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Acta mechanica Sinica 1995年第1期11卷 34-43页

作者： G.j.molina y.m.Haddad Dept.of mechanical Engineering University of OttawaOttawaCanada K1N 6N5

This paper deals with the application of Acousto-ultrasonics,in con- junction with Pattern Recognition and Classification techniques,to the identification of residual impact properties of a class of polymeric material,namely,Polyvinylchlo- ride(PVC).PVC specimens of different low-energy repeated impact damage states are processed by Acousto-ultrasonics(AU)to retrieve AU signals in the form of dig- italized *** AU signals are grouped as distinct classes,each pertaining to a known level of repeated impact *** features of these AU signals are used to build Pattern Recognition(PR)*** classifiers are used to identify unknown damage states in other PVC specimens by classifying the re- trieved AU signals as belonging to one of the *** obtained results indicate that Acousto-ultrasonics in combination with Pattern Recognition and Classification techniques can be used for the quantitative non-destructive identification of damage states in PVC specimens of unknown low-energy repeated impact conditions.

关键词： pattern recognition acousto-ultrasonics impact damage quantitative non-destructive examination

全球变暖背景下青藏高原北缘气候干湿变化模式的转型与机制——古气候视角

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中国科学：地球科学 2024年第6期54卷 1960-1979页

作者：李育张占森周雪如高铭君段俊杰薛雅欣尚好刘世瑜兰州大学西部环境教育部重点实验室兰州大学资源环境学院兰州730000

青藏高原北缘是季风西风协同影响的敏感区.夏季,水汽输送可以到达青海湖和祁连山东段;冬季,气候主要受控于西风.本文从古气候视角,对比了该区域中全新世暖期、中世纪暖期、现代暖期和未来百年暖期的干湿变化,发现中全新世暖期主要受轨... 详细信息

青藏高原北缘是季风西风协同影响的敏感区.夏季,水汽输送可以到达青海湖和祁连山东段;冬季,气候主要受控于西风.本文从古气候视角,对比了该区域中全新世暖期、中世纪暖期、现代暖期和未来百年暖期的干湿变化,发现中全新世暖期主要受轨道控制的东亚夏季风影响,区域整体表现出温暖湿润的气候特征;中世纪暖期主要受控于太阳辐射,存在暖干的现象;现代暖期和未来百年暖期主要由温室气体增加导致的温度升高控制,气候干旱化趋势显著.青藏高原北缘现代暖期和未来百年暖期的干湿格局与中世纪暖期类似,而持续升温会导致西风带扩张,气候逐渐湿润,未来干湿变化将与中全新世暖期更加相似.

关键词：青藏高原北缘干湿变化暖期相似驱动机制未来评估

共享社会经济路径(SSP1~5)中国及分省经济预估数据集_v2

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气候变化研究进展 2024年第4期20卷 498-503页

作者：杨聿铭翟建青苏布达景丞姜彤郭欢欢南京信息工程大学地理科学学院/灾害风险管理研究院南京210044 南京信息工程大学气候与环境治理研究院南京210044 中国气象局国家气候中心北京100081 中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室乌鲁木齐830011 江苏第二师范学院地理科学学院南京210013

随着全球经济快速增长,特别是基于传统工业化模式的增长,增加了化石燃料的使用,造成气候变暖和极端天气事件增加[1]。在追求短期经济利益的压力下,一些政府可能忽视或延迟实施必要的环境保护和气候治理措施。加之快速城市化和工业化导... 详细信息

随着全球经济快速增长,特别是基于传统工业化模式的增长,增加了化石燃料的使用,造成气候变暖和极端天气事件增加[1]。在追求短期经济利益的压力下,一些政府可能忽视或延迟实施必要的环境保护和气候治理措施。加之快速城市化和工业化导致对煤炭、石油等化石能源的需求激增,温室气体大量排放,气候进一步恶化,气候治理的难度加大。快速经济增长常常伴随着对自然资源的消耗,包括水资源、森林、矿产等,这不仅直接破坏了自然环境,还会降低这些生态系统对气候变化的适应能力和减缓作用。气候风险研究在应对气候变化方面发挥着关键作用,它包括对未来气候条件的预估,评估气候变化对环境、经济和社会的潜在影响,以及制定适应和减缓气候变化的策略。

关键词：工业化模式未来气候极端天气事件气候变化化石燃料气候治理环境保护快速城市化

应用剪切波离散成像斜率值预测移植肾急性排异反应

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国际医学放射学杂志 2024年第5期 620-621页

作者： T.m.Kim H.Ahn j.y.Cho A.Han S.I .min j.Ha 郑永利

目的评价剪切波离散成像斜率值预测移植肾功能不全的价值。方法回顾性分析2022年11月—2023年2月期间行肾移植的128例受试者资料[中位年龄，55(43～62)

关键词：

接受抗高血压药治疗的高血压患者夜间高血压的影响因素

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中华高血压杂志(中英文) 2024年第3期32卷 300-300页

作者： maruhashi T Kinoshita y Ozono R Nakamaru m Ninomiya m Oiwa j Kawagoe T yoshida O matsumoto T Fukunaga y Sumii K Ueda H Shiode N Takahari K Hayashi y Ono y Nakano y Takahashi m Kihara y Higashi y 刘青练桂丽

背景：通过家庭血压监测（home blood pressure monitoring,HBPm）设备评估的夜间高血压与心血管事件风险增加相关。然而，经常评估夜间血压仍然很困难。该项横断面研究的目的是确定设备对接受抗高血压药治疗的高血压患者采用HBPm设备...

背景：通过家庭血压监测（home blood pressure monitoring,HBPm）设备评估的夜间高血压与心血管事件风险增加相关。然而，经常评估夜间血压仍然很困难。该项横断面研究的目的是确定设备对接受抗高血压药治疗的高血压患者采用HBPm设备评估的夜间高血压的影响因素。方法：研究者使用HBPm设备连续7d测量365例接受药物治疗的高血压患者的夜间血压、早晨血压、晚上血压和睡前血压。

关键词：

青藏高原及其周边第四纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 1379-1410页

作者：王永郑绵平凌媛向树元邵兆刚张克信柯学林晓韩芳韩建恩中国地质科学院地质研究所北京100037 中国地质科学院矿产资源研究所北京100037 中国地质大学(武汉)地球科学学院武汉430074 中国地质科学院北京100037 中国地质大学(武汉)地质调查研究院武汉430074 东华理工大学地球科学学院南昌330013 中国地质科学院地质力学研究所北京100081

青藏高原第四纪地层蕴含丰富的古气候与环境演变信息,记录了高原第四纪区域构造、古地理和地貌演化过程,是研究第四纪地质事件和区域环境演变极其重要的地区.根据区域地层资料的综合分析和生物群等的发育演化特征,基于岩石地层单元、沉... 详细信息

青藏高原第四纪地层蕴含丰富的古气候与环境演变信息,记录了高原第四纪区域构造、古地理和地貌演化过程,是研究第四纪地质事件和区域环境演变极其重要的地区.根据区域地层资料的综合分析和生物群等的发育演化特征,基于岩石地层单元、沉积特征及地貌、流域水系的差异,将青藏高原及其周边第四纪地层划分为5个地层区:塔里木区、黄土高原区、青藏高原区、云贵高原区及印度-恒河区.并将青藏高原地层区划分为西昆仑-喀喇昆仑分区、阿尔金-祁连山分区、柴达木-河湟分区、东昆仑-巴颜喀拉分区、羌塘分区、藏东-滇西-川西分区及冈底斯-喜马拉雅分区等7个地层分区.简要描述了青藏高原7个地层分区的岩石地层单元,根据各个地层分区的岩石地层序列及其沉积特征、地层接触关系、形成时代与生物群演化,将青藏高原第四纪的构造古地理演化划分为4个阶段:(1) 2.6~1.8/1.5ma,上新世以来继承性差异隆升阶段,区域沉积差异显著,地层分布较局限,沿山前地带普遍发育冲洪积砂砾岩,山间低洼地河湖相沉积发育;(2) 1.8/1.5~1.2/0.8ma,高原整体夷平阶段,高原及周边不整合面广泛分布,大型河流形成,山间盆地及高原腹地发育湖泊沉积物;(3) 1.2/0.8~0.128ma,高原大范围持续隆升,地形差异显著,山体切割加剧,约0.8ma高原进入冰冻圈,山地冰川发育,高寒干旱环境逐步形成;(4)0.128ma~,山体上升与侵蚀切割加剧,山间盆地湖泊广泛分布,区域沉积特征差异较大,沉积类型向多样化发展,现代高原地貌格局基本形成.

关键词：青藏高原第四纪地层对比生物群古地理

Coupled pile soil interaction analysis in undrained condition

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journal of Central South University 2013年第5期20卷 1376-1383页

作者： m.y.Fattah F.A.Salman y.j.Al-Shakarchi A.m.Raheem Building and Construction Engineering Department University of Technology Department of Civil Engineering Faculty of EngineeringUniversity of Malaya Department of Civil Engineering College of EngineeringUniversity of Baghdad Department of Civil Engineering College of EngineeringUniversity of Kirkuk

The effective stress method is developed to predict the axial capacity of piles in clay. The effective stress state changes due to the resulting pore pressure change and therefore, the strength and stiffness of the soil will change. In this work, the finite element method is utilized as a tool for the analysis of pile-soil systems in undrained condition. The computer program CRISP was developed to suit the problem requirements. CRISP uses the finite element technique and allows predictions to be made of ground deformation using critical state theories. Eight-node isoparametric element was added to the program in addition to the slip element. A pile loading problem was solved in which the pile-soil system is analyzed in undrained condition. The pile is modelled as elastic-plastic material, while the soil is assumed to follow the modified Cam clay model. During undrained loading condition, the settlement values increase by 22% when slip elements are used. The surface settlement increases by about three times when the load is doubled and the surface settlement at all points increases when using slip elements due to the mode of motion which allows smooth movement of the adjacent soil with respect to the pile. The vertical displacement increases as the distance decreases from the pile and negligible values are obtained beyond 10D (where D is the pile diameter) from the center of the pile and these values are slightly increased when slip elements are used. The vertical effective stress along a section at a distance D from the pile center is approximately the same for all load increments and lower values of effective vertical stress can be obtained when slip elements are used.

关键词： pile finite element coupled analysis undrained condition

Ibuprofen-Induced Toxic Epidermal Necrolysis:A Case Report

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International journal of Dermatology and Venereology 2024年第2期7卷 108-110页

作者： Nevin Kannappilly mohamed Z.Peediyakkal mohamad y.Khatib Dore C.Ananthegowda moustafa S.Elshafei Hani El Zeer Karimulla S.Shaik moayad m.AlFayoumi Dyaneshwar P.mutkule Ahmed A.Soliman Abdulqadir j.Nashwan Critical Care Department Hamad Medical Corporation(HMC)Doha 3050Qatar

Introduction:Toxic epidermal necrolysis(TEN)is a medical emergency that most commonly occurs as an adverse effect of certain ***,we describe a case of a 41-year-old man with no comorbid illness who developed *** presentation:The patient had been prescribed ibuprofen for myalgia and developed skin lesions after the single *** lesions were erythematous papules and macules distributed all over the body after ibuprofen *** was diagnosed based on the patient’s clinical presentation and laboratory *** was treated with intravenous dexamethasone,intravenous immunoglobulin,and *** dressing changes and skin care was done with saline,chlorhexidine,and liquid *** patient was intubated and tracheostomized,and he gradually improved and ***,he developed septicemia in the intensive care unit and was treated ***:The management of TEN includes cessation of the causative cause,multidisciplinary intensive care unit(ICU)care,prevention and early detection of sepsis,fluid and electrolyte balance,adequate analgesia and temperature control,proper organ support,aggressive nutritional management,and good psychological *** pharmacological therapy for TEN includes corticosteroids,intravenous immunoglobulin,and *** key elements of management are aseptic care and proper dressing of the ***:TEN is associated with high mortality if not managed in a systemic and protocolized way.

关键词： ibuprofen toxic epidermal necrolysis erythema drug-induced erythema

Spectroscopic investigations on yb^3+ doped and Pr^3+/yb^3+ codoped tellurite glasses for photonic applications

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journal of Rare Earths 2021年第1期39卷 33-42,I0002页

作者： m.Seshadri m.j.V.Bell V.Anjos y.messaddeq Grupo de Engenharia e Espectroscopia de materiais Departamento de Fisica-ICEUniversidade Federal de Juiz de ForaJuiz de ForaMG36036-900Brazil Centre d'Optique Photonique et Laser2375 Rue de la TerrasseUniversite LavalQuebecQCG1V 0A6Canada

In this work we repo rt on structural and spect roscopic properties of yb^3+doped and Pr^3+/yb^3+co-doped TeO2-Bi2 O3-ZnO-Li2 O-Nb2 O5(TBZLN)tellurite *** and stretching modes of TeO2 and Te-OH bond(strong and weak)were analysed from the deconvolution of observed Raman and FT-IR *** on the absorption measurements,the energy bands of yb^3+and Pr^3+ions are *** spectroscopic properties for the radiative transitions of yb^3+and Pr^3+ions were reported using mcCumber and judd-Ofelt *** emission bands originating from 3 P1 and 3 P0 to lower lying levels of Pr^3+were registered under 447 nm *** emission band around 1334 nm assigned to the Pr3:1 G4→3 H5 was observed when excited at 980 *** stimulated emission cross-section(σemi(λ))and effective linewidth(Δλeff)for the 3 P1→3 H6,3 P1→3 H5,3 P0→3 H6,3 P0→3 F2,3 P1→3 F3,3 P1→3 F4,3 P0→3 F4 and 1 G4→3 H5 transitions of Pr^3+are *** luminescence in Pr^3+/yb^3+codoped glass upon 980 nm excitation was *** resonant transfer processes between yb^3+and Pr^3+ions are presented and *** chromaticity co-ordinates were also evaluated from the visible emission spectra showing that Pr^3+/yb^3+co-doped glass may be suitable for the development of yellow-orange(λexc=447 nm)and near white light(λexc=980 nm)emitting devices in photonics.

关键词： Rare earth ions Tellurite glass Spectroscopic properties Upconversion luminescence

Purification of L-asparaginase II by crystallization

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Frontiers of Chemical Science and Engineering 2013年第1期7卷 37-42页

作者： y. LIU m. PIETZSCH j. ULRICH Thermal Process Engineering Center for Engineering Science Martin Luther University Halle-Wittenberg D-06099 Halle (Saale) Germany Department of Downstream Processing Institute of Pharmacy Faculty of Natural Sciences I Martin Luther University Halle-Wittenberg D-06099 Halle (Saale) Germany

Here a case study ofL-asparaginase II out of a recombinant Escherichia coli is presented. The target protein was obtained by simple cell disintegration and acetone precipitation. The L-asparaginase II has been crystallized in three different forms in the following microbatch crystallization. The rod-shaped crystals （-400 μm edge length） were obtained at either 8℃ or 22℃ after 17h by addition of PEG6ooo. The rectangular-shaped crystals were obtained after further recrystallization of the rod-shaped crystals. The rhombic-shaped crystals formed at 8℃ after 12 days when cold ethanol was used instead of PEG6000. All crystallizations were performed in tris-acetate buffer （50mmol-L-1, pH 5.1）. By crystallization, the specific activity of L-asparaginase II has increased 5-fold. The protein content and the purity of the crystals were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis （SDS-PAGE）. The more concentrated L- asparaginase II out of an extract mixture and the presence of only less minor proteins after crystallization demonstrates that crystallization is an effective and mild method to purify the target protein. The single crystal X-ray diffraction pattern reveals that the crystals are proteins and the X-ray powder diffraction （XRPD） pattern shows clearly that the crystals forming in PEG600o and ethanol have different crystal structures.

关键词： protein crystallization L-asparaginase II purification