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151.
Satoru Taniguchi Syuntaro Hiradate Katsutoshi Sakurai 《Soil Science and Plant Nutrition》2013,59(2):333-343
The changes of Al species in the presence of montmorillonite (Mt) with aging were investigated using 27Al-nuclear magnetic resonance and inductively coupled plasma atomic emission spectroscopy after extraction with 1 mol L-1 KCl. Composition of the Al species in a hydroxyaluminosilicate (HAS) solution with a Si/Al molar ratio of 0.63 without Mt was not appreciably affected by 42 d of aging. In the absence of Mt, the concentration of Al13 ([Al04Al12(OH)24- H2O)12]7+) in the HAS solution with a Si/Al molar ratio of 0.09 and hydroxy-aluminum (HyA) solution decreased during 42 d of aging, suggesting that degradation (or polymerization) of Al13 took place upon aging. In the presence of Mt, Al13 was adsorbed onto Mt from the HyA and HAS(0.09) solutions. The adsorbed Al13 was partly recovered by 1 mol L-1 KCl from HyA- and HAS(0.09)Mt complexes after 42 d of aging, suggesting that at least a part of the adsorbed Al13 was exchangeable and the rest was considerably stabilized by adsorption onto Mt. The desorption ratios of Al from the HyA- and HAS(O.09)Mt complexes accounted for 25 to 30% and 6 to 8% of total Al adsorbed, respectively. The species of Al desorbed from these complexes consisted mainly of Al13 and AlNON. The AlNON was attributed to electrically asymmetric Al including HAS and/or polymer HyA ions. 相似文献
152.
Makiko Watanabe Nobuhide Fujitake Hiroyuki Ohta Takushi Yokoyama 《Soil Science and Plant Nutrition》2013,59(2):411-418
The morphology and chemical composition of fungal sclerotium-like grains collected from the buried humic horizon of volcanic ash soil in Mt. Myoko were examined using a scanning electron microscope (SEM), energy dispersion xray micro-analyzer (EDX), and electron probe micro-analyzer (EPMA). A high C content, low level of Si and high concentration of Al characterized the grains considered to correspond to the sclerotia of Cenoccocum graniforme. The 27Al MAS NMR spectrum of the sclerotia showed the existence of 6- and 4-coordinated Al. X-ray diffraction analyses supported the presence of amorphous Al (ex. Al-humus complex) in the sclerotia. 相似文献
153.
德新油27是贵州省油菜研究所以黄籽双低隐性核不育系847A与黄籽双低恢复系20137配制成功的杂交组合.该品种于2009年12月通过长江下游区域审定.介绍了该品种的特征特性及高产制种技术. 相似文献
154.
Kraft lignins modified by radical sulfonation or alkaline oxygen treatment were rich in acidic groups, such as sulfonic acid,
carboxylic acid, and phenolic hydroxyl groups, and were effective as soil-conditioning agents, especially because of their
ability to trap aluminum ions eluted from soil under acidic conditions. Formation of complexes between aluminum ions and modified
lignins was examined using potentiometric titration and 27Al nuclear magnetic resonance (NMR) spectroscopy. Changes in the titration curve of a modified lignin by the addition of aluminum
ions suggest the release of protons after the formation of complexes between them. Disappearance of 27Al-NMR signals assigned to various aluminum ions by the addition of kraft lignin treated with alkaline oxygen was also attributed
to the formation of complexes. The relative ease of proton release because of complex formation between a modified lignin
and metal ions was as follows: Fe3+ > Al3+ > Cu2+ > Pb2+ > Mn2+ > Ca2+. This indicates that aluminum complexes are quite stable, and the aluminum ion is not exchanged with cations other than Fe3+.
Received: October 24, 2001 / Accepted: January 16, 2002
Present address: Asian Natural Environmental Science Center, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan Tel. +81-3-5841-7506;
Fax +81-3-5841-5230 e-mail: ukyoko@mail.ecc.u-tokyo.ac.jp
Part of this study was presented at the 11th International Symposium on Wood and Pulping Chemistry, Nice, June 2001
Correspondence to:K.S. Katsumata 相似文献
155.
ZHANG Yong-qiang WANG Zhi-liang WU Xiao-dong LIU Yu-tian ZHANG Hai-tao BAO En-dong 《中国农业科学(英文版)》2008,7(12):1516-1523
The method of immunohistochemistry assay for the detection of scrapie in Chinese Short-tailed Han sheep was established using monoclonal antibody. Genomic DNA was isolated from Chinese Short-tailed Hart sheep blood. Using the polymerase chain reaction technique, PrP27-30 gene sequence was amplified from Chinese Short-tailed Han sheep genomic DNA. By recombinant DNA technology, the recombinant protein of Chinese Short-tailed Han sheep PrP27-30 was obtained. Then, using standard methodology of myeloma cell fusion, a panel of monoclonal antibodies was generated. With mAbs, scrapie in Chinese Short-tailed Han sheep was detected by immunohistochemistry assay. The recombinant protein of Chinese Short-tailed Han sheep PrP27-30 was obtained and a panel of six hybridoma cell lines secreting specific antibodies to Chinese Short-tailed Han sheep PrP27-30 related to scrapie was obtained with one fusion between myeloma Sp2/0 and spleen ceils from mice immunized with the purified recombinant protein. Four hybridoma cell lines can be used in immunohistochemistry assay for the detection of scrapie in Chinese Short-tailed Han sheep. So that the special monoclonal antibody developed in author's institute can be used to detect PrP^sc of scrapie in Chinese Short-tailed Han sheep by immunohistochemistry in China. 相似文献
156.
Maize ovary development is linked to kernel formation. Soil water deficit results in ovary abortion because of low water potential (ψw) resulting in inhibition of photosynthesis from anthesis to silking stage. Thus, drought is a key factor causing yield losses in maize, especially near the time of pollination. Earlier studies have indicated that selenium (Se) maintains antioxidative defence systems and enhances sugar and starch accumulation. The effects of Se on maize ovary development were studied in drought stress conditions. Maize ovary development was studied through observations on starch, membrane integrity, fresh weight and dry weight in drought-treated or unstressed glasshouse-grown plants, and crop yield, yield structure, leaf, stem and ear biomass accumulation were also analyzed. Results indicated that Se increased the stress tolerance of the crop, even though ovary abortion was not eliminated by Se treatments under low ψw. Under well-watered control conditions, Se had also negative effects. When the first ear was not succesfully pollinated or the ovaries aborted, the plants developed more ears. Even though these later formed ears did not produce kernels, they significantly increased the dry weight of the plants under water deficit. It could be concluded that The optimal concentration for maize of Se applied through roots is about 0.01 mg kg^-1 (supplied as Na2SeO4) soil or less. 相似文献
157.
基于电子延伸序列,克隆并分析了猪脂肪特异性蛋白27基因.各种组织提取总RNA,利用设计的引物进行RT-PCR,PCR产物与pMD19-T连接后转化E.coli JM109,检测阳性克隆并测序.猪FSP27基因的cDNA序列,其全长为745bp,开放阅读框为11-72Top,编码有238个氨基酸.同源分析结果表明,猪FSP27的核酸序列与人、小鼠和牛的同源性分别为86%、77.6%、82.3%.氨基酸序列的同源性分别为83.2%、74.4%、79.3%.组织分布结果显示:猪FSP27基因在多种组织均有分布.克隆的猪FSP27基因并注册GenBank(Accession.EU395789). 相似文献
158.
159.
160.
禽白血病病毒斑点杂交检测方法的建立 总被引:3,自引:0,他引:3
为建立禽白血病病毒(ALV)斑点杂交检测方法,本研究采用RT-PCR技术扩增ALV群特异性p27抗原基因的部分片段,并以纯化的p27PCR产物为模板,合成地高辛标记探针,以此建立了ALV的斑点杂交检测方法。用该方法对4份疑似感染ALV的现地病鸡组织样品和18枚鸡胚进行检测,结果表明所有样品均为阳性,而且与PCR检测结果的符合率达到100%。该方法具有良好的特异性和敏感性,适应于ALV临床大规模检测。 相似文献