检索结果-南通市图书馆

Heterosis and combining ability evaluation for growth traits of blunt snout bream(Megalobrama amblycephala)when crossbreeding three strains

引用

Chinese Science Bulletin 2014年第9期59卷 857-864页

作者： Wei Luo Cong Zeng Shaokui Yi Nicholas Robinson Weimin Wang Zexia Gao College of Fisheries Key Laboratory of Agricultural Animal Genetics Breeding and Reproduction of Ministry of Education/Key Laboratory of Freshwater Animal Breeding Ministry of Agriculture Huazhong Agricultural University Nofima PO Box 5010 1432 s Norway Collaborative Innovation center for Healthy Freshwater Aquaculture of Hubei Province

The blunt snout bream(Megalobrama amblycephala)is a major aquaculture species in the Chinese freshwater polyculture *** this study,complete diallel crossing of three strains(i.e.,Liangzi[LZ],Poyang[PY]and Yuni[YN])was used to evaluate the combining ability and heterosis effect of intraspecific crossbreeding on the growth performance(i.e.,body weight,total length,body length,body height,and Fulton’s coefficient of condition).The offspring produced from the three strains were reared in a communal pond for 20 months,and nine microsatellites were used to assess their *** the749 offspring,708(94.53%)could be assigned directly to a single parental *** differences were observed in body weight(BW)among the different combinations,indicating that the combining ability of BW from each strain was significantly *** general combining ability(GCA)of BW from the sire was much higher than that from the *** GCA for the dam and sire of the LZ and YN were the largest and the smallest,*** special combining ability of YN$9 PY#was the largest,and YN$9 PY#showed significantly positive heterosis effects on all F1growth traits,except for Fulton’s condition coefficient(K)(P\0.05).In addition,significant positive linear correlations were found between the mean BW of corresponding progeny and the H E of the parental generation(y=600.7x-29.472,r=0.8651,P=0.0026),H O(y=1206.9x-518.14,r=0.7436,P=0.0216),and the polymorphism information content(y=1021.3x-331.31,r=0.8245,P=0.0063)as determined by a correlative *** findings obtained from the study will be important for future considerations of *** stock improvement programs.

关键词：杂种优势效应特殊配合力生长性状双列杂交团头鲂平均体重评价线性相关关系

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

地面堆载作用下黏弹性地层盾构施工诱发土体响应时域解

引用

岩土工程学报 2021年第1期43卷 34-42页

作者：张治国张洋彬张成平王志伟 PAN Y T 上海理工大学环境与建筑学院上海200093 中国铁道科学研究院高速铁路轨道技术国家重点实验室北京100081 北京交通大学城市地下工程教育部重点实验室北京100044 Department of Civil and Environmental engineering National University of SingaporeSingapore119077

目前针对软土地层盾构施工诱发周围土体变形影响的研究一般是基于瞬时开挖工况,较少考虑黏弹性土体的流变特性,也较少考虑地表堆载给盾构隧道施工所带来的影响。从地基黏弹性角度出发,引入隧道洞周的椭圆化收敛变形模式,采用复变函数理... 详细信息

目前针对软土地层盾构施工诱发周围土体变形影响的研究一般是基于瞬时开挖工况,较少考虑黏弹性土体的流变特性,也较少考虑地表堆载给盾构隧道施工所带来的影响。从地基黏弹性角度出发,引入隧道洞周的椭圆化收敛变形模式,采用复变函数理论并运用Laplace变换技术,提出了地表堆载作用下盾构隧道开挖引起的周围土体位移和应力的时域解。依托相关工程监测数据与简化时域解对比,得到了较好的一致性。研究结果表明:所得出的时域解能较好地反映地表堆载作用下盾构隧道开挖对周围土体位移场的影响,以及地层变形随时间的发展趋势。在地表堆载影响下,随着时间推移,开挖引起的地层变形不断增加,沉降速率则呈现出逐渐衰弱直至为零规律,而堆载突变导致其地表沉降值尤其沉降速率变化显著。研究成果对黏性地层密集堆载群范围内的隧道施工控制具有一定理论指导意义。

关键词：盾构隧道地表堆载黏弹性椭圆化收敛变形时域解

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Technical Design and Implementation of Cross-Platform Industrial Product Order System

引用

Journal of Cyber Security 2021年第1期3卷 1-10页

作者： Yu Xue Xu Cai Shoubao Su Junxiang Han Romany F.Mansour School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China Jiangsu Key Laboratory of Data Science and Smart Software Jinling Institute of TechnologyNanjing211169China Department of Mathematics Faculty of ScienceNew Valley UniversityEl-Kharja7251Egypt

According to some data in the Industrial Purchasing Trends report released by China in 2017,we can see that e-commerce purchasing channels have ranked first among all industrial products purchasing channels in China compared with European and American *** addition,in the whole industrial product purchasing market,we can also see that both manufacturers and suppliers are making active e-commerce transformation,and some other Internet giants are also actively entering the industrial product e-commerce *** at present,the revenue of all kinds of subjects is still a lot of room for improvement compared to the United States industrial *** the domestic e-commerce market of industrial products has a variety of problems,also contains huge opportunities and development *** mobile Internet technology is becoming more and more *** is particularly important to develop a cross-platform industrial product order system that supports the collaborative work and unified experience of Android,iOS,and *** system uses a uni-app framework to develop front-end applications,which can realize an order management system with code running across multiple *** back end is built based on LNMP *** is the most popular free operating *** is a free and efficient web server with good stable performance,rich functions,simple operation and maintenance,fast processing of static files,and minimal system resource *** database is one of the most widely used relational databases in Web application data *** server side is written by PHP script under ThinkPHP framework,which is quick,open-source,and cross-platform in system *** these four kinds of software are free,open-source software,together,they can become a free,efficient,highly extensible website service system.

关键词： Order management system cross-platform LNMP architecture uniapp framework ThinkPHP framework

来源：

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

Factors Analysis of Affecting Loading and Reinforcing Scheme of Large Goods in railway

引用

World Journal of engineering and technology 2016年第3期4卷 60-68页

作者： Xiaohong Li School of Traffic and Transportation Beijing Jiaotong University Beijing China center of Cooperative Innovation for Beijing Metropolitan Transportation Beijing China

Large goods transported in railway are kinds of special goods and they are very important in national construction. In order to transport safely, loading and reinforcing schemes must be made first. How to design a reasonable scheme will be affected by many factors. This paper presents the characteristic of the large goods, summarizes the process of designing a loading and reinforcing scheme of large good, then probes the factors of affecting the loading and reinforcing scheme and gives a detail analysis. It’s considered that those out-of-gauge and overweight degree of goods, center-of- gravity height of a loaded wagon, position of center-of-gravity of goods, type of wagon for using, reinforcement material and reinforcement method, transport expense and transport organization could affect a scheme in the aspects of safety, economy, rapidity and convenience. This conclusion will instruct and help to make a good scheme.

关键词： Loading and Reinforcing Scheme Out-of-Gauge Goods Overweight Goods Rail Freight Transportation Effecting Factor

来源：

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

Dune dynamics in the southern edge of Dunhuang Oasis and implications for the oasis protection

引用

Journal of Mountain Science 2018年第10期15卷 2172-2181页

作者： AN Zhi-shan ZHANG Ke-cun TAN Li-hai ZHANG Hu NIU Bai-cheng Dunhuang Gobi and Desert research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Key Laboratory of Desert and Desertification Chinese Academy of SciencesLanzhou 730000China Academy of Water Resource Conservation Forests of Qilian Mountains in Gansu Province Test Station of Deserification Control in HongshawoZhangye 734000China

The survival of Dunhuang Oasis is largely determined by the evolution of sand dunes in the southern edge of the oasis, mainly composed of shield dunes and mega pyramid dunes, which occupy twothirds and one-third of the area, respectively. However, few studies have focused on dynamics of these dunes, especially in terms of quantification. So the theoretical basis of sand-control engineering is relatively limited. Here we present the characteristics of dune dynamics of a shield dune and mega pyramid dune in the southern edge of Dunhuang Oasis during April 2014-April 2016 based on measurement data of a 3-D laser scanner. Results indicate that the volume of the shield dune decreased during the monitoring period of two years, and the gravity centers of the monitored shield dune moved windward, indicating that sand was transported toward the oasis. Conversely, the dune volume of the mega pyramid dune increased and the gravity center presented no prominent movement, indicating that the megapyramid dune was relatively stable and its migration toward the oasis was not notable. Thus, compared with mega pyramid dunes, shield dunes in the southern edge of Dunhuang Oasis are identified as a more significant sand source endangering the protection of the oasis, and sand-control engineering should mainly focus on these shield dunes.

关键词：金字塔沙丘绿洲保护动力学控制工程激光扫描仪测量数据相对稳定 3-D

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Immersive Learning for Sustainable Building Design and construction Practices

引用

Journal of Civil engineering and Architecture 2017年第9期11卷 841-852页

作者： Tahar Messadi Winifred E. Newman Andrew Braham Darin Nutter 21st Century Chair of Sustainability University of Arkansas Fayetteville AR 72701 USA Department of Architecture University of Arkansas Fayetteville AR 72701 USA Department of Civil engineering University of Arkansas Fayetteville AR 72701 USA Department of Mechanical engineering University of Arkansas Fayetteville AR 72701 USA

来源：

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

Essential aroma substances and release pattern of Xinhui Chenpi

引用

Beverage Plant research 2022年第1期2卷 177-184页

作者： Doudou Yang Xuejiao Wu Heyun Shi Jun Zhang Chao Wang College of Food Science and Biological engineering Tianjin Agricultural UniversityNo.22Jinjing RoadTianjin 300384PR China Key Laboratory of Tea Science of Ministry of Education Hunan Agricultural UniversityChangshaHunan 410128PR China

This study focuses on analyzing aqueous solutions of aroma-active compounds in Xinhui Chenpi distilled after being heated with headspace solid-phase microextraction and gas chromatography-mass spectrometry(HS-SPME-GC/MS).Feasibility of this method was also tested by comparison with crushed *** study also analyzed the aqueous solutions of the aroma-active compounds employing gas chromatography-olfactometry(GC-O)defense,aroma extraction dilution analysis(AEDA)and odor activity value(OAV)as well as their emission *** to the study,there are 24 major aroma-active detected in the aqueous ***,d-limonene,2-methoxy-4-vinylphenol,andα-terpineol with sweet,spicy,and woody aroma contributed the most to the aroma-active compounds and were considered to be the essential aroma substances of *** heated,the aroma of aromatic-active compounds rich in Chenpi volatilized rapidly and the release dropped dramatically in a short *** substantial aroma-active compounds can be collected from the first ten released segments.

关键词： solution release heated

来源：

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

Study on the Relationship between Utilization Ratios and Conversion Rates of Nitrogen,Phosphorus and Potassium for Rice

引用

Meteorological and Environmental research 2020年第5期11卷 25-32页

作者： Shuojin WANG Zhiping HUANG Changhong MI Hongyan ZHENG Jian DING Shutian LIU Xianda HOU Ling LU Yanlin HOU Guangxi Geographical Indication Crops research center of Big Data Mining and Experimental engineering technology Nanning Normal UniversityNanning 530001China Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation Nanning Normal UniversityNanning 530001China Key Laboratory of Environment Change and Resources Use in Beibu Gulf(Nanning Normal University) Nanning 530001China Agro-Environmental Protection Institute Ministry of Agriculture and Rural AffairsTianjin 300191China

This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since *** results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of rice for plot was that,Y N≈a+b×optimum yield+c×optimum fertilizer amount of K,Y P≈a+b×optimum yield,Y K≈a respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships:①no significant relationships:25,of which 14 were soil nutrients and 9 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient yield ratio and fertilizer utilization ratio;②consistent significant relationships:2,one was that yield ratio and utilization ratio of N were positively correlated with the optimum production,explaining the importance of N for production,the other was that yield ratio and utilization ratio of P had a significantly positive correlation with conversion rate and utilization ratio of N,illustrating that nitrogen and phosphorus had mutual promotion;③contrary significant relationships:5,these showed as negative correlations of fertilizer utilization ratio and positive correlation of nutrient conversion ratio;④complementary significant relationships:22,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the index of fertilizer efficiency in one season,while the nutrient conversion rate was the index of fertilizer efficiency in more seasons,which showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated.

关键词： Optimum yield Optimum fertilization amount Nutrient conversion rate Fertilizer utilization ratio Relative abundance-deficiency value of soil nutrient

来源：

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

Summary on the Index System of Ecological Balanced Fertilization for Maize

引用

Meteorological and Environmental research 2020年第5期11卷 55-61页

作者： Hongyan ZHENG Shutian LIU Xianda HOU Shuojin WANG Zhiping HUANG Jian DING Changhong MI Ling LU Yanlin HOU Agro-Environmental Protection Institute Ministry of Agriculture and Rural AffairsTianjin 300191China Guangxi Geographical Indication Crops research center of Big Data Mining and Experimental engineering technology Nanning Normal UniversityNanning 530001China Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation Nanning Normal UniversityNanning 530001China Key Laboratory of Environment Change and Resources Use in Beibu Gulf(Nanning Normal University) Nanning 530001China

This paper studied the index system of ecological balanced fertilization for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since *** results and conclusions were as follows:①the optimum N,P and K fertilization amounts of maize were within the normal range,and the application of this standard could not cause obvious non-point source pollution.②The conversion rates of N,P and K of maize were respectively higher than their respective utilization ratios under the optimum fertilization amount.③At present,the soil N for maize was in an absence state,and soil P and K were in a state of not obvious lack.④Optimum N,P and K fertilization amounts were significantly negatively correlated with their respective conversion ratios,respectively,and it provided a quantitative scientific basis for calculating the optimum fertilization amount according to the nutrient conversion *** province can use this significant relationship to guide the determination of the average optimal fertilization amounts of N,P and K and the optimal production in the province.⑤The research results of nutrient conversion rate showed that any excessive application of N,P and K would reduce their own nutrient conversion rates,and may also reduce the conversion rates of other *** characteristics of crops absorbing N,P and K proportionally required that soil nutrients must be balanced in order to obtain high production,and fertilization was only the main means to regulate soil nutrient balance.

关键词： Optimum yield Optimum fertilization amount Nutrient conversion rate Fertilizer utilization ratio Relative abundance-deficiency value of soil nutrient

来源：

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

Comparison of the Index System of Ecological Balanced Fertilization for Three Crops

引用

Meteorological and Environmental research 2020年第5期11卷 76-90页

作者： Xianda HOU Hongyan ZHENG Shuojin WANG Shutian LIU Zhiping HUANG Jian DING Changhong MI Ling LU Yanlin HOU Guangxi Geographical Indication Crops research center of Big Data Mining and Experimental engineering technology Nanning Normal UniversityNanning 530001China Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation Nanning Normal UniversityNanning 530001China Key Laboratory of Environment Change and Resources Use in Beibu Gulf(Nanning Normal University) Nanning 530001China Agro-Environmental Protection Institute Ministry of Agriculture and Rural AffairsTianjin 300191China

This paper conducted comparative study of the index system of ecological balanced fertilization for rice,wheat and maize by data mining method based on data of"3414 fertilizer field trials"of rice,wheat and maize by published papers from national soil testing and recommendation since *** main conclusions of this paper were as follow:①since the three crops all belonged to Gramineae,they were consistent in variation trends of fertilizer utilization ratio,nutrient conversion rate,relative abundance-deficiency value of soil nutrient,optimum fertilization amount in most cases.②Due to the influence of the economic production,biological production,different water conditions in paddy field and dry farmland,length of growing season,cropping system(one year before and after the rotation)and so on,sometimes the laws of four aspects above mentioned for the three crops had opposite and gradient variations.

关键词： Optimum yield Optimum fertilization amount Nutrient conversion rate Fertilizer utilization ratio Relative abundance-deficiency value of soil nutrient

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：