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Formation of Ultrafine Apatite Fibers by Sol-gel/Electrospinning

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Chemical Research in Chinese Universities 2007年第3期23卷 366-369页

作者： DING Ya-mei YUAN Xiao-yan zhao Jin guo Wan-chun WANG Xiu-kui School of Materials Science and Engineering Tianjin University Tianjin 300072 P. R. China

Ultrafine apatite fibers were prepared by electrospinning of sol-gel precursor/poly（ vinyl pyrrolidone）（PVP） solutions followed by subsequent calcination. The as-electrospun and calcinated fibers were observed under a scanning electron microscope and an optical polarizing microscope. Results show that the morphology and the diameter of as-electrospun fibers strongly depend on the viscosity and the surface tension of sol-gel precursor/PVP solutions. After calcination, the smooth as-electrospun fibers shrink and the fiber diameter decreases because of the removal of the polymer. The chemical evolution upon the transformation of the precursor from a gel to the final apatite fibers was investigated by thermogravimetric-differenfial thermal analysis, X-ray diffraction, and Fourier transform infrared spectroscopy. It is thus suggested that the crystalline structure of the calcined fibers is largely influenced by the calcination temperature. After being calcined at 600 ℃, the apatite fibers with a diameter of about 280 nm containing β-tricalcium phosphate were obtained.

关键词： Apatite Ultrafine fiber Sol-gel Electrospinning

Comparison of α particle detectors based on single-crystal diamond films grown in two types of gas atmospheres by microwave plasma-assisted chemical vapor deposition

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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 703-712页

作者： yan-zhao guo Jin-long Liu Jiang-wei Liu Yu-ting Zheng Yun zhao Xiao-lu Yuan Zi-hao guo Li-fu Hei Liang-xian Chen Jun-jun Wei Jian-peng Xing Cheng-ming Li Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Optical and Electronic Materials Unit National Institute for Materials Science(NIMSIbaraki 305-0044Japan Key Laboratory of Microelectronic Device and Integration Technology Institute of Microelectronics of the Chinese Academy of SciencesBeijing 100029China

Chemical vapor deposition(CVD)-grown diamond films have been developed as irradiation-resistant materials to replace or upgrade current detectors for use in extreme radiation environments. However, their sensitivity in practical applications has been inhibited by space charge stability issues caused by defects and impurities in pure diamond crystal materials. In this study, two high-quality CVD-grown single-crystal diamond(SCD) detectors with low content of nitrogen impurities were fabricated and characterized. The intrinsic properties of the SCD samples were characterized using Raman spectroscopy, stereomicroscopy, and X-ray diffraction with the rocking curve mode, cathode luminescence(CL), and infrared and ultraviolet-visible-near infrared spectroscopies. After packaging the detectors, the dark current and energy resolution under α particle irradiation were investigated. Dark currents of less than 5 pA at 100 V were obtained after annealing the electrodes, which is comparable with the optimal value previously reported. The detector that uses a diamond film with higher nitrogen content showed poor energy resolution, whereas the detector with more dislocations showed poor charge collection efficiency(CCE). This demonstrates that the nitrogen content in diamond has a significant effect on the energy resolution of detectors, while the dislocations in diamond largely contribute to the poor CCE of detectors.

关键词： single-crystal diamond nitrogen impurity detector αparticle

The past and present of blast injury research in China

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Chinese Journal of Traumatology 2015年第4期18卷 194-200页

作者： yan zhao Yuan-guo Zhou Molecular Biology Center State Key Laboratory of Trauma Bums and Combined Injury Research Institute of Surgery and Daping Hospital Third Military Medical UniversityChongqing 400042 China

With the increasing incidence of blast injury, the research on its mechanisms and protective measures draws more and more attention. Blast injury has many characteristics different from general war injuries or trauma. For example, soldiers often have various degrees of visceral injury without significant surface damage, combined injuries and arterial air embolism. Researchers in China began to investigate blast injury later than the United States and Sweden, but the development is so fast that lots of achievements have been gained, including the development of biological shock tube, the mechanisms and characteristics of blast injury in various organs, as well as protective measures under special environments. This article reviews the past and current situation of blast injury research in China.

关键词： Blast injury Shock tube Blast wave

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章草名实考略

艺术百家 2007年第A02期23卷 63-68页

作者：赵彦国江苏省艺术研究院江苏南京210005

本文通过查考历史文献及书学界对章草之名的由来及其含义的不同说法,以及对由此产生的不同观点进行分析考证,从而廓清了章草一体,其得名缘于今草的产生之后,世人为了区别作为古体的章草和今草这两种不同形态体系的草书而作出的称谓上的... 详细信息

本文通过查考历史文献及书学界对章草之名的由来及其含义的不同说法,以及对由此产生的不同观点进行分析考证,从而廓清了章草一体,其得名缘于今草的产生之后,世人为了区别作为古体的章草和今草这两种不同形态体系的草书而作出的称谓上的区别。而章草之实则具体表现为其外部的书体特征:用笔多隶法,点画多波磔,结体多变化,字间不连属,草法有来历。

关键词：章草名实书法

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黄伯思《东观余论》成书及其版本考

艺术百家 2008年第3期24卷 103-107,119页

作者：赵彦国江苏省文化艺术研究院江苏南京210005

文献史料的收集整理是历史研究的重要手段,是正确认知历史真实的必要前提和关键所在。因此,对研究对象的相关史料进行科学梳理和考证,是不可缺少的基础环节。北宋黄伯思所著《东观余论》是在《法帖刊误》的基础上辑录平日关于书法的议... 详细信息

文献史料的收集整理是历史研究的重要手段,是正确认知历史真实的必要前提和关键所在。因此,对研究对象的相关史料进行科学梳理和考证,是不可缺少的基础环节。北宋黄伯思所著《东观余论》是在《法帖刊误》的基础上辑录平日关于书法的议论题跋而成的一部书学著作。此书纠正了当时颇为流行的官刻法帖《淳化阁帖》的诸多疏误,堪称最早从科学实证角度研究法书的扛鼎之作。本文运用文献学原理,对现存此书的成书及各种版本进行科学分类,考证论述其各版本产生的原由和成书时间,以及各种版本之间的相互关系和流变脉络,对深入研究黄伯思及其书学思想提供有力的史料支撑。

关键词：黄伯思《东观余论》成书版本

Severe Henoch-Schonlein purpura with infliximab forulcerative colitis

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World Journal of Gastroenterology 2015年第19期21卷 6082-6087页

作者： yang Song, yan-Hong Shi, Chong He, Chang-Qin Liu, Jun-Shan Wang, Yu-Jie zhao, yan-Min guo, Rui-Jin Wu, Xiao-Yue Feng, and Zhan-Ju Liu yang Song Yan-Hong Shi Chong He Chang-Qin Liu Jun-Shan Wang Yu-Jie Zhao Yan-Min Guo Rui-Jin Wu Xiao-Yue Feng Zhan-Ju Liu Department of Gastroenterology Shanghai Tenth People&#x02019 s Hospital Tongji University Shanghai 200072 China

Infliximab （IFX） is an anti-tumor necrosis factorchimeric antibody that is effective for treatment ofautoimmune disorders such as Crohn＇s disease andulcerative colitis （UC）. IFX is well tolerated with alow incidence of adverse effects such as infections,skin reactions, autoimmunity, and *** manifestations can appear as infusionreaction, vasculitis, cutaneous infections, psoriasis,eczema, and skin cancer. Here, we present anunusual case of extensive and sporadic subcutaneousecchymosis in a 69-year-old woman with severe UC,partial colectomy and cecostomy, following her initialdose of IFX. The reaction occurred during infliximabinfusion, and withdrawal of IFX led to gradual alleviationof her symptoms. We concluded that Henoch-Sch？nleinpurpura, a kind of leukocytoclastic vasculitis, mighthave contributed to the development of the *** the precise mechanisms of the vasculitis arestill controversial, such a case highlights the importanceof subcutaneous adverse effects in the management ofUC with IFX.

关键词： Henoch-Sch?nlein purpura Infliximab Vasculitis Subcutaneous ecchymosis Ulcerative colitis

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索膜接触对气承式膜结构雪荷载响应的影响

空间结构 2023年第1期29卷 75-82页

作者：闫啸林何艳丽赵彦国北京工业大学城市建设学部北京100124 世源科技工程有限公司北京100142

索网加劲气承式膜结构是典型的非线性柔性大跨空间结构,在雪作用下膜结构的破坏时有发生.对于索网加劲气承式膜结构的设计,通常将结构的索网与膜面简化为直接连接,忽略索网与膜面之间的摩擦和滑移,这种简化处理对大跨气承式膜结构的设... 详细信息

索网加劲气承式膜结构是典型的非线性柔性大跨空间结构,在雪作用下膜结构的破坏时有发生.对于索网加劲气承式膜结构的设计,通常将结构的索网与膜面简化为直接连接,忽略索网与膜面之间的摩擦和滑移,这种简化处理对大跨气承式膜结构的设计安全造成一定的隐患.本文利用ANSYS软件,将气承式膜结构的索与膜之间的摩擦滑移作为接触问题来考虑,建立接触模型,并对其进行初始形态分析和雪荷载作用下的响应分析.结果表明:当不考虑索膜接触滑移的影响时,索网对膜面的约束作用会被高估,计算得到膜面位移偏小,索网轴力偏大且容易出现应力集中的现象;考虑索膜接触分析时,索网对膜面约束能力下降,尤其是在不均匀雪荷载作用下,膜面位移明显增加,在局部雪荷载较大部位处的膜面和索网甚至会发生分离.因此需要考虑索膜接触滑移才能正确进行气承式膜结构在雪荷载下的响应分析,避免安全事故的发生.

关键词：气承式膜结构接触分析初始形态分析雪荷载分析

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盾构接收中钢套筒的受力变形特性与实测分析

岩土工程学报 2016年第11期38卷 1948-1956页

作者：廖少明门燕青赵国强徐伟忠同济大学地下建筑与工程系上海200092 同济大学岩土与地下工程教育部重点实验室上海200092 上海城建市政工程(集团)有限公司上海200065

富水砂性地层中在盾构接收时极易发生涌水、涌砂等事故,是盾构施工过程中的重大风险源之一。以上海轨道交通11号线龙华路站钢套筒接收工法盾构接收的工程实践为依托,首先采用数值模拟对钢套筒在盾构接收施工期间的受力和变形规律进行了... 详细信息

富水砂性地层中在盾构接收时极易发生涌水、涌砂等事故,是盾构施工过程中的重大风险源之一。以上海轨道交通11号线龙华路站钢套筒接收工法盾构接收的工程实践为依托,首先采用数值模拟对钢套筒在盾构接收施工期间的受力和变形规律进行了分析,然后通过钢套筒变形和防汛墙沉降的现场实测数据验证了钢套筒接收工法的可行性。结果表明,盾构推进使钢套筒结构的最大拉应力由后端板逐渐发展为筒体与地连墙连接部位的底部,筒体结构的环向应力为纵向应力的2～7倍、腰部以下的环向轴力增长明显、腰部累计变形将近10 mm,筒体底部的纵向应力增长明显、腰部的纵向弯矩变化明显。盾构推进导致筒体结构的底部外张、腰部内凹,筒体的径向变形由横鸭蛋变为竖鸭蛋并最终变为8字形,椭圆度达到3‰,但是盾构推进对后端板的应力和位移变化均不明显。筒体与地连墙间的接缝、钢套筒分块间的腰部接缝和底部接缝均是盾构接收中钢套筒结构受力和变形的薄弱部位。盾构完全进入钢套筒后,钢套筒结构的受力和变形最为不利。工程实测表明,采用钢套筒接收工法进行盾构接收安全、可行,但在工程实践中应重视腰部、底部和后端板位移实测数据的大的波动,规范施工操作并加强监控。

关键词：盾构隧道钢套筒力学行为现场实测

The neurotoxicity mediated by astrocytes involved in fragile X syndrome

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The neurotoxicity mediated by astrocytes involved in fragile...