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Effect of hot isostatic pressing processing parameters on microstructure and properties of Ti60 high temperature titanium alloy

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China Foundry 2023年第1期20卷 49-56页

作者： tian-yu Liu Kun Shi Jun Zhao Shi-bing Liu You-wei Zhang Hong-yu Liu tian-yi Liu Xiao-ming Chen Xin-min Mei Shenyang Research Institute of Foundry Co. Ltd.Shenyang 110022China State Key Laboratory of Light Alloy Casting Technology for High-end Equipment Shenyang 110022China

Hot isostatic pressing parameters are critical to Ti60 high temperature titanium alloy castings which have wide application perspective in *** order to obtain optimal processing parameters,the effects of hot isostatic pressing parameters on defects,composition uniformity,microstructure and mechanical properties of Ti60 cast high temperature titanium alloy were investigated in *** show that increasing temperature and pressure of hot isostatic pressing can reduce defects,especially,the internal defects are substantially eliminated when the temperature exceeds 920℃or the pressure exceeds 125 *** higher temperature and pressure can improve the microstructure ***,the higher pressure can promote the composition *** the temperature increases from 880℃to 960℃,α-laths are *** with increasing pressure,the grain size of prior-βphase,the widths ofα-laths andα-colony are *** tensile strength of Ti60 alloy is 949 MPa,yield strength is 827 MPa,and the elongation is 11%when the hot isostatic pressing parameters are 960℃/125 MPa/2 h,which exhibits the best match between the strength and plasticity.

关键词： hot isostatic pressing processing parameters Ti60 titanium alloy defects composition uniformity microstructure mechanical properties

Coordinated control of an intelligent wheelchair based on a brain-computer interface and speech recognition

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第10期15卷 832-838页

作者： Hong-tao WANG yuan-qing LI tian-you yu School of Information Engineering Wuyi University School of Automation Science and Engineering South China University of Technology Engineering Research Center for Massive Biometric Information Processing

An intelligent wheelchair is devised, which is controlled by a coordinated mechanism based on a brain-computer interface(BCI) and speech recognition. By performing appropriate activities, users can navigate the wheelchair with four steering behaviors(start, stop, turn left, and turn right). Five healthy subjects participated in an indoor experiment. The results demonstrate the efficiency of the coordinated control mechanism with satisfactory path and time optimality ratios, and show that speech recognition is a fast and accurate supplement for BCI-based control systems. The proposed intelligent wheelchair is especially suitable for patients suffering from paralysis(especially those with aphasia) who can learn to pronounce only a single sound(e.g., ‘ah').

关键词： Brain-computer interface Speech recognition Coordinated control Intelligent wheelchair

Branched-chain amino acids supplementation has beneficial effects on the progression of liver cirrhosis:A meta-analysis

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World Journal of Clinical Cases 2022年第30期10卷 10984-10996页

作者： Jia-yu Du Liu Shu yu-tian Zhou Li Zhang School of Clinical Medicine Chengdu Medical CollegeChengdu 610000Sichuan ProvinceChina Department of Neuroscience College of Veterinary Medicine and Life SciencesCity University of Hong KongHong KongChina Department of Geriatrics Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610000Sichuan ProvinceChina Department of Geriatrics Sichuan Academy of Medical Sciences&Sichuan Provincial People’s HospitalChengdu 610072Sichuan ProvinceChina

BACKGROUND Liver cirrhosis(LC)is currently the 11^(th) most common cause of death and 15^(th) cause of morbidity *** treatment of LC is mainly aimed at etiological intervention,lifestyle intervention,prevention and treatment of complications and nutritional *** treatment of LC mainly includes increasing dietary intake,food intake time and branched-chain amino acids(BCAAs).Despite the recommendation of BCAAs in some guidelines,adverse effects have been reported in studies so the efficacy and safety of BCAAs remain ***,BCAAs have been widely used in chronic liver disease,while the summary of the effect of BCAAs on long-term prognosis is *** To determine the effects of BCAAs in patients with *** The PubMed,Cochrane Library,Embase and Web of Science databases were *** retrieval deadline was 1 October 2021 and there were no language restrictions set in the *** study was performed in strict accordance with the inclusion and exclusion *** studies were finally *** primary outcome was complications of *** secondary outcomes were nutritional status and liver *** meta-analysis used the Review Manager,version 5 statistical package(Cochrane Collaboration,Oxford,England)for *** The analysis included nine studies that consisted of 1080 patients(554 in the BCAA groups and526 in the control groups).The nine studies were randomized control trials(RCTs).The quality of the studies was assessed using the risk of bias method recommended by the Cochrane *** reduced the rate of complications in LC patients[Risk ratio:0.70,95%confidence interval(CI):0.56-0.88,P=0.002]and improved patients’albumin levels[std mean difference SMD:0.26,95%CI:0.12-0.40,P=0.0002].Meanwhile,BCAAs significantly ameliorated the levels of alanine transaminase(SMD:-2.03,95%CI:-2.52 to-1.53,P<0.00001)and aspartate aminotransferase(SMD:-1.8,95%CI:-2.14 to-1.46,P<0.00001).Meanwhile,gl

关键词： Liver cirrhosis Branched-chain amino acids Complications Nutrition Liver function Glucose

Four Complexes of Mn(Ⅱ),Co(Ⅱ),Ni(Ⅱ)and Cu(Ⅱ)Based on 2-Morpholine-4-yl-4,6-di-pyrazol-1-yl-1,3,5-triazine

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Chinese Journal of Structural Chemistry 2021年第6期40卷 729-738,684页

作者： tian Wen-yu CHU Jin-Feng State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Three azide bridged complexes,namely,[Mn_(2)L_(2)(N_(3))_(4)(H_(2)O)_(2)](1),[Co_(2)L_(2)(N_(3))_(4)]·(H_(2)O)_(3)(2)and[Ni_(2)L_(2)(N_(3))_(3)(H_(2)O)]N_(3)·(H_(2)O)4(3)(L=2-morpholine-4-yl-4,6-di-pyrazol-1-yl-1,3,5-triazine),were synthesized by the reaction of L ligand,sodium azide with Mn(Ⅱ),Co(Ⅱ)and Ni(Ⅱ)*** copper(Ⅱ)chloride combined with thiocyanate and L ligand to form a mononuclear complex[CuL(CH3OH)(SCN)(NCS)](4).Complexes 1~4 were characterized by IR,elemental analysis and X-ray crystallographic *** was worth noting that two Mn(Ⅱ)atoms were connected by the end-to-end mode in 1,while Co(Ⅱ)and Ni(Ⅱ)atoms were connected by the end-on mode in 2 and *** complex 4,the central copper atom was coordinated with a sulfur atom and a nitrogen atom of the two thiocyanate ligands,*** bonds,π-πstacking interactions,thermogravimetric analysis and fluorescence properties of 1~4 were studied.

关键词： azide bridged complexes supramolecular crystal structure thiocyanate

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In the Atmosphere and Oceanic Fluids:Scaling Transformations,Bilinear Forms,Bäcklund Transformations and Solitons for A Generalized Variable-Coefficient Korteweg-de Vries-Modified Korteweg-de Vries Equation

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China Ocean Engineering 2021年第4期35卷 518-530页

作者： GAO Xin-yi GUO Yong-jiang SHAN Wen-rui ZHOU tian-yu WANG Meng YANGDan-yu State Key Laboratory of Information Photonics and Optical Communications and School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

The atmosphere is an evolutionary agent essential to the shaping of a planet,while in oceanic science and daily life,liquids are commonly *** this paper,we investigate a generalized variable-coefficient Korteweg-de Vriesmodified Korteweg-de Vries equation for the atmosphere,oceanic fluids and *** symbolic computation,beginning with a presumption,we work out certain scaling transformations,bilinear forms through the binary Bell polynomials and our scaling transformations,N solitons(with N being a positive integer)via the aforementioned bilinear forms and bilinear auto-Bäcklund transformations through the Hirota method with some *** addition,Painlevé-type auto-Bäcklund transformations with some solitons are symbolically computed *** dependences and constraints on the variable/constant coefficients are discussed,while those coefficients correspond to the quadratic-nonlinear,cubic-nonlinear,dispersive,dissipative and line-damping effects in the atmosphere,oceanic fluids and plasmas.

关键词： atmosphere oceanic fluids plasmas generalized variable-coefficient Korteweg-de Vries-modified Korteweg-de Vries equation scaling transformations bilinear forms N solitons auto-Bäcklund transformations

Hydrogen Bond Cooperative Effect in Single Cage Water Clusters

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Chinese Journal of Structural Chemistry 2020年第7期39卷 1213-1225页

作者： HU Xiao-Min yu yu-tian CHEN Si-yu LEI Ming PU Min YANG Zuo-Yin Department of Physical Chemistry College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China

In this paper,DFT method was used to study the relative stability of hydrogen bonding networks of numerous 512,51262 and 435663 water cluster *** we introduced an optimized six-digit definition to characterize diverse sub-grouped hydrogen bonds to consider the cooperative effect of the nearest and nextnearest neighbor water *** are totally 74 kinds of sub-grouped hydrogen bonds in cage hydrate clusters,and these energies can be obtained by iterative *** improvement effectively explains some regularity contained in hydrogen bonding cooperative *** general,donor or acceptor fragment sharing identical value of three independent digits usually performs poor cooperative effect,indicating that the existence of those same-digital-array fragments is the necessary condition to judge poor cooperative *** versa,the existence of different-digital-array is also the necessary condition to judge strong cooperative effect.

关键词： sub-grouped hydrogen bond cooperative effect water cluster nearest neighbor next-nearest neighbor

Quasicrystal dissolution and performance of isothermally heat-treated Mg–Zn–Y alloy

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Rare Metals 2015年第7期34卷 452-456页

作者： Di-Qing Wan Xian Luo Ya-Juan Liu tian yu Key Laboratory of Ministry of Education for Conveyance and Equipment East China Jiaotong University State Key Laboratory of Solidification Processing Northwestern Polytechnical University School of Materials Science Northwestern Polytechnical University

Conventional casting method was employed to prepare Mg–Zn–Y alloy only with a-Mg+I-phase; however, the grain size of quasicrystal is quite large in the ascast ***, isothermal treatment was applied to refine the quasicrystal *** result shows that after the Mg–Zn–Y alloy was isothermally treated at 500 °C for several hours, the coarse quasicrystal can be gradually dissolved and thus ***, the dissolving processes of quasicrystal are slow first and then accelerate;after isothermally treated with 8 h at 500 °C, the quasicrystal is almost completely dissolved into the matrix only with 1–5 lm tiny quasicrystals *** of quasicrystal can markedly reduce the wear resistance, but increase the corrosion resistance.

关键词： Magnesium alloy Quasicrystal Isothermal treatment

Composition and distribution of ground-dwelling beetles among oak fragments and surrounding pine plantations in a temperate forest of North China

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Insect Science 2014年第1期21卷 114-124页

作者： Xiao-Dong yu tian-Hong Luo Hong-Zhang Zhou Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Beijing China

In this study, we compared ground-dwelling beetle assemblages （Coleoptera） from a range of different oak fragments and surrounding conifer plantations to evaluate effects of forest size and surrounding matrix habitat in a temperate forest of north China. During 2000, beetles were sampled via pitfall traps within two large oak fragments （ca. 2.0-4.0 ha）, two small oak fragments （ca. 0.2-0.4 ha） and two surrounding matrices dom- inated by pine plantations （〉4 ha） in two sites of different aspects. Overall, no significantly negative effects from forest patch size and the surrounding matrix habitat were detected in total species number and abundance of ground-dwelling beetles. However, compared with small oak patches or pine plantations, more species were associated with an affinity for at least one large oak patch of the two aspects. Multivariate regression trees showed that the habitat type better determined the beetle assemblage structure than patch size and aspect, indicating a strong impact of the surrounding matrix. Linear mixed models indicated that species richness and abundance of all ground-dwelling beetles or beetle families showed different responses to the selected environmental variables. Our results suggest that more disturbed sites are significantly poorer in oak forest specialists, which are usually more abundant in large oak fragments and decrease in abundance or disappear in small fragments and surrounding matrix habitats. Thus, it is necessary to preserve a minimum size of forest patch to create conditions characteristic for forest interior, rather than the more difficult task of increasing habitat connectivity.

关键词： forest patch size fragmentation ground-dwelling beetles North China,surrounding matrix habitat temperate forest

Investigation of the possible source for the solar energetic particle event on 2017 September 10

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Research in Astronomy and Astrophysics 2018年第7期18卷 1-10页

作者： Ming-Xian Zhao Gui-Ming Le yu-tian Chi Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological AdministrationBeijing 100081China School of Computer Science Anhui University of TechnologyMa'anshan 243032China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China

According to the solar proton data observed by Geostationary Operational Environmental Satellites （GOES）, ground-based neutron monitors on Earth and near-relativistic electron data measured by the ACE spacecraft, the onset times of protons with different energies and near-relativistic electrons have been estimated and compared with the time of solar soft and hard X-ray and radio burst data. The results show that first arriving relativistic and non-relativistic protons and electrons may have been accelerated by the concurrent flare. The results also suggest that release times of protons with different energies may be different, and the protons with lower energy may have been released earlier than those with higher energy. Some protons accelerated by concurrent flares may be further accelerated by the shock driven by the associated CME.

关键词： Sun coronal mass ejections (CMEs) - Sun flares - Sun particle emission