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Transactions of Nonferrous Metals society of China 2016年第9期26卷 2397-2403页

作者： p.KUMAR M.NATh A.GhOsh h.s.TRIpAThI Refractories Division CSIR–Central Glass and Ceramic Research Institute Academy of scientific and Innovative Research (Acs IR) CSIR–Central Glass & Ceramic Research Institute

Mullite–zirconia composites containing 20% zirconia（mass fraction） were prepared by reaction sintering route utilizing Indian coastal zircon flour and sillimanite beach sand. 4%-12% of CaO（mole fraction） with respect to zirconia was used as additive. The effect of additive on densification, microstructure as well as various mechanical and thermo-mechanical properties was studied. Incorporation of CaO reduced the densification temperature of the composites to 1550 ℃ compared to 1600 ℃（for CaO free samples）. CaO formed small amount of liquid phase（calcium aluminosilicate）, which facilitated sintering. Average grain size of the composites decreased up to 4% CaO addition, afterwards grain size increased with further addition of CaO. samples with 4% CaO exhibited ～225 Mpa of flexural strength, ～6 Mpa·m^1/2 of fracture toughness and significant improvement in thermal shock resistance. CaO stabilized the tetragonal zirconia phase and thus improved the mechanical properties.

关键词： reaction sintering mullite-zirconia composites flexural strength refractory

Gene therapy and erectile dysfunction： the current status

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Asian Journal of Andrology 2007年第1期9卷 8-15页

作者： David h. w. Lau sashi s. Kommu Emad J. siddiqui Cecil s. Thompson Robert J. Morgan Dimitri p. Mikhailidis Faiz h. Mumtaz Department of Urology Royal Free Hospital and University College Medical School University College London Royal Free Campus Rowland Hill Street London NW3 2QG UK Department of Clinical Biochemistry Royal Free Hospital and University College Medical School University College London Royal Free Campus Rowland Hill Street London NW3 2QG UK Department of surgery Royal Free Hospital and University College Medical School University College London Royal Free Campus Rowland Hill Street London NW3 2QG UK Department of Urology Chase Farm Hospital The Ridgeway Enfield EN2 8JL UK Institute of Cancer Research and The Royal Marsden hospitals Nhs Foundation Trust Surrey SM2 5PT UK

Current available treatment options for erectile dysfunction （ED） are effective but not without failure and/or side effects. Although the development of phosphodiesterase type 5 （pDE5） inhibitors （i.e. sildenafil, tadalafil and vardenafil） has revolutionized the treatment of ED, these oral medications require on-demand access and are not as effective in treating ED related to diabetic, post-prostatectomy and severe veno-occlusive disease states. Improvement in the treatment of ED is dependent on understanding the regulation of human corporal smooth muscle tone and on the identification of relevant molecular targets. Future ED therapies might consider the application of molecular technologies such as gene therapy. As a potential therapeutic tool, gene therapy might provide an effective and specific means for altering intracavernous pressure ＂on demand＂ without affecting resting penile function. however, the safety of gene therapy remains a major hurdle to overcome before being accepted as a mainstream treatment for ED. Gene therapy aims to cure the underlying conditions in ED, including fibrosis. Furthermore, gene therapy might help prolong the efficacy of the pDE5 inhibitors by improving penile nitric oxide bioactivity. It is feasible to apply gene therapy to the penis because of its location and accessibility, low penile circulatory flow in the flaccid state and the presence of endothelial lined （lacunar） spaces. This review provides a brief insight of the current role of gene therapy in the management of ED.

关键词： gene therapy nitric oxide synthase erectile dysfunction calcium-sensitive potassium channel vascular endothelial growth factor calcitonin gene-related peptide

Mitigating parametric instabilities in plasmas by sunlight-like lasers

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Matter and Radiation at Extremes 2021年第5期6卷 54-61页

作者： h.h.Ma X.F.Li s.M.weng s.h.Yew s.Kawata p.Gibbon Z.M.sheng J.Zhang Key Laboratory for Laser plasmas(MoE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFsA Shanghai Jiao Tong UniversityShanghai 200240China Graduate school of Engineering Utsunomiya UniversityYohtoh 7-1-2Utsunomiya 321-8585Japan Institute for Advanced simulation J¨ulich Supercomputing CentreForschungszentrum J¨ulich52425 J¨ulichGermany Centre for Mathematical plasma Astrophysics Katholieke Universiteit Leuven3000 LeuvenBelgium sUpA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUnited Kingdom Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

sunlight-like lasers that have a continuous broad frequency spectrum,random phase spectrum,and random polarization are formulated *** a sunlight-like laser beam consisting of a sequence of temporal speckles,the resonant three-wave coupling that underlies parametric instabilities in laser–plasma interactions can be greatly degraded owing to the limited duration of each speckle and the frequency shift between two adjacent *** wave coupling can be further weakened by the random polarization of such *** simulations demonstrate that the intensity threshold of stimulated Raman scattering in homogeneous plasmas can be doubled by using a sunlight-like laser beam with a relative bandwidth of∼1%as compared with a monochromatic laser ***,the hot-electron generation harmful to inertial confinement fusion can be effectively controlled by using sunlight-like laser *** drivers may be realized in the next generation of broadband lasers by combining two or more broadband beams with independent phase spectra or by applying polarization smoothing to a single broadband beam.

关键词： polarization scattering speckle

用RFLp方法研究陕西省主要小麦品种遗传多样性及其演变

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西北植物学报 1999年第2期19卷 208-213页

作者：朱列层唐国顺 hAZEN s p KIM h.s.w.RD R w 陕西省农科院小麦研究中心美国密西根州立大学作物土壤科学系韩国国家作物试验站

研究用ＲＦＬＰ方法，对我国主要小麦产区，陕西省４０年代以来广为种植的小麦品种的遗传多样性进行了研究，结果表明，占总带数２６．２％的ＨＩＮＤＩＩ酶的ＲＦＬＰ带具有遗传多态性。２４个小麦品种平均遗传相似系数为０．９４８。... 详细信息

研究用ＲＦＬＰ方法，对我国主要小麦产区，陕西省４０年代以来广为种植的小麦品种的遗传多样性进行了研究，结果表明，占总带数２６．２％的ＨＩＮＤＩＩ酶的ＲＦＬＰ带具有遗传多态性。２４个小麦品种平均遗传相似系数为０．９４８。５３．８％的探针显示了多态性。平均多态性信息含量指数为０．２５２。陕西省小麦品种遗传多样性以７０年代为最高，之后开始降低。

关键词：小麦 RFLp 遗传多样性

Direct acceleration of an annular attosecond electron slice driven by near-infrared Laguerre-Gaussian laser

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high power Laser science and Engineering 2021年第3期9卷 79-86页

作者： C.Jiang w.p.wang s.weber h.Dong Y.X.Leng R.X.Li Z.Z.Xu state Key Laboratory of high Field Laser physics and CAs Center for Excellence in Ultra-Intense Laser science Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China school of physical science and Technology ShanghaiTech UniversityShanghai 201210China University of Chinese Academy of sciences Beijing 100049China Institute of physics of the AsCR ELI-Beamlines Project18221 PragueCzech Republic school of science Xi’an Jiaotong UniversityXi’an 710049China

A new near-infrared direct acceleration mechanism driven by Laguerre-Gaussian laser is proposed to stably accelerate and concentrate electron slice both in longitudinal and transversal directions in ***-dimensional simulations show that a 2-μm circularly polarized LG_(p)^(l)(p=0,l=1,σ_(2)=-1)laser can directly manipulate attosecond electron slices in additional dimensions(angular directions)and give them annular structures and angular *** annular vortex attosecond electron slices are expected to have some novel applications such as in the collimation of antiprotons in conventional linear accelerators,edge-enhancement electron imaging,structured X-ray generation,and analysis and manipulation of nanomaterials.

关键词： annular electron slice direct laser acceleration Laguerre–Gaussian lasers near-infrared laser

环境催化中的陶瓷材料:应用与可能性(英文)

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催化学报 2012年第10期33卷 1611-1621页

作者： Nitin LABhsETwAR p.DOGGALI s.RAYALU R.YADAV T.MIsTUhAshI h.hANEDA Environmental Material Division National Environmental Engineering Research Institute(CSIR-NEERI) National Institute for Materials science(NIMs)

Environmental catalysis has been steadily growing because of the advances in its scientific and engineering aspects,as well as due to the new environmental challenges in the industrial *** development of new catalysts and materials is essential for new technologies for various environmental *** play important roles in various environmental applications including the identification,monitoring,and quantification of pollutants and their *** have important applications as sensors and photocatalysts,and they are extensively used as catalyst carriers and *** ceramics are being explored as catalysts for pollution control *** low cost,thermal and chemical stability,and capability of being tailored make them especially attractive for pollution control *** a wide variety of materials have been developed as catalyst supports,this area is still of interest with new or modified catalyst supports being frequently *** is of equal importance to develop new or modified processes for the loading of catalysts on specific *** like chemical looping combustion(CLC) and other catalytic combustion processes are raising the demands to a new *** have been working on the development of both new and modified support materials,including mesoporous materials without structural order for possible applications in CLC and other catalytic *** attempts have been made in the modification of conventional γ-Al2O3 and improved synthesis processes for supporting perovskite type *** research on environmental catalysis applications of ceramic materials and processes are also briefly discussed.

关键词： ceramics environmental catalysis perovskite catalyst carbonation catalyst support catalytic emission control chemical looping combustion

Rheological behavior of semi-solid TiB_2 reinforced Al composite

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Transactions of Nonferrous Metals society of China 2015年第9期25卷 2827-2832页

作者： s.ThADELA B.MANDAL p.DAs h.ROY A.K.LOhAR s.K.sAMANTA Near Net shape Manufacturing Technology Group CSIR-Central Mechanical Engineering Research Institute NDT & Metallurgy Group CSIR-Central Mechanical Engineering Research Institute

The rheological behavior of the semi-solid Ti B2 reinforced Al-Mg alloy composite slurry was investigated,which is required for the mould filling simulations during the semi-solid *** B2 reinforced in-situ Al-Mg alloy composite samples were remelted and subsequently brought to the semi-solid temperature regime within the heating chamber of a searle type *** order to understand the rheological behavior of composites,three different types of experiment were carried out,namely,steady state test,continuous cooling test and isothermal *** from that,the thixotropic nature of the slurry was confirmed from the obtained hysteresis loops during the *** results indicate that when isothermally held,the composite slurry exhibits pseudo-plasticity and shows shear-thinning behavior up to the shear rate of 1300 s^-1,and at higher shear rates（1300 s^-1）,it shows a shear thickening tendency,which is probably due to the agglomeration of non-deformable nano-Ti B2 *** pseudo-plastic behavior of the slurry was also estimated employing intermittent step changes of shear rate（shear jump test）.

关键词： rheology shear thinning in-situ nano-Ti B2 thixotropy shear thickening

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分子束外延高Mg掺杂GaN的发光特性

发光学报 1999年第2期20卷 148-151页

作者：宋航 park s h Kang T w Kim T w 中国科学院长春物理研究所

采用分子束外延技术在蓝宝石衬底上制备Ｍｇ掺杂的立方相ｐ－ＧａＮ，并对其不同温度下的光致发光光谱进行了研究．实验观察到高Ｍｇ掺杂ＧａＮ中施主受主对发光的反常温度行为．理论分析表明，高Ｍｇ掺杂ＧａＮ中施主受主对的发光受到... 详细信息

采用分子束外延技术在蓝宝石衬底上制备Ｍｇ掺杂的立方相ｐ－ＧａＮ，并对其不同温度下的光致发光光谱进行了研究．实验观察到高Ｍｇ掺杂ＧａＮ中施主受主对发光的反常温度行为．理论分析表明，高Ｍｇ掺杂ＧａＮ中施主受主对的发光受到陷阱与受主间竞争俘获非平衡空穴过程和空穴隧穿输运过程的影响．

关键词：光致发光隧穿效应分子束外延氮化镓掺镁

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激光熔敷的极限厚度

中国激光 1990年第3期17卷 185-186页

作者：陈新陶曾毅华中理工大学

本文在激光输出功率不变的条件下,系统地研究光斑尺寸,功率密度、扫描速度与熔敷极限厚度之间的关系,探讨影响激光熔敷的本质参数,指出激光熔敷的必要条件。一、实验条件为便于研究不同辐照条件下的最大熔敷厚度,特设计了一种坡形试样... 详细信息

本文在激光输出功率不变的条件下,系统地研究光斑尺寸,功率密度、扫描速度与熔敷极限厚度之间的关系,探讨影响激光熔敷的本质参数,指出激光熔敷的必要条件。一、实验条件为便于研究不同辐照条件下的最大熔敷厚度,特设计了一种坡形试样(见图1),其上开有坡形槽。激光束从粉末厚度为零的一端开始向厚度为h的一端扫描。基体材料选用16Mn钢,被熔敷的合金为NiCrsiB粉末。合金粉末用化学粘接剂调和,预置于坡形试样槽中。激光辐照时,用氩气进行保护。辐照工艺参数范围为p=2000w,D=2～5mm,V=2.8～25mm/s,

关键词：激光熔敷极限厚度光斑尺寸

沉默供体肝脏内Rps3基因减轻大鼠移植肝脏I/RI

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沉默供体肝脏内RPS3基因减轻大鼠移植肝脏I/RI

作者：陈新重庆医科大学

学位级别：硕士

目的核转录因子Kappa B（NF-κB）是在上世纪八十年代发现的一种能够与DNA特异性位点结合,并调控基因转录的蛋白质复合体。它与细胞中的绝大多数基因转录、表达密切相关,尤其是在肝移植后早期就发生的缺血再灌注损伤中,NF-κB起着举足... 详细信息

目的核转录因子Kappa B（NF-κB）是在上世纪八十年代发现的一种能够与DNA特异性位点结合,并调控基因转录的蛋白质复合体。它与细胞中的绝大多数基因转录、表达密切相关,尤其是在肝移植后早期就发生的缺血再灌注损伤中,NF-κB起着举足轻重的作用。核糖体蛋白s3（ribosomal protein s3,Rps3）最初被认为是核糖体的亚单位,参与蛋白质翻译。近年发现,它是NF-κB复合体的必需功能亚单位,在NF-κB介导的基因转录过程中具有关键性作用,这有可能成为NF-κB信号通路中又一突破性认识。本实验拟采用RNA干扰技术沉默供体肝脏内Rps3基因的表达,观察其对NF-κB活性及表达量的影响,以及对肝移植后早期缺血再灌注损伤（I/RI）的保护作用,探讨Rps3在肝移植后早期I/RI中的作用机制。方法构建以腺病毒（Ad）为载体的Rps3基因特异性短发夹RNA（shRNA）表达颗粒。将成年雄性sD大鼠随机分为三组,采用改良的Kamada袖套法于各组建立大鼠原位肝移植动物模型。将实验大鼠随机分为三组:（1）Rps3基因特异性短发夹RNA处理组（Ad-Rps3 -shRNA）、（2）空白腺病毒对照组（Ad-blank-control）、（3）生理盐水对照组（Ns-control）。于肝移植前48h分别用目标病毒表达颗粒、空白腺病毒载体、生理盐水经门静脉灌注三组供体大鼠肝脏;建立肝移植模型,后于肝脏恢复灌注3h、12h两个时间点各处死受体大鼠6只。经上腔静脉收集血液标本及相同部位肝脏组织标本备用。全自动生化分析仪检测血清ALT、AsT水平;光镜下双盲法以suzuki评分标准对各肝脏组织病理改变评分;ELIsA法检测各标本血浆炎症因子TNF-α、IL-1β、ICAM-1水平;qRT-pCR法检测各组大鼠肝脏组织中TNF-α、IL-1β、ICAM-1、Rps3 mRNA水平;western blot法检测肝脏组织中NF-κB蛋白水平;EMsA法检测肝脏组织中NF-κB蛋白活性。结果肝功指标:肝移植恢复灌注3h、12h Ad-Rps3-shRNA组ALT、AsT（725.9±67.3 U/L,1842.7±176.6 U/L;863.7±72.7 U/L ,1513.4±187.6 U/L）显著低于Ad-blank-control组（1736.5±173.7 U/L, 3232.6±273.1 U/L;1874.6±163.7 U/L,3149.1±282.6 U/L）与Ns-control组（1472.2±178.4 U/L,3347.6±293.5 U/L;2109.3±188.7 U/L,3662.4±269.6 U/L）,并且与这两组间相比差异有统计学意义（p ＜ 0.01）;Ad- blank-control组与Ns-control组间无显著差异（p ＞ 0.05）。肝脏组织病理改变评分:恢复灌注3h、12h Ad-Rps3-shRNA组suzuki评分（3.72±0.31,3.94±0.34）均低于Ad-blank-control组（7.93±0.63,8.18±0.66）与Ns-control组（8.22±0.61,8.25±0.69）,并且有显著差异（p ＜ 0.01）;Ad-blank-control组与Ns-control组间无显著差异（p ＞ 0.05）。血浆炎症因子水平、肝脏组织炎症因子及Rps3 mRNA水平以及NF-κB蛋白表达量和活性,在肝脏移植后恢复灌注3h、12h,同前面两个检测指标具有相似的变化倾向。结论本实验验证了通过门静脉灌注携带目标基因shRNA的慢病毒载体,可以达到有效转染的目的,并抑制目标基因的表达;在肝移植前通过门静脉灌注Ad-Rps3-shRNA,可以显著降低肝脏细胞NF-κB活性和表达量、降低炎症因子表达减轻肝细胞损伤,说明Rps3在NF-κB介导的肝移植后早期I/RI信号通路中发挥重要作用。由此可以得出结论:沉默供体肝脏内Rps3基因可以有效减轻肝移植后早期缺血再灌注损伤。

关键词： RNAi NF-κB 核糖体蛋白s3 肝移植 I/RI