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61.
Mesoporous glasses – the leaching products of phase‐separated alkali borosilicate glasses – are widely used in fundamental research and practical applications. In this work, the option to control their internal mesopore structure by varying the conditions of microphase separation has been studied. Structure and transport characterization of a family of nanoporous glasses obtained under different conditions has been performed using a combination of several experimental techniques, including gas adsorption, nuclear magnetic resonance cryoporometry and diffusometry.  相似文献   
62.
We have studied the temperature dependence of heat capacity for ZnTe at temperatures above 250 K. Based on analysis of the present and previous heat capacity data, we recommended the most reliable data in the temperature range 250–1000 K.  相似文献   
63.
In modern production and distribution systems, the automated storage/retrieval systems (AS/RS), high-storage level systems that reduce labor cost, required floor space and error rate, while increasing product availability, have been widely used since the 1950s. Due to the high-investment costs involved in the development of high-efficient and high-flexible automated storage systems, performance estimation of the systems is both practically and theoretically important. The authors suggest a new method to estimate the travel time of a recently emerging version of AS/RSs, the multi-shuttle systems. The proposal is based on an industrial standard established by the Federation Européenne de la Manutention (F.E.M.). In order to estimate travel times, the authors conduct a Monte Carlo simulation to determine coordinates of two additional representative points which are not given by F.E.M. Then they conduct a new Monte Carlo simulation to compare the results obtained by the method they proposed with those of previous methods and models developed in scientific literature based on Bozer and White formulations. Several real industrial applications demonstrate the validity of proposed method.  相似文献   
64.
The possibility of decreasing the combustibility of PCA and PETP fibres by treatment with acetone solutions of PVC containing tin oxides or salts was investigated. It was found that the PVC—ZnSn(OH)6 system is the most efficient fire-retardant system for PETP. The oxygen index of PETP after treatment with this system was 27.1%. It was shown that in contrast to other types of halogen—metal-containing fire retardants whose effect is basically manifested in the gas phase, the synergistic system containing PVC and tin-containing compounds changes the direction of the reactions in the condensed phase of combustion. The capacity of the polymer (PCA, PETP) for carbonization increases in the presence of PVC and tin-containing compounds as a result of the formation of thermostable structures characterized by a high concentration of halogen, and the temperature of the onset of oxidation decreases.Moscow State Textile Academy. Translated from Khimicheskie Volokna, No. 6, pp. 34–36, November–December, 1993.  相似文献   
65.
Regeneration of irradiated and actual spent solvent (30% TBP in a hydrocarbon diluent) by overheated steam distillation was studied in batch experiments. The hydrodynamic and extraction-backwash parameters of thus regenerated solvent are practically the same as those of the fresh solvent. The bottoms comprise 3-7% of the initial volume and consist essentially of TBP. Large-scale rig trials of the single- and two-step continuous processes of solvent distillation are performed. Single-step distillation with overheated steam in a vacuum or with saturated water vapor at atmospheric pressure provides transfer into the distillate of the whole amount of the solvent, permitting the use of any diluent. The two-step process allows separation of the solvent into the TBP and diluent fractions and refining of each of them in the case when the diluent boiling point is below that of TBP by 50-70°.  相似文献   
66.
Translated from Izmeritel'naya Tekhnika, No. 4, p. 14, April, 1989.  相似文献   
67.
Conclusions -- The effect of the method of preliminary heat treatment and of the structure of fibre being subjected to boronation on the strength of high-modulus carbon fibres has been shown.-- A moreoriented structure of the fibre subjected to boronation and stress relaxation during the heat-treatment process aid in bringing about an increase in strength of high-modulus carbon fibre up to 3.0–3.5 GPa at an elastic modulus greater than 700 GPa.All-Union Scientific Research and Project-Technological Institute of Electrical Carbon Articles, Élektrougli. Translated from Khimicheskie Volokna, No. 3, pp. 29–30, May–June, 1991.  相似文献   
68.
New possibilities of scanning electron microscopy, using secondary-and reflected-electron signals, for determining the position of heteroboundaries in long-wavelength laser structures are reported. The formation of the indicated signals in structures of mid-infrared-range lasers of a new type based on type-II GaInAsSb/InGaAsSb heterostructures as well as in the conventional InAsSb/InAsSbP heterostructures is analyzed. The observed characteristic features of the formation of secondary-and reflected-electron signals in these structures as compared with the well-studied AlGaAs/GaAs structures are explained. The results obtained are necessary for accurate determination of an important laser parameter — the position of the p-n junction. It is shown that it is best to use the reflected-electron signal. Fiz. Tekh. Poluprovodn. 32, 1300–1305 (November 1998)  相似文献   
69.
Over-claiming is a concrete operalization of self-enhancement based on respondents' ratings of their knowledge of various persons, events, products, and so on. Because 20% of the items are nonexistent, responses can be analyzed with signal detection formulas to index both response bias (over-claiming) and accuracy (knowledge). Study 1 demonstrated convergence of over-claiming with alternative measures of self-enhancement but independence from cognitive ability. In Studies 2-3, the validity of the over-claiming index held even when respondents were (a) warned about the foils or (b) asked to fake good. Study 3 also showed the utility of the over-claiming index for diagnosing faking. In Study 4, the over-claiming technique was applied to the debate over the adaptive value of positive illusions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
70.
A large group of prion‐associated proteins was identified in yeast cells using a new approach, comparative analysis of pellet proteins of crude cell lysates in isogenic strains of Saccharomyces cerevisiae differing by their prion composition. Two‐dimensional (2D) electrophoresis followed by MALDI analysis of the pellet proteins of [PSI+] and [psi?] strains after prion elimination by GuHCl and prion transmission by cytoduction permitted identification of ca. 40 proteins whose aggregation state correlated with the change of prion(s) content. Approximately half of these proteins belonged to chaperones and to enzymes of glucose metabolism. Chaperones are known to be involved in prion metabolism and are expected to be present in prion‐containing aggregates, but glucose metabolism enzymes are not predicted to be present. Nevertheless, several recent data suggest that their presence is not incidental. We detected six proteins involved in oxidative stress response and eight in translation. Also notable is a protease. Most of the identified proteins seem to be prion‐associated, but we cannot exclude the possibility that several proteins may propagate as prions. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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