检索结果-南通市图书馆

World Journal of Gastrointestinal Surgery 2024年第4期16卷 1195-1202页

作者： Chen Lin Zi-Yan Wang Liang-Bo Dong zhi-wei Wang Ze-Hui Li wei-Bin Wang Department of General Surgery Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of General Surgery Peking Union Medical College HospitalBeijing 100730China Interventional Section Department of RadiologyPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China

BACKGROUND Percutaneous transhepatic stent placement has become a common strategy for the postoperative treatment of portal vein(PV)/superior mesenteric veins(SMV)stenosis/*** has been widely used after liver transplantation surgery;however,reports on stent placement for acute PV/SMV stenosis after pancreatic surgery within postoperative 3 d are *** SUMMARY Herein,we reported a case of intestinal edema and SMV stenosis 2 d after pancreatic *** patient was successfully treated using stent *** the stenosis resolved after stent placement,complications,including bleeding,pancreatic fistula,bile leakage,and infection,made the treatment highly *** use of anticoagulants was adjusted multiple times to prevent venous thromboembolism and the risk of *** careful treatment,the patient stabilized,and stent placement effectively managed postoperative PV/SMV *** Stent placement is effective and feasible for treating acute PV/SMV stenosis after pancreatic surgery even within postoperative 3 d.

关键词： Pancreaticoduodenectomy Portal vein reconstruction Portal vein stenosis Portal vein stent Case report

Design and fabrication of lightweight AlCrFeNiTix compositionally complex alloys with exceptional specific strength

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第7期43卷 3314-3328页

作者： Jun-zhi Li wei-Zong Bao Jie Chen Bo-Hua Yu Kun Zuo Tian Gao Ze-Yun Cai Guo-Qiang Xie School of Materials Science and Engineering Harbin Institute of Technology (Shenzhen) State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology

This study focuses on compositionally complex alloys（CCAs）,aiming to achieve a balance between high strength and low density for new energy and aerospace *** composition of AlCrFeNiTixCCAs is strategically guided by employing density functional theory and the theoretical design of thermodynamic *** CCAs,particularly AlCrFeNiTi0.25alloy,demonstrate remarkable specific yield strength（1640.8 MPa） and 22.7% maximum *** incorporation of Ti facilitates the formation of lightweight and high-strength L21phase,contributing to the overall high specific *** effects of grain boundary strengthening,solid solution strengthening,Orowan strengthening and Peierls flow stress further enhance *** exploration of micros tructural changes during fracture reveals the role of ordered phases in suppressing crack propagation and absorbing energy within disordered phases,thereby improving the toughness and fracture resistance of *** methods and discoveries establish a robust foundation for advancing the development of novel lightweight CCAs.

关键词： Lightweight Compositionally complex alloys Specific yield strength

Functional decoration on a regenerable bifunctional porous covalent organic framework probe for rapid detection and adsorption of copper ions

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第2期43卷 758-769页

作者： Yu-Long Li Xi-Lang Jin Yi-Ting Ma Jing-Rui Liu Fazal Raziq Peng-Yuan Zhu zhi-Feng Deng Hong-wei Zhou wei-Xing Chen Wen-Huan Huang School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an710021China Yulin Boyi-Jingking Research Institute of Industrial Technology Development Research Yulin719054China KAUST Catalysis Center King Abdullah University of Science and Technology23955-6900ThuwalKingdom of Saudi Arabia Key Laboratory of Chemical Additives for China National Light Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and TechnologyXi’an710021China National and Local Joint Engineering Laboratory for Slag Comprehensive Utilization and Environmental Technology School of Materials Science and EngineeringShaanxi University of TechnologyHanzhong723001China

Developing fluorescence porous probe for detecting and eliminating Cu^(2+) contamination in water or biosystem is an essential research project that has attracted considerable ***,improving the fluorescence detecting efficiency while enhancing the adsorption capacity of the porous probe is of great ***,a bifunctional two-dimensional imine-based porous covalent organic framework(TTP-COF)probe was designed and synthesized from 1,3,5-tris(4-aminophenyl)benzene(TAPB)and 2,4,6-Triformylphloroglucinol(TP)***-COF displayed rapid detection of Cu^(2+)(limit of detection(LOD)=10 nmol·L^(−1) while achieving a high adsorption capacity of 214 mg·g^(−1)(pH=6)at room temperature with high reusability(>5 cycles).The key roles and contributions of highπ-conjugate and delocalized electrons in TABP and functional–OH groups in TP were *** importantly,the fluorescence quenching mechanism of TTP-COF was studied by density functional theory theoretical calculations,revealing the crucial role of intramolecular hydrogen bonds among C=N and–OH groups and the blocking of the excited state intramolecular proton transfer process in detecting process of Cu^(2+).

关键词： Covalent organic framework(COF) Excited-state intramolecular proton transfer(ESIPT) Copper ion detection Copper ion adsorption Renewability

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-Bo Cheng Peng Zeng Chuan-zhi Zang Qing-wei Dong Guang-Xi Wan Xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

Sulfur doped iron-nitrogen-hard carbon nanosheets as efficient and robust noble metal-free catalysts for oxygen reduction reaction in PEMFC

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第2期89卷 422-433,I0010页

作者： Bin Liu Jiawang Li Bowen Yan Qi wei Xingyu Wen Huarui Xie Huan He Pei Kang Shen zhi Qun Tian Collaborative Innovation Center of Sustainable Energy Materials School of Physical Science and TechnologyGuangxi UniversityGuangxi Key Laboratory of Electrochemical Energy MaterialsState Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite StructuresNanning 530004GuangxiChina

Transition metal-nitrogen-carbon(M-N-C)as a promising substitute for the conventional noble metalbased catalyst still suffers from low activity and durability for oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).To tackle the issue,herein,a new type of sulfur-doped ironnitrogen-hard carbon(S-Fe-N-HC)nanosheets with high activity and durability in acid media were developed by using a newly synthesized precursor of amide-based polymer with Fe ions based on copolymerizing two monomers of 2,5-thiophene dicarboxylic acid(TDA)as S source and 1,8-diaminonaphthalene(DAN)as N source via an amination *** as-synthesized S-Fe-N-HC features highly dispersed atomic Fe Nxmoieties embedded into rich thiophene-S doped hard carbon nanosheets filled with highly twisted graphite-like microcrystals,which is distinguished from the majority of M-N-C with soft or graphitic carbon *** unique characteristics endow S-Fe-N-HC with high ORR activity and outstanding durability in 0.5 M H_(2)SO_(4).Its initial half-wave potential is 0.80 V and the corresponding loss is only 21 m V after 30,000 ***,its practical PEMFC performance is a maximum power output of 628.0 mW cm^(-2)and a slight power density loss is 83.0 m W cm^(-2)after 200-cycle practical ***,theoretical calculation shows that the activity of Fe Nxmoieties on ORR can be further enhanced by sulfur doping at meta-site near FeN_(4)*** results evidently demonstrate that the dual effect of hard carbon substrate and S doping derived from the precursor platform of amid-polymers can effectively enhance the activity and durability of Fe-N-C catalysts,providing a new guidance for developing advanced M-N-C catalysts for ORR.

关键词： Transition metal-nitrogen-carbon Oxygen reduction reaction Hard carbon Amide based polymer reaction Proton exchange membrane cells

Megafossils of Betulaceae from the Oligocene of Qaidam Basin and their paleoenvironmental and phytogeographic implications

在线全文

学校读者我要写书评

暂无评论

Plant Diversity 2024年第1期46卷 101-115页

作者： Tao yang Jia-Hao Cai Yan-zhi Dai Hong-Yu Chen Lei Han Li Zhang wei-Yu Liang Xu-Jun Li Wen-Jia Li Jing-Yu Wu San-Ping Xie De-Fei Yan School of Earth Sciences and Key Laboratory of Mineral Resources in Western China(Gansu Province) Lanzhou UniversityLanzhou 730000China Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Center for Research and Education on Biological Evolution and Environments School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China

Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant *** Qaidam Basin has long been regarded as an ideal‘field laboratory’to investigate the paleoclimate and paleobiological evolution of the northern Tibetan ***,fossil angiosperms from the Qaidam Basin are rare,and our knowledge of its paleovegetation is ***,we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou Formation of northwestern Qaidam Basin(Huatugou area).Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus *** findings,together with other reported fossil plants from the same locality,reveal a close floristic linkage between the Qaidam Basin and Europe during the *** northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late *** floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies,which transported moisture and provided favorable climatic ***,fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest,which differs from the region’s modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene.

关键词： Paleoenvironment Biogeography Betulaceous fossil Qaidam basin Tibetan Plateau Oligocene

Auxiliary ball milling to prepare WS_(2)/graphene nanosheets composite for lithium-ion battery anode materials

在线全文

学校读者我要写书评

暂无评论

Tungsten 2024年第1期6卷 124-133页

作者： Yong-Lin Wu Jia-Bin Hong wei-Xu Zhong Chun-Xiang Wang zhi-Feng Li Sydorov Dmytro Jiangxi Provincial Key Laboratory of Power Batteries and Materials Jiangxi University of Science and TechnologyGanzhou 341000China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China Institute of Bioorganic Chemistry and Petrochemistry National Academy of Sciences of UkraineKiev 02160Ukraine

A novel nano-WS_(2)/graphene nanosheets(GNSs)composite is obtained by ball milling with xylitol as auxiliary agent and hightemperature *** improves the shear force during ball milling and well overcomes the van der Waals interactions between the interlayer of graphite and WS_(2).Through high-temperature calcination,GNSs and WS_(2) nanosheets can form tight interface *** produced WS_(2)/GNSs composites can be used as anode materials for lithium-ion batteries,while maintaining a high reversible specific capacity of 705 mAh·g^(-1)with the capacity retention of 95%at a current density of 250 mA·g^(-1)after 200 cycles,mainly because WS_(2)/GNSs composites have a higher Li^(+)diffusion coefficient of 2.2×10^(-9)cm^(2)·s^(-1)and a higher specific surface area of 70.10 m^(2)·g^(-1).As a result,the xylitol-assisted ball milling method designed in this work is suitable for extended preparation of peeling of two-dimensional layer materials into nanosheets.

关键词： Lithium-ion battery Anode material WS_(2) Graphene nanosheets Auxiliary ball milling

Predictors of atrial fibrillation after coronary artery bypass graft： a meta-analysis

在线全文

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2009年第3期6卷 162-167页

作者： Liang Yin zhi-Nong Wang Yi-Feng Wang Wen-Tao Wang Guang-Yu Ji Xin-wei yang zhi-Yun Xu Department of Cardiothoracic Surgery Changhai Hospital Second Military Medical University of PLA Shanghai 200433 China

目的手术后的 atrial 纤维性颤动(AF ) 在经历冠的动脉的病人与不太有利的结果被联系了绕过接枝外科(CABG ) 并且可以导致增加的手术后的病态和死亡。出版研究的系统的评论和元分析被进行在 CABG 以后检验出现 AF 的风险因素。用 Medli... 详细信息

目的手术后的 atrial 纤维性颤动(AF ) 在经历冠的动脉的病人与不太有利的结果被联系了绕过接枝外科(CABG ) 并且可以导致增加的手术后的病态和死亡。出版研究的系统的评论和元分析被进行在 CABG 以后检验出现 AF 的风险因素。用 Medline 数据库， Cochrane 临床的试用数据库和联机临床的试用数据库的方法，我们考察了所有使随机化的控制试用(RCT ) 和在 CABG 以后检验 AF 的出现的风险因素的观察研究。我们寻找了因为文学出版了 2009 年 4 月或更早。结果我们的评论识别了 8 研究(观察研究) ，包含 14548 个病人，那在 CABG 以后检验了 AF 的出现的风险因素。尽管研究规定冲突结果，全面结果建议推进了年龄那，以前的高血压，桥容器的数字可以在 CABG 以后增加 AF 的出现糖尿病的没有重要差别，外科手术前的心肌的梗塞，并且 13 -Blocker 的外科手术前的药在 AF 病人和 no-AF patiens 之间被观察了。在 CABG，和 perioperative 药和照顾必须被加强减少以后，有先进年龄，以前的高血压和更高有的桥容器的更多的数字的结论病人为 AF 的出现冒险 AF 的手术后的出现。

关键词：冠状动脉移植旁路颤动心房 Medline数据库试验数据库自动对焦

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

火箭壳体加工的虚拟单元重构方法

控制与决策 2022年第11期37卷 2818-2826页

作者：杨从林向竹杨志伟谭跃进国防科技大学系统工程学院长沙410000

针对火箭壳体加工车间新订单连续到达,排产方案重构频繁导致重构时间花销大、排产方案低效等问题,首先建立虚拟单元重构的多目标规划模型,以多批订单总生产时间、运输设备总运输距离以及车间生产设备负荷均衡因素为目标函数,以车间设备... 详细信息

针对火箭壳体加工车间新订单连续到达,排产方案重构频繁导致重构时间花销大、排产方案低效等问题,首先建立虚拟单元重构的多目标规划模型,以多批订单总生产时间、运输设备总运输距离以及车间生产设备负荷均衡因素为目标函数,以车间设备加工能力和火箭壳体加工工艺限制为约束条件;其次提出一种改进的NSGA-Ⅱ算法对模型进行优化求解,针对NSGA-Ⅱ算法局部搜索能力的不足,在NSGA-Ⅱ算法交叉过程中引入“首次改进”和“随机改进”两种局部搜索策略,提高该算法的局部搜索能力;最后基于超体积、均匀性两个多目标评价指标对提出的改进NSGA-Ⅱ算法与传统的NSGA-Ⅱ算法以及NSGA-Ⅲ算法进行比较,结合实例验证了改进NSGA-Ⅱ算法在进行火箭壳体虚拟单元重构时更加高效.

关键词：火箭壳体虚拟单元重构负荷均衡 NSGA-Ⅱ算法局部搜索

Engineering singlet and triplet excitons of TADF emitters by different host-guest interactions

在线全文

学校读者我要写书评

暂无评论

Aggregate

Aggregate 2024年第1期5卷 337-344页

作者： wei Zhang Jie Kong Rui zhi An Jiachen Zhang Yujie Zhou Lin-Song Cui Meng Zhou Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefeiChina Key Laboratory of Precision and Intelligent Chemistry University of Science and Technology of China(USTC)HefeiChina CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefeiChina

Understanding the host-guest interactions for thermally activated delayed fluorescence(TADF)emitters is critical because the interactions between the host matrices and TADF emitters enable precise control on the optoelectronic performance,whereas technologically manipulating the singlet and triplet excitons by using different kinds of host-guest interactions remains ***,we report a comprehensive picture that rationalizes host-guest interaction-modulated exciton recombination by using time-resolved *** found that the early-time relaxation is accelerated in polar polymer because dipole-dipole interaction facilitates the stabilization of the 1CT ***,an opposite trend is observed in longer delay time,and faster decay in the less polar polymer is ascribed to theπ-πinteraction that plays the dominant role in the later stage of the excited *** findings highlight the technological engineering singlet and triplet excitons using different kinds of host-guest interactions based on their electronic characteristics.

关键词： host-guest interaction singlet TADF triplet