy

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Rare Metals 2024年第10期43卷 5152-5163页

作者： Dong-wei Ma Jing-Sheng Lu Xiang-Xin Cao Yan-wei cheng Gang Wang Zi-Qian Zhang Bo-cheng Chen Ning Lin Qing Chen College of Pharmacy Guangxi Scientific Research Center of Traditional Chinese MedicineGuangxi University of Chinese Medicine Guangxi Zhuang Yao Medicine Center of Engineering and Technology

The rational design of a specific co-drug delivery platform that can address the unavoidable resistance, toxic side effects and low targeting efficiency of traditional cancer treatments is of great ***, Zn-based MOF-zeolitic imidazole framework-90(ZIF-90) was selected as the drug delivery carrier, with the cancer therapeutic drug mercaptopurine(6-MP) and glucose oxidase(GOD) as the drug models, hyaluronic acid(HA) was used for protection and targeted delivery, which designed and fabricated an intelligent drug delivery platform(6-MP@ZIF-90@GOD@HA). This platform aims to reduce the toxic side effects of 6-MP and enhance its efficacy while improving the targeting ability of GOD,thereby further enhancing the treatment outcome. Notably,results from both in vitro and in vivo experiments demonstrate that the targeted synergistic chemo/reactive oxygen species(ROS)-mediated/starvation therapy inhibited the cancer cell growth while reducing the chemotherapy toxicity, which provides new possibilities for the development of more precise and effective treatment strategies.

关键词： Cancer treatment Combination therapy Drug delivery Metal-organic framework Reduced toxicity

Electromagnetic scattering and imaging simulation of extremely large-scale sea-ship scene based on GPU parallel technology

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Journal of Electronic Science and Technology 2024年第2期22卷 16-23页

作者： cheng-wei Zhang Zhi-Qin Zhao wei Yang Li-Lai Zhou Hai-Yu Zhu Southwest China Institute of Electronic Technology Chengdu610036China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Tencent Company Shenzhen518054China

Aiming to solve the bottleneck problem of electromagnetic scattering simulation in the scenes of extremely large-scale seas and ships,a high-frequency method by using graphics processing unit(GPU)parallel acceleration technique is *** the implementation of different electromagnetic methods of physical optics(PO),shooting and bouncing ray(SBR),and physical theory of diffraction(PTD),a parallel computing scheme based on the CPU-GPU parallel computing scheme is realized to balance computing ***,a multi-GPU framework is further proposed to solve the computational difficulty caused by the massive number of ray tubes in the ray tracing *** using the established simulation platform,signals of ships at different seas are simulated and their images are achieved as *** is shown that the higher sea states degrade the averaged peak signal-to-noise ratio(PSNR)of radar image.

关键词： Multi graphics processing unit Radar imaging Sea-ship Shooting and bouncing rays

Tunable VO_(2) cavity enables multispectral manipulation from visible to microwave frequencies

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Light(Science & Applications) 2024年第3期13卷 510-518页

作者： Hang wei Jinxin Gu Tao Zhao Zhiyuan Yan He-Xiu Xu Shuliang Dou cheng-wei Qiu Yao Li Center for Composite Materials and Structure Harbin Institute of TechnologyHarbin 150001China National University of Singapore Department of Electrical&Computer EngineeringSingapore 117583Singapore School of Chemical Engineering and Technology Harbin Institute of TechnologyHarbin 150001China Suzhou Laboratory Suzhou 215123China

Optical materials capable of dynamically manipulating electromagnetic waves are an emerging field in memories,optical modulators,and thermal ***,their multispectral design preliminarily attracts much attention,aiming to enhance their efficiency and integration of ***,the multispectral manipulation based on these materials is challenging due to their ubiquitous wavelength dependence restricting their capacity to narrow *** this article,we cascade multiple tunable optical cavities with selective-transparent layers,enabling a universal approach to overcoming wavelength dependence and establishing a multispectral platform with highly integrated *** on it,we demonstrate the multispectral(ranging from 400 nm to 3 cm),fast response speed(0.9 s),and reversible manipulation based on a typical phase change material,vanadium *** platform involves tandem VO_(2)-based Fabry–Pérot(F-P)cavities enabling the customization of optical responses at target bands *** can achieve broadband color-changing capacity in the visible region(a shift of~60 nm in resonant wavelength)and is capable of freely switching between three typical optical models(transmittance,reflectance,and absorptance)in the infrared to microwave regions with drastic amplitude tunability exceeding *** work represents a state-of-art advance in multispectral optics and material science,providing a critical approach for expanding the multispectral manipulation ability of optical systems.

关键词： spectral microwave visible

Work-function-induced interfacial electron redistribution of MoO_(2)/WO_(2) heterostructures for high-efficiency electrocatalytic hydrogen evolution reaction

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Rare Metals 2024年第2期43卷 489-499页

作者： Tong-Fei Li Jing Li Lu-Ping Zhang Jia-wei Ke Meng-Xing Fan Li-Fang Zhang cheng-wei Deng Yi Sun Tao Qian cheng-Lin Yan School of Chemistry and Chemical Engineering Nantong UniversityNantong226019China Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Centre of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing210023China Aerospace Hydrogen Energy Technology(Shanghai)Co.Ltd. Shanghai201800China Key Laboratory of Core Technology of High Specific Energy Battery and Key Materials for Petroleum and Chemical Industry College of EnergySoochow UniversitySuzhou215006China Light Industry Institute of Electrochemical Power Sources Suzhou215006China

The engineering of the electronic configurations of active sites,together with the production of more accessible active sites through heterostructure design,has been established as a forceful methodology for boosting water electrolysis ***,a facile approach is developed to fabricate well-dispersed MoO_(2) and WO_(2) nanoparticles with abundant heterointerfaces entrapped in N,P-doped carbon nanofibers(referred to as MoO_(2)/WO_(2)@N,P-CNFs hereafter)as hydrogen evolution reaction(HER)electrocatalysts in alkaline and acidic *** spectroscopic analyses and theoretical findings manifest that the heterointerface formed by the work function modulation of MoO_(2)/WO_(2) triggers the spontaneous electron redistribution from MoO_(2)to WO_(2) and a built-in electric field,which is essential to promote water adsorption,optimize the H-intermediate adsorption energy,result in the enhanced charge transfer efficiency,and ultimately increase the intrinsic HER ***,the intimate confinement of MoO_(2)/WO_(2) heterostructures in the porous carbon substrate can restrain the active sites from unfavorable coarsening and detachment,thus ensuring facilitated HER kinetics and outstanding structural *** a result,MoO_(2)/WO_(2)@N,P-CNFs exhibit superior catalytic HER performance in acidic and basic solutions,requiring 118 and 95 mV overpotentials to achieve 10 mA·cm^(−2),respectively,surpassing a number of reported non-noble metal-based *** work provides guidelines for the rational design and construction of special metallic heterocomponents with optimized interfacial electronic structure for various electrochemical technologies.

关键词： Electrospinning MoO_(2)/WO_(2) heterostructure Work function Hydrogen evolution reaction

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Missing Value Imputation for Radar-Derived Time-Series Tracks of Aerial Targets Based on Improved Self-Attention-Based Network

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Computers, Materials & Continua 2024年第3期78卷 3349-3376页

作者： Zihao Song Yan Zhou wei cheng Futai Liang Chenhao Zhang Department of Early Warning Intelligence Early Warning AcademyWuhan430019China

The frequent missing values in radar-derived time-series tracks of aerial targets(RTT-AT)lead to significant challenges in subsequent data-driven ***,the majority of imputation research focuses on random missing(RM)that differs significantly from common missing patterns of *** method for solving the RM may experience performance degradation or failure when applied to RTT-AT *** autoregressive deep learning methods are prone to error accumulation and long-term dependency *** this paper,a non-autoregressive imputation model that addresses the issue of missing value imputation for two common missing patterns in RTT-AT is *** model consists of two probabilistic sparse diagonal masking self-attention(PSDMSA)units and a weight fusion *** learns missing values by combining the representations outputted by the two units,aiming to minimize the difference between the missing values and their actual *** PSDMSA units effectively capture temporal dependencies and attribute correlations between time steps,improving imputation *** weight fusion unit automatically updates the weights of the output representations from the two units to obtain a more accurate final *** experimental results indicate that,despite varying missing rates in the two missing patterns,our model consistently outperforms other methods in imputation performance and exhibits a low frequency of deviations in estimates for specific missing *** to the state-of-the-art autoregressive deep learning imputation model Bidirectional Recurrent Imputation for Time Series(BRITS),our proposed model reduces mean absolute error(MAE)by 31%~50%.Additionally,the model attains a training speed that is 4 to 8 times faster when compared to both BRITS and a standard Transformer model when trained on the same ***,the findings from the ablation experiments demonstrate that the PSDMSA,the weight fusion unit,cascade network design

关键词： Missing value imputation time-series tracks probabilistic sparsity diagonal masking self-attention weight fusion

Preservation of superior rectal artery in laparoscopic colectomy:The best choice for slow transit constipation?

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2362-2364页

作者： Yi-Lei Liu wei-cheng Liu Department of Gastrointestinal Surgery Second Affiliated Hospital of Naval Medical University(Shanghai Changzheng Hospital)Shanghai 200003China Department of Colorectal and Anal Surgery(Clinical Center for Pelvic Floor Surgery) Zhongnan Hospital of Wuhan UniversityWuhan 430071Hubei ProvinceChina

Laparoscopic colectomy with ileorectal anastomosis may be beneficial for patients with slow transit constipation who do not respond to conservative treatment,particularly if the superior rectal artery(SRA)is *** important concerns have been addressed in this *** is important to first go over the definition of surgical procedure as it is used in this ***,the current study lacked a control group that had SRA ***,it would be best to use a prospective,randomized controlled ***,a description of the mesenteric defect’s state following a laparoscopic colectomy is necessary.

关键词： Laparoscopic colectomy Slow transit constipation Ileorectal anastomosis Superior rectal artery Anastomotic leak

Facet effects on bimetallic ZnSn hydroxide microcrystals for selective electrochemical CO2 reduction

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Green Energy & Environment 2024年第8期9卷 1314-1320页

作者： Liu Han cheng-wei Wang Shan-shan Luo Ying-tang Zhou Bing Li Ming Liu School of Chemistry and Chemical Engineering Harbin Institute of Technology National Engineering Research Center for Marine Aquaculture Marine Science and Technology CollegeZhejiang Ocean University

Employing crystal facets to regulate the catalytic properties in electrocatalytic carbon dioxide reduction reaction（eCO2RR） has been well demonstrated on electrocatalysts containing single metals but rarely explored for bimetallic systems. Here, we synthesize Zn Sn（OH）6（ZSO）microcrystals（MCs） with distinct facets and investigate the facet effects in eCO2RR. Electrochemical studies and in situ Fourier Transform Infrared Spectroscopy（in situ-FTIR） reveal that ZSO MCs produce mainly C1 products of HCOOH and CO. The {111} facet of the ZSO MCS exhibits higher selectivity and faradaic efficiency（FE） than that of the {100} facet over a wide range of potentials（-0.9 V ～-1.3 V versus RHE）. Density Functional Theory（DFT） calculations elucidate that the {111} facet is favorable to the adsorption/activation of CO2molecules,the formation of intermediate in the rate-determining step, and the desorption of C1 products of CO and HCOOH molecules.

关键词： ZnSn(OH) 6 Crystal facets Electrochemical carbon dioxide reduction C1 product Density functional theory