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31.
A challenge in machine vision is to develop algorithms for detecting a substance with an amorphous shape when measured responses of both the substance and the underlying target have similar characteristics. The challenge is exacerbated when responses for targets are highly variable both across and within discrete target units. An example of this problem is the detection of fecal contamination on apples. Feces on apples can be detected using differential fluorescence responses of contaminated and uncontaminated apple surfaces to UV excitation. However, responses of both feces and apples are due to the presence of chlorophyll-related compounds, and the response of apples varies within and between apples due to natural variation in the distribution of these compounds. We present a technique for normalizing the variability of intensity responses among targets based on a priori knowledge of the image dimensions and the approximate target size. Using this information, a linear equation is derived based on the approximate median intensities of the background and of the target. The median intensities are estimated by calculating a cumulative intensity histogram and using a priori estimates of the percentage of the area in the image occupied by the background and by a generic target. The image is scaled for uniform intensity power using this linear transformation. The benefits of using this technique are demonstrated using hyperspectral fluorescence responses to UV excitation of 48 Golden Delicious and 48 Red Delicious apples artificially contaminated with dilutions of cow feces. Results show that the uniform power transformation normalizes the intensity distributions of apple images and increases the contrast between contaminated and uncontaminated areas on apple surfaces; the coefficients of variation for the average intensities of uncontaminated apple surfaces at 668 nm for Golden and Red Delicious apples were reduced from 39 and 55%, respectively, to 5% for both varieties. 相似文献
32.
Berit Brandth 《Agriculture and Human Values》2002,19(2):107-117
Much international research haspointed out that farm women in a Westernagricultural context have not identified withthe ideas and politics of feminism. This issuehas troubled feminist scholars in the field,since much research has documented thesubordinate position of farm women. However,concerning the question of why farm women have notadopted feminism, assumptions ofprogress can be read: gender equality and emancipationof women will eventually take place once theagricultural sector has reached a higher stageof development; concerning universalism: thereexists a common women's identity and experienceof male oppression that forms the basis foridentity politics. The question may beidentified as a researcher question embeddedwithin the assumptions of the feminist researchcommunity, which struggles with establishing asubject-subject relationship between theresearcher and the researched. As such, it is thebasis for the production of partial, situatedknowledge and must be recognized as such. 相似文献
33.
Sidra Iqbal Muhammad Irfan Fouzia Tabassum Hafiz Abdullah Shakir Javed Iqbal Qazi 《东北农业大学学报(英文版)》2017,24(3)
Effects of dilute acid and acid steam pretreatments were inspected for cellulose production of Eucalyptus leaves through Box-Behenken design,a three variable factors for response surface methodology by Bacillus subtilus K~(-1)8.Maximum cellulose production performed in 250 mL erlenmeyer flask with submerged fermentation attained at 50℃,p H 5,140 r·min~(-1) for 24 h.Results showed the efficient cellulose production from acid steam pretreatment(being autoclaved at 15 Psi for 15 min)than acid pretreatment.The optimum condition for maximum carboxymethyl cellulas(CMCase)was 1.811 IU·mL~(-1)·min~(-1)(0.8%acid conc.,10 g biomass loading,6 h reaction time)and filter paper activity(FPase)was 2.255 IU·mL~(-1)·min~(-1)(1%acid conc.,10 g biomass loading,8 h reaction time).Whereas,the acid steam maximum CMCase activity recorded was 2.585 IU·mL~(-1)·min~(-1)(0.8%acid conc.,15 g substrate loading and 8 h reaction time)and the highest FPase activity was 2.055 IU·mL~(-1)·min~(-1)(0.8%conc.,10 g biomass,6 h reaction time then autoclaved).Results revealed that acid pretreated Eucalyptus leaves were better lignocellulosic biomass for cellulose production by submerged fermentation. 相似文献
34.
对齿轮箱传动在国内外低扬程泵站工程中的应用情况进行了综述和初步分析,提出的不同类型的齿轮箱可运用于不同功能和规模的泵站。根据低扬程泵站工程的特点,提出了选用齿轮箱传动的可靠性、高效性、经济性和运行维护便利性等基本原则,并参照国外的经验提出了齿轮箱选择的方法,可供泵站设计时参考。 相似文献
35.
研究Alcalase水解蛋白酶和Flavourzyme风味蛋白酶分步水解脱酚棉籽蛋白的最佳条件。以水解度为评价指标,采用Plackett-Burman(PB)设计和Box-Behnken响应面分析法对影响双酶分步水解棉籽蛋白的9个工艺条件进行筛选优化。双酶分步水解脱酚棉籽蛋白的最优操作条件为:先用Alcalase水解蛋白酶在底物浓度(w/v) 9.66%,温度60.5℃、pH 8.0、酶用量25000 U/g的条件下水解150 min,灭酶后再用Flavourzyme风味蛋白酶在温度50℃、pH 6.0、酶用量26576 U/g的条件下水解120 min。在此条件下水解液的水解度可达到42.73%。试验结果可为棉籽蛋白多肽的开发利用提供依据。 相似文献
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Elizabeth M. Lund Katherine M. James James D. Neaton 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1998,12(2):57-60
The randomized clinical trial (RCT) is a valuable research method for the evaluation of new treatment and prevention regimens in veterinary medicine. Reporting of clinical trials in other disciplines has not been complete. Without complete information on the conduct and results of a clinical trial, readers cannot optimize their use of the information presented. This report represents an objective review of randomized clinical trials in the veterinary small animal literature from 1986 to 1990. Results indicate that RCT reports in the small animal veterinary literature are incomplete. The importance of reporting on particular aspects of RCT research is described. 相似文献
39.
碳汇项目方法学可规范碳汇项目设计文件编制和计量监测工作,确保项目产生的减排量达到可测量、可报告、可核查的要求,是进行碳交易的必要条件。本文梳理了当前碳汇项目方法的现状、他山之石—林业碳汇方法学的主要内容、海洋渔业碳汇相关理论和标准的研究进展,并对我国海洋渔业碳汇研究、标准及碳汇项目方法学开发面临的问题进行了分析,提出了具体的建议,以期为渔业碳汇方法学的建立及早日进入碳汇交易市场提供科学参考。当前,清洁发展机制(Clean Development Mechanism, CDM)和核证碳标准(Verified Carbon Standard, VCS)开发了林业碳汇方法学及红树林、湿地和海草等蓝碳项目的方法学。目前,尚无有关渔业碳汇监测和计量的国际标准和国家标准。海洋渔业碳汇计量和监测等一系列方法学体系尚未建成,无法全面系统评估我国海洋渔业碳汇能力和可交易量,海洋渔业碳汇与我国经济发展尚未建立耦联关系。一批相关的行业标准正在研制过程中。但是,关于海洋渔业碳汇的时效性、计量方法等尚存在不确定性。对此,建议加强海洋渔业碳汇理论研究、建全海洋渔业碳汇计量的数据体系、建立海洋渔业碳汇的示范区域和关注收获贝藻类的合理利用,以解决目前有关海洋渔业碳汇的争议问题,促进海洋渔业碳汇项目开发方法学建立,推进我国渔业碳汇交易市场的发展,发挥海洋渔业在应对气候变化中的作用。 相似文献
40.
近年来,生命周期评价成为国内外可持续发展和环境保护领域新的研究热点之一。目前,国内生命周期研究主要集中在方法学和应用研究这两个方面,此外相关软件、数据库的开发应用也是研究重点。其中,方法学研究主要针对生命周期清单分析和生命周期影响评价;生命周期评价的应用研究则在行业、环境管理以及环境工程中均有体现。通过对国内LCA研究进展的回顾性评述发现,近年来我国生命周期评价在国际研究成果的本地化方法学上有了很大突破。另外,基于生命周期思想而开发的环境管理手段正逐步被企业和政府所接受并应用,此方面有大量的相关研究。在相关软件和数据库开发应用方面,多项研究正努力填补我国至今没有成熟的生命周期软件系统的空白。随着LCA研究和应用的逐渐深入,对权威的LCA基础数据库的迫切需求日益增长。 相似文献