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Evolution in physiochemical and cloud condensation nuclei activation properties of crop residue burning particles during photochemical aging
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作者 Yan Ma Chao Chen +4 位作者 Junfeng Wang Youling Jiang Zewen Zheng Hui Chen Jun Zheng 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第3期43-53,共11页
As a main form of biomass burning in agricultural countries, crop residue burning is a significant source of atmospheric fine particles. In this study, the aging of particles emitted from the burning of four major cro... As a main form of biomass burning in agricultural countries, crop residue burning is a significant source of atmospheric fine particles. In this study, the aging of particles emitted from the burning of four major crop residues in China was investigated in a smog chamber.The particle size distribution, chemical composition and cloud condensation nuclei(CCN)activity were simultaneously measured. The properties of crop residue burning particles varied substantially among different fuel types. During aging, the particle size and mass concentration increased substantially, suggesting condensational growth by formation of secondary aerosols. The particle composition was dominated by organics. Aging resulted in considerable enhancement of organics and inorganics, with enhancement ratios of 1.24–1.44 and 1.33–1.76 respectively, as well as a continuous increase in the oxidation level of organics. Elevated CCN activity was observed during aging, with the hygroscopicity parameter κ varying from 0.16 to 0.34 for fresh particles and 0.19 to 0.40 for aged particles.Based on the volume mixing rule, the hygroscopicity parameter of organic components(κorg) was derived. κorgexhibited an increasing tendency with aging, which was generally consistent with the tendency of the O:C ratio, indicating that the oxidation level was related to the hygroscopicity and CCN activity of organic aerosols from crop residue burning. Our results indicated that photochemical aging could significantly impact the CCN activation of crop burning aerosols, not only by the production of secondary aerosols, but also by enhancing the hygroscopicity of organic components, thereby contributing to the aerosol indirect climate forcing. 展开更多
关键词 Crop residue BURNING AGING Cloud CONDENSATION NUCLEI activity HYGROSCOPICITY Organic aerosol
Prediction of the Distribution of Perennial Cultivated Grasses in the Northwest Sichuan Plateau, China under Climate Change 预览
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作者 Bin Guo San Wang +2 位作者 Chao Chen Mingtian Wang Tingting Li 《地球科学和环境保护期刊(英文)》 2019年第10期95-111,共17页
In order to determine the threshold and potential distribution of climatic conditions for perennial cultivated grasses in the Northwest plateau of Sichuan, China, the niche model is used to simulate the main climatic ... In order to determine the threshold and potential distribution of climatic conditions for perennial cultivated grasses in the Northwest plateau of Sichuan, China, the niche model is used to simulate the main climatic factors affecting the distribution of perennial cultivated grasses, and to predict the current and future climate change prospects. The results show that: 1) Wet index, accumulated temperature, isothermal, and annual average temperature range are the four major climatic factors affecting the distribution of perennial cultivated grasses in the Northwest Sichuan Plateau. 2) Model training and prediction data can be achieved well under the appropriate range of major climatic factors. 3) Under the background of climate warming, from now to 2080, the potential distribution of perennial cultivated grasses in the Northwest plateau of Sichuan, China will increase. The study aims to provide scientific decision-making basis for maintaining grassland ecosystem stability and promoting desertification management and even industrial restructuring of agriculture and animal husbandry. 展开更多
关键词 Clmatei Change MAXENT Model DOMINANT Factor PERENNIAL CULTIVATED Grasses NORTHWEST SICHUAN Plateau
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窄线宽半导体激光器研究进展
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作者 郎兴凯 贾鹏 +7 位作者 陈泳屹 秦莉 梁磊 陈超 王玉冰 单肖楠 宁永强 王立军 《中国科学:信息科学》 CSCD 北大核心 2019年第6期649-662,共14页
人类社会正迎来智能出行时代,智能汽车的发展对高精度雷达探测技术的要求越来越高,而新型全固态激光雷达,具有分辨率高、抗有源干扰能力强、体积小、重量轻、成本低等优势,可满足未来智能汽车的需求.窄线宽半导体激光器作为全固态激光... 人类社会正迎来智能出行时代,智能汽车的发展对高精度雷达探测技术的要求越来越高,而新型全固态激光雷达,具有分辨率高、抗有源干扰能力强、体积小、重量轻、成本低等优势,可满足未来智能汽车的需求.窄线宽半导体激光器作为全固态激光雷达的理想光源,其技术的进步与发展能大幅提升全固态激光雷达的实用化进程.本文详细介绍了当前国际上窄线宽半导体激光技术及发展现状,并分析讨论了各种窄线宽激光器的设计思路、关键技术及光学特性,最后展望了窄线宽半导体激光器的发展前景. 展开更多
关键词 半导体激光器 窄线宽 内腔光反馈技术 外腔光反馈技术 全固态激光雷达
飞秒激光诱导钛表面可控微纳结构用于水下气泡操纵
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作者 张亦元 焦云龙 +4 位作者 陈超 胡衍雷 李家文 肖轶 吴东 《科学通报》 EI CAS CSCD 北大核心 2019年第12期1296-1302,共7页
针对典型金属材料钛,利用自主搭建的飞秒激光振镜扫描加工系统,加工了具有特定形貌特征的多尺度微纳结构.在此基础上对多尺度微纳结构的可逆润湿性及水下气泡操纵特性进行了实验探究,并从微观界面化学的角度阐释了可逆润湿性的调谐机理... 针对典型金属材料钛,利用自主搭建的飞秒激光振镜扫描加工系统,加工了具有特定形貌特征的多尺度微纳结构.在此基础上对多尺度微纳结构的可逆润湿性及水下气泡操纵特性进行了实验探究,并从微观界面化学的角度阐释了可逆润湿性的调谐机理.研究结果表明:在飞秒激光烧蚀挤压作用下,钛表面诱导的多尺度微纳结构对原始表面的润湿性具有放大效应,固液接触角减小,水下气泡接触角增大;在辅助加热条件下,固液接触角增大,水下气泡接触角同时减小,气泡在表面完全铺展;随后将超疏水表面置于紫外灯下曝光,多尺度微纳结构上的液体接触角又开始减小,并最终实现了超疏水到超亲水性以及水下超亲气到超疏气的可逆调谐.另外,液体接触角与水下气泡接触角的可逆调谐特性呈现相反的变化趋势,这与固液气三相接触线的移动机制密切相关.本文对实现钛表面微纳结构设计与调控,提高具有可逆润湿性的金属表面在水下气泡操纵与收集,以及污水处理等领域的应用都具有重要意义. 展开更多
关键词 飞秒激光 多尺度微纳结构 超疏水 可逆润湿性 气泡操纵
Development of HL-2M data integration and acquisition system for magnetic diagnostics
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作者 潘银海 范伟伟 +1 位作者 陈超 阴泽杰 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第10期77-82,共6页
Magnetic measurement and diagnostics are critical for the operation of magnetic confinement experimental facilities and plasma analysis, while differential signals are mostly detected by a detector. For this, we have ... Magnetic measurement and diagnostics are critical for the operation of magnetic confinement experimental facilities and plasma analysis, while differential signals are mostly detected by a detector. For this, we have developed and designed a stable and reliable data integration system for HL-2M magnetic measurement and magnetic diagnostics. The system will be used for realtime control of HL-2M after the construction of HL-2M is completed. The system is built based on the PXI platform, and the software system is based on the LABVIEW platform. Key technologies realized by the system primarily include drift compensation, pulse data acquisition technology, multi-threading processing technology and transmission control communication protocol. Trials of the system were successfully carried out on HL-2A, and the results showed that the system could fully meet the construction needs of HL-2M. 展开更多
关键词 DIGITAL INTEGRATION DIFFERENTIAL INTEGRATION MAGNETIC SIGNALS
有机高分子纳米光热剂在体内疾病诊疗中的应用(英文)
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作者 欧翰林 李军 +3 位作者 陈超 高贺麒 薛雪 丁丹 《中国科学:材料科学(英文版)》 CSCD 2019年第11期1740-1758,共19页
有机高分子纳米光热剂具有生物安全性高、易于功能化修饰和诊疗一体化等优点,因而被广泛应用于生物医学领域.本综述主要总结了近年来有机高分子纳米光热剂在体内光声成像和光热治疗中的应用进展,并重点讨论了通过调控有机高分子纳米光... 有机高分子纳米光热剂具有生物安全性高、易于功能化修饰和诊疗一体化等优点,因而被广泛应用于生物医学领域.本综述主要总结了近年来有机高分子纳米光热剂在体内光声成像和光热治疗中的应用进展,并重点讨论了通过调控有机高分子纳米光热剂的光物理性质以实现增强的体内光声成像和光热治疗效果的传统策略和新兴机理.希望本综述为开发更多具有优异体内光声成像和光热治疗效果的有机高分子纳米光热剂提供借鉴,以进一步推动肿瘤等重大疾病的早期诊断和治疗. 展开更多
关键词 PHOTOTHERMAL agent PHOTOACOUSTIC imaging PHOTOTHERMAL therapy SEMICONDUCTING polymer NANOPARTICLE
Cloning and Ectopic Expression of <i>ScYCF</i>1 Gene from <i>Saccharomyces cerevisiae</i>in Cotton 预览
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作者 Min Mu Na Shu +8 位作者 Xuke Lu Xiugui Chen Shuai Wang Junjuan Wang Delong Wang Weili Fan Lixue Guo Chao Chen Wuwei Ye 《农业科学(英文)》 2018年第1期53-68,共16页
Yeast cadmium factor 1 (YCF1), is a member of the ATP-binding cassette (ABC) transporter family. To explore the functions of YCF1 of Saccharomyces cerevisiae (ScYCF1) in the cotton, ScYCF1 was cloned from Saccharomyce... Yeast cadmium factor 1 (YCF1), is a member of the ATP-binding cassette (ABC) transporter family. To explore the functions of YCF1 of Saccharomyces cerevisiae (ScYCF1) in the cotton, ScYCF1 was cloned from Saccharomyces cerevisiae As2.375, with the full-length of 4548 bp. The bioinformatics analysis revealed that the largest component of ScYCF1 protein is leucine (12%). ScYCF1 is alkaline and positive charged, stable, and hydrophilic protein. The predictive secondary structure is mainly composed of α-helix areas, random coils and β-sheets. We constructed the pBI121-ScYCF1:GFP infusion expression vector and verified it by enzyme ingestion. The transient expression results of cotton pollen showed that the green fluorescence phenomenon of three kinds of upland cotton pollen significantly increased after transforming ScYCF1. The salt sensitive material upland cotton CCRI12 was transformed in vivo simultaneously, and the germination ability of trans-ScYCF1-gene T0 seeds was much better than the acceptor material CCRI12 under the stress of 100 mM NaCl saline solution. According to the gene nucleotide sequences, four pairs of primers were designed for molecular detection of T0 generation, and the sequencing results of PCR products of four specific primers evidence that the transgene is successful. Salt tolerance analysis of leaf discs of identified transgenic cotton showed that the chlorophyll content of leaf discs of transgenic cotton was higher than the content of the control cotton under salt stress. ScYCF1 gene was cloned and introduced into cotton, showing that ScYCF1 plays an important role in improving the salt tolerance of cotton. 展开更多
关键词 SACCHAROMYCES CEREVISIAE ScYCF1 UPLAND COTTON Pollen Instantaneous Expression Molecular Detection
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血清抗凝血酶Ⅲ、纤维蛋白原对高危NSTE-ACS患者的评估价值 预览
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作者 徐通达 陈超 +4 位作者 李东野 张延斌 陈军红 宣皓晨 王超凡 《中国现代医学杂志》 2018年第18期50-55,共6页
目的探讨非ST段抬高型急性冠状动脉综合征(NSTE-ACS)患者血清抗凝血酶Ⅲ(AT-Ⅲ)、纤维蛋白原(FIB)水平对高危患者的评估价值。方法选取2015年1月-2016年12月该院根据临床特征和冠状动脉造影(CAG)确诊为NSTE-ACS患者280例为实验... 目的探讨非ST段抬高型急性冠状动脉综合征(NSTE-ACS)患者血清抗凝血酶Ⅲ(AT-Ⅲ)、纤维蛋白原(FIB)水平对高危患者的评估价值。方法选取2015年1月-2016年12月该院根据临床特征和冠状动脉造影(CAG)确诊为NSTE-ACS患者280例为实验组,依据全球急性冠状动脉事件注册(GRACE)评分将实验组分为低危组47例(≤108分)、中危组106例(109~140分)、高危组127例(〉140分);根据临床特征和CAG排除NSTE-ACS患者40例作为对照组。分析AT-Ⅲ、FIB水平在不同组间的差异和与GRACE评分的相关性以及GRACE评分的独立影响因素;受试者工作曲线(ROC)分析AT-Ⅲ、FIB对高危NSTE-ACS的预测价值,Logistic多因素回归分析高危NSTE-ACS的预测指标。结果实验组AT-Ⅲ水平低于对照组,而FIB水平高于对照组(P〈0.05);AT-Ⅲ水平与GRACE评分负相关(P〈0.05),FIB水平与GRACE评分正相关(P〈0.05);AT-Ⅲ、FIB是GRACE评分和高危风险的预测因素(P〈0.05)。ROC分析显示:AT-Ⅲ、FIB ROC曲线面积为0.797、0.756(P〈0.05);最佳界值分别为85.50和4.03;敏感性分别为69%和66%;特异性分别为91%和93%。结论 NSTE-ACS患者血清AT-Ⅲ、FIB水平与其危险分层密切相关,是评估危险分层和高危风险的预测因子。 展开更多
关键词 非ST段抬高型急性冠状动脉综合征 GRACE评分 血清抗凝血酶Ⅲ 纤维蛋白原 冠状动脉造影
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利用CRISPR/Cas9双基因敲除系统初步解析大豆GmSnRK1.1和GmSnRK1.2对ABA及碱胁迫的响应 预览 被引量:2
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作者 李慧卿 陈超 +4 位作者 陈冉冉 宋雪薇 李佶娜 朱延明 丁晓东 《遗传》 CSCD 北大核心 2018年第6期496-507,共12页
蔗糖非发酵相关激酶(sucrose non-fermenting related protein kinases,Sn RKs)是广泛存在于植物中的一类Ser/Thr蛋白激酶,在植物的生长、发育、代谢和抗逆等方面具有重要调节作用。大豆(Glycine max L.)基因组中含有4个Sn RK1同源... 蔗糖非发酵相关激酶(sucrose non-fermenting related protein kinases,Sn RKs)是广泛存在于植物中的一类Ser/Thr蛋白激酶,在植物的生长、发育、代谢和抗逆等方面具有重要调节作用。大豆(Glycine max L.)基因组中含有4个Sn RK1同源基因,其中GmSnRK1.1和GmSnRK1.2为两个主要表达基因,可能参与大豆多种抗逆途径。为解析大豆GmSnRK1.1和GmSnRK1.2对ABA及碱胁迫的响应,本研究构建了双靶点CRISPR载体定向敲除GmSnRK1.1和GmSnRK1.2基因,利用发根农杆菌(Agrobacterium rhizogenes)介导大豆遗传转化,获得双基因敲除突变体毛状根,经测序鉴定双基因突变率为48.6%;同时,利用实验室前期构建的植物超量表达载体获得超量表达GmSnRK1基因大豆毛状根。经25μmol/L ABA处理15 d,对照组和超量表达毛状根的生长受到明显抑制,其根长与根鲜重均显著低于双基因敲除突变体毛状根;经50 mmol/L Na HCO3处理15 d,对照组和双基因敲除突变体毛状根的生长受到明显抑制,其根长与根鲜重均显著低于超量表达毛状根。本研究建立的CRISPR/Cas9系统能够有效地对大豆进行GmSnRK1.1和GmSnRK1.2双基因敲除,基因敲除突变降低了植物对ABA的敏感性及对碱胁迫的耐性,研究结果初步说明Sn RK1激酶在植物响应非生物胁迫中具有重要作用。 展开更多
关键词 大豆 CRISPR/Cas9 GmSnRK1.1 GmSnRK1.2 ABA信号 碱胁迫
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分形花及其网络上的平均测地距离
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作者 王松静 赵璐铭 +1 位作者 陈超 奚李峰 《数学学报》 CSCD 北大核心 2018年第5期857-864,共8页
借助圆周映射计算距离函数在自相似测度上的积分,本文利用自相似测度得到分形花上的平均测地距离,并将此结果应用于分形花网络.
关键词 分形 自相似集 自相似测度 测地距离
超重/肥胖2型糖尿病患者夜间皮质醇水平和微血管并发症的相关性分析
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作者 傅奥博 谢雨婷 +14 位作者 何斌斌 杨琳 罗说明 张晶晶 肖扬 王臻 刘玮 冯琼 超晨 杨亚玲 盛志峰 苏欣 彭依群 李霞 周智广 《中华内分泌代谢杂志》 CSCD 北大核心 2018年第10期834-838,共5页
目的 在超重或肥胖的2型糖尿病患者中探讨夜间血清皮质醇水平和糖尿病微血管并发症的相关关系。方法 检测316例超重或肥胖的2型糖尿病患者的夜间0点血清皮质醇,按照不同的皮质醇水平分组,比较各组间糖尿病微血管并发症的状况。所有夜... 目的 在超重或肥胖的2型糖尿病患者中探讨夜间血清皮质醇水平和糖尿病微血管并发症的相关关系。方法 检测316例超重或肥胖的2型糖尿病患者的夜间0点血清皮质醇,按照不同的皮质醇水平分组,比较各组间糖尿病微血管并发症的状况。所有夜间血清皮质醇>50nmol/L者行过夜小剂量地塞米松抑制试验,排除亚临床库欣综合征。用化学发光免疫法检测血清皮质醇,同时检查患者发生糖尿病肾病(Diabetic nephropathy,DN)、糖尿病视网膜病变(Diabetic retinopathy,DR)、糖尿病周围神经病变(Diabetic peripheral neuropathy,DPN)的情况。结果 (1)在超重或肥胖的2型糖尿病患者中,DN发生比例在低、中、高皮质醇组逐渐升高,分别为13.3%、27.7%、44.2%,3组比较差异有统计学意义(P〈0.05)。与低皮质醇组相比,中、高皮质醇组发生DR的比例升高(40.6%和1147.7%对22.7%,均P〈0.01)。高皮质醇组发生DPN的比例高于低皮质醇水平组(60.5%对38.7%,P〈0.01);(2)有糖尿病微血管并发症的患者夜间血清皮质醇水平较无并发症者高[(136.87±105.78对97.55±93.48)nmol/L,P〈0.01];与仅合并单个并发症者相比。合并有多个并发症的患者夜间皮质醇水平较高[(151.66±114.54对117.69±90.26)nmol/L,P〈0.05];(3)单因素相关分析显示,除了女性、年龄、糖尿病病程、空腹血糖以外,高皮质醇水平也是发生2型糖尿病微血管并发症的危险因素。多因素相关分析显示,经过校正病程、空腹血糖、HbA1c使用胰岛素治疗等因素后,夜间0点皮质醇水平仍是发生糖尿病微血管并发症的危险因素(P=0.013)。结论 在超重或肥胖的2型糖尿病患者中,夜间皮质醇水平升高可能是糖尿病伴发微血管并发症的危险因素。 展开更多
关键词 超重 肥胖 糖尿病 2型 皮质醇 糖尿病微血管并发症
熔体流淌条件对橡胶生胶燃烧行为的影响 预览
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作者 王勇 张筱毓 +2 位作者 陈超 杨力华 康文东 《高分子材料科学与工程》 CSCD 北大核心 2018年第11期44-48,共5页
为探究熔体流淌条件对橡胶生胶燃烧行为的影响,文中选取天然橡胶(NR)、顺丁橡胶(BR)和丁苯橡胶(SBR)为研究对象,在自制熔体流淌火灾试验装置上进行燃烧实验,得到质量损失速率(MLR)、气相温度、池火面积等数据。研究结果表明,流淌燃烧条... 为探究熔体流淌条件对橡胶生胶燃烧行为的影响,文中选取天然橡胶(NR)、顺丁橡胶(BR)和丁苯橡胶(SBR)为研究对象,在自制熔体流淌火灾试验装置上进行燃烧实验,得到质量损失速率(MLR)、气相温度、池火面积等数据。研究结果表明,流淌燃烧条件下3种橡胶的MLR峰值、气相温度和燃烧速度均高于不流淌燃烧条件的,且燃烧时间缩短为不流淌燃烧时的一半,这与熔体流淌扩大了池火的面积有关。流淌条件下橡胶的MLR与池火面积呈线性关系,达到相同MLR时的池火面积大小顺序为NR>SBR>BR。气相温度峰值大小顺序为BR>NR>SBR,这与橡胶样品的平均有效燃烧热(AEHC)、MLR峰值和池火面积有关。 展开更多
关键词 橡胶 熔体 流淌燃烧 池火
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Dipole Polarizabilities of the Ground States for Berylliumlike Ions
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作者 陈超 苟秉聪 《理论物理通讯:英文版》 SCIE CAS CSCD 2018年第12期765-770,共6页
Dipole polarizabilities of the ground states for berylliumlike ions with nuclear charge Z = 4 to 10 are calculated by using the Rayleigh-Ritz variational method with multiconfiguration interaction wave functions. The ... Dipole polarizabilities of the ground states for berylliumlike ions with nuclear charge Z = 4 to 10 are calculated by using the Rayleigh-Ritz variational method with multiconfiguration interaction wave functions. The representative models of convergence are listed and compared with other theoretical data for nuclear charge Z = 4 to6. The present dipole polarizabilities are in good agreement with previous accurate theoretical values available in the literature. For results with greater nuclear charge number, the present calculations may provide benchmarked data for future theoretical and experimental studies. Dynamic dipole polarizabilities of the ground state for the beryllium atom at selected frequencies are also calculated and compared with other theoretical values in the literature. 展开更多
关键词 DIPOLE POLARIZABILITY berylliumlike IONS variation-perturbation METHOD
Helicobacter pylori infection with intestinal metaplasia: An independent risk factor for colorectal adenomas 预览
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作者 Ye Yan Yi-Na Chen +5 位作者 Qian Zhao Chao Chen Chun-Jing Lin Yin Jin Shuang Pan Jian-Sheng Wu 《世界胃肠病学杂志:英文版》 SCIE CAS 2017年第8期1443-1449,共7页
AIM To explore the association between Helicobacter pylori(H. pylori) infection status, intestinal metaplasia(IM), and colorectal adenomas.METHODS We retrospectively reviewed 1641 individuals aged ≥ 40 years who unde... AIM To explore the association between Helicobacter pylori(H. pylori) infection status, intestinal metaplasia(IM), and colorectal adenomas.METHODS We retrospectively reviewed 1641 individuals aged ≥ 40 years who underwent physical examination, laboratory testing, 13C-urea breath testing, gastroscopy, colonoscopy, and an interview to ascertain baseline characteristics and general state of health. Histopathological results were obtained by gastric and colorectal biopsies.RESULTS The prevalence of H. pylori infection and adenomas was 51.5%(845/1641) and 18.1%(297/1641), respectively. H. pylori infection was significantly correlated with an increased risk of colorectal adenomas(crude OR = 1.535, 95%CI: 1.044-1.753, P = 0.022; adjusted OR = 1.359, 95%CI: 1.035-1.785, P = 0.028). Individuals with IM had an elevated risk of colorectal adenomas(crude OR = 1.664, 95%CI: 1.216-2.277, P = 0.001; adjusted OR = 1.381, 95%CI: 0.998-1.929, P = 0.059). Stratification based on H. pylori infection stage and IM revealed that IM accompanied by H. pylori infection was significantly associated with an increased risk of adenomas(crude OR = 2.109, 95%CI: 1.383-3.216, P= 0.001; adjusted OR = 1.765, 95%CI: 1.130-2.757, P = 0.012).CONCLUSION H. pylori-related IM is associated with a high risk of colorectal adenomas in Chinese individuals. 展开更多
关键词 Helicobacter pylori 中国人口 Colorectal 肠的组织变形 长期的胃炎
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Capability of cation exchange technology to remove proven N-nitrosodimethylamine precursors
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作者 Shixiang Li Xulan Zhang +5 位作者 Er Bei Huihui Yue Pengfei Lin Jun Wang Xiaojian Zhang Chao Chen 《环境科学学报:英文版》 SCIE EI CAS CSCD 2017年第8期331-339,共9页
N-nitrosodimethylamine (NDMA ) 先锋由一个断然控告的 dimethylamine 组和非极的一半组成,它鼓舞了我们开发一种指向的阳离子交换技术移开 NDMA 先锋。在这研究,我们测试了二位代表性的 NDMA 先锋, dimethylamine (直接存储器存取)... N-nitrosodimethylamine (NDMA ) 先锋由一个断然控告的 dimethylamine 组和非极的一半组成,它鼓舞了我们开发一种指向的阳离子交换技术移开 NDMA 先锋。在这研究,我们测试了二位代表性的 NDMA 先锋, dimethylamine (直接存储器存取) 和 ranitidine (RNTD ) 的移动,由强壮的酸的阳离子交换树脂。结果证明 pH 极大地影响了交换效率,与高移动(直接存储器存取 ?>?78% 并且 RNTD ?>?94%) 在 pH 观察了 ?<?pk<sub ></sub>-1 当到先锋的交换能力的臼齿的比率是 4 时。交换顺序如下被获得:Ca <sup>2?+</sup>?>?Mg<sup>2?+</sup>?>?RNTD<sup>+</sup>?>?K<sup>+</sup>?>?DMA<sup>+</sup>?>?NH<sub>4</sub><sup>+</sup>?>?Na<sup>+</sup> 。到 Na <sup>+</sup> 的直接存储器存取 <sup>+</sup> 的分区系数是 1.41 ? 敢椠 ?楤晳癡 吗? 展开更多
关键词 二甲基亚硝胺 离子交换技术 前体 强酸性阳离子交换树脂 去除能力 离子交换动力学 证明 离子交换过程
Electrical analysis of inter-growth structured Bi4Ti3O12-Na0.5Bi4.5Ti4O15 ceramics
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作者 江向平 江亚林 +3 位作者 江兴安 陈超 涂娜 陈云婧 《中国物理B:英文版》 SCIE EI CAS CSCD 2017年第7期386-392,共7页
共生交互生长铋组织层的铁电体(BLSF ) ,双性人 <sub>4</sub > Ti <sub>3</sub > O <sub>12</sub>-Na<sub>0.5</sub > 双性人 <sub>4.5</sub > Ti <sub>4</sub ... 共生交互生长铋组织层的铁电体(BLSF ) ,双性人 <sub>4</sub > Ti <sub>3</sub > O <sub>12</sub>-Na<sub>0.5</sub > 双性人 <sub>4.5</sub > Ti <sub>4</sub > O <sub>15</sub>(BIT-NBT ) ,成功地被综合使用传统固态反应方法。X 光检查衍射(XRD ) Rietveld 精炼用 GSAS 软件被进行。好同意和低剩余被获得。XRD 衍射山峰能很好被索引进 I2cm 空间组。共生交互生长结构进一步在高分辨率的 TEM 图象被观察。电介质和阻抗性质被测量并且系统地分析了。在温度范围 763-923 K (下面,二倍地电离了氧空缺(OV ) 是局部性的,短期的跳跃与 0.79-1.01 eV 的一个激活精力导致松驰过程。上面,二倍地控告的 OV 被去除并且成为免费的,它贡献远程的 dc 传导。在松驰种类的减小产生更高的松驰激活精力 ~ 1.6 eV。 展开更多
关键词 生长结构 陶瓷 铋层状结构 固相反应法 SAS软件 X射线衍射 电镜图像 阻抗特性
长挡板结构型式对竖缝式鱼道鱼池流速影响研究 预览
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作者 毛熹 张杰豪 +5 位作者 沈敬雄 陈胥良 段晨阳 陈超 余吉奎 梁心蓝 《土木工程》 2017年第3期267-271,共5页
大坝和堤堰等水工建筑物的修建截断了河流,使河流中鱼类的栖息地及洄游路线受到极为严重的干扰。为了解决鱼类的洄游问题,修建鱼道是广泛采用的工程措施,其中,以竖缝式鱼道的数量居多。本文从竖缝式鱼道的长挡板细部构造入手,通过模型... 大坝和堤堰等水工建筑物的修建截断了河流,使河流中鱼类的栖息地及洄游路线受到极为严重的干扰。为了解决鱼类的洄游问题,修建鱼道是广泛采用的工程措施,其中,以竖缝式鱼道的数量居多。本文从竖缝式鱼道的长挡板细部构造入手,通过模型实验的手段,对比分析了三种方案对竖缝式鱼道鱼池流速的影响。通过研究,推荐竖缝式鱼道的长挡板结构型式为“直钩”型。 展开更多
关键词 竖缝式鱼道 模型实验 长挡板 流速
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携带人肝细胞生长因子第一结构域基因溶瘤腺病毒的构建及其对胃癌细胞的杀伤作用 被引量:1
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作者 巢晨 马贵亮 +1 位作者 任红 毛伟征 《中华实验外科杂志》 CSCD 北大核心 2017年第6期973-975,共3页
目的构建携带具有抗肿瘤细胞和抗血管生成作用的人肝细胞生长因子第一结构域(HGFK1)基因的肿瘤特异性启动子调控的溶瘤腺病毒,研究其对胃癌细胞选择性杀伤作用。方法以人端粒酶反转录酶启动子(hTERT)和缺氧调控元件序列(HRE)分... 目的构建携带具有抗肿瘤细胞和抗血管生成作用的人肝细胞生长因子第一结构域(HGFK1)基因的肿瘤特异性启动子调控的溶瘤腺病毒,研究其对胃癌细胞选择性杀伤作用。方法以人端粒酶反转录酶启动子(hTERT)和缺氧调控元件序列(HRE)分别调控溶瘤腺病毒复制必要的E1a和E1b基因,基因组插入HGFK1基因,构建HGFK1溶瘤腺病毒(TH—Ad—HGFK1-EGFP)和无HGFK1溶瘤腺病毒(TH—Ad—EGFP),空斑计数法滴定病毒浓度;病毒分为3组:实验A组(TH-Ad—HGFK1-EGFP)、实验B组(TH-Ad—EGFP)和对照C组(Ad-EGFP),分别感染胃癌细胞SGC7901和正常人成纤维细胞(HF);半数细胞培养物感染量法(TCID50)检测病毒扩增倍数;噻唑蓝(MTT)法检测病毒杀伤抑制作用;双重荧光染色检测病毒促凋亡作用。结果溶瘤腺病毒TH—Ad—HGFK1-EGFP、TH-Ad—EGFP经测序及聚合酶链反应(PCR)鉴定确认构建成功,滴度都为2×10^10pfu/ml;病毒扩增结果显示:A、B组病毒在SGC7901细胞中的扩增倍数分别为1.47×10^4、1.60×10^4倍,远大于对照C组病毒,在HF细胞中为110倍和124倍,远小于对照C组病毒;MTF结果显示:当感染复数(MOI)=100时,A组病毒对SGC7901细胞72、96h后的抑制率为(71.34±8.27)%、(74.56±1.78)%,B组为(30.58±3.83)%、(31.84±6.62)%,C组为(23.40±2.29)%、(21.18-4-2.32)%。A组与B组两时间点分别比较差异有统计学意义(P=0.002、P=0.003),A组与C组分别比较差异有统计学意义(P=0.003、P=0.000)。A、B组病毒对HF细胞在96h后的抑制率为(18.94±0.88)%、(22.84±3.34)%,C组为(53.25±3.50)%,A、B两组与C组分别比较差异有统计学意义(P=0.003、P=0.001);凋亡结果显示:A组SGC7901细胞的凋亡率为(18.66±4.04)%,远高于其余各组。结论溶瘤腺病� 展开更多
关键词 胃癌 人肝细胞生长因子第一结构域 溶瘤腺病毒 SGC7901
Constitutive Overexpression of Myo-inositol-1-Phosphate Synthase Gene (GsMIPS2) from Glycine soja Confers Enhanced Salt Tolerance at Various Growth Stages in Arabidopsis 预览
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作者 Zaib-un-Nisa Chen Chen +5 位作者 Yang Yu Chao Chen ALi Inayat Mallano Duan Xiang-bo Sun Xiao-li Zhu Yan-ming 《东北农业大学学报:英文版》 CAS 2016年第2期28-44,共17页
The enzyme myo-inositol-1-phosphate synthase(MIPS EC 5.5.1.4) catalyzes the first step of myo-inositol biosynthesis, a product that plays crucial roles in plants as an osmoprotectant, transduction molecule, cell wall ... The enzyme myo-inositol-1-phosphate synthase(MIPS EC 5.5.1.4) catalyzes the first step of myo-inositol biosynthesis, a product that plays crucial roles in plants as an osmoprotectant, transduction molecule, cell wall constituent and production of stress related molecule. Previous reports highlighted an important role of MIPS family genes in abiotic stresses particularly under salt stress tolerance in several plant species; however, little is known about the cellular and physiological functions of MIPS2 genes under abiotic conditions. In this study, a novel salt stress responsive gene designated Gs MIPS2 from wild soybean Glycine soja 07256 was functionally characterized contained an open reading frame(ORF) of 1 533 bp coding a peptide sequence of 510 amino acids along with mass of 56 445 ku. Multiple sequence alignment analysis revealed its 92%-99% similarity with other MIPS family members in legume proteins. Quantitative real-time PCR results demonstrated that Gs MIPS2 was induced by salt stress and expressed in roots of soybean. The positive function of Gs MIPS2 under salt response at different growth stages of transgenic Arabidopsis was also elucidated. The results showed that Gs MIPS2 transgenic lines displayed increased tolerance as compared to WT and atmips2 mutant lines under salt stress. Furthermore, the expression levels of some salt stress responsive marker genes, including KIN1, RD29 A, RD29 B, P5 Cs and COR47 were significantly up-regulated in Gs MIPS2 overexpression lines than wild type and atmips2 mutant. Collectively, these results suggested that Gs MIPS2 gene was a positive regulator of plant tolerance to salt stress. This was the first report to demonstrate that overexpression of Gs MIPS2 gene from wild soybean improved salt tolerance in transgenic Arabidopsis. 展开更多
关键词 Glycine soja Arabidopsis thaliana MIPS salt stress functional analysis
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Tolvaptan regulates aquaporin-2 and fecal water in cirrhotic rats with ascites 预览 被引量:1
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作者 Chao Chen Ren-Pin Chen +3 位作者 Hai-Hua Lin Wen-You Zhang Xie-Lin Huang Zhi-Ming Huang 《世界胃肠病学杂志:英文版》 SCIE CAS 2016年第12期3363-3371,共9页
AIM: To investigate the role of tolvaptan in regulating aquaporin(AQP)-2 expression and fecal water content in cirrhotic rats with ascites.METHODS: Cirrhosis with ascites was induced in rats by repetitive dorsal injec... AIM: To investigate the role of tolvaptan in regulating aquaporin(AQP)-2 expression and fecal water content in cirrhotic rats with ascites.METHODS: Cirrhosis with ascites was induced in rats by repetitive dorsal injection of CCl4 for 14 wk. In total, 84 cirrhotic rats with ascites divided into three groups(vehicle, 3 mg/kg and 5 mg/kg tolvaptan), and then further divided into five subgroups(days 1, 2, 3, 4, and 5). Blood samples were obtained to measure vasopressin and sodium concentrations. Rats were killed and colonic mucosa was scraped for analysis of protein expression and AQP-2 transcriptional level. The whole layer was fixed for hematoxylin&eosin(HE) staining and feces were collected for determination of fecal water content. CONCLUSION: Compared with vehicle, vasopressin decreased significantly in the tolvaptan groups from day 2 to a similar level in each treatment group. AQP-2 showed significant upregulation in cirrhotic rats with ascites compared with an untreated control group(100% ± 22.9% vs 22.2% ± 10.23%, P < 0.01). After administration of tolvaptan, AQP-2 expression began to decrease significantly from day 2 in each treatment group, but no significant difference was finally found between the treatment groups. Fecal water content inthe distal colon was increased by 5 mg/kg tolvaptan on day 1(66.8% ± 9.3% vs 41.4% ± 6.3%, in the vehicle group, P < 0.05). Fecal water content returned to baseline at day 4 at the latest in both treatment groups, and did not correspond to the change in AQP-2 expression. HE staining of the colonic mucosa showed no mucosal damage related to tolvaptan.CONCLUSION: Upregulation of AQP-2 in the distal colon is found in cirrhotic rats with ascites. Tolvaptan inhibits its expression and may decrease water reabsorption and induce diarrhea. 展开更多
关键词 TOLVAPTAN AQUAPORIN-2 CIRRHOSIS ASCITES
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