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Defence Technology（防务技术） 2022年第6期18卷 1065-1072页

作者： Xing-yu Wu Ming-yu Li qing-xuan Zeng qing-xia yu State Key Laboratory of Explosion and Technology Beijing Institute of TechnologyBeijing100081PR China

Copper azide with high density was successfully synthesized by in-situ reaction of nanoporous copper(NPC)precursor with HN_(3) *** with pore size of about 529 nm has been prepared by electroless plating using polystyrene(PS)as *** copper shells thickness of NPC was controlled by adjusting the PS loading *** effects of copper shell on the morphology,structure and density of copper azide were *** conversion increased from 87.12%to 95.31%when copper shell thickness decrease from 100 to 50 ***,the density of copper azide prepared by 529 nm NPC for 24 h was up to 2.38 g/cm^(3).The hollow structure of this NPC was filled by swelling of copper azide which guaranteed enough filling volume for keeping the same shape as well as improving the charge ***,HNS-IV explosive was successfully initiated by copper azide with minimum charge thickness of 0.55 mm,showing that copper azide prepared has excellent initiation performance,which has more advantages in the application of miniaturized explosive systems.

关键词： Nanoporous copper Electroless plating In-situ reaction Copper azide

Pollinator-dependent evolution of floral trait combinations in an orchid herb

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Journal of Plant Ecology 2020年第4期13卷 450-459页

作者： yun Wu Xu-yu Duan Yong Xiang Shao-Bin weng Jin-yu Zhong Jing Li qing-Jun Li School of Civil Engineering Architecture and EnvironmentXihua UniversityChengdu 610039China yunnan Key Laboratory of Plant Reproductive Adaption and Evolutionary Ecology Kunming 650091China Laboratory of Ecology and Evolutionary Biology Yunnan UniversityKunming 650091China South-East Tibetan Plateau Station for Integrated Observation and Research of Alpine Environment Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Landscape Architecture Sichuan Agricultural UniversityChengdu 611130China

Aims As one of the most important agents driving floral evolution,pollinators shape the diversity of flowers in ***,most previous studies have only quantified pollinators driving the evolution of a single floral trait,and experimental estimates of the potential role of pollinators in shaping the evolution of floral trait associations are relatively *** We experimentally identified and estimated the pollinator-mediated directional and correlational selection on single floral traits and trait combinations across 2 years in an orchid species,Spiranthes *** Findings Pollinators mediated directional selection for an earlier flowering start date and larger corolla *** mediated positive correlational selection on the combinations of floral display traits and negative correlational selection on the combinations of flowering phenology and floral display *** addition,the strength of selection differed over *** results highlight the potential role of pollinators in driving the evolution of floral trait combinations and suggest that it is necessary to consider floral character functional associations when seeking to understand and predict the evolutionary trajectory of flowers in angiosperms.

关键词： directional and correlational selection floral evolution pollinator-mediated selection Spiranthes sinensis trait combinations

Signal molecule-mediated hepatic cell communication during liver regeneration

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World Journal of Gastroenterology 2009年第46期15卷 5776-5783页

作者： Zhen-yu Zheng Shun-Yan weng Yan yu School of Agricultureand Biology Shanghai Jiao Tong University Shanghai 200240China

Liver regeneration is a complex and well-orchestrated process,during which hepatic cells are activated to produce large signal molecules in response to liver injury or mass *** signal molecules,in turn,set up the connections and cross-talk among liver cells to promote hepatic *** this review,we endeavor to summarize the network of signal molecules that mediates hepatic cell communication in the regulation of liver regeneration.

关键词： Signal molecule Hepatic cells Cellular cross-talk Signal communication Liver regeneration

Microstructure of Ni-Based Self-Fluxing Alloy Coating(PartⅠ)

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Journal of Iron and Steel Research International 2005年第1期12卷 50-53页

作者： HUI Wei-jun DONG Han weng yu-qing WANG Mao-qiu CHEN Si-lian SHI Jie Central Iron and Steel Research Institute Chinese Society for Metals

The delayed fracture behaviors of CrMo-type high strength steels containing different amount of titanium(0to 0.10%)were *** steels were quenched at 880℃ and tempered from 400℃ to 650℃,and a wide range of tensile strength was *** sustained load tensile test was carried out by using notched tensile specimens in Walpole *** experimental results showed that with higher strength,the Ti-microalloyed steels show higher resistance to delayed fracture compared with non-microalloyed steel due to titanium beneficial role and microstructure *** undissolved TiC is uniformly distributed as strong hydrogen traps,retarding or preventing the diffusion and accumulation of hydrogen to lower-interaction energy sites,such as prior austenite and martensite lath boundaries in stress concentration ***,the grain refining effect of titanium is also an important factor to improve the delayed fracture resistance of Ti-microalloyed *** characteristics of delayed fracture remain nearly the same with titanium addition.

关键词： titanium delayed fracture high strength steel CrMo steel

掺杂磷烯二维纳米材料对草甘膦吸附机理的研究

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原子与分子物理学报 2025年第4期42卷 58-64页

作者：王群周乃武单正莉覃庆雨刘钰佳王梅梅青刚孙玉希绵阳师范学院生命科学与技术学院绵阳621006 绵阳师范学院化学与化学工程学院绵阳621000 绵阳师范学院光致功能材料重点实验室绵阳621006 曲阜师范大学生命有机分析重点实验室曲阜273165 北京市食品风味化学重点实验室北京100048

草甘膦是世界上普遍使用的除草剂之一,被广泛使用在农田和非农田杂草的防治.由于草甘膦类除草剂的大范围应用,其对动植物的危害性逐渐受到人们的关注.磷烯二维纳米材料与草甘膦之间相互作用机理的研究对草甘膦的检测及去除具有重大的意... 详细信息

草甘膦是世界上普遍使用的除草剂之一,被广泛使用在农田和非农田杂草的防治.由于草甘膦类除草剂的大范围应用,其对动植物的危害性逐渐受到人们的关注.磷烯二维纳米材料与草甘膦之间相互作用机理的研究对草甘膦的检测及去除具有重大的意义.本研究将采用基于密度泛函理论方法考察本征及Al,Ca,Ti及Fe金属原子掺杂的磷烯对草甘膦的吸附,通过吸附能,差分电荷密度,布居电荷分析本征及金属原子掺杂磷烯对草甘膦的吸附机制,从分子和原子水平上研究它们之间的详细机理.研究结果有望为掺杂磷烯材料在草甘膦吸附方面的应用提供有意义的理论参考.

关键词：磷烯掺杂磷烯草甘膦密度泛函理论

Methods for determining unimpeded aircraft taxiing time and evaluating airport taxiing performance

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Chinese Journal of Aeronautics 2017年第2期30卷 523-537页

作者： yu Zhang qing Wang Civil and Environmental Engineering University of South Florida College of Air Traffic Management Civil Aviation University of China College of Transportation Engineer Tongji University

The objective of this study is to improve the methods of determining unimpeded（nominal） taxiing time,which is the reference time used for estimating taxiing delay,a widely accepted performance indicator of airport surface *** reviewing existing methods used widely by different air navigation service providers（ANSP）,new methods relying on computer software and statistical tools,and econometrics regression models are *** models are highly recommended because they require less detailed data and can serve the needs of general performance analysis of airport surface *** proposed econometrics model outperforms existing ones by introducing more explanatory variables,especially taking aircraft passing and over-passing into the considering of queue length calculation and including runway configuration,ground delay program,and weather *** length of the aircraft queue in the taxiway system and the interaction between queues are major contributors to long taxi-out *** proposed method provides a consistent and more accurate method of calculating taxiing delay and it can be used for ATM-related performance analysis and international comparison.

关键词： Aircraft taxiing Airport performance Econometric regression modeling Queue length Simulation analysis Taxiway system

Short-term emergency response planning and risk assessment via an integrated modeling system for nuclear power plants in complex terrain

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Frontiers of Earth Science 2013年第1期7卷 1-27页

作者： Ni-Bin CHANG yu-Chi weng Department of Civil Environmental and Construction Engineering University of Central Florida Orlando FL 32816 USA Division of Environmental Engineering Graduate School of Engineering Hokkaido University Hokkaido Sapporo 060-8628 Japan

Short-term predictions of potential impacts from accidental release of various radionuclides at nuclear power plants are acutely needed, especially after the Fukushima accident in Japan. An integrated modeling system that provides expert services to assess the consequences of accidental or intentional releases of radioactive materials to the atmosphere has received wide attention. These scenarios can be initiated either by accident due to human, software, or mechanical failures, or from intentional acts such as sabotage and radioIogicaI dispersal devices. Stringent action might be required just minutes after the occurrence of accidental or intentional release. To fulfill the basic functions of emergency preparedness and response systems, previous studies seldom consider the suitability of air pollutant dispersion models or the connectivity between source term, disper- sion, and exposure assessment models in a holistic context for decision support. Therefore, the Gaussian plume and puff models, which are only suitable for illustrating neutral air pollutants in fiat terrain conditional to limited meteorological situations, are frequently used to predict the impact from accidental release of industrial sources. In situations with complex terrain or special meteorological conditions, the proposing emergency response actions might be questionable and even intractable to decision- makers responsible for maintaining public health and environmental quality. This study is a preliminary effort to integrate the source term, dispersion, and exposure assessment models into a Spatial Decision Support System （SDSS） to tackle the complex issues for short-term emergency response planning and risk assessment at nuclear power plants. Through a series model screening procedures, we found that the diagnostic （objective） wind field model with the aid of sufficient on-site meteorological monitoring data was the most applicable model to promptly address the trend of local wind field patt

关键词： emergency response nuclear power plants diagnostic model particle model source term model spatial analysis Spatial Decision Support System

Hepatectomy with primary closure of common bile duct for hepatolithiasis combined with choledocholithiasis

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World Journal of Gastroenterology 2015年第12期21卷 3564-3570页

作者： Chang-Ku Jia Jie weng You-Ke Chen qing-Zhuang Yang yu Fu Qi-Fan Qin Wei-Ming yu Department of Hepatobiliary Pancreatic Surgery The Affiliated Hospital of Hainan Medical College Department of General Surgery Lin’gao County Hospital Department of General Surgery Lin’an Municipal Hospital

AIM: To evaluate the feasibility of hepatectomy and primary closure of common bile duct for intrahepatic and extrahepatic calculi. METHODS: From January 2008 to May 2013, anatomic hepatectomy followed by biliary tract exploration without biliary drainage(non-drainage group) was performed in 43 patients with intrahepatic and extrahepatic calculi. After hepatectomy, flexible choledochoscopy was used to extract residual stones and observe the intrahepatic bile duct and common bile duct(CBD) for determination of biliary stricture and dilatation. Function of the sphincter of Oddi was determined by manometry of the CBD. Primary closure of the CBD without T-tube drainage or bilioenteric anastomosis was performed when there was no biliary stricture or sphincter of Oddi dysfunction. Dexamethasone and anisodamine were intravenously injected 2-3 d after surgery to prevent postoperative retrograde infection due to intraoperative bile duct irrigation, and to maintain relaxation of the sphincter of Oddi, respectively. During the same period, anatomic hepatectomy followed by biliary tract exploration with biliary drainage(drainage group) was performed in 48 patients as the control group. Postoperative complications and hospital stay were compared between the two ***: There was no operative mortality in either group of patients. Compared to intrahepatic and extrabiliary drainage, hepatectomy with primary closure of the CBD(non-drainage) did not increase the incidenceof complications, including residual stones, bile leakage, pancreatitis and cholangitis(P > 0.05). Postoperative hospital stay and costs were nevertheless significantly less in the non-drainage group than in the drainage group. The median postoperative hospital stay was shorter in the non-drainage group than in the drainage group(11.2 ± 2.8 d vs 15.4 ± 2.1 d, P = 0.000). The average postoperative cost of treatment was lower in the non-drainage group than in the drainage group(29325.6 ± 5668.2 yuan vs 32933.3

关键词： Hepatolithiasis Choledocholithiasis Primary closur

Insights into efficient transition metal-nitrogen/carbon oxygen reduction electrocatalysts

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Journal of Energy Chemistry 2021年第5期30卷 470-485页

作者： Hao-yu Wang Chen-Chen weng Zhong-Yong yuan National Institute for Advanced Materials School of Materials Science and EngineeringNankai UniversityTianjin 300350China

It is of vital importance to accelerate the sluggish oxygen reduction reaction(ORR)process at the cathode with earth-abundant metal-based catalysts for the commercialization of low-temperature polymer electrolyte membrane fuel *** consideration of high catalytic activity,long-term stability and low cost of potential ORR electrocatalysts,transition metal species have attracted much interest and transition metal-nitrogen-carbon(M-N/C,M=Fe,Co,Ni,Mn,etc.)catalysts have been widely considered as the most promising non-precious metal catalysts for ***,the fundamental understanding of ORR catalytic mechanism and the identification of active centers are briefly introduced,and then different M-N/C catalysts classified by precursors with the strategies for design and optimization are *** challenges and possible opportunity for future development of high-performance ORR catalysts are finally proposed.

关键词： Electrocatalysis Oxygen reduction reaction Metal-nitrogen/carbon Fuel cell

Delayed diagnosis of arytenoid cartilage dislocation after tracheal intubation in the intensive care unit:A case report

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World Journal of Clinical Cases 2022年第15期10卷 5119-5123页

作者： weng-qing Yan Chen Li Zhi Chen Medical Department of Graduate School Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Emergency Jiangxi Provincial People’s HospitalNanchang 330006Jiangxi ProvinceChina Department of Traumatology Jiangxi Provincial People’s HospitalNanchang 330006Jiangxi ProvinceChina

BACKGROUND Arytenoid cartilage dislocation is a rare and often overlooked complication of tracheal intubation or blunt laryngeal *** most common symptom is persistent *** cases of arytenoid dislocation due to tracheal intubation are reported more frequently in otolaryngology,reports on its occurrence in the intensive care unit(ICU)are *** report a case of delayed diagnosis of arytenoid cartilage dislocation after tracheal intubation in the *** SUMMARY A 20-year-old woman was referred to the ICU following a fall from a *** voice was normal;laryngeal computed tomography showed unremarkable findings on ***,due to deterioration of the patient’s condition,tracheal intubation,and emergency exploratory laparotomy followed by laparoscopic surgery two d later under general anesthesia were *** extubation,the patient was sedated and could not communicate *** the 10th day after extubation,the patient complained of hoarseness and coughing with liquids,which was attributed to laryngeal edema and is common after tracheal ***,specific treatment was not ***,the patient’s symptoms did not *** d later,an electronic laryngoscope examination revealed dislocation of the left arytenoid *** patient underwent arytenoid closed reduction under general anesthesia by an experienced *** symptoms improved *** sixmonth follow up revealed that the hoarseness had resolved within four weeks of the reduction *** Symptoms of arytenoid cartilage dislocation are difficult to identify in the ICU leading to missed or delayed diagnosis among patients.

关键词： Arytenoid cartilage dislocation Intensive care unit Tracheal intubation Persistent hoarseness Risk factors Case report