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991.
Gorokhov V. P. Kolachev B. A. Parfenova O. A. Novikova M. B. 《Metal Science and Heat Treatment》2003,45(3-4):140-144
Boron segregation on the boundaries and in near-boundary volumes of alloy ÉI698-VD bearing up to 0.005% B and 0.01% B is investigated. The structure of fracture surfaces of impact specimens and the nature and distribution of boron carbides and borides on conventional and wide grain boundaries are described. Statistical analysis of controllable properties of production forgings with boron content in the supplied bars varying from at most 0.005% to at most 0.008% is performed. 相似文献
992.
Reconfigurable arrays by phase-only control 总被引:3,自引:0,他引:3
Bucci O.M. Mazzarella G. Panariello G. 《Antennas and Propagation, IEEE Transactions on》1991,39(7):919-925
Due to space or cost reasons, a single array antenna can be required to radiate more than one pattern, each pattern being selected by an electronic control, in which only the phase can be modified. A synthesis method for such a problem that is able to determine both the common amplitude and the various phases in an integrated way is presented. Moreover, the approach is flexible enough to take into account additional constraints and allows an efficient implementation. Some test cases showing the effectiveness of the method are presented 相似文献
993.
Factors influencing vitamin C stability in powder mixtures for beverages were studied and the main ways of its decomposition in products preserved in glass containers or paper packages covered with polymeric film were established. The phenomenon of vitamin C self-stabilization has been observed. 相似文献
994.
P. G. Bannov G. E. Shumilova N. A. Voronina O. V. Yurkina T. F. Alekseenko 《Chemistry and Technology of Fuels and Oils》1992,28(3):178-179
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 3, pp. 34–35, March, 1992. 相似文献
995.
Fluidized bed catalytic cracking of vacuum gas oil fractions in the presence of extract from phenol purification of heavy lubricating oil fraction as an aromatic addition was investigated. Results show that, at the optimum concentration of the addition, coke formation on the catalyst decreases by 50 to 70% while the content of olefinic hydrocarbons in gasoline decreases, with a corresponding increase in the content of paraffin/naphthene hydrocarbons. The yield of gasoline increases, while its octane number increases by about two units. 相似文献
996.
In reliability evaluation that uses minimal cut-set theory, the deduction of minimal cut-set orders is crucial and depends on all the identified minimal paths associated with the load point whose reliability indices are desired. An input-reduction programming technique that automates this deduction is presented. The technique can be applied to a network of any configuration and finds its greatest application in complex networks with multiple inputs. The power-system structure in the form of power-arms (termination busbars, branch and protective device) is the only initial input data needed. The results obtained, in terms of minimal paths and minimal cut-set orders for all the load points, using the program on a sample power system compare well with the existing results. The program is compact, modular, and easy to use and can be applied to any complex system to generate minimal cut-sets of the desired orders 相似文献
997.
The bias and angle dependences of the alpha-particle-induced charge collected by GaAs p-n junction diodes are investigated. These diodes, in which the n-layer overlays the p-layer, are fabricated in a semi-insulating GaAs substrate by Si and Mg ion implantation. 241 Am placed in a vacuum is used as an alpha-particle source with an initial energy of 4.03 MeV and a fluence of 5.4×10-5/s/μm2. The results show that the collected charge is nearly independent of the applied bias. This bias independence may be further evidence that the charge funneling process is not important in semi-insulating GaAs. A model not incorporating funneling can explain the measured angular dependence. Based on this model, the design principle for the buried p-layer structure is discussed 相似文献
998.
Lithium chloride yielded better extraction of fish muscle protein than sodium or potassium chloride under most conditions. In addition, constancy of extracted protein was better with lithium compared to potassium or sodium chlorides with respect to blending time, salt concentration, pH, temperature and foaming. With stored red hake muscle, LiCl was superior to NaCl with better extractability of protein and more linear reduction of extractability with storage time. Evidence indicated the superior performance of lithium compared to sodium was due to stabilization by lithium chloride of fish proteins towards denaturation. 相似文献
999.
L.M. MARERO E.M. PAYUMO A.R. AGUINALDO S. HOMMA O. IGARASHI 《Journal of food science》1991,56(1):270-271
Four weaning food formulations prepared from 70% 72-hr germinated rice/corn and 30% 48-hr germinated mungbean/cowpea were studied for tocopherol constituents and compared to ungerminated controls. γ-TocopheroIs were the major constituents of the mungbean-supplemented samples. The cowpea-supplemented foods contained a predominance of δ-tocopherols followed closely by γ-tocopherols, α-Tocopherols were comparatively higher in corn- than in rice-formulations. Tocopherols in the weaning foods decreased due to germination especially the γ-tocopherols of germinated corn-mungbean. 相似文献
1000.
Yu. M. Mosin I. A. Zakharov E. O. Lavrova M. A. Voinova 《Refractories and Industrial Ceramics》1992,33(1-2):38-43
Conclusions It is shown that in technically suitable conditions for shaping blanks by centrifugal casting, the deposition of the particles occurs with a streamline schedule, and the coarse fractions are deposited during acceleration of the rotation of the mold. The main factor influencing the density of the finely dispersed blanks is the duration of rotation, and for systems containing coarse filler, centrifugal acceleration. Regulating the dimensions (wall thickness) of the blank is possible by altering the concentration of solid phase in the slip and the degree of filling of the mold with it.Translated from Ogneupory, No. 1, pp. 22–24, January, 1992. 相似文献