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81.
Investigations were conducted to understand the direct effects of rising temperature and the host-mediated effects of elevated CO2 (eCO2) on Spodoptera litura (Fabricius) (Noctuidae: Lepidoptera). This study involved i. the construction of life tables of S. litura at six constant temperatures viz., 20, 25, 27, 30, 33 and 35°C ± 0.5 °C reared on peanut (Arachis hypogaea L.) grown under eCO2 (550 ppm) concentration in open top chambers ii. Estimation of threshold temperatures and thermal constants and iii. Prediction of the pest scenarios during near and distant future climate change periods. Significantly lower leaf nitrogen, higher carbon and a higher relative proportion of carbon to nitrogen (C:N) were observed in peanut foliage grown under eCO2 over ambient CO2 (aCO2). The mean development time (days) of each stage, egg, larva, pupa, pre-oviposition and total life span decreased from 20 to 35 °C temperature on eCO2 foliage. The thermal requirement of S. litura from egg to egg (within the range of 20 °C–35 °C) was 538.5 DD on eCO2 as against 494.5 DD on aCO2 foliage. Finite (λ) and intrinsic rates of increase (rm), net reproductive rate (Ro), mean generation time (T) and doubling time (DT) of S. litura varied significantly with temperature and CO2 and were found to have quadratic relationships with temperature. The present results on life table parameters estimated by the bootstrap technique showed that the ‘rm’ values of S. litura on eCO2 foliage were higher than those in the literature indicating a significant influence of eCO2. The reduction of ‘T’ was noticed from a maximum of 50 days at 20 °C to minimum of 22 days at 35 °C and ‘λ’ which is the indicator of reproductive value of new eggs was highest at 35 °C and showed a negative relationship with temperature. The data on these life table parameters were plotted against temperature and two non-linear models developed for both CO2 conditions and used for predicting the pest scenarios. Prediction of pest scenarios based on PRECIS A1B emission scenario data at eleven peanut growing locations of the country during near future (NF) and distant future (DF) climate change periods showed an increase of ‘rm’ and ‘λ’ with varied ‘Ro’ and reduced ‘T’. The present results indicate that temperature and CO2 are vital in influencing the growth and life table parameters of S. litura and that pest incidence is likely to be higher in the future. 相似文献
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Temperature-dependent development of Ascotis selenaria (Denis et Schiffermüller) was studied in the laboratory. Time to egg eclosion decreased with increasing temperature and ranged from 17.4 d at 16 °C to 5.0 d at 30 and 32 °C. Total development times of larvae decreased from 54.7 d at 16 °C to 17.3 d at 32 °C. The development time of pupae ranged from 29.7 days at 16 °C to 10.2 days at 30 and 32 °C. Eggs, larvae and pupae did not develop successfully to the next stage at 12 and 35 °C. The estimated lower temperature thresholds were 10.4, 9.3, and 9.8 °C for eggs, larvae, and pupae, respectively. Thermal constants of egg, larvae, and pupae were 88.5, 370.4, and 188.7 DD, respectively. Stage emergence models for eggs, larvae, and pupae of A. selenaria were constructed by using the development rate model (Lactin 2 function) and development distribution model (three-parameter Weibull function), which simulate the proportion of individuals shifted from one stage to the next. Pearson's correlation coefficients between actual observations in the field and model outputs were statistically significant with 0.99, 0.68 to 0.87 and 0.96 to 0.98 for egg, larval and pupal stage emergence model, respectively. The egg stage emergence model could be used to facilitate spraying time as it successfully predicted the first instar larval population. Predictability of the pupal stage emergence model was greatly improved when the physiological age of overwintering pupae was assumed to be in various state. The stage emergence models developed here should be useful to construct an A. selenaria population model. 相似文献
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“茶百戏”是盛行于我国宋代的经典茶汤游戏,融茶艺与书法绘画于一体,既能饮茶保健,又可陶冶情操,雅俗共赏,情趣盎然。本文从关注老年人的身心健康出发,通过对武夷山老年人的娱乐方式的问卷调查和焦点访谈,发现了老年人现有的娱乐方式的不足,从而别出心裁地试图搭建“茶百戏”通向老年人茶叶消费群体的桥梁,在论证将传统茶百戏引入老年人的娱乐生活中的可行性的基础上,提出了相应的改进建议,因此,本文对于传承和弘扬“茶百戏”文化遗产及创新老年人娱乐方式均具有重要的指导价值。 相似文献
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中国茶向世界传播的途径与方式 总被引:1,自引:0,他引:1
中国是茶的原产地。现在茶树、茶客遍布世界,世界上有关茶的语音、种茶知识、制茶方法、品茶技艺、饮茶风俗及茶文化都与中国关系密切,茶树也直接或间接由中国引种。这一局面的产生是中国茶向世界传播的结果。千余年来,中国茶借助文化交流、经贸活动、人口迁徙等途径向世界传播,传播途径具有立体性、多样性、复杂性等特点,宗教人员、外交人员、经贸商人、移民侨民成为茶传播的主体。与此相适应,中国茶向世界传播的方式主要有知识方式、消费方式、产业方式,传播方式呈现直接传播、间接传播、综合传播相结合,反映了茶叶传播循序发展的递进过程。 相似文献
89.
茶叶是当阳乡村振兴的特色产业之一,在地理标志公共标识品牌玉泉仙人掌茶的引领下,茶叶经济效益逐年提升。本文通过对当阳茶叶产业发展现状调查与分析,总结存在的问题,提出对策与建议 相似文献
90.
为筛选出适宜与烤烟套种的甘薯品种,解决部分烟区烤烟种植调茬难度大与综合效益低等问题,通过田间大区试验,研究烤烟套种不同甘薯品种对烟叶质量、烟薯产量及土壤温湿度的影响。结果表明,烟薯套种能够明显提升土壤相对含水率和烟叶产量,其相对含水率提高幅度介于12.03%~91.88%,烤烟产量增幅为12.29%~31.26%。烤烟套种甘薯以紫薯产量最高,块根产量达29400 kg/hm 2,且单薯质量大于100 g占总薯重的比例在紫薯中最高。烤烟套种甘薯提升了烤烟中上部烟叶的总糖和还原糖含量,降低了烟碱和总氮含量,有利于改善烟叶内在品质。烤烟套种甘薯降低了上部烟叶含梗率,但增大了上部烟叶叶面密度,以烤烟套种紫薯表现突出。烤烟与紫薯套种,可作为一种烟田增产、烟叶增值和烟农增收的种植模式。 相似文献