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81.
High-index nanoparticles are known to support radiationless states called anapoles, where dipolar and toroidal moments interfere to inhibit scattering to the fa...  相似文献   
82.
Union International Contre le Cancer (U.I.C.C.) reference standard asbestos samples have been extracted with pentane and the organic material in the extract has been examined by gas chromatography. Mass spectrometry was used to provide supporting evidence of the presence of some components identified in the chromatograms.Ultraviolet and fluorescence spectra of the extracted oils indicated that polycyclic aromatic hydrocarbons were a minor constituent of the organic extract.More than sixty components were observed in each of the five pentane extracts. By far the greatest proportion of the extracted material was comprised of a homologous series of n-alkanes.  相似文献   
83.
A method for determining glaze penetration was developed and the effect of glaze penetration on glaze fit studied. The effects of twenty-four fluxes on penetration of a base glaze into semivitreous, hotel china, terra cotta, cordierite, pyrophyllite, wall tile, and steatite bodies were determined. The result shows that glaze penetration affects glaze fit and that penetration varies greatly, depending on glaze composition and the character of the body.  相似文献   
84.
Summary Urea complex formation has been employed in the preparation of purified oleic acid (oleic acid content, 80–95%) from various grades of inedible animal fats and red oils. Since the urea complex of oleic acid forms in good yield at room temperature, low temperatures are not required in the isolation procedure. Yields of oleic acid are equal to or lower than those obtained by conventional low-temperature crystallization procedures, but the preparation of a polyunsaturate-free oleic acid is apparently not possible by urea complex formation alone. The separation of polyunsaturated acids from oleic acid by urea complex formation is more convenient than but not as efficient as by solvent crystallization, but separation of saturated acids from unsaturated acids is less convenient. Advantages and disadvantages in using urea in the preparation of purified oleic acid are briefly discussed. Presented at the Spring Meeting of the American Oil Chemists' Society held in Houston, Tex., April 28–30, 1952. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration. U. S. Department of Agriculture.  相似文献   
85.
The possibility of applying Linear or Quadratic Programming to the problem of optimizing nuclear reactor fuel recycle, is investigated. It is demonstrated, that the methods mentioned, may be applied successfully to a simplified model of a nuclear reactor. An appropriate representation of the fuel recycle as a feedback control system is proposed. An iterative algorithm to establish the refueling times, which are unknown a priori, is formulated and implemented to some specific examples. The convergence of the algorithm, proposed in this paper, has been established numerically.  相似文献   
86.
The present study deals with a digital computer version of the method described in the previous theoretical part. The study describes program structure of the so-called procedure and provides guidance for its practical use. As illustration a problem associated with a chemical plant is disclosed, the size of which demonstrates vividly its performance.  相似文献   
87.
This is the May 1996 report of a subpanel of the US Department of Energy Fusion Energy Sciences Advisory Committee (FESAC), charged with conducting a review of the progress, priorities and potential near-term contributions of TFTR, DIII-D and Alcator C-MOD (and other facilities as appropriate) as part of the transition to a Fusion Energy Sciences Program and produce an optimum plan for obtaining the most scientific benefit from them.  相似文献   
88.
(1) Background: Placental immune cells are playing a very important role in a successful placentation and the prevention of pregnancy complications. Macrophages dominate in number and relevance in the maternal and the fetal part of the placenta. The evidence on the polarization state of fetal and maternal macrophages involved in both, healthy and pregnancy-associated diseases, is limited. There is no representative isolation method for the direct comparison of maternal and fetal macrophages so far. (2) Material and Methods: For the isolation of decidual macrophages and Hofbauer cells from term placenta, fresh tissue was mechanically dissected and digested with trypsin and collagenase A. Afterwards cell enrichment was increased by a Percoll gradient. CD68 is represented as pan-macrophage marker, the surface markers CD80 and CD163 were further investigated. (3) Results: The established method revealed a high cell yield and purity of the isolated macrophages and enabled the comparison between decidual macrophages and Hofbauer cells. No significant difference was observed in the percentage of single CD163+ cells in the distinct macrophage populations, by using FACS and immunofluorescence staining. A slight increase of CD80+ cells could be found in the decidual macrophages. Considering the percentage of CD80+CD163 and CD80CD163+ cells we could not find differences. Interestingly we found an increased number of double positive cells (CD80+CD163+) in the decidual macrophage population in comparison to Hofbauer cells. (4) Conclusion: In this study we demonstrate that our established isolation method enables the investigation of decidual macrophages and Hofbauer cells in the placenta. It represents a promising method for direct cell comparison, enzyme independently, and unaffected by magnetic beads, to understand the functional subsets of placental macrophages and to identify therapeutic targets of pregnancy associated diseases.  相似文献   
89.
90.
As a new field of oxidative stress-based therapy, cold physical plasma is a promising tool for several biomedical applications due to its potential to create a broad diversity of reactive oxygen and nitrogen species (RONS). Although proposed, the impact of plasma-derived RONS on the cell membrane lipids and properties is not fully understood. For this purpose, the changes in the lipid bilayer functionality under oxidative stress generated by an argon plasma jet (kINPen) were investigated by electrochemical techniques. In addition, liquid chromatography-tandem mass spectrometry was employed to analyze the plasma-induced modifications on the model lipids. Various asymmetric bilayers mimicking the structure and properties of the erythrocyte cell membrane were transferred onto a gold electrode surface by Langmuir-Blodgett/Langmuir-Schaefer deposition techniques. A strong impact of cholesterol on membrane permeabilization by plasma-derived species was revealed. Moreover, the maintenance of the barrier properties is influenced by the chemical composition of the head group. Mainly the head group size and its hydrogen bonding capacities are relevant, and phosphatidylcholines are significantly more susceptible than phosphatidylserines and other lipid classes, underlining the high relevance of this lipid class in membrane dynamics and cell physiology.  相似文献   
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