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Fundamental aspects of alkyne semi-hydrogenation over heterogeneous catalysts

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Nano Research 2022年第12期15卷 10044-10062页

作者： Zhe Wang Qian Luo Shanjun Mao Chunpeng Wang Jinqi Xiong Zhirong Chen Yong Wang Advanced Materials and Catalysis group Center of Chemistry for Frontier TechnologiesState Key Laboratory of Clean Energy UtilizationInstitute of CatalysisDepartment of ChemistryZhejiang UniversityHangzhou310028China College of Chemical and Biological Engineering Zhejiang UniversityHangzhou310028China

Alkyne semi-hydrogenation is extremely significant for the production of polymer-grade ethylene and lots of fine chemicals in modem *** efforts had been devoted to regulate the electronic and geometric structure of active ensembles for suppressing side reactions,including over-hydrogenation and *** strategies,such as alloying,surface decoration,atomization of metal centers,and others,were developed to promote the selective production of target alkenes in alkyne *** this review,the basic principles within reaction mechanisms and catalyst optimization would be discussed in *** an updated perspective to the fabrication of next-generation catalysts for alkyne semi-hydrogenation is also provided.

关键词： heterogeneous catalysis alkyne semi-hydrogenation metal-based catalysts catalytic mechanism

Modeling and finite element analysis of rod and wire steel rolling process

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Journal of University of Science and Technology Beijing 2008年第4期15卷 412-419页

作者： Shulun Liao Liwen Zhang Siyu Yuan Yu Zhen Shuqi Guo School of Materials Science and Engineering Dalian University of Technology Dalian 116023 China State Key Laboratory of Materials Modification by Laser Ion and Electron Beams Dalian University of Technology Dalian 116023 China Dongbei Special Steel group Dalian 116031 China

Two thermomechanical coupled elastic-plastic finite element （FE） models were developed for predicting the 12-pass continuous rolling process of GCrl 5 rod and wire steel. The distances between stands in the proposed models were set according to the actual values, and the billets were shortened in the models to reduce the calculation time. To keep the continuity of simulation, a technique was developed to transfer temperature data between the meshes of different models in terms of nodal parameters by interpolation functions. The different process variables related to the rolling process, such as temperature, total equivalent plastic strain, equivalent plastic strain rate, and contact friction force, were analyzed. Also, the proposed models were applied to analyze the reason for the occurrence of an excessive spread in width. Meanwhile, it was also utilized to assess the influence of the roll diameter change on the simulated results such as temperature and rolling force. The simulated results of temperature are found to agree well with the measured results.

关键词： width spread rod rolling wire rolling temperature rolling force numerical simulation

Use of the Spatial kD-Tree in Computational Physics Applications

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Communications in Computational Physics 2007年第3期2卷 545-576页

作者： A.Khamayseh G.Hansen Computer Science and Mathematics Division Oak Ridge National LaboratoryOak RidgeTN 37831USA. Multiphysics Methods group Idaho National LaboratoryIdaho FallsIDUSA.

The need to perform spatial queries and searches is commonly encountered within the field of computational *** development of applications ranging from scientific visualization to finite element analysis requires efficient methods of locating domain objects relative to general locations in *** of the time,it is possible to form and maintain spatial relationships between objects either explicitly or by using relative motion constraints as the application evolves in ***,either due to unpredictable relative motion or the lack of state information,an application must perform a general search(or ordering)of geometric objects without any explicit spatial relationship information as a *** previous state information involving domain geometric objects is not available,it is typically an involved and time consuming process to create object adjacency information or to order the objects in ***,as the number of objects and the spatial dimension of the problem domain is increased,the time required to search increases *** paper proposes an implementation of a spatial k-d tree(skD-tree)for use by various applications when a general domain search is *** skD-tree proposed in this paper is a spatial access method where successive tree levels are split along different *** are indexed by their centroid,and the minimum bounding box of objects in a node are stored in the tree *** paper focuses on a discussion of efficient and practical algorithms for multidimensional spatial data structures for fast spatial query *** functions include the construction of a skD-tree of geometric objects,intersection query,containment query,and nearest neighbor query operations.

关键词： Geometric query bounding volume hierarchy skD-tree containment query mesh generation h-refinement remapping.

Electrically Tunable Energy Bandgap in Dual-Gated Ultra-Thin Black Phosphorus Field Effect Transistors

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Chinese Physics Letters 2017年第4期34卷 87-91页

作者： Shi-Li Yan Zhi-Jian Xie Jian-Hao Chen Takashi Taniguchi Kenji Watanabe International Center for Quantum Materials Peking University Beijing 100871 High Pressure group National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki 305-0044 Japan Collaborative Innovation Center of Quantum Matter Beijing 100871

The energy bandgap is an intrinsic character of semiconductors, which largely determines their properties. The ability to continuously and reversibly tune the bandgap of a single device during real time operation is of great importance not only to device physics but also to technological applications. Here we demonstrate a widely tunable bandgap of few-layer black phosphorus （BP） by the application of vertical electric field in dual-gated BP field-effect transistors. A total bandgap reduction of 124 meV is observed when the electrical displacement field is increased from 0.10 V/nm to 0.83 V/nm. Our results suggest appealing potential for few-layer BP as a tunable bandgap material in infrared optoelectronies, thermoelectric power generation and thermal imaging.

关键词： Electrically Tunable Energy Bandgap in Dual-Gated Ultra-Thin Black Phosphorus Field Effect Transistors FET BP

Pushing the limits of liver surgery for colorectal liver metastases:Current state and future directions

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World Journal of Gastrointestinal Surgery 2019年第2期11卷 34-40页

作者： Raphael LC Araujo Marcelo M Linhares Department of Digestive Surgery Escola Paulista de Medicina-UNIFESP Department of Oncology Americas Medical Service/Brazil United Health Group Postgraduation Program Barretos Cancer Hospital

Liver surgery for the treatment of colorectal liver metastases is the standard treatment in a dynamic surgical field with many variables that should be considered in a curative intent scenario. Hepatectomy for colorectal liver metastases has undergone constant changes over the last 30 years, including indications until the need for rescue procedures of recurrent and advanced diseases as well as minimally invasive surgery. These advancements in liver surgery have not only resulted from overall improvements in the surgical field but have also resulted from a better understanding of the biological behavior of the disease, liver regeneration, and homeostasis during and after *** in anesthesiology, intensive care medicine, radiology, and surgical devices have correlated with further advancements of hepatectomies. Moreover,changes are still forthcoming, and both fields of augmented reality and artificial intelligence will likely have future contributions in this field in regard to both diagnoses and the planning of procedures. The aim of this editorial is to emphasize several aspects that have contributed to the paradigm shifts in colorectal liver metastases surgery over the last three decades as well as to discuss the factors concerning patient selection and the technical aspects of liver surgery. Finally, this editorial will highlight the promising new features of this surgery for diagnoses and treatments in this field.

关键词： Colorectal liver metastases Cancer Hepatectomy Liver Surgery Oncology

Loading System for Full-Scale Heavy-Duty Support Node Test with Multi-Directional Loading Requirements

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Transactions of Tianjin University 2011年第3期17卷 166-174页

作者：王玉银龚超张素梅郭海山 School of Civil Engineering Harbin Institute of Technology Central Research Institute of Building and Construction Co. Ltd. MCC Group China State Construction Engineering Co. Ltd.

This paper presents the design, analysis and experimental study of a loading system for heavy-duty nodes test based on a large-scale multi-directional in-plane loading device, which has been used in a full-scale heavy-duty support node test. Test loads of the support reached 6 567 kN with multi-directional loading requirements, which outrange the capacity of the available loading devices. Through the reinforcement of a large-scale multi-directional inplane loading device, the innovative design of a self-balanced load transferring device, and other arrangement considerations of the loading system, the test was implemented and the loading capacity of the ring was considerably enlarged. Due to the heavy loading requirements, some checking computations of the ring and the load transferring device outranged the limit of the Chinese national code "Code for Design of Steel Structures (GB 50017—2003)", thus elastic-plastic finite element (FE) analysis was carried out on the two devices, and also the real-time monitoring on the whole loading systems during experiments to ensure test safety. FE analysis and test results show that the loading system worked elastically during experiments.

关键词： loading system self-balanced design multi-directional loading heavy-duty node

Photonics for net zero

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Advanced Photonics 2022年第1期4卷 2-4页

作者： John R.Lincoln Photonics Leadership group and Harlin Ltd. SalisburyUnited Kingdom

Achieving net zero will be the biggest technological challenge of the 21^(st)century.A truly global,all-pervasive challenge impacting every application,market,and *** are no guidelines,instructions,or silver bullets that provide overnight *** net zero will be a sum of countless innovations across energy generation,resource efficiency,and waste *** will have a pivotal role in all of these;directly,by reducing the carbon impact from using light-based technologies;and indirectly,through increased use of photonics in monitoring and reduction in greenhouse gasses across a vast range of industries.

关键词： technology silver Photonics

Modeling and optimization of large-scale sapphire crystal growth process using HEM and Ky methods

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Modeling and optimization of large-scale sapphire crystal gr...

Reaction mechanism and kinetics of pressurized pyrolysis of Chinese oil shale in the presence of water

第十七届全国晶体生长与材料学术会议(CCCG-17)

作者： Vasif Mamedov Vladimir Artemyev Andrei Vorob’ev Andrey Smirnov Vladimir Kalaev STR group Inc.

Sapphire crystals are used for production of high-brightness light-emitted diodes and devices,products in optics,medicine instruments and in other applications[1].Requirements for crystal quality and price motivate crystal manufacturers for optimization of crystal growth technology to increase furnace productivity and

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Petroleum Science 2012年第4期9卷 532-534页

作者： FANG Chaohe LI Shuyuan MA Guili WANG Hongyan HUANG Zhilong China University of Petroleum ChangpingBeijing 102249China Research Institute of Petroleum Exploration and Development-Langfang Hebei 065007China Shenhua Ningxia Coal Industry group Coal-Chemical Company Ningxia 951000China

A study of reaction mechanisms and chemical kinetics of pressurized pyrolysis of Chinese Liushuhe oil shale in the presence of water were conducted using an autoclave for simulating and modeling in-situ underground thermal *** was found that the oil shale was first pyrolyzed to form pyrobitumen,shale oil,shale gas and residue,then the pyrobitumen was further pyrolyzed to form more shale oil,shale gas,and *** means that there are two consecutive and parallel *** increasing temperature,the pyrobitumen yield,as intermediate,first reached a maximum,then decreased to approximately *** kinetics results show that both these reactions are first *** activation energy of pyrobitumen formation from oil shale is lower than that of shale oil formation from pyrobitumen.

关键词： Oil shale pyrobitumen pressurized pyrolysis in-situ underground retorting reaction mechanism chemical kinetics