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991.
Pb1–x
Ca
x
[(Co0.5W0.5)0·05Ti0.95]O3 ceramics with x = 0.24, 0.30 and 0.35, are prepared by a solid state reaction of oxides. Deviations from nominal chemical compositions and formation of segregated phases different from modified lead titanate perovskites, are studied. Pyro- and non-pyroelectric currents excited in the material by a thermal wave are investigated and related to mobility of electrical charges in the materials. 相似文献
992.
993.
V. V. Ruzhyts’kyi H. D. Tolstoluts’ka S. O. Karpov I. E. Kopanets’ H. M. Malyk 《Materials Science》2007,43(5):735-741
By the methods of thermal-desorption spectrometry and nuclear reactions, we study the processes of trapping, thermal desorption,
and evolution of the profiles of distribution of deuterium ionically implanted with an energy of 12 keV into Kh18N10T steel
at room temperature. The evolution of the microstructure of steel under the conditions of irradiation of samples with D2+ ions up to doses of 1 · 1018 D/m2−2 · 1022 D/m2 is studied by the method of electron microscopy. The regularities of changes in the mechanical properties of steel after
irradiation are determined.
__________
Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 5, pp. 117–121, September–October, 2007. 相似文献
994.
This paper deals with an economic comparison between costs and incomes in small wastewater treatment plants where the anaerobic co-digestion process of sludge and biowaste with energy recovery is operated. Plants in the size range 1,000-30,000 persons equivalent (pe) were considered in the study: typical costs, comprehensive of capital and operating costs, were in the range euro69-105 per person per year depending on the plant size: the smaller the size the higher the specific cost. The incomes deriving from taxes and fees for wastewater treatment are generally in the range euro36-54 per person per year and can only partially cover costs in small wastewater treatment plants. However, the co-treatment of biowaste and the use of produced energy for extra credits (green certificates) determine a clear improvement in the possible revenues from the plant. These were calculated to be euro23-25 per person per year; as a consequence the costs and incomes can be considered comparable for wastewater treatment plants (WWTPs) with size larger than 10,000 pe. Therefore, anaerobic co-digestion of biowaste and sludge can also be considered a sustainable solution for small wastewater treatment plants in rural areas where several different kinds of biowaste are available to enhance biogas production in anaerobic reactors. 相似文献
995.
996.
Existing NASA supported scientific databases are usually developed and managed by a team of database administrators whose main concern is the efficiency of the databases in terms of normalization and data search constructs. The populating of the database is usually done in a manual fashion by row and column as the data become available, and the data dictionary is usually defined by the same team (at times with little input from the end science user). This process is tedious, error prone and self-limiting in terms of what can be described in a relational Data Base Management System (DBMS). The next generation Earth remote sensing platforms [i.e., Earth Observing System (EOS)] will be capable of generating data at a rate of over 300 Megabits per second from a suite of instruments designed for different applications. What is needed is an innovative approach that creates object-oriented data-bases that segment, characterize, and catalog, and are manageable in a domain-specific context, and whose contents are available interactively and in near-real-time to the user community. This paper describes work in progress that utilizes an artificial neural net approach to characterize satellite imagery of undefined objects into high-level data objects. The characterized data is then dynamically allocated to an object-oriented database where it can be reviewed and accessed by a user. The definition, development, and evolution of the overall data system model are steps in the creation of an application-driven knowledge-based scientific information system. 相似文献
997.
998.
Shikimate dehydrogenase (E.C.1.1.1.25), extracted from heart-of-palm, was purified by precipitation with ammonium sulphate and elution from columns of Sephadex G-25, and DEAE-Sephadex A-50. The enzyme was unstable and it was not possible to maintain the activity by the addition of cysteine and 2-mercaptoethanol to the buffer. The heart-of-palm contained two isoenzymes which were separated by polyacrylamide gel electrophoresis. The enzyme was inhibited by metal ions and p-CMB. The p-CMB inhibition was reversed by cysteine. The shikimate dehydrogenase was competitively inhibited by protocatechuic acid (Ki 7.5 × 10?4M), and Km values of 0.021 mM and 0.011 mM for shikimic acid and NADP+, respectively, were obtained at pH 9.5 in Tris-HCl-glycine buffer. The molecular weight determination was performed on Sephadex G-100 and the MW was estimated to be 50,000 daltons. 相似文献
999.
Vasilenko O. A. Maier A. A. Chashchin V. A. Gulaeva E. N. Bus'ko V. I. 《Journal of Engineering Physics and Thermophysics》1985,49(3):1105-1108
A method of calculating the temperature resistance coefficient and its temperature dependence for resistive materials in the approximation of a matrix-statistical structure is outlined.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 3, pp. 477–481, September, 1985. 相似文献
1000.
E. WITTIG DE PENNA P. CARREñO X. URRUTIA L. LOPEZ D. BALLESTER 《Journal of food science》1987,52(5):1434-1435
Cookies enriched with 0, 5, 10, 15, 20, and 25% full-fat sweet lupine flour (FFSL) were evaluated by a sensory panel using the rank of preference and paired comparison tests. Cookies with 0, 5, and 10% FFSL were preferred while those containing 20 and 25% FFSL were rejected (p≤0.01). Studies conducted with school children showed similar acceptability for 0 and 10% FFSL-containing cookies which was different (p = 0.05) from those containing 20% FFSL. Fortification of the basic formula with 10% FFSL was recommended on the basis of acceptability. 相似文献