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Defence Technology（防务技术） 2023年第6期24卷 203-213页

作者： Ke-xin Wang li-xiao shen Bin Yuan Yan li Shun-guan Zhu lin Zhang Zhen-xin Yi Chen-guang Zhu School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210941China

Energetic metal-organic complexes have been involved in nanothermites as novel ***,the existing preparation methods often lead to mixing inhomogeneity and small contact area of ingredients,the reactivity and functionality of the novel energetic nanocomposites are still *** this work,spray crystallization(SC)method was used to prepare novel energetic nanocomposites,the high-energy metal-organic complex[Ni(CHZ)_(3)](ClO_(4))_(2)(CHZ=1,3-diaminourea)was composited with nanoaluminum(n-Al).Results showed that n-Al/[Ni(CH_(2))_(3)](ClO_(4))_(2)energetic nanocomposites prepared by SC method increased heat release to 2977.6 J/g and peak pressure to 3.91 MPa with higher pressurization rate(1324.06 MPa/s),decreased sensitivity thresholds(>100 mJ)to electrostatic discharge(ESD)and enhanced detonation ability compared with[Ni(CHZ)_(3)](ClO_(4))_(2)alone and physically mixed(PM)n-Al/[Ni(CHZ)_(3)](ClO_(4))_(2).These results proved that it is significant to introduce energetic metal-organic complexes with inherent high energy in new-concept n-Al/energetic metal-organic complexes nanocomposites through SC method for a better performance of its application.

关键词： Energetic metal-organic complexes Nano aluminum Energetic nanocomposites Spray crystallization Thermite reaction

Current-carrying tribological behavior of C/Cu contact pairs in extreme temperature and humidity environments for railway catenary systems

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Science China(Technological Sciences) 2024年第8期67卷 2537-2548页

作者： shen MingXue JI DeHui HU Qiang xiao li li QiuPing State Key Laboratory of Performance Monitoring and Protecting of Rail Transit Infrastructure East China Jiaotong UniversityNanchang 330013China School of Materials Science and Engineering East China Jiaotong UniversityNanchang 330013China Institute of Applied Physics Jiangxi Academy of SciencesNanchang 330095China

Many current-carrying contact pairs, such as those found in pantograph-catenary systems, operate in open environments and are susceptible to significant external interference from temperature and humidity variations. This study investigated the evolution of the friction coefficient and contact resistance of C/Cu contact pairs under alternating temperature, humidity, and current conditions. Through experimentation, the wear rate and microtopography of the worn surface were analyzed under various constant parameters. Subsequently, the differences in tribological behavior and current-carrying characteristics of the contact pairs under these three parameters were explored. The results revealed that the decrease in temperature resulted in a significant increase in the friction coefficient of the contact pairs, carbon wear, and copper surface roughness. Additionally, the surface oxidation rate was lower at lower temperatures. Moreover, contact resistance did not consistently increase with decreasing temperature, owing to the combined action of the contact area and the oxide film. Compared with temperature, humidity fluctuations at room temperature exerted less influence on the friction coefficient and contact resistance of the contact pairs. Dry environments rendered carbon materials vulnerable to oxidation and cracking, while excessive humidity fostered abrasive wear and arcing. High-current conditions generally degraded the tribological properties of C/Cu contacts. In the absence of current, the friction coefficient was extremely high, and the copper transfer was high. Under excessive current, copper was susceptible to plowing by carbon micro-bumps and abrasive particles, resulting in a decrease in the friction coefficient. The release of lipids from the carbon surface due to temperature elevation weakened the electrical contact performance and increased the occurrence of arc erosion, thereby exacerbating carbon wear.

关键词： temperature/humidity pantograph-catenary system C/Cu wear current-carrying friction sliding electrical contact

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Prognostic values of serum cystatin C and β2 microglobulin, urinary β2 microglobulin and N-acetyl-β-D-glucosaminidase in early acute renal failure after liver transplantation

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Chinese Medical Journal 2008年第14期121卷 1251-1256页

作者： HEI Zi-qing li xiao-yun shen Ning PANG Hong-yu ZHOU Shao-li GUAN Jian-qiang Department of Anesthesiology Third Affiliated Hospital Sun Yat-sen University Guangzhou Guangdong 510630 China

Background Acute renal failure （ARF） after liver transplantation is associated with high mortality and morbidity. Early therapeutic or preventive intervention is hampered by the lack of early effective prognostic factors. Recent studies indicated that serum levels of cystatin C and β2-microglobulin （β2 MG） as well as urinary β2 MG and N-acetyI-β-D- glucosaminidase （NAG） would increase in patients with early and mild renal impairment. In this study, these factors were detected during the different stages in patients who accepted orthotopic liver transplantation （OLT）, and their feasibilities to predict early ARF after OLT were also analyzed. Methods Sixty patients with normal blood urea nitrogen （BUN） and serum creatinine （SCr） who received modified piggyback liver transplantation without veno-venous bypass were prospectively studied. Blood samples were drawn from patients for the determination of serum β2 MG（n=60）, SCr （n=60） and serum Cystatin C （n=39） at following 5 intervals： before operation （TO）, 20 minutes before anhepatic phase （T1）, 25 minutes in anhepatic （T2）, 60 minutes after reperfusion （T3） and at the end of operation（T4）. Urinary B2 MG （n=60） and NAG （n=60） were also examined at following 3 intervals： before operation （TO）, 60 minutes after reperfusion （T3） and at the end of operation （T4）. According to the Rimola A criteria of ARF in 24 hours after operation, all the patients were divided into two groups： ARF group and non-ARF group. The data were statistically analyzed to evaluate the feasibiliy of regarding these factors as prognostic factors for early ARF after liver transplantation in patients with normal SCr and BUN before operation. Results Ten of sixty cases showed ARF（16.7%）. The Logistic regression analysis showed that the levels of serum and urinary β2 MG as well as serum cystatin C before operation were correlated with early ARF after liver transplantation （P 〈0.05）, while only serum levels of cystatin C and Cr at the end of operation c

关键词： liver transplantation acute renal failure cystatin C β2-microglobulin

Category of Generalized Intuitionistic Fuzzy Sets

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Chinese Quarterly Journal of Mathematics 2005年第2期20卷 192-199页

作者： YANGWan-cai lixiao-shen DepartmentofMathematicsandPhysics HenanUniversityofScienceandTechnologyLuoyang471003China

In this paper, category GIFS of generalized intuitionistic fuzzy sets(GIF) is built up. Topoi properties of category GIFS are studied. Firstly, it is proved that the category GIFS has all topoi properties except that it has no subobject classifiers, Secondly, it is proved that the category GIFS has middle object and consequently GIFS is a weak topos. Thirdly, by the use of theory of weak topos GIFS, the power object of an object in GIFS is studied.

关键词： category topos middle object weak topos generalized intuitionistic fuzzy set

Understanding the failure mechanism towards developing high-voltage single-crystal Ni-rich Co-free cathodes

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Green Energy & Environment 2024年第6期9卷 1045-1057页

作者： Jixue shen Bao Zhang Changwang Hao xiao li Zhiming xiao Xinyou He Xing Ou Engineering Research Center of the Ministry of Education for Advanced Battery Materials School of Metallurgy and EnvironmentCentral South UniversityChangsha410083China Zhejiang Power New Energy Co. Ltd.Zhuji311899China Material Science and Chemistry Engineering College China University of GeosciencesWuhan430074China

Benefited from its high process feasibility and controllable costs,binary-metal layered structured liNi_(0.8)Mn_(0.2)O_(2)(NM)can effectively alleviate the cobalt supply crisis under the surge of global electric vehicles(EVs)sales,which is considered as the most promising nextgeneration cathode material for lithium-ion batteries(liBs).However,the lack of deep understanding on the failure mechanism of NM has seriously hindered its application,especially under the harsh condition of high-voltage without sacrifices of reversible ***,singlecrystal liNi_(0.8)Mn_(0.2)O_(2) is selected and compared with traditional liNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM),mainly focusing on the failure mechanism of Cofree cathode and illuminating the significant effect of Co element on the li/Ni antisite defect and dynamic ***,the presence of high li/Ni antisite defect in NM cathode easily results in the extremely dramatic H2/H3 phase transition,which exacerbates the distortion of the lattice,mechanical strain changes and exhibits poor electrochemical performance,especially under the high cutoff ***,the reaction kinetic of NM is impaired due to the absence of Co element,especially at the single-crystal ***,the negative influence of li/Ni antisite defect is controllable at low current densities,owing to the attenuated ***,Co-free NM can exhibit better safety performance than that of NCM *** findings are beneficial for understanding the fundamental reaction mechanism of single-crystal Ni-rich Co-free cathode materials,providing new insights and great encouragements to design and develop the next generation of liBs with low-cost and high-safety performances.

关键词： li/Ni antisite defect Dynamic characteristic High-voltage Single-crystal Ni-rich Co-free cathodes lithium-ion batteries

Quantum support vector machine for multi classification

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Communications in Theoretical Physics 2024年第7期76卷 57-62页

作者： li Xu xiao-yu Zhang Ming li Shu-qian shen College of Science China University of PetroleumQingdao 266580China

Classical machine learning algorithms seem to be totally incapable of processing tremendous data,while quantum machine learning algorithms could deal with big data unhurriedly and provide exponential acceleration over classical *** this paper,we propose two quantum support vector machine algorithms for multi *** is the quantum version of the directed acyclic graph support vector *** other one is to use the Grover search algorithm before measurement,which amplifies the amplitude of the phase storing of the classification *** k classification,the former provides quadratic reduction in computational complexity when *** latter accelerates the training speed significantly and more importantly,the classification result can be read out with a probability of at least 50%using only one *** conduct numerical simulations on two algorithms,and their classification success rates are 96%and 88.7%,respectively.

关键词： quantum support vector machine quantum feature mapping Grover search algorithm

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Patterns of floristic inventory and plant collections in Myanmar

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Plant Diversity 2023年第6期45卷 302-308页

作者： Thant Sin Aung Alice CHughes Phyo Kay Khine Bo liu xiao-li shen Ke-Ping Ma State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China University of Hong Kong Department of Ecology and Biodiversity The University of Hong Kong School of Biological SciencesChina Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunYunnan 666303China Minzu University of China Beijing 100081China

Myanmar is one of the most biodiverse countries in the Asia-Pacific region due to a wide range of climatic and environmental *** diversity in Myanmar is largely unknown,resulting in a lack of comprehensive conservation *** developed a database of higher plants in Myanmar derived from herbarium specimens and literature sources,and analyzed patterns of diversity inventories and collection inconsistencies,aiming to provide a baseline floristic data of Myanmar and act as a guide for future research *** collected 1,329,354 records of 16,218 *** show that the collection densities at the township level was variable,with 5% of townships having no floristic *** ecoregion had an average collection density of greater than 1 specimen/km2and the lowest collection density was found in the Kayah-Karen Montane Rainforests,which covered 8% of Myanmar’s total *** highest sampling densities were found in Mandalay Region,Chin State,and Yangon *** floristic collections over the past three centuries,knowledge of the distribution of the vast majority of plant taxa remained limited,particularly for gymnosperms,pteridophytes,and *** botanical surveys and further analyses are needed to better describe Myanmar’s floristic *** important strategy to promote knowledge of the biodiversity patterns in Myanmar is to improve the collection and digitalization of specimens and to strengthen cooperation among countries.

关键词： Biodiversity Ecoregion Higher plants Hotspots Myanmar Specimens

Fat necrosis of liver in a patient with mixed type liver cirrhosis

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 535-537页

作者： li-Fang Shao xiao-Min shen Wei Yu Department of Nursing the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious Diseasesthe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

To the Editor: Fatty liver diseases, including nonalcoholic fatty liver disease and alcohol related fatty liver disease, have become a major public health concern [ 1, 2 ]. Fatty liver diseases have been shown to progress through various stages, from steatosis or necrosis with inflammation and hepatocyte damage to the development of fibrosis and eventual cirrhosis with an increased risk of carcinoma [ 2, 3 ].

关键词： cirrhosis diseases liver

Impact of transcranial electrical stimulation on serum neurotrophic factors and language function in patients with speech disorders

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World Journal of Clinical Cases 2024年第10期12卷 1742-1749页

作者： li Sun Kai xiao xiao-Yan shen Shu Wang Department of Rehabilitation Medicine General Hospital of the Yangtze River ShippingWuhan 430010Hubei ProvinceChina

BACKGROUND Speech disorders have a substantial impact on communication abilities and quality of *** treatments such as speech and psychological therapies frequently demonstrate limited effectiveness and patient *** electrical stimulation(TES)has emerged as a promising non-invasive treatment to improve neurological ***,its effectiveness in enhancing language functions and serum neurofactor levels in individuals with speech disorders requires further *** To investigate the impact of TES in conjunction with standard therapies on serum neurotrophic factor levels and language function in patients with speech *** In a controlled study spanning from March 2019 to November 2021,81 patients with speech disorders were divided into a control group(n=40)receiving standard speech stimulation and psychological intervention,and an observation group(n=41)receiving additional *** study assessed serum levels of ciliary neurotrophic factor(CNTF),glial cell-derived neurotrophic factor(GDNF),brainderived neurotrophic factor(BDNF),and nerve growth factor(NGF),as well as evaluations of motor function,language function,and development quotient *** After 3 wk of intervention,the observation group exhibited significantly higher serum levels of CNTF,GDNF,BDNF,and NGF compared to the control ***,improvements were noted in motor function,cognitive function,language skills,physical abilities,and overall development quotient *** is worth mentioning that the observation group also displayed superior perfor CONCLUSION This retrospective study concluded that TES combined with traditional speech and psychotherapy can effectively increase the levels of neurokines in the blood and enhance language function in patients with speech *** results provide a promising avenue for integrating TES into standard treatment methods for speech disorders.

关键词： Transcranial electrical stimulation Serum neurofactor levels Developmental level Language features

Precipitates and Hydrogen Permeation Behavior in Vanadium-Bearing Microalloyed Low Carbon Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 290-295页

作者： XU Chun,li xiao-jie,shen Da-guang (Material Engineering Department,Shanghai Institute of Technology,Shanghai 200233,China) Shanghai Inst Technol Dept Mat Engn Shanghai 200233 Peoples R China

The precipitates and hydrogen permeation behavior were studied in the low carbon steel for *** the preparation of samples,Ti containing and Ti free in vanadium-bearing microalloyed low carbon steel heating at 750℃ for 3 h,were adopted after *** was found that the a large number of fine VC,TiC,TiN and Ti 4 C 2 S 2 precipitates were in samples of Vanadium-bearing microalloyed low carbon steel with Ti *** fine VC,Fe 3 C and MnS precipitates were in steels without Ti *** the numbers of precipitates in the former is more bigger than the *** activation energies for hydrogen diffusion in both samples are 26.5 and 23.7 kJ/mol,*** at 25℃,the effective diffusion coefficients in the samples for Ti containing and Ti free in Vanadium-bearing microalloyed low carbon steel were measured as 2.71×10-6 and 4.22×10-6 cm 2 /s,*** fishscaling defect occurred in the former and heavy fishscaling defect in the later.

关键词： precipitate hydrogen permeability enameling vanadium-bearing microalloyed low carbon steel