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卵巢肿瘤MRI定量诊断的临床价值 预览
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作者 林志军 《中国CT和MRI杂志》 2019年第3期113-115,126共4页
目的分析卵巢肿瘤MRI定量诊断的临床价值。方法选取2015年6月至2018年6月我院91例卵巢肿瘤病例资料,均于我院接受MRI检查,并行手术治疗,依据病理结果将其分为恶性组(n=35,病理证实为卵巢恶性肿瘤)、良性组(n=56,病理证实为卵巢良性肿瘤)... 目的分析卵巢肿瘤MRI定量诊断的临床价值。方法选取2015年6月至2018年6月我院91例卵巢肿瘤病例资料,均于我院接受MRI检查,并行手术治疗,依据病理结果将其分为恶性组(n=35,病理证实为卵巢恶性肿瘤)、良性组(n=56,病理证实为卵巢良性肿瘤),分析两组影像特点、MRI定量参数[容量转移常数(Ktrans)、速率常数(Kep)、血管外细胞间隙容积比(Ve)]、表观扩散系数(ADC)值,比较不同分期患者上述指标,分析定量参数、ADC区分良恶性卵巢肿瘤的效能。结果良性组Ktrans、Kep、Ve低于对照组,而ADC值高于对照组(P<0.05),良性组以Ⅰ型(流入型)为主,恶性组以Ⅲ型(流出型)为主;随FIGO分期增加,卵巢恶性肿瘤患者Ktrans、Kep、Ve增加,ADC值下降(P<0.05);定量参数中,Ktrans诊断卵巢恶性肿瘤的AUC值、特异度、最大约登指数最大,ADC、Kep次之,Ve最小,ADC诊断卵巢恶性肿瘤的灵敏度最高。结论 MRI定量参数为常规MRI诊断卵巢肿瘤、准确进行临床分期的重要补充,可为医师鉴别良恶性卵巢肿瘤提供帮助。 展开更多
关键词 卵巢肿瘤 MRI 定量 临床价值
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快速千伏切换能谱CT与QCT测定羊椎体骨密度的相关性及一致性研究 预览
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作者 陈民 张艳 袁慧书 《中国骨质疏松杂志》 CAS CSCD 北大核心 2019年第3期326-329,370共5页
目的利用羊椎体标本评价快速千伏切换能谱CT物质分离技术测定的骨松质骨密度与QCT测定的骨密度的一致性。方法新鲜羊椎体骨3副(共23个椎体),在快速千伏切换的能谱CT机上进行能谱模式扫描,利用物质分离技术获得椎体骨松质的羟基磷灰石含... 目的利用羊椎体标本评价快速千伏切换能谱CT物质分离技术测定的骨松质骨密度与QCT测定的骨密度的一致性。方法新鲜羊椎体骨3副(共23个椎体),在快速千伏切换的能谱CT机上进行能谱模式扫描,利用物质分离技术获得椎体骨松质的羟基磷灰石含量(骨密度),并在同一台CT机上对每副羊骨进行标准QCT扫描,用QCT骨密度分析软件获得对应感兴趣区内的椎体骨密度。采用Pearson相关性分析、配对样本t检验、组内相关系数及Bland-Altman法进行两种方法测量结果的相关性及一致性分析。结果能谱CT物质分离技术测得的羊椎体骨密度值为(286.7±103.8) mg/cm~3,显著低于QCT测量的骨密度值(321.3±123.6) mg/cm~3,但二者高度线性相关(r=0.989,P<0.001)。两种方法测量的骨密度值组内相关系数为0.974(P<0.001)。对原始数据进行对数转换后应用Bland-Altman分析,差值大部分位于差值平均值±1.96标准差范围内,提示两种测量一致性好。结论能谱CT物质分离技术测定的羊椎体骨密度与QCT测定的骨密度的一致性及相关性好,有望用于临床患者骨密度的评价及随访。 展开更多
关键词 体层摄影术 物质分离 定量 骨密度 骨质疏松
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紫外分光光度法测定大鼠血浆百草枯浓度的应用研究 预览
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作者 张新彧 雷亚莉 +2 位作者 黄杨 孙纪元 孙标 《当代医学》 2019年第11期6-8,共3页
目的通过评价紫外分光光度法测定大鼠中毒模型血清中百草枯浓度的可靠性,探讨其在临床百草枯中毒中的应用,建立一种快速灵敏的方法用于测定百草枯血药浓度的含量。方法血清600μL与20%三氯乙酸100μL混匀,以12000r/min离心10min,取0.2m... 目的通过评价紫外分光光度法测定大鼠中毒模型血清中百草枯浓度的可靠性,探讨其在临床百草枯中毒中的应用,建立一种快速灵敏的方法用于测定百草枯血药浓度的含量。方法血清600μL与20%三氯乙酸100μL混匀,以12000r/min离心10min,取0.2ml上清液,加1.8ml蒸馏水进行紫外分光光度法测定。结果血清中百草枯浓度线性范围为0.08~10μg/ml,回归方程为y=0.0935x+0.2964,其相关系数r为0.9955,回收率为90.63%~103.0%,RSD为3.6%~8.12%,日内及日间RSD波动于1.1%~5.19%和2.2%~6.04%,检测下限为0.05μg/ml。结论在样本处理过程中,紫外分光光度法采用三氯乙酸直接沉淀蛋白的方法处理大鼠血清样本,可靠性较高,杂峰干扰少,操作简便快捷,分析快速,结果准确。显示本方法符合生物样本分析测试的要求,为临床百草枯中毒患者的定量检测提供了一种简便准确的检测方法。 展开更多
关键词 百草枯 紫外分光光度法 血清 定量
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近红外光谱法快速测定榨菜中亚硝酸盐含量 预览
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作者 刘金阳 谢定 +1 位作者 杨倩圆 郑瑞娜 《食品工业科技》 CAS 北大核心 2019年第6期245-251,共7页
为研究利用傅立叶近红外光谱分析仪(NIRS)快速测定市售榨菜中亚硝酸盐的含量,先取榨菜样品按GB5009.33-2016测定其亚硝酸盐含量,再向榨菜样品中添加亚硝酸钠,制成亚硝酸钠浓度范围为0.122~39.0875 mg/kg,浓度梯度为0.66 mg/kg的60个样... 为研究利用傅立叶近红外光谱分析仪(NIRS)快速测定市售榨菜中亚硝酸盐的含量,先取榨菜样品按GB5009.33-2016测定其亚硝酸盐含量,再向榨菜样品中添加亚硝酸钠,制成亚硝酸钠浓度范围为0.122~39.0875 mg/kg,浓度梯度为0.66 mg/kg的60个样本校正集;与10个样本预测集采集对应的傅立叶近红外光谱曲线,将光谱信息与实际测量值相关联,利用TQ analyst建模软件进行计算分析。结果表明:建模最优预处理方法为一阶微分(1D)与Savitzky-Golay filter滤波平滑的组合预处理;比较分析偏最小二乘法(PLS)与主成分回归法(PCR)的亚硝酸盐样品建立的光谱模型,数据结果显示采用偏最小二乘法(PLS)的亚硝酸盐组分模型稳定性和预测能力更好;内部交叉验正均方差(RSMECV)、交叉验证决定系数(Rc)、外部预测均方根误差(RMSEP)、预测决定系数(RP)相关系数(r)分别为0.0310、0.9925、0.0141、0.9720、0.9378。经F检验与t检验,与国标所测结果无显著性差异。NIRS检测快速,无损便捷,可用于市售榨菜中亚硝酸盐残留量的定量检测。 展开更多
关键词 亚硝酸盐 榨菜 定量 近红外光谱 偏最小二乘法
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一种基于电信数据特点的新型特征挖掘方法 预览
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作者 吉晶 余凤丽 《电信工程技术与标准化》 2019年第3期61-65,共5页
电信数据特征具备含有缺失率、量纲相差大、内在相关性高等特点,现有特征挖掘技术无法完全适用。由此,本文设计了一种新型特征挖掘方法,从缺失率、标准差、相关性和重要度4个维度出发,分别拟合指标量化评估函数,并加权计算综合评分来挖... 电信数据特征具备含有缺失率、量纲相差大、内在相关性高等特点,现有特征挖掘技术无法完全适用。由此,本文设计了一种新型特征挖掘方法,从缺失率、标准差、相关性和重要度4个维度出发,分别拟合指标量化评估函数,并加权计算综合评分来挖掘特征。最后,本文使用实际业务数据,与业内最常用的随机森林特征挖掘方法进行比较,得出本文设计的方法从更多维度综合衡量,其特征挖掘结果更加科学合理,并且节约25%时间成本,实用性强。 展开更多
关键词 特征挖掘 电信数据 量化 综合评分
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Introgression of Two Drought QTLs into FUNAABOR-2 Early Generation Backcross Progenies Under Drought Stress at Reproductive Stage 预览
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作者 Christian Okechukwu ANYAOHA Mamadou FOFANA +2 位作者 Vernon GRACEN Pangirayi TONGOONA Semon MANDE 《水稻科学:英文版》 CSCD 2019年第1期32-41,共10页
FUNAABOR-2 is a popular Ofada rice variety grown in a large area under rainfed upland condition across western states of Nigeria.We used the combination of phenotypic and marker-assisted selection(MAS)to improve grain... FUNAABOR-2 is a popular Ofada rice variety grown in a large area under rainfed upland condition across western states of Nigeria.We used the combination of phenotypic and marker-assisted selection(MAS)to improve grain yield of FUNAABOR-2 under drought stress(DS)at the reproductive stage via introgression of two drought quantitative trait loci(QTLs),qDTY12.1 and qDTY2.3.Foreground selection was carried out using peak markers RM511 and RM250,associated with qDTY12.1 and qDTY2.3,respectively,followed by recombinant selection with RM28099 and RM1261 distally flanking qDTY12.1.Furthermore,BC1F2-derived introgressed lines and their parents were evaluated under DS and non-stress(NS)conditions during the 2015–2016 dry season.Overall reduction of grain yield under DS compared to NS was recorded.Introgressed lines with qDTY12.1 and qDTY2.3 combinations showed higher yield potential compared to lines with single or no QTL under DS,indicating significant positive interactions between the two QTLs under the FUNAABOR-2 genetic background.Pyramiding of qDTY12.1 and qDTY2.3 in the FUNAABOR-2 genetic background led to higher grain yield production under DS and NS. 展开更多
关键词 DROUGHT foreground selection introgressed line peak marker yield potential rice quantitative TRAIT locus
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Accuracy improvement of calibration-free laser-induced breakdown spectroscopy
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作者 付洪波 倪志波 +2 位作者 王华东 贾军伟 董凤忠 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第3期6-15,共10页
Calibration-free laser-induced breakdown spectroscopy can overcome the matrix effect and the huge application prospects of in situ and on-line measurement,so it has been studied and applied to many analytical samples ... Calibration-free laser-induced breakdown spectroscopy can overcome the matrix effect and the huge application prospects of in situ and on-line measurement,so it has been studied and applied to many analytical samples by numerous researchers since it was first proposed in 1999.However,its accuracy is always lower than other analytical techniques and traditional quantitative analysis methods of laser-induced breakdown spectroscopy.The goal of this paper is to review the improvement of accuracy in the experimental setup and spectral analysis,especially after 2010,but not limited to it.The main contents include the accurate measurement of spectral intensity,the spatial and temporal window of local thermodynamic equilibrium and the accurate calculation of temperature and electron density.Due to the requirement of one or more standard samples,the combination of standard samples and CF-LIBS is discussed as a separate section.Finally,a simple conclusion is offered to relevant researchers who want to use CF-LIBS for quantitative analysis. 展开更多
关键词 CF-LIBS QUANTITATIVE analysis ACCURACY SELF-ABSORPTION local THERMODYNAMIC EQUILIBRIUM
Identification of QTLs and Validation of qCd-2 Associated with Grain Cadmium Concentrations in Rice 预览
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作者 LIU Wenqiang PAN Xiaowu +6 位作者 LI Yongchao DUAN Yonghong MIN Jun LIU Sanxiong LIU Licheng SHENG Xinnian LI Xiaoxiang 《水稻科学:英文版》 CSCD 2019年第1期42-49,共8页
Cadmium(Cd)is one of heavy metals harmful to human health.As rice is the main staple food in Asia and Cd is easily contaminated in rice,the molecular regulation of Cd accumulation should be explored.In this study,a re... Cadmium(Cd)is one of heavy metals harmful to human health.As rice is the main staple food in Asia and Cd is easily contaminated in rice,the molecular regulation of Cd accumulation should be explored.In this study,a recombinant inbred population derived from Xiang 743/Katy was grown in Cd-polluted fields and used to map the quantitative trait loci(QTLs)for Cd accumulation in rice grains.We identified seven QTLs distributed on chromosomes 2,3,6,7,8 and 10.These QTLs displayed phenotypic variances of 58.50%and 40.59%in 2014 and 2015,respectively.Two QTLs,qCd-2 and qCd-7,were identified in both the two years.qCd-2 was detected on the interval of RM250–RM207 on chromosome 2,with an LOD of 2.51 and a phenotypic contribution of 13.75%in 2014,and an LOD of 3.35 and a phenotypic contribution of 14.16%in 2015.qCd-7 co-localized with the cloned qCdT7 on chromosome 7 and may represent the correct candidate.The other five QTLs were detected only in one year.To further confirm the effects of qCd-2,a residual heterozygous line designated as RHL945,with a heterozygous interval of RM263–RM207 on chromosome 2,was selected from the recombinant inbred population and used to develop an F2 population consisting of 155 individual plants.By incorporating further simple sequence repeat markers into the segmental linkage map of the target region,qCd-2 was delimited in the interval of RM5404–RM3774,with an LOD value of 4.38 and a phenotypic contribution of 15.52%.These results reflected the genetic regulation of grain Cd in rice and paved the way for the future cloning of qCd-2. 展开更多
关键词 CADMIUM recombinant INBRED line quantitative TRAIT LOCUS RICE simple sequence REPEAT
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Detection of heavy metals in water samples by laser-induced breakdown spectroscopy combined with annular groove graphite flakes
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作者 方丽 赵南京 +5 位作者 马明俊 孟德硕 贾尧 黄行九 刘文清 刘建国 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第3期16-22,共7页
The use of laser-induced breakdown spectroscopy(LIBS)for the analysis of heavy metals in water samples is investigated.Some factors such as splashing,surface ripples,extinction of emitted intensity,and a shorter plasm... The use of laser-induced breakdown spectroscopy(LIBS)for the analysis of heavy metals in water samples is investigated.Some factors such as splashing,surface ripples,extinction of emitted intensity,and a shorter plasma lifetime will influence the results if the water sample is directly measured.In order to avoid these disadvantages and the‘coffee-ring effect’,hydrophilic graphite flakes with annular grooves were used for the first time to enrich and concentrate heavy metals in water samples before being analyzed by LIBS.The proposed method and procedure have been evaluated to concentrate and analyze cadmium,chromium,copper,nickel,lead,and zinc in a water sample.The correlation coefficients were all above 0.99.The detection limits of 0.029,0.087,0.012,0.083,0.125,and 0.049 mgl^-1 for Cd,Cr,Cu,Ni,Pb,and Zn,respectively,were obtained in samples prepared in a laboratory.With this structure,the heavy metals homogeneously distribute in the annular groove and the relative standard deviations are all below 6%.This method is very convenient and suitable for online in situ analysis of heavy metals. 展开更多
关键词 LASER-INDUCED BREAKDOWN spectroscopy quantitative analysis heavy metals GRAPHITE FLAKE
基于模拟量反馈的加氯机开度自动控制系统 预览
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作者 陈燕兵 陶灵兵 《工业控制计算机》 2019年第1期58-59,61共3页
提供了一种基于模拟量反馈的加氯机开度自动控制方法,针对无模拟量输出的加氯机改进,利用加氯机电位器内的电阻随加氯机工作状态变化呈现抛物线变化的物理特性,运用外加电源的方式将加氯机工作状态的物理特性通过电流的形式传入可编程... 提供了一种基于模拟量反馈的加氯机开度自动控制方法,针对无模拟量输出的加氯机改进,利用加氯机电位器内的电阻随加氯机工作状态变化呈现抛物线变化的物理特性,运用外加电源的方式将加氯机工作状态的物理特性通过电流的形式传入可编程逻辑控制器PLC的模拟量模块,然后通过组态InTouch软件在计算机画面上显示出加氯机开度的定量值,对加氯机开度自动控制,开度定位准确率高,操作简单方便,节省了设备成本。 展开更多
关键词 模拟量反馈 定量 PLC INTOUCH
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《生化分离技术》课程教学质量的定量化研究 预览
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作者 张惠燕 《科技通报》 2019年第3期250-254,共5页
随着近年来高校招生规模的扩大,教学质量的评价越来越受到人们的关注,高校教学质量直接影响着高校人才的产出质量,如何准确评价高校教学质量已成为亟待解决的首要问题,准确定量评价教学质量有利于改进教学方法。本文对高校教学质量评估... 随着近年来高校招生规模的扩大,教学质量的评价越来越受到人们的关注,高校教学质量直接影响着高校人才的产出质量,如何准确评价高校教学质量已成为亟待解决的首要问题,准确定量评价教学质量有利于改进教学方法。本文对高校教学质量评估体系进行了探讨,总结了一些适合于完善教学评估体系的技术方法,研究了从教学需求、结构、内容、条件及实施这五方面基于定量模型的高校教学质量评估,结果表明,用量化模型评价高校教学质量效果较好,可以更全面地分析各种因素的影响,更有效,科学地分析教学质量。 展开更多
关键词 定量化 课程教学质量
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Rockery Protection Under the Framework of World Heritage Protection 预览
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作者 CHEN Wanyu QIN Ke 《景观研究:英文版》 2019年第1期61-64,共4页
In this paper,the content of rockery protection was discussed through the analysis of a series of documents such as the convention,declaration,and regulations concerning heritage protection in accordance with the prin... In this paper,the content of rockery protection was discussed through the analysis of a series of documents such as the convention,declaration,and regulations concerning heritage protection in accordance with the principles of authenticity and integrity.Through the analysis of the influence factors of the rockery and its environment,it is proposed that the rockery protection should strengthen environmental protection on the basis of the protection of the body of a rockery.From the perspectives of structure,skill,materials and function,the contents of the rockery protection and the human settlement environment where the rockery is located,the external environment and internal environment of the rockery space were analyzed,and the contents of the rockery protection were preliminarily proposed. 展开更多
关键词 ROCKERY PROTECTION World HERITAGE QUANTITATIVE study REPAIR
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A targeted QTL analysis for fiber length using a genetic population between two introgressed backcrossed inbred lines in upland cotton(Gossypium hirsutum) 预览
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作者 Guoyuan Liua Wenfeng Pei +10 位作者 Dan Li Jianjiang Ma Yupeng Cui Nuohan Wang Jikun Song Man Wu Libei Li Xinshan Zang Shuxun Yu Jinfa Zhang Jiwen Yu 《作物学报:英文版》 CAS CSCD 2019年第3期273-282,共10页
Cotton fiber is the most important natural raw material for the textile industry, and fiber length(FL) is one of the most important traits in cotton.Quantitative trait locus(QTL)mapping based on high-density genetic m... Cotton fiber is the most important natural raw material for the textile industry, and fiber length(FL) is one of the most important traits in cotton.Quantitative trait locus(QTL)mapping based on high-density genetic maps is an efficient approach to identify genetic regions for FL.In our study, two backcrossed inbred lines(BILs) were chosen as parents to construct a high-density genetic map in F2 which was used to fine map FL QTL in F2:3 population.The genetic map had a total size of 3462.8 cM, containing 9182 singlenucleotide polymorphisms(SNPs) based on genotyping-by-sequencing.Two FL related stable QTL were identified on two chromosomes(qFL-A08–1 on A08 and qFL-D03–1 on D03),and qFL-A08–1 was confirmed by a meta-analysis.Utilizing previously obtained RNA-seq data for the two BILs and qRT-PCR analysis, two candidate genes annotated as cytochrome b5(CB5, Gh_A08 G1729) and microtubule end-binding 1 C(EB1C, Gh_D03 G0232) that may regulate FL during the fiber elongation stage were identified.In addition, nine recombination hotspots in this population were found.The results of this study will provide an important foundation for further studies on the molecular and genetic regulation of fiber elongation. 展开更多
关键词 GOSSYPIUM Single-nucleotide polymorphism Fiber length Quantitative TRAIT LOCUS
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Variation and heritability of morphological and physiological traits among Leymus chinensis genotypes under different environmental conditions
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作者 YANG Xue LI Junpeng +5 位作者 ZHAO Tingting MO Lidong ZHANG Jianli REN Huiqin ZHAO Nianxi GAO Yubao 《干旱区科学:英文版》 SCIE CSCD 2019年第1期66-74,共9页
Intraspecific trait variation and heritability in different environmental conditions not only suggest a potential for an evolutionary response but also have important ecological consequences at the population, communi... Intraspecific trait variation and heritability in different environmental conditions not only suggest a potential for an evolutionary response but also have important ecological consequences at the population, community, and ecosystem levels. However, the contribution of quantitative trait variation within a grassland species to evolutionary responses or ecological consequences is seldom documented. Leymus chinensis is an important dominant species in semi-arid grasslands of China, which has seriously suffered from drought and high temperature stresses in recent decades. In the present study, we measured variation and heritability of 10 quantitative traits, namely the number of tillers, maximum shoot height, number of rhizomes, maximum rhizome length, rhizome mass, aboveground mass, root mass, maximum net photosynthetic rate(Pmax), specific leaf area(SLA), and leaf length to leaf width ratio(LL/LW), for 10 genotypes of L. chinensis under one non-stress(Ck) condition and three environmental stress conditions(i.e., drought(Dr), high temperature(Ht), and both drought and high temperature(DrHt)). Result indicated that(1) the interaction of genotype and environmental condition(G×E) was significant for 6 traits but not significant for the other 4 traits as shown by two-way analysis of variance(ANOVA), suggesting that different selection forces were placed for different traits on the factors dominating phenotypic responses to different environmental conditions. Moreover, these significant G×E effects on traits indicated significantly different phenotypic adaptive responses among L. chinensis genotypes to different environmental conditions. Additionally, individuals could be grouped according to environmental condition rather than genotype as shown by canonical discriminant analysis, indicating that environmental condition played a more important role in affecting phenotypic variation than genotype;(2) by one-way ANOVA, significant differences among L. chinensis genotypes were found in all 10 traits under Ck and Dr con 展开更多
关键词 LEYMUS chinensis genotype quantitative TRAIT VARIATION HERITABILITY drought high temperature
An efficient procedure in quantitative analysis using laser-induced breakdown spectroscopy
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作者 潘从元 何娇 +3 位作者 王广谦 杜学维 刘永斌 苏亚辉 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第3期92-97,共6页
Laser-induced breakdown spectroscopy has become a general-purpose technique,and internal standard calibration is a common method for quantitative analysis.Calibration models should be reconstructed for different syste... Laser-induced breakdown spectroscopy has become a general-purpose technique,and internal standard calibration is a common method for quantitative analysis.Calibration models should be reconstructed for different systems and application environments.This study presents an efficient procedure in the construction and selection of calibration models for LIBS analysis.The procedure concludes data preprocess,calibration model construction,and concentration calculation.These steps can be programmed without manual intervention.Results of the quantitative analysis of Ni-based alloys using the proposed procedure are presented in this study.Ten elements are calibrated,and most have an average relative standard error of less than 10%.The proposed procedure is an effective process for constructing and selecting calibration models. 展开更多
关键词 LASER-INDUCED BREAKDOWN SPECTROSCOPY QUANTITATIVE analysis PROCEDURE ALLOYS
Deformation Mechanism and Vertical Sealing Capacity of Fault in the Mudstone Caprock
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作者 Xiaofei Fu Lingyu Yan +1 位作者 Lingdong Meng Xiaobo Liu 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第2期367-375,共9页
The petrophysical property of mudstone often transforms from ductile to brittle in the process of burial-uplift. The deformation mechanism of fault in brittle and ductile mudstone caprock is different, which leads to ... The petrophysical property of mudstone often transforms from ductile to brittle in the process of burial-uplift. The deformation mechanism of fault in brittle and ductile mudstone caprock is different, which leads to the formation of different types of fault zone structure. Different methods are required to evaluate the sealing mechanism of those fault zones. Based on the caprock deformation mechanism, fault sealing mechanism, quantitative evaluation method of vertical fault sealing capacity is put forward in this study. Clay smear is formed in the process of plastic deformation and its continuity controls the sealing capacity of fault. The outcrop and oil field data have confirmed that when sealing parameter SSF is less than 4–7, the clay smear becomes discontinuous and then oil and gas go through the caprock and migrate vertically. Quantities of fractures are formed in mudstone in the process of brittle deformation. The fracture density increases with the increase of the fault displacement. When the fractures are connected, oil and gas go through the caprock and migrate vertically. The connectivity of fault depends on the displacement and the thickness of caprock. On the basis of the above, a method is put forward to quantify the connectivity of fault with the juxtaposition thickness of caprock after faulting. The research on the juxtaposition thickness of caprock after faulting of the member II of Dongying Formation in Nanpu depression and the distribution of oil and gas indicates when the juxtaposition thickness of caprock is less than 96.2 m, the fault becomes leaking vertically. In the lifting stage, with the releasing and unloading of the stress, the caprock becomes brittle generally and then forms through going fault which will lead to a large quantity of oil and gas migrate vertically. 展开更多
关键词 MUDSTONE FAULT DEFORMATION brittle-ductile SHALE SMEAR CJT QUANTITATIVE evaluation
QTG-Seq Accelerates QTL Fine Mapping through QTL Partitioning and Whole-Genome Sequencing of Bulked Segregant Samples
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作者 Hongwei Zhang Xi Wang +15 位作者 Qingchun Pan Pei Li Yunjun Liu Xiaoduo Lu Wanshun Zhong Minqi Li Linqian Han Juan Li Pingxi Wang Dongdong Li Yan Liu Qing Li Fang Yang Yuan-Ming Zhang Guoying Wang Lin Li 《分子植物:英文版》 SCIE CAS CSCD 2019年第3期426-437,共12页
Deciphering the genetic mechanisms underlying agronomic traits is of great importance for crop improvement. Most of these traits are controlled by multiple quantitative trait loci (QTLs), and identifying the underlyin... Deciphering the genetic mechanisms underlying agronomic traits is of great importance for crop improvement. Most of these traits are controlled by multiple quantitative trait loci (QTLs), and identifying the underlying genes by conventional QTL fine-mapping is time-consuming and labor-intensive. Here, we devised a new method, named quantitative trait gene sequencing (QTG-seq), to accelerate QTL fine-mapping. QTGseq combines QTL partitioning to convert a quantitative trait into a near-qualitative trait, sequencing of bulked segregant pools from a large segregating population, and the use of a robust new algorithm for identifying candidate genes. Using QTG-seq, we fine-mapped a plant-height QTL in maize (Zea mays L.), qPH7, to a 300-kb genomic interval and verified that a gene encoding an NF-YC transcription factor was the functional gene. Functional analysis suggested that qPH7-encoding protein might influence plant height by interacting with a CO-like protein and an AP2 domain-containing protein. Selection footprint ana卜 ysis indicated that qPH7 was subject to strong selection during maize improvement. In summary, QTG-seq provides an efficient method for QTL fine-mapping in the era of “big data". 展开更多
关键词 quantitative TRAIT LOCUS QTL QTL FINE-MAPPING WHOLE genome sequencing plant height
Comparative Study on Coastal Depth Inversion Based on Multi-source Remote Sensing Data 预览
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作者 LU Tianqi CHEN Shengbo +3 位作者 TU Yuan YU Yan CAO Yijing JIANG Deyang 《中国地理科学:英文版》 SCIE CSCD 2019年第2期192-201,共10页
Coastal depth is an important research focus of coastal waters and is also a key factor in coastal environment. Dongluo Island in South China Sea was taken as a typical study area. The band ratio model was established... Coastal depth is an important research focus of coastal waters and is also a key factor in coastal environment. Dongluo Island in South China Sea was taken as a typical study area. The band ratio model was established by using measured points and three multispectral images of Landsat-8, SPOT-6(Systeme Probatoire d’Observation de la Terre, No.6) and WorldView-2. The band ratio model with the highest accuracy is selected for the depth inversion respectively. The results show that the accuracy of SPOT-6 image is the highest in the inversion of coastal depth. Meanwhile, analyzing the error of inversion from different depth ranges, the accuracy of the inversion is lower in the range of 0–5 m because of the influence of human activities. The inversion accuracy of 5–10 m is the highest, and the inversion error increases with the increase of water depth in the range of 5–20 m for the three kinds of satellite images. There is no linear relationship between the accuracy of remote sensing water depth inversion and spatial resolution of remote sensing data, and it is affected by performance and parameters of sensor. It is necessary to strengthen the research of remote sensor in order to further improve the accuracy of inversion. 展开更多
关键词 COASTAL WATERS remote SENSING quantitative INVERSION satellite ACCURACY comparison
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Detection of K in soil using time-resolved laser-induced breakdown spectroscopy based on convolutional neural networks
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作者 吕程序 王博 +3 位作者 姜训鹏 张俊宁 牛康 苑严伟 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第3期108-113,共6页
One of the technical bottlenecks of traditional laser-induced breakdown spectroscopy(LIBS)is the difficulty in quantitative detection caused by the matrix effect.To troubleshoot this problem,this paper investigated a ... One of the technical bottlenecks of traditional laser-induced breakdown spectroscopy(LIBS)is the difficulty in quantitative detection caused by the matrix effect.To troubleshoot this problem,this paper investigated a combination of time-resolved LIBS and convolutional neural networks(CNNs)to improve K determination in soil.The time-resolved LIBS contained the information of both wavelength and time dimension.The spectra of wavelength dimension showed the characteristic emission lines of elements,and those of time dimension presented the plasma decay trend.The one-dimensional data of LIBS intensity from the emission line at 766.49 nm were extracted and correlated with the K concentration,showing a poor correlation of R^2c=0.0967,which is caused by the matrix effect of heterogeneous soil.For the wavelength dimension,the two-dimensional data of traditional integrated LIBS were extracted and analyzed by an artificial neural network(ANN),showing R^2v=0.6318 and the root mean square error of validation(RMSEV)=0.6234.For the time dimension,the two-dimensional data of time-decay LIBS were extracted and analyzed by ANN,showing R^2v=0.7366 and RMSEV=0.7855.These higher determination coefficients reveal that both the non-K emission lines of wavelength dimension and the spectral decay of time dimension could assist in quantitative detection of K.However,due to limited calibration samples,the two-dimensional models presented over-fitting.The three-dimensional data of time-resolved LIBS were analyzed by CNNs,which extracted and integrated the information of both the wavelength and time dimension,showing the R^2v=0.9968 and RMSEV=0.0785.CNN analysis of time-resolved LIBS is capable of improving the determination of K in soil. 展开更多
关键词 quantitative DETECTION potassium(K) SOIL TIME-RESOLVED LASER-INDUCED breakdown spectroscopy(LIBS) convolutional neural networks(CNNs)
Improvement of quantitative analysis of molybdenum element using PLS-based approaches for laser-induced breakdown spectroscopy in various pressure environments
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作者 刘佳敏 吴鼎 +4 位作者 付彩龙 海然 于潇 孙立影 丁洪斌 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第3期140-147,共8页
An experimental setup has been designed and realized in order to optimize the characteristics of laser-induced breakdown spectroscopy system working in various pressure environments.An approach combined the normalizat... An experimental setup has been designed and realized in order to optimize the characteristics of laser-induced breakdown spectroscopy system working in various pressure environments.An approach combined the normalization methods with the partial least squares(PLS)method are developed for quantitative analysis of molybdenum(Mo)element in the multi-component alloy,which is the first wall material in the Experimental Advanced Superconducting Tokamak.In this study,the different spectral normalization methods(total spectral area normalization,background normalization,and reference line normalization)are investigated for reducing the uncertainty and improving the accuracy of spectral measurement.The results indicates that the approach of PLS based on inter-element interference is significantly better than the conventional PLS methods as well as the univariate linear methods in the various pressure for molybdenum element analysis. 展开更多
关键词 laser induced BREAKDOWN SPECTROSCOPY MOLYBDENUM vacuum NORMALIZATION partial least SQUARES method quantitative analysis
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