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排序方式: 共有38条查询结果,搜索用时 15 毫秒
1.
甲基对硫磷人工抗原的合成与鉴定   总被引:23,自引:1,他引:23       下载免费PDF全文
根据甲基对硫磷的结构特征,分别从甲基对硫磷的硝基一端或磷酸酯基甲氧基一端引入一定长度的间隔臂和活性基团,设计并合成了4种结构的半抗原;针对各种半抗原所带活性基团的性质,通过多种方法制备了与不同的载体蛋白偶联的人工抗原。进行动物免疫后,得到了针对甲基对硫磷的高效价抗体。  相似文献   
2.
This article summarized that compound microorganisms had many advantages compared with single strain such as symbiosis, co prosperity co culture, so it can cut down the cost, unchain the feedback repression in fermentation and improve the efficiency of production. It described the resources, constitutes and physiological characteristics of compound microorganisms with examples, which displayed its superiority farther. It is showed that the application of compound microorganisms to the agriculture,industry,medicine and environment variable analyzed etc. The problems lying in the application of the compound microorganisms technology and some views on solving these problems. Compound microorganisms are expected to serve all the fields more and achieve more economic and social efficiency.  相似文献   
3.
ABSTRACT

Calcareous soils typically suffer from zinc deficiency and zinc sulfate is incorporated in many cultivated soils. Utilization of ZnSO4 has some kinds of interaction with soil particles and organic matter. In this study, the efficacy of two znic(Zn)-amino acid chelates (Zn-ACs) i.e., Zn-alanine (Zn-Ala) and Zn-glycine (Zn-Gly) on wheat (Triticum aestivum, cv. N91-8) growth characteristics and zinc concentration in wheat was examined under greenhouse conditions and compared to the a commercial ZnSO4. Results showed that Zn-Ala and Zn-Gly significantly increased the dry weight and shoot length of wheat in comparison to ZnSO4 treatment. Soil application of Zn-Amino acid chelates proved to be the most influential source of zinc in increasing wheat growth and yield indices. Number of fertile spikelet and grain yield increased significantly respectively compared to ZnSO4 treatment. Zn concentration and protein content of wheat grain in Zn-ACs treatment was significantly higher than the ZnSO4 treatment. Soil application of Zn-ACs caused a significant decrease in the grain phytic acid (PA) concentration and also phytic acid to zinc molar ratio in comparison with ZnSO4 treatment. According to the results, Zn-ACs could be utilized as a zinc fertilizer source for improving the zinc bioavailability in wheat.  相似文献   
4.
多目标综合评价系统的设计与实现   总被引:4,自引:0,他引:4  
针对多目标决策和评价问题,设计并实现了一个多目标综合评价系统。用户应用该系统时可以建立实际的方案指标体系模型;系统中采用层次分析法和比值法确定指标的权重,采用理想点法、优序法、线性加权法、等级法对方案进行评价,并在此基础上采用Copeland法进行综合评价。应用所设计的多目标综合评价系统对多类具体决策问题的方案进行评价用以测试本系统,结果表明,能为决策者提供比较客观公正的评价结果。  相似文献   
5.
We present a landscape model to investigate the ecological consequences and costs of different management regimes in semi-natural grasslands. The model integrates dynamic abiotic conditions, management (i.e. disturbance) regime and response of more than 50 characteristic plant and insect species by modelling the dynamics of relevant niche parameters as predictors for species distribution models. We compare our results for exemplary scenarios differing in spatial and temporal scales and exemplary species belonging to different functional groups through several steps of aggregation.Our analysis aims at the question whether an infrequent massive disturbance by rototilling can serve as a less expensive alternative to annual mowing for preserving the characteristic species composition of open dry grasslands in Southern Germany. Rototilling results in a shifting mosaic determining the habitat quality for plant and animal species that may reduce the survival of local or regional populations.For some meadow species as well as the encroaching shrub species, rototilling has a detrimental effect on regional habitat quality. Other species, e.g. weeds and annual pioneers, strongly benefit or show only negligible reaction. Since this is a multi-objective problem, there is a no magic bullet in selecting an optimum scenario of measures. But by visualising the trade-off between ecological consequences and costs, our model is a valuable tool for conservation managers providing a sound scientific basis for management decisions relying on available ecological knowledge. It is also an interesting example for a model describing complex communities in a relatively simple way, simultaneously considering the main driving factors.  相似文献   
6.
根据人工合成色素多为水溶性,升温可加速其溶解这一物理特性,经过简单的脱色处理,借以判断辣椒粉的颜色属于人为添加的色素,还是植物固有的色泽。淀粉定性试验是根据植物淀粉能与碘结合生成兰色化合物这一特异现象,用以确定掺入物的属性。  相似文献   
7.
我国农机综合作业水平影响因素的计量分析   总被引:1,自引:0,他引:1  
本文针对我国较高的农机动力水平对应较低的农机作业水平的实际状况,运用统计方法,研究了农机综合作业水平与动力水平的相关性,并建立双对数模型,对农机综合作业水平的影响因素——农机动力水平(顷均耕地农机动力)、自然禀赋(可机耕地比重)、制度因素(劳均耕地面积)、经济发展水平(人均纯收入)等进行了计量分析。结果表明,四类影响因素对农机综合作业水平影响程度有大小之分,且农机动力、可机耕地比重、劳均耕地面积都与农机综合作业水平呈显著的正相关关系,农民人均纯收入与农机综合作业水平呈负相关关系。  相似文献   
8.
人工合成甘蓝型油菜的花药培养   总被引:3,自引:0,他引:3  
对20个基因型的人工合成甘蓝型油菜进行了花药培养.结果表明,在Keller培养基上可以直接诱导出胚状体,胚状体的诱导率与基因型、培养基的添加物等有关.基因型不同,胚状体的诱导率也不同;在培养基中加入活性炭降低胚状体的诱导率,加入0 1mg·L-1的6 BA和0 1mg·L-1NAA能提高胚状体诱导率.  相似文献   
9.
赵志刚  富贵  邓昌蓉  杜德志 《作物学报》2013,39(7):1231-1239
为了揭示人工甘蓝型油菜早期世代遗传和表观遗传变异规律, 以A组合(大黄油菜×中花芥蓝) S0世代、B组合(大黄油菜×中迟芥蓝) S0和S1世代人工甘蓝型油菜为材料, 分别利用AFLP和MSAP技术检测基因组变化及甲基化模式变化情况。结果表明, 16对引物在A组合S0扩增到523条带, 其中4对引物扩增出9条变异带, 包括7条亲本缺失带和2条新增带, 分别占S0总条带的1.33%和0.38%;45对引物在B组合双亲植株扩增到1093条带, 只有1对引物检测到1条父本带型在所有S0植株中缺失, 约占S0总条带的0.09%;在B9子代F19-1~F19-16总共扩增得到1092条带, 变异带有10条, 占总条带的0.915%, 其中包括9条缺失带和1条新增带, 9条缺失带全部位于C基因组。MSAP检测发现, B组合S0植株中有3个位点发生了甲基化模式的改变, 全部位于A基因组, 甲基化模式改变位点占总检测位点的1.37%。研究还发现B组合S0世代一个植株出现可遗传的花色变异, 推测该表型变异与B组合人工甘蓝型油菜中C基因组变异有关。  相似文献   
10.
《African Zoology》2013,48(2):367-373
We evaluated the hypothesis that the regular use of the southern harvester termite, Microhodotermes viator, as food source by the armadillo lizard, Ouroborus cataphractus, originated as an adaptation to survive the summer dry season in a climatic regime where rainfall is highly seasonal. To do so, we determined the most important climatic predictors of the geographical range of this species. Climatic data were obtained for 130 localities where O. cataphractus is known to occur and 168 adjacent localities where it is known to be absent. For each locality, data for 10 climatic variables were extracted from the South African Atlas of Agrohydrology and Climatology database. We constructed a forward stepwise logistic regression model of the probability of O. cataphractus occurrence, based on the set of 10 climatic variables. The best model included, in order of importance, average monthly summer rainfall, mean annual precipitation, average monthly solar radiation, and the ratio of winter rainfall over summer rainfall as most significant predictors. The selected model predicted 88.80% of the presences correctly and 85.52% of the absences. In essence, O. cataphractus is restricted to the winter rainfall zone of South Africa, excluding the high-rainfall southwestern section. We postulate that the highly predictable seasonal rainfall and the ameliorating effect of the Atlantic Ocean on climates in the Namaqualand region, in particular, have provided a unique selective regime for the origin of group-living in O. cataphractus. Dependence on M. viator as food source developed to survive the summer-autumn period of low food availability and resulted in the evolution of heavy armour and group-living behaviour. The moderate winters and early spring temperatures allowed full capitalization on high arthropod abundance during winter–spring, thereby overriding the negative impacts of armour and group-living on foraging efficiency at the home crevice.  相似文献   
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