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161.
从内容、结构、技术层面,对美国的“市场与行政结合”模式、欧盟的“多元概率模型”、“环境行政合同救济制度”等理论技术方法进行归纳总结,以构建综合决策型的环境行政合同制度运用于合肥市高新区管理环境事务的具体实践中,并运用污染因子指数分析法对应用效果进行了综合评价。结果表明,构建的综合决策型环境行政合同制度在环境管理的实践应用中具有可行性与可操作性。  相似文献   
162.
毛刺类线虫系一类重要的植物外寄生线虫,其内包括一些可传播植物病毒的种类。本研究基于形态学和rDNA分子特征从我国海南儋州、云南呈贡和昆明、福建厦门等植物根围土壤样品中分离鉴定出8个较小拟毛刺线虫(Paratrichodorus minor)群体;通过对种群数量较大的海南儋州群体与福建厦门群体的形态及测量值比较,发现不同地理群体间主要形态测量值存在一定差异;各群体18S RNA区、r DNA-ITS1区、r DNA-ITS2区和28S RNA基因中D2D3区序列与Gen Bank已登录的较小拟毛刺线虫不同群体相应序列(AJ438053、AJ438054及AJ438056;KJ934126;JN123380和JN123381;JN123396和KJ513001)相似度分别介于99.1%~99.9%、95.8%~96.3%、99.5%~99.8%和99.4%~99.9%。对上述较小拟毛刺线虫群体r DNA-ITS1区、r DNA-ITS2区和28S RNA基因中D2D3区序列比较和酶切分析显示,该3段序列在较小拟毛刺线虫种内群体间都较为保守。其中28S RNA基因中D2D3区序列在种内群体稳定,种间群体有明显的差异,系毛刺类线虫鉴定一较好的分子靶标。有关结果对较小拟毛刺线虫的鉴定及鉴别有直接的指导意义。  相似文献   
163.
Morphological integration and modularity are concepts that refer to the covariation level between the components of a structure. Morphological modules are independent subsets of highly correlated traits. The horse skull has been studied as a whole functional structure for decades, but the integrative approach towards quantitative examination of modules is scarce. We report here the first evaluation of cranial modularity in the horse at basal level. For this, we studied the modularity hypothesis for splanchnocranium and basicranium modules in the horse, two phenotipic regions under local influence by soft-tissue–hard-tissue interfaces. Using geometric morphometrics to capture the shape and location, we examined both modules in a sample of 23 dry skulls belonging to Pyrenean Horse Breed using 57 two-dimensional cranial landmarks. Modules were compared through partial least squares analyses and Escoufier (RV) coefficient. We tested whether the integration (measured by Escoufier RV coefficient) of splanchnocranium and basicranium strength modules and their covariation pattern (as analysed by partial least squares analysis) subordinate and express similar integration results. A clear modularity was observed. The lack of disproportions in the skulls of domestic horse breeds (compared to dog and cat breeds, for instance) might be an expression of the lack of single modules to evolve. On the other side, integration might have a positive impact on survival as long as the selection pressure is along the trajectory of integrated variation.  相似文献   
164.
In order to achieve high competitive quality of bamboo products, it appears that bamboo strips with naturally different tonalities should be elaborately sorted into different classes according to their global color texture appearance. Inspired by the coarse-to-fine visual perception process of human vision system, this paper proposes a new surface grading approach by integrating the color and texture of bamboo strips based on Gaussian multi-scale space. The multi-scale representations of color texture for the original image of bamboo strips could be obtained and used to construct the multivariate image, each channel of which represents a perceptual observation from different scales. The multivariate image analysis (MIA) techniques are used to extract multi-scale features from the resulting multivariate image data. The characteristic images corresponding to typical classes are selected to build the model of the reference eigenspace. The novel testing images and the training images are all projected onto this reference eigenspace to obtain their representative feature clusters. And the Bhattacharyya distance is used to estimate the similarity of the representative feature clusters between the testing images and the training images in the eigenspace. Then a k-NN classifier is adopted to classify the testing images into the given classes of training images. Comparative experiments have been carried out on a set of actual bamboo strip images and the experimental results verify the effective discrimination of multi-scale color texture eigenspace features and good classification accuracy of the proposed surface grading method.  相似文献   
165.
运用传统形态测量方法和地标点方法对广东阳江和湛江两个短吻鲾的形态特征进行了分析。传统测量方法的主成分分析的前两个主成分(76.29%)能明显地区分出两个种群。相对扭曲主成分分析前3个主成分(64.03%)也能明显地区分出两个种群,但效果差于传统方法的主成分分析。网格变形图显示,两地短吻鲾的形态差异主要表现在头部。地标点法避免了传统的多变量形态测量方法的信息冗余、包含的形状信息不够完整等问题,并能够重建图形,突出局部的形变,能够直观地比较出研究对象之间的细微差别。研究亮点:地标点法是国外最新发展出并被广泛使用的形态测量方法,该方法以地标点的坐标来表示生物的形状信息,再通过旋转与重叠,用网格图形和相对扭曲分析样本间的形状差异。本文在国内首次使用该方法有效地区分了短吻鲾的不同地方种群。  相似文献   
166.
两种耳石分析法在鲚属种间和种群间识别效果的比较研究   总被引:6,自引:0,他引:6  
采用耳石传统形态测量法和傅里叶形态分析法,对281尾2龄长江凤鲚(Coilia mystus)和刀鲚(C.nasus)个体的矢耳石形态学作了分析,结果表明,采用传统的耳石形态测量法对凤鲚与刀鲚种间的正判率达90.9%,但2个刀鲚生态型种群之间的判别成功率仅为76.9%。而运用傅里叶耳石形态分析法,凤鲚和刀鲚物种间的识别率高达100%,2个刀鲚生态型间的识别率也提高至86.8%。可见,两种耳石形态分析法对鲚属种间的识别效果均很好,但对种群分析而言,傅里叶形态分析法可以取得更好的识别效果。  相似文献   
167.
牛宝权  李雪君  李跃峰  王满  张东峰 《安徽农业科学》2012,40(34):16562-16564,16609
[目的]为筛选出适宜许昌烟区种植的浓香型烤烟新品种。[方法]以NC89为对照,对6个烤烟品种CF213、中烟202、秦烟97、豫烟9号、辽烟17、龙江935的生物学性状、外观质量和经济性状进行比较分析,并对农艺性状与经济性状的关系进行多元分析。[结果]豫烟9号和龙江935的田间长势强,产量、产值高,抗病性强,外观质量好,可以在许昌烟区进一步示范验证;CF213和中烟202的田间抗病性差,尤其抗病毒病能力比对照差,CF213的产量和产值均比对照低;秦烟97与辽烟17的经济性状差,辽烟17抗病性差(感黑胫病)。产量与株高、叶数和径围之间呈极显著中度正相关;株高和径围对产量及产值的影响主要为直接作用,叶数对产量和产值的影响主要为间接作用。[结论]该研究可为许昌烟区烤烟品种的更新换代及生产推广提供科学依据。  相似文献   
168.
Patterns of geographical diversity, and the relationship between agro-morphological traits and fatty acid composition were assessed for 193 safflower (Carthamus tinctorius) accessions representing forty countries. Accessions were assigned to eight groups based on geographical proximity. Cluster and Principal Component analyses were performed to assess patterns of diversity among the accessions and to select the most distant accessions from each of eight groups for analysis of randomly amplified polymorphic DNA (RAPD) markers. There was a large amount of diversity for agro-morphological traits, fatty acid composition, and RAPD markers. Most correlations among different traits were rather low. Plant height showed a positive correlation with days to flowering (r = 0.63**). Palmitic acid was positively correlated with stearic acid and oleic acid values, and negatively correlated with linoleic acid (< 0.01). Oleic acid and linoleic acid showed a strong negative correlation (r = −0.89**). The first three principal components together explained 59% of the variation, however, neither principal component analysis (PCA) nor marker analysis revealed a clear relationship between diversity pattern and geographical origin. Accessions from some geographical regions tended to group together, such as accessions from South Western Asia, Central Western Europe, and the Mediterranean region. The correlation between the morphological matrix and the genetic matrix based on RAPD markers was not significant (r = 0.027). Wide diversity in safflower germplasm indicates a considerable potential for improving this crop for both agronomic and quality traits.  相似文献   
169.
基于土地利用变化建立土壤质量评价最小数据集   总被引:13,自引:1,他引:12  
基于研究区194个土壤样点数据,利用方差分析、主成分分析及其他相关统计方法确定了苏州市土壤质量评价最小数据集(MDS)。与先前研究不同的是,本研究将土地利用方式及利用年限对土壤质量的影响作为进入MDS的衡量标准之一;此外,计算了每个候选的土壤理化变量在所有主成分上的综合荷载,而不是只比较该变量在某一个主成分上的荷载就剔除其他变量,从而避免了丢失过多的土壤质量信息。最后对该方法的可靠性从不同角度进行了验证,对54个黄泥土样点、77个黄松土样点及所有194个样点数据分别采用该MDS确定方法,得到了同样的最小数据集。这说明该方法具有很好的稳定性、可重复性,加以完善后,本方法完全可以借鉴到其他地区,从而一定程度上能够克服由于我国地域广、各地情况差异大而采用不同的土壤质量评价方法,最后得到的评价结果难以比较的缺点。  相似文献   
170.
This study investigated the use of leftover biomass(rice husks) as the raw material for the biotechnological production of platform chemicals and biopolymers. Following the biorefinery concept, different acid hydrolysates were studied and resulted into a wide range of treatment strategies. Chemometrics were applied throughout the procedures in multivariate experimental conditions. By using the best hydrolytic conditions of 6.0% H_3PO_4, 135 oC(45 MPa) and reaction time of 62 min, 21.0 g/L sugar hydrolysates were produced; by using the best hydrolytic condition of 4.5% HNO_3, 135 oC/35 min, 16.1 g/L sugar hydrolysates were produced; and with the hydrolysates use of 1.5% H_2SO_4 and 1.5% HCl, 135 oC/62 min, 18.2 and 17.8 g/L sugar hydrolysates were produced, respectively. The highest productivity, in terms of fermentable sugars, reached 68% of integral cellulose/hemicellulose fraction and surpassed those found in the literature, with regard to the processing of rice husks, by considering just one step process. Sulfuric hydrolysate, detoxified with active carbon, was used to prove this proposal viability, resulting in a fermentation substrate for A. terreus(ATCC10020) and R. radiobacter(LMG196) strains(natural producers of bioproducts), which certified the feasibility of the proposal. The production of fermentable sugars from leftover biomass should encourage a search for new bioconversion routes, which can result in economic and environmental benefits and a spread of knowledge.  相似文献   
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