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71.
本文报导了通过爆发性膨胀增加猪毛溶解度的方法,从而使得保毛脱毛法所回收的猪毛能够得到更有效的利用。 相似文献
72.
The square of the ratio of the abraded bending strength, d, to the unabraded bending strength, , is proposed as a measure of the resistance to crack propagation in ceramic materials. Data for various porcelains, glass-ceramics, and glasses showed that d is essentially constant and that (d/)2 decreased rapidly with increase of the unabraded strength. 相似文献
73.
The effects of dietary soybean protein on lipogenic enzyme gene expression in livers of genetically fatty rats (Wistar fatty) have been investigated. When Wistar fatty rats and their lean littermates (7-8-wk old) were fed a casein or soybean protein isolate diet containing hydrogenated fat (4% hydrogenated fat plus 1% corn oil) or corn oil (5%) for 3 wk, the hepatic messenger RNA concentrations and activities of lipogenic enzymes were significantly lower in rats fed soybean protein than in those fed casein, regardless of genotype or dietary fat. The conversion rates of thyroxine to triiodothyronine by liver microsomes and plasma triiodothyronine concentrations were lower in the fatty rats than in the lean rats and were significantly greater in rats fed soybean protein than in those fed casein. Conversely, plasma and liver triacylglycerol concentrations were lower in soybean protein-fed fatty and lean rats than in those fed casein. The body weight was less in the fatty rats fed soybean protein than in those fed casein after 3 wk of feeding. Moreover, dietary polyunsaturated fatty acids suppressed lipogenic enzyme gene expression in the lean rats but did not in the fatty rats. Dietary soybean protein appeared to be useful for the reduction of obesity. 相似文献
74.
A two-stage evolutionary method is developed to synthesize an optimal energy integrated distillation separation process: the search of the separation sequence, and the introduction of energy integration to the given separation sequence. For the former an evolutionary procedure first generating initial separation sequences and then evolving them is developed. For the latter an evolutionary procedure, first indicating the direction of the evolution by the thermodynamic analysis and then estimating it based on the objective function, is developed. An example problem of a five-component separation demonstrates the effectiveness of this proposed method. 相似文献
75.
We carried out the high temperature operating life test (HTOT) of CMOS ICs which include n-channel ROMs which were contaminated deliberately by leaving naked for a long time in the room ambient before moulding and got the bimodal failure distributions consisting of m = 0.3–0.5 and m = 2.6–3.3 parts in the Weibull chart.At the same time, the activation energy of 1.14 eV was obtained for m = 2.6–3.3 parts. In order to make clear the failure mechanism of the latter part, we made the test devices for detecting channel leakage current (abbrev. TEG) and checked the shift of leakage current and life acceleration due to temperature in HTOT. Then we found that leakage currents of TEGs have an incubation time, their activation energy was nearly equal to that of the CMOS ICs above and m = 2.6–3.3 for CMOS ICs were reasonably explained due to the gradient α of the logarithm of the median leakage current to that of time.Also we got a 40 times longer life for the same CMOS ICs coated with Si3N4 film instead of SiO2. And finally, from these data, we could verify the cause of failure in CMOS ICs. 相似文献
76.
Hosomi N Kawamura-Konishi Y Kawano R Fujii I Suzuki H 《Journal of Bioscience and Bioengineering》2005,99(3):222-229
Monoclonal antibody 2D7 generated against a transition-state analog N-methyl mesoporphyrin catalyzes a reaction for insertion of a cupric ion into mesoporphyrin. To investigate amino acid residues responsible for the catalytic activity, site-directed mutagenesis of the amino acid residues in the third complementarity determining region of the heavy chain (CDRH3) was performed on the antigen-binding fragment (Fab) of the antibody. Recombinant Fab mutants, in which Arg95 is replaced with Ala (R95A), Asp96 with Asn (D96N) and Met97 with Gly (M97G), were examined in terms of the catalytic efficiency of the reaction (k/K(S)) and the dissociation constant for N-methyl mesoporphyrin binding (K(d)) and these values were compared with those of the wild type. The k/K(S) values of the R95A and D96N mutants were 0.96% and 1.0% of that of the wild type, respectively, whereas the M97G mutant had no detectable catalytic activity. The K(d) values of the R95A and D96N mutants were 165 and 69 times that of the wild type, respectively, while that of the M97G mutant was similar to that of the wild type. The relationship between the k/K(S) and 1/K(d) values in the wild type and the R95A and D96N mutants suggests that Arg95 and Asp96 are responsible for stabilizing the transition-state in the catalytic reaction. The results of the M97G mutant allow us to propose that Met97 plays an important role in the catalytic activity probably due to a subtle and specific conformation of the antibody. 相似文献
77.
Yamanaka N Aoyama T Ikeda N Higashihara M Kamata K 《Hemodialysis international. International Symposium on Home Hemodialysis》2005,9(3):303-308
Entropy (ENT) is a newly developed measure of the complexity of heart rate variability (HRV). The aim of this study was to characterize the complexity of HRV in patients with end-stage renal disease (ESRD) and to find a possible clinical utility. Healthy subjects and patients with ESRD undergoing hemodialysis (HD) were recruited. The HD population consisted of patients with and without diabetes mellitus (DM). An electrocardiogram was recorded before HD, and blood pressure was measured during HD. The coefficients of variation of R-R intervals, high- and low-frequency components, and ratio of the low- to high-frequency components were measured as variables of HRV. The ENT was used to describe the complexity of HRV. Forty-six healthy subjects and 27 HD patients participated in this study. The ENT negatively correlated with the duration of DM (p = 0.001), systolic blood pressure (p = 0.003), and mean blood pressure (p = 0.004) before a HD session. ENT in HD patients was lower than that in healthy subjects (p < 0.01). ENT in HD patients with DM was lower than that in HD patients without DM (p < 0.01). The change in systolic blood pressure (DeltaSBP) during a HD session showed high correlations to ENT and ultrafiltration rate (UFR) of the dialyzer. The following equation was obtained: DeltaSBP = 2.25 x ENT - 2.28 x UFR - 21.27 (R2 = 0.805; p < 0.0001). ENT decreased with uremic and diabetic status. ENT also represents a possible prediction of hypotension during a HD session. 相似文献
78.
79.
Yasuhiro Kobayashi Masaaki Ohkita Michio Inoue 《Mathematics and computers in simulation》1978,20(4):285-290
In the previous papers [1][3], fractional powers were used to approximate elementary functions and their usefulness was proved with experimental results. In the present paper, some further investigations are reported. That is, elliptic integrals in Legendre's canonical form and Bessel functions are approximated by fractional powers. As the fractional power approximation, is discussed. When all coefficients c0, c1, c2, p are properly assigned, the accuracy of this approximation becomes comparable to that of the Chebyshev approximation using polynomials up to the third degree. 相似文献
f(x) c0 + c1x + c2xp
80.