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31.
介绍了国内外高等级公路工程中应用SST固化剂施工的基本情况,着重介绍自行开发的改性SST固化剂的改性技术、机理分析、工艺要领与工程质量数据,并作出了技术经济评估。 相似文献
32.
Zhongping Chen D. L. Kaplan K. Yang J. Kumar K. A. Marx S. K. Tripathy 《Journal of Sol-Gel Science and Technology》1996,7(1-2):99-108
Light transducing phycobiliproteins are encapsulated in optically transparent sol-gel matrices. Absorption and fluorescence spectroscopies are used to characterize the effect of the sol-gel encapsulation on the conformation and aggregation states of the three major phycobiliproteins present in phycobilisomes: phycoerythrin, phycocyanin, and allophycocyanin. It is found that the effects of sol-gel entrapment on the spectroscopic properties are significantly different for the three phycobiliproteins. The results indicate that phycoerythrin undergoes only minor change in its native structure when entrapped in sol-gel. However, significant changes in conformation and aggregation state occur when phycocyanin and allophycocyanin are entrapped in sol-gel matrices. A thin film of sol-gel encapsulated phycoerythrin is also coated on an optical fiber surface and strong fluorescence from the evanescent wave excitation is detected. The potential applications of sol-gel encapsulated phycobiliproteins in biosensors are discussed. 相似文献
33.
In this work, we reformulate the inverse optimal value problem equivalently as a corresponding nonlinear bilevel programming (BLP) problem. For the nonlinear BLP problem, the duality gap of the lower level problem is appended to the upper level objective with a penalty, and then a penalized problem is obtained. On the basis of the concept of partial calmness, we prove that the penalty function is exact. Then, an algorithm is proposed and an inverse optimal value problem is resolved to illustrate the algorithm. 相似文献
34.
This article deals with the critical curve of a fast diffusive polytropic filtration system coupled at the boundary condition. By constructing the self-similar supersolution and subsolution, we obtain the critical global existence curve. The critical curve of Fujita type is conjectured with the aid of some new results. 相似文献
35.
In this article, we deal with the global existence and nonexistence of solutions to the non-Newtonian polytropic filtration equations coupled with nonlinear boundary conditions. By constructing various kinds of sub- and super-solutions and using the basic properties of M-matrix, we give the necessary and sufficient conditions for global existence of nonnegative solutions. The critical curve of Fujita type is conjectured with the aid of some new results, which extend the recent results of Zheng, Song, and Jiang [Critical Fujita exponents for degenerate parabolic equations coupled via nonlinear boundary flux, J. Math. Anal. Appl. 298 (2004), pp. 308–324], Zhou and Mu [Critical curve for a non-Newtonian polytropic filtration system coupled via nonlinear boundary flux, Nonlinear Anal. 68 (2008), pp. 1–11], and Zhou and Mu [Algebraic criteria for global existence or blow-up for a boundary coupled system of nonlinear diffusion equations, Appl. Anal. 86 (2007), pp. 1185–1197] to more general equations. 相似文献
36.
Zhongping Li Chunlai Mu Wanjuan Du 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2013,64(2):253-263
This paper deals with coupled nonlinear diffusion equations with absorptions. We characterize the range of parameters for which non-simultaneous blow up occurs. We establish the necessary and sufficient conditions for the occurrence of non-simultaneous blow up with proper initial data. Moreover, we obtain the optimal condition under which any blow up is non-simultaneous. 相似文献
37.
AbstractIn this article, a projection-type method for mixed variational inequalities is proposed in Hilbert spaces. The proposed method has the following nice features: (i) The algorithm is well defined whether the solution set of the problem is nonempty or not, under some mild assumptions; (ii) If the solution set is nonempty, then the sequence generated by the method is strongly convergent to the solution, which is closest to the initial point; (iii) The existence of the solutions to variational inequalities can be verified through the behavior of the generated sequence. The results presented in this article generalize and improve some known results. 相似文献
38.
Pan Ou Ruilong Zhang Zhengjie Liu Xiaohe Tian Guangmei Han Bianhua Liu Zhangjun Hu Zhongping Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(8):2283-2287
Enzyme activity in live cells is dynamically regulated by small‐molecule transmitters for maintaining normal physiological functions. A few probes have been devised to measure intracellular enzyme activities by fluorescent imaging, but the study of the regulation of enzyme activity via gasotransmitters in situ remains a long‐standing challenge. Herein, we report a three‐channel imaging correlation by a single dual‐reactive fluorescent probe to measure the dependence of phosphatase activity on the H2S level in cells. The two sites of the probe reactive to H2S and phosphatase individually produce blue and green fluorescent responses, respectively, and resonance energy transfer can be triggered by their coexistence. Fluorescent analysis based on the three‐channel imaging correlation shows that cells have an ideal level of H2S to promote phosphatase activity up to its maximum. Significantly, a slight deviation from this H2S level leads to a sharp decrease of phosphatase activity. The discovery further strengthens our understanding of the importance of H2S in cellular signaling and in various human diseases. 相似文献
39.
The aim of this work is to discuss the growth characteristics of the ceramic coatings on Ti alloy by plasma electrolytic oxidation (PEO) technique. Ceramic coatings were prepared on Ti alloy by plasma electrolytic oxidation in different electrolyte solutions under different pulse modes. The composition and the structure of the coatings were investigated by X-ray diffraction and scanning electron microscopy (SEM), respectively. The amount of the dissolved titanium into the electrolytes during PEO process was measured by inductively coupled plasma-atomic emission spectrometer (ICP-AES). The structure and the composition of the coatings were related to the mode of the spark discharge during PEO process. (a) Under the pulsed single-polar mode: In Na3PO4 solution, the spark discharge was mainly due to the breakdown of the oxide film, and the coatings prepared were porous and mainly structured by the Ti from the substrate. In K4ZrF6-H3PO4 and NaAlO2-Na3PO4 solutions, the main mode of the spark discharge was the breakdown of the oxide film at the initial stage, and then changed into the breakdown of the vapor envelope, and the coatings were rough and thick, and mainly structured by the elements from the electrolyte. (b) Under the pulsed bi-polar mode in NaAlO2-Na3PO4 solution, the spark discharge may be mainly due to the breakdown of the oxide film, the coatings prepared were dense in inner layer and loose in outer layer, and structured by the elements from both the substrate and the electrolyte. Besides, the ICP-AES analyses showed that the amount of the dissolved titanium in the electrolyte during PEO process was more under the breakdown of the oxide film than under the breakdown of the vapor envelope, which was consistent with the changes of the structure of the coatings. Cathode pulse in the pulsed bi-polar mode increased the amount of the dissolved titanium in the electrolyte, compared with the pulsed single-polar one. 相似文献
40.
Wang Zhongping Zhao Yating Zhou Long Xu Linglin Diao Guizhi Liu Guanghua 《Journal of Thermal Analysis and Calorimetry》2020,140(2):545-553
Journal of Thermal Analysis and Calorimetry - Aluminate containing phases such as tricalcium aluminate (C3A) and dodecacalcium heptaaluminate (C12A7) play a key role in the reaction between... 相似文献