科技文献中引文的功能应用和检索方法

随着科技和互联网技术的发展，人们可以获得的科技文献越来越多，读者要在文献信息海洋里获取特定的文献，就必须正确选择检索工具、应用科学的检索方法。通过对引用的参考文献检索，将全文文献与引用的参考文献链接起来，实现基于参考文献的源文献查找，实现文献所述知识点的追根溯源，提高获取知识的效率。     

1998～2000年《农业工程学报》检索指标

《中国科技期刊引证报告》( CJCR)及其本刊检索数据《中国科技期刊引证报告》( CJCR)是由中国科技信息研究所 ,选择多种期刊评价指标 ,以一定的中国科技论文统计源期刊 ( 2 0 0 0年为 1 40 6种期刊 )引用的数据为依据 ,对科技期刊论文进行统计分析 ,进而按照客观数据对期刊进行评价排序。该报告每年一版 ,为中国广大科技工作者 ,期刊编辑部和科研管理部门科学评价期刊 ,客观准确地选择和利用期刊提供了权威参考依据。统计数据表明 (见表 1 ) ,本刊最近 3年的影响在逐步扩大。统计数据表明 :本刊在农业工程类期刊中位居榜首 ,与农业类名…     

互联网上农业外文资源的利用

本文列举了互联网上关于农业外文资源的部分网站，简述了通过搜索引擎、浏览期刊主页、访问专业数据库网站、大型联机检索系统、专业图书馆、标准、专利等方式检索科技文献，介绍了检索的常见功能，对科技人员进行科技文献检索有一定借鉴意义。     

水土保持学术期刊在中国论文统计中的现状和地位

科技论文是一个国家科技水平的反映,该文以详实的资料论述了中国科技论文在国际《ＳＣＩ》《ＥＩ》《ＩＳＴＰ》三大检索工具中的地位;水土保持学术期刊在《中国科学引文索引》中的地位,并提出吸收国内水土保持科学优秀论文的有益建议。     

水土保持文献的特点及其国内检索途径

水土保持文献的特点及其国内检索途径刘梅（中国科学院西北水土保持研究所陕西杨陵藏７１２１００）（水利部西北水土保持研究所陕西杨陵藏７１２１００）科技文献的检索与利用是科技人员的基本功。目前，科学技术在迅速发展，人们的情报意识在日益增强，每一个科技人员都...     

欢迎订阅2015年《中国生态农业学报》

《中国生态农业学报》为月刊,中国科学院主管,中国科学院遗传与发育生物学研究所和中国生态经济学会主办,科学出版社出版。《中国生态农业学报》为中国期刊方阵双效期刊、中国科技核心期刊、中文核心期刊、中国精品科技期刊、RCCSE 中国权威学术期刊,系中国学术期刊综合评价数据库、中国期刊全文数据库、中国学术期刊文摘、中国科学引文数据库、中国科技论文与引文数据库、CNKI中国期刊全文数据库源刊,并被国际农业生物学文摘(CABI)、美国化学文摘(CA)、哥白尼索引(IC)、美国乌利希国际期刊指南等国际数据库及检索单位收录。据《中国科技期刊引证报告(核心版)》(2013年版)2012年影响因子为1.068,农学类期刊排名第4,1994种期刊总排名第110。     

国内农业气象文献的检索方法

<正> 随着科学技术在深度和广度上的不断发展,科技文献的数量也在急剧的增加。因此,为了正确迅速地查到需要的各种农业气象文献,就必须掌握一套科学的检索方法,才能达到事半功倍的效果。1.检索国内农业气象文献的几个特点首先要了解我国农业气象工作的特点农业气象科学是一门界于农业科学和气象科学之间的边缘科学,它又与地理学、生态学、森林学、生物学、水文学等多种学科有着不同程度的联系。因而,我国研究农业气象学的科学家不但分散在各个部门、各个学     

《中国生态农业学报》征稿、征订启事

正《中国生态农业学报》原名《生态农业研究》,1993年创刊,中国科学院遗传与发育生物学研究所和中国生态经济学会主办,科学出版社出版。系中文核心期刊、中国期刊方阵双效期刊、中国科技核心期刊、中国精品科技期刊,中国科技论文统计源刊、万方数据库统计源刊、中国科学引文数据库源刊、中国期刊网统计源刊以及中国期刊全文数据库源刊,并被国际农业生物学文摘(CABI)、美国化学文摘(CA)、哥白尼索引(IC)、美国乌利希国际期刊指南等国际数据库及检索单     

网络信息资源搜索引擎利用的方法与技巧

掌握网络信息资源的检索方法是我们获取信息的重要途径之一。目录检索、关键词检索和多元检索是网络信息资源检索的三种方法。一些常用的检索技巧也可提高人们的检索效率。     

基于卷积神经网络和重排序的农业遥感图像检索

卷积神经网络具有很强的分类能力,并在图像分类等应用中取得显著成效,但遥感图像检索应用中还较少利用该分类能力。为了提高农业遥感图像检索性能,该文提出一种利用卷积神经网络分类能力的遥感图像检索方法。首先利用微调的卷积神经网络模型提取查询图像的检索特征和估计查询图像的每个类别权重,然后利用根据CNN模型判断的检索图像类别和初始排序结果计算类别查准率,根据查询图像的类别权重和类别查准率计算加权类别查准率,最后根据加权类别查准率对图像类别进行排序,并根据排序结果对初始检索结果进行重排序,从而得到最终的检索结果。试验结果表明:该检索方法在PatternNet数据集中平均查准率达到97.56%,平均归一化调整后的检索秩达到0.0201;在UCM_LandUse数据集中平均查准率达到93.67%,平均归一化调整后的检索秩达到0.049 2,较之其他遥感图像检索方法下降0.2358,降幅超过82.7%;平均每张检索图像重排序时间大约是初始排序时间的1%。该文提出的重排序方法可以得到更好的遥感图像检索结果,提高了遥感图像检索性能,将有助于农业信息领域信息化和智能化。     

基于ArcGIS Engine的土地变更调查管理系统设计与实现

自动化、科学化和现代化管理是土地变更调查发展的必然趋势。该文根据土地变更调查的特点，设计了基于ArcGIS Engine的土地变更调查管理系统，实现变更数据不同时期、不同数据源的叠加分析，并自动输出报表。研究结果表明系统具有较强的针对性，也具有较大的实用价值。设计的土地变更调查管理系统能够保证变更前后的各地类总面积不变，同时能够根据调查的变更数据分析出地类发生变化的流向，从而生成各种统计报表。     

Organization of the Delivery of Scientific,Technical, and Economic Information to the Sector of Agriculture in the Slovak Republic

The hub of agricultural production and education, and the center of scientific and technological information dissemination relevant to Slovak agriculture is Nitra, located in the southwestern part of Slovakia. Preeminent among the libraries of the agricultural sector is the Slovak Agricultural Library in Nitra, which serves as the branch library of Ùvtiz in Prague and as the library for the University of Agriculture. In addition to providing traditional library and information services, library staff also provide analystical reports used for forecasting and policy development by the Ministry of Agriculture and Nutrition.     

Market Research Reports: An Overlooked Resource for Agribusiness Libraries

ABSTRACT

In today's competitive agribusiness climate, agribusiness professionals, and students perform research to develop new products for the marketplace. While traditional search tools such as AGRICOLA and CAB Abstracts are important for research, the content in those databases is mostly scientific in nature. Market research reports are an excellent resource for understanding the marketplace and for aiding researchers in new product development. This article defines and explains the purpose of market research and, by using a case study of an agribusiness course at a research university, compares the content from four market research products.     

Photodegradation of Tri(Chloropropyl) Phosphate Solution by UV/O3

The prediction of the time and the efficiency of the remediation of contaminated soils using soil vapor extraction remain a difficult challenge to the scientific community and consultants. This work reports the development of multiple linear regression and artificial neural network models to predict the remediation time and efficiency of soil vapor extractions performed in soils contaminated separately with benzene, toluene, ethylbenzene, xylene, trichloroethylene, and perchloroethylene. The results demonstrated that the artificial neural network approach presents better performances when compared with multiple linear regression models. The artificial neural network model allowed an accurate prediction of remediation time and efficiency based on only soil and pollutants characteristics, and consequently allowing a simple and quick previous evaluation of the process viability.     

Identification and characterization of low molecular weight polyphenols in berry leaf extracts by HPLC-DAD and LC-ESI/MS

This paper reports the results of qualitative and quantitative analyses of low molecular weight phenolics from five berry leaf extract using HPLC-DAD and LC-ESI/MS. The identification of the black currant, raspberry, bilberry, honeysuckle, and strawberry leaf phytochemicals was based on the comparison of UV-vis absorption maxima (λ(max)) and mass spectral analysis. The peak identification in samples was also based on comparisons of the retention times (t(R)) of the isolated phytochemical standards. Knowledge of the precise phenolic profile of berry leaves may offer a scientific basis to put the underutilized berry leaves to good use as very cheap raw materials for polyphenol extract production. These studies indicated that these leaves can be used as a good and cheap source of bioactive constituents. These results suggest that berry leaves are a potential source of phenolics and have potential pro-healthy properties to contribute to human health.     

Environmental fate and effects of Bacillus thuringiensis (Bt) proteins from transgenic crops: a review

This paper reviews the scientific literature addressing the environmental fate and nontarget effects of the Cry protein toxins from Bacillus thuringiensis (Bt), specifically resulting from their expression in transgenic crops. Published literature on analytical methodologies for the detection and quantification of the Cry proteins in environmental matrices is also reviewed, with discussion of the adequacy of the techniques for determining the persistence and mobility of the Bt proteins. In general, assessment of the nontarget effects of Bt protein toxins indicates that there is a low level of hazard to most groups of nontarget organisms, although some investigations are of limited ecological relevance. Some published reports on the persistence of the proteins in soil show short half-lives, whereas others show low-level residues lasting for many months. Improvements in analytical methods will allow a more complete understanding of the fate and significance of Bt proteins in the environment.     

纳米TiO2光半导体材料防治植物病害的初步研究

纳米TiO₂光半导体材料是一种具有抗菌与环境净化功能的新型环境友好材料，试验首次探索了将其应用于植物病害防治的可能性。在黄瓜霜霉病防治研究的栽培试验中发现，喷施纳米TiO₂光半导体溶胶材料可以显著地降低黄瓜霜霉病的发病率和病情指数，减少叶片病斑数量与病斑面积。试验研究结果初步证实了其对黄瓜霜霉病害具有一定的防治作用，为以纳米TiO₂光半导体溶胶材料为主要有效成分的植物抗菌剂与保护剂的开发提供了参考依据。     

A review of the effectiveness of agriculture interventions in improving nutrition outcomes

OBJECTIVES: To review the impact of agriculture interventions on nutritional status in participating households, and to analyse the characteristics of interventions that improved nutrition outcomes. DESIGN: We identified and reviewed reports describing 30 agriculture interventions that measured impact on nutritional status. The interventions reviewed included home gardening, livestock, mixed garden and livestock, cash cropping, and irrigation. We examined the reports for the scientific quality of the research design and treatment of the data. We also assessed whether the projects invested in five types of 'capital' (physical, natural, financial, human and social) as defined in the Sustainable Livelihoods Framework, a conceptual map of major factors that affect people's livelihoods. RESULTS: Most agriculture interventions increased food production, but did not necessarily improve nutrition or health within participating households. Nutrition was improved in 11 of 13 home gardening interventions, and in 11 of 17 other types of intervention. Of the 19 interventions that had a positive effect on nutrition, 14 of them invested in four or five types of capital in addition to the agriculture intervention. Of the nine interventions that had a negative or no effect on nutrition, only one invested in four or five types of capital. CONCLUSIONS: Those agriculture interventions that invested broadly in different types of capital were more likely to improve nutrition outcomes. Those projects which invested in human capital (especially nutrition education and consideration of gender issues), and other types of capital, had a greater likelihood of effecting positive nutritional change, but such investment is neither sufficient nor always necessary to effect change.     

Mapping critical levels of ozone,sulfur dioxide and nitrogen dioxide for crops,forests and natural vegetation in the United States

Air pollution abatement strategies for controlling nitrogen dioxide, sulfur dioxide, and ozone emissions in the United States focus on a ‘standards-based’ approach. This approach places limits on air pollution by maintaining a baseline value for air quality, no matter what the ecosystem can or cannot withstand. In this paper, we present example critical levels maps for the conterminous U.S. developed using the ‘effects-based’ mapping approach as defined by the United Nations Economic Commission for Europe's Convention on Long-Range Transboundary Air Pollution, Task Force on Mapping. This approach emphasizes the pollution level or load capacity an ecosystem can accommodate before degradation occurs, and allows for analysis of cumulative effects. We present the first stage of an analysis that reports the distribution of exceedances of critial levels for NO₂, SO₂, and O₃ in sensitive forest, crop, and natural vegetation ecosystems in the contiguous United States. We conclude that extrapolation to surrounding geographic areas requires the analysis of diverse and compounding factors that preclude simple extrapolation methods. Pollutant data depicted in this analysis is limited to locationally specific data, and would be enhanced by utilizing spatial statistics, along with converging associated anthropogenic and climatological factors. Values used for critical levels were derived from current scientific knowledge. While not intended to be a definitive value, adjustments will occur as the scientific community gains new insight to pollutant/receptor relationships. We recommend future analysis to include a refinement of sensitive receptor data coverages and to report relative proportions of exceedances at varying grid scales.