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891.
Intensification of cyprinid production has resulted in substantial increases in aquafeed demand for these species and a requirement for studies on new protein sources. Increased availability of presscakes from biodiesel crops may help to meet this requirement. The suitability of detoxified Jatropha curcas kernel meal (JKM), in combination with a dietary organic acid/salt blend (NDF), was tested in practical diets for juvenile common carp (Cyprinus carpio). Four treatment diets contained between 0% and 13.5% fishmeal with the fishmeal protein replaced by JKM (0%, 30%, 70%, and 100%). Four further diets of the same composition but including 0.5% NDF were also prepared, and all diets were fed to carps for eight weeks. There were no statistical differences in growth between diets containing JKM and the control. Furthermore, addition of dietary NDF significantly improved final weights, specific growth rates, feed conversion ratios, and protein efficiency ratios. Body composition analysis showed a significant impact of dietary JKM inclusion on increasing body lipid content. The addition of NDF showed a tendency to lower body lipid content (P = 0.11). JKM is a suitable protein source in diets for carp, and the inclusion of 0.5% of NDF proved to be beneficial.  相似文献   
892.
Plant growth simulation models have a temperature response function driving development, with a base temperature and an optimum temperature defined. Such models function well when plant development rate shows a continuous change throughout the growing season. This approach becomes more complex as it is extended to cool‐season perennial grasses with a dormant period and bimodal growth curves. The objective of this study was to develop such a bimodal growth model for tall fescue (Schedonorus arundinaceus (Schreb.) Dumort) in the Midwest USA based on multiyear measurement trials. Functions for bimodal growth were incorporated into the ALMANAC model and applied to tall fescue using published tall fescue yields for a variety of sites and soils. Fields of cultivars “Kentucky 31” and “BarOptima Plus E34” were divided into paddocks and sampled weekly for dry‐matter accumulation. These biomass estimates were used to derive weekly growth values by differences between sequential weekly samplings. The measured values were compared to a single tall fescue simulation each year on one soil. Using these results, the ALMANAC model was modified and tested against mean reported tall fescue yields for 11 sites, with one to three soils per site. When we introduced midsummer dormancy into ALMANAC, we assumed dormancy began on the longest day of the year and lasted until the photoperiod was 0.68 hr shorter than the longest. ALMANAC simulated previously reported tall fescue yields well across the range of sites. Thus, ALMANAC shows great promise to simulate bimodal growth in this common cool‐season grass.  相似文献   
893.
The Australian perennial shrubs, oldman saltbush (Atriplex nummularia) and rhagodia (Rhagodia preissii), can complement the diets of sheep grazing moderate‐quality cereal residues. We compared liveweight change, organic matter digestibility, nitrogen and mineral balance, wool growth and methane emissions of Merino wethers offered oaten hay (OMD 622 g kg?1 DM; N 9.74 g kg?1 DM) with and without shrub biomass (substituted at 25% of OM). Diets were fed at restricted levels for 1 month. Substituting hay with shrub biomass significantly decreased liveweight loss, increased clean wool growth and increased apparent absorption of phosphorus compared to the hay alone. Substitution of hay with both saltbush and rhagodia led to over 23% greater clean wool growth. Nitrogen balance and apparent digestion of organic matter, calcium and magnesium did not vary significantly between animals on the diets. Wethers on the rhagodia and hay diets had similar enteric methane emissions, while animals offered the saltbush diet had significantly higher emissions (L/OM intake). When methane is expressed in terms of wool growth, animals on the rhagodia diet produced 26% less methane for every gram of wool.  相似文献   
894.
Anthocyanin concentration and composition and the effect of steaming and baking on these were evaluated in tubers of Korean red- and purple-fleshed potato cultivars and breeding clones using liquid chromatography with diode array detection and electrospray ionization-mass spectrometry (LC-DAD-ESI-MS). Twenty-six anthocyanins were isolated, of which 24 were identified. Remarkably, five cis isomers were identified, of which four, viz., cis-petanin, cis-peonanin, petunidin 3-cis-caffeoylrutinoside-5-glucoside, and petunidin 3-cis-feruloylrutinoside-5-glucoside, are reported for the first time. Moreover, pelargonidin 3-p-coumaroylrutinoside-5-glucoside (pelanin), peonidin 3-p-coumaroylrutinoside-5-glucoside (peonanin) and petunidin 3-p-coumaroylrutinoside-5-glucoside (petanin) were identified as the principal anthocyanins. We found that the total anthocyanin content of coloured potatoes was decreased by steaming and baking compared with the raw state. In addition, we performed partial least square discriminant analysis (PLS-DA) to discriminate between the analyzed anthocyanins. Cis isomers seemed to play a vital role as a biomarker in the PLS-DA model based on the type of processing and colour of the tubers.  相似文献   
895.
Although thermally conductive composites that can efficiently dissipate the heat generated from electronic devices are in high demand, most neat polymers used as matrix materials are problematic because they have poor thermal conductivities. The low thermal conductivity of polymeric materials is caused by structural defects; therefore, it can be improved by increasing the orientational regularity of the polymer chains. Here, main-chain liquid crystalline polymers (LCPs) were designed and synthesized to investigate the effects of liquid crystallinity-induced structural regularity on the thermal conductivity of the polymers. In addition, an in-situ polymerization method was devised for commercial applicability, and the thermal conductivity of the obtained polymer was compared to that of a conventionally polymerized polymer having the same structure. The designed polymers exhibited thermotropic liquid crystalline characteristics, and the polymer with longer spacers between the rigid segments showed relatively higher thermal conductivity exceeding 0.5 W·m-1· K-1 after sample preparation by injection molding. In addition, X-ray diffraction analysis revealed that the differences in the thermal conductivity, depending on the molding temperature during specimen preparation, were caused by variations in chain orientation within the same polymer. Based on the obtained results, it was concluded that LCPs are strong candidate matrix materials for thermally conductive composites; the suggested in-situ polymerization method could be applied practically to the polymerization of polyester-type LCPs.  相似文献   
896.
The successful isolation and characterization of water hyacinth fiber (Eichornia crassipes) (WHF) nanocellulose is presented in this study. The novelty was in exploring a wider range of properties of highly purified samples of WHF after each stage of production in more depth. The isolation was accomplished by pulping in a digester and sonication. Morphological changes before and after treatment were demonstrated by scanning electron microscopy (SEM). The lignin and hemicellulose content decreased during chemical treatment. Transmission electron microscopy (TEM) and particle size analyzer (PSA) were used to determine the morphology of WHF after sonication for 1 h. TEM shows that the diameter and length of nanocellulose WHF were 15.61 and 147.4 nm, respectively. The crystallinity index and crystalline domain area significantly increased after chemical treatment. The highest crystallinity index was 84.87 % after an acid hydrolysis process. The increase in crystallinity leads to good thermal stability. Moisture absorption tests of WHF were carried out before and after treatment. The lowest moisture absorption was in the cellulose fiber after sonication (nanocellulose).  相似文献   
897.
Vegetatively propagated crop (VPC) seed tends to remain true to varietal type but is bulky, often carries disease, and is slow to produce. So VPC seed needs to be handled differently than that of other crops, e.g., it tends to be sourced locally, often must be fresh, and it is less often sold on the market. Hence, a framework was adapted to describe and support interventions in such seed systems. The framework was used with 13 case studies to understand VPC seed systems for roots, tubers, and bananas, including differing roles and sometimes conflicting goals of stakeholders, and to identify potential coordination breakdowns when actors fail to develop a shared understanding and vision. In this article, we review those case studies. The framework is a critical tool to (a) document VPC seed systems and build evidence; (b) diagnose and treat coordination breakdown and (c) guide decision-makers and donors on the design of more sustainable seed system interventions for VPCs. The framework can be used to analyze past interventions and will be useful for planning future VPC seed programs.  相似文献   
898.
An essential part of the wild blueberry cropping system is the proper management of agrochemical inputs including herbicides, fungicides and insecticides. A machine vision system was developed and mounted on the rear sprayer boom 0.18 m in front of the sprayer nozzles capable of targeting the agrochemical application on an as-needed basis. The three-point hitch mounted sprayer featured 27 nozzles over a 13.7 m boom width and a storage tank capacity of 1135 l. Nine digital color cameras continually take images in real-time while computer software processes the images in 0.15 s to determine the target locations where the nozzles open and spray at speeds up to 1.77 m s?1. Two wild blueberry fields in central Nova Scotia were selected for smart sprayer performance testing with spot-application (SA) of agrochemical as compared to control and uniform application techniques. Chateau® herbicide was applied in a field with an infestation of hair cap moss. Spray droplet comparison showed moss patches were properly targeted using the smart sprayer. SA provided the same coverage performance as compared to uniform on the moss targets with herbicide application savings of 78.5% using the smart sprayer. Harvestable yield results were similar for all application tracks. TruPhos Magnesium and ZincMax foliar fertilizers were tank mixed with Bravo® and Proline® fungicides and applied to compare the difference of SA, control and uniform application. Results showed SA of foliar fertilizer and fungicide led to less premature leaf drop and increased the blueberry stem height, number of branches, stem diameter and fruit buds. SA of foliar fertilizer and fungicide also increased the percent of healthy wild blueberry plants by 57.8% and the harvestable yield by 137.8%. Fungicide application savings using the smart sprayer for SA were 11.6%.  相似文献   
899.
This study develops a method to evaluate the contact coolness of fabric using the infrared thermal image of a small test specimen. By using infrared thermal images of 7 types of fabrics developed as cool fabric, the average temperature difference on the surface of the human palm and a heating plate, with and without fabric was measured and this was used for the scale of the ability of the fabric to cool by touch. By comparing the average temperature differences with the Qmax of a fabric, absorption coolness, subjective contact coolness, and correlations were investigated. More heat is transmitted via fabric when the Qmax value is higher and average temperature difference of thermogram image is smaller, which means the coolness perceived by the skin becomes stronger. Fabric with a small average temperature difference in infrared thermal imaging had a high Qmax value and it was evaluated as having strong coolness in subjective evaluation too. However, it was found that there was no relationship between average temperature differences and absorption coolness. Therefore, it can be concluded that the evaluation of fabrics’ coolness using infrared thermal image is useful when evaluating contact coolness at the point of physical contact. In addition, by comparing the methods using the palm and heating plate, the method using the palm showed higher correlation with Qmax (-.828, p<0.05). Therefore, we confirmed that evaluating the coolness of small test specimens using an infrared thermal camera and the palm is effective.  相似文献   
900.
We report the isothermal and non-isothermal crystallization kinetics and associated transcrystalline morphological features of polyarylate(PAR)/nylon6 islands-in-a-sea fibers, where 74 PAR islands serve as reinforcing fibers and nylon6 sea component acts as a semicrystalline matrix in final thermoplastic composites. The temperature-dependent polarized optical microscopic images obtained during a cooling process exhibit that the melt-crystallization is dominated by the interfacial crystallization of nylon6 on the surface of PAR fibers, leading to developing a transcrystalline structure. From the isothermal and non-isothermal melt-crystallization analyses of the islands-in-a sea fiber by using differential scanning calorimetry and the Avrami equation, the overall crystallization rates of the nylon6 sea component in the islands-in-a-sea fiber are found to be highly accelerated by the heterogeneous nucleating effect of the PAR island fibers. In addition, it is revealed that the isothermal and non-isothermal melt-crystallization kinetics of the nylon6 in the islands-in-a-sea fibers consists of two different mechanisms of the primary crystallization owing to the interfacial crystallization and the secondary crystallization due to the bulk crystallization.  相似文献   
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