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CuInS_(2)quantum-dot-modified g-C_(3)N_(4)S-scheme heterojunction photocatalyst for hydrogen production and tetracycline degradation

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Journal of Materials Science & Technology 2024年第5期172卷 145-155页

作者： Jingjing Zhang Yue Zhao Kezhen qi shu-yuan Liu College of Pharmacy Dali UniversityDali 671000China Department of Pharmacology Shenyang Medical CollegeShenyang 110034China

CuInS_(2)quantum-dot(CIS QD)-modified g-C_(3)N_(4)(CN)catalysts(CIS/CN)were prepared with the aid of an in-situ growth *** as-obtained photocatalysts were explored by measuring their crystallinity,surface morphology,binding energy and light absorption *** photocatalytic efficiency of the pho-tocatalysts was evaluated through photocatalytic water splitting for hydrogen production and tetracycline(TC)antibiotic degradation under the simulated solar light and visible light *** optimized sample(10CIS/CN)showed the best photocatalytic activity:producing 102.4μmol g^(-1)h^(-1)of hydrogen in 1 h,or degrading 52.16%of TC in 120 min,which were respectively 48 or 3.4 times higher than the photocatalytic activity of CN *** enhancement in the efficiency of the composite system was prin-cipally accredited to the enlargement of light absorption,the more effective in charge transfer and the dropping of the charge carrier pair recombination through a formed S-scheme heterojunctional *** work is an effort to adjust CN-based polysulfide QD for speedy *** enriched photo-catalytic activity grants a new sense for adjusting the optical properties of CN.

关键词： CuInS_(2)QDs g-C_(3)N_(4) Photocatalysis Hydrogen production S-scheme heterojunction

Recent advances and challenges in task-oriented dialog systems

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Science China(Technological Sciences) 2020年第10期63卷 2011-2027页

作者： ZHANG Zheng TAKANOBU Ryuichi zhu qi HUANG MinLie zhu XiaoYan Department of Computer Science&.Technology Tsinghua UniversityBeijing 100084China Institute for Artificial Intelligence Tsinghua University(THUAI)Beijing 100084China Beijing National Research Center for Information Science&Technology Beijing 100084China

Due to the significance and value in human-computer interaction and natural language processing,task-oriented dialog systems are attracting more and more attention in both academic and industrial *** this paper,we survey recent advances and challenges in task-oriented dialog *** also discuss three critical topics for task-oriented dialog systems:(1)improving data efficiency to facilitate dialog modeling in low-resource settings,(2)modeling multi-turn dynamics for dialog policy learning to achieve better task-completion performance,and(3)integrating domain ontology knowledge into the dialog ***,we review the recent progresses in dialog evaluation and some widely-used *** believe that this survey,though incomplete,can shed a light on future research in task-oriented dialog systems.

关键词： task-oriented dialog systems natural language understanding dialog policy dialog state tracking natural language generation

Detailed study of RF properties of cold models for CW window-type RFQ

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Nuclear Science and Techniques 2018年第11期29卷 194-200页

作者： qi Fu Kun zhu Yuan-Rong Lu Zhi Wang shu-Li Gao Fang-Jian Jia Yuan He State Key Laboratory of Nuclear Physics and Technology Peking University Institute of Modern Physics China Academy of Science

A 50 mA CW deuteron RFQ is being built for a joint 973 project between Peking University and the Institute of Modern Physics. This RFQ adopts a high-frequency window-type structure. To study its RF properties and to validate the reliability of an electromagnetic simulation, two full-length aluminum models with tuners were built in succession. RF measurements were obtained from the test bench and compared to the simulations, including frequencies, quality factors, and electric fields of different modes and the field in aperture. Through field tuning, the maximal field unflatness for a single quadrant and the average asymmetry of four quadrants were reduced from 8.7% and ± 3.6% to 5.8% and ± 1.7%, ***, a tuning method of adjusting the gap distance between the endplates and the vanes was also studied in this paper.

关键词： CW RFQ Cold model RF measurement Magnetic coupling window

A unified framework of temporal information expression in geosciences knowledge system

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Geoscience Frontiers 2023年第5期14卷 343-352页

作者： shu Wang Yunqiang zhu Yanmin qi Zhiwei Hou Kai Sun Weirong Li Lei Hu Jie Yang Hairong Lv State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China University of Nottingham Ningbo China Faculty of Science and EngineeringNingbo 315154China Guangzhou Institute of Geography Guangdong Academy of SciencesGuangzhou 510070China University of Chinese Academy of Sciences Beijing 100101China Department of Automation Tsinghua UniversityBeijing 100084China

Time is an essential reference system for recording objects,events,and processes in the field of *** are currently various time references,such as solar calendar,geological time,and regional calendar,to represent the knowledge in different domains and regions,which subsequently entails a time conversion process required to interpret temporal information under different time ***,the current time conversion method is limited by the application scope of existing time ontologies(e.g.,“Jurassic”is a period in geological ontology,but a point value in calendar ontology)and the reliance on experience in conversion *** issues restrict accurate and efficient calculation of temporal information across different time *** address these issues,this paper proposes a Unified Time Framework(UTF)in the geosciences knowledge *** to a systematic time element parsing from massive time references,the proposed UTF designs an independent time root node to get rid of irrelevant nodes when accessing different time types and to adapt to the time expression of different geoscience ***,this UTF carries out several designs:to ensure the accuracy of time expressions by designing quantitative relationship definitions;to enable time calculations across different time elements by designing unified time nodes and structures,and to link to the required external ontologies by designing adequate *** comparing the time conversion methods,the experiment proves the UTF greatly supports accurate and efficient calculation of temporal information across different time references in SPARQL ***,it shows a higher and more stable performance of temporal information queries than the time conversion *** the advent of the Big Data era in the geosciences,the UTF can be used more widely to discover new geosciences knowledge across different time references.

关键词： Unified Time Framework(UTF) Time ontology Geosciences knowledge system Time conversion Time scale Big data

Plasma Generation in Air by Intense Laser Pulses with Various Pulse Durations

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Chinese Physics Letters 1999年第8期16卷 580-582页

作者： qiN Yuan-dong YANG Hong WANG shu-feng zhu Chang-jun GONG qi-huang Department of Physics Mesoscopic Physics LaboratoryPeking UniversityBeijing 100871

We have studied the plasma generation through collecting the charged particles produced in laser-induced break-down in atmospheric *** breakdovn is produced by ultrashort laser pulses with various durations ranging from 200fs to 2ps at a fixed pulse energy of *** found that the plasma yield increases first with the increment of pulse duration and then reaches a plateau at a duration longer than *** generated plasma temperature is estimated to be higher than 5x 10^(5)K.

关键词： pulse laser ultrashort

Value-added formate production from selective ethylene glycol oxidation based on cost-effective self-supported MOF nanosheet arrays

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Rare Metals 2022年第11期41卷 3654-3661页

作者： Lei Jiao Wenbo Wei Xiaofang Li Cheng-Bin Hong shu-Guo Han Muhammad Imran Khan qi-Long zhu College of Chemistry and Materials Science Fujian Normal UniversityFuzhou350007China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences(CAS)Fuzhou350002China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108China Research Institute of Sciences and Engineering(RISE) University of SharjahSharjah27272United Arab Emirates University of Chinese Academy of Sciences Beijing100049China

In order to realize electrochemical upgrading and improve the energy conversion efficiency,an ingenious strategy of constructing a thermodynamically favorable oxidation reaction to replace oxygen evolution reaction(OE... 详细信息

关键词： replace constructing glycol

Effect of tempering on bonding characteristics of cross wedge rolling 42CrMo/Q235 laminated shafts

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Journal of Iron and Steel Research International 2020年第10期27卷 1170-1178页

作者： shuai zhu Wen-fei Peng Xue-dao shu Zhejiang Provincial Key Laboratory of Part Rolling Technology Ningbo UniversityNingbo 315211ZhejiangChina

To further improve the comprehensive properties of 42CrMo/Q235 laminated shafts produced by cross wedge *** treatment of the shafts was *** and bending tests were carried out to compare the changes in mechanicalproperties before and after heat *** results showed that the interfacial bonding strength increased most aftertempering at 350℃for 45 *** microstructure of the interface was observed using a digital *** resultsshowed that the dispersed oxides on the interface were basically eliminated by using the scheme of tempering at 350 cand holding for 45 *** reasons for the change in mechanical properties were explained from the point of theinterfacial *** electron microscopy was used to analyze the micro-morphology of the tensile *** was observed that after tempering at 350℃and holding for 45 min,the dimple holes became larger and deeper,and thestructure of fracture became more uniform and *** the point of the tensile fracture *** reasons for thechange in mcchanical propcrties wcrc explained as well.

关键词： Heat treatment Cross wedge rolling Interface Microstructure Fracture morphology

Multilayer perceptron neural network activated by adaptive Gaussian radial basis function and its application to predict lid-driven cavity flow

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Acta Mechanica Sinica 2021年第12期37卷 1757-1772页

作者： qinghua Jiang Lailai zhu Chang shu Vinothkumar Sekar Department of Mechanical Engineering National University of Singapore10 Kent Ridge CrescentSingapore 117576Singapore

To improve the performance of multilayer perceptron(MLP)neural networks activated by conventional activation functions,this paper presents a new MLP activated by univariate Gaussian radial basis functions(RBFs)with adaptive centers and widths,which is composed of more than one hidden *** the hidden layer of the RBF-activated MLP network(MLPRBF),the outputs of the preceding layer are first linearly transformed and then fed into the univariate Gaussian RBF,which exploits the highly nonlinear property of *** RBFs might address the issues of saturated outputs,low sensitivity,and vanishing gradients in MLPs activated by other prevailing nonlinear ***,we apply four MLP networks with the rectified linear unit(ReLU),sigmoid function(sigmoid),hyperbolic tangent function(tanh),and Gaussian RBF as the activation functions to approximate the one-dimensional(1D)sinusoidal function,the analytical solution of viscous Burgers’equation,and the two-dimensional(2D)steady lid-driven cavity *** the same network structure,MLP-RBF generally predicts more accurately and converges faster than the other ***-RBF using less hidden layers and/or neurons per layer can yield comparable or even higher approximation accuracy than other MLPs equipped with more layers or neurons.

关键词： Multilayer perceptron neural network Activation function Radial basis function Numerical approximation

Using cholecystokinin to facilitate endoscopic clearance of large common bile duct stones

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World Journal of Gastroenterology 2014年第29期20卷 10121-10127页

作者： Tao Tao qi-Jie Zhang Ming Zhang Xiao zhu shu-Xia Sun Yan-qing Li Department of Gastroenterology Qilu Hospital of Shandong University Department of Gastroenterology Zi Bo Central Hospital Department of Rehabilitation Zi Bo Central Hospital Guangdong Province Key Laboratory of Medical Molecular Diagnosis Guangdong Medical College Department of Gynecology Zi Bo Central Hospital

AIM: To evaluate the effect of cholecystokinin (CCK) during extracorporeal shockwave lithotripsy (ESWL) in the clearance of common bile duct (CBD) stones in endoscopic retrograde cholangiopancreatography (ERCP).

关键词： Common bile duct stones Extracorporeal shockwave lithotripsy Endoscopic retrograde cholan-giopancreatography Cholecystokinin