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21.
借鉴英国经验完善中国土地产权流转 总被引:1,自引:0,他引:1
本文在简要介绍中、英两国土地产权制度和土地产权流转的基础上,分析了我国土地产权流转过程中出现的问题,如征地过程中的赔偿过低且不完善、国有土地拆迁补偿不公以及补偿的分配方式不公平等问题。由于英国在土地制度方面与中国的相似性,文章借鉴英国土地补偿中的补偿金与改善金相结合原则、土地使用权的租赁行为以及开发收益回馈社会的方法,为完善和健全我国的土地产权流转机制提出措施和建议。 相似文献
22.
The authors used visual search tasks in which components of the classic flanker task (B. A. Eriksen & C. W. Eriksen, 1974) were introduced. In several experiments the authors obtained evidence of parallel search for a target among distractor elements. Therefore, 2-stage models of visual search predict no effect of the identity of those distractors. However, clear compatibility effects of the distractors were obtained: Responses were faster when the distractors were compatible with the response than when they were incompatible. These results show that even in parallel search tasks identity information is extracted from the distractors. In addition, alternative interpretations of the results in terms of the occasional identification of a distractor before or after the target was identified could be ruled out. The results showed that flat search slopes obtained in visual search experiments provide no benchmark for preattentive processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
23.
电力系统微机型产品的电磁兼容设计 总被引:2,自引:1,他引:1
从分析电力系统中电磁干扰的来源、传输途径入手,对应用于电力系统的微机型产品设计中的电磁兼容问题进行了较为系统的探讨,并提出了行有效的解决措施。 相似文献
24.
Fractionation of partly hydrolysed polyvinyl acetate (PVA) was performed by warming of its aqueous solutions. The following properties of the obtained fractions were determined: viscosity, molecular weight and molecular weight distribution, surface tension, and absorbance in the IR range. The blockiness of the polymer molecules, characterized by their behaviour towards iodine-containing systems such as I2,-H3BO3 and I2,-KI, was estimated. Fractionation of the aqueous solutions of PVA by warming is based mainly on the different internal molecular structure of the separated products, i.e. on the length of the vinyl acetate blocks in the PVA molecules and, to a lesser extent, on the degree of hydrolysis and the degree of polymerization. The more blocklike are the PVA molecules, the less compatible are the polymers in the PVA-hydroxypropyl methylcellulose (HPMC)-water system. At phase separation in this sytem the PVA molecules which are not compatible with HPMC are, in the first place, those of the highest blockiness. 相似文献
25.
HPVC/PP共混改性研究:Ⅲ低分子量反应性化合物作相容剂 总被引:3,自引:0,他引:3
采用低分子量反应性化合物作相容剂,即化学交联体系来改善HPVC/PP共混物的相容性。考察了在不同共混比下,不同化学交联体系对共混物力学性能的影响,并观察了共混物的微观形态。结果表明,采用低分子量反应性化合物作相容剂,共混物的拉伸强度提高,但冲击强度无改善。分散相尺寸减小,相间粘接得到改善。并比较了3种增容方法的效果,发现CPE是HPVC/PP共混物的最佳相容剂。 相似文献
26.
Flory's equation-of-state theory has been used to predict the lower critical solution temperature behaviour of polymer—polymer mixtures. The spinodal phase boundary of numbers of high molecular weight polymer mixtures have been previously simulated using this theory. In this paper a procedure for simultaneous predictions of the binodal and the spinodal curves by equating the chemical potential of each component in the mixture is presented. The method is tested for five different mixtures. The effects of the binary and pure component state parameters on the simulated curves are discussed and the simulated phase diagrams are compared with the experimental cloud point curves. It is found that in most cases the results are more consistent with the cloud point curve being closer to the spinodal curve than the binodal. 相似文献
27.
Fundamentals of stability testing 总被引:1,自引:0,他引:1
JOHN S. CANNELL 《International journal of cosmetic science》1985,7(6):291-303
The principles on which stability tests are based are reviewed. The need to differentiate between product stability and product-container compatibility is emphasized. Recognition of this distinction is fundamental to the efficient organisation and execution of stability tests.
Attention is also drawn to the desirability of having for every product a release specification with which it must comply when manufactured and a broader check specification with which it must comply throughout its shelf-life.
Test methods and the interpretation of the data accrued throughout a test are also discussed.
It is concluded that stability tests should not be conducted in accordance with a standardized routine pattern but that the objectives of each test should be defined and the test designed to achieve those objectives in the most efficient way.
Les regles fondamentales des essais de stabilite 相似文献
Attention is also drawn to the desirability of having for every product a release specification with which it must comply when manufactured and a broader check specification with which it must comply throughout its shelf-life.
Test methods and the interpretation of the data accrued throughout a test are also discussed.
It is concluded that stability tests should not be conducted in accordance with a standardized routine pattern but that the objectives of each test should be defined and the test designed to achieve those objectives in the most efficient way.
Les regles fondamentales des essais de stabilite 相似文献
28.
Simulation of water and nitrogen dynamics in soils during wastewater applications by using a finite-element model 总被引:4,自引:0,他引:4
Vassilis Z. Antonopoulos 《Water Resources Management》1993,7(3):237-251
A mathematical model was developed to simulate water movement, mass transport, and nitrogen transformations in soils during wastewater applications. The model is one-dimensional and based on the Galerkin finite-element method. The submodel of mass transport of nitrogen incorporates the convection-dispersion processes of ammonium and nitrate nitrogen, nitrification, denitrification, ammonium exchange and uptake of ammonium and nitrate ions. The accuracy and validity of the proposed model was examined by comparison with an explicit-implicit finite-difference model results. The model was used for simulation of water and nitrogen dynamics during wastewater application in homogeneous and multi-layered soils under different N concentration, rate, duration and scheduling of application. 相似文献
29.
面向表面组装工艺技术的PCB焊盘设计 总被引:1,自引:1,他引:0
尽管电子设计类软件已相当先进和方便,而且更新速度也很快,但是仍然无法满足各个层次的设计人员的需求,特别是适合各种元素封装形式的焊盘设计库并不能让设计和制造者满意,为了在此方面对PCB设计有所帮助,从印制电路板焊盘的设计方法入手,针对表面组装工艺技术特点,分析了PCB焊盘对PCA可靠性的影响因素,并根据相关的质量要求提出了较为简便的设计方案。 相似文献
30.
盐家油田油水井结垢原因探讨 总被引:2,自引:0,他引:2
对地层温度65~75℃的盐家油田油水井近井地带、井底、井筒发生严重结垢的原因进行了分析探讨。7口油井采出的地层水均为NaCO3型水.矿化度6.4~10g/L,HCO3浓度高(1.6~3.7g/L),Ca^2++Mg^2+浓度较低;1口水源井水及1口水井注入水为CaCl2型水,矿化度32~33g/L,Ca^2++Mg^2+浓度高(3.1~3.8g/L)而HCO3浓度低;采用CaCO3饱和指数法和CaSO4热力学溶解度法预测,在70℃下所有水样均有CaCO3结垢趋势,除3口油井采出的地层水外,均有CaSO4结垢趋势。3口油井采出的地层水与水源水在25℃按不同比例混合后,悬浮物含量大幅度上升。在70℃放置7天后再次大幅度上升,烘干的悬浮物易溶于稀盐酸.其主要成分为碳酸盐.说明注入水、地层水不配伍。1口电泵采油井和1口注水井油管垢样含盐酸可溶物(碳酸盐)超过90%。讨论了碳酸盐、硫酸盐垢的生成条件:温度、压力及pH值。图1表4参3。 相似文献