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High-Temperature Stability of Mg-1Al-12Y Alloy Containing LPSO Phase and Mechanism of Its Portevin-Le Chatelier(PLC)Effect

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 982-998页

作者： Qian-Long Ren Shuai yuan Shi-yu Luan Jin-Hui Wang xiao-Wei Li xiao-yu liu Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial Engineering Research Center of High Performance Light Metal Alloys and FormingQinghai UniversityXining810016China School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China

In this study,the high-temperature stability and the generation mechanism of the Portevin-Le Chatelier(PLC)effect in solid-solution Mg-1Al-12Y alloy with different heat treatment processes were investigated by adjusting the content of long-period stacking ordered(LPSO)*** was found that the content of LPSO phases in the alloys differed the most after heat treatment at 530℃for 16 h and 24 h,with values of 13.56%and 3.93%***,high-temperature tensile experiments were conducted on these two alloys at temperatures of 150℃,200℃,250℃,and 300℃.The results showed that both alloys exhibited the PLC effect at temperatures ranging from 150 to 250℃.However,at a temperature 300℃,only the alloy with a greater concentration of LPSO phases exhibited the PLC effect,whereas the alloy with a lower proportion of LPSO phases did not exhibit this ***,both alloys exhibited remarkable high-temperature stability,with the alloy containing a greater percentage of LPSO phases also demonstrating superior *** underlying mechanism for this phenomenon lies in the exceptional high-temperature stability exhibited by the second phase within the ***,the LPSO phase effectively obstructs the movement of dislocations,and it also undergoing kinking to facilitate plastic deformation of the *** results indicate that the PLC effect can be suppressed by reducing dislocation pile-up at grain boundaries,which leads to a decrease in alloy plasticity but an increase in *** presence of the PLC effect in the WA121 alloy is attributed to the abundant dispersed second phase within the alloy,which initially hinders the movement of dislocations,leading to an increase in stress,and subsequently releases the dislocations,allowing them to continue their movement and thereby reducing in stress.

关键词： Magnesium alloy Long-period stacking ordered(LPSO)phase Portevin-Le Chatelier effect High temperature

A Study of the Simulation Model in WCDMA Systems

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The Journal of China Universities of Posts and Telecommunications 2002年第1期9卷 79-80页

作者： liu xiao yu directed by WU Wei ling

In this dissertation, we establish an end-to-end simulation model for the performance evaluation of WCDMA/ATM-based third-generation cellular systems where we take into account the quality of services in the integrated voice-data environment. This dissertation aims to provide a framework for performance analysis and evaluation of algorithms in mobile networks. In order to model such a complicated system, three challenges face us: modeling the wireless channel, modeling the traffic sources and modeling the broadband access network. In Chapter 1, the architecture of this system simulation model is concisely described. The author's contribution is to propose an abstract model of the air interface that has the same abstraction level as the broadband access network, which makes the integration of radio links and transport infrastructure feasible. The most important parts of this dissertation are in-depth researches on the three critical problems we mentioned above. Foreach topic, we derive an analytical model and implement it using Block Oriented Network Simulator (BONeS) of Cadence Corporation, *** Chapter 2, a digital channel model is established based on the simulation testbed which has developed successfully in the wireless communication laboratory in BUPT. This channel model is a key block in the abstract air-interface simulation module. The author's contributions are:

关键词： WCDMA system simulation network modeling mobile channel

Resolution Enhancement of SOHO/MDI Magnetograms

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Research in Astronomy and Astrophysics 2024年第6期24卷 358-367页

作者： Ying Qin Kai-Fan Ji Hui liu xiao-Guang yu yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China yunnan Key Laboratory of Solar Physics and Space Science Kunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China

Research on the solar magnetic field and its effects on solar dynamo mechanisms and space weather events has benefited from the continual improvements in instrument resolution and measurement *** augmentation and assimilation of historical observational data timelines also play a significant role in understanding the patterns of solar magnetic field *** the realm of astronomical data processing,super-resolution(SR)reconstruction refers to the process of using a substantial corpus of training data to learn the nonlinear mapping between low-resolution(LR)and high-resolution(HR)images,thereby achieving higherresolution astronomical *** paper is an application study in high-dimensional nonlinear *** learning models were employed to perform SR modeling on SOHO/MDI magnetograms and SDO/HMI magnetograms,thus reliably achieving resolution enhancement of full-disk SOHO/MDI magnetograms and enhancing the image resolution to obtain more detailed *** this study,a data set comprising 9717pairs of data from 2010 April to 2011 February was used as the training set,1332 pairs from 2011 March were used as the validation set and 1034 pairs from 2011 April were used as the test *** data preprocessing,we randomly cropped 128×128 sub-images as the LR cases from the full-disk MDI magnetograms,and the corresponding 512×512 sub-images as HR ones from the HMI full-disk magnetograms for model *** tests conducted have shown that the study successfully produced reliable 4×SR reconstruction of full-disk MDI *** MESR model's results(0.911)were highly correlated with the target HMI magnetographs as indicated by the correlation coefficient ***,the method achieved the best PSNR,SSIM,MAE and RMSE values,indicating that the MESR model can effectively reconstruct magnetograms.

关键词： magnetic fields techniques:image processing virtual observatory tools Sun:magnetic fields

Trace Element Mobility in Subducted Marble and Associated Eclogite:Constraints from UHP Rocks in the Shuanghe Area,Central-East China

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Journal of Earth Science 2024年第1期35卷 1-15页

作者： Xingao Hou Zhiqiang yu Shefa Chen Lei liu Yilin xiao Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

In order to decipher element mobility in UHP meta-sedimentary rocks in the continental subduction zone,major and trace element compositions are investigated for a continuous profile from a representative UHP region in the Dabie *** the lithologic contact zone,contents of K,Ca,LREE,and LILE exhibit varying degrees of downward trends in both marble and eclogite toward the contact zone,indicating that marble and their associated eclogite can release a large amount of K,Ca,and a small number of LILEs and *** is the main Ti phase in both marble and *** rims around rutile can occasionally be seen in *** of Ti and HFSE exhibit a well-coupled relation among marble and eclogite,indicating that substantial Ti and HFSEs were migrated from eclogite to marble,in accord with the capacity of a melt *** and titanites in marble exhibit a relatively limited variation in Nb/Ta ratios(12.9-16.2),similar to those of titanites in eclogite(14.2-16.7),which demonstrates that rutiles and titanites in marble were sourced from eclogite because of short-distance migrations of Ti and *** to the P-T path and the temperature and pressure conditions of the peak metamorphism reported by previous studies,the eclogite associated with marble may not form supercritical fluids in the subduction zone because of the addition of carbonate minerals.

关键词： UHP metamorphism eclogite marble element migration fluid actions geochemistry

Translational Enhancer of Tobacco mosaic virus Enhancing Expression of Hepatitis B Surface Antigen in Transgenic Panax ginseng C. A. Meyer Callus

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Chemical Research in Chinese Universities 2008年第1期24卷 75-79页

作者： GAO Zheng-lun SHENG Jun HAO Shu-mei liu Dan liu xiao-yu JI Hai-bin LI Juan ZHANG Xian-ping College of Life Science Jilin University Changchun 130012 P R. China Changchun Institute of Biological Product Changchun 130062 P. R China Changchun University of Science and Technology Changchun 130022 P. R. China Jilin Institute for Food and Drug Control Changchun 130062 P R. China

The 5＇-nontranslated leader（omega sequence） of Tobacco mosaic virus（TMV） was used as a translational enhancer sequence in the expression of the hepatitis B surface antigen（HBsAg） gene in transgenic ginseng callus cultures. The adr subtype HBsAg gene was placed under the control of the Cauliflower mosaic virus（CaMV） 35S promoter linking to the TMV leader sequence. The antisense omega sequence was used in a control construct. The resulting constructs cloned in the binary vector pBI121 were used to transform the ginseng callus tissue via the Agrobacterium-mediated procedure. The integration and expression of the HBsAg gene were evaluated by PCR and western blot, respectively. Enzyme-linked immunoassays（ELISA） using a monoclonal antibody directed against human serum-derived HBsAg revealed a three to four-fold enhanced expression of HBsAg in ginseng cells conferred by the TMV omega element.

关键词： Translational enhancer Omega sequence Hepatitis B surface antigen Ginseng callus

Probing the dynamic thermodynamic resolution and biological activity of Cu(Ⅱ) and Pd(Ⅱ) complexes with Schiff base ligand derived from proline

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Chinese Chemical Letters 2024年第4期35卷 99-105页

作者： Tao yu Vadim A.Soloshonok Zhekai xiao Hong liu Jiang Wang State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China School of Pharmacy University of Chinese Academy of SciencesBeijing 100049China Department of Organic Chemistry Ⅰ Faculty of ChemistryUniversity of the Basque Country UPV/EHUSan Sebastian 20018Spain IKERBASQUE Basque Foundation for ScienceBilbao 48013Spain School of Pharmaceutical Science and Technology Hangzhou Institute for Advanced StudyUCASHangzhou 310024China Lingang Laboratory Shanghai 200031China

Schiff base metal complexes are of great importance in pharmaceutical science owing to their unique chemical properties, which enable them to exhibit diverse biological activities such as anti-bacterial,anti-oxidant, anti-inflammatory, and anti-tumor properties. Furthermore, Schiff base metal complexes can serve as reagents and catalysts in chemical reactions. This review aims to provide an overview of our recently published studies on Cu(Ⅱ) and Pd(Ⅱ) complexes derived from proline Schiff base ligands. We also discuss the potential applications of these metal complexes in the fields of antibacterial and chiral resolution.

关键词： Schiff bases Biological activity Tailor-made amino acids Asymmetric synthesis Chiral tridentate ligands Square-planar Cu(Ⅱ)-complexes Square-planar Pd(Ⅱ)-complexes

Development of study on the dynamic characteristics of deep water mooring system

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Journal of Marine Science and Application 2007年第3期6卷 17-23页

作者： TANG You-gang ZHANG Su-xia ZHANG Ruo-yu liu Hai-xiao School of Civil Engineering Tianjin University Tianiin 300072 China

To meet the needs of those exploiting deepwater resources, TLP and SPAR platforms are used in some areas and are considered excellent platforms in deep water. However, many problems remain to be resolved. The design of mooring systems is a key issue for deep water platforms. Environmental loads in deep water effect the physical characteristics of mooring line materials. The configuration and analysis of mooring systems involve nonlinearity due to this fluid-solid coupling, nonlinear hydrodynamic forces, and their effects on stability of motion. In this paper, some pivotal theories and technical questions are presented, including modeling of mooring lines, the theory and method of coupled dynamics analysis on the mooring system, and the development of methodologies for the study of nonlinear dynamics of mooring systems. Further study on mooring systems in deep water are recommended based on current knowledge, particularly dynamic parameters of different materials and cable configuration, interactions between seabed and cable, mechanisms of mooring system response induced by taut/slack mooring cables, discontinuous stiffness due to system materials, mooring construction, and motion instability, etc.

关键词： mooring in the deep water platform in the deep water dynamic response stability of motion

雇佣关系的变迁：员工性别、价值观及工作经历的影响模式

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系统工程理论与实践 2008年第5期28卷 29-36,76页

作者：刘小禹刘军中国人民大学劳动人事学院北京100872 中国人民大学商学院北京100872

目的是考察员工入职前后雇佣关系的"质变",检验了员工性别、价值观及其在组织中的工作经历对雇佣关系感知变迁的影响.采用追踪研究设计,跨时三年,实证研究结果表明:持有个人主义价值观的员工在入职前更容易期待短期的雇佣关系;相反,高... 详细信息

目的是考察员工入职前后雇佣关系的"质变",检验了员工性别、价值观及其在组织中的工作经历对雇佣关系感知变迁的影响.采用追踪研究设计,跨时三年,实证研究结果表明:持有个人主义价值观的员工在入职前更容易期待短期的雇佣关系;相反,高传统的员工则倾向于期待长期的雇佣关系;相对于女性员工,男性员工更可能因为组织给予的工作奖赏和组织支持而向长期型雇佣关系转变;入职两年后,男性员工更愿意与组织建立长期的雇佣关系;传统的员工更可能因组织支持而向长期雇佣关系转变.

关键词：雇佣关系价值观组织支持工作奖赏

Large-inductance superconducting microstrip photon detector enabling 10 photon-number resolution

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Advanced Photonics 2024年第1期6卷 96-105页

作者： Ling-Dong Kong Tian-Zhu Zhang xiao-yu liu Hao Li Zhen Wang xiao-Ming Xie Li-Xing You Chinese Academy of Sciences(CAS) Shanghai Institute of Microsystem and Information TechnologyNational Key Laboratory of Materials for Integrated CircuitsShanghaiChina CAS Center for Excellence in Superconducting Electronics ShanghaiChina University of Chinese Academy of Sciences Center of Materials Science and Optoelectronics EngineeringBeijingChina

Efficient and precise photon-number-resolving detectors are essential for optical quantum information *** this,very few detectors have been able to distinguish photon numbers with both high fidelity and a large dynamic range,all while maintaining high speed and high timing *** nanostrip-based detectors excel at counting single photons efficiently and rapidly,but face challenges in balancing dynamic range and ***,we have pioneered the demonstration of 10 true photon-number resolution using a superconducting microstrip detector,with readout fidelity reaching an impressive 98%and 90%for 4-photon and 6-photon events,***,our proposed dual-channel timing setup drastically reduces the amount of data acquisition by 3 orders of magnitude,allowing for real-time photon-number *** then demonstrate the utility of our scheme by implementing a quantum random-number generator based on sampling the parity of a coherent state,which guarantees inherent unbiasedness,robustness against experimental imperfections and environmental noise,as well as invulnerability to *** solution boasts high fidelity,a large dynamic range,and real-time characterization for photon-number resolution and simplicity with respect to device structure,fabrication,and readout,which may provide a promising avenue towards optical quantum information science.

关键词： superconducting microstrips single-photon detector photon-number resolution quantum random number