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991.
992.
Conventional mechanical method and mechanical method combined with vacuum freeze-drying technology were used to make the ultra-fine
powders of edible fungus (Auricularia auricular). The content of basic nutrients, amino acid, micro structure and their properties of raw edible fungus and the edible fungus
powders obtained with the two methods were analyzed and compared. The granularity size and micro-structure of the pulverized
samples were analyzed by SEM and TEM technology. The average granularity size of the edible fungus powder obtained with mechanical
method was 1–5 μm, while that obtained with mechanical method combined with vacuum freeze-drying process was 0.5–1 μm. The
ultra-fine powders of edible fungus obtained with the two methods had better water recovery capability and quality, and their
preserving time was longer than that of raw edible fungus. All the properties of the ultra-fine powders of edible fungus obtained
with the vacuum freeze-drying technology were evidently superior to that of the conventional mechanical method.
Biography: YANG Chun-yu (1975), female, Ph. D. in Engineering Technology Center of Forestry and Wood Workine, Machinery, Northeast
Forestry University, Harbin 150040, P. R. China.
Responsible editor: Zhu Hong 相似文献
993.
L. G. García-Montero J. L. Manjón S. Martín-Fernández G. Di Massimo 《Agroforestry Systems》2007,70(3):243-249
In Mediterranean pine forests, truffles and mushrooms generate greater profits than any other woodland products. However,
there are no studies on Tuber melanosporum Vittad. associated with pines. For this reason, we have carried out a study of this truffle in mountain woods with Pinus sylvestris L. and P. nigra Arnold subsp. salzmannii (Dunal) Franco, in central Spain. Two hundred and eight Tuber melanosporum burns were monitored for 7 years in five different habitats within the same geographical area. An ANOVA test confirmed significant
differences in carpophore production. In higher producing habitats, pines were less abundant. We also confirmed that in 433
burns, T. melanosporum was always unequivocally associated with the root base of Quercus or Corylus trees. Similarly, 14 truffle collectors confirmed that they had never found a single burn with carpophore production associated
exclusively with pines. Nevertheless, soil analyses indicated that the soil of these pine woods was very favourable to Tuber melanosporum. We therefore conclude that at present Pinus nigra
salzmannii and P. sylvestris are of little interest to Tuber melanosporum culture, as they hinder carpophore production. However, this study has also confirmed that Pinus nigra salzmannii and P. sylvestris mycorrhize easily with Tuber melanosporum, both in the laboratory and in natural environments. On this basis, we propose that pines may act as transmitters of T. melanosporum, although they do not induce fruiting. As a result, the commercial cultivation of Pinus nigra
salzmannii and P. sylvestris seedlings mycorrhized with Tuber melanosporum is not recommended in truffle culture at the present time. 相似文献
994.
以泡桐丛枝病类菌原体的敏感指示植物长春花苗为材料,用叶柄注射法注入感病泡桐叶汁液进行接种试验,结果表明,有1/4供试植株感病,其症状与泡桐丛枝病相一致,将感病植株叶脉切片镜检,发现有类菌原体,其形态、大小及结构,均与泡桐丛枝病类菌原体相同。为该病病原的传播及回接提供了一条简便的途径。 相似文献
995.
Antonella Puddu Nicola Luisi Paolo Capretti Alberto Santini 《Forest Ecology and Management》2003,180(1-3):37-44
A study was carried out in southern Italy to determine the role of some factors in favouring Heterobasidion annosum s. l. spread and damage in eight Silver-fir (Abies alba Mill.) forests. All the studied stands were colonised by H. abietinum. The presence of the fungus (as carpophores on colonised wood) was detected by means of transects and varied from 7.0 to 56.0% of trees. Stand history, precipitation and forest origin, analysed by the χ2-test, had a significant effect on rot severity. Damage was more severe in stands more xerophytic where the woods were planted on pasturelands. 相似文献
996.
The effects of applying N(urea, 46% N), P(phosphate, 12% P2O5) and K(potassium sulphate, 54% K2O) fertilizers on the growth performance and biomass yield of 8-month-old Archidendron clypearia seedlings were examined by L9 orthogonal array with 3 replicates in the nursery of Zengcheng Forest Farm of Guangzhou, Guangdong Province. The test seedlings were potted with the subsoil of total N 0.0484%, total P 0.1518% and total K 1.2629%, and fertilized at the 2nd and 6th months with the application rates of 0, 10 and 20 mg of N, 0, 20 and 50 mg of P and 0, 10 and 20 mg of K per seedling. The results showed that the diameter at ground level(DGL), the height and the oven-dried weight biomass of 8-month-old seedlings differed significantly at P=0.05. The combined application dose of 20 mg N, 20 mg P and 0 mg K per seedling resulted in the best seedling growth and biomass yield. N fertilizer was a significant factor in the growth of DGL and height of A. clypearia seedlings. P fertilizer had no significant effects on both DGL and height, while K fertilizer only affected DGL significantly. Analysis of the leaf and root stoichiometry suggested that N may be the most single limiting nutrient, A. clypearia seedlings used N more efficiently than they used P. 相似文献
997.
Costanza Di Stefano Vito Ferro Vincenzo Pampalone 《Land Degradation \u0026amp; Development》2016,27(2):239-247
Many process‐oriented erosion prediction models reproduce rill erosion as affected by site‐specific parameters, as for example, rill erodibility, and thus, their practical application requires the measurement of these parameters or their estimate. The aim of this paper was establishing a method for indirectly measuring field rill erodibility. A simple mathematical approach based on a known soil detachment equation and accounting for the rill erosion dynamic process is applied. Field measurements carried out for seven natural rainfall events occurring at the plots of the Sparacia experimental station, southern Italy, are used for indirectly measuring the rill erodibility of the investigated soil. This method needs only the knowledge of the geometric characteristics of the rills at the end of the erosion event and the event duration. The method was also tested by using the Water Erosion Prediction Project database, and this analysis showed that a reliable value of rill erodibility can be obtained by the proposed Equation 18 . The proposed method has the following advantages: (i) to be applicable at field scale, being more realistic than the laboratory scale because the soil structure is not destroyed, and (ii) to avoid the disadvantages of field experiments such as the cumbersome experimental set‐up and the large volume of water inflow needed. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
998.
A multi-body simulation approximate model of a vehicle using ADAMS software is established, and a frontrear suspension system, a steering system, the tires and all connectors are studied. Vehicle handling stability under different tests is simulated. The result is credible and valid, the parameter of vehicle model is amended expediently. This simulation can help design products and reduce a development cycle. 相似文献
999.
1000.
Statistical characterization of sicilian olive oils from the Peloritana and Maghrebian zones according to the fatty acid profile 总被引:1,自引:0,他引:1
Di Bella G Maisano R La Pera L Lo Turco V Salvo F Dugo G 《Journal of agricultural and food chemistry》2007,55(16):6568-6574
This paper deals with the characterization of 475 Sicilian virgin olive oils (VOO) produced in 10 different crop years (from 1993 to 2004), according to the cultivar and the geographical origin by means of multivariate statistical analysis applied to fatty acids. In particular, the studied VOOs came from the Peloritana and Maghrebian geological zones. The fatty acid composition was determined by using the official gas chromatographic method. The results suggest that although the effect of the cultivar is significant in the olive oil classification based on the fatty acid composition, a predominant and well-defined geographic effect is also present. This study demonstrated that it is possible to employ an official and inexpensive analytical method coupled with the statistical analysis to ascertain the geographical origin and the cultivar of an extra virgin olive oil. 相似文献