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基于SHPB试验的钢纤维混凝土动态性能研究

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水电能源科学 2010年第2期28卷 103-105页

作者：蒋国平焦楚杰任达广州大学工程抗震研究中心广东广州510405 广州大学土木工程学院广东广州510006

采用分形理论研究了钢纤维混凝土和素混凝土在SHPB(分离式Hopkinson压杆)试验中的裂纹特性,分析了断裂表面的分形性质与材料属性及冲击压力的关系,给出了混凝土断裂表面分形的特点,采用计盒方法(FIPS程序)计算了混凝土分形维数,建立了... 详细信息

采用分形理论研究了钢纤维混凝土和素混凝土在SHPB(分离式Hopkinson压杆)试验中的裂纹特性,分析了断裂表面的分形性质与材料属性及冲击压力的关系,给出了混凝土断裂表面分形的特点,采用计盒方法(FIPS程序)计算了混凝土分形维数,建立了损伤因子与分形维数的函数关系。结果表明,该方法为探索混凝土表面裂纹图形的分形特征与其承受的动荷载之间的内在规律、建立适合描述混凝土分形结构和分形行为的数学力学方法及基本理论寻求了新途径。

关键词：分离式Hopkinson压杆混凝土动态本构关系冲击分形

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某全钢结构地震模拟振动台试验和理论研究

世界地震工程 2003年第3期19卷 97-103页

作者：杨巧荣陈建秋刘文光魏陆顺广州大学土木工程学院广东广州510405 广州大学工程抗震研究中心广东广州510405

对体型不规则的全钢结构建筑进行了地震模拟振动台试验研究和理论分析,这种结构体系是由内椭球塔与外框筒连接而成的特殊结构体系。地震模拟试验结果表明这种结构体系仍然以主振型为主,内椭球塔与外框筒连接方式能够满足设计要求。文末... 详细信息

对体型不规则的全钢结构建筑进行了地震模拟振动台试验研究和理论分析,这种结构体系是由内椭球塔与外框筒连接而成的特殊结构体系。地震模拟试验结果表明这种结构体系仍然以主振型为主,内椭球塔与外框筒连接方式能够满足设计要求。文末采用SAP2000程序对结构模型进行三维受力分析,沿最不利加振方向的理论分析结果与振动台试验结果显示该结构在设计地震作用下,具有足够的安全性。

关键词：钢结构地震反应振动台试验理论研究

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建筑用铅芯橡胶隔震支座温度性能研究

世界地震工程 2003年第2期19卷 39-44页

作者：刘文光杨巧荣周福霖北京工业大学建筑工程学院北京100022 广州大学地震工程研究与试验中心广东广州510405

详细研究了建筑隔震结构中铅芯橡胶隔震支座的温度特性。内容包括三个方面:首先是一定温度条件下进行的温度相关性试验,温度范围由-20℃至40℃;其次进行了高温燃烧并经冷却后的基本性能及界限性能试验;最后研究完成了恒温100℃状态下老... 详细信息

详细研究了建筑隔震结构中铅芯橡胶隔震支座的温度特性。内容包括三个方面:首先是一定温度条件下进行的温度相关性试验,温度范围由-20℃至40℃;其次进行了高温燃烧并经冷却后的基本性能及界限性能试验;最后研究完成了恒温100℃状态下老化185小时和240小时的长期性能试验。在试验结果的基础上,提出了支座屈服后刚度及屈服荷载的温度修正方程。

关键词：建筑隔震结构铅芯橡胶隔震支座温度老化耐火性能火灾

Loss of energetic particles due to feedback control of resistive wall mode in HL-3

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Plasma Science and Technology 2024年第10期26卷 17-28页

作者： Yifei ZHAO Yueqiang LIU guangzhou HAO Zhengxiong WANG Guanqi DONG Shuo WANG Chunyu LI Guanming YANG Yutian MIAO Yongqin WANG Dalian university of Technology Dalian 116024People’s Republic of China General Atomics San Diego CA 92186-5608United States of America Southwestern Institute of Physics Chengdu 610041People’s Republic of China

Effects of three-dimensional(3D)magnetic field perturbations due to feedback control of an unstable n=1(n is toroidal mode number)resistive wall mode(RWM)on the energetic particle(EP)losses are systematically investigated for the HL-3 *** MARS-F(Liu et al 2000 *** 73681)code,facilitated by the test particle guiding center tracing module REORBIT,is utilized for the *** RWM is found to generally produce no EP loss for cocurrent particles in *** the same perturbation level at the sensor location for the close-loop system,feedback produces nearly the same loss of counter-current EPs compared to the open-loop *** however that the sensor signal is ten times smaller in the close-loop system than the open-loop counter part(reflecting the fact that the RWM is more stable with feedback),the counter-current EP loss is found significantly reduced in the *** of EP losses occur only for particles launched close to the plasma edge,while particles launched further away from the plasma boundary experience much less *** strike points of lost EPs on the HL-3 limiting surface become more scattered for particles launched closer to the plasma *** into account the full gyro-orbit of particles while approaching the limiting surface,REORBIT finds slightly enhanced loss fraction.

关键词： energetic particles resistive wall mode HL-3

Efficient transformation and expression of gfp gene in the edible mushroom Pleurotus nebrodensis

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Progress in Natural Science:Materials International 2008年第7期18卷 819-824页

作者： Junfang Lin a,b, Mingyao Zheng a, Jie Wang a,b, Wei Shu c, Liqiong Guo a,b,* a Department of Biotechnology, College of Food Sciences, South china Agricultural university, guangzhou 510640, china b Institute of Biomass research, South china Agricultural university, guangzhou 510640, china c test and Experimental center, South china Agricultural university, guangzhou 510640, china Department of Biotechnology College of Food Sciences South China Agricultural University Guangzhou 510640 China Institute of Biomass research South China Agricultural University Guangzhou 510640 China test and Experimental center South China Agricultural University Guangzhou 510640 China

An efficient transformation method mediated by PEG-protoplasts was developed for the newly commercial edible mushroom Pleu- rotus nebrodensis. Two plasmids were used to co-transform protoplasts of P. nebrodensis. One plasmid is pAN7-1 containing a positive selectable marker gene hph conferring hygromycin B resistance. Another plasmid is pBlue-GFP containing a reporter gene gfp conferring green fluorescent protein. PCR and Southern blot analysis showed that hph gene or/and gfp gene were integrated into the genome of P. nebrodensis transformants. The transformation efficiency of the positive selectable marker gene hph was 3 transformants per microgram of plasmid pAN7-1 DNA, which was about 30 times higher than that previously reported in thoroughly studied Pleurotus species such as Pleurotus ostreatus. The transformation efficiency of the reporter gene gfp was 9 transformants per microgram of plasmid pBlu-GFP DNA. The co-transformation efficiency was 23.68%. This is the first report that a "reporter" gene, green fluorescent protein gene can be successfully stably expressed in this Pleurotus species.

关键词： Pleurotus nebrodensis Protoplast-mediated transformation Green fluorescent protein GFP expression

Microstructure and formation mechanism of twins of laths of austenite with high nitrogen

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Science china(Technological Sciences) 2007年第6期50卷 755-764页

作者： WU CuiLan1,2 & LUO ChengPing2 1 center for High Resolution Electron Microscopy, College of Materials Science and engineering, Hunan university, Changsha 410082, china 2 College of Mechanical engineering, South china university of Technology, guangzhou 510641, china center for High Resolution Electron Microscopy College of Materials Science and Engineering Hunan University Changsha China College of Mechanical engineering South China University of Technology Guangzhou China

The microstructure of composite diffusion layer of the nitrided and chromized 0.2% carbon steel is investigated using TEM and EDS. It is found that laths of austenite with high nitrogen (γ N) precipitate from α-ferrite matrix in the deeper zone of the diffusion layer. These γ N laths are all twins, with their {111} twinning planes parallel to the lath axis, thus forming a characteristic "back-to-back" morphology. There are two types of γN lath. The first is a genuinely {111} twin, and γ N and α keep the accurate K-S relationship, and each γ N and α form a sharp and smooth γ N/α inter- face of {335}γN//{341}α, namely habit plane {335}fcc. The second is a pseudo-twin, with micro-twins {111} or faults formed within the two twin components. Localized lattice deformation (relaxation) seems to have occurred at the interfaces of the second type of γ N due to the formation of micro-twins or faults within the twin components. These micro-twins or faults make the orientation relationship (OR) between each of the γN and the α-matrix deviate from the accurate K-S OR, and the OR between two γ N twin components deviate from the genuine {111} twin relation- ship. In addition, the γ N/α interface of the second type of γ N is not as sharp or smooth as that of the first one.

关键词： austenite containing nitrogen, twins, steel 20, nitriding, composite chromizing

Cryodamage to plasma membrane integrity in head and tail regions of human sperm

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Asian Journal of Andrology 2000年第2期2卷 135-138页

作者： Wei-Jie ZHU Xue-Gao LIU center for Reproductive Immunology research, Jinan university, guangzhou 510632, china center for Reproductive Immunology research Jinan University Guangzhou 510632 China

Aim: To investigate the effect of cryopreservation on the plasma membrane integrity in the head and tail regions ofindividual sperm, and the relationship between intact cryopreserved sperm and its motility and zona-free hamster oocytepenetration rate. Methods: The eosin Y exclusion and the hypoosmotic swelling tests were combined to form a sin-gle test (HOS-EY test) to identify the spermatozoa with four types of membrane integrity. Results: After cryop-reservation, there was a marked decline in the percentage of spermatozoa with Type Ⅳ membrane integrity (head mem-brane intact/tail membrane intact), and a significant increase in those with Type Ⅰ (head membrane damaged/tail mem-brane damaged) and Type Ⅲ (head membrane damaged/tail membrane intact) membrane integrity (n = 50, P 25, r = 0.22, P > 0.05). Conclusion: (1) The HOS-EY test has the advan-tage of showing four patterns of membrane integrity in individual spermatozoon; (2) Cryopreservation causes a signifi-cant membrane rupture in the head and tail regions of spermatozoa; Type Ⅲ is the main transitional state of membranecryodamage; (3) Cryodamage to head and tail membrane may occur independently; the presence of an intact tail mem-brane does not necessarily indicate the intacmess of head membrane. (4) Intact membranes are closely related to post-thaw motility, but do not reflect the fertilizing potential.

关键词： spermatozoa cryopreservation cell membrane supravital staining hypoosmotic swelling test

In vitro characteristics of poly(lactic-co-glycolic acid)microspheres incorporating gelatin particles loading basic fibroblast growth factor

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Acta Pharmacologica Sinica 2006年第6期27卷 754-759页

作者： Shao-hong LI~(1,4)Shao-xi CAI~(1,3)Bing LIU~1 Kai-wang MA~1 Zhen-ping WANG~1 Xiao-kun LI~2 1 Key Laboratory for Biomechanical and Tissue engineering,State Ministry of Education,College of Bioengineerin,Chongqing university,Chongqing 400030,china 2 Gene Medicine engineering research center,Jinan university,guangzhou 510632,china Key Laboratory for Biomechanical and Tissue engineering State Ministry of Education College of Bioengineerin Chongqing University Chongqing China Gene Medicine engineering research center Jinan University Guangzhou China

Aim:To construct a sustained drug release system for basic fibroblast growthfactor(bFGF).With this special system,bFGF can be used to repair an injuredperipheral nerve,injured spinal cord,or as a carrier for other drugs that need to bereleased over a long ***:Microsphere composite was prepared byencapsulating bFGF into gelatin particles with poly(lactic-co-glycolic acid)(PLGA)as its *** encapsulation was conducted by a phase ***:The average diameter of the gelatin particle-PLGA microspherecomposite was 5-18μm,and bFGF-loading efficiency was up to 80.5%.The bFGFreleasing experiment indicated that this new composite system could release bFGFcontinuously and protect bFGF from ***:A modifiedapproach was successfully employed to develop a biodegradable system for sus-tained release of the drug of bFGF in vitro.

关键词： poly(lactic-co-glycolic acid) gelatin basic fibroblast growth factor microsphere delayed-action preparations

安装新型形状记忆合金阻尼器的古塔结构地震反应有限元分析

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振动与冲击 2012年第20期31卷 38-45页

作者：黄襄云王凤华广州大学工程抗震研究中心广州510405 广东建设职业技术学院广州510470

将设计的拉压型形状记忆合金(SMA)阻尼器,安装在古塔上,可同时减少古塔在水平地震和竖直地震作用下的响应。采用大型通用软件ANSYS对古塔安装和不安装SMA阻尼器结构分别进行有限元仿真,对结构的动力特性、水平地震反应和竖向地震反应进... 详细信息

将设计的拉压型形状记忆合金(SMA)阻尼器,安装在古塔上,可同时减少古塔在水平地震和竖直地震作用下的响应。采用大型通用软件ANSYS对古塔安装和不安装SMA阻尼器结构分别进行有限元仿真,对结构的动力特性、水平地震反应和竖向地震反应进行分析和对比,探讨SMA阻尼器的控制效果,分析结果与振动台试验数据进行比较,验证分析结果的可靠性。

关键词：拉压型形状记忆合金(SMA)阻尼器古塔有限元分析水平地震反应竖向地震反应