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F. Murilo T. LunaBreno S. Rocha Estélio M. Rola Jr.Mônica C.G. Albuquerque Diana C.S. AzevedoCélio L. Cavalcante Jr. 《Industrial Crops and Products》2011,33(3):579-583
This study proposes to evaluate rapid methodologies to estimate oxidative stability and biodegradability for mineral, vegetable and synthetic oil samples, using quick and simple experiments. The synthetic oil sample was obtained from castor oil, so the vegetable oil chosen for this evaluation was a sample of the crude castor oil source. The oxidative stability tests described enabled the comparison of synthetic lubricant samples and showed that their stability was lower than that of petroleum-based oil. However, the physico-chemical properties, such pour points and viscosity index, were improved and potentially interesting for lubricant applications. The biodegradability experiments were carried out using a model of bio-kinetics. These studies proved that synthetic lubricant samples were easily degradable (similar to crude castor oil) and showed half-life significantly lower than those of the mineral oil samples. 相似文献
43.
以合成肽为抗原建立口蹄疫病毒非结构蛋白抗体检测ELISA试剂盒 总被引:3,自引:0,他引:3
【目的】建立合成多肽抗原检测FMD NSP抗体的ELISA方法。【方法】固相法合成特异性FMDV NSP B细胞表位肽,将其偶联在BSA载体蛋白上,作为抗原包被在ELISA板上,制备检测抗FMDV NSP抗体的ELISA试剂盒,并对该试剂盒进行方法考核。【结果】抗原包被浓度选择2.5μg·mL-1;检测199份血清标本,与美国UBI商品试剂盒符合率达到96.48%,与国产3ABC ELISA比较,符合率为97.48%,显示极好的一致性。【结论】该合成肽ELISA试剂盒可以用以检测NSP抗体,从而鉴别FMD的自然感染与疫苗免疫,试剂盒特异性强,重复性好、稳定性高,操作简便。 相似文献
44.
Organic farming requires cultivars that are specifically adapted to this low input cropping system. Hence, organic farmers
and scientists joined in a participatory breeding approach to develop region-specific genotypes of spring faba bean for organic
conditions in Germany. A set of 49 genotypes with contrasting degrees of heterozygosity and heterogeneity was used in field
trials across five locations in Germany during 3 years 2004, 2005 and 2006. The material involved 18 inbred lines, their 18
polycross progenies, one blend of inbred lines, one blend of polycross progenies, one blend of hybrids and ten checks. Inbred
lines are uniform, thus giving the option to be specifically adapted; whereas the polycross progenies and synthetics (Syn-1;
predicted from the inbred lines and polycross progenies performance) are partly heterogeneous and heterozygous, thus giving
the option to evolve. Agronomic performance was assessed and a “personal appreciation” score of the material was assigned
to each genotype by each partner. This personal appreciation was strongly influenced by biotic and abiotic constraints faced
by the crop in each location and by the expected grain yield of the genotypes. Uniformity was apparently appreciated by organic
farmers. In all locations, the highest yielding inbred line yielded slightly better than the predicted highest yielding synthetic.
However, this slight disadvantage of the synthetic is very likely to disappear if the synthetic (Syn-1) is propagated during
successive generations. 相似文献
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郑州市行道树综合性能评价体系的构建与应用 总被引:2,自引:0,他引:2
根据河南省郑州市自然地理状况和对城市行道树的特殊要求,制定和应用了6个一级指标和36个二级指标对建成区现有行道树进行了综合性能评价,并将其分为4类树种,为今后行道树的调整和后期规划提供科学依据。 相似文献
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The theoretical utility of two alternative methods, random (r) and convergent (c) cross methods, of producing maize synthetics has previously been ascertained in two different genetic backgrounds (EPS20 derived from eight Reid inbred lines with origin from the US Corn Belt population “Reid”, and EPS21 formed from eight non-Reid inbreds). However, the agronomical consequences of using one or another methodology have not been tested. The objectives of the present study were to determine, in two genetic backgrounds, whether synthetics developed by the random and convergent cross methods differed in agronomic performance and to investigate whether some allelic changes previously observed by Butrón et al. [Butrón, A., Tarrío, R., Revilla, P., Malvar, R.A., Ordás, A., 2003. Molecular evaluation of two methods for developing maize synthetic varieties. Mol. Breed. 12, 329–333.] could be directly implicated in those differences. The synthetics and the diallel crosses among them, testcrosses of EPS20c and EPS20r to their Reid parental inbreds and testcrosses of EPS21c and EPS21r to their non-Reid parental inbreds were evaluated for grain yield in three trials in 2004 and 2005. Our results suggest that directional selection for germination, which occurs during the process of formation of synthetics using the random method (but absent with the convergent cross method) was responsible for agronomic and genetic differences between synthetics obtained by alternative methods from the same set of inbreds. Although selection for germination increased the yield performance of the synthetic obtained from the Reid inbreds, in a more heterogeneous genetic background, natural selection against non-competitive inbred lines at germination would be responsible for an important reduction of variability that would reduce yield. 相似文献
49.
As organic farming refrains from the use of agrochemical inputs, it is characterized by large environmental heterogeneity. Genotype × location interaction is expected to be larger across organic cropping areas than across conventional ones. When breeding for organic farming, it is important to identify an adequate breeding approach and type of cultivar. The objective was to investigate in the case of faba bean (Vicia faba L.) the effectiveness of local breeding (exploiting local adaptation) vs. formal breeding (exploiting broad adaptation) for grain yield in organic farming and to compare the performance of two types of cultivars: inbred lines and synthetics. A set of 18 inbred lines, their polycross progenies and 13 checks was tested in five locations in Germany from 2004 to 2006. Due to the large genotype × location interaction, local breeding generated higher gains from selection than formal breeding. Based on estimates of genotypic performance and variance of inbred lines and polycross progenies, the best synthetic cultivar at generation Syn-1 and the best inbred line cultivar were predicted. Despite the large variance among inbred lines available in local breeding, the highest performing entry in both breeding strategies was a synthetic, due to its partial realization of heterosis. 相似文献
50.
人工合成小麦与普通小麦杂交后代衍生群体的Rht8基因分析 总被引:1,自引:0,他引:1
【目的】四倍体小麦与节节麦杂交培育的人工合成小麦已广泛应用于国内外小麦品种改良。通过研究人工合成小麦与普通小麦杂交后代的Rht8基因型,有助于提高分子标记育种效率,也有助于Rht8 基因型的多态性研究,并为人工合成小麦在中国小麦品种改良和分子标记育种中的应用提供依据和方法;【方法】以引自CIMMYT的人工合成小麦分别与中国四川成都平原主栽普通小麦品种杂交、回交的BC2F2:6后代群体中选育的113份优良高代系和川麦38、川麦42、川麦43和川麦47育成品种为材料,采用特异引物的PCR 扩增和改进的聚丙烯酰胺凝胶电泳对其Rht8基因型进行了研究;【结果】在以syn768、Syn769、Syn780和Syn786人工合成小麦为亲本的117份后代衍生群体检测材料中,Rht8基因型频率为77.78%。从每一个人工合成小麦形成的小的后代衍生群体看,Rht8基因型频率各不相同。以syn768为亲本的后代衍生群体,Rht8基因型频率最高,为96.70%;在以syn769为亲本而育成的优良高代系和川麦38、川麦42与川麦43育成品种中,Rht8基因型频率最低,为71.64%;以Syn780为亲本的后代衍生群体中,Rht8基因型频率为73.68%,分离比率约为3:1;以Syn786为亲本育成的材料只有川麦47,该品种不含有Rht8该基因;【结论】不论父本或母本的Rht8的基因型状况如何,它们所产生的杂交后代材料Rht8基因的遗传是随机的。 相似文献