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991.
Currently, the biomass of an invasive and obnoxious weed, kunai grass (Imperata cylindrica), is uncontrollably burnt in Papua New Guinea in subsistence farming systems resulting in unwarranted negative environmental consequences. We explored the possibility of sustainable utilization of biochar produced from the weed biomass along with a standard feedstock‐rice husk (Oryza sativa). Biochars were produced with lab‐scale pyrolysis at 550°C, characterized for chemical properties and plant nutrient composition. Further, agronomic efficacy of soil incorporation of biochars (5 t ha?1) or co‐applied with mineral fertilizers (100, 11, and 62 kg ha?1 N, P, K, respectively) was tested for sweet potato (Ipomoea batatas L. Lam) in a field experiment. The two biochars differed significantly (P < 5%) with respect to recovery from the feedstocks, chemical characters and nutrient composition. Kunai grass biochar was poorer in nutrients (< 1%) with distinctly alkaline pH and higher electrical conductivity. Biochar amendment to soil showed significant (P < 5%) improvement of soil moisture, while co‐application of biochars along with mineral fertilizers showed soil moisture decrease. Biochar amendment improved the growth parameters and total tuber yield of sweet potato by about 20%, while co‐application with mineral fertilizers augmented total tuber yield by 100% and above‐ground biomass yields by > 75%. Besides, improving agronomic performance of sweet potato crop, co‐application of biochars with mineral fertilizers enhanced uptake of N, P, K, Ca, Mg, and S. Production and utilization of biochar in sweet‐potato production could offer an efficient means of disposing biomass of kunai grass with concomitant productivity improvement in Papua New Guinea. 相似文献
992.
993.
X-ray diffraction patterns of transfer RNA consistent with the presence of short parallel helices in the molecule 总被引:1,自引:0,他引:1
X-ray diffraction data of yeast formylmethionine transfer RNA, Escherichia coli phenylalanine transfer RNA, and Escherichia coli arginine transfer RNA single crystals are compared with the Fourier transform of a helix. The results are consistent with the presence of short parallel double helical segments in the transfer RNA molecules. 相似文献
994.
为鉴定评价福建省三明市水稻联合体成员新选育的中籼迟熟品种在长江中下游稻区的丰产性、稳定性、适应性、抗逆性、米质及其它重要性状表现。2019年三明市水稻联合体开展长江中下游中籼迟熟组水稻新品种区域试验,参试品种13个,其中续试并生产试验品种2个,续试品种2个,新参试品种9个。试验结果,遂两优164可以申报审定,两优8699、创优9708生产试验,鸿两优6363、两优1899、智两优6522续试和生产试验,禾两优6868、广两优366续试。 相似文献
995.
Two varieties of mesta (Hibiscus sabdariffa) seeds were analysed for their proximate composition. Their protein (18.8–22.3%), fat (19.1–22.8%) and dietary fiber (39.5–42.6%) contents were found to be high. The seeds were found to be a good source of minerals like phosphorus, magnesium and calcium. Their lysine and tryptophan contents were also high. Sulphur containing amino acids were limiting in this seed protein and the chemical score of mesta seed protein was 40 and 57 for AMV-2 and Bhimili-1 varieties respectively. Mesta seed oil is rich in unsaturated fatty acids (70%), of which linoleic acid constituted 44%. Weanling rats were fed with 10% mesta seed protein before and after cooking for 4 weeks. Food intake of animals receiving raw mesta seed diets was significantly lower than those receiving cooked mesta seed diets as well as the casein control diet. Protein and dry matter digestibilities of raw and cooked mesta seed diets were lower than that of casein control diet. Cooking improved the food intake, gain in body weight, dry matter and protein digestibility of mesta seed diets. PER and NPU of cooked mesta seed diets were significantly higher than the corresponding raw diets. These results indicate that cooked mesta seed protein is of relatively good quality. 相似文献
996.
Biswas AK Rao GS Kondaiah N Anjaneyulu AS Malik JK 《Journal of agricultural and food chemistry》2007,55(22):8845-8850
A simple, specific, and rapid analytical method for the determination of trimethoprim (TMP) and three sulfonamide (SA) antimicrobial drug residues in buffalo meat is developed and validated. This method is based on a solid-phase extraction technique followed by high-performance liquid chromatography (HPLC)-photodiode array (PDA) detection. Target compounds were extracted from the meat by acetonitrile and water, cleaned up on a Bond Elute C 18 cartridge column, and separated on a RP-C 18 column during HPLC analysis. Acetonitrile along with water appears to be an excellent extractant as recovery of the analytes at maximum residues levels (MRLs) in spiked sample was in the range of 75-108%, with coefficient of variations (CVs) ranging between 1.34 and 22%. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.031 and 0.062 microg/g, respectively, for all of the compounds. Intra- and interday assay precisions of the method at 0.125 microg/g concentrations for any drug ranged between 3 and 4%. The linearities of the TMP, sulfadimidine (SDM), sulfadoxine (SDO), and sulfamethoxazole (SMX) were 0.9989, 0.9999, 0.9998, and 0.9997, respectively. For robustness, the analytical method was applied to 122 buffalo meat samples obtained from export meat processing plants. 相似文献
997.
介绍了微型生物群落监测法、指示生物法、污水生物系统、生物标志物等不同的湿地水生生物监测方法,并对未来的工作提出了展望。 相似文献
998.
B. Sarath Babu S.R. PandravadaR.D.V.J. Prasada Rao K. AnithaS.K. Chakrabarty K.S. Varaprasad 《Crop Protection》2011,30(4):389-400
Today India is the main producer of peppers especially the hot peppers, albeit mostly for domestic use. The thrips and mites, and the virus diseases transmitted by them along with fungal diseases like fruit rot, powdery mildew, bacterial wilt and leaf spots are the limiting factors in pepper productivity. The solution for managing these pests on a sustained basis exists in adopting eco-friendly approaches like using resistant cultivars. Fortunately huge natural genetic diversity exists in pepper and therefore, essential research efforts in finding out resistant sources and their utilization have been by and large dynamic and successful. Despite continuous scientific efforts there is a dire need for new cultivars with resistant traits for various pests suitable to varied climatic conditions, consumption and quality preferences all over the world. Efforts need to be intensified to find out useful genetic material and to introduce genes of resistance against insects, fungal and virus diseases into commercial cultivars. Genetic resources that have been used intensively in pepper breeding are for developing sweet peppers, hot peppers, bell peppers in various shapes, sizes and colors. Germplasm repositories at the World Vegetable Research Center (AVRDC) and United States Department of Agriculture (USDA) do possess number of genotypes resistant to insect pests, nematode, fungi, bacteria and virus diseases. At AVRDC resistant genotypes originating from several pepper growing countries to most virus diseases like Tobacco mosaic virus, Cucumber mosaic virus, Pepper veinal mottle virus, Chilli veinal mottle virus, Peanut bud necrosis virus etc., were identified from its rich pepper diversity. Exploitation of rich genetic diversity resulted in the development of new cultivars encompassing resistance to various pests and good agronomical traits. This has eventually resulted in meeting the demanding situations of diverse domestic as well as global production requirements. The chile database (Chile Database, 2010) highlights the exemplary utilization of germplasm and development of large number of cultivars and hybrids resistant to most diseases and nematodes around the world. This paper also depicts information on Indian sources of resistance to thrips, mites, leaf curl complex, nematodes and diseases, while presenting the scope for exploitation of diversity available in the Indian National Gene Bank and other repositories all over the world. An attempt is also made to identify the gaps in the genetic diversity and cultivars against the biotic constraints and the augmentation efforts required to be initiated toward enrichment of the gene pool for domestic as well as global use. 相似文献
999.
充分运用现代信息技术开展教学实践活动,有利于激发学生学习热情,实现最优化教学.福建林业职业技术学院教师在教学过程中,通过信息技术和多媒体演示,实现地形图三维动态演示教学,活跃了课堂气氛,激发了学生求知欲,在提高教学质量,建立新型师生关系等方面起到了良好作用. 相似文献
1000.
Govind Pratap Rao Madhupriya Ajay Kumar Tiwari Shailendra Kumar Virendra Kumar Baranwal 《Phytoparasitica》2014,42(3):349-354
During a survey of sugarcane fields at the Sugarcane Research Institute, Shahjahanpur, Uttar Pradesh, India, in August–September 2012, 6% to 28% incidence of sugarcane grassy shoot disease was observed in different fields of sugarcane variety CoS 7250. The association of phytoplasma with symptomatic sugarcane was confirmed by direct and nested PCR amplification of phytoplasma ribosomal gene. Four different delphacid leafhopper species, viz. Cofana unimaculata Signoret, Exitianus indicus (Distant), Sogatella kolophon Kirkaldy and Hishimonus phycitis (Dist.) were the prevalent feeding species of the Auchenorrhyncha fauna in the symptomatic sugarcane fields. Out of these four leafhopper species, only E. indicus tested positive for phytoplasma presence. Phylogenetic analysis suggested that the phytoplasmas from sugarcane and E. indicus in the present study were members of 16Sr XI. The confirmation of association of sugarcane grassy shoot phytoplasma in E. indicus population is important to understand the secondary spread of this phytoplasma in sugarcane plants. 相似文献