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排序方式: 共有190条查询结果,搜索用时 31 毫秒
81.
The ability of several adsorbents to adsorb dyes from solution has been studied and the relative costs of dye removal are reported based on adsorption capacity only. The application of the results to batch scale commercial systems has been discussed. A detailed study of the adsorption of Telon Blue dye on carbon has been undertaken using fixed beds and the data correlated into a design model using the bed depth service time (BDST) method of analysis. 相似文献
82.
G. McKay 《Water, air, and soil pollution》1991,60(1-2):117-133
Two solutions for the prediction of concentration vs time decay curves in agitated batch adsorbers, based on external mass transfer and pore diffusion, are presented and these enable mass transfer coefficients and pore diffusivities to be estimated by fitting to experimental data. Solutions have been developed for predicting concentration vs time decay curves for the adsorption of pollutants from water. The first solution, Model 1, applies a polynomial curve fit equation to the experimental concentration-time data and then differentiates the equation to yield dC/dt values at various time values. Certain problems were encountered in its application and therefore Model 2 was developed; this model uses an exponential curve fit equation and yielded results which were in better agreement with experimental data. Consequently a more rigorous program was developed to apply Model 2 to the experimental data. The solutions enable theoretical data to be compared with experimental results and ‘best fit’ external mass transfer coefficients and pore diffisivities to be determined for various systems. 相似文献
83.
The adsorption of a dyestuff, Telon Blue (Acid Blue 25) on Fuller's earth and Astrazone Blue onto fired clay has been studied. An intraparticle diffusion rate parameter has been defined characteristic of the rate of diffusion after the early stages of the adsorption. The rate parameter has been determined for a number of variables including adsorbent mass, initial dye concentration, and particle size. 相似文献
84.
Zeng R Farias FH Johnson GS McKay SD Schnabel RD Decker JE Taylor JF Mann CS Katz ML Johnson GC Coates JR O'Brien DP 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2011,25(2):267-272
Background: Bandera's neonatal ataxia (BNAt) is an autosomal recessive cerebellar ataxia that affects members of the Coton de Tulear dog breed. Objective: To identify the mutation that causes BNAt. Animals: The study involved DNA from 112 Cotons de Tulear (including 15 puppies with signs of BNAt) and 87 DNA samples from dogs of 12 other breeds. Methods: The BNAt locus was mapped with a genome‐wide association study (GWAS). The coding exons of positional candidate gene GRM1, which encodes metabotropic glutamate receptor 1, were polymerase chain reaction (PCR)‐amplified and resequenced. A 3‐primer PCR assay was used to genotype individual dogs for a truncated retrotransposon inserted into exon 8 of GRM1. Results: The GWAS indicated that the BNAt locus was in a canine chromosome 1 region that contained candidate gene GRM1. Resequencing this gene from BNAt‐affected puppies indicated that exon 8 was interrupted by the insertion of a 5′‐truncated retrotransposon. All 15 BNAt‐affected puppies were homozygous for the insert, whereas all other Cotons de Tulear were heterozygotes (n = 43) or homozygous (n = 54) for the ancestral allele. None of the 87 dogs from 12 other breeds had the insertion allele. Conclusions and Clinical Importance: BNAt is caused by a retrotransposon inserted into exon 8 of GRM1. A DNA test for the GRM1 retrotransposon insert can be used for genetic counseling and to confirm the diagnosis of BNAt. 相似文献
85.
Isolation in cell cultures and initial characterisation of two novel bocavirus species from swine in Northern Ireland 总被引:1,自引:0,他引:1
McKillen J McNeilly F Duffy C McMenamy M McNair I Hjertner B Millar A McKay K Lagan P Adair B Allan G 《Veterinary microbiology》2011,152(1-2):39-45
We report the isolation in cell cultures of two novel bocavirus species in pigs from farms in Northern Ireland with clinical postweaning multisystemic wasting syndrome (PMWS). We have designated the isolates as porcine bocavirus-3 (PBoV3) and porcine bocavirus-4 (PBoV4). To date 5082 and 4125 bps of PBoV3 and PBoV4 have been sequenced, respectively. PBoV3 and PBoV4 show nucleotide homology to other known bocaviruses in swine and other organisms. Open reading frame (ORF) analysis has shown that these viruses have a third small ORF, equivalent to the NP1 ORF that distinguishes the bocaviruses from other parvoviruses. A panel of porcine field sera was screened by indirect immunofluorescence against both viruses. Of the 369 samples analysed, 32 (8.7%) and 35 (9.5%) sera were seropositive for PBoV3 and PBoV4 respectively, thus providing serological evidence of the exposure of swine in the field to bocavirus-like viruses. To date, the clinico-pathological significance of these novel swine bocaviruses, as primary pathogens or as immunosuppresive triggers for other infectious agents, is undetermined. 相似文献
86.
Glass spherules show multiple high-velocity impact craters and are coated with small particles including glass, plagioclase, clinopyroxene, ilmenite, olivine, chromite, rock fragments, and frozen droplets of iron, nickel-iron, and troilite. These spherules passed through an impact cloud of hot fragmental material, condensing iron-rich vapor and high-velocity projectiles. Breccia contains concentric, accretionary lapilli units and appears to be a sintered deposit from a hot lunar base surge generated by impact. 相似文献
87.
Lunar samples 60017,4 and 63335,14 are composed of microbreccias and devitrified glass. These components are predominantly anorthositic, with the exception of a cryptocrystalline clast found in the microbreccia portion of 63335,14 which contains 2.7 percent potassium oxide and 66.7 percent silicon dioxide. The samples have been subjected to extreme shock and thermal metamorphism. The parent materials of the microbreccias include both a coarse-grained anorthosite and a fine-grained subophitic anorthositic gabbro. 相似文献
88.
89.
Discovery of vapor deposits in the lunar regolith 总被引:1,自引:0,他引:1
Lunar soils contain micrometer-sized mineral grains surrounded by thin amorphous rims. Similar features have been produced by exposure of pristine grains to a simulated solar wind, leading to the widespread belief that the amorphous rims result from radiation damage. Electron microscopy studies show, however, that the amorphous rims are compositionally distinct from their hosts and consist largely of vapor-deposited material generated by micrometeorite impacts into the lunar regolith. Vapor deposits slow the lunar erosion rate by solar wind sputtering, influence the optical properties of the lunar regolith, and may account for the presence of sodium and potassium in the lunar atmosphere. 相似文献
90.