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基于光子晶体的电磁吸收材料

红外与毫米波学报 2006年第2期25卷 143-146页

作者：高强银燕闫敦豹袁乃昌国防科学技术大学微波技术发展中心湖南长沙410073 国防科学技术大学理学院应用物理系湖南长沙410073

研究了微波光子晶体在雷达吸收材料上的应用,提出了一种应用PBG的新型雷达吸收材料.该种材料相对于传统的电Salisbury屏,具有厚度薄、重量轻的优点,而且吸收带宽取决于高阻表面的带隙,不再受到厚度为λ/4的限制.

关键词：雷达吸波材料光子晶体 Salisbury屏

Extraction of full energy peak of ^(137)Cs from in situ nai(Tl)gamma-ray spectrum

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Nuclear Science and Techniques 2016年第4期27卷 53-59页

作者： Le-Le Zhang Nan-Ping Wang bao-Chuan Li School of Geophysics and Information Technology China University of Geosciences

A Levenberg–Marquardt Gaussian fitting algorithm has been used for analyzing the overlap of three peaks(the 583-ke V peak of^(208)Tl, the 609-ke V peak of214 Bi, and the 662-ke V peak of^(137)Cs) using an in situ Na I(Tl) scintillation spectrometer. The algorithm, in addition,was compared with a genetic algorithm used for multiple deconvolution. The three fitted peak areas(583, 609, and662 ke V) were calculated from the measured gamma-ray spectra obtained from a simulation experiment in which a^(137) Cs source was buried at different soil depths(from 18 to38 cm). The application of the Levenberg–Marquardt algorithm yielded similar results compared to the genetic algorithm. A lack-of-fit test showed that the fitting is good when the instrumental noise levels were estimated from replicated analyses. The relative fitting error of the total net area and the residual standard deviation were within 5 %and 0.04, respectively, and the goodness of the fitting was better than 0.98. While the methods used in this paper give high performance, the results may lead to incorrect estimation when the signal-to-noise ratio is smaller than-30 d B. This study is useful for the determination of radioactive specific activity of^(137) Cs by in situ spectrometry.

关键词： 137Cs γ射线谱 Marquardt算法全能峰 Gaussian 拟合算法提取相对拟合误差

我国设施农业土壤质量退化特征与调控研究进展

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中国生态农业学报 2013年第7期21卷 787-794页

作者：史静张乃明包立云南农业大学资源与环境学院昆明650201

设施土壤质量退化已成为制约现代设施农业可持续发展的瓶颈。了解设施土壤退化成因与特征,并采取适宜的调控措施,对于促进设施农业持续健康发展具有重要意义。本文综述了国内目前设施农业土壤次生盐渍化、酸化、微生物区系破坏、养分失... 详细信息

设施土壤质量退化已成为制约现代设施农业可持续发展的瓶颈。了解设施土壤退化成因与特征,并采取适宜的调控措施,对于促进设施农业持续健康发展具有重要意义。本文综述了国内目前设施农业土壤次生盐渍化、酸化、微生物区系破坏、养分失调、有害物质积累等5个方面的退化特征与成因。简述了生物、农业、工程3类调控措施在改良设施土壤方面的应用研究进展。并且针对我国设施土壤质量研究中存在的关于探索形成原因和控制机理方面的研究少,原创性设施土壤改良与调控技术仍然十分缺乏,大尺度、长时间设施土壤质量演变的长期定位研究和动态监测工作十分滞后,有关设施土壤退化因素叠加效应与交互作用机理研究尚未涉及等问题,提出应将构建设施土壤质量标准体系,开展设施土壤质量退化演变机理以及拓展调控与改良技术,系统研究不同退化形式之间的相互作用,以及拓展新技术在设施农业土壤研究中的应用等4方面作为今后研究的重点。

关键词：设施农业土壤质量退化调控中国

c-Myc promotes tubular cell apoptosis in ischemia-reperfusion-induced renal injury by negatively regulating c-FLIP and enhancing FasL/Fas-mediated apoptosis pathway

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Acta Pharmacologica Sinica 2019年第8期40卷 1058-1066页

作者： Dan Xu bao Wang Pan-pan Chen Yan-zhe Wang nai-jun Miao Fan Yin Qian Cheng Zhuan-li Zhou Hong-yan Xie Li Zhou Jun Liu Xiao-xia Wang Hong Xue Wei Zhang Li-min Lu Department of Physiology and Pathophysiology School of Basic Medical SciencesShanghai Medical CollegeFudan University Department of Nephrology Shanghai Tong Ren HospitalShanghai Jiao Tong University School of Medicine

c-Myc plays an important role in cell proliferation,differentiation,and cell ***/Fas pathway is a key regulator of cell *** study was aimed to investigate the effects of c-Myc on the FasL/Fas pathway in ischemia-reperfusion(I/R)-induced renal *** were objected to bilateral renal ischemia for 60 min and reperfused for 24 or 48 ***-52 E cells were treated with hypoxia-reoxygenation(H/R)or *** was used to identify the distribution of *** apoptosis was assessed by TUNEL ***-c-Myc and recombinant pcDAN 3.0 were used to overexpress c-Myc and c-FLIP,*** assay and luciferase assay were used to detect the binding of c-Myc to c-FLIP *** I/R rats,c-Myc was increased significantly and mainly located in renal tubular epithelial cells;meanwhile,c-FLIP was decreased,cleaved caspase-8,cleaved caspase-3 and TUNEL-positive staining cells were *** of I/R rats with c-Myc inhibitor 10058-F4 significantly attenuated the decrease in c-FLIP,the increase in cleaved caspase-8,cleaved caspase-3,TUNEL-positive cells,Scr and BUN in I/R *** NRK-52 E cells,hypoxia and reoxygen induced the increase in c-Myc and decrease in *** and luciferase assay results indicated that cMyc binds to the promoter region of c-FLIP *** of c-Myc markedly decreased *** of c-FLIP inhibited the increase in cleaved caspase-8 and caspase-3 induced by *** indicated that c-Myc is increased in kidneys of I/R rats and negatively regulates the expression of c-FLIP,then enhanced FasL-induced cell apoptosis in I/R stress.

关键词： c-Myc c-FLIP Fas/Fas ischemia-reperfusion tubular cell apoptosis

Phenylpropanoid Derivatives Are Essential Components of Sporopollenin in Vascular Plants

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Molecular Plant 2020年第11期13卷 1644-1653页

作者： Jinp-Shi Xue baocai Zhang HuaDong Zhan Yong-Lin Lv Xin-Lei Jia TianHua Wang nai-Ying Yang Yu-Xia Lou Zai-bao Zhang Wen-Jing Hu Jinshan Gui Jianguo Cao Ping Xu Yihua Zhou Jin-Feng Hu Laigeng Li Zhong-Nan Yang Shanghai Key Laboratory of Plant Molecular Sciences College of Life SciencesShanghai Normal UniversityShanghai 200234China National Key Laboratory of Plant Molecular Genetics&CAS Center for Excellence in Molecular Plant Sciences Institute of Plant Physiology and EcologyChinese Academy of SciencesBeijing 200032China State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Crop Genetics and Germplasm Enhancement College of AgricultureNanjing Agricultural UniversityNanjing 210095China College of Life Science Xinyang Normal UniversityXinyangHenan 464000China Department of Natural Products Chemistry School of PharmacyFudan UniversityNo.826 Zhangheng RoadShanghai201203China

The outer wall of pollen and spores,namely the exine,is composed of sporopollenin,which is highly resistant to chemical reagents and *** this study,we demonstrated that phenylpropanoid pathway derivatives are essential components of sporopollenin in seed *** analyses showed that the autofluorescence of Lilium and Arabidopsis sporopollenin is similar to that of *** and NMR analyses of pollen from Lilium and Cryptomeria further revealed that the sporopollenin of seed plants contains phenylpropanoid derivatives,including p-hydroxybenzoate(p-BA),p-coumarate(p-CA),ferulate(FA),and lignin guaiacyl(G)*** phenylpropanoid pathway is expressed in the tapetum in Arabidopsis,consistent with the fact that the sporopollenin precursor originates from the *** germination and comet assays showed that this pathway plays an important role in protection of pollen against UV *** the pteridophyte plant species Ophioglossum vulgatum and Lycopodium clavata,phenylpropanoid derivatives including p-BA and p-CA were also detected,but G units were *** together,our results indicate that phenylpropanoid derivatives are essential for sporopollenin synthesis in vascular *** addition,sporopollenin autofluorescence spectra of bryophytes,such as Physcomitrella and Haplocladium,exhibit distinct characteristics compared with those of vascular plants,indicating the diversity of sporopollenin among land plants.

关键词： sporopollenin pollen cell wall phenylpropanoid pathway

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惰性电极上电合成聚噻吩膜的分形特征研究

材料科学与工艺 2009年第1期17卷 8-12页

作者：梁成浩陈婉黄乃宝徐晶大连海事大学机电与材料工程学院辽宁大连116026 大连理工大学化工学院辽宁大连116012

为认识和建立聚噻吩膜(PBT)形态的变化与膜电化学性能及电化学合成条件之间的联系,采用灰度法和交流阻抗法对不同电化学条件下聚噻吩膜的分维值进行描述.研究表明,电化学合成的PBT膜具有统计分形特征,薄膜的分维值小,而厚膜的分维值大,... 详细信息

为认识和建立聚噻吩膜(PBT)形态的变化与膜电化学性能及电化学合成条件之间的联系,采用灰度法和交流阻抗法对不同电化学条件下聚噻吩膜的分维值进行描述.研究表明,电化学合成的PBT膜具有统计分形特征,薄膜的分维值小,而厚膜的分维值大,薄膜与厚膜具有不同的分形特征.在0～0.6V电位范围内,随着外加电位的正移,PBT膜的分维值由2.101增加到2.304,而反应电阻则由4152Ω·cm2降至3.585Ω·cm2,验证了PBT膜具有由绝缘态转变为氧化态的开关行为.随着电化学合成时间的增加,电极上PBT膜的分维值在7min时出现一个极小值2.060,说明紧靠电极表面的PBT薄层结构规整.

关键词：电聚合聚噻吩膜分形交流阻抗

Liver Cirrhosis and Intestinal Bacterial Translocation

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国际感染病学（电子版） 2014年第3期3卷 133-138页

作者： Tao Lan bao-chun Chen Li-ping Fu Zhi-juan Li Xiang-jun Wu nai-qiang Cui Graduate School of Tianjin University of Traditional Chinese Medicine Cangzhou People's Hospital Affiliated to Southern Medical University

Intestinal barrier dysfunction, facilitating translocation of bacteria and bacterial products, plays an important role in the pathophysiology of liver cirrhosis and its complications. Intestinal defense system including microbial barrier, immunologic barrier, mechanical barrier, chemical barrier, plays an important role in the maintenance of intestinal function. Under normal circumstances, the intestinal barrier can prevent intestinal bacteria through the intestinal wall from spreading to the body. Severe infection, trauma, shock, cirrhosis, malnutrition, immune suppression conditions, intestinal bacteria and endotoxin translocation, can lead to multiple organ dysfunction. The intestinal microflora is not only involved in the digestion of nutrients, but also in local immunity, forming a barrier against pathogenic microorganisms. The derangement of the gut microflora may lead to microbial translocation, defined as the passage of viable microorganisms or bacterial products from the intestinal lumen to the mesenteric lymph nodes and other extraintestinal sites. In patients with cirrhosis, primary and intestinal flora imbalance, intestinal bacterial overgrowth, intestinal mucosal barrier dysfunction, endotoxemia is associated with weakened immunity.

关键词： Cirrhosis Intestinal barrier Bacterial translocation Endotoxemia

微弧氧化/溶胶-凝胶法制备镁基羟基磷灰石复合涂层及性能研究

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功能材料 2014年第14期45卷 14123-14128页

作者：贾理男梁成浩段峰黄乃宝大连海事大学交通运输装备与海洋工程学院辽宁大连116026 大连市轻工业学校辽宁大连116023

采用微弧氧化/溶胶-凝胶工艺,在AZ91D镁合金表面制备羟基磷灰石涂层,并研究了镁基羟基磷灰石涂层的形貌、结构、组成及其电化学性能。结果表明,微弧氧化电流密度为0.5A/cm2时,采用溶胶-凝胶法制备的涂层表面均匀、多孔且紧密;Ca/P摩尔比... 详细信息

采用微弧氧化/溶胶-凝胶工艺,在AZ91D镁合金表面制备羟基磷灰石涂层,并研究了镁基羟基磷灰石涂层的形貌、结构、组成及其电化学性能。结果表明,微弧氧化电流密度为0.5A/cm2时,采用溶胶-凝胶法制备的涂层表面均匀、多孔且紧密;Ca/P摩尔比(1.70)高于溶胶配制的比例(1.67),是由于CO2-3替代了磷灰石晶格中的PO3-4所致。电化学测试结果表明,微弧氧化电流密度为0.5A/cm2时,羟基磷灰石涂层在Hank’s溶液中具有较低的腐蚀电流密度、较高的总阻抗和腐蚀电阻;浸泡实验表明该涂层有利于诱导磷灰石涂层的形成。

关键词：微弧氧化溶胶-凝胶法 AZ91D镁合金羟基磷灰石

溶胶-凝胶法制备的Al_2O_3涂层及其对γ-TiAl合金的高温氧化防护

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中国有色金属学报 2009年第8期19卷 1488-1492页

作者：任保轶张学军冯乃祥高枫东北大学材料与冶金学院沈阳110004 沈阳化工学院应用化学学院沈阳110142

以异丙醇铝(Al(OC3H7)3)为原料,采用溶胶-凝胶法在γ-TiAl基合金表面制备Al2O3涂层。以空白样品做对照,研究涂层的作用机制以及涂层对γ-TiAl基合金1 000℃高温氧化行为的影响。结果表明:采用浸涂工艺制备的涂层表面均匀、无裂纹,主要由... 详细信息

以异丙醇铝(Al(OC3H7)3)为原料,采用溶胶-凝胶法在γ-TiAl基合金表面制备Al2O3涂层。以空白样品做对照,研究涂层的作用机制以及涂层对γ-TiAl基合金1 000℃高温氧化行为的影响。结果表明:采用浸涂工艺制备的涂层表面均匀、无裂纹,主要由γ-Al2O3相组成,厚度约为0.8μm;等温氧化110 h后,空白试样和Al2O3涂层试样的氧化抛物线速率常数分别为4.85×10-12和3.31×10-13 g2/(cm4.s),涂层明显提高合金的抗氧化能力及抗循环氧化能力;空白样品上形成的氧化膜出现分层现象,而在涂层样品的Al2O3涂层中存在金红石型TiO2和α-Al2O3混合物。

关键词： Al2O3涂层溶胶-凝胶法 γ-TiAl基合金高温氧化