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91.
全反射X-射线荧光法分析茶叶中的矿质元素 总被引:6,自引:0,他引:6
用全反射X -射线荧光法 (TXRF)分析了江西婺绿和宁红茶的矿质元素含量。结果表明 ,所测茶叶中P、S、K、Ca的含量在 2 4 70~ 30 70 0 μg/g ;Mn、Fe在 2 0 6~ 10 70 μg/g ;Ti、Ni、Cu、Zn、Rb、Sr、Ba在 5 5~ 12 2 μg/g ;Pb含量均小于 4 0 μg/g (干基 )。宁红还表现出 ,品质越好 ,P、Ni、Zn含量越高 ,而K、Ca、Mn、Sr、Ba含量则相反。茶汤中K、Rb、Ni的浸出率为 30 5%~ 86 4% ;P、S、Mn、Cu、Zn、Sr为 11 6 %~ 4 2 4% ;Ca为 7 2 %~ 12 6 % ;Fe为 1 1% -2 6 %。茶汤中Ti、Ba、Pb的含量均低于TXRF法的检测限。宁红茶汤还表现出 ,品质越好 ,K、Ca、Mn、Zn、Rb、Sr的浸出率越高。但红茶汤中的K、Zn、Rb、Ni浸出率明显低于绿茶 相似文献
92.
华木莲植物群落的生态学研究 总被引:8,自引:3,他引:5
采用线路踏查和样方调查的方法,对华木莲SinomanglietiaglaucaZ.X.YuetQ.Y.Zheng植物群落中乔木树种的重要值,物种多样性、优势度、群落均匀度以及物种丰富度等指标进行了计测,并初步分析了群落类型、结构与特种多样性指数的关系以及该植物的生境和花木莲种群特征,最后指出华木莲为中性偏阳性树,在林内天然更新困难,在现状植被中,该种群为衰退种群。 相似文献
93.
稻属(Oryza L.)的核质互作效应研究 总被引:8,自引:0,他引:8
用6个栽培稻品种为核供体亲本,以O. Barthii、O. Glaberrima野生稻种以及分别属于Indica、Javanica和Japonica亚种的6个品种为细胞质供体亲本,通过核置换回交8-12代,育成8×6个同核异质代换系。观察了全部代换系的11个农艺性状,研究其中7×6个代换系对20个稻瘟病菌株和15个白叶枯病菌株的感病性反应。结果表明,核质互作因素对所研究性状和两种病菌的反应都表现出显著的遗传效应;其中核质互作导致的雄性不育是一主导效应。研究的结果又一次为稻核质互作导致不育提供这样的证据:以进化上较低级的种质为胞质亲本更可能获得雄性不育。初步认为,胞质的多样性在杂交稻育种上较之在常规品种选育上更为重要和迫切。设想把细胞质导致核质互作雄性不育的这一胞质特性作为稻种分类的依据之一。 相似文献
94.
95.
本文在分析万安县1989~1994年晚稻细菌性条斑病发生的历史资料和相关气象资料的基础上,应用灰色关联度选择预报因子,根据模糊综合评判原理组建模型,预报晚稻细菌性条斑病的流行趋势,经回测符合率达100%,并在1995年、1996年和1997年应用该模型指导万安县晚稻细菌性条斑病的防治,取得了显著的经济效益。 相似文献
96.
用电镜X射线显微分析法,研究铜在鲤(Cyprinus carpio)肝细胞和肾细胞中的分布和相对含量,从细胞水平探讨鲤的铜中毒机理。结果表明,铜进入鲤体内后,在肝细胞、肾细胞的溶酶体中分布最多,溶酶体旁、细胞核次之,细胞质内最少,中毒组与正常组差异显著。鲤中毒后肝细胞核膜扩张、线粒体呈空泡状,溶酶体数量增多、体积增大;肾小管上皮细胞核膜扩张,线粒体肿胀,嵴断裂。 相似文献
97.
温度对玉米螟赤眼蜂发育的影响 总被引:2,自引:0,他引:2
在实验室内以米蛾卵作寄主,观察了玉米螟赤眼蜂在5个恒温条件下(17,21,25,29,33℃)的发育羽化情况及成蜂寿命、产卵量和后代性比,实验中光照为14:10(L:D),相对湿度控制为75%.结果表明,玉米螟赤眼蜂完成一代所需的发育时间随温度的升高而减少,在17℃时完成一代需要25.12d,而在33℃时仅需要8.11d;在17~25℃成蜂羽化率最高,33℃时最低,其次是29℃;雌蜂的寿命在17℃时最长为219h,但随温度的升高而缩短,在33℃时仅为19.20h;在21.25℃范围内,雌蜂产卵量达到最高;所设定的5个温度条件下发育的雌蜂,其所产的后代中雌性均超过雄性,后代雌性百分率在17~29℃达到高峰,但在33℃时有所下降. 相似文献
98.
Many forest ecosystems in Germany are strongly influenced by emissions of pollutants like SO2 and alkaline dusts. To quantify and evaluate the consequences of long‐term fly ash deposition on forest soils, a study was conducted in pine stands (Pinus sylvestris) in the Dübener Heide in Northeastern Germany. This forest area has been influenced mainly by emissions from coal‐fired power plants and the chemical industry of the industrial region Bitterfeld‐Wolfen‐Zschornewitz since the early 1900. The study sites are located along a fly ash deposition gradient of 8, 16, 14, 18, and 25 km away from the main emission source in Bitterfeld (sites 1, 2, 3, 4, and 5, respectively). Samples of the organic horizons (Oi, Oe, and Oa) and mineral topsoil (0—10 cm) were taken in fall 1998 and analyzed for their ferromagnetic susceptibility and total ash content. Scanning electron microscopy (SEM) and energy dispersive X‐ray microanalysis (EDX) were performed on selected samples to differentiate between the pedogenic and atmospheric origin of the mineral components in the organic horizons. As a result of the long‐term deposition, ferromagnetic fly ash components are mainly accumulated in the Oe and Oa horizons of the forest soils studied. Ferromagnetic susceptibility was significantly higher (p ≤ 0.05) in the Oe horizon of sites 1 and 2 compared to sites 3, 4, and 5. Unusually high total ash contents for organic horizons of > 74 % were determined in the Oa at all sites. SEM revealed 3 distinct features of persistent fly ash deposits from coal‐fired power plants within the organic horizons that can be defined as ”︁stable glasses” with magnetic properties, aluminum‐silicate‐minerals, and slag fragments. SEM and EDX indicated that a great portion of the mineral particles found in the organic horizons of forests soils influenced by fly ash are from atmospheric sources. For detection of atmospheric lignite‐derived deposition into forest soils, the Oe and Oa horizons have to be considered as specific diagnostic horizons because they show indicative properties for such soils. 相似文献
99.
High water temperature influences the survival, growth, and maturation of fish. Genetically characterizing thermal tolerance
is one of the most important subjects in fish culture. To identify the genetic characterization of thermal tolerance, this
characteristic was compared among strains, and among parents and their offspring, in the guppy Poecilia reticulata. In the strain comparison, significant differences in survival rate were observed among the five strains examined, and between
females and males. Females exhibited greater tolerance than males in four of five strains examined. In the comparison between
parents and their offspring, stronger influence of female parent than of male parent was observed. Offspring obtained from
surviving females exhibited greater tolerance than those from dead females. This tendency was typically observed in male offspring.
The survival rate in male offspring obtained from dead female parents was lower than that of those from surviving females.
The high-temperature tolerance of male parents did not influence this characteristic in offspring as strongly as that of female
parents. These results suggest that the major gene or genes, which has a dominant resistant allele and a recessive sensitive
allele, are probably passed on by sex-linked inheritance, located on the X chromosome. 相似文献
100.