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961.
Number of groups in neutron-constant libraries for calculating nuclear fields and neutron parameters
Translated from Atomnaya énergiya, Vol. 79, No. 1, pp. 76–78, July, 1995. 相似文献
962.
Health risks for the public due to electric power generation are examined. The risk include those already known to exist due to air pollution and nuclear radiation and the newer potential risks of electromagnetic fields at power frequencies. It is shown that members of populations at risk are capable of making valuations of the worth to them of reduction of such risks. In soliciting their responses, the people are given scientific information on the nature of the hazards involved and their chances of being affected. Thus, the process is one of informed consent, preferable to having the valuation judgment imposed technocratically. The process allows a cost benefit comparison without the moral dilemma of valuing human life and suffering.<> 相似文献
963.
Whey is an undurable product. treated very often as a waste which pollutes the natural environment. Whey which is a valuable source of protein, lactose, vitamins and mineral salts should be utilized completely. The present paper is a proposal of whey drying on porous carriers. It is proved experimentally that the proposed drying method guarantees good product quality. 相似文献
964.
The interaction between two molten-cast refractories o f grades KhATs-30 and Bakor-33 and glass-forming melts was studied experimentally. It was established that the diffusion reaction border at the site o f contact between the refractory and the liquid glass has a zonal structure that obeys the laws of diffusion metasomatism. Practical recommendations are presented.Translated from Steklo i Keramika, No. 8, pp. 9 – 13, August, 1996. 相似文献
965.
I. V. Stefanyuk E. L. Oleinikova L. G. Khodskii A. A. Sirotinskii E. K. Nazimova 《Glass and Ceramics》1993,50(3):112-116
Translated from Steklo i Keramica, No. 3, pp. 7–10, March, 1993. 相似文献
966.
967.
L. D. Monti P. E. Sandoli S. Costa V. C. Phan P. M. Piatti 《Journal of Automated Methods and Management in Chemistry》1993,15(5):177-181
Intermediate products of the metabolism of glucose, fat and amino-acid are important in the evaluation of such metabolic disorders as diabetes mellitus, liver disease and metabolic acidosis. In the present study, methods for the measurement of intermediate metabolites (lactate, pyruvate, alanine, β-hydroxybutyrate and glycerol) have been adapted to a fast centrifugal analyzer: the COBAS FARA. Correlation coeffcients rangedfrom 0.90 to 0.99, compared to established manual spectrophotometric methods. Within-run coeffcients of variation (CVs) ranged between 2.9 and 8.8% at low levels, between 1.5 and 5.7% at medium levels and between 1.2 and 5.6% at high levels. Between-run CVs were between 4.0 and 15.0% at low levels, between 1.7 and 7.0% at medium levels and between 1.3 and 2.7% at high levels. These fluorimetric assays for the determination of intermediate metabolites on COBAS FARA (Roche) have a good sensitivity and precision, are less costly than manual methods and can be used on a routine basis. 相似文献
968.
969.
The characteristics of SF6/He plasmas which are used to etch Si3N4 have been examined with experimental design and modeled empirically by response-surface methodology using a Lam Research Autoetch 480 single-wafer system. The effects of variations of process gas flow rate (20-380 sccm), reactor pressure (300-900 mtorr). RF power (50-450 W at 13.56 MHz), and interelectrode spacing (8-25 mm) on the etch rates of LPCVD (low-pressure chemical vapor deposition) Si3N4, thermal SiO2, and photoresist were examined at 22±2°C. Whereas the etch rate of photoresist increases with interelectrode spacing between 8 and 19 mm and then declines between 19 and 25 mm, the etch rate of Si3N 4 increases smoothly from 8 to 25 mm, while the etch rate of thermal SiO2 shows no dependence on spacing between 8 and 25 mm. The etch rates of all three films decrease with increasing reactor pressure. Contour plots of the response surfaces for etch rate and etch uniformity of Si3N4 as a function of spacing and flow rate at constant RF power (250 W) display complex behavior at fixed reactor pressures. A satisfactory balance of etch rate and etch uniformity for Si3N4 is predicted at low reactor pressure (~300 mtorr), large electrode spacing (12-25 mm), and moderate process gas flow rates (20-250 sccm) 相似文献
970.
S.B. Burson D. Bradley J. Brockmann E. Copus D. Powers G. Greene C. Alexander 《Nuclear Engineering and Design》1989,115(2-3)
The NRC's Research Program on Core-Debris/Cavity Interactions comprises two principal elements: (1) an analytical effort focused primarily on development of computer codes needed to predict the potential consequences of risk-significant severe-accident scenarios; and (2) an experimental component to provide insights into the relevant phenomenological processes and to develop the experimental data base necessary for validation of the codes. The analytical activities at Sandia National Laboratories (SNL) focus primarily on refinement and validation of the CORCON and VANESA codes. Two major experimental activities are also based at SNL: (1) the large-scale SURC tests address the thermal-hydraulic phenomena in the cavity as well as aerosol release associated with prototypical core-melt materials in various types of concrete crucibles, while (2) the WITCH and GHOST experiments are concerned with aerosol generation and radionuclide release phenomena. A program of small-scale special-effects tests at Brookhaven National Laboratory (BNL) is coupled to a concomitant model-development and code-validation activity. In addition, measurements are being made at Battelle Columbus Laboratory (BCL) to augment the thermochemical data base needed in the VANESA code to permit refined radiological source-term predictions. The current scope and status of this research is reviewed. 相似文献