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P450cam突变体蛋白表达、纯化与结晶的改进及其四突变体(F87L/Y96F/L244A/v247A)晶体结构

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生物化学与生物物理进展 2004年第7期31卷 611-615页

作者：刘斌斌孙蕾徐峰娄智勇庞海 L.L.wong 刘一苇清华大学结构生物学实验室 Department of Chemistry Inorganic Chemistry Laboratory University of Oxford U.K.

在P4 5 0cam突变体蛋白纯化过程中使用 2 80nm/ 392nm双波长比值检测蛋白质纯度 ,采用 β 巯基乙醇对蛋白质进行还原性保护 ,有效地缩短了纯化进程 ,纯化效率相应提高 .以PEG 80 0 0为沉淀剂经悬滴汽相扩散法筛选得到适合衍射的P4 5 0ca... 详细信息

在P4 5 0cam突变体蛋白纯化过程中使用 2 80nm/ 392nm双波长比值检测蛋白质纯度 ,采用 β 巯基乙醇对蛋白质进行还原性保护 ,有效地缩短了纯化进程 ,纯化效率相应提高 .以PEG 80 0 0为沉淀剂经悬滴汽相扩散法筛选得到适合衍射的P4 5 0cam四突变体 (F87L/Y96F/L2 4 4A/v2 4 7A)晶体 ,在Mar Research面探测器系统上收集了0 2 2nm分辨率的X射线衍射数据 .采用同晶差值傅立叶法解析结构 ,最后的晶体学R因子和Rfree分别为 0 197和 0 2 4 7,键长偏差为 0 0 0 177nm ,键角偏差为 1 96°.结构测定显示P4 5 0cam四突变体 (F87L/Y96F/L2 4 4A/v2 4 7A)和P4 5 0cam野生型的整体构象无重大变化 ,突变后活性口袋变大而疏水性增加 ,这与突变设计预期目标一致 .

关键词： P450cam 四突变体纯化双波长检测晶体结构

Ultralow switching voltage and power consumption of GeS_(2)thin film resistive switching memory

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Journal of Advanced Dielectrics 2021年第1期11卷 22-29页

作者： N.Lyapunov C.H.Suen C.M.wong Xiaodan Tang Z.L.Ho K.Zhou X.X.Chen H.M.Liu Xiaoyuan Zhou J.Y.Dai Department of Applied Physics The Hong Kong Polytechnic UniversityHong KongP.R.China College of Physics Chongqing UniversityChongqing 401331P.R.China

The coming Big Data Era requires progress in storage and computing *** an emerging memory technology,Resistive RAM(RRAM)has shown its potential in the next generation high-density storage and neuromorphic computing applications,which extremely demand low switching voltage and power *** this work,a 10 nm-thick amorphous GeS_(2)thin film was utilized as the functional layer of RRAM in a combination with Ag and Pt *** structure and memory performance of the GeS_(2)-based RRAM device was characterized-it presents high on/off ratio,fast switching time,ultralow switching voltage(0.15 v)and power consumption(1.0 pJ and 0.56 pJ for PROGRAM and ERASE operations,respectively).we attribute these competitive memory characteristics to Ag doping phenomena and subsequent formation of Ag nano-islands in the functional layer that occurs due to diffusion of Ag from electrode into the GeS_(2)thin *** properties enable applications of GeS_(2)for low energy RRAM device.

关键词： GeS_(2) conductive bridge memory thin film resistive switching memory

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二茂钌共轭大环氮杂冠醚的合成及结构

高等学校化学学报 1999年第12期20卷 1838-1841页

作者：尹业高易长海张恭启黄永德荆州师范学院化学系荆州434100 香港大学化学系

合成并表征了质子化的 N - (二茂钌基甲基 ) - 1,4 ,7-三氮杂 - 9-冠 - 3(1)和 N ,N′,N″-三 - (二茂钌基甲基 ) - 1,4 ,7-三氮杂 - 9-冠 - 3(2 ) .用 X射线衍射法测定了化合物 2的结构 .化合物 2的晶体属 P2 1/ a空间群 .晶胞参数 a=1... 详细信息

合成并表征了质子化的 N - (二茂钌基甲基 ) - 1,4 ,7-三氮杂 - 9-冠 - 3(1)和 N ,N′,N″-三 - (二茂钌基甲基 ) - 1,4 ,7-三氮杂 - 9-冠 - 3(2 ) .用 X射线衍射法测定了化合物 2的结构 .化合物 2的晶体属 P2 1/ a空间群 .晶胞参数 a=1.4 2 85(3) nm,b=1.9888(3) nm,c=1.9133(3) nm;β=10 9.12 (2 )°;v=5.1358(1.0 ) nm3 ;Z=4 .Dc=1.6 6 5g/ cm3 . 1和 2的核磁共振谱表明 ,化合物中取代 Cp环上质子的共振吸收较二茂钌 Cp环上质子的吸收向低场移动 .这表明质子化的 1,4 ,7-三氮杂 - 9冠 - 3对 Cp环上质子具有去屏蔽作用 .化合物 2的电位扫描曲线在 0 .84

关键词：二茂钌核磁共振氮杂冠醚钌金属中心配合物

经颅多普勒超声（TCD）的实践标准——第2部分：临床适应证和预期结果

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国际脑血管病杂志 2012年第1期20卷 1-11页

作者： Andrei v. Alexandrov Michael A. Sloan Charles H. Tegeler David N. Newell Alan Lumsden Zsolt Garami Christopher R. Levy Lawrence K.S. wong Colleen Douville Manfred Kaps 李海峰（译）李宏（译）李展秀（译） From the Comprehensive Stroke Center University of Alabama at Birmingham Birmingham AL 青岛大学医学院附属医院神经内科

引言：经颅多普勒（transcranial Doppler，TCD）已被证实为一种安全有效的生理学超声检查技术。尽管成像设备可以在结构影像的基础上显示颅内血流，但成像性双功能超声或非成像性TCD检查提供的最终结果是通过频谱波形来评价生理学血流... 详细信息

引言：经颅多普勒（transcranial Doppler，TCD）已被证实为一种安全有效的生理学超声检查技术。尽管成像设备可以在结构影像的基础上显示颅内血流，但成像性双功能超声或非成像性TCD检查提供的最终结果是通过频谱波形来评价生理学血流参数。总结概要：多学科专家小组确定的TCD临床适应证包括：镰状细胞病、恼缺血、右向左分流（right—to—left shunt，RLS）、蛛网膜下腔出血、脑死亡以及围手术期或术中监测。TCD检查可常规应用于住院或门诊患者的一些临床实践活动：通过完整或部分TCD检查以检测正常、狭窄或闭塞的颅内血管和侧支循环来判断动脉闭塞位置，并进一步完善颈动脉超声或无创性血管造影结果；通过血管运动反应性检查来识别首发或复发性卒中的高危患者；通过栓子监测对脑栓塞进行实时检查、定位和量化；在怀疑反常性栓塞或考虑分流封堵术治疗的患者中进行RLS检测；对溶栓治疗进行监测以促进血管再通和检测再闭塞；在血管内支架置入术、颈动脉内膜切除术和心脏外科手术中进行监测以发现围手术期栓塞、血栓形成、低灌注或高灌注。结论：通过界定实践范围，这些标准将在TCD检查的申请、检查和评价过程中给开申请单的医生、发报告的医生以及第三方提供帮助。

关键词： TCD 适应证应用结果

在^(68)Ga EDTA 动态 PET分析中用正常区域取样和参数成像实现大脑肿瘤的统计分割研究(英文)

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中国医学物理学杂志 2002年第4期19卷 209-215页

作者：周云黄嵩正包尚联 D.F.wong 约翰霍普金斯大学放射系加州大学洛杉矶分校分子和医药系北京大学物理学院肿瘤物理诊疗技术研究中心重离子物理研究所和北京市重点实验室:医学物理和工程北京100871

为了研究和评价用68GaEDTA动态PET研究和评价脑肿瘤定量分析的可靠性和灵敏度,我们在本文中提出了估计容积分布(distributionvolume:Dv)和血脑屏障渗透率(k1)分布的线性参数成像模型。我们还用F统计学方法实现了把肿瘤从正常组织中分割... 详细信息

为了研究和评价用68GaEDTA动态PET研究和评价脑肿瘤定量分析的可靠性和灵敏度,我们在本文中提出了估计容积分布(distributionvolume:Dv)和血脑屏障渗透率(k1)分布的线性参数成像模型。我们还用F统计学方法实现了把肿瘤从正常组织中分割出来的方法。用一个三参数双腔室模型描述用PET测量的数据。用于估计Dv(=K1/k2)和K1的主要计算公式为:Cpet=(K1+k2vp)t0∫Cpds-k2t0∫Cpetds+vpCp和t0∫Cpetds=(Dv+vp)t0∫Cpds-(1/k2)Cpet+(vp/k2)Cp,这里的k2是脑内通过血脑屏障到脑外的渗透率。在参数成像中我们采用了一个可靠和如棒的基于像素的局域线性回归算法用于产生Dv和K1图像。同样基于像素自由度为2和k-2的F统计学方法采用的计算公式为:F=(((k-2)k/(2(k2-1)))D2,这里的D2=(x-μ)'S-1(x-μ),而μ和S分别表示脑肿瘤对侧正常区域内采集的样品的平均值和协方差,这些样品是按照二维空间狖(K1,Dv)狚采集的,而常数k是取样的总数。在不同水平上阈值α,就可以得到不同置信度下的F统计图像。用这个方法对11个肿瘤病人进行了68GaEDTA动态PET研究。研究结果表明:所有的Dv,K1和F图像的质量都很好。而且用于产生Dv,K1和不同置信度下的F图像的算法效率很高,容易实现。本研究方法中研究和发展的方法提供了一个有效的集成多维生?

关键词：大脑肿瘤统计分割 ^68GaEDTA动态PET成像线性参数成像算法双腔室三参数模型

Simulation of Preform Strain State in Different Processes of Spinning

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Simulation of Preform Strain State in Different Processes of...

Development of Jacket Platform Tsunami Risk Rating System in waters Offshore North Borneo

The Fourth International Conference on Physical and Numerical Simulation of Materials (ICPNS’2004)

作者： v.I.Korolkov Th voronezh state technical university Russia 394026. Voronezh Moscow avenue 14 faculty of aircraft construction

＜正＞The model of process of a rotation extract of thin-wall shell details without deliberate thining, taking into account the sizes of the center of plastic deformation, treatment schedules, friction, rejected tags, pathways of motion and sizes of the distorting tool is esteemed. The problem of defining of the deformed condition is decided by minimization of plastic work of *** formmaking of shells by methods of a rotation extract is an effective process of manufacturing of thin-wall details. This process is distinguished by the low cost of a technological equipment, reduction of quantity of technological transitions and concentration of several operations on one equipment at enough split-hair accuracy both surface figure of details and capability of manufacturing details of the considerable sizes. Allowing rather low energy output of process, it is possible to consider it as perspective for modern floppy production. The bottleneck of applying know-hows of a rotation extract is designing of a master schedule and pathways of movement of the distorting tool in process of formmaking. During a rotation extract there is a local cyclical appendix of a distorting effort to rotated bar, that causes complexities at calculation deformed and stressed state of a moulded shell at present instants of ***-term theoretical and the experimental researches of process have allowed to create rather prime model of the deformed condition of bar. The given model bases on the justified and tested hypothesis about z-axes symmetry of the deformed condition of a shell after a complete cycle of movement of the center of plastic deformation in a circumferential direction. This hypothesis allows at calculation to eliminate from consideration the movement of the center in a circumferential direction and to esteem movement of the center of plastic deformation only in a meridional direction in all processes of a rotation extract: without deliberate thining and with the thining at m

关键词： Spinning Thin-wall Shell Simulation

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Journal of Marine Science and Application 2016年第3期15卷 307-320页

作者： H.E. Lee M.S. Liew N.H. Mardi K.L. Na Iraj Toloue S.K wong Offshore Engineering Centre Universiti Teknologi PETRONA& 32610 Perak Malaysia Faculty of Geoscience and Petroleum Engineering Universiti Teknologi PETRONAS 32610 Perak Malaysia Department of Civil Engineering Univerisiti Tenaga Nasional Selangor 43650 Malaysia Department of Civil & Environmental Engineering Universiti Teknologi PETRONAS 32610 Perak Malaysia

This work details the simulation of tsunami waves generated by seaquakes in the Manila Trench and their effect on fixed oil and gas jacket platforms in waters offshore North Borneo. For this study, a four-leg living quarter jacket platform located in a water depth of 63 m is modelled in SACS v5.3. Malaysia has traditionally been perceived to be safe from the hazards of earthquakes and tsunamis. Local design practices tend to neglect tsunami waves and include no such provisions. In 2004, a 9.3Mw seaquake occurred off the northwest coast of Aceh, which generated tsunami waves that caused destruction in Malaysia totalling US$ 25 million and 68 deaths. This event prompted an awareness of the need to study the reliability of fixed offshore platforms scattered throughout Malaysian waters. In this paper, we present a review of research on the seismicity of the Manila Trench, which is perceived to be high risk for Southeast Asia. From the tsunami numerical model TUNA-M2, we extract computer-simulated tsunami waves at prescribed grid points in the vicinity of the platforms in the region. Using wave heights as input, we simulate the tsunami using SACS v5.3 structural analysis software of offshore platforms, which is widely accepted by the industry. we employ the nonlinear solitary wave theory in our tsunami loading calculations for the platforms, and formulate a platform-specific risk quantification system. we then perform an intensive structural sensitivity analysis and derive a corresponding platform-specific risk rating model.

关键词： finite element analysis North Borneo jacket platforms Manila Trench seaquake SACS TUNA-M2 tsunami simulation risk rating system risk rating model

CRYSTAL STRUCTURES OF 1,2-BENZO[2.2]PARACYCLOPHANE AND 1,2-BENZO[2.2]PARACYCLOPHANE-1,7-DIENE

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结构化学 1985年第3期 214-217页

作者：黄乃正陈展榮麥松威 Department of Chemistry The Chinese University of Hong Kong Shatin New Territories Hong Kong

C20H16 (1) Mr = 256.34 and C20H14 (2), Mr = 254.32 are isomorphous, orthorhombic, P212121, Z = 4. For (?), ?a= 7.116(1), b =7.874(2), c = 24.564(4) A, v = 1376.4(3) A3, Dx = 1.237 g cm-3, μ(Mo-K α) =0.65 cm-1 , final R = 0.047 for 1152 observed reflections; for 2, a=6.963(2), b = 7.985(4), c = 24.315(8) A, v = 1351.9(8) A3, Dx = 1.250 g cm-3,μ(Mo-Kα) = 0.66 cm-1 , final R = 0.076 for 886 observed data. Structuralfeatures are similar to those of the parent [2.2]paracyclophane and related derivatives.

关键词： parent orthorhombic fused substitution benzene morethan bonds diene adequately allowed

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有限图的字典积的自同构群

数学进展 2022年第6期51卷 996-1004页

作者：王志俊王登银中国矿业大学数学学院徐州江苏221116

两个简单无向图G和H的字典积G∘H是一个以v(G)×v(H)为顶点集的图,两个顶点(i,h)和(j,k)在G∘H中邻接当且仅当i和j在G中邻接,或者i=j且h和k在H中邻接.图G∘H的自同构群Aut(G∘H)包含图G和图H的自同构群的圈积Aut(H)≀Aut(G)作为子群.Sabi... 详细信息

两个简单无向图G和H的字典积G∘H是一个以v(G)×v(H)为顶点集的图,两个顶点(i,h)和(j,k)在G∘H中邻接当且仅当i和j在G中邻接,或者i=j且h和k在H中邻接.图G∘H的自同构群Aut(G∘H)包含图G和图H的自同构群的圈积Aut(H)≀Aut(G)作为子群.Sabidussi给出了一个Aut(G∘H)=Aut(H)≀Aut(G)的充分必要条件.在此基础上,本文确定了任意两个有限图字典积的自同构群.

关键词：字典积图图的自同构半直积圈积