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排序方式: 共有1797条查询结果,搜索用时 31 毫秒
1.
The paper concerns an analysis of an equilibrium problem for 2D elastic body with two semirigid inclusions. It is assumed that inclusions have a joint point, and we investigate a junction problem for these inclusions. The existence of solutions is proved, and different equivalent formulations of the problem are proposed. We investigate a convergence to infinity of a rigidity parameter of the semirigid inclusion. It is proved that in the limit, we obtain an equilibrium problem for the elastic body with a rigid inclusion and a semirigid one. A parameter identification problem is investigated. In particular, the existence of a solution to a suitable optimal control problem is proved. 相似文献
2.
V. I. Fedorov S. S. Popova A. N. Pisarchik 《Journal of Infrared, Millimeter and Terahertz Waves》2003,24(8):1235-1254
We have presented an overview of the literature and of our experimental data on the influence of electromagnetic radiation in the submillimeter spectral region on biological objects of molecular, cellular, and organism levels. Possible physical mechanisms involved and the reasons for limited development of the research in this spectral range are discussed. 相似文献
3.
O. Yu. Alekseev V. S. Borisov M. V. Davidovich N. F. Popova 《Journal of Communications Technology and Electronics》2006,51(11):1240-1247
Direct and inverse problems are considered for diffraction by an open end of a rectangular waveguide (RW) with a flange that adjoins a piecewise inhomogeneous planar layered lossy medium. Also considered are similar diffraction problems for a junction of an RW and a rectangular resonator filled with a multilayer medium and a junction of two RWs, one of which contains a multilayer plate. Such open and shielded waveguide probe structures (WPSs) are used for determination and nondestructive testing of parameters of multilayer samples. The direct problem is formulated on the basis of admittance and impedance algorithms with consideration for losses existing in the medium, flange, and screens. In this case, the approximation of the given aperture field allows obtainment of explicit solutions for open and shielded WPSs in the form of integrals. Solution of the inverse problem that lies in determining thicknesses, permittivities, and permeabilities of the layers from measured values of the magnitude of the reflection coefficient is obtained by minimizing the corresponding least-squares error and by constructing artificial neural networks. In order to increase the accuracy, it is proposed to use a two-port of errors and perform measurements for several positions of the sample with respect to the flange and different impedance conditions behind the sample. 相似文献
4.
SA Khotimchenko VM Kodentsova IA Alekseeva SG Vlaskina OA Vrzhesinskaia AA Sokol''nikov LA Kharitonchik IP Aleshko-Ozhevskií LV Sheviakova 《Canadian Metallurgical Quarterly》1997,43(3):158-164
Gamma delta T-Cells represent a minor subpopulation of T-lymphocytes in man and their role in normal and diseased human skin is unknown. This article is a comprehensive review of T-lymphocytes bearing the gamma delta T-cell receptor in normal and pathological human skin. Firstly, we have documented the occurrence of gamma delta T-cells in normal skin and in a range of reactive and malignant skin conditions. We have then discussed the experimental findings regarding the repertoire used by gamma delta T-cells in normal human skin and in cutaneous disorders with an increased percentage of gamma delta T-cells. 相似文献
5.
N. A. Sivov A. I. Martynenko G. N. Bondarenko M. P. Filatova E. Yu. Kabanova N. I. Popova A. N. Sivov E. B. Kruts’ko 《Petroleum Chemistry》2006,46(1):41-59
Structures and compositions of the monomers guanidine acrylate and guanidine methacrylate, their homopolymers, and copolymers with diallyldimethylammonium chloride enriched in acrylate comonomer units were determined. It was shown that ampholytic copolymers, owing to their ionic nature, contained comonomeric guanidine acrylate or methacrylate units and diallyldimethylammonium chloride units, as well as the acrylate comonomer with the diallyl counterion and polymeric acrylate and diallyl ion pairs. It follows from IR and 1H NMR data that guanidine methacrylate has the same structure (with two hydrogen bonds) in the solid state and in solutions. Guanidine acrylate structures in the solid state and in dimethylsulfoxide are identical and analogous to guanidine methacrylate structure in this solvent. In water, the guanidine acrylate structure has another type of hydrogen bonding (with one hydrogen bond, where the proton is shifted toward the guanidine group). These features of hydrogen bonding of guanidine acrylate and guanidine methacrylate are also retained in their homopolymers and copolymers with diallyldimethylammonium chloride. It was shown that the thermal stability of the copolymers was higher than that of their homopolymers, confirming the formation of intramolecular ion pairs of oppositely charged units of ampholytic copolymers. Moreover, the thermal stability of guanidine methacrylate-diallyldimethylammonium chloride copolymers is higher than that of guanidine acrylate-diallyldimethylammonium chloride copolymers. 相似文献
6.
7.
Although thoracoabdominal injuries are uncommon in the athlete, they can be catastrophic if unrecognized or if diagnosis and treatment are delayed. This article reviews thoracic, intrathoracic, abdominal, and groin injuries in the athlete, and how they can be diagnosed and managed. 相似文献
8.
AA Bakova BD Brondz OA Fedorkina VA Gusev AI Gordienko IuS Krivoshein IuL Krivorutchenko TG Prokopenko IA Popov 《Canadian Metallurgical Quarterly》1994,39(4):187-189
The possibilities of using influenza A (Leningrad) 385/80 (H3N2) virus matrix protein-specific FITC-labeled D8 monoclonal antibodies in immunofluorescence assays were investigated. The virus antigen accumulation was detected in chorioallantoic cells of chick embryos. Exhibiting the type-specific properties, the fluorescent antibodies stain the perinuclear space, cytoplasmic membrane, and granular structures in the cytoplasm of infected cells. The haemagglutination test tires in the corresponding specimens were at least 1:16. 相似文献
9.
II Kalachev AN Baídus' OA Ivanova EA Ganina IA Boldyrev EA Svetoch 《Canadian Metallurgical Quarterly》1997,(6):32-37
Unlike the glanders agent, the superficial structures of the melioidosis agent were demonstrated to be responsible for marked was immunosuppressive activity. Some antigenic fractions suppressing the blast transformation of lymphocytes, reducing the count of T helpers and profoundly potentiating the infection in vivo were isolated from P. pseudomallei cells. The immunogenic and immunosuppressive activities of both agents' superficial structures were studied by high performance chromatography. Antigenic complexes that were able to protect immunized laboratory animals against fatal infections and to prevent bacterial carriage due to the activation of T cells and to the bacterial activity of macrophages were identified. A composition comprising several immunogens was found to provide an additive protective action against both causative agents. Therefore, the composition may be considered to be a prototype of a molecular antipseudomonadic vaccine. 相似文献
10.
The monoclonal antibody CD 68 (KP 1) reacts with fibrohistiocytic and some epithelial neoplasms; its reactivity compared with that of HMB 45 in malignant melanoma (MM) and neural tumors needs further elucidation. Using a streptavidin-biotin-immunoperoxidase procedure, we examined the reactivity of 65 MM (46 conventional, 1 polypoid, 6 desmoplastic [DMM], and 12 metastatic), 21 neurofibromas, 1 neurofibrosarcoma, 10 schwannomas, 1 perineurioma, 2 neurothekeomas, and 14 blue and 26 other nevi for CD-68, HMB-45-defined antigen, S 100 and neurofilament protein. A positive staining for CD 68 was observed in 38 of 42 primary, 5 of 6 DMM, and 11 of 12 metastatic melanomas; 6 of 10 schwannomas; 5 of 10 nevi with junctional component and all 14 blue nevi. All 21 neurofibromas, 1 each neurofibrosarcoma and perineurioma, both neurothekeomas, and all 12 nevi with dermal component were CD 68-negative. HBM 45 was expressed by all 44 primary, none of 6 DMM, and 7 of 12 metastatic melanomas; by none of 10 schwannomas, 6 neurofibromas, 1 neurofibrosarcoma, 1 perineurioma and 2 neurothekeomas. Both junctional nevi, 8 of 10 nevi with junctional components, 1 of 10 dermal components of junctional nevi, and 11 of 13 blue nevi were also HMB 45 positive. Except for 1 perineurioma, S 100 decorated all tumors examined. NF was immunoreactive in 1 of 45 conventional melanomas, 2 of 21 neurofibromas, 2 of 10 schwannomas, and 3 of 10 blue nevi; it was non-reactive in all polypoid, desmoplastic and metastatic melanomas; neurofibrosarcoma, perineurioma, neurothekeoma and other nevi. We conclude that the CD-68-reactivity in primary melanomas, neurofibromas, neurofibrosarcomas, perineuriomas, and nevi was similar to that of HMB 45. The significantly higher CD 68-positivity than of HMB 45 in metastatic and desmoplastic melanomas and schwannomas may be of diagnostic value. 相似文献