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High-Superelasticity NiTi Shape Memory Alloy by Directed Energy Deposition-Arc and Solution Heat Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 132-144页

作者： junyi Ma Lin Yu qing Yang Jie Liu Lei Yang State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430070China School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan430074China

Directed energy deposition-arc(DED-Arc)technology has the advantages of simple equipment,low manufacturing cost and high deposition rate,while the use of DED-Arc has problems of microstructure inhomogeneity,position dependence of macroscopic mechanical properties and ***,it is necessary to carry out a subsequent heat treatment to improve its microstructure uniformity,mechanical properties and *** this investigation,the DED-Arc 15-layer NiTi alloy thin-walled parts with the solution treatment at different process parameters were studied to analyze the effects of solution heat treatment on microstructure,phase composition,phase transformation,microhardness,tensile and *** temperature range of solution treatment is 800-1050℃,and the treatment time range is 1-5.5 *** results show that after solution treatment at 800℃/1 h,the content of precipitated phase decreases,the grain is refined,the microhardness increases,and the mechanical properties in the 0°direction are *** strain recovery rate after 10 tensile cycles has increased from 37.13%(as-built)to 49.25%(solid solution treatment).This research provides an effective post treatment method for high-performance DED-Arc NiTi shape memory alloys.

关键词： Directed energy deposition-arc(DED-Arc) Cold metal transfer(CMT) NiTi shape memory alloys Microstructure Phase transformation Solution heat treatment

Study on the Adaptability of Etherification Feedstock to Reactor Type

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China Petroleum Processing & Petrochemical Technology 2016年第2期18卷 57-62页

作者： Mao junyi Yuan qing Wang Lei Huang Tao SINOPEC Research Institute of Petroleum Processing Beijing 100083

A reactive C5 olefins and methanol etherification kinetic model based on E-R mechanism was established and three different types of reactors including the adiabatic fixed-bed liquid reactor, the external loop reactor and the mixedphase reactor were constructed by Aspen Plus. The adaptability of reactive C5 olefins to these reactors was studied and simulated using various gasoline fractions with different olefins content. After the theoretical model was validated by the experimental data of the etherification of three C5 light cut fractions from different gasoline sources in different reactors, the simulated isoamylene conversion with reactive C5 olefin contents increasing from 10% to 60% was studied in the three different types of reactors for etherification with methanol, respectively. Test results show that there is an obvious adaptability of the feedstock composition to the reactor type to achieve a high conversion.

关键词： etherification reactor feedstock adaptability

Tu-Xian Decoction ameliorates diabetic cognitive impairment by inhibiting DAPK-1

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Chinese Journal of Natural Medicines 2023年第12期21卷 950-960页

作者： WANG Danyang YAN Bin WANG An SUN qing PANG junyi CUI Yangming TIAN Guoqing Department of Traditional Chinese Medicine Peking Union Medical College HospitalBeijing 100730China Chinese Academy of Mediucal Sciences&Peking Union Medical College Beijing 100730China Department of Pathology Peking Union Medical College HospitalState Key Laboratory of Complex Severe and Rare DiseaseMolecular Pathology Research CenterBeijing 100730China Animal Research Laboratory Platform Peking Union Medical College Hospitalthe National Science and Technology Key Infrastructure on Translational MedicineBeijing 100730China

Tu-Xian decoction(TXD),a traditional Chinese medicine(TCM)formula,has been frequently administered to manage diabetic cognitive impairment(DCI).Despite its widespread use,the mechanisms underlying TXD’s protective effects on DCI have yet to be fully *** a significant regulator in neurodegenerative conditions,death-associated protein kinase-1(DAPK-1)serves as a focus for understanding the action of *** study was designed to whether TXD mediates its beneficial outcomes by inhibiting *** this end,a diabetic model was established using Sprague-Dawley(SD)rats through a high-fat,high-sugar(HFHS)diet regimen,followed by streptozotocin(STZ)*** experimental cohort was stratified into six groups:Control,Diabetic,TC-DAPK6,high-dose TXD,medium-dose TXD,and low-dose TXD *** a 12-week treatment period,various assessments—including blood glucose levels,body weight measurements,Morris water maze(MWM)testing for cognitive function,brain magnetic resonance imaging(MRI),and histological analyses using hematoxylin-eosin(H&E),and Nissl staining—were *** expression in the hippocampus was quantified through Western blotting *** results revealed that TXD significantly improved spatial learning and memory abilities,and preserved hippocampal structure in diabetic ***,TXD administration led to a down-regulation of proteins indicative of neurological damage and suppressed DAPK-1 activity within the hippocampal *** results underscore TXD's potential in mitigating DCI via DAPK-1 inhibition,positioning it as a viable therapeutic candidate for addressing this *** investigation into TXD's molecular mechanisms may elucidate new pathways for the treatment of DCI.

关键词： Tu-Xian decoction Traditional Chinese medicine Diabetes complications Diabetic cognitive impairment Death associated protein kinase-1

The impact of COVID-19 on stock markets

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Economic and Political Studies 2020年第3期8卷 275-288页

作者： qing He junyi Liu Sizhu Wang Jishuang Yu China Financial Policy Research Centre and School of Finance Renmin University of ChinaBeijingP.R.China Department of Economics Soka University of AmericaAliso ViejoUSA School of Finance Renmin University of ChinaBeijingP.R.China

This paper attempts to explore the direct effects and spill-overs of COVID-19 on stock *** conventional t-tests and nonparametric Mann–Whitney tests,we empirically analyse daily return data from stock markets in the People’s Republic of China,Italy,South Korea,France,Spain,Germany,Japan and the United States of *** empirical results show that(i)COVID-19 has a negative but short-term impact on stock markets of affected countries and that(ii)the impact of COVID-19 on stock markets has bidirectional spill-over effects between Asian countries and European and American ***,there is no evidence that COVID-19 negatively affects these countries’stock markets more than it does the global *** findings contribute to the research on economic impact of the pandemic by providing empirical evidence that COVID-19 has spill-over effects on stock markets of other *** results also provide a basis for assessing trends in international stock markets when the situation is alleviated worldwide.

关键词： COVID-19 coronavirus disease stock markets spillover effect

Simplified unscented particle filter for nonlinear/non-Gaussian Bayesian estimation

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Journal of Systems Engineering and Electronics 2013年第3期24卷 537-544页

作者： junyi Zuo Yingna Jia Quanxue Gao School of Aeronautics Northwestern Polytechnical University Aviation Equipment Research Institute Qing'an Group Corporation Limited State Key Laboratory of Integrated Service Networks Xidian University

Particle filters have been widely used in nonlinear/non- Gaussian Bayesian state estimation problems. However, efficient distribution of the limited number of particles （n state space remains a critical issue in designing a particle filter. A simplified unscented particle filter （SUPF） is presented, where particles are drawn partly from the transition prior density （TPD） and partly from the Gaussian approximate posterior density （GAPD） obtained by a unscented Kalman filter. The ratio of the number of particles drawn from TPD to the number of particles drawn from GAPD is adaptively determined by the maximum likelihood ratio （MLR）. The MLR is defined to measure how well the particles, drawn from the TPD, match the likelihood model. It is shown that the particle set generated by this sampling strategy is more close to the significant region in state space and tends to yield more accurate results. Simulation results demonstrate that the versatility and es- timation accuracy of SUPF exceed that of standard particle filter, extended Kalman particle filter and unscented particle filter.

关键词： nonlinear filtering particle filter unscented Kalman filter importance density function.

Comparison of the water quality of the surface microlayer and subsurface water in the Guangzhou segment of the Pearl River, China

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Journal of Geographical Sciences 2014年第3期24卷 475-491页

作者： LIU qing HU Xiaojuan JIANG Jiangluan ZHANG junyi WU Zhihui YANG Yufeng Institute of Hydrobiology Jinan University Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institutes Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering Ministry of Education Guangzhou 510632 China Shenzhen Academy of Environmental Sciences Shenzhen 518002 Guangdong China Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization of Ministry of Agriculture Key Laboratory of Fishery Ecology and Environment of Guangdong Province South China Sea Fisheries Institute Chinese Academy of Fishery Sciences Guangzhou 510300 China Beijing Normal University-Hong Kong Baptist University Untied International College Zhuhai 519000 Guangdong China

The water quality in the surface microlayer （SML） and subsurface water （SSW） in the Guangzhou segment of Pearl River, a eutrophic urban river section in China, were ana- lyzed. The spatial and temporal dynamics of nutrient concentrations, heavy metals and bac- teria were examined from two sampling sites in monthly samples throughout 2010. The mean concentrations of total nitrogen, ammonia, nitrate and nitrite were higher than 7.0 mg/L, 3.1 mg/L, 1.1 mg/L and 0.3 mg/L, while total phosphorus and orthophosphate were 0.5 mg/L and 0.1 mg/L, respectively. These results indicated that the water quality was rich in minerals and eutrophic. The mean concentrations of Mn and Fe were higher than 0.013 mg/L; and Ni, Cr and Pb were higher than 0.001 mg/L. The mean concentrations were in the order of Mn 〉Fe 〉 Ni 〉 Pb 〉 Cr. The concentrations of heavy metals in the Guangzhou segment were lower than the limit of the surface water quality standards in China and the World Health Organization （WHO）, but higher than the median values in the world＇s freshwater. The density of bacteria ranged from 3.30×10^5 to 5.23×10^6 cells/mL, and the amount of cultivable heterotrophic bac-teria ranged from 1.30×10^3 to 1.89×10^6 cfu/mL. Fecal coliform levels were beyond the V class of China water quality standard. The SML was enriched in nutrients, heavy metals and bac- teria, with the maximum enrichment factor of 3.84 for nutrients, 8.00 for heavy metals, and 3.04 for bacteria, suggesting that the water quality of the SML of the Guangzhou segment of the Pearl River was more serious than in the SSW.

关键词： surface microlayer nutrients heavy metal microbes Guangzhou segment Pearl River

A novel ferroelectric based on quinuclidine derivatives

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Chinese Chemical Letters 2020年第6期31卷 1686-1689页

作者： Siyu Deng junyi Li Xiang Chen Yunlong Hou Lizhuang Chen School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

The compound[(CH3)2 CH-C3 H17 N][CoBr4](1)based on quinuclidine derivatives was achieved by the solution synthetic method and characterized by elemental analysis,infrared spectroscopy,single-crystal X-ray structural analysis and dielectric measurement,***-temperature single-crystal X-ray diffraction suggested that the compound unde rwent the phase transition from the space group C2/c to *** polarization curve was measured using the Sawyer-Tower *** structural phase transitions of 1 was ascribed to the distortion of a[(CH3)2 CH-C3 H17N]2+cation from this inorganicorganic hybrid material[(CH3)2 CH-C3 H17N][CoBr4].The strong change in dielectric anomalies makes compound 1 a suitable candidate for promising switchable dielectric *** work represents a feasible strategy thought for the targeted harvesting of low temperature ferroelectrics.

关键词： Ferroelectric Quinuclidine Phase transition Polarization Dielectric

非光滑凸问题投影型对偶平均优化方法的个体收敛性

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模式识别与人工智能 2021年第1期34卷 25-32页

作者：曲军谊鲍蕾陶卿中国人民解放军陆军炮兵防空兵学院信息工程系合肥230031

对于一般凸问题,对偶平均方法的收敛性分析需要在对偶空间进行转换,难以得到个体收敛性结果.对此,文中首先给出对偶平均方法的简单收敛性分析,证明对偶平均方法具有与梯度下降法相同的最优个体收敛速率Ο(ln t√t).不同于梯度下降法,讨... 详细信息

对于一般凸问题,对偶平均方法的收敛性分析需要在对偶空间进行转换,难以得到个体收敛性结果.对此,文中首先给出对偶平均方法的简单收敛性分析,证明对偶平均方法具有与梯度下降法相同的最优个体收敛速率Ο(ln t√t).不同于梯度下降法,讨论2种典型的步长策略,验证对偶平均方法在个体收敛分析中具有步长策略灵活的特性.进一步,将个体收敛结果推广至随机形式,确保对偶平均方法可有效处理大规模机器学习问题.最后,在L1范数约束的hinge损失问题上验证理论分析的正确性.

关键词：对偶平均个体收敛速率稀疏性非光滑

Tunable spin textures in polar antiferromagnetic hybrid organic–inorganic perovskites by electric and magnetic fields

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npj Computational Materials 2020年第1期6卷 714-722页

作者： Feng Lou Teng Gu junyi Ji Junsheng Feng Hongjun Xiang Alessandro Stroppa Key Laboratory of Computational Physical Sciences(Ministry of Education) State Key Laboratory of Surface Physicsand Department of PhysicsFudan UniversityShanghai 200433China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China School of Physics and Materials Engineering Hefei Normal UniversityHefei 230601China Shanghai Qizhi Institution Shanghai 200433China CNR-SPIN c/o Department of Physical and Chemical SciencesUniversity of L’Aquila67100 Coppito(AQ)L’AquilaItaly

The hybrid organic–inorganic perovskites(HOIPs)have attracted much attention for their potential applications as novel optoelectronic ***,the Rashba band splitting,together with specific spin orientations in k-space(i.e.,spin texture),has been found to be relevant for the optoelectronic *** this work,by using first-principles calculations and symmetry analysis,we study the electric polarization,magnetism.

关键词： inorganic textures optoelectronic