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971.
Liu T Langston ML Li D Pigga JM Pichon C Todea AM Müller A 《Science (New York, N.Y.)》2011,331(6024):1590-1592
We report a self-recognition phenomenon based on an assembly process in a homogeneous dilute aqueous solution of two nano-scaled, spherical polyprotic metal oxide-based macroions (neutral species in crystals), also called Keplerates of the type [(linker)??(pentagon)??]≡[{M(H?O)}??{(Mo)Mo?}??] where M is Fe(III) or Cr(III). Upon deprotonation of the neutral species, the resulting macroions assemble into hollow "blackberry"-type structures through very slow homogeneous dimer-oligomerization processes. Although the geometrical surface structures of the two macroions are practically identical, mixtures of these form homogeneous superstructures, rather than mixed species. The phase separation is based on the difference in macroionic charge densities present during the slow homogeneous dimer or oligomer formation. The surface water ligands' residence times of Cr(III) and Fe(III) differ markedly and lead to very different interfacial water mobilities between the Keplerates. 相似文献
972.
973.
Tripp TM Meiring JD Prochaska JX Willmer CN Howk JC Werk JK Jenkins EB Bowen DV Lehner N Sembach KR Thom C Tumlinson J 《Science (New York, N.Y.)》2011,334(6058):952-955
Outflowing winds of multiphase plasma have been proposed to regulate the buildup of galaxies, but key aspects of these outflows have not been probed with observations. By using ultraviolet absorption spectroscopy, we show that "warm-hot" plasma at 10(5.5) kelvin contains 10 to 150 times more mass than the cold gas in a post-starburst galaxy wind. This wind extends to distances > 68 kiloparsecs, and at least some portion of it will escape. Moreover, the kinematical correlation of the cold and warm-hot phases indicates that the warm-hot plasma is related to the interaction of the cold matter with a hotter (unseen) phase at >10(6) kelvin. Such multiphase winds can remove substantial masses and alter the evolution of post-starburst galaxies. 相似文献
974.
Joseph GUEVARA-LUNA Mario HERNNDEZ-GUZMN Nina MONTOYA-CIRIACO Luc DENDOOVEN Marina Olivia FRANCO-HERNNDEZ Paulina ESTRADA-DE LOS SANTOS Mara Soledad VSQUEZ-MURRIETA 《土壤圈》2023,33(2):312-320
In recent years, there has been a growing need to understand how salinity affects microbial communities in agricultural soils. Archaeal and bacterial community diversities and structures were investigated by high-throughput sequencing analysis of their 16S rRNA in two arable soils with low electrical conductivity(EC)(2.3 and 2.6 dS m-1) and a saline soil(EC = 17.6 dS m-1). The dominant bacterial phyla in the soils were Proteobacteria(relative abundance(RA) = 46.2%), followe... 相似文献
975.
Losso Jack N. Losso MerryJean N. Toc Marco Inungu Joseph N. Finley John W. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2021,76(3):270-280
Plant Foods for Human Nutrition - Since the outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that caused the coronavirus disease-19 (COVID-19), in December 2019, the... 相似文献
976.
Nahla Bassil Paolo Boccacci Roberto Botta Joseph Postman Shawn Mehlenbacher 《Genetic Resources and Crop Evolution》2013,60(2):543-568
The US Department of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository in Corvallis, Oregon, preserves more than 800 accessions of hazelnut (Corylus), including C. avellana cultivars and representatives of 10 other recognized shrub and tree species. Characterization and study of genetic diversity in this collection require cross-transferable markers, such as trinucleotide microsatellite or simple sequence repeat (SSR) markers and universal chloroplast SSR markers. We developed new SSR markers and evaluated 114 Corylus accessions representing 11 species and 44 interspecific hybrids. Eight of 23 SSRs generated easy-to-score alleles in all species and seven were highly polymorphic. For those seven, the average heterozygosity was moderate at 0.49, and mean allele number, genetic diversity and polymorphism information index were high at 11.71, 0.79 and 0.76, respectively. The three most polymorphic SSRs were CaC-C008, CaC-C040 and CaC-C118. Neighbor-joining (NJ) clustering and structure analysis agreed with classical taxonomic analysis and supported inclusion of C. maxima within the large polymorphic species, C. avellana. Analysis also indicated that C. californica is a distinct species rather than a botanical variety of C. cornuta. Six universal cpSSRs were polymorphic in Corylus and generated 21 distinct chlorotypes with an average of 3 alleles per locus. Diversity at these cpSSRs was high and ranged from 0.33 to 0.64, with an average of 0.54. Incongruence in NJ topologies between the nuclear and chloroplast markers could be attributed to chloroplast capture related to hybridization during the ancestral diversification of the genus, or to homoplasy. The phylogeographical relationships among the 21 chlorotypes in the 11 Corylus species support Asia as a refugium where several hazelnut lineages survived during glaciation and from which they continued to evolve after dispersal from Asia through the Mediterranean to Europe, and across the Atlantic and/or the Bering land bridge to North America. 相似文献
977.
Daniel W. Sweeney Joseph L. Moyer Douglas J. Jardine David A. Whitney 《Journal of plant nutrition》2013,36(9):1330-1340
Grain sorghum [Sorghum bicolor (L.)], grown on the often infertile claypan soils of the eastern Great Plains, requires attention to soil fertility. Experimental objectives were to determine the effects of phosphorus (P) and potassium (K) fertility levels, N application, and legume residual on grain sorghum production and stalk rot. Following alfalfa and birdsfoot trefoil, first-year sorghum yield was 7 Mg ha?1 and not affected by N fertilizer. In subsequent years, yield increases due to N were less than 20%. Sorghum yield increased at low P and K rates, especially with nitrogen (N) fertilization and was greater following birdsfoot trefoil than following alfalfa. In 1995 when fertilized with N, lodging and stalk rot severity were increased by P and reduced by K. In 1996, stalk rot severity was reduced by K fertilization. Grain sorghum, grown after legume crops, required minimal levels of P and K, especially when N fertilizer was added. 相似文献
978.
979.
Todd R. Gemeinhardt Nathan J. C. Gosch Jerrod R. Hall Kasey W. Whiteman Tim L. Welker Joseph L. Bonneau 《水产资源保护:海洋与淡水生态系统》2021,31(11):3326-3333
- Large-scale movement of fishes is a challenge for conservation and management in rivers, especially when individuals can cross jurisdictional boundaries.
- Assessing large-scale movement is particularly difficult during early life stages, especially when endangered species are involved. After hatching, free embryos of the federally endangered pallid sturgeon (Scaphirhynchus albus) drift long distances during development. Following the transition to exogenous feeding, individuals may continue to move downstream, resulting in a potential two-step migration.
- Tagged age-0 pallid sturgeon were stocked into the lower Missouri River, which provided an opportunity to assess pallid sturgeon dispersal as well as the hypothesized two-step migration. From July 2018 to April 2021, 79 individuals were captured, with most dispersing 200–800 km downstream from the stocking location.
- The observed dispersal of pallid sturgeon supports the two-step downstream migration hypothesis. This migration may lead to dispersal into the Mississippi River, which highlights the need for expanded monitoring into the Mississippi River for an effective evaluation of pallid sturgeon recovery actions. This study also reinforces the importance of inter-jurisdictional management and collaboration to better account for the large-scale movement of river fishes.
980.
Joseph T. Fuss 《Aquacultural Engineering》1984,3(1):31-37
Salt gradient solar collector ponds are economically feasible as a source of heat energy for hatchery rearing water. A pond 3 m deep and covering an area of 5000 m2 will supply approximately 2800 GJ of energy over a three-month period — enough for a one-year smolt program in an Atlantic salmon hatchery. The cost to construct such a pond is approximately $173,000, or the equivalent of seven years' fuel bills using conventional heating equipment. Although the technology is new and not entirely understood, existing ponds have proven to be relatively problem free and require only minimum maintenance. 相似文献