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JAMA N：卒中二级预防的血压目标应小于130/80 mm Hg?

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中国卒中杂志 2020年第2期15卷 169-170页

作者：杨中华 KITAGAWA K yAMAMOTO Y.ARIMA H 首都医科大学附属北京天坛医院神经病学中心脑血管病中心神经重症医学科北京100070 不详

2010年,全世界首次卒中的绝对人数为1690万,卒中相关死亡人数为590万,因此,卒中的一级和二级预防应优先考虑。血压升高是卒中最相关、最常见的危险因素,降压治疗是卒中一级和二级预防最有效的方法。在心血管事件(包括卒中)的一级预防试... 详细信息

2010年,全世界首次卒中的绝对人数为1690万,卒中相关死亡人数为590万,因此,卒中的一级和二级预防应优先考虑。血压升高是卒中最相关、最常见的危险因素,降压治疗是卒中一级和二级预防最有效的方法。在心血管事件(包括卒中)的一级预防试验中,高血压患者血压控制越低,卒中预防效果越好,并且有研究发现血压y,PROGRESS)显示,无论是否存在高血压,卒中慢性期降压治疗能够降低复发性卒中风险。

关键词：二级预防培哚普利降压治疗复发性卒中 PROGRESS 心血管事件首次卒中死亡人数

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基于深度学习的无误配伪影脑血管造影生成模型

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国际医学放射学杂志 2021年第4期44卷 484-485页

作者： D.Ueda y.Katayama A.yamamoto T.Ichinose H.arima y.Watanabe 张雅欣

摘要数字减影血管造影(DSA)是从动态血管造影中减去蒙片图像生成的减影图像,但病人移动引起的误配伪影可致 DSA 图像模糊,从而妨碍操作。目的本研究旨在训练并

关键词：深度学习生成模型

WONCA研究论文摘要汇编——急性颅内出血后血压变异性及转归:INTERACT2研究的析因分析,一项随机对照试验

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中国全科医学 2014年第21期17卷 2461-2461页

作者： Manning L Hirakawa Y.ARIMA H 周淑新中国石油天然气集团公司中心医院

背景高血压是急性脑卒中的预后因子，血压变异性或许可以独立预测脑卒中的转归。我们评估了血压变异性对INTERACT2参试者脑卒中预后的预测价值， INTERACT2是一项开放标签随机对照试验。方法 INTERACT2将患有自发性颅内出血（ICH）、高... 详细信息

背景高血压是急性脑卒中的预后因子，血压变异性或许可以独立预测脑卒中的转归。我们评估了血压变异性对INTERACT2参试者脑卒中预后的预测价值， INTERACT2是一项开放标签随机对照试验。方法 INTERACT2将患有自发性颅内出血（ICH）、高收缩压（150～220 mm Hg）、对早期降压强化疗法无明确适应证或禁忌证的2839例成人纳入研究。将患者随机分为强化治疗组（经静脉给药，1 h内目标收缩压降至＜140 mm Hg ）和指南推荐的治疗组（ ICH 后6 h 内，目标收缩压降至＜180 mm Hg）。主要转归为死亡或90 d内发生生活大部分无法自理（改良Rankin量表评分≥3分）；次要转归为90 d内改良Rankin量表评分发生顺序移动，调查员在评分时并不知晓患者接受了哪种治疗。根据标准定义血压变异性：在发病头24 h （超急性期）进行5次测量，在发病后2～7 d （急性期）进行不少于12次的测量。采用比例优势逻辑回归模型评价血压变异性与转归之间的关联。血压变异性关键指标为收缩压的标准差，按五分位数加以分类。发现研究者对2645例（93.2％）处于超急性期的患者和2347例（82.7％）处于急性期的患者进行了调查。将两个治疗组的数据一起分析，在超急性期〔最高五分位数校正OR＝1.41，95％CI （1.05，1.90）； P＝0.0167〕和急性期〔最高五分位数校正OR＝1.57，95％CI （1.14，2.17）； P＝0.0124〕，收缩压的标准差与主要转归均呈线性相关。对转归最强的预测指标为超急性期最高收缩压和急性期收缩压的标准差为结果的最强预示因子。对次要转归进行分析，得到的结果与以上结果相似〔超急性期最高五分位数，校正OR＝1.43，95％CI （1.14，1.80）； P＝0.0014；急性期OR＝1.46，95％CI （1.13，1.88）； P＝0.0044〕。解释收缩压变异性似乎可预测急性颅内出血患者的不良转归。早期治疗将收缩压降至140 mm Hg以下获得的收益，可通过平稳并持续血压控制进行强化，避免出现收缩压峰值尤为重要。

关键词：急性颅内出血随机对照试验血压变异性不良转归 WONCA 论文摘要急性脑卒中超急性期

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The roles of polymer-graphene interface and contact resistance among nanosheets in the effective conductivity of nanocomposites

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 1941-1956页

作者： y.ZARE K.y.RHEE Department of Mechanical Engineering(BK21 Four) College of EngineeringKyung Hee UniversityYongin 17104Republic of Korea

The effective conductivity of graphene-based nanocomposites is suggested by the characteristics of polymer-filler interfacial areas as well as the contact resistance between the neighboring nanosheets.The interfacial properties are expressed by the effective levels of the inverse aspect ratio and the filler volume fraction.Moreover,the resistances of components in the contact regions are used to define the contact resistance,which inversely affects the effective conductivity.The obtained model is utilized to predict the effective conductivity for some examples.The discrepancy of the effective conductivity at various ranks of all factors is clarified.The interfacial conductivity directly controls the effective conductivity,while the filler conductivity plays a dissimilar role in the effective conductivity,due to the incomplete interfacial adhesion.A high operative conductivity is also achieved by small contact distances and high interfacial properties.Additionally,big contact diameters and little tunnel resistivity decrease the contact resistance,thus enhancing the effective conductivity.

关键词： polymer nanocomposite operative conductivity graphene interfacial property contact region

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Enhanced pitting corrosion resistance of a Zr-based metallic glass by ultraviolet light irradiation

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Journal of Iron and Steel Research(International) 2023年第8期30卷 1642-1649页

作者： Z.Chen D.P.Wang S.Wang y.X.Geng y.X.Guo y.C.Wu Z.G.Liu y.y.Zhang y.X.Wang School of Materials Science and Engineering Jiangsu University of Science and Technology.Zhenjiang 212003JiangsuChina School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina

The influence of ultraviolet light irradiation on the pitting corrosion performance of a Zr_(2)Ni metallic glass was examined using electrochemical methods and immersion test in 0.05 mol/L NaCl solution.From the results of potentiostatic polarization,the pitting potential of the ultraviolet light-irradiated sample shifted positively with a value of~300 mV,revealing the enhanced pitting corrosion resistance of the samples.The corrosion morphology after the immersion test also demonstrated lower degree of corrosion damage and improved pitting resistance of the sample with ultraviolet light irradiation.X-ray photoelectron spectroscopy analysis revealed more zirconium enrichment in the passive film and no chloride ions adsorption for the samples with ultraviolet irradiation,accounting for the suppression of the pit generation and growth.Our findings indicate that ultraviolet light irradiation improves the pitting corrosion resistance of the Zr-based metallic glasses,which are promising structural materials to be used in corrosion environments with high ultraviolet irradiation.

关键词： Metallic glass Pitting-Corrosion Ultraviolet light irradiation Passive film

Microstructure and mechanical properties of TiAl/TiAl joints brazed with a newly developed Ti–Ni–Nb–Zr quaternary filler alloy

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Progress in Natural Science:Materials International 2022年第6期32卷 758-768页

作者： H.S.Ren y.L.Shang X.y.Ren y.J.Jing H.P.Xiong y.y.Cheng Welding and Plastic Forming Division Beijing Institute of Aeronautical Materials

A novel Ti-Ni-Nb-Zr quaternary filler alloy with the composition of Ti-(19～25)Ni-(15～25)(Nb+Zr)(wt.%) was designed.The filler alloy was composed of(Ti,Nb)ss,(Ti,Zr,Nb)ss+(Ti,Zr)2Ni,α-Ti and Ti2Ni phases.It was fabricated into filler foil with a thickness of about 45 μm by a rapid solidification technique.The results indicate that the liquidus temperature of the Ti-Ni-Nb-Zr brazing alloy was about 978℃,and the brazing alloy presented excellent wettability on TiAl substrate.The TiAl joint mainly consisted of β/B2 phase,Ti2Al,Ti2AlNi and α2-Ti3Al phases.The diffusion of Al atom from base metal to brazed seam led to the formation of Ti2Al and Ti2AlNi.Considering that no previously references on XRD pattern of Ti2AlNi compound can be found,Ti2AlNi cast alloy specimen was specially prepared and XRD peaks were specially labeled.The micro-hardness and bending strength tests of the Ti2AlNi phase were carried out,and the results were 761 HV and 192 MPa,respectively.The brazing parameters of 1010 ℃/10 min offered the joint shear strength of 280 MPa at room temperature,and the joints exhibited tensile strength of 372 MPa at room temperature and 340 MPa at 750 ℃,indicating that the newly developed filler alloy could offer a stable high-temperature strength.

关键词： TiAl Brazing Filler alloy Microstructure Mechanical properties

Distinct Electrical and Mechanical Responses of a Cu-10Fe Composite Prepared by Hot-Pressed Sintering and Post Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 255-265页

作者： X.y.yue S.y.Peng X.Zhang C.N.He y.Z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution treated.The hot-pressed sintered and solution treated materials were rolled and aged.The precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron microscopy.In contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe composite.The Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACS and softening temperature of 838 K.Mechanisms for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were analyzed.These findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity

Frequency Veering of Rotating Metal Porous Twisted Plate with Cantilever Boundary Using Shell Theory

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Acta Mechanica Solida Sinica 2022年第2期35卷 282-302页

作者： y.y.Liu y.X.Hao W.Zhang L.T.Liu S.W.yang y.T.Cao College of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing 100192China College of Mechanical Engineering Beijing University of TechnologyBeijing 100124China

The frequency veering of a metal porous rotating cantilever twisted plate with twist angle and stagger angle is investigated.Metal porous materials may have the characteristics of gradient or uniform distribution along the thickness direction.Based on the classical shell theory,considering the influence of centrifugal force produced by high-speed rotation,the free vibration equations of a rotating cantilever twisted plate are derived.Through the polynomial function and Rayleigh-Ritz method,the natural frequencies and mode shapes of the metal porous cantilever twisted plate in both static and rotating states are derived.The accuracy of the present theory and calculation results is confirmed by a comparison between them and the results available from the literature and those obtained from Abaqus.The influences of the thickness ratio,porosity,twist angle,stagger angle and rotational velocity on the frequency veering and mode shape shift of the rotating cantilever twisted plate with porous material under three different distributions are analyzed.It should be mentioned that the frequency veering accompanied by mode shape shift occurs in both static and dynamic states.

关键词： Frequency veering Rotating twisted plate Cantilever boundary Metal porous

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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Journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.y.Huang Z.yang S.y.yang Z.H.Dai y.J.Liu J.H.Liao G.y.Zhong Z.J.Xie y.P.Fang S.S.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic reactions.Constructing photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor materials.Herein,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal method.The exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous catalyst.The unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the catalyst.Moreover,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of CdS.Under irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS catalyst.This study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocatalyst Hydrogen evolution