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101.
为分析不同石榴品种果实不同部位的酚类特性,以枣庄地区13个石榴品种成熟期果实为材料,利用比色法测定果皮、果汁和种子总酚、单宁、总类黄酮、原花色素、黄烷醇等的含量,采用DPPH清除法分析抗氧化能力。结果表明,各石榴品种间且同一品种不同部位的酚类物质存在明显差异,但均以果皮中酚类物质含量最高。‘软籽谢花甜’果皮总酚、单宁、总类黄酮含量均最高,种子总酚、原花色素、黄烷醇含量也最高,而‘小青皮酸’果汁中总酚、单宁含量最高。各石榴品种果皮、种子抗氧化能力和总酚、单宁、总类黄酮含量之间均为显著正相关,含量高的品种抗氧化能力也强。主成分分析将果皮、种子和果汁中5~6个酚类物质指标简化为2个主成分值来衡量酚类物质含量,不同石榴品种不同部位的主成分值不同。主成分值排在前5名的‘软籽谢花甜’是值得大力推广和深入开发利用的优良品种。可对酚类物质含量较高的石榴皮进行综合利用,开发相关产品。  相似文献   
102.
以四川省苍溪县工业园区为例,采用单因子评价法与箱式大气质量模型对区域大气环境质量进行评价与预测,结果显示,工业园所在区域环境空气质量符合《环境空气质量标准》Ⅱ级标准。工业园区SO2的大气环境容量为:284t/a,TSP为:950.2t/a,满足总量控制和环境容量要求。在此基础上,提出了源头把关+末端治理+跟踪监测的污染综合防治对策:1)严格执行政策总量控制,严把企业入园关;2)优化能源结构,推行清洁生产;3)加强宣传教育,树立科学发展观;4)加强评价后跟踪监测,督促环保措施落实到位。  相似文献   
103.
本文介绍了国际植物保护公约实施工作与能力发展的主要管理机构实施工作与能力发展委员会的产生历史因由、职责范围、议事规则等,并介绍了公约在实施工作与能力发展方面开展的工作和进展,就我国的应用方向、未来进一步的切入点提出了想法和建议。  相似文献   
104.
Soil properties varied in water retention; due to soil texture and organic matter content. Variations of texture in many soils are effected mostly to soil forming factors of parent materials of the soil; biological activities; climactic variation; and duration of soil reaction. While the organic matter contents are affected totally by the environmental conditions of the soils. Water holding capacity of different soils influences' plant growth and development in diverse soil characteristics of the world and determines soil productivity. Water resources for agricultural activities are limited, particularly in arid environment and soil water-holding capacity of arid soil is very low. Kuwait can be good example of arid environment with limited water resources for agriculture activities and possess soil of coarse texture with very low organic matter content (Anonymous, 1997). Agricultural development in Kuwait meets many problems for crop production and urban landscaping. Water resources are limited and the quality is deteriorating at the same time soil water holding capacity is very low. Enormous amount of water, particularly desalinated expensive water is wasted for agricultural activities. This paper will study various parts of Kuwaiti soils water holding capacity and develop water retention data for efficient water irrigation and improvement of plant growth.  相似文献   
105.
In soft wheat breeding programs, the gluten strength of flours from specific genotypes is determined by various chemical and rheological tests. Based on such tests, the experimental wheat lines with very weak flour gluten are typically selected for the production of soft-dough biscuits, while the lines with medium gluten strength and extensibility are reserved for hard-dough biscuits. Often, the genotypes having high gluten strength are removed from such breeding programs. In the present study, the usability of the GlutoPeak tester on whole wheat flour samples was investigated for assessing the gluten strength of soft wheat breeding materials. In the study, 25 soft wheat genotypes, grown in seven locations for three years, were categorized by commonly used gluten-quality-related parameters. Based on the results of the study GlutoPeak whole wheat flour PMT values ranging from 30.0 to 50.0 s and AM values from 15.0 to 20.0 GPU were found to be suitable for soft-dough biscuit products, whereas the values between 40.0 and 60.0 s and 20.0 and 23.0 GPU were appropriate for hard-dough biscuit products. The genotypes exhibiting AM values > 24.0 GPU and PMT values > 60.0 s were judged to have too-strong gluten, and thus eliminated from the breeding program. The gluten aggregation energy (AGGEN), and the torque after the maximum torque (PM) values were only useful and applicable to flours for soft-dough products. The maximum torque (BEM) values were not effective in discriminating against the genotypes. The results of this study demonstrated that the GlutoPeak whole wheat PMT and AM parameters can be recommended as quick and accurate parameters especially for early generation screening with small-scale tests in soft wheat improvement programs.  相似文献   
106.
郭兴华 《林产工业》2020,57(3):80-82
随着我国产品的商业附加值迅速提升,纸质包装机械生产企业的产能出现阶段性过剩,如何实现纸质包装机械生产企业去产能,成为许多企业亟待解决的问题。论述了我国包装纸行业概况,分析了包装纸机械市场需求,在此基础上,提出了纸质包装机械生产企业去产能措施。  相似文献   
107.
海河平原区十年九旱,水资源不足是这一地区农业生产发展的主要限制因素。但是,由于降水分布极度不均,涝灾也时常发生。针对这一气候特点,建立了一套与农田生态耗水相适应的跨流域调节的农田抗(旱涝)灾应变系统,为缓解水资源的不足开创了一条新路。  相似文献   
108.
Societal concerns about the social and environmental impacts of biofuel production are driving producers to adopt better management practices. Existing certification schemes for sustainable biofuel production are, however, biased towards industrial-scale producers that have the financial capital and economies of scale to meet sustainability and certification objectives. Smallholder farmers in developing countries, by contrast, often lack the means and capacity to do so. Some of the challenges faced by smallholders include high certification costs, insufficient institutional capacity, inadequate financial and social incentives, poor group organization and lack of external support. Drawing lessons from existing certification programs, we argue that proponents of sustainable practices and standards must fully appreciate the complex realities of smallholder production systems. We provide policy recommendations for ensuring that no farmer is left behind in the quest to increase sustainable biofuel production.  相似文献   
109.
Water-rock reactions are driven by the influx of water, which are out of equilibrium with the mineral assemblage in the rock. Here a mass balance approach is adopted to quantify these reactions. Based on field experiments carried out in a granito-gneissic small experimental watershed (SEW), Mule Hole SEW (~ 4.5 km2), quartz, oligoclase, sericite, epidote and chlorite are identified as the basic primary minerals while kaolinite, goethite and smectite are identified as the secondary minerals. Observed groundwater chemistry is used to determine the weathering rates, in terms of ‘Mass Transfer Coefficients’ (MTCs), of both primary and secondary minerals.Weathering rates for primary and secondary minerals are quantified in two steps. In the first step, top red soil is analyzed considering precipitation chemistry as initial phase and water chemistry of seepage flow as final phase. In the second step, minerals present in the saprolite layer are analyzed considering groundwater chemistry as the output phase. Weathering rates thus obtained are converted into weathering fluxes (Qweathering) using the recharge quantity.Spatial variability in the mineralogy observed among the thirteen wells of Mule Hole SEW is observed to be reflected in the MTC results and thus in the weathering fluxes. Weathering rates of the minerals in this silicate system varied from few 10 μmol/L (in case of biotite) to 1000 s of micromoles per liter (calcite). Similarly, fluxes of biotite are observed to be least (7 ± 5 mol/ha/yr) while those of calcite are highest (1265 ± 791 mol/ha/yr). Further, the fluxes determined annually for all the minerals are observed to be within the bandwidth of the standard deviation of these fluxes. Variations in these annual fluxes are indicating the variations in the precipitation. Hence, the standard deviation indicated the temporal variations in the fluxes, which might be due to the variations in the annual rainfall. Thus, the methodology adopted defines an inverse way of determining weathering fluxes, which mainly contribute to the groundwater concentration.  相似文献   
110.
The GlutoPeak®-Test (GPT) as a rapid small-scale technique was optimized to evaluate the gluten aggregation properties and to predict the loaf volume, on the basis of a multiyear and multilocation analysis of wheat samples, using different solvents. 5 % lactic acid and 1 % sodium chloride displayed significant GPT responses. Relationships between protein content, sedimentation value, GPT parameters and loaf volume were investigated. With 1 % sodium chloride, the torque 15 s before maximum torque (AM) presented the highest correlation with loaf volume of samples from 2013 to 2014 (r = 0.77, r = 0.63, p < 0.001, respectively). A multiple regression analysis indicated that the best prediction of loaf volume was a linear function of protein content and AM, explaining the variation in loaf volume by 63 % and providing an uncertainty of ±39 ml. The accuracy of the validation of the linear function leads to 64 % correct and to 36 % incorrect predictions of the loaf volume. This emphasizes that the application of the linear function of protein content and AM cannot replace the actual measurement of loaf volume, but it could be a useful rapid screening test in breeding for improved baking quality in bread wheat.  相似文献   
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