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自体骨髓干细胞原位移植治疗急性心肌梗死的临床研究 被引量:74
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作者 陈运贤 欧瑞明 +5 位作者 钟雪云 徐新 赵洪云 管慧红 陆英 韩忠朝 《中国病理生理杂志》 CAS CSCD 北大核心 2003年第4期452-454,T002,共4页
目的 :用粒细胞集落刺激因子 (G -CSF)动员自体骨髓干细胞进入心肌梗死部位原位移植以修复梗死心肌组织 ,探讨其对急性心肌梗死患者心肌梗死面积及心功能的影响。方法 :2 5例初次急性心肌梗死患者在入院后随机分为干细胞原位移植组 (n =... 目的 :用粒细胞集落刺激因子 (G -CSF)动员自体骨髓干细胞进入心肌梗死部位原位移植以修复梗死心肌组织 ,探讨其对急性心肌梗死患者心肌梗死面积及心功能的影响。方法 :2 5例初次急性心肌梗死患者在入院后随机分为干细胞原位移植组 (n =12 )和对照组 (n =13)。干细胞原位移植组于入院后在常规治疗基础上加用G -CSF动员自体骨髓干细胞进行心肌梗死原位移植 ;对照组按急性心肌梗死常规方法治疗。于入院第 ( 1、2 8d)描记常规 12导联心电图 ,采用Wagner的QRS波群记分法评价心功能 ,于入院 ( 7、2 8d)行核素心肌灌注断层显像 ,测量心肌梗死面积。结果 :G -CSF治疗 4周 ,干细胞原位移植组QRS记分值明显降低 ,显著低于对照组 (P <0 0 5 ) ;心肌梗死面积由 36 0 %± 8 3%下降至 18 0 %± 5 8%,显著小于对照组 (P <0 0 5 )。结论 :用G -CSF动员自体骨髓干细胞来修复坏死心肌组织的“干细胞原位移植”疗法 ,能减小心肌梗死的范围 ,改善心功能。 展开更多
关键词 自体骨髓干细胞 原位移植 治疗 急性心肌梗死 临床研究 心功能 心肌再生 粒细胞集落刺激因子
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Effects of hepatitis B virus infection on human sperm chromosomes 被引量:52
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作者 Jian-MinHuang Tian-HuaHuang +6 位作者 Huan-YingQiu Xiao-WuFang Tian-GangZhuang Hong-XiLiu Yong-HuaWang, Li-ZhiDeng Jie-WenQiu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第4期736-740,共5页
AIM: To evaluate the level of sperm chromosome aberrations in male patients with hepatitis B, and to directly detect whether there are HBV DNA integrations in sperm chromosomes of hepatitis B patients.METHODS: Sperm c... AIM: To evaluate the level of sperm chromosome aberrations in male patients with hepatitis B, and to directly detect whether there are HBV DNA integrations in sperm chromosomes of hepatitis B patients.METHODS: Sperm chromosomes of 14 tested subjects (5healthy controls, 9 patients with HBV infection, including 1with acute hepatitis B, 2 with chronic active hepatitis B, 4with chronic persistent hepatitis B, 2 chronic HBsAg carriers with no clinical symptoms) were prepared using interspecific in vitro fertilization between zona-free golden hamster ova and human spermatozoa, and the frequencies of aberration spermatozoa were compared between subjects of HBV infection and controls. Fluorescence in situ hybridization (FISH) to sperm chromosome spreads was carried out with biotin-labeled full length HBV DNA probe to detect the specific HBV DNA sequences in the sperm chromosomes.RESULTS: The total frequency of sperm chromosome aberrations in HBV infection group (14.8%, 33/223) was significantly higher than that in the control group (4.3%,5/116). Moreover, the sperm chromosomes in HBV infection patients commonly presented stickiness, clumping, failure to staining, etc, which would affect the analysis of sperm chromosomes. Specific fluorescent signal spots for HBV DNA were seen in sperm chromosomes of one patient with chronic persistent hepatitis. In 9 (9/42) sperm chromosome complements containing fluorescent signal spots, one presented 5 obvious FISH spots, others presented 2 to 4signals. There was significant difference of fluorescence intensity among the signal spots. The distribution of signal sites among chromosomes was random.CONCLUSION: HBV infection can bring about mutagenic effects on sperm chromosomes. Integrations of viral DNA into sperm chromosomes which are multisites and nonspecific, can further increase the instability of sperm chromosomes. This study suggested that HBV infection can create extensively hereditary effects by alteration genetic constituent and/or induction chromosome aberrations, as well as t 展开更多
关键词 ADULT Chromosomes Human DNA Viral Hepatitis B Antigens Hepatitis B Surface Antigens Hepatitis B Chronic Humans In situ Hybridization Fluorescence KARYOTYPING Male Reference Values Research Support Non-U.S. Gov't SEMEN SPERMATOZOA
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Studies on the integration of hepatitis B virus DNA sequence in human sperm chromosomes 被引量:49
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作者 Jian-Min HUANG Tian-Hua HUANG +3 位作者 Huan-Ying QIU Xiao-Wu FANG Tian-Gang ZHUANG Jie-Wen QIU 《Asian Journal of Andrology》 SCIE CAS CSCD 2002年第3期209-212,共4页
Aim: To study the integration of hepatitis B virus (HBV) DNA into sperm chromosomes in hepatitis B patients and the features of its integration. Methods: Sperm chromosomes of 14 subjects (5 healthy controls and 9 HB p... Aim: To study the integration of hepatitis B virus (HBV) DNA into sperm chromosomes in hepatitis B patients and the features of its integration. Methods: Sperm chromosomes of 14 subjects (5 healthy controls and 9 HB patients, including 1 acute hepatitis B, 2 chronic active hepatitis B, 4 chronic persistent hepatitis B, 2 HBsAg chronic carriers with no clinical symptoms) were prepared using interspecific in vitro fertilization between zona-free hamster oocytes and human spermatozoa. Fluorescence in situ hybridization (FISH) to sperm chromosome spreads was carried out with biotin-labeled full length HBV DNA probe to detect the specific HBV DNA sequences in the sperm chromosomes. Results: Specific fluorescent signal spots for HBV DNA were seen in sperm chromosomes of one patient with chronic persistent hepatitis B. In 9(9/42) sperm chromosome complements containing fluorescent signal spots, one presented 5 obvious FISH spots and the others 2 to 4 signals. The fluorescence intensity showed significant difference among the signal spots. The distribution of signal sites among chromosomes seems to be random. Conclusion: HBV could integrate into human sperm chromosomes. Results suggest that the possibility of vertical transmission of HBV via the germ line to the next generation is present. 展开更多
关键词 hepatitis B virus SPERMATOZOA human chromosomes fluorescence in situ hybridization virus integration vertical disease transmission
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Methodologic research on TIMP-1,TIMP-2 detection as a new diagnostic index for hepatic fibrosis and its significance 被引量:51
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作者 Oing-He Nie Yong-Oian Cheng Yu-Mei Xie Yong-Xing Zhou Bai-Xian Guang Yi-Zhan Cao,The Centre of Diagnosis and Treatment for Infectious Disease of Chinese PLA,Tangdu Hospital,Fourth Military Medical University,Xi’an 710038,Shanxi Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期282-287,共6页
AIM: To set up a new method to detect tissue inhibitors of metalloproteinase-1 and -2(TIMP-1 and TIMP-2) in sera of patients with hepatic cirrhosis, and to investigate the expression and location of TIMP-1 and TIMP-2 ... AIM: To set up a new method to detect tissue inhibitors of metalloproteinase-1 and -2(TIMP-1 and TIMP-2) in sera of patients with hepatic cirrhosis, and to investigate the expression and location of TIMP-1 and TIMP-2 in liver tissue of patients with hepatic cirrhosis, and the correlation between TIMPs in liver and those in sera so as to discuss whether TIMPs can be used as a diagnosis index of hepatic fibrosis. METHODS: The monoclonal antibodies (McAbs) of TIMP-1 and TIMP-2 were used to sensitize erythrocytes, and solid-phase absorption to sensitized erythrocytes (SPASE) was used to detect TIMP-1 and TIMP-2 in the sera of patients with hepatic cirrhosis. Meanwhile, with the method of in situ hybridization and immunohistochemistry, we studied the mRNA expression and antigen location of TIMP-1 and TIMP-2 in the livers of 40 hepatic cirrhosis patients with pathologic diagnosis. RESULTS: With SPASE, they were 16.4% higher in the acute hepatitis group, 33.3% higher in the chronic hepatitis group, and the positive rates were 73.6% and 61.2% respectively in sera of hepatic cirrhosis patients, which were remarkably higher than those in chronic hepatitis and acute hepatitis group (P【0.001). In 40 samples of hepatic cirrhosis tissues, all of them showed positive expression of TIMP-1 and TIMP-2 mRNA detected with immunohistochemistry or in situ hybridization (positive rate was 100%). Expression of TIMPs in different degrees could be found in liver tissue with cirrhosis. TIMPs were located in cytoplasm of liver cells of patients with hepatic cirrhosis. There was a significant correlation between serum TIMPs level and liver TIMPs level. CONCLUSION: SPASE is a useful method to detect the TIMP-1 and TIMP-2 in sera of patients with hepatic cirrhosis, and TIMP-1 and TIMP-2 can be considered as a useful diagnostic index of hepatic fibrosis, especially TIMP-1. 展开更多
关键词 Antibodies Monoclonal Erythrocytes Humans IMMUNOASSAY In situ Hybridization Liver Liver Cirrhosis Protease Inhibitors Research Support Non-U.S. Gov't Tissue Inhibitor of Metalloproteinase-1 Tissue Inhibitor of Metalloproteinase-2
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Caspase-3 and survivin expression in pediatric neuroblastoma and their roles in apoptosis 被引量:39
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作者 王家祥 郑树 《Chinese Medical Journal》 SCIE CAS CSCD 2004年第12期1821-1824,共4页
Background Neuroblastoma, one of the common tumors in children, possesses the feature of natural regression that might be related to apoptosis caspase 3 and survivin are believed to respectively induce and inhibit apo... Background Neuroblastoma, one of the common tumors in children, possesses the feature of natural regression that might be related to apoptosis caspase 3 and survivin are believed to respectively induce and inhibit apoptosis. We investigated the expression of caspase 3 and survivin in pediatric neuroblastoma and the role that these genes played in apoptosis Methods The expression of caspase 3 and survivin in pediatric neuroblastoma tissue samples was detected using in situ hybridization, ter mintuesal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL), and immunohistochemical staining The role that these genes played in apoptosis was then evaluated Results A converse correlation was observed between the expression of survivin and caspase 3 When survivin was expressed at high levels in neuroblastoma samples, caspase 3 expression was downregulated, and the apoptotic index decreased simultaneously Conclusion There is a converse correlation between the expression of caspase 3 and the expression of survivin in neuroblastoma cells, indicating that caspase-3 might induce apoptosis, and survivin may inhibit this process 展开更多
关键词 CASPASE-3 SURVIVIN NEUROBLASTOMA TUNEL APOPTOSIS in situ hybridization
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冰厚变化的现场监测现状和研究进展 被引量:44
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作者 李志军 韩明 +2 位作者 秦建敏 郗玉珠 卢鹏 《水科学进展》 EI CAS CSCD 北大核心 2005年第5期753-757,共5页
根据湖河海冰、冰川冰资源与环境中的自然科学问题及冬季冰区结构物安全运行管理中的工程科学问题对冰厚度时空变化资料的要求,总结了现行冰厚度变化过程监测方法的适用范围和优缺点。强调目前所获数据因连续监测时间短,精度达不到毫米... 根据湖河海冰、冰川冰资源与环境中的自然科学问题及冬季冰区结构物安全运行管理中的工程科学问题对冰厚度时空变化资料的要求,总结了现行冰厚度变化过程监测方法的适用范围和优缺点。强调目前所获数据因连续监测时间短,精度达不到毫米级,对建立和检验冰物质平衡同环境条件的预报模式提供不了强有力的支持。为此发展了新的冰厚度变化过程监测方法,它们包括直接探测冰层界面位置的接触式和利用气、冰、水电导率差异的标尺式高精度冰、雪层生消过程自动监测设备。详细描述了它们的工作原理、研究进展、适用范围和在极地海冰以及国内河冰实践获得的初步结果。 展开更多
关键词 厚度测量 冻结 消融 现场 监测
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Dynamic changes of typeⅠ,Ⅲand N collagen synthesis and distribution of collagen-producing cells in carbon tetrachloride-induced rat liver fibrosis 被引量:47
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作者 DU Wei-Dong ZHANG Yue-E ZHAl Wei-Rong and ZHOU Xiao-Mei(Department of Pathology, Shanghai Medical University, Shanghai200032, China)(National Laboratory for Oncogenes and Related Genes, ShanghaiCencer Institute)See invited commentary on page 388 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第5期397-403,共7页
AIM To find out the relationship between the gene transcription of different types ofprocollagen and the deposition of the relevant collagens in the liver tissue and to confirm the types of collagen producing cells in... AIM To find out the relationship between the gene transcription of different types ofprocollagen and the deposition of the relevant collagens in the liver tissue and to confirm the types of collagen producing cells in liverfibrogenesis.METHODS Dynamic changes of the expression of α1(Ⅰ ), α1 (Ⅲ ) and α1 (Ⅳ) procollagen mRNAand relevant collagens and the distribution ofcollagen producing cells during liver fibrogenesis of rat induced by CCl4 (20 weeks)were investigated with Northern blot analysis,in situ hybridization and immunohistochemicaltechniques.RESULTS The increased expression of α1 (Ⅲ)procollagen mRNA by Northern blot analysis was the most predominant one among the threemRNAs during fibrogenesis. However, theenhanced expression of al (Ⅳ) procollagenmRNA occurred very early while the expressionof α1 (Ⅰ) mRNA was not enhanced much until themiddle stage of the exPeriment. D6smin (Dm)positive hepatic stellate cells (HSCs) and fewmyofibroblasts (MFs) in and around the necrotic areas expressed α1 (Ⅰ), α1 (Ⅲ) and α1 (Ⅳ)procollagen mRNA signals detected by in situhybridization at the early stage of theexperiment. All the three procollagen mRNAsignals thereafter mainly localized in fibroblasts (Fbs) and MFs in fibrotic septa during the middle and late stages of fibrosis, which distributedparallel to the corresponding collagens detected by immunohistochemical study. ln addition, the endothelial cells of sinusoids and the small blood vessels within the septa also showed α1(Ⅳ) procollagen mRNA and type Ⅳ collagen expressionCONCLUSION It is considered that "HSC-MF-Fb" effect cell system is the major cellularsource of collagen production in liver fibrosis, in which HSCs are collagen producing precursor cells in the early liver fibrogenesis, thereafter the synthesis of type Ⅰ, Ⅲ and Ⅳ collagens (Col Ⅰ, Col Ⅲ and Col Ⅳ) mainly derives fromMFs and Fbs, which play a very important role in the progress of liver fibrosis. The endothelialcells along sinusoids, as another source of Col 展开更多
关键词 PROCOLLAGEN mRNA immunohistochemistry Northern blot analysis in situ hybridization liver FIBROSIS
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原位内生Al/Mg_2Si/Si复合材料铸态组织研究 被引量:33
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作者 张健 王玉庆 +1 位作者 杨滨 周本濂 《复合材料学报》 EI CAS CSCD 北大核心 1999年第4期30-34,共5页
利用普通重力铸造方法, 制备了原位内生Al/Mg2Si/Si复合材料。研究了体系中加入过量Si后的显微组织, 并利用Al-Mg2Si-Si三元相图进行分析。结果表明, 过量Si使复合材料中的大长径比的Al+ Mg2Si二... 利用普通重力铸造方法, 制备了原位内生Al/Mg2Si/Si复合材料。研究了体系中加入过量Si后的显微组织, 并利用Al-Mg2Si-Si三元相图进行分析。结果表明, 过量Si使复合材料中的大长径比的Al+ Mg2Si二元共晶向小长径比的Al+ Mg2Si+ Si三元共晶转化, 并使α-Al以球状晶粒析出, 从而改善了显微组织, 显著提高了复合材料的室温拉伸性能。 展开更多
关键词 原位内生 复合材料 显微组织 铸态 铝/硅化镁
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高分辨透射X射线三维成像在材料科学中的应用 被引量:44
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作者 王绍钢 王苏程 张磊 《金属学报》 SCIE EI CAS CSCD 北大核心 2013年第8期897-910,共14页
随着X射线光源、光学器件及图像分析技术的不断发展,微米甚至数十纳米空间分辨X射线三维数字化成像成为可能.在此基础上,提供了高分辨无损探测材料内部结构的技术和方法,预计高分辨X射线三维成像新技术将会进一步促进材料科学技术的发展... 随着X射线光源、光学器件及图像分析技术的不断发展,微米甚至数十纳米空间分辨X射线三维数字化成像成为可能.在此基础上,提供了高分辨无损探测材料内部结构的技术和方法,预计高分辨X射线三维成像新技术将会进一步促进材料科学技术的发展.本文将简述X射线三维成像的产生背景和发展过程,介绍吸收衬度成像、相位衬度成像和全息成像的原理与特点,着重分析高分辨透射X射线三维成像在材料孔洞、裂纹与腐蚀、复合材料以及原位测试等方向的应用及其特点,比较同步辐射与实验室X射线高分辨透射三维成像技术的不同,以探讨高分辨透射X射线三维成像在材料科学研究中进一步应用的可能性. 展开更多
关键词 X射线 三维成像 材料科学 金属 复合材料 原位
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Opportunities and Challenges in Deep Mining: A Brief Review 被引量:40
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作者 Pathegama G. Ranjith Jian Zhao +3 位作者 Minghe Ju Radhika V. S. De Silva Tharaka D. Rathnaweera Adheesha K. M. S. Bandara 《Engineering》 SCIE EI 2017年第4期546-551,共6页
Mineral consumption is increasing rapidly as more consumers enter the market for minerals and as the global standard of living increases. As a result, underground mining continues to progress to deeper levels in order... Mineral consumption is increasing rapidly as more consumers enter the market for minerals and as the global standard of living increases. As a result, underground mining continues to progress to deeper levels in order to tackle the mineral supply crisis in the 21 st century. However, deep mining occurs in a very technical and challenging environment, in which significant innovative solutions and best practice are required and additional safety standards must be implemented in order to overcome the challenges and reap huge eco- nomic gains. These challenges include the catastrophic events that are often met in deep mining engineering: rockbursts, gas outbursts, high in situ and redistributed stresses, large deformation, squeezing and creeping rocks, and high temperature. This review paper presents the current global status of deep mining and high-lights some of the newest technological achievements and opportunities associated with rock mechanics and geotechnical engineering in deep mining. Of the various technical achievements, unmanned workingfaces and unmanned mines based on fully automated mining and mineral extraction processes have become important fields in the 21 st century. 展开更多
关键词 Deep mining Rock mechanics RockburstIn situ stresses Mining automation
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不同施肥模式下夏玉米田间土壤氨挥发规律 被引量:38
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作者 李宗新 王庆成 +4 位作者 刘开昌 董树亭 王空军 张吉旺 刘春晓 《生态学报》 CAS CSCD 北大核心 2009年第1期307-314,共8页
利用通气法田间原位试验,研究了不同施肥模式对夏玉米田间土壤氨挥发的影响。结果表明:单施化肥与秸秆还田配施化肥处理的田间氨挥发速率日变化与白天田间土壤表层温度(简称地温)变化表现基本一致,呈现由低到高的"单峰"趋势。夏玉... 利用通气法田间原位试验,研究了不同施肥模式对夏玉米田间土壤氨挥发的影响。结果表明:单施化肥与秸秆还田配施化肥处理的田间氨挥发速率日变化与白天田间土壤表层温度(简称地温)变化表现基本一致,呈现由低到高的"单峰"趋势。夏玉米田间氨挥发损失的高峰期主要发生在白天11:00-13:00。但持续时间较短,单施化肥与秸秆还田配施化肥处理均在氮肥施入当天田间氨挥发速率达最高值,此后迅速降低,氨挥发损失主要集中于前7d,累计氨挥发量占总量的88.57%-96.72%。与单施化肥相比,秸秆还田配施化肥可显著减少氨挥发损失4.06-8.25 k.ghm^-2,氨挥发损失率降低0.37%-1.17%。夏玉米大喇叭口期后对氮素需求较多,较高的田间土壤持水量均可以削弱氨挥发损失。确定适宜的秸秆与氮肥配比量,适量增加大喇叭口期的氮肥追施量配合及时浇水,是提高氮肥利用效率的有效途径之一。 展开更多
关键词 夏玉米 氮肥 氨挥发 施肥模式
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硅对Mg_2Si/ZM5复合材料组织和性能的影响 被引量:23
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作者 王连登 傅高升 +1 位作者 陈晓 钱匡武 《特种铸造及有色合金》 CAS CSCD 北大核心 2003年第2期7-10,共4页
在真空感应炉中氩气保护下制备材料 ,采用OM ,SEM ,EDAX和XRD及拉伸试验 ,研究分析了硅对原位反应自生Mg2 Si/ZM5复合材料铸态显微组织和性能的影响规律。结果表明 ,反应添加物Si在ZM5合金中形成了高熔点、高硬度的Mg2 Si强化相 ,明显... 在真空感应炉中氩气保护下制备材料 ,采用OM ,SEM ,EDAX和XRD及拉伸试验 ,研究分析了硅对原位反应自生Mg2 Si/ZM5复合材料铸态显微组织和性能的影响规律。结果表明 ,反应添加物Si在ZM5合金中形成了高熔点、高硬度的Mg2 Si强化相 ,明显地提高了材料的室温与高温强度 ,如Si的质量分数为 1.5 %时 ,室温抗拉强度与屈服强度提高幅度分别可达 2 0 .1%和 61.5 % ,Si的质量分数为 1.0 %时 ,高温抗拉强度与屈服强度提高幅度分别可达 14 .9%和 2 5 .7% ;Mg2 Si相的形貌随着硅含量的不同而变化 ,如Si的质量分数为 0 .5 %时 ,主要生成细小短棒状或片状共晶Mg2 Si相 ,Si的质量分数大于1%时 ,则出现了粗大块状或汉字状初生Mg2 Si相和片状或短棒状的共晶Mg2 Si相 ;由于所生成的Mg2 Si相本身是一种脆性相 ,使得该材料呈现出解理断裂 ,降低了材料的塑性。 展开更多
关键词 ZM5基复合材料 原位反应 MG2SI
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燃气热脱附技术修复有机污染场地研究与应用进展 被引量:38
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作者 李书鹏 焦文涛 +5 位作者 李鸿炫 宋少宇 籍龙杰 刘鹏 詹明秀 王进卿 《环境工程学报》 CAS CSCD 北大核心 2019年第9期2037-2048,共12页
原位燃气热脱附是目前修复有机污染土壤最具潜力的技术之一。在查阅文献的基础上,结合国内外实际案例,系统梳理了有机污染土壤原位燃气热脱附修复技术的原理、适用范围、优缺点以及工艺施工流程,对国内外燃气热脱附技术的研究现状和工... 原位燃气热脱附是目前修复有机污染土壤最具潜力的技术之一。在查阅文献的基础上,结合国内外实际案例,系统梳理了有机污染土壤原位燃气热脱附修复技术的原理、适用范围、优缺点以及工艺施工流程,对国内外燃气热脱附技术的研究现状和工程应用情况进行了对比分析,并对该技术的发展趋势和应用前景进行了展望,以期为我国有机污染土壤原位热修复技术的推广和应用提供参考。 展开更多
关键词 有机污染场地 土壤修复 原位 燃气热脱附
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重金属污染土壤的电动原位修复技术研究 被引量:34
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作者 王慧 马建伟 +1 位作者 范向宇 罗启仕 《生态环境》 CSCD 北大核心 2007年第1期223-227,共5页
电动力学修复技术作为一种新型的修复技术,由于其处理土壤污染的高效性,近几年来受到了越来越多的关注。综述了电动力学修复技术原理及近几年来其在重金属修复中的最新研究进展,阐述了电动力学修复技术相对于其它修复技术的优势,并指出... 电动力学修复技术作为一种新型的修复技术,由于其处理土壤污染的高效性,近几年来受到了越来越多的关注。综述了电动力学修复技术原理及近几年来其在重金属修复中的最新研究进展,阐述了电动力学修复技术相对于其它修复技术的优势,并指出了电动修复技术中需要克服的技术障碍,探讨了其大规模商业应用的可行性。电动技术能够强化土壤物质的传质过程,能够高效、快速定向迁移土壤中重金属离子达到去除的目的;同时电动技术可以与其它修复技术结合发展出系列组合修复技术,具有广泛的应用前景。从单一电动到复合电动是今后电动力学技术发展的重要方向。目前对污染物质复合电动力学效应下的迁移机理及模型、不同土壤性质(组分、酸碱性等)对于污染物质去除效率及其调控措施的研究仍需进一步深入。 展开更多
关键词 重金属 电动力学 原位 土壤修复
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大岗山水电站地下厂房区初始地应力场Nelder-Mead优化反演研究 被引量:35
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作者 贾善坡 陈卫忠 +1 位作者 谭贤君 吕森鹏 《岩土力学》 EI CAS CSCD 北大核心 2008年第9期2341-2349,共9页
初始地应力是大型地下洞室群设计与施工所要考虑的重要因素之一。结合大岗山水电站工程地质条件以及实测地应力资料,分析了地下厂房区初始地应力的影响因素,建立了基于侧压力系数的三维地应力反演模型,提出Nelder-Mead法与有限元联合反... 初始地应力是大型地下洞室群设计与施工所要考虑的重要因素之一。结合大岗山水电站工程地质条件以及实测地应力资料,分析了地下厂房区初始地应力的影响因素,建立了基于侧压力系数的三维地应力反演模型,提出Nelder-Mead法与有限元联合反演法,将有限元程序作为一个单独模块嵌入到Nelder-Mead算法程序中,对建立的地质概化模型进行计算,以实测点地应力值与计算应力值建立精确罚函数误差模型,进行优化逼近分析。通过实测点的计算应力值与现场实测值的比较,从而获得地下厂房区初始地应力场较为合理的分布规律,为水电站开挖模拟及长期稳定性分析提供了合理的初始条件。 展开更多
关键词 初始应力场 反演分析 Nelder—Mead算法 有限元
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LA-MC-ICP-MS独居石微区原位U-Pb同位素年龄测定 被引量:38
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作者 崔玉荣 周红英 +2 位作者 耿建珍 李怀坤 李惠民 《地球学报》 EI CAS CSCD 北大核心 2012年第6期865-876,共12页
独居石富含U、Th,同时具有较低的初始普通Pb含量,是U-Pb和Th-Pb同位素定年的理想对象。由于普遍存在于多种岩石中,独居石的U-Th-Pb定年具有广阔的应用前景。本文报道利用193nmArF准分子激光剥蚀系统和NEPUNE多接收器电感耦合等离子体质... 独居石富含U、Th,同时具有较低的初始普通Pb含量,是U-Pb和Th-Pb同位素定年的理想对象。由于普遍存在于多种岩石中,独居石的U-Th-Pb定年具有广阔的应用前景。本文报道利用193nmArF准分子激光剥蚀系统和NEPUNE多接收器电感耦合等离子体质谱仪,对独居石进行微区原位U-Pb同位素年龄测定的新方法。运用这一新方法对独居石样品AL01、BL02和CL03进行微区原位U-Pb同位素年龄测定,获得AL01和BL02号样品的206Pb/238U年龄加权平均值分别为(288.3±1.1)Ma(n=19)和(446.8±2.3)Ma(n=41);CL03号样品的U-Pb等时线年龄为(396.8±8.8)Ma(n=55),取得了令人满意的结果。 展开更多
关键词 独居石 微区原位 LA-MC-ICP-MS U-Pb同位素测年
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Molecular Cytogenetic Characterization of Wheat-Thinopyrum elongatum Addition,Substitution and Translocation Lines with a Novel Source of Resistance to Wheat Fusarium Head Blight 被引量:36
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作者 Shulan Fu Zhenling Lv +4 位作者 Bao Qi Xiang Guo Jun Li Bao Liu Fangpu Han 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2012年第2期103-110,共8页
Thinopyrum elongatum (2n = 2x = 14, EE), a wild relative of wheat, has been suggested as a potentially novel source of resistance to several major wheat diseases including Fusarium Head Blight (FHB). In this study... Thinopyrum elongatum (2n = 2x = 14, EE), a wild relative of wheat, has been suggested as a potentially novel source of resistance to several major wheat diseases including Fusarium Head Blight (FHB). In this study, a series of wheat (cv. Chinese Spring, CS) substitution and ditelosomic lines, including Th. elongatum additions, were assessed for Type II resistance to FHB. Results indicated that the lines containing chromosome 7E of Th. elongatum gave a high level of resistance to FHB, wherein the infection did not spread beyond the inoculated floret. Furthermore, it was determined that the novel resistance gene(s) of 7E was located on the short-ann (7ES) based on sharp difference in FHB resistance between the two 7E ditelosomic lines for each arm. On the other hand, Th. elongatum chromosomes 5E and 6E likely contain gene(s) for susceptibility to FHB because the disease spreads rapidly within the inoculated spikes of these lines. Genomic in situ hybridization (GISH) analysis revealed that the alien chromosomes in the addition and substitution lines were intact, and the lines did not contain discernible genomic aberrations. GISH and multicolor-GISH analyses were further performed on three trans- location lines that also showed high levels of resistance to FHB. Lines TA3499 and TA3695 were shown to contain one pair of wheat-Th. elongatum translocated chromosomes involving fragments of 7D plus a segment of the 7E, while line TA3493 was found to contain one pair of wheat-Th, elongatum translocated chromosomes involving the D- and A-genome chromosomes of wheat. Thus, this study has established that the short-arm of chromosome 7E of Th. elongatum harbors gene(s) highly resistant to the spreading of FHB, and chromatin of 7E introgressed into wheat chromosomes largely retained the resistance, implicating the feasibility of using these lines as novel material for breeding FHB-resistant wheat cultivars. 展开更多
关键词 Thinopyrum elongatum Alien addition lines Substitution lines Fusarium Head Blight resistance (FHB) Genomic in situ hybridization (GISH)
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某退役溶剂厂有机物污染场地燃气热脱附原位修复效果试验 被引量:37
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作者 张学良 李群 +5 位作者 周艳 廖朋辉 辜晓平 占新华 林玉锁 徐建 《环境科学学报》 CAS CSCD 北大核心 2018年第7期2868-2875,共8页
热脱附技术一般用于土壤中有机物的异位修复,然而对于受有机物污染较深土壤的原位修复却鲜有报道.本文以某退役溶剂厂土壤中苯、氯苯和石油类为目标污染物,运用燃气热脱附技术进行原位修复.本文介绍了燃气热脱附技术的工艺设计流程,针... 热脱附技术一般用于土壤中有机物的异位修复,然而对于受有机物污染较深土壤的原位修复却鲜有报道.本文以某退役溶剂厂土壤中苯、氯苯和石油类为目标污染物,运用燃气热脱附技术进行原位修复.本文介绍了燃气热脱附技术的工艺设计流程,针对场地目标污染物进行燃气热脱附的工程化试验,结果显示热脱附处理后土壤中苯、氯苯和石油类最高去除率接近100%.本文还探讨了温度、停留时间、土壤含水率和土壤质地对热脱附效率的影响,发现在温度和停留时间相同情况下,含水率较小、孔隙率较大的粉砂土热脱附效果更好.试验表明,燃气热脱附原位修复技术处理场地挥发性有机污染物效果良好,可以进行大规模的实际运用. 展开更多
关键词 燃气热脱附 原位 有机污染物 土壤修复
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地下水原位生物修复技术 被引量:25
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作者 金朝晖 曹骥赟 戴树桂 《城市环境与城市生态》 CAS CSSCI CSCD 北大核心 2002年第1期10-12,共3页
对地下水原位生物修复技术的概念、实施途径和方案等进行了综述 。
关键词 地下水污染 原位生物修复 环境修复 生态恢复 微生物
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Sulfur-doped g-C3N4/TiO2 S-scheme heterojunction photocatalyst for Congo Red photodegradation 被引量:36
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作者 Juan Wang Guohong Wang +2 位作者 Bei Cheng Jiaguo Yu Jiajie Fan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期56-68,共13页
Constructing step-scheme(S-scheme)heterojunctions has been confirmed as a promising strategy for enhancing the photocatalytic activity of composite materials.In this work,a series of sulfur-doped g-C3N4(SCN)/TiO2 S-sc... Constructing step-scheme(S-scheme)heterojunctions has been confirmed as a promising strategy for enhancing the photocatalytic activity of composite materials.In this work,a series of sulfur-doped g-C3N4(SCN)/TiO2 S-scheme photocatalysts were synthesized using electrospinning and calcination methods.The as-prepared SCN/TiO2 composites showed superior photocatalytic performance than pure TiO2 and SCN in the photocatalytic degradation of Congo Red(CR)aqueous solution.The significant enhancement in photocatalytic activity benefited not only from the 1D well-distributed nanostructure,but also from the S-scheme heterojunction.Furthermore,the XPS analyses and DFT calculations demonstrated that electrons were transferred from SCN to TiO2 across the interface of the SCN/TiO2 composites.The built-in electric field,band edge bending,and Coulomb interaction synergistically facilitated the recombination of relatively useless electrons and holes in hybrid when the interface was irradiated by simulated solar light.Therefore,the remaining electrons and holes with higher reducibility and oxidizability endowed the composite with supreme redox ability.These results were adequately verified by radical trapping experiments,ESR tests,and in situ XPS analyses,suggesting that the electron immigration in the photocatalyst followed the S-scheme heterojunction mechanism.This work can enrich our knowledge of the design and fabrication of novel S-scheme heterojunction photocatalysts and provide a promising strategy for solving environmental pollution in the future. 展开更多
关键词 TiO2 nanofiber Sulfur-doped g-C3N4 Step-scheme heterojunction photocatalysis In situ XPS S-scheme mechanism
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