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71.
本文介绍了基于某些名、优农产品在其生长过程中所需要的特定敏感元素,配制出“仿土质”专用肥。经施用证明,肥效显著,经济效益可观,具有推广应用的前景。 相似文献
72.
Cu–dinitro–diamino phthalocyanine was synthesized and converted to the diazonium salt. Polyacrylamide bonded CuPc(NO2)2 [PAA–CuPc(NO2)2] (I) was synthesized by hot polymerization of acrylamide and this diazonium salt. Polymer(I) is water soluble and contains about 7 mol % CuPc(NO2)2 rings, which are covalently bonded to PAA. Polymer(I) shows good photoconductivity, which is much better than that of the corresponding phthalocyanine monomers. By doping with iodine (I2), the photosensitivity of polymer(I) is increased, which through fluorescence analysis is explained by the fact that a charge–transfer complex (CTC) of polymer(I) with I2 is formed. The influence of interface layer (IFL) and charge–transportation material (CTM) on the photoconductivity of polymer(I) were also studied. 相似文献
73.
74.
Tungsten oxide (WO3) nanorods array prepared using chemical vapor deposition techniques was studied. The influence of oxygen gas concentration
on the nanoscale tungsten oxide structure was observed; it was responsible for the stoichiometric and morphology variation
from nanoscale particle to nanorods array. Experimental results also indicated that the deposition temperature was highly
related to the morphology; the chemical structure, however, was stable. The evolution of the crystalline structure and surface
morphology was analyzed by scanning electron microscopy, Raman spectra and X-ray diffraction approaches. The stoichiometric
variation was indicated by energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. 相似文献
75.
In this paper, we propose a new hard problem, called bilateral inhomogeneous small integer solution (Bi-ISIS), which can be seen as an extension of the small integer solution problem on lattices. The main idea is that, instead of choosing a rectangle matrix, we choose a square matrix with small rank to generate Bi-ISIS problem without affecting the hardness of the underlying SIS problem. Based on this new problem, we present two new hardness problems: computational Bi-ISIS and decisional problems. As a direct application of these problems, we construct a new lattice-based key exchange (KE) protocol, which is analogous to the classic Diffie- Hellman KE protocol. We prove the security of this protocol and show that it provides better security in case of worst-case hardness of lattice problems, relatively efficient implementations, and great simplicity. 相似文献
76.
In this paper, the uplink and downlink performance of a two-tier heterogeneous network (HetNet) with range expansion (RE) is analyzed. Different from previous works, base stations (BSs) are modeled as a spatial Poisson point process. This model can not only capture the irregularity of the BS deployment but also lead to closed form expressions. With the analytical results, the impacts of several key parameters on the coverage and throughput performance are investigated. Our results justifies the effectiveness of RE and Pico deployment. Based on our analyses, certain attention should be made on the RE design to balance the uplink and downlink performance. Our analyses are corroborated by simulations and can thus serve as a flexible and quick guidance for system design without complicated and time-consuming system-level platform construction and simulation. 相似文献
77.
Considering the randomness or interval character of physical parameters and applied loads of composite pressure vessels (COPV), the COPV reliability-analyzing model is built. And then the computational expressions for the mean value, standard deviation and deviation of fiber stress are deduced by the random factor method. The probabilistic and interval reliability designs on COPV are implemented by utilizing the probabilistic method and interval method combined with the improved particle swarm optimization (PSO) algorithm, respectively. The influence of fluctuation of structure uncertain parameters on COPV design thickness is inspected. Finally, examples are given to demonstrate that both probabilistic and interval reliability methods can satisfy the safety requirement and both are of higher rationality than the traditional safety factor method. And probabilistic method has a lower relative error but a higher computational complexity contrasted with the interval method. 相似文献
78.
充分发挥市场机制对节能产品的调控作用是市场经济的基本内容。通过对建筑节能市场发展中存在的相关问题研究,发现我国建筑节能市场的外部性和信息不对称性是产生问题的根源。全面分析建筑节能市场中政府、开发商、消费者以及其他服务组织等利益主体对市场培育的核心作用,通过构建政府与开发商、开发商与消费者之间的动态博弈模型,研究相关利益主体进一步完善建筑节能市场应采取的对策。 相似文献
79.
高校图书馆在参与支持“农家书屋”的建设与发展中具有专业技术人才、信息资源等优势,可以通过对“农家书屋”管理员进行图书情报业务培训、协助“农家书屋”制定管理制度与开发自动化管理软件、组织高校教职工及大学生捐献图书与声像资料、组织大学生寒暑假“三下乡”和建设高校“读者协会”的社会实践基地来推动“农家书屋”的健康发展. 相似文献
80.
针对我国当前网络政治参与中存在着非法参与行为多、政务信息不公开致使公众政治参与缺乏信息基础、政府对公众网络政治参与的行为与观点缺乏回应等问题,本文提出了采取完善政治参与和网络政治参与的法治化机制,建立健全网络参政相关法规,保障公民网络参政议政权益,规范和打击非法政治参与行为;修改政府信息公开的法律法规,加大政府信息公开力度与规范网络监督机制;建立政府对公民网络政治参与的回应制度,以解决公民网络政治参与的相关问题,推动法治文明. 相似文献