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31.
Kangyi Lou Anushka Upamali Rajapaksha Yong Sik Ok Scott X. Chang 《Journal of Soils and Sediments》2016,16(8):2081-2089
Purpose
Remediate metal contamination is a fundamental step prior to reclaim oil sands tailing ponds, and copper (Cu(II)) is the most abundant metal in the tailings water or oil sands process-affected water (OSPW). Biochars produced at four pyrolysis conditions were evaluated for sorption of Cu(II) in synthetic OSPW to explore different biochar potentials in removing Cu(II) from the contaminated water.Materials and methods
Pine sawdust biochars pyrolyzed at 300 and 550 °C with and without steam activation were investigated by batch sorption experiments. Isotherm and kinetic studies were conducted to compare the sorption capacities of the four biochars and to examine potential mechanisms involved.Results and discussion
For all the biochars, Langmuir and pseudo-second order models were the best-fit for isotherm and kinetic studies, respectively. According to the Langmuir parameters, the maximum adsorption capacities of the biochars produced at 550 °C were around 2.5 mg Cu(II)?g?1, which were 30-folds higher than those produced at 300 °C. However, steam activation did not cause any significant difference in the biochars’ sorption performance. The kinetic study suggested that chemisorption involving valence forces was the limiting factor of the sorption. In addition, ion exchange and precipitation were likely the primary mechanisms for Cu(II) sorption which outweigh complexation with functional groups on the biochars’ surface.Conclusions
Pine sawdust biochar produced at 550 °C without steam activation could be utilized as a sustainable and cost-effective material to remove Cu(II) from the OSPW.32.
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35.
Eight cross combinations of Zinnia elegans were made using two recessive nuclear male sterile lines crossed with four restorers using the North Carolina Design II statistical
method. Heterosis, combining ability and heritability was analysed using 12 horticultural traits and these demonstrated the
advantage of heterosis in hybrid breeding of Zinnia elegans. Heterosis served to increase the number of whorls of ray florets across capitulum and the number of branches, and also decreased
plant height, crown size, pedicel length and length of node. Thus, six horticultural traits were improved over mid parent
and best parent status to fulfill major breeding goals of this herbaceous flower. The traits of plant height, number of whorls
of ray florets across capitulum and pedicel length were primarily controlled by paternal additive effects, whereas crown size
was mainly controlled by non-additive effects. Number of branches and length of node were affected both by paternal additive
effects and non-additive effects. The ratio of general combining ability to specific combining ability indicated the importance
of additive genes in the expression of these traits. Among the parental lines, AH003A and restorer A3 were chosen as primary
female and male combiners, respectively. AH001A and restorer S5 were chosen as secondary combiners. The cross AH003A × A3
was determined as the most promising combination for producing potted plant characteristics, and AH001A × S5 was the best
hybrid obtained in this study for cut flower traits. The analysis of combining ability for the parental lines showed that
there was no causal relationship between general combining ability and specific combining ability effects. 相似文献
36.
作者就大蚕省力化养蚕技术进行了试点分析,分析了大蚕每日二回育,三回育的各项经济技术指标,提出了技术处理要点。 相似文献
37.
棉花和小叶杨小孢子母细胞中超数核仁的形成及动态变化 总被引:1,自引:0,他引:1
用光镜和透射电镜观察研究了棉花(Gossypium hirsutum)和小叶杨(Populussimonii)小孢子母细胞中超数核仁的发生和动态变化过程。超数核仁出现于减数分裂前(棉花)和减数分裂前期Ⅰ早期(小叶杨),产生部位是核仁组织者区域。超数核仁与主核仁有类似的染色特性,但体积小,数量丰富。在小孢子母细胞减数分裂过程中,超数核仁通过下述主要方式进入细胞质:一是在分裂中期和后期核膜暂时解体时进入细胞质中;另一是在核膜完整时通过状态的变化经核膜孔进入细胞质或以整体形式通过核膜外突并缢出进入细胞质中。小孢子母细胞中超数核仁的发生可能是大量迅速补给细胞质核糖体数量的一种机制,与孢子体转向配子体的发育有关。 相似文献
38.
A new saponin, cristatain (1), together with four other saponins, celosin A (2), celosin B (3), celosin C (4) and celosin D (5) were isolated from the seeds of Celosia cristata L. (Amaranthaceae). Their structures were established by chemical and spectroscopic analyses. For the first time, the saponins were found in C. cristata L. In addition, compound 1 exhibited significant hepatoprotective effect on carbon tetrachloride (CCl4)- and N,N-dimethylformamide (DMF)–induced hepatotoxicity in mice, which were evidenced by significant decreases in the values of asparate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) of serum and histopathological examinations compared to controls. 相似文献
39.
Exploring genetic diversity of rice cultivars for the presence of brown planthopper (BPH) resistance genes and development of SNP marker for Bph18 下载免费PDF全文
Gandhimani Ramkumar G. D. Prahalada Sherry Lou Hechanova Sung‐Ryul Kim Kshirod K. Jena 《Plant Breeding》2016,135(3):301-308
Brown planthopper (BPH) is the most devastating insect pest in rice‐growing areas. Information on availability of BPH resistance alleles and their sources enhances BPH‐resistant breeding programmes. In this study, 260 highly diversified rice cultivars or breeding lines were screened for the presence of five major BPH resistance genes (Bph10, Bph13, Bph18, Bph20 and Bph21) using gene‐specific markers. The analysis revealed that 137 of the 260 cultivars possess at least one BPH resistance gene. Bph10 was predominant while Bph20 was the least distributed. Moreover, two and three different resistance gene combinations were found in the cultivars. Molecular markers play an important role in molecular breeding programmes. A tightly linked PCR‐based co‐dominant Bph18 marker was developed, which is cost effective and time effective and simpler than available Bph18 CAPS marker (7312.T4A). We strongly believe that the identified BPH‐resistant cultivars can be used as alternative resistance gene sources and also as resource for novel BPH resistance genes. The developed Bph18 marker will be highly useful in molecular breeding applications of BPH‐resistant breeding programmes. 相似文献
40.
多效唑对丝瓜生长和产量的影响 总被引:1,自引:0,他引:1
本文研究了不同浓度的多效唑对丝瓜生长和产量的影响,结果表明:100mg/L和200mg/L处理,能使丝瓜株高降低、节间缩短、叶面积减小、茎增粗、比叶重增加,100mg/L处理比对照增产20.26%。 相似文献