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41.
基于人工神经网络的田间秸秆覆盖率检测系统   总被引:2,自引:0,他引:2  
以VC++为工具,田间实拍图像为研究对象,在分析田间秸秆和土壤纹理特征差别的基础上,设计了BP神经网络秸秆覆盖率检测系统.该系统采用了神经网络与纹理特征相结合的方法提取秸秆,并以纹理特征熵值为标准建立了网络输入层学习样本选取准则.人工模拟和田间试验表明,设计的BP神经网络秸秆覆盖率检测系统对田间秸秆的识别率达90%以上,秸秆覆盖率计算误差可控制在5%以内;与传统的拉绳法相比,检测效率提高50~120倍.  相似文献   
42.
The texture uniformity of rice cooked by electric rice cooker (ERC) will deteriorate during the heat preservation process. In this study, the uniformity of rice texture and water dynamic were investigated by means of physical property analyzer and low-field nuclear magnetic resonance technique. The water content, distribution and migration in rice were compared to illustrate the effect of heat preservation mode with different temperature at pot cover. The middle-upper layer of rice was drier and harder after 24 h of heat preservation in conventional mode, while the outer-upper layer of rice absorbed water, swelled or even broken. The difference of water content between the two parts was 6.55%, and the difference of hardness was 333.31 g. The relaxation signal indicated that the binding force between immobile water of the two parts and the rice matrix became weaker after heat preservation. By adjusting the heat preservation mode with higher temperature of the cover, the moisture content difference between the internal-upper layer and the peripheral upper layer was decreased to 0.39% after 24 h of heat preservation, and the hardness difference was reduced to 2.99 g. These mean that the texture uniformity of the whole pot rice after heat preservation was maintained.  相似文献   
43.
裸燕麦(Avena nuda L.)籽粒硬度与其在收获、清洗和加工过程中籽粒的破损程度密切相关,也对其加工品质和食用品质有重要影响。确定裸燕麦籽粒硬度检测方法是全面了解其籽粒硬度形成机制的基础。利用单粒谷物特性测定仪(single kernel characterization system,SKCS)和质构仪(texture analyzer,TA)检测10份在仓储含水量条件下裸燕麦籽粒的硬度。结果表明,SKCS法测得硬度值为负值,变幅为-47.69~-15.81,且数据准确性较差;经过对籽粒形变量、压缩位移和上样量的统计分析,TA法是随机选取100颗籽粒,在籽粒形变35%时获得压缩至籽粒0.30mm位移处的硬度值,变幅为13.87’33.59N,数据能准确代表该材料的硬度值。籽粒硬度值受籽粒物理结构的影响,SKCS法测得硬度值与籽粒长呈正相关,TA法测得硬度值与籽粒宽呈正相关,相关系数分别为0.64和0.65。在籽粒物理特性和硬度值准确度等因素的综合评价下,质构仪更适合用于检测裸燕麦籽粒硬度。  相似文献   
44.
Rheology of cake batter is considered an important parameter determining cake quality. It is thus frequently used to investigate structural changes in the process of cake making. However, little is known about the relation between batter rheological properties and cake's final properties, concerning volume and texture. In order to explore this relation an extensive experiment covering broad recipe variability was performed using an advanced experimental design approach and subsequent statistical analysis. The mixture of standard with pregelatinized wheat flour had significant main and interaction effects on most responses characterizing cake batter. Leavening acids and mixing time affected only a few of them. The simultaneous influence of ingredients and mixing time was clearly described. Measuring the batter rheological properties immediately after mixing gave sufficient information to significantly estimate in advance the volume of the cakes together with their cohesiveness. This methodology could improve the design of new bakery products with desirable volume and texture.  相似文献   
45.
[目的]为指导烟区土壤保育和烤烟平衡施肥提供参考依据。[方法]利用南平植烟土壤普查资料,分析了土壤质地现状、演变趋势及其与土壤养分的关系。[结果]0.01 mm黏粒平均含量42.15%±7.14%,CV为16.94%,其中轻壤土和中壤土占65.65%,重壤土占33.51%。土壤质地与全钾含量之间呈0.01水平显著负相关,与缓效钾含量之间呈0.05水平显著正相关,与有机质、全氮、全磷、碱解氮、速效钾、交换性钙和镁及有效硫、有效铁、有效锰、有效铜、有效锌、有效硼含量之间呈0.01水平显著正相关,且与土壤有效锰、有效硫、有效铜含量的关系最为密切。土壤质地分组后,其养分含量在组间存在显著或极显著差异。[结论]南平植烟土壤质地多数较为适中,耕性较好;但近10年来土壤0.01 mm黏粒含量呈增加趋势,对质地黏重的土壤应客砂改土。  相似文献   
46.
Obvious distinction between English and Chinese is hypotaxis and parataxis.Emphasis is laid upon the form in English texture while in Chinese upon the meaning.This disparity that Englsih is hypotaxis-prominent while Chinese parataxis-prominent is reflected on all texture cohesive devices,including reference,substitution,conjunction,lexical cohesion etc.Therefore in translation between English and Chinese,the attention should be paid to the characteristics difference so as to properly deal the two languages.  相似文献   
47.
We propose an approach to texture characterization and comparison that directly uses the information of digital images of the earth surface without requesting a prior distinction of structural ‘patches’. Digital images are partitioned into square ‘windows’ that define the scale of the analysis and which are submitted to the two-dimensional Fourier transform for extraction of a simplified textural characterization (in terms of coarseness) via the computation of a ‘radial’ power spectrum. Spectra computed from many images of the same size are systematically compared by means of a principal component analysis (PCA), which provides an ordination along a limited number of coarseness vs. fineness gradients. As an illustration, we applied this approach to digitized panchromatic air photos depicting various types of land cover in a semiarid landscape of northern Cameroon. We performed ‘textural ordinations’ at several scales by using square windows with sides ranging from 120 m to 1 km. At all scales, we found two coarseness gradients (PCA axes) based on the relative importance in the spectrum of large (> 50 km−1), intermediate (30–50 km−1), small (10–25 km−1) and very small (<10 km−1) spatial frequencies. Textural ordination based on Fourier spectra provides a powerful and consistent framework to identifying prominent scales of landscape patterns and to compare scaling properties across landscapes.  相似文献   
48.
土壤学始于对土壤剖面及其形态特征的观察,剖面发生层的划分与发生层边界特征的描述是土壤调查的基础。实地划分发生层需要丰富的土壤学实践经验,存在主观和缺乏统一划分标准的问题。以紫色土剖面图像为研究对象,采用K-means聚类和图像分割技术,结合图像的颜色特征(CIE Lab色彩空间)和纹理特征(Entropy)识别紫色土剖面发生层边界,并与实地划分的结果进行比较。结果表明:(1)CIE Lab色彩空间的a、b通道和Entropy纹理特征,可以划分出供试剖面的主要发生层(A、B、C)和基岩(R);(2)聚类识别的发生层数量和发生层深度与实地识别的结果基本一致;除Z2剖面的C层和Z6剖面的Ap层聚类识别与实地识别的发生层下边界深度相差较大(分别为13 cm和8 cm)外,其余发生层下边界深度相差均在3 cm以内;(3)聚类识别的发生层边界形状更为不规则,明显度更为模糊。K-means聚类和图像分割技术实现了紫色土剖面发生层边界的客观识别,可为土壤剖面智能辨识系统的开发提供科学参考。  相似文献   
49.
One of the most important challenges in pig farming is to overcome the initial anorexia of the pig at weaning. Since the use of palatable ingredients should facilitate the initiation of feeding at weaning, we have previously conducted a series of trials to measure the preference of pigs for different cereals. Preference is driven by odour and taste, but the physical and post-ingestive properties of the cereals could also have an effect. The present trial aims to study the relationship between the preferences for diets with 60% of rice, barley, sorghum or oats and their digestibility and physical properties. We measured the ileal and faecal digestibilities of dry matter, organic matter, and crude protein, and the proximal GIT emptying (from the flow of digesta through the ileal cannula) for 12 h after feeding. Particle size profile, viscosity, swelling and water retention capacity and texture (hardness, fragility, chewing effort and stickiness) of the four diets, were also measured. Pearson's correlation coefficients with feed preference were statistically significant (P < 0.05) for particle size profile and texture of the feeds. They tended to be significant (P < 0.1) for ileal digesta viscosity, faecal dry matter digestibility and proximal GIT emptying rate. Additional studies of palatability for cereals should consider these parameters in order to confirm this.  相似文献   
50.
Temporal development in product quality and copper status was investigated in Atlantic salmon (initial weight 2.3 kg) fed alginate-based moist feed (MF) or commercial extruded dry feed (DF). The fieldwork was conducted from January to May in sea-cages (800 m3) off the Norwegian west coast. The dry matter content (DM) in the muscle of the MF group was stable at about 32% throughout the experiment, while the DM of DF group increased linearly from 32% to 35%. Salmon were sampled for analyses of Cu status, fillet gaping, texture and pH in March and April. The serum Cu content of the MF group was highest in March, but no significant effect of dietary treatment was observed on Cu status of muscle or liver. The Cu level in serum and muscle decreased from March to April in both fish groups, but the hepatic Cu level showed no temporal changes. Gaping incidence and pH were higher in the MF group in April compared with the DF group and, for both fish groups, fillet gaping was higher and hardness was lower in April than in March. Variation in serum Cu level explained 32% of the variation in fillet hardness, and serum and muscle Cu level related negatively with gaping. At the end of the experiment the condition factor, and fillet and visceral fat contents were higher in the DF group, while sensory evaluated hardness and tastiness were similar for both dietary treatments. In conclusion, sampling time had a greater impact on Cu status, texture and gaping than dietary treatment during springtime in adult Atlantic salmon. Dietary treatment significantly affected body shape, and fat and dry matter contents.  相似文献   
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