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91.
试论农业科技创新人才的培养   总被引:3,自引:0,他引:3  
喻国华 《安徽农业科学》2006,34(2):325-325,327
分析了我国农业科技人员的现状及存在的问题,探讨了培养农业科技创新人才的有关对策。  相似文献   
92.
韶山市松材线虫病预防存在的问题及对策   总被引:1,自引:1,他引:0  
松材线虫病是松树的一种毁灭性流行病。松材线虫病的预防关系到一个地区林业生态安全与经济发展,探索松材线虫病预防工作的有效措施更是一个严峻的课题。该文分析了近几年来韶山市松材线虫病的预防形势,介绍了在利用天敌昆虫防治松材线虫病方面所做的工作,并指出韶山市松材线虫病防控存在的问题与应对措施。  相似文献   
93.
(续2012年第4期13页)1.加强领导,强化行政推动一是高度重视。坚持把发展粮食生产作为农业调结构、转方式、强基础、惠民生的重要工作来抓,全力巩固和扩大粮食生产成果。召开全县农业农村工作会议,全面部署全年的农业农村及粮食生产工作。组织召开全县控制水稻直播专题会议。县委书记田自力、县长黎作凤和分管农业副县长多次深入全县各乡镇,调研粮食生产,  相似文献   
94.
The correlation dimension evolution characteristics of acoustic emission(AE) time-series during the instability and failure of coal with and without gas are analyzed base on fractal theory. The results show the coal rock’s AE time-series of deformation stages have obviously fractal characteristics under uniaxial loading. The processes of AE of deformation have different self-similarity, and the correlation dimension can describe the mechanical state of coal. During the triaxial loading process, the stress-varying trend of AE time-series of coal with and without gas is similar to the trend of AE correlation dimension. The sharp decrease of AE time-series’ correlation dimension can be considered as a “precursor” for failure. This feature doesn’t change with the change of confining pressure and gas pressure.  相似文献   
95.
In order to understand the effect of runoff retention and pollution load control for vegetation roofs during rainfall events, the evaluation criterion of vegetation roof performance is redefined and two vegetation roofs are established artificially based on the code for the design of roof greening, which is investigated during rainfall events. Results show that ophiopogon japonicus roof can delay the production of runoff by 25〖XC半字线.tif,JZ〗48 min compared to the rain occurring and retention runoff volume by 40%〖XC半字线.tif,JZ〗58%, while sambucus dhinensis roof can make the generation of runoff 60〖XC半字线.tif,JZ〗130 min later than the rain beginning and runoff volume retention can be as high as 54%〖XC半字线.tif,JZ〗80%. In addition to PO 3-4 P, the reduction of pollution load of NO -2 N, NH3 N, TP, COD, TN and NO -3 N by both vegetation roofs can reach 95.1%〖XC半字线.tif,JZ〗98.6%, 87.2%〖XC半字线.tif,JZ〗93%, 72.4%〖XC半字线.tif,JZ〗83%, 76%〖XC半字线.tif,JZ〗81.8%, 68.7%〖XC半字线.tif,JZ〗78.4% and 40.9%〖XC半字线.tif,JZ〗60.6% respectively. The level of pH, COD, NH3 N and TP in vegetation roofs runoff can meet class Ⅲ surface water standard. Meanwhile, both vegetation roofs have similar effect in neutralization acid deposition (i.e., from 5.8〖XC半字线.tif,JZ〗6.0 (in rain water) to 7.0〖XC半字线.tif,JZ〗7.6 (in eco roof runoff water)). Plants grown on vegetation roofs can influence the performance of vegetation roofs. Based on the results, ophiopogon japonicus has an advantage of sambucus chinensis in controlling phosphorus pollution, while sambucus chinensis manifests better in reducing nitrogen load. Vegetation roofs are becoming an important urban landscape more and more, and study results in this paper provide references for the improvement of vegetation roofs construction and more reasonable evaluation of their running performance.  相似文献   
96.
Now increasing customer Quality of Experience(QoE) has become a key factor to maintain competitiveness and improve business income. The paper lays emphasize on addressing the influence from technology element, and builds up a model of mapping network key performance indicators to QoE value by the SEM analysis method. A table is provided for calculating QoE value, which can get the short board of network performance directly. The effectiveness and feasibility of optimizing QoS parameter are discussed to improve QoE level of data service.  相似文献   
97.
通过对株洲市水果产业的发展优势、树种、品种与产区分布、发展现状的深入调查分析,针对当前产业存在问题,提出了加快结构调整步伐,加大提质增效力度;建立优势产区,优化区域布局;实施科技兴果战略,推进科技创新;培育水果相关产业,推进水果产业化进程等建议来推动株洲水果产业的发展。  相似文献   
98.
文中收集了近年来对术科类专业的大学生进行课堂英语教学改革的相关研究成果,提出了以手机在线为辅助教学手段的课堂结构模式,并对这种教学模式从课堂试验方面进行了比较全面的阐述。  相似文献   
99.
To research the relation among the erythrooytic membrane liquidity and the contents of MPA, the activity of SOD in serum of the milk goat with fluorosis. An animal model with fluorosia was constructed, and the fluorescent probe technique of DPH was used to measue the erythrocytic membrane liquidity. At the same time, the contents of MPA and the activity of SOD in serum were measured. The results showed that the erythrocytic membrane liquidity in the control group and flurosis group were 5.6742 ± 0.4417 and 3.7248 ± 0.4521 (P <0.01) respectively, the contents of MPA in serum were 2.0408 ± 0.198 and 4.494± 0.438 (P <0.01) respectively, the activities of SOD were 175.638 ± 22.201 and 113.714 ± 34.258 (P <0.01) respectively. The correlation analysis indicated that the relation between the activity of SOD and the liquidity of erythrocytic membrane was positive correlation ( r=0.7321, P <0.05), whereas the relation between the contents of MPA and the liquidity of erythrocytic membrane was negative correlation (r = -0.6438, P <0.01). The erythrocytio membrane liquidity decreased in milk goat with fluorosis, which played a role in the occurrence and development of the fluorosis. There was correlation among the erythrocytic membrane liquidity and the contents of MDA, the activity of SOD.  相似文献   
100.
本研究的目的是确定肥育阶段(体重为67至113 kg)的杂交猪对苏氨酸(Thr)需求量.试验期为50 d,30头阉割公猪和30头母猪用于此次试验.试验猪采食添加不同水平的苏氨酸处理日粮(粗蛋白:135g/kg,赖氨酸:8.0 g/kg).日粮中总苏氨酸含量(g/kg)分别为:4.9,5.0,5.4,5.8,6.1和6.5.其分别对应的苏氨酸与赖氨酸之比率约为0.60,0.64,0.68,0.73,0.76和0.81.试验结果表明,与基础日粮处理组相比,日粮中苏氨酸浓度为5.4g/kg时,日增重约提高15%(P<0.05),饲料转化率约提高7%.日粮中高于5.4g/kg的苏氨酸对猪生产性能没有进一步的影响.当日粮中苏氨酸含量为6.1 g/kg时,猪血浆中尿素浓度减少到最低水平.日粮处理对猪的胴体品质没有影响,并且对小肠和结肠上杯状细胞密度的影响也不存在差异.基于日增重的增长结果,日粮中最适苏氨酸与赖氨酸的比值范围应为0.66至0.68.  相似文献   
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