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日语[たち]汉语“们”与确数数量词的同现研究
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作者 郭蓉菲 《日语学习与研究》 CSSCI 2019年第3期56-64,共9页
本文从日汉对比的角度,根据代名词、固有名词、普通名词等不同情况,探讨了[たち]和“们”究竟是集合标记还是复数标记,解释了[たち]和“们”前接这三类名词时与确数数量词同现或不同现的原因,并概括了集合标记、复数标记和确数数量词的... 本文从日汉对比的角度,根据代名词、固有名词、普通名词等不同情况,探讨了[たち]和“们”究竟是集合标记还是复数标记,解释了[たち]和“们”前接这三类名词时与确数数量词同现或不同现的原因,并概括了集合标记、复数标记和确数数量词的各自特征:集合标记存在代表性成员,且个体之间具有可区别性;复数标记不存在代表性成员,且个体之间具有不可区别性;确数数量词具有定量性的特征,且所修饰的名词必须同属性。 展开更多
关键词 确数数量词 集合标记 复数标记 定量 不定量
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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Quantitative prediction of oil saturation of unconsolidated sandstone reservoir based on time-lapse seismic “relative difference method”: Taking Zeta oil field in West Africa as an example 预览
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作者 LU Hongmei XU Hai +1 位作者 WO Yujin GU Ning 《石油勘探与开发:英文版》 2019年第2期426-434,共9页
In view of the disadvantage that the absolute difference of time-lapse seismic(the difference between monitoring data and base data) is not only related to the change of oil saturation, but also closely related to the... In view of the disadvantage that the absolute difference of time-lapse seismic(the difference between monitoring data and base data) is not only related to the change of oil saturation, but also closely related to the thickness of reservoir, a time-lapse seismic "relative difference method"(the ratio of monitoring data to base data) not affected by the thickness of reservoir but only related to the change of fluid saturation, is proposed through seismic forward modeling after fluid displacement simulation. Given the same change of fluid saturation, the absolute difference of time-lapse seismic conforms to the law of "tuning effect" and seismic reflection of "thin bed", and the remaining oil prediction method based on absolute difference of time-lapse seismic is only applicable to the reservoirs with uniform thickness smaller than the tuning thickness or with thickness greater than the tuning thickness. The relative difference of time-lapse seismic is not affected by reservoir thickness, but only related to the change of fluid saturation. It is applicable to all the deep-sea unconsolidated sandstone reservoirs which can exclude the effect of pressure, temperature, pore type and porosity on seismic. Therefore, the relation between the relative difference of time-lapse seismic and the change of fluid saturation, which is obtained from seismic forward modeling after Gassmann fluid displacement simulation, can be used to quantitatively predict the change of reservoir water saturation and then the distribution of the remaining oil. The application of this method in deep sea Zeta oil field in west Africa shows that it is reasonable and effective. 展开更多
关键词 time-lapse seismic remaining OIL quantitative prediction unconsolidated sandstone reservoir fluid displacement absolute DIFFERENCE RELATIVE DIFFERENCE ZETA OIL field WEST AFRICA
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洗衣机中洗涤剂添加装置专利技术发展综述 预览
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作者 孟祥杰 杨赛 《科技创新与应用》 2019年第20期11-12,16共3页
近年来,洗衣机智能化程度越来越高,洗涤剂添加装置的自动化程度显得愈发重要。文章从专利文献的视角对洗涤剂添加装置的技术发展进行了统计分析,总结了国内外专利的专利申请趋势、主要申请人分布,并从中得到一定规律。
关键词 洗衣机 洗涤剂添加 自动 定量
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Titanium dioxide as an adsorbent to enhance the detection ability of near-infrared diffuse reflectance spectroscopy
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作者 Shuyu Wang Jin Zhang +1 位作者 Wensheng Cai Xueguang Shao 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第5期1024-1026,共3页
A method for quantitative determination of fish sperm deoxyribonucleic acid(fsDNA)was developed by using titanium dioxide(TiO2)as an adsorbent and near-infrared diffuse reflectance spectroscopy(NIRDRS).The selective e... A method for quantitative determination of fish sperm deoxyribonucleic acid(fsDNA)was developed by using titanium dioxide(TiO2)as an adsorbent and near-infrared diffuse reflectance spectroscopy(NIRDRS).The selective enrichment of fsDNA was proved by comparing the adsorption efficiency of bovine serum albumin,tyrosine and tryptophan,and the low adsorption background of TiO2 was illustrated by comparing the spectra of four commonly-used inorganic adsorbents(alkaline aluminium oxide,neutral aluminium oxide,nano-hydroxyapatite and silica).The spectral feature of fsDNA can be clearly observed in the spectrum of the sample.Partial least squares(PLS)model was built for quantitative determination of fsDNA using 28 solutions,and 13 solutions with interferences were used for validation of the model.The results showed that the correlation coefficient(R)between the predicted and the reference concentration is 0.9727 and the recoveries of the validation samples are in the range of 98.2%-100.7%. 展开更多
关键词 NEAR-INFRARED DIFFUSE reflectance spectroscopy Quantitative model DETECTION ABILITY Titanium dioxide Fish SPERM DNA
Application of Fingerprint Combined with QAMS in Quality Evaluation of Zhenrongdan Mixture 预览
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作者 Jianping ZHANG Dong WANG Xuemei ZHOU 《药用植物研究(英文版)》 2019年第2期50-53,共4页
[Objectives] The research aimed to evaluate the quality of Zhenrongdan mixture by fingerprint combining QAMS.[Methods] The quality evaluation method was established and validated with echinacoside as internal referenc... [Objectives] The research aimed to evaluate the quality of Zhenrongdan mixture by fingerprint combining QAMS.[Methods] The quality evaluation method was established and validated with echinacoside as internal reference to determine the contents of other components(ferulic acid, salvianolic acid B, and icariin) according to the relative correction factor. The accuracy and feasibility of QAMS were evaluated by comparison on the results between the measured value and calculation value by external standard method and QAMS.[Results] A common pattern of characteristic fingerprint of Zhenrongdan mixture by HPLC was established. Thirteen common peaks were identified, and they account for 91% of the total peak area, and four components were verified in five batches of Zhenrongdan mixture. Good similarities with correlation coefficients higher than 0.99 were found in the fingerprints. There was no significant difference between the quantitative results of the four ingredients in the five batches by external standard method and QAMS.[Conclusions] The method of fingerprint combined with QAMS could be used for the quality control of multiple components determination and fingerprint chromatography for Zhenrongdan mixture. 展开更多
关键词 FINGERPRINT QUANTITATIVE analysis of multi-components by single MARKER (QAMS) Zhenrongdan MIXTURE Quality control CORRECTION FACTOR
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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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Recent Progress in Dual-Polarization Radar Research and Applications in China 预览
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作者 Kun ZHAO Hao HUANG +11 位作者 Mingjun WANG Wen-Chau LEE Gang CHEN Long WEN Jing WEN Guifu ZHANG Ming XUE Zhengwei YANG Liping LIU Chong WU Zhiqun HU Sheng CHEN 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第9期961-974,共14页
Dual-polarization(dual-pol)radar can measure additional parameters that provide more microphysical information of precipitation systems than those provided by conventional Doppler radar.The dual-pol parameters have be... Dual-polarization(dual-pol)radar can measure additional parameters that provide more microphysical information of precipitation systems than those provided by conventional Doppler radar.The dual-pol parameters have been successfully utilized to investigate precipitation microphysics and improve radar quantitative precipitation estimation(QPE).The recent progress in dual-pol radar research and applications in China is summarized in four aspects.Firstly,the characteristics of several representative dual-pol radars are reviewed.Various approaches have been developed for radar data quality control,including calibration,attenuation correction,calculation of specific differential phase shift,and identification and removal of non-meteorological echoes.Using dual-pol radar measurements,the microphysical characteristics derived from raindrop size distribution retrieval,hydrometeor classification,and QPE is better understood in China.The limited number of studies in China that have sought to use dual-pol radar data to validate the microphysical parameterization and initialization of numerical models and assimilate dual-pol data into numerical models are summarized.The challenges of applying dual-pol data in numerical models and emerging technologies that may make significant impacts on the field of radar meteorology are discussed. 展开更多
关键词 DUAL-POLARIZATION RADAR QUANTITATIVE PRECIPITATION estimation PRECIPITATION MICROPHYSICS DROP size distribution numerical model
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齿轮泵动态液压力的研究与分析 预览
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作者 孙付春 李玉龙 +1 位作者 黄尔宇 钟飞 《机械设计与制造》 北大核心 2019年第6期116-119,共4页
为克服齿轮泵液压力静态计算方法的局限性和结果不精确,推导了过渡区起始角和终止角的动态计算式,建立了液压力分布式,积分出从动轮上动态液压力的计算式;并在三种结构下,就液压力的动态和静态计算结果,进行比较和分析。结果表明:进出... 为克服齿轮泵液压力静态计算方法的局限性和结果不精确,推导了过渡区起始角和终止角的动态计算式,建立了液压力分布式,积分出从动轮上动态液压力的计算式;并在三种结构下,就液压力的动态和静态计算结果,进行比较和分析。结果表明:进出口的夹角越小越好,所出现的55°和85°的阶梯临界点为进出口夹角的取值,提供了上下限依据,大高压区的结构能有效降低液压力,为后续泵轴的设计提供理论依据和参考。 展开更多
关键词 齿轮泵 定量 静态 动态 液压力
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化探综合异常图定量编制方法及应用 预览
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作者 李欢 徐国志 +2 位作者 孙璐 李朋 邓宇飞 《地质通报》 CAS CSCD 北大核心 2019年第6期1062-1070,共9页
现阶段以单元素异常图为基础编制的综合异常图,只能定性地圈定出综合异常范围,并没有考虑异常点元素彼此之间的叠加贡献,不能定量评价综合异常。研究发现,该类图件不论在图面表达形式还是在应用效果中均存在诸多不足。明确了“平均衬度... 现阶段以单元素异常图为基础编制的综合异常图,只能定性地圈定出综合异常范围,并没有考虑异常点元素彼此之间的叠加贡献,不能定量评价综合异常。研究发现,该类图件不论在图面表达形式还是在应用效果中均存在诸多不足。明确了“平均衬度法”的概念,提出利用平均衬度法编制综合异常图的思路和方法,即以原始分析数据为基础,利用平均衬度定量表达综合异常范围,编制形成平均衬度综合异常图。对比结果表明,平均衬度法对综合异常的圈定效果优于累加衬度法和综合衬度法。平均衬度综合异常图特别适合1∶5万化探普查资料的开发研究,由于圈定的范围小、浓集中心明显,适合准确布置地表探矿工程,并可以节约勘查成本,提高找矿命中率。 展开更多
关键词 平均衬度综合异常图 定量 平均衬度法 浓集中心
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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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Fine-Mapping of qTGW1.2a, a Quantitative Trait Locus for 1000-Grain Weight in Rice 预览
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作者 WANG Wenhui WANG Linlin +2 位作者 ZHU Yujun FAN Yeyang ZHUANG Jieyun 《水稻科学:英文版》 CSCD 2019年第4期220-228,I0002-I0004,I0010,I0015共12页
Thousand-grain weight (TGW) is a key component of grain yield in rice. This study was conducted to validate and fine-map qTGW1.2a, a quantitative trait locus for grain weight and grain size previously located in a 933... Thousand-grain weight (TGW) is a key component of grain yield in rice. This study was conducted to validate and fine-map qTGW1.2a, a quantitative trait locus for grain weight and grain size previously located in a 933.6-kb region on the long arm of rice chromosome 1. Firstly, three residual heterozygotes (RHs) were selected from a BC2F11 population of the indica rice cross Zhenshan 97 (ZS97)///ZS97//ZS97/Milyang 46. The heterozygous segments in these RHs were arranged successively in physical positions, forming one set of sequential residual heterozygotes (SeqRHs). In each of the populations derived, non-recombinant homozygotes were identified to produce near isogenic lines (NILs) comprising the two homozygous genotypes. The NILs were tested for grain weight, grain length and grain width. QTL analyses for the three traits were performed. Then, the updated QTL location was followed for a new run of SeqRHs identification-NIL development-QTL mapping. Altogether, 11 NIL populations derived from four sets of SeqRHs were developed and used. qTGW1.2a was finally delimitated into a 77.5-kb region containing 13 annotated genes. In the six populations segregating this QTL, which were in four generations and were tested across four years, the allelic direction of qTGW1.2a remained consistent and the genetic effects were stable. For TGW, the additive effects ranged from 0.23 to 0.38 g and the proportions of phenotypic variance explained ranged from 26.15% to 41.65%. These results provide a good foundation for the cloning and functional analysis of qTGW1.2a. 展开更多
关键词 fine mapping GRAIN weight MINOR effect quantitative TRAIT LOCUS RICE GRAIN length GRAIN width
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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
DEVELOPMENT AND ASSESSMENT OF QUANTITATIVE PRECIPITATION ESTIMATION ALGORITHMS FOR S-,C-, AND X-BAND DUAL-POLARIZATION RADARS BASED ON DISDROMETER DATA FROM THREE REGIONS OF CHINA
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作者 张扬 刘黎平 +3 位作者 文浩 陈超 王晗 席宝珠 《热带气象学报:英文版》 SCIE 2019年第2期269-292,共24页
The accuracy of quantitative precipitation estimation(QPE) for dual-polarization radars can be improved by using a localized rainfall estimation algorithm derived from the raindrop size distribution(DSD). In the prese... The accuracy of quantitative precipitation estimation(QPE) for dual-polarization radars can be improved by using a localized rainfall estimation algorithm derived from the raindrop size distribution(DSD). In the present study,DSDs observed at Suzhou City, Jiangsu province;Yangjiang City, Guangdong province;and Naqu City, Tibet are analyzed during the rainy season together with the corresponding polarimetric variables for the above three regions.Most importantly, these DSD data are used to develop optimal 'synthetic' QPE algorithms for S-, C-, and X-band dual-polarization radars, which will be built or upgraded in the three regions. Meanwhile, a new piecewise fitting method(PFM) is proposed. It has been found that the number concentration N(D) of small raindrops(D<1 mm) is the highest in Suzhou, while that of larger raindrops(D>1 mm) is the highest in Yangjiang. The characteristics of the differential reflectivity(ZDR) and specific differential phase(KDP) are significantly different in the three locations,suggesting that different rainfall estimators are needed for different locations. Further performance assessment of the QPE based on DSD data indicates that the PFM QPE algorithm(LDSD) performs better than the conventional fitting method(CFM), and the localized QPE algorithm can improve the QPE accuracy. Observations from S-band dual-polarization radars and rain gauges in the Southern China Monsoon Rainfall Experiment are implemented to verify the performances of the QPE algorithms proposed in the present study. It is found that compared with non-localized algorithms, the localized LDSD algorithm yields the best results with at least 7.66% and 8.43% reductions in the RMSE and NE, respectively, which implies that while polarimetric variables can reflect DSD characteristics, the localized QPE algorithm remains necessary. 展开更多
关键词 atmospheric SOUNDING QUANTITATIVE PRECIPITATION estimation PIECEWISE fitting method drop size distribution localized QPE algorithm
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