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1.
Several aspects of the conditional equation derived from the accumulative equation are discussed in detail. The results indicate that the conditional equation not only is well consistent with the principles of electronegativity and absolute hardness equalization, but also satisfies the bonding of a full -prerequisite condition, e. g. two like electronic charge species repel and unlike attract each other'. In addition these principles are in the accumulative state. Mathematically, some other aspects of the conditional equation are worth studying based on the generalization of this equation.  相似文献   
2.
郑丽果  魏海安  张春燕 《安徽农业科学》2007,35(13):4046-4046,4079
在分析我国高等教育收费改革与现状的基础上,重点探讨了我国高等教育收费对农村生产和农民消费的影响.  相似文献   
3.
在分析当前我国农村税费改革存在的四大主要问题的基础上,有针对性地提出了政策建议和主张。  相似文献   
4.
Dielectric barrier discharge (DBD) can produce homogenous discharge in normal temperature and atomsphere with low energy consumption, so it has broad development prospects in industrial applications. An experimental study is carried out to optimize the needles arrangement and supply parameters aiming at the multineedle-to-cylinder reactor with orthogonal design in combination with Lissajous figures. As it is konwn, the process of discharge is also the process of charge transfer; hence, the more charges are transported, the higher reaction efficiency in plasma is. The orthogonal design is established with transported charges as the goal factor, and supply voltage, supply frequency, needles length(NL), interneedle rotation angles(INRA) as factors. Variance analysis results show that the largest influence factor is supply voltage, followed by supply frequency; the electrode configuration of NL=(3.5+2) mm and INRA=45° matched with f=21 kHz makes transported charges per cycle biggest. The orthogonal experiment results are verified by further experiments, which is significant to improve the DBD plasma reaction efficiency.  相似文献   
5.
针对农村税改后农业基础设施面临的新形势,详细分析了机遇和挑战;指出税改前后农村基础设施建设成果与存在问题;提出后税费改革时期农村基础设施建设的基本思路——落实科学发展观,坚持以人为本,改善农村交通、资讯、教育、能源、饮水、防洪和防灾减灾设施等;通过上述的分析,探讨了加快农村基础设施建设的对策建议,使基础设施建设投入与收益进入良性循环阶段。  相似文献   
6.
由点电荷在空间激发电场的电位公式,用两种不同的方法求出了均匀带电圆盘电位的空间分布。  相似文献   
7.
蚕丝蛋白在不同pH介质中的带电荷数对蚕丝织物染色、接枝改性等具有重要影响。采用蚕丝蛋白中极性氨基酸残基的电离常数计算了家蚕丝素蛋白、丝胶蛋白和柞蚕丝素蛋白所带电荷数与介质pH变化的关系,并通过测定蚕丝蛋白带电荷数与其丝绸试样对阴离子染料(活性艳蓝X-BR 140%)和十六烷基三甲铵吸附量的变化进行了验证。结果表明:家蚕丝素蛋白和丝胶蛋白在pH1~3时带正电荷、pH4~14时带负电荷,柞蚕丝素蛋白在pH1~4时带正电荷、pH5~14时带负电荷,家蚕丝素蛋白、丝胶蛋白和柞蚕丝素蛋白的等电点分别为3.6、3.3、4.2;家蚕丝素蛋白和丝胶蛋白的电荷急剧变化的区域在pH3~5和pH9~11,柞蚕丝素蛋白的电荷急剧变化的区域在pH2~4和pH9~11;家蚕和柞蚕丝蛋白在不同带电荷数时对阴离子染料和十六烷基三甲铵吸附量的实验值和理论值基本一致,蚕丝蛋白带电荷数随pH变化的理论计算结果可靠。  相似文献   
8.
Charging farmers for irrigation water is generally believed to lead to a more efficient water use. This paper contrasts measured irrigation efficiencies with characteristics of charges and irrigation systems. It discusses, for instance, the relation of field data with the generally endorsed presumption that water charges only influence irrigation efficiency if they are levied by volume.  相似文献   
9.
The functioning of 19 Users' Associations(UA's) in the Tunuyan region was evaluatedon the basis of an 85-questionquestionnaire and related interviews. The collectedinformation indicates that the management know-how of the UA'sis not appropriate for the new tasks involved in managing thelarger command areas(average 4000 ha). For a UA to be able tomaintain and modernize the irrigationsystem, sufficient funds must be available.For this to occur, the fee collection ratiomust be as high as practical. In thiscontext we conclude that an up-to-datewater users register is needed to chargethe actual user with the correct fee.Participation of farmers in the UAdecreases sharply with increase infarm size. Some of the contacts betweenfarmers and the UA are related to farmerknowledge of on-farm irrigation technology.Strangely, no formal training for on-farmirrigation is available in the region. TheUA's should join forces in providingextension to the farmers. This could reducethe number of reported conflicts(misunderstandings) between the UA and, inparticular, the small (and relatively lowskilled) farmers.  相似文献   
10.
The cost of irrigation water to the farmers in Mendoza Province consists of three components; canal cleaning by the farmer, a water charge to their Users Association (UA) and a water charge to the provincial Irrigation Department (DGI). The total cost of irrigation water shows large differences when the area of the UA is taken into consideration: farmers in smaller associations pay considerably more than those in large units. This is the case for all three groups of costs. The annual budgets of 31 UA's were analyzed with respect to 19 budget items prescribed by DGI. Several of these items contain a low percentage of the total budget. Further, they make participation of users during the annual meeting in which the budget is discussed and approved unnecessary difficult. We recommend to reduce the number of budget items to 7. Because of low collection levels (average 64%) the UA's spend a major part of their income on recurrent costs like salaries. As a result little is spent on maintenance and improvement of the system, creating dissatisfaction with the paying water users. Thus. a vicious circle needs to be broken about the deterioration of the system, dissatisfaction of users, less participation in the running of the Association and further deterioration. Recent experience shows that the discontinuation of flow to non-paying users in combination with improved water delivery services by the UA breaks the circle.  相似文献   
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