期刊文献+
共找到47篇文章
< 1 2 3 >
每页显示 20 50 100
人工冻融土地基极限承载力弹塑性数值分析
1
作者 王贵虎 周红 宋学成 《建井技术》 北大核心 2004年第4期23-26,共4页
采用ANSYS程序对人工冻融土地基极限承载力进行弹塑性数值分析。结合试验结果和理论解 ,研究了冻融前后地基极限承载力的变化 ,并探讨了人工冻融土地基破坏机理。
关键词 人工冻土地 极限承载力 弹塑性数值分析 有限元模型
下载PDF
植物基低温融雪剂实验研究 被引量:2
2
作者 栾国颜 杨靓 沈佳兴 《化工时刊》 CAS 2023年第3期18-21,共4页
开发了一种植物基低冰点液态融雪剂的制备方法,并且对其进行了冰点测试、融冰能力、腐蚀性实验研究。结果表明:所制融雪剂冰点可达-28℃,远低于常用的添加丙三醇的植物基融雪剂;其融雪能力达氯化钙融雪剂的90%以上;对铁钉、青草、混凝... 开发了一种植物基低冰点液态融雪剂的制备方法,并且对其进行了冰点测试、融冰能力、腐蚀性实验研究。结果表明:所制融雪剂冰点可达-28℃,远低于常用的添加丙三醇的植物基融雪剂;其融雪能力达氯化钙融雪剂的90%以上;对铁钉、青草、混凝土的腐蚀性对比实验表明融雪剂的腐蚀性均低于氯化钠和氯化钙。冰点、环境危害和融雪化冰能力均符合北京市地方标准《融雪剂DB11/T161—2012》中对低温融雪剂的要求。 展开更多
关键词 植物雪剂 废液 秸秆灰 低冰点
下载PDF
青藏公路下伏多年冻土的融化分析 被引量:13
3
作者 盛煜 刘永智 +2 位作者 张建明 武憼民 章金钊 《冰川冻土》 CSCD 北大核心 2003年第1期43-48,共6页
基于青藏公路沿线高温冻土区和低温冻土区 2组地温观测孔 5a的地温观测资料 ,研究了路基下伏多年冻土的融化状态 ,定量分析了进入路基下多年冻土内的热状况 .结果表明 :路基近地表地温明显高于对应天然地表下的地温 ,路基近地表经历的... 基于青藏公路沿线高温冻土区和低温冻土区 2组地温观测孔 5a的地温观测资料 ,研究了路基下伏多年冻土的融化状态 ,定量分析了进入路基下多年冻土内的热状况 .结果表明 :路基近地表地温明显高于对应天然地表下的地温 ,路基近地表经历的融化期长于对应天然地表 ,高温冻土区路基内已形成贯穿融化夹层 ;进入高温冻土区路基下伏多年冻土内的热收支处于持续不断的吸热状态 ,进入低温多年冻土区的热收支也呈现出吸热明显大于放热的周期性变化 ;高温冻土区接近 0℃的地温及其持续不断的热积累是引起下伏多年冻土不断融化的主要原因 .低温冻土区进入多年冻土的热积累暂时以增高地温耗热为主 ,随着地温的增高 ,低温冻土区也可能发生强烈的冻土融化 . 展开更多
关键词 青藏公路 多年冻土 地温 融基 热积累
下载PDF
非氯植物基环保型融雪剂应用研究
4
作者 高勇卿 《价值工程》 2019年第13期170-172,共3页
高速公路除雪保畅一直是高速公路运营管理工作的重中之重,目前普遍采用的方法是通过机械、人工抛撒氯盐类融雪剂进行除雪融冰,氯盐类融雪剂在温度较低时消融结冰能力有所下降,且长期使用会对公路设施造成不同程度的腐蚀、侵蚀。为提升... 高速公路除雪保畅一直是高速公路运营管理工作的重中之重,目前普遍采用的方法是通过机械、人工抛撒氯盐类融雪剂进行除雪融冰,氯盐类融雪剂在温度较低时消融结冰能力有所下降,且长期使用会对公路设施造成不同程度的腐蚀、侵蚀。为提升除雪融冰的效果,保护公路设施,引进非氯植物基环保型融雪剂,并在沪陕高速西商段进行试点应用,通过实际应用及室内试验表明:植物基融雪产品相较于含氯融雪剂优势显著,融冰雪能力强于含氯融雪剂,环保无污染,对混凝土、钢材基本无侵蚀、腐蚀,对植物生长基本无害。为今后高速公路除雪保畅工作提供借鉴和参考。 展开更多
关键词 高速公路 除雪 非氯植物雪剂 应用
下载PDF
非氯盐型融雪剂在土壤中动态残留情况调查与分析
5
作者 李月 周广柱 +1 位作者 年玉欣 张倩 《中国园艺文摘》 2014年第4期220-222,共3页
以非氯植物基融雪剂为试验对象,以沈阳机场高速公路和沈本高速公路绿化带为监测样地,研究非氯植物基融雪剂在土壤中的动态残留情况及对土壤肥力的影响。采用液相色谱法进行测定,运用Spss及Excel进行数据分析。结果表明:土层深度、距离... 以非氯植物基融雪剂为试验对象,以沈阳机场高速公路和沈本高速公路绿化带为监测样地,研究非氯植物基融雪剂在土壤中的动态残留情况及对土壤肥力的影响。采用液相色谱法进行测定,运用Spss及Excel进行数据分析。结果表明:土层深度、距离、时间是影响非氯盐型融雪剂动态残留量的主要因素,作用力的大小顺序为时间>土层深度>距离;随着时间的增长、距高速公路边缘距离的增加、土层深度的加深,非氯盐型融雪剂在土壤中的含量不断减少,直至完全降解。 展开更多
关键词 非氯植物雪剂 土壤 动态残留
下载PDF
The Construction of Fusion Expression Vector Carrying GFP and TP of GGPPS from Ginkgo biloba L. 被引量:1
6
作者 李郑娜 杨春贤 +4 位作者 杨颖舫 成瑜 冯国庆 陈敏 廖志华 《Agricultural Science & Technology》 CAS 2010年第4期90-93,共4页
[Objective]The aim was to construct the fusion gene expression vector which consisted of GFP and TP gene of GGPPS from the Ginkgo biloba L.[Method]The transit-peptide(TP) sequence of GGPPS from cDNA of Ginkgo biloba... [Objective]The aim was to construct the fusion gene expression vector which consisted of GFP and TP gene of GGPPS from the Ginkgo biloba L.[Method]The transit-peptide(TP) sequence of GGPPS from cDNA of Ginkgo biloba L.was successfully cloned by using DNA recombination technology,which was then linked to the efficient plant expression vector p1304 + to construct the fusion gene expression vector p1304 +-TP.Then engineering strain EHA105-p1304 +-TP was constructed by transformed p1304 +-TP to Agrobacterium rhizogenes EHA105 using freeze-thaw method.[Result]The fusion gene expression vector which consisted of GFP and TP gene of GGPPS from the Ginkgo biloba L.and engineering strain EHA105-p1304 +-TP were successfully constructed.[Conclusion]It lays a foundation for further study of subcellular localization of TP transit peptide,which can help to clarify the molecular mechanism of a key step in biosynthesis of ginkgolides precursors,and also provides an important basis for the research on metabolic engineering of ginkgolide. 展开更多
关键词 Ginkgo biloba L. GGPPS Transit peptide Fusion gene
下载PDF
Detection of the SYT-SSX Fusion Gene in Synovial Sarcoma 被引量:1
7
作者 杨翎 范钦和 张炜明 《Journal of Nanjing Medical University》 2004年第1期36-39,共4页
Objective: To investigate the feasibility and significance of detecting SYT-SSX fusion gene in paraffin-embedded tissues of synovial sarcoma (SS) by reverse-transcriptase polymerase chain reaction(RT-PCR) methods. Met... Objective: To investigate the feasibility and significance of detecting SYT-SSX fusion gene in paraffin-embedded tissues of synovial sarcoma (SS) by reverse-transcriptase polymerase chain reaction(RT-PCR) methods. Methods: Twenty cases of SS tumors from archival materials were collected and all samples were formalin-fixed and paraffin-embedded (FFPE). SYT-SSX fusion transcript was detected by RT-PCR. Home-keeping gene Porphobilinogen Deaminase (PBGD) was regarded as internal control.Results: PBGD mRNA was detected in all 20 tumor cases (100%). SYT-SSX fusion transcript was detected in 18 tumor cases (90%). In 18 SYT-SSX positive SS cases, there are 12 present SYT-SSX1 fusion transcript and 6 present SYT-SSX2 fusion transcript. SYT-SSX1 fusion transcript can be seen in 9 monophasic SS and 3 biphasic SS. In 6 SYT-SSX2 positive SS cases, 4 were monophasic SS and 2 were biphasic. Conclusion: Detection of SYT-SSX fusion transcripts in FFPE tissues for diagnosis of SS is feasible and sensitive. Subtypes of SYT-SSX fusion gene may provide prognosis information. 展开更多
关键词 synovial sarcoma SYT-SSX fusion gene RT-PCR
下载PDF
Fluorescence molecular imaging system and fusion algorithm based on 2CCD camera
8
作者 王玉 王明泉 +1 位作者 杨晓峰 王艳翔 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第2期161-164,共4页
Infrared and visible light images can be obtained simultaneously by building fluorescence imaging system,which includes fluorescence excitation,images acquisition,mechanical part,image transmission and processing sect... Infrared and visible light images can be obtained simultaneously by building fluorescence imaging system,which includes fluorescence excitation,images acquisition,mechanical part,image transmission and processing section.This system studied the 2charge-coupled device(CCD)camera(AD-080CL)of the JAI company.Fusion algorithm of visible light and near infrared images was designed for the fluorescence imaging system with wavelet transform image fusion algorithm.In order to enhance the fluorescent moiety of the fusion image,the luminance value of the green component of the color image was changed.And using microsoft foundation classes(MFC)application architecture,the supporting software system was bulit in VS2010 environment. 展开更多
关键词 fluorescence imaging system image fusion wavelet transform microsoft foundation classes(MFC)
下载PDF
DETERMINGING BPA UNDER UNCERTAINTY ENVIRONMENTS AND ITS APPLICATION IN DATA FUSION 被引量:15
9
作者 Deng Yong Jiang Wen +2 位作者 Xu Xiaobin Li Qi Wang Dong 《Journal of Electronics(China)》 2009年第1期13-17,共5页
Dempster-Shafer (DS) theory of evidence has been widely used in many data fusion ap- plication systems. However, how to determine basic probability assignment, which is the main and the first step in evidence theory, ... Dempster-Shafer (DS) theory of evidence has been widely used in many data fusion ap- plication systems. However, how to determine basic probability assignment, which is the main and the first step in evidence theory, is still an open issue. In this paper, a new method to obtain Basic Probability Assignment (BPA) is proposed based on the similarity measure between generalized fuzzy numbers. In the proposed method, species model can be constructed by determination of the min, average and max value to construct a fuzzy number. Then, a new Radius Of Gravity (ROG) method to determine the similarity measure between generalized fuzzy numbers is used to calculate the BPA functions of each instance. Finally, the efficiency of the proposed method is illustrated by the classi- fication of Iris data. 展开更多
关键词 Data fusion Dempster-Shafer (DS) theory of evidence Basic Probability Assignment(BPA) Generalized fuzzy number Similarity measure
下载PDF
THE COEXPRESSION OF THE preS1(1-42) AND THE CORE(1-144)ANTIGEN OF HBV IN E.coli 被引量:1
10
作者 赵阳青 詹美云 《Chinese Medical Sciences Journal》 CAS CSCD 2002年第2期68-72,共5页
Objective.To study the therapeutic T cell vaccine for the treatment of chronic hepatitis B by improving the cellular immunization of HBsAg vaccine with the coexpression of the preS1(1-42)and the Core(1-144)anti-gen of... Objective.To study the therapeutic T cell vaccine for the treatment of chronic hepatitis B by improving the cellular immunization of HBsAg vaccine with the coexpression of the preS1(1-42)and the Core(1-144)anti-gen of HBV in E.coli.Methods.The genes of HBcAg (1-144)and preS1(1-42)were amplified and fused by PCR.This fused gene was inserted in the prokaryotic expression vector pET-11d and expre ssed in E.coli.Results.It was showed by SDS-PAGE that the pr otein molecular weight of the coexpr ession product was about 20kD,20%of all bacteria prote in.The monoclonal antibodies again st core and preS1antibody could re-act with this fused protein by Western-blot technique respectively.The fused gene was verified by sequencin g.Under the immune electron microscop y,this fused protein is typical particles of HBcAg but in an aggregated form.Conclusion.The results might aid for studying T c ell immunotherapeutic vaccine for c hronic hepatitis B. 展开更多
关键词 HBV preS1antigen HBCAG coexpression of fused gene
下载PDF
Effect of Riboflavin Operon Dosage on Riboflavin Productivity in Bacillus Subtilis 被引量:1
11
作者 陈涛 陈洵 +1 位作者 王靖宇 赵学明 《Transactions of Tianjin University》 EI CAS 2005年第1期1-5,共5页
After deregulating the purine and riboflavin synthesis in the Gram-positive bacterium Bacillus subtilis,it is critical to amplify riboflavin operon with appropriate dosage in the host strain for remarkable increase of... After deregulating the purine and riboflavin synthesis in the Gram-positive bacterium Bacillus subtilis,it is critical to amplify riboflavin operon with appropriate dosage in the host strain for remarkable increase of riboflavin production.Bacillus subtilis RH13, a riboflavin-producing strain, was selected as host strain in the construction of engineering strains by protoplast fusion. The integrative plasmid pRB63 and autonomous plasmid pRB49, pRB62 containing riboflavin operon of B.subtilis 24 were constructed and transformed into the host strain respectively. Increasing one operon copy in B.subtilis RH13 results in about 0.4 g/L improvement in riboflavin yield and the appropriate number of operon copies was about 7—8. Amplifying more riboflavin operons is of no use for further improvement of yield of riboflavin. Furthermore, excessive operon dosage results in metabolic unbalance and is fatal to the host cells producing riboflavin. 展开更多
关键词 Bacillus subtilis riboflavin operon protoplast fusion gene amplification
下载PDF
Studies on Pattern of Producing Transgenic Fish II. Several Elements Related to the Establishment of Transgenic Fish
12
作者 刘春巧 张永忠 +2 位作者 庄贵洵 孙效文 李云龙 《Developmental and Reproductive Biology》 1997年第2期21-27,共7页
A recombinant plasmid (pcMTsGH) containing the common carp methlothionein promoter (cMT) and salmon growth hormone gene (sGH) was microinjected into common carp fertilized eggs and embryos to optimize the conditions f... A recombinant plasmid (pcMTsGH) containing the common carp methlothionein promoter (cMT) and salmon growth hormone gene (sGH) was microinjected into common carp fertilized eggs and embryos to optimize the conditions for producing transgenic fish. Several key elements were found to have significant effects on the integration of exogenous gene. These elements include forms and doses of pcMTsGH gene microinjected, stages of embryo at which microinjection conducted and pretreatment of fertilized eggs for microinjection. The results show that, in producing transgenic fish, (1) the best time for microinjection is late onecell stage, (2) the most appropriate dose of pcMTsGH gene for microinjection is around 106~107 copies; (3) the hatching rate rises up when the gene is microinjected into the eggs whose chorions are removed, but the integration rate has no significant changes before and after the removal of egg chorions. 展开更多
关键词 transgenic fish integration rate hatching rate
下载PDF
Atypical Chronic Myeloid Leukaemia with Trisomy 13: a Case Report 被引量:1
13
作者 Guo-yu Hu Chao-hui Yuan Kui Tan Zhen-zhen Chen 《Chinese Medical Sciences Journal》 CAS CSCD 2011年第4期254-256,共3页
ATYPICAL chronic myeloid leukaemia (aCML), which shows both myeloproliferative and mye- Iodysplastic features, is a type of myeloprolif- erative/myelodysplastic disease as defined bythe World Health Organisation (... ATYPICAL chronic myeloid leukaemia (aCML), which shows both myeloproliferative and mye- Iodysplastic features, is a type of myeloprolif- erative/myelodysplastic disease as defined bythe World Health Organisation (WHO) classification of the myeloid neoplasms. Because of the presence of neutrophilic leukocytosis, aCML may resemble chronic myeIogenous leukemia (CML). However, in contrast with CML, aCML does not have the Philadelphia chromosome or the bcr/abl fusion gene. 展开更多
关键词 atypical chronic myeloid leukaemia trisomy 13 KARYOTYPE
下载PDF
A genetic algorithm for community detection in complex networks 被引量:6
14
作者 李赟 刘钢 老松杨 《Journal of Central South University》 SCIE EI CAS 2013年第5期1269-1276,共8页
A new genetic algorithm for community detection in complex networks was proposed. It adopts matrix encoding that enables traditional crossover between individuals. Initial populations are generated using nodes similar... A new genetic algorithm for community detection in complex networks was proposed. It adopts matrix encoding that enables traditional crossover between individuals. Initial populations are generated using nodes similarity, which enhances the diversity of initial individuals while retaining an acceptable level of accuracy, and improves the efficiency of optimal solution search. Individual crossover is based on the quality of individuals' genes; all nodes unassigned to any community are grouped into a new community, while ambiguously placed nodes are assigned to the community to which most of their neighbors belong. Individual mutation, which splits a gene into two new genes or randomly fuses it into other genes, is non-uniform. The simplicity and effectiveness of the algorithm are revealed in experimental tests using artificial random networks and real networks. The accuracy of the algorithm is superior to that of some classic algorithms, and is comparable to that of some recent high-precision algorithms. 展开更多
关键词 complex networks community detection genetic algorithm matrix encoding nodes similarity
下载PDF
Effect of direct electric current on wetting behavior of molten Bi on Cu substrate
15
作者 徐前刚 刘锡贝 张海峰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第8期1452-1457,共6页
The effect of direct electric current on the wetting behavior of molten Bi on Cu substrate at 370℃ was investigated by the sessile drop method. The wettability of molten Bi on Cu without an applied current is poor an... The effect of direct electric current on the wetting behavior of molten Bi on Cu substrate at 370℃ was investigated by the sessile drop method. The wettability of molten Bi on Cu without an applied current is poor and the spreading time required to form the steady-state contact angle (about 102°) is approximately 30 min. With the increase of the applied electric current, the spreading of molten Bi on Cu is accelerated significantly and the steady-state contact angle decreases considerably. The cross-section SEM micrographs of the solidified Bi droplet on Cu substrate show that the electric current has a marked effect on the convection of melt. Correspondingly, the application of an electric current obviously enhances the dissolution of Cu into Bi melt, which may change the wetting triple line configuration. The improvement of wettability induced by electric current is also related to the additional driving force for wetting provided by the electromagnetic pressure gradient force. 展开更多
关键词 WETTING DISSOLUTION surface and interface SPREADING
下载PDF
Effects of La substitution on microstructure and hydrogen storage properties of Ti−Fe−Mn-based alloy prepared through melt spinning 被引量:6
16
作者 Ze-ming YUAN Zhen QI +3 位作者 Ting-ting ZHAI Hong-zhang WANG Hai-yan WANG Yang-huan ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第10期3087-3095,共9页
The as-spun Ti_(1−x)La_(x)Fe_(0.8)Mn_(0.2)(x=0,0.01,0.03,0.06,0.09,molar fraction)alloys were prepared by melt spinning.The effects of La substitution for Ti on the microstructure,hydrogen storage kinetics and thermod... The as-spun Ti_(1−x)La_(x)Fe_(0.8)Mn_(0.2)(x=0,0.01,0.03,0.06,0.09,molar fraction)alloys were prepared by melt spinning.The effects of La substitution for Ti on the microstructure,hydrogen storage kinetics and thermodynamics of TiFe-type Ti−Fe−Mn-based alloy were investigated.The as-spun alloys hold the TiFe single phase,which transforms to TiFeH_(0.06),TiFeH,and TiFeH_(2) hydrides after hydrogenation.La substitution promotes the formation of micro-defects(such as dislocations and grain boundaries)in the alloys,thus facilitating hydrogen diffusion.In addition,the hydrogen storage kinetics properties are improved after introducing La element.With the rise of La content,the hydrogen storage capacity decreases firstly and then increases,but the absolute value of hydriding enthalpy change(|ΔH|)increases firstly and then reduces.When x=0.01,the maximum value of|ΔH|is obtained to be(25.23±0.50)kJ/mol for hydriding,and the alloy has the maximum hydrogen absorption capacity of(1.80±0.04)wt.%under the conditions of 323 K and 3 MPa. 展开更多
关键词 La substitution Ti−Fe−Mn-based alloy melt spinning hydrogen storage kinetics thermodynamics
下载PDF
Transient Expression of Human Growth Hormone in Mice Milk after in vivo Transfer of hGH Gcne
17
作者 劳维德 于雷 《Developmental and Reproductive Biology》 1995年第2期7-12,共6页
DNA expression constructs containing hGH gene directed by bovine αsl-casein gene regulatory sequences were injected into mouse heart or mammary glands in vivo. hGH expression was readily detected by radioimmunoassay ... DNA expression constructs containing hGH gene directed by bovine αsl-casein gene regulatory sequences were injected into mouse heart or mammary glands in vivo. hGH expression was readily detected by radioimmunoassay in milk of the nursing mice throughout lactation. Our results demonstrated the value of this simple and rapid approach in screening gene constructs and identifying transcription regulation sequences in vivo prior to the generation of transgenic animals. For the First time we report the successful expression in mammary gland via intracardial injection. 展开更多
关键词 Transient expression hGH gene in vivo DNA injection
下载PDF
A long-term-based handover decision algorithm for dense macro-femto coexistence networks
18
作者 刘诚毅 邢松 沈连丰 《Journal of Southeast University(English Edition)》 EI CAS 2017年第2期127-133,共7页
For the dense macro-femto coexistence networks scenario, a long-term-based handover(LTBH) algorithm is proposed. The handover decision algorithm is jointly determined by the angle of handover(AHO) and the time-tos... For the dense macro-femto coexistence networks scenario, a long-term-based handover(LTBH) algorithm is proposed. The handover decision algorithm is jointly determined by the angle of handover(AHO) and the time-tostay(TTS) to reduce the unnecessary handover numbers.First, the proposed AHO parameter is used to decrease the computation complexity in multiple candidate base stations(CBSs) scenario. Then, two types of TTS parameters are given for the fixed base stations and mobile base stations to make handover decisions among multiple CBSs. The simulation results show that the proposed LTBH algorithm can not only maintain the required transmission rate of users, but also effectively reduce the unnecessary numbers of handover in the dense macro-femto networks with the coexisting mobile BSs. 展开更多
关键词 handover decision algorithm angle of handover time-to-stay dense macro-femto coexistence networks mobile base station
下载PDF
浅谈井口房加固处理
19
作者 郭福君 《煤矿设计》 北大核心 2001年第1期46-47,共2页
介绍了某井口房围护墙裂缝状况 ,分析了裂缝原因 。
关键词 砖围护墙 不均匀沉降 裂缝 土地 高压旋喷桩 井口房 加固
下载PDF
Transforming Activity of a Novel Mutant of HPV16 E6E7 Fusion Gene
20
作者 Qiang Xie Zhi-xiang Zhou Ze-lin Li Yi Zeng 《Virologica Sinica》 SCIE CAS CSCD 2011年第3期206-213,共8页
An optimized recombinant HPV16 E6E7 fusion gene (HPV16 ofE6E7) was constructed according to codon usage for mammalian cell expression, and a mutant of HPV16 ofE6E7 fusion gene (HPV16 omfE6E7) was generated by site-dir... An optimized recombinant HPV16 E6E7 fusion gene (HPV16 ofE6E7) was constructed according to codon usage for mammalian cell expression, and a mutant of HPV16 ofE6E7 fusion gene (HPV16 omfE6E7) was generated by site-directed mutagenesis at L57G, C113R for the E6 protein and C24G, E26G for the E7 protein for HPV16 ofE6E7 [patent pending (CN 101100672)]. The HPV16 omfE6E7 gene constructed in this work not only lost the transformation capability to NIH 3T3 cells and tumorigenicity in SCID mice, but also maintained very good stability and antigenicity. These results suggests that the HPV16 omfE6E7 gene should undergo further study for application as a safe antigen-specific therapeutic vaccine for HPV16-associated tumors. 展开更多
关键词 Human papillomavirus (HPV) E6 E7 Gene optimization Gene mutation Transformation
下载PDF
上一页 1 2 3 下一页 到第
使用帮助 返回顶部