检索结果-南通市图书馆

Comparison of the Levels of Five Heavy Metals in Human Urine and Sweat after Strenuous Exercise by ICP-MS

在线全文

学校读者我要写书评

暂无评论

Journal of Applied Mathematics and Physics 2016年第2期4卷 183-188页

作者： shengxiang tang Xinzhe Yu Cinan Wu College of Life Science Guizhou University Guiyang China College of Pharmaceutical Science Guizhou University Guiyang China Zunyi Normal College Zunyi China

Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure the levels of trace heavy metals in human urine and sweat, to compare the performance of ICP-MS using three sample processing methods, namely direct dilution, wet digestion, and microwave digestion. The results showed that the wet digestion ICP-MS method has the highest accuracy (relative standard deviation ≤10%) and is more useful for measuring the levels of trace heavy metals in urine and sweat. Hence, we used this method to compare the levels of the five trace heavy metals, namely chromium, copper, zinc, cadmium, and lead, in the urine and sweat of adults after strenuous exercise. The results showed that the levels of these five trace heavy metals in sweat were significantly higher than those in urine after strenuous exercise (The differences between the measurements in urine and those in sweat were significant P ≤ 0.01). The results suggested that exercise-induced sweating can effectively remove the harmful heavy metals from the human body.

关键词： Strenuous Exercise Urine Sweat ICP-MS Heavy Metals

Genetic diversity of rice cultivars (Oryza sativa L.) in China and the temporal trends in recent fifty years

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2006年第6期51卷 681-688页

作者： QI Yonawen ZHANG Dongling ZHANG Hongliang WANG Meixing SUN Junli WEI Xinghua QIU Zongen tang shengxiang CAO Yongsheng WANG Xiangkun LI Zichao Key Laboratory of Crop Genomics and Genetic Improvement of Min- istry of Agriculture and Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University Beijing 100094 China China National Rice Research Institute Hangzhou 310006 China Institute of Crop Science Chinese Academy of Agricultural ScienceBeijing 100081 China

To understand geographical distribution of the genetic diversity of rice cultivars {Oryza sativa L.) and its trends in recent fifty years in China, 453 ’ accessions were analyzed by 36 microsatellites loci and 42 phenotypic traits. Results revealed that the genetic diversity by SSRs is highly consistent with that by phenotypic traits and the genetic diversity of indica cultivars was higher than that of japonica cultivars; the genetic diversity of cultivars declined from 1950s to 1980s and then increased greatly; among the six rice ecological zones (REZs), genetic diversity of REZTl was the highest and those of REZV and REZVT were the lowest at both DNA and phenotypic level. Jiangsu and Jiangxi provinces in the middle and lower reaches of Yangtze River and Sichuan province in southwest of China were the areas with the highest genetic diversity. Breeders in REZV which is an important japonica rice area but with very low genetic diversity should explore more gene resources to widen the genetic backgrounds of cultivars.

关键词：中国水稻种植遗传多样性微卫星标记表型

Genetic structure and diversity of Oryza sativa L. in Guizhou,China

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2007年第3期52卷 343-351页

作者： ZHANG DongLing ZHANG HongLiang WEI XingHua QI YongWen WANG Meixing SUN JunLi DING Li tang shengxiang QIU Zong'En CAO YongSheng WANG XiangKun LI ZiChao Key Laboratory of Crop Genomics and Genetic Improvement of Ministry of Agriculture Key Laboratory of Crop Heterosis and Utilizition of Ministry of Education and Beijing Laboratory of Crop Genetic Improvement China Agricultural University Beijing 100094 China China National Rice Research Institute Hangzhou 310006 China Institute of Crop Science Chinese Academy of Agricuiturel Science Beijing 100081 China

Preserving many kinds of rice resources and rich variations, Guizhou Province is one of the districts with the highest genetic diversity of cultivated rice (Oryza sativa L.) in China. In the current research, genetic diversity and structure of 537 accessions of cultivated rice from Guizhou were studied using 36 microsatellite markers and 39 phenotypic characters. The results showed that the model-based genetic structure was the same as genetic-distance-based one using SSRs but somewhat different from the documented classification (mainly based on phenotype) of two subspecies. The accessions being classified into indica by phenotype but japonica by genetic structure were much more than that being classified into japonica by phenotype but indica by genetic structure. Like Ding Ying’s taxonomic sys- tem of cultivated rice, the subspecific differentiation was the most distinct differentiation within culti- vated rice. But the differentiation within indica or japonica population was different: japonica presented clearer differentiation between soil-watery ecotypes than indica, and indica presented clearer differen- tiation between seasonal ecotypes than japonica. Cultivated rices in Guizhou revealed high genetic diversity at both DNA and phenotypic levels. Possessing the highest genetic diversity and all the nec- essary conditions as a center of genetic diversity, region Southwestern of Guizhou was suggested as the center of genetic diversity of O. sativa L. from Guizhou.

关键词：贵州水稻遗传结构遗传多态性表型特征

Interspecific hybrid plants obtained from cultivars (AA) crossed with wild Oryza species (CC)

在线全文

学校读者我要写书评

暂无评论

Chinese Rice Research Newsletter 1994年第3期2卷 2-3页

作者： tang shengxiang YAN Huihuang Hu Huiying CNRRI,310006 Hangzhou,China

Wild rice ***(CNW 258,CNW 259)***(CNW 260,CNW 261)have CCgenome and high resistance to brown planthopper(BPH)and whitebacked planthopper(WBPH).Totransfer the resistant gene(s)of the wild rice intoAsian cultivated rice... 详细信息

关键词： AA BPH crossed with wild Oryza species CC

同方期刊数据库

AMMI analysis of interaction of genotype and environment in chalkiness of indica rice

在线全文

学校读者我要写书评

暂无评论

Chinese Rice Research Newsletter 1997年第1期5卷 1-2页

作者： tang shengxiang JIANG Yunzhu YU Hangyong WANG Lei CNRRI,Hangzhou 310006,China

Chalkiness is an unpleasant trait for rice con-sumer,which is known to be controlled geneti-cally and affected by environment during *** used the model of Additive Main

关键词： AMMI analysis of interaction of genotype and environment in chalkiness of indica rice CD

同方期刊数据库

在线全文

学校读者我要写书评

暂无评论

对INGER水稻种质的遗传评价和利用

植物遗传资源科学 2002年第2期3卷 46-50页

作者：汤圣祥余汉勇中国水稻研究所杭州310006

中国自1981年起参加了国际水稻遗传评价(INGER)的合作研究。20年来已引入 INGER 提供的1.8万余份各国水稻种质,经全国14点的多年综合评价,从中直接命名推广了35个品种,作恢复系(源)组配了28个杂交水稻新组合,筛选出一大批高产、优质、... 详细信息

中国自1981年起参加了国际水稻遗传评价(INGER)的合作研究。20年来已引入 INGER 提供的1.8万余份各国水稻种质,经全国14点的多年综合评价,从中直接命名推广了35个品种,作恢复系(源)组配了28个杂交水稻新组合,筛选出一大批高产、优质、多抗、耐逆、广亲和等材料,并作为亲本利用于全国各育种项目。据不完全统计,INGER 种质在中国的种植面积累计约1450万 hm^2,增产稻谷544万 t,取得了巨大的经济效益和社会效益。遗传背景多样化的 INGER 水稻种质不仅提高了我国的水稻育种水平,而且丰富了我国的稻种资源宝库。

关键词： INGER 水稻种质遗传评价利用引种

基于AHP与模糊集值统计法的直升机选型研究

在线全文

学校读者我要写书评

暂无评论

中国民航飞行学院学报 2022年第2期33卷 22-25页

作者：钱宇唐盛香中国民用航空飞行学院四川广汉618307

使用层次分析法建立了选型指标的层次结构模型,对层次结构模型中每一层选型指标做成对比较得到了判断矩阵,计算出权重值,利用模糊集值统计法对专家打分进行处理得出了选型指标特征值,与权重值相乘求和即机型总评分。利用救护直升机选型... 详细信息

使用层次分析法建立了选型指标的层次结构模型,对层次结构模型中每一层选型指标做成对比较得到了判断矩阵,计算出权重值,利用模糊集值统计法对专家打分进行处理得出了选型指标特征值,与权重值相乘求和即机型总评分。利用救护直升机选型进行了实例分析,得到直-15直升机更能满足要求的结论。

关键词：模糊集值统计法 AHP 直升机选型

基于SVR-随机森林模型的民机落地剩油预测研究

在线全文

学校读者我要写书评

暂无评论

中国民航飞行学院学报 2023年第4期34卷 40-43页

作者：林熙颢韦冬冬唐盛香钱宇上海飞机客户服务有限公司上海201100 中国民用航空飞行学院四川广汉618307

针对国产民机落地剩油的预测与单一算法预测精度较低的问题,本文提出了一种基于支持向量回归机(SVR)与随机森林(RF)算法组合的预测模型对国产民机落地剩油做预测。灰色关联度分析得到落地剩油关联度较高的因素,简化模型输入量;采用单一... 详细信息

针对国产民机落地剩油的预测与单一算法预测精度较低的问题,本文提出了一种基于支持向量回归机(SVR)与随机森林(RF)算法组合的预测模型对国产民机落地剩油做预测。灰色关联度分析得到落地剩油关联度较高的因素,简化模型输入量;采用单一的SVR算法与RF算法进行落地剩油预测,利用倒数误差法将两个单一算法组合起来对落地剩油做预测。实例验证,单一的预测模型准确率为81.21%、83.91%;组合模型的准确率为93.2%,提高了落地剩油预测的精度,有利于飞机在安全飞行的前提下合理减少额外油,提高经济效益。

关键词：落地剩油 SVR 随机森林倒数误差法组合预测

同方期刊数据库

基于VSG的永磁直驱风电机组惯量支撑控制策略

在线全文

学校读者我要写书评

暂无评论

电网与清洁能源 2020年第12期36卷 115-120页

作者：马磊刘国荣毛云坤唐圣翔肖吉湖南工程学院风电装备与电能变换协同创新中心湖南湘潭411104

风电并网容量比重不断加大,减弱了系统的调频能力与惯量支撑能力,电网失稳日益严重。针对这些问题提出了基于虚拟同步机(VSG)的永磁直驱风电机组的控制方案。模仿同步机的功频控制特点,使系统具有惯量响应能力。风电机组经PWM变流器并网... 详细信息

风电并网容量比重不断加大,减弱了系统的调频能力与惯量支撑能力,电网失稳日益严重。针对这些问题提出了基于虚拟同步机(VSG)的永磁直驱风电机组的控制方案。模仿同步机的功频控制特点,使系统具有惯量响应能力。风电机组经PWM变流器并网,在机侧变流器利用直流电压外环和电流内环控制,维持直流母线电压稳定,VSG从网侧变流器接入,通过设计有功频率和无功电压控制方案,对系统进行调频、调压。使用Matlab软件搭建模型,调整仿真参数,仿真结果表明,该控制方案使系统可以模拟同步发电机的惯量响应特性,能够有效地解决由于风速或者电网负荷改变引起的频率震荡问题。

关键词：永磁直驱风电机组虚拟同步机调频调压惯量响应