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41.
Kanji Hirabayashi 《Journal of Electronic Testing》1995,6(3):331-332
Assuming that the distribution of path delays introduced by variations in the manufacturing process is exponential instead of gaussian, the interdependence problem between delay-optimization of synthesized networks and parametric yield has been revisited. The result confirms the claim of Williams, Underwood, and Mercer. The exponential distribution is the consequence of simultaneous occurrence of gate delay faults along the path. 相似文献
42.
This paper analyses the HIPERLAN channel access mechanism. Both a purely mathematical and a simulation model are built in order to evaluate the two successive phases of the contention scheme. Several optimisations, based on the choice of parametric values, are proposed, evaluated and compared. 相似文献
43.
44.
45.
Certain strains of lactic acid bacteria present in commercial cheese starters, characterized by faint transparent colonies on an agar plate containing 1 mg kg −1 crystal violet (CVT), were identified as Lactococcus lactis subsp. (ssp) lactis biovar diacetylactis. The effect of citrate on the growth of these strains (CVT strains) in the presence of glucose was studied, in comparison with L. lactis strains. Molar growth yield from glucose (YG, g dry weight/mole of glucose consumed) for CVT strains grown on glucose plus citrate was significantly higher than the control (i.e. without citrate), but not for other L. lactis strains tested. Enhanced YG was also observed at a pH-controlled experiment, indicating that enhanced YG did not result from a buffering effect of citrate. CVT strains, in contrast to other strains of the same species, were shown to obtain enough energy to enhance YG on glucose–citrate mixtures. 相似文献
46.
对酒鬼酒翻醅的生产工艺进行了研究,大曲与糖化料预先配合,加入适量活性干酵母的技术措施,大幅度地提高了酒鬼酒翻醅后出酒率。 相似文献
47.
L
A Metho J
R
N Taylor P
S Hammes P
G Randall 《Journal of the science of food and agriculture》1999,79(13):1823-1831
Grain protein content affects the flour yield and breadmaking characteristics of wheat (Triticum aestivum L). In this study, grain protein yield, grain protein content, flour yield and loaf volume were quantified for four wheat cultivars (Inia, Carina, Kariega and SST 86) grown under six different soil fertility regimes in a long-term fertilisation and irrigation experiment at the University of Pretoria. The experimental design was a randomised complete block replicated four times, with fertility as the main plots and cultivars as the subplot treatments. Grain protein yield, flour yield, loaf volume and mixograph dough peak mixing time varied among cultivars and soil fertility situations. Grain protein content differed among cultivars, but mixograph water absorption and dough characteristics did not differ. The highest grain protein yield was 873 kg ha−1 for Carina and the lowest 527 kg ha−1 for SST 86. Grain protein content averaged 131 g kg−1 for Carina and 122 g kg−1 for Kariega. Breadmaking performance showed that in a well-balanced soil fertility situation, Kariega produced 1025 cm3 of loaf volume while Inia averaged 950 cm3. Grain protein yield increased with increasing soil fertility, but grain protein content, flour yield, loaf volume, water absorption and mixograph peak mixing time varied with soil fertility. The interaction between cultivar and soil fertility was significant for grain protein yield, grain protein content, flour yield, loaf volume and water absorption but not dough peak mixing time. The results indicate cultivar differences in breadmaking quality characteristics and that soil fertility status affects grain protein yield, grain protein content, flour yield, loaf volume potential and water absorption but not mixograph peak mixing time and dough characteristics. © 1999 Society of Chemical Industry 相似文献
48.
Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily. 相似文献
49.
Chakrapani V. Varanasi Leon Chuck Lyle Brunke Jack Burke Andrew D. Chaney Paul N. Barnes 《Journal of Electronic Materials》2007,36(10):1265-1269
A simple testing method is used to compare the yield strengths (YS) of biaxially textured metallic substrates (Ni and its
alloys) presently under development for YBa2Cu3O7−x
coated conductors. This method is based on a retired ASTM D3379 tensile test standard method that was originally recommended
for single filament materials. Several common textured substrates, such as Ni, Ni-3at.%W, and Ni-5at.%W, procured from different
manufacturers, were tested using this method, and the data were compared with the values reported in the literature. A new
alloy substrate (constantan (Cu55-Ni44-Mn1wt.%)) that is biaxially textured in-house was also tested using this method, and
the YS data were compared with those of other substrates. For the substrates used in this study, the data obtained using this
method indicated that Ni substrates have YS of ∼52 MPa, Ni-3at.%W substrates have YS of ∼106 MPa, Ni-5at.%W substrates have
YS 163 MPa, and Cu55-Ni44-Mn1 wt.% substrates have YS of 74 MPa. 相似文献
50.