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141.
142.
蛋白酶微胶囊制备工艺及在干酪成熟中的应用 总被引:1,自引:0,他引:1
以明胶和阿拉伯胶为壁材,通过Box-Behnken设计响应面优化试验,采用冷冻干燥工艺制备蛋白酶微胶囊.将微胶囊添加到干酪中,测定pH 4.6可溶性氮总氮比、水溶性氮总氮比以及12%TCA可溶性氮总氮比,同时进行质构、SDS-PAGE、SEM分析.结果表明:明胶质量分数为3.8%、阿拉伯胶质量分数为3.7%、芯材添加量为6.4 mg/(100 mL)时蛋白酶微胶囊化效率达到93.4%;干酪中应用该微胶囊后使pH 4.6可溶性氮总氮比、水溶性氮总氮比以及12%TCA可溶性氮总氮比增加,酪蛋白逐渐被降解为小肽且质地改善,干酪成熟60 d后蛋白质微观结构破坏. 相似文献
143.
基因型和环境对面团流变学特性的影响研究 总被引:2,自引:0,他引:2
用揉混仪和质构仪研究了3个不同品质类型的冬小麦品种在8个不同的生长环境条件下的面团流变学特性,分析了基因型和环境对性状的影响及各性状间的相关性。结果表明:面团流变学特性受基因型(G)和环境(E)及其互作的共同作用,其中基因型方差均值>环境方差均值>G×E互作均值;从性状的表现看,基因型以济麦20表现最佳,环境以烟台点综合表现最好;相关分析表明,面团粘度性状与最大拉伸阻力、拉伸比、峰值时间、峰值面积和8min带宽呈显著负相关,而与延伸度呈显著正相关。最大拉伸阻力与峰值时间、峰值面积和8min带宽呈显著正相关。因此,进行品质评价时,可用质构仪测定的面团粘度特性对面团品质进行初步快速的评定。 相似文献
144.
145.
利用无人机图像颜色与纹理特征数据在小麦生育前期对产量进行预测 总被引:1,自引:0,他引:1
为了实现基于无人机的小麦产量快速预测,通过不同种植密度、氮肥和品种的田间试验,应用无人机航拍获取小麦生育前期(越冬前期和拔节期)的RGB图像,通过图像处理获取小麦田间颜色和纹理特征指数,并在小麦收获后测定实际产量。通过分析不同颜色和纹理特征指数与小麦产量的关系,筛选出适合小麦产量预测的颜色和纹理特征指数,建立小麦产量预测模型并进行验证。结果表明,小麦生育前期图像颜色指数与产量的相关性较好,而纹理特征指数相关性较差。对越冬前期利用单一颜色指数NDI构建的产量预测模型验证时,R为0.541,RMSE为671.26 kg·hm-2;对拔节期用单一颜色指数VARI构建的产量预测模型验证时,R为0.603,RMSE为639.78 kg·hm-2,预测结果比较理想,但不是最优。对越冬前期颜色指数NDI和纹理特征指数ENT相结合构建的产量预测模型验证时,R和RMSE分别为0.629和611.82 kg·hm-2,比单一颜色指数模型分别提升16.27%和减小8.85%;对拔节期颜色指数VARI和纹理特征指数COR相结合构建的产量预测模型验证时,R和RMSE分别为0.746和510.29 kg·hm-2,较单一颜色指数模型分别提升23.71%和减小20.24%。上述结果说明,将无人机图像颜色和纹理特征指数相结合建立的估产模型精度较高,可在小麦生育前期对产量进行有效预测。 相似文献
146.
In order to optimize the practical application of Penicillium oxalicum strain 212 (PO212) as a biological soil treatment, and to achieve optimal biocontrol efficacy, it is essential to understand how the physical environment influences on its survival and growth. The combined effects of temperature, water potential and soil type on the survival and growth of PO212 were monitored for 30 days in microcosms. Three levels of water potential (dry, intermediate, and wet), two temperatures (15 and 25 °C), and three soils with different physical–chemical properties were used to examine the temporal survival and growth of two PO212 conidial formulations (F1, dried conidia without additives and F2, dried conidia with additives). Traditional serial dilution (CFU) on potato dextrose agar (PDA) and quantitative real-time PCR (qPCR) were used to track the PO212 treatments in the different soils. The survival (CFU) of the F1 was greater than that of the F2. PO212 was able to grow (qPCR) and survive (CFU) at all temperatures and water potentials in the three soils tested. The highest growth and survival rate was observed under some drought stress and in more acidic soils. Regression models were developed for the combined effect of temperature, water stress and soil organic matter content related to the survival and growth of PO212 in soil microcosms. Finally, the growth rate was positively correlated with the survival rate. The results could be successfully employed as an empirical approach in the development and prediction of risk of PO212 failure to grow and survive in different environments. 相似文献
147.
Soil particle-size distribution (PSD) is a fundamental soil physical attribute with dominant influence on many other soil properties. Laser diffraction combined with multifractal analyses have proven to be useful to obtain precise information from PSDs. The aim of this work was to assess similitude or difference of PSDs sampled on plots of an experimental field and belonging to the same textural class using multifractal parameters. The field experiment consisted of two tillage treatments and two cropping systems. It was conducted following a randomized complete split-block design with four replications on a Humic Dystrudept. Tillage treatments were conventional tillage (CT) and no tillage (NT) while crop rotations were ryegrass-sorghum (RS) and ryegrass-corn (RC). Particle-size distribution analysis by the sieve-pipette and by laser diffraction corroborate that all the samples were assigned to the same textural class. Singularity spectra f(α) and Rényi spectra, Dq, showed that multifractal distribution was a suitable model for PSDs obtained by laser diffraction. However, in the range of moments − 10 < q < 10, the r2 values for the linear fits leading to a Rényi spectrum, Dq, were higher than those for the singularity spectrum, suggesting the former was better defined than the latter. No significant differences in multifractal parameters were found between plots with contrasted crop rotation, RS and RC. In contrast, Hölder exponent of order zero (α0) and several parameters derived from the left branch of both, the f(α) and the Dq spectra, were significantly different between CT and NT treatments. No effects of mixing by cultivation were detected in our work, so that differences in PSDs between no-tilled and conventionally-tilled plots were simply attributed to patchiness and variation on the experimental field. Multifractal analysis of PSDs measured by laser diffraction provides further insight in verifying patterns of between plot soil texture variations (i.e. randomness or trends) in completely randomized block designs. 相似文献
148.
Clayey silts involved in a landslide have been sampled to study the role of sediment composition in developing sliding surfaces. Five drillings enabled the collection of 46 samples and to define active slide surfaces and non-active surfaces (discontinuities). 相似文献
149.
不同质地棉田土壤对磷吸附与解吸研究 总被引:6,自引:0,他引:6
研究了不同质地棉田土壤对磷吸附与解吸的影响。结果表明:不同质地磷素等温吸附曲线与Langmuir、Temkin和Freundlich方程拟合度都达极显著水平,尤以Langmuir方程拟合度最高,相关系数均在0.94以上;磷吸持指数(PSI)、土壤最大缓冲容量(MBC)和吸附量均随粘粒含量的增加而增大,即粘土壤土砂壤土,而易解吸磷(RDP)、解吸量、解吸率和标准需磷量(SPR)呈下降趋势,即砂壤土壤土粘土。以Langmuir方程估算棉田土壤的需磷量,砂壤质棉田需磷量为12.87mgkg-1,壤质棉田需磷量为12.66mgkg-1,粘质棉田需磷量为10.00mgkg-1。 相似文献
150.