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991.
M. Djaeni P. Bartels J. Sanders G. van Straten A. J. B. van Boxtel 《Drying Technology》2007,25(6):1053-1067
This work discusses the potential of three multistage zeolite drying systems (counter-, co-, and cross-current) with a varying number of stages. The evaluation showed that for 2-4 stages with heat recovery the efficiency of the systems ranges between 80 and 90%. Additionally, by introducing a compressor, the latent heat in the exhaust air from the regenerator is recovered and used to heat the inlet air for an additional drying stage. As a result, for the counter-current drying system and compressor pressure 1.5-2 bar, a maximum energy efficiency of 120% is achieved, which results in halving the energy consumption compared to conventional drying systems. 相似文献
992.
993.
V. N. Kostyukov A. P. Naumenko V. A. Starikov A. A. Sinitsyn A. M. Volkov A. S. Rubanenko A. V. Rykin O. V. Kuznetsov 《Metallurgist》2007,51(11-12):596-604
Introduction of the BER? KOMPAKS® automated system at the Vyksa Metallurgical Plant to safely and efficiently manage the operation of the plant’s equipment has allowed the facility to begin operating that equipment based on real-time evaluations of its actual physical condition. Introduction of the new system has also allowed better coordination of repair-scheduling with ongoing production operations, significantly improved the reliability and readiness of the equipment for operation at 100% capacity, completely eliminated the human factor from the process of monitoring the condition of equipment, and made it possible to check the quality and timeliness of equipment maintenance and repair work so as to ensure safe, efficient operation of the entire production complex. 相似文献
994.
N. P. Matveiko P. G. Kramtsov G. E. Slepnev 《Journal of Engineering Physics and Thermophysics》1987,52(5):586-590
Electrodes with different composition were prepared by the method of pressing followed by sintering of the graphite and vanadium disilicide powders, and their electrochemical and corrosion properties in water solutions of electrolytes were studied.Translated from Inzhenerno-Fizicheskii Zhuraal, Vol. 52, No. 5, pp. 802–707, May, 1987. 相似文献
995.
S A Brantmeier M E Bellin S K Boehm S M Bushmeyer C L Kubajak M R Dentine R R Grummer R L Ax 《Journal of dairy science》1987,70(10):2138-2144
Concentrations of estradiol-17 beta in follicular fluid were correlated to follicular size, stage of estrous cycle, location of corpus luteum, and presence of large follicles. Paired ovaries were obtained from 481 nonpregnant cows at slaughter and follicles were classified as ipsilateral or contralateral to the corpus luteum. Follicular fluid estradiol-17 beta concentrations from 2494 small, 1485 medium, and 396 large follicles were quantified by radioimmunoassay. Stage of estrous cycle was estimated by visual examination of the corpus luteum. Follicles in stage 1 of the estrous cycle (d 1 to 4) had the highest estradiol-17 beta concentration and the smallest mean follicular diameter. Location of follicles relative to the corpus luteum had no influence on estradiol-17 beta concentrations. As follicular size increased, concentration of estradiol-17 beta also increased. The presence of a single large follicle did not affect the concentration of estradiol-17 beta in medium or small follicles. In contrast, if multiple large follicles occurred in the same cow, concentrations of estradiol-17 beta were significantly lower in medium but not small follicles. 相似文献
996.
S. A. Burns A. Locascio 《International journal for numerical methods in engineering》1991,31(7):1295-1318
A monomial-based method for solving systems of algebraic non-linear equations is presented. The method uses the arithmetic-geometric mean inequality to construct a system of monomial equations that approximates the system of non-linear equations. A change of variables transforms the monomial system into a system of linear equations, which is readily solved. Special properties of the monomial method are identified and their significance is discussed. Invariance properties of the monomial method produce a built-in, self-adjusting scaling of the variables and equilibration of the equations of the linear system. Other special properties can lead to useful bounds on, and invariances of, the conditioning of the linear system. An invariance to uniform scaling is responsible for extremely rapid convergence to the equation surfaces in the initial iterations. An invariance to multiplication of the algebraic equations by a certain class of functions leads to a useful insensitivity to form of the algebraic system. Insensitivity of the monomial method to solutions with negative components avoids meaningless solutiuons of the algebraic system that appear as undesirable by-products of the formulation. A practical engineering design problem is solved to demonstrate the special properties of the monomial method. 相似文献
997.
M. Saez N. Tauveron T. Chataing G. Geffraye L. Briottet N. Alborghetti 《Nuclear Engineering and Design》2006,236(5-6):574-2004
The direct coupling of a Gas Cooled Reactor (GCR) with a closed gas-turbine cycle leads to a specific dynamic plant behaviour. This behaviour is described and illustrated through computer analyses performed at CEA with the computer code CATHARE. This analysis requires a 1D code able to simulate the whole reactor, including the core, the vessel, the piping and the components (turbine, compressors, heat exchangers).This paper is devoted to deblading accidents. The problems and solutions encountered in various types of gas-turbines are presented: aero engines, steam turbines (EDF-Porcheville steam turbine accident feedback) and finally the feedback from previous High Temperature Gas Reactor experiments (EVO helium loop, HHT project and other HTR projects) are displayed. From this literature survey, some recommendations are drawn for a future High Temperature Reactor. It is shown that for safety reasons in case of deblading, a horizontal shaft aligned with the reactor vessel is recommended for the turbomachinery.This paper presents simulations of different scenarii performed with CATHARE code:
- (a) Turbine deblading with and without reactor trip. In these calculations, a pessimistic assumption has been made: all turbine blades break off.
- (b) Total flow blockage. The flow area is entirely blocked by the turbine blades.
- (c) Partial flow blockage. Previous conclusions consider the worst cases of deblading and total flow blockage. An intermediate case based on a partial deblading has also been performed.
998.
The blast furnace in the blast-furnace shop at the West Slovakian Metallurgical Combine is charged by means of a complex system
that usually includes the following: an ore yard with a hopper gantry; a system to collect, weigh, and transport the charge
materials to the top of the furnace; the charging apparatus of the furnace; a system that controls the charging operation.
The use of continuous-acting mechanisms facilitates charging of the ore-bearing materials in the charge while minimizing the
content of the −5-mm fraction of these components and the number of coke particles smaller than 25 mm. The productivity of
the furnace could be increased further, which would allow the addition of an efficient aspiration system and make it easier
to fully automate the furnace.
__________
Translated from Metallurg, No. 7, pp. 45–46, July, 2006. 相似文献
999.
Wastewater treatment technologies suitable for serving large populations are generally reliable and reasonably cost-effective, yet they are almost always financially inappropriate for small communities (< 2,000 p.e.). Comparative cost data suggests that waste stabilization ponds should be an attractive option for small communities, yet perceptions relating to land costs, climate and effluent quality have limited their application in the UK. This paper details typical UK land costs, climate and winter performance data for a pilot-scale waste stabilization pond with various upgrading technologies: system A, two tertiary maturation ponds in series; B, two tertiary maturation ponds in series followed by a reed bed channel; C, a control rock filter; D, an aerated rock filter; and E, a constructed wetland. System D was found to perform best, closely followed by system B. 相似文献
1000.
Aboubakar Sako Kenneth G. MacLeod Catherine M. O’Reilly 《Journal of Great Lakes research》2007,33(4):806-815
In this study, we measured growth trends in oxygen and carbon isotopic ratios in whole sagittal otoliths from three adult centropomid fish (Lates stappersii) from each of three sub-basins of Lake Tanganyika, East Africa. Sampling density was 20 to 50 samples per otolith. Both δ18O and δ13C values increase with age. The δ18O data suggest that otoliths were precipitated near the expected equilibrium with the ambient environment (ca. +3.5‰) and support a migration pattern from surface waters during larval stages to deeper waters (40 to 80 m) for mature fish. Relatively high δ18O values in the southern sub-basin are consistent with cooler temperatures in the region during seasonal upwelling. The δ13C increase from otolith core to edge is large (up to 4‰) and is interpreted as due to ontogenetic changes in diet and contributions from a decrease in the proportion of respired CO2 incorporated into otolith carbonate as metabolic rates of the fish dropped with maturity. The data seem to successfully reveal life strategy and migration patterns of L. stappersii, document regional differences in lake conditions, and provide a record of temperature within the water column during which the fish lived. Higher resolution studies and analyses of historical samples could be used to constrain modern and past growth patterns, and to reconstruct past temperature gradients and productivity patterns in the lake. 相似文献