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11.
不同功能单体对分子印迹聚合物识别性能的模拟 总被引:1,自引:0,他引:1
以槲皮素为模板分子,以甲基丙烯酸(MAA)、三氟甲基丙烯酸(TFMAA)、丙烯酰胺(AM)、N-乙烯基吡咯烷酮(NVP)、2-乙烯基吡啶(2-VP)、4-乙烯基吡啶(4-VP)六种物质分别作为功能单体,运用量子化学方法模拟模板分子与不同功能单体的分子印迹聚合物预组装体系的构型、能量及复合反应的结合能△E,以讨论不同功能单体对分子印迹聚合物识别性能的影响,结果4-VP的印迹效应最好.通过模拟,有助于解释实验现象以及选择印迹效应更好的功能单体. 相似文献
12.
Applied Intelligence - The henry gas solubility optimization (HGSO) is a new nature-inspired algorithm that mimics Henry Gas Solubility to solve global optimization problems. The main changes of... 相似文献
13.
Ke Wang Baodan Liu Jing Li Xiaoyuan Liu Yang Zhou Xinglai Zhang Xiaoguo Bi Xin Jiang 《材料科学技术学报》2019,35(4):615-622
TiO_2 nanostructures with strong interfacial adhesion and diverse morphologies have been in-situ grown on Ti foil substrate through a multiple-step method based on conventional plasma electrolytic oxidation(PEO) technology, hydrothermal reaction and ion exchange process. The PEO process is critical to the formation of TiO_2 seeding layer for the nucleation of Na_2Ti_3O_7 and H_2Ti_3O_7 mediates that are strongly attached to the Ti foil. An ion exchange reaction can finally lead to the formation of H_2Ti_3O_7 nanostructures with diverse morphologies and the calcination process can turn the H_2Ti_3O_7 nanostructures into TiO_2 nanostructures with enhanced crystallinity. The morphology of the TiO_2 nanostructures including nanoparticles(NP), nanowhiskers(NWK), nanowires(NW) and nanosheets(NS) can be easily tailored by controlling the NaOH concentration and reaction time during hydrothermal process. The morphology, composition and optical properties of TiO_2 photocatalysts were analyzed using scanning electron microscope(SEM), X-ray diffraction(XRD), photoluminescence(PL) spectroscopy and UV–vis absorption spectrum. Photocatalytic tests indicate that the TiO_2 nanosheets calcined at 500?C show good crystallization and the best capability of decomposing organic pollutants. The decoration of Ag cocatalyst can further improve the photocatalytic performance of the TiO_2 nanosheets as a result of the enhanced charger separation efficiency. Cyclic photocatalytic test using TiO_2 nanostructures grown on Ti foil substrate demonstrates the superior stability in the photodegradation of organic pollutant, suggesting the promising potential of in-situ growth technology for industrial application. 相似文献
14.
Z. Y. Ma J. H. Li S. X. Li X. G. Ning Y. X. Lu J. Bi 《Journal of Materials Science》1996,31(3):741-747
The in situ formed Al2O3, TiB2 and Al3Ti mixture-reinforced aluminium composites were successfully fabricated by the reaction sintering of the TiO2-B-Al system in a vacuum. With increasing boron content in the TiO2-B-Al system, the amount of generated TiB2 in the composites increased and Al3Ti content decreased. At the same time the distribution uniformity of the in situ formed Al2O3 and TiB2 particulates was obviously improved, and the size of the Al3Ti particles was reduced. The in situ Al2O3 and TiB2 particulates had sizes from 0.096–1.88 m. The interface between the in situ formed particulates and the aluminium matrix was clean, and no consistent crystallographic orientation relationship was found. The strength and elastic modulus of the composites was significantly improved by lowering the Al3Ti content. When the boron content in the TiO2-B-Al system rose, the morphology of the tensile fracture surface of the composites was changed from large fractured Al3Ti blocks and fine dimples, to fine dimples and pulled-out particulates. The strengthening and fracture of the composites have been modelled. 相似文献
15.
基于蚁群算法的网格资源发现模型研究 总被引:1,自引:0,他引:1
本文通过对传统的网格资源发现存在的问题进行分析,针对其不足,引入蚁群算法,提出基于蚁群算法的网格资源发现模型(AA_GRRM),设计并分析AA_GRRM的体系结构,并对其关键模块分析设计,以提高网格资源发现效率。 相似文献
16.
Phase unwrapping is a key step in retrieving digital elevation models (DEMs) from across-track interferometric synthetic aperture radar (InSAR) data. The coherence of synthetic aperture radar (SAR) data set is an effective indicator for the quality of phase unwrapping. However, the coherence of different regions usually distributes unevenly in SAR images monitoring heterogeneous areas. Errors in low-coherence areas are prone to pollute the whole image. In order to mitigate propagation error, a new phase unwrapping algorithm based on region recognition and region expansion is proposed. In the region recognition step, optical images are incorporated to recognize low-coherence regions by virtue of supervised classification technique. Low-coherence regions and the ones that are not of interest for the application are then discarded. In the region expansion step, stable pixels of high coherence are selected as growing seeds, and then phase unwrapping grows from high-quality regions to low-quality ones guided by coherence information and weighted numbers of neighbouring unwrapped pixels. The ambiguity number of a wrapped pixel is estimated from its neighbouring pixels under the criteria of pixel distance and phase gradient. Iterative examination continues until the whole image is unwrapped. Experiments on PALSAR and ASAR data demonstrate its validity and advantages over other classical methods. 相似文献
17.
多层次弹性养老保障制度探讨 总被引:1,自引:0,他引:1
毕小龙 《武汉理工大学学报(信息与管理工程版)》2006,28(9):102-105
建立多层次弹性养老保障制度可以分散和降低人口老龄化带来的养老风险。针对我国社会养老保险制度所面临的严峻的人口老龄化挑战,分析了现行社会养老保险制度的缺陷;提出了包括一个救助层、两个强制层、一个补充层和一个自助层的五层次弹性养老保障制度模型。 相似文献
18.
以传递和扭矩和工作转速为设计条件,推导并建立了空气离心式离合器的承载能力方程式及其求解方法,并在此基础上提出了确定该种离合器主要结构参数的具体设计方法和步骤。使其更便于在实际中推广和应用。 相似文献
19.
The problem of stabilizing multiple independent linear systems sharing one conmmon network cable is presented and solved. Both the quanfization and time sequencing are studied in the field of control over networks by providing the formulated stabilizing sufficient condition which illustrates the relationship between the system instability, quanfization and time sequencing, and the data rate is also presented in temps of the quanfization and time sequencing. A numerical example is given to illustrate the result. 相似文献
20.
奥里油在火力发电厂的应用及环保处理 总被引:2,自引:0,他引:2
委内瑞拉富藏奥里油约469亿t,中国政府与委内瑞拉政府签订了合作生产并每年向中国供应650万t奥里油的合作协议。鉴于此,介绍了奥里油的特性及其在火力发电厂的应用情况,分析了燃烧奥里油发电带来的特有的环保问题和处理方法。 相似文献