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991.
原水浊度对水厂生产废水回用影响的研究 总被引:2,自引:0,他引:2
费霞丽 《哈尔滨商业大学学报(自然科学版)》2005,21(2):162-165
根据原水浊度的变化,从改善混凝条件优化净水工艺角度,对九龙江流域水厂生产废水的回用条件和作用规律进行了研究.结果表明,在一定的原水浊度条件下,生产废水回用的最佳含固率范围小于1%.当原水浊度小于60ntu时,最佳含固率随原水浊度的升高而升高,当原水浊度大于60ntu时.最佳含固率随浊度的升高而降低.研究还发现生产废水回用不会造成饮用水水质超标. 相似文献
992.
由于未来战争的残酷性、复杂性和作战负重量的增大,不仅对军人的身体素质(速度、力量、耐力、柔韧性、灵敏性等)提出了更高的标准,而且对军人的智能素质(心理素质)亦提出了更高的要求.要打赢未来高技术战争,不仅需要有强健的身体素质,还特别需要有良好的心理素质.从准确把握军事体能训练中心理训练的原则出发,并对其训练的内容和方法加以探讨,对于增强学员的心理素质,提高军事体能训练的质量以及适应未来作战心理潜能的需要,都有重要的指导意义. 相似文献
993.
Foracertainionosphericregion,duetomanyfactorsespeciallytheinvisiblesolarradiation,thechangelawofthetotalelectroncontent(TEC)isdifferentindaytimeandnighttime.ThecorrespondingmathematicalexpressionsofTECshouldalsobedifferent.Therefore,whenusingGPStomodelpreciseionosphericdelay,oneofthecriticalfactorsistoexactlydistinguishtheionosphericdaytimeandnighttimeandreasonablydescribetheTECchangecharacteristicsofthedifferentperiodsattheionosphericpiercepoint(IPP).Inthepast,inthefieldsofGPSresearcha… 相似文献
994.
M. Nishikimi T. Koshizaka K. Kondo T. Ozawa K. Yagi 《Cellular and molecular life sciences : CMLS》1989,45(2):126-129
A mutant strain of Wistar rats with L-gulono--lactone oxidase deficiency has recently been established. To investigate this deficiency by DNA and RNA blot hybridization analyses, a fragment of a previously cloned cDNA encoding rat L-gulono--lactone oxidase was used as a probe. When genomic DNA of the mutant rat was digested with several restriction enzymes, the probe hybridized to fragments of the same sizes as those produced from DNA of normal rats. Poly(A)+RNA from the liver of the mutant rat was found to contain an L-gulono--lactone oxidase-specific mRNA of a normal size at a comparable level to that of normal rats. An in vitro translation experiment revealed that the mRNA programmed the synthesis of an enzyme protein which had the same molecular weight as that of the translational product of the normal mRNA, although the amount synthesized was markedly reduced as compared with that synthesized with the normal mRNA. In accordance with this observation, a very low but definite degree of L-gulono--lactone oxidase activity was detected in the microsomes of the mutant rat by a newly developed, highly sensitive method.Acknowledgments. The authors thank Dr Susumu Makino, Shionogi Research Laboratories, Shionogi & Co., Ltd, Japan, for his kind donation of normal (ODS- +/+) and ODS (ODS-od/od) rats. This work was supported in part by Grant-in-Aid (59570103) for Scientific Research from the Ministry of Education, Science and Culture of Japan. 相似文献
995.
M. Revel 《Cellular and molecular life sciences : CMLS》1989,45(6):549-557
Summary IL-6/IFN-2 appears to be one of the important mediators of the response to viral and bacterial infections and to shock. The biological effects now associated with IL-6/IFN-2 include: stimulation of immunoglobulin secretion by mature B lymphocytes (BSF-2 activity), growth stimulation of plasmacytomas and hybridomas (HGF activity), activation of T cells, stimulation of hepatic acute phase protein synthesis (HSF activity), stimulation of hematopoiesis, cell differentiation (DIF activity), inhibition of tumor cell growth (AP activity) and other IFN-like effects. As a typical cytokine, IL-6/IFN-2 is secreted by many cell types and acts in various combinations with other interleukins and interferons. 相似文献
996.
Summary A -glucosidase (linamarase) was purified 52-fold with a recovery of 27% from the haemolymph of the larvae ofZygaena trifolii, ESPER, 1783 (Lepidoptera, Zygaenidae). The final enzyme preparation was found to be nearly homogeneous on both disc polyacrylamide gel electrophoresis and SDS-polyacrylamide gel electrophoresis. The molecular weight of the enzyme was determined to be about 130 kDa; it consisted of two subunits of about 66 kDa. The enzyme showed an optimum between pH 4.5 and 5 with linamarin and a broad optimum between pH 3.5 and 6.5 for p-nitrophenyl--D-glucoside; the temperature optimum was 40°C. The -glucosidase showed a high specificity for its endogenous substrates linamarin and lotaustralin. Among the other natural and artificial substrates tested, only prunasin and p-nitrophenyl--D-glucoside were hydrolyzed by the enzyme, whereas linustatin, salicin, cellobiose and trehalose were not. The enzyme is strongly inhibited by -glucosylpiperidine. 相似文献
997.
M. Oimomi F. Hata N. Igaki T. Nakamichi S. Baba H. Kato 《Cellular and molecular life sciences : CMLS》1989,45(5):463-466
Summary Alfa-ketoaldehyde dehydrogenase, which was extracted and purified from human livers, may act on carbonyl compounds, such as 3-deoxyglucosone, and be involved in the control of glycation (Maillard reaction) in the body. 相似文献
998.
Summary Several 4, 5-unsaturated adenine nucleosides were shown to have antiproliferative activity against L 1210 leukemia cells in vitro. The active nucleosides were cytotoxic to the L 1210 cells as demonstrated by Trypan Blue uptake. The cytotoxicity was not induced by alterations in the ribonucleoside and deoxyribonucleoside triphosphate levels of the L 1210 cells. 相似文献
999.
Differences in the tissue content of prothymosin during the early postnatal development of male and female rats are reported. Thymus and spleen have been found to contain significantly higher amounts of prothymosin in the newborn and prepubertal animals, as compared to adults, whereas liver has been found to contain low levels of prothymosin throughout development. These findings indicate a functional association of prothymosin with the proliferating lymphoid tissues of the young rat. 相似文献
1000.
J. C. Lacey Jr N. S. M. D. Wickramasinghe R. S. Sabatini 《Cellular and molecular life sciences : CMLS》1992,48(4):379-383
We have studied the chemistry of aminoacyl AMP to model reactions at the 3 terminus of aminoacyl tRNA for the purpose of understanding the origin of protein synthesis. The present studies relate to the D, L preference in the esterification of 5-AMP. All N-acetyl amino acids we studied showed faster reaction of the D-isomer, with a generally decreasing preference for D-isomer as the hydrophobicity of the amino acid decreased. The -branched amino acids, Ile and Val, showed an extreme preference for D-isomer. Ac-Leu, the -branched amino acid, showed a slightly low D/L ratio relative to its hydrophobicity. The molecular basis for these preferences for D-isomer is understandable in the light of our previous studies and seems to be due to preferential hydrophobic interaction of the D-isomer with ademine. The preference for hydrophobic D-amino acids can be decreased by addition of an organic solvent to the reaction medium. Conversely, peptidylation with Ac-PhePhe shows a preference for the LL isomer over the DD isomer. 相似文献