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41.
1IntroductionHeattransferwithphasetransformationisamovingboundaryproblemoftenencounteredinthefieldsofmetalurgy,chemicalengine...  相似文献   
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Understanding changes in pathogen behavior(e.g.increased virulence,a shift in transmission channel) is critical for the public health management of emerging infectious diseases.Genome degradation via gene depletion or inactivation is recognized as a pathoadaptive feature of the pathogen evolving with the host.However,little is known about the exact role of genome degradation in affecting pathogenic behavior,and the underlying molecular detail has yet to be examined.Using large-scale global avian...  相似文献   
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Multiple morphological abnormalities of the sperm flagella(MMAF) are one of the major causes of male infertility and are characterized by multiple defects.In this study,we found that the coiled-coil domain-containing 189(Ccdc189) gene was predominantly expressed in mouse testes and that inactivation of the Ccdc189 gene caused male infertility.Histological studies revealed that most sperm from Ccdc189-deficient mice carried coiled,curved or short flagella,which are typical MMAF phenotypes.Immunoe...  相似文献   
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论21世纪高校图书馆模态   总被引:4,自引:0,他引:4  
本文以20世纪高校图书馆的运行模式和表现形态为基础,从高校图书馆的作用与地位、文献结构与文献权限、社会形象与馆员素质、读者结构与重组、服务方式与操作对象、规则协议与资源协作几个方面,对21世纪高校图书的模态进行了展望。  相似文献   
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Removal of cyclops in pre-oxidizing cooperation water treatment process   总被引:1,自引:0,他引:1  
Zooplankton cyclops propagates profusely in waterbody, cannot be effectively inactivated by conventional disinfec- tion process, and becomes a troublesome drinking water treatment problem. In this work, the qualitative and quantitative ex- perimental studies were carried out on inactivation of zooplankton cyclops using oxidants, such as chlorine (Cl2), chlorine dioxide (ClO2), ozone (O3), hydrogen peroxide (H2O2), ozone/hydrogen peroxide (O3/H2O2), chloramines (Cl2-NH3) and potassium permanganate (KMnO4). The influences of various factors include different oxidant dosages, organic substance contents and pH values. The results showed that currently available oxidants used all might inactivate cyclops in some extent. According to the experimental results, chlorine dioxide, ozone, ozone/hydrogen peroxide and chloramines can be selected as effective oxidants for inactivating cyclops because of their strong inactivation abilities. Then the synergic removal effects on cyclops with ozone, ozone/hydrogen peroxide pre-oxidation followed by conventional water treatment processes were investigated. The results showed that ozone and ozone/hydrogen peroxide pre-oxidation can inactivate cyclops effectively, which then can be removed thoroughly by conventional water treatment processes. Cyclops cannot appear in water after filtration with 1.65 mg/L of ozone and 6 mg/L of hydrogen peroxide, with the inactivation rate being 62% before conventional water treatment processes. Cyclops cannot appear in water after filtration with 1.8 mg/L of ozone, with the inactivation rate being 50% before conventional water treatment processes. For different oxidants, when removal rate was the best, the inactivation rate was not the same. These results may pro- vide reference and model for actual waterworks.  相似文献   
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In this study the MTP1 gene, encoding a type III integral transmembrane protein, was isolated from the rice blast fungus Magnaporthe oryzae. The Mtp1 protein is 520 amino acids long and is comparable to the Ytp1 protein of Saccharomyces cerevisiae with 46% sequence similarity. Prediction programs and MTP1-GFP (green fluorescent protein) fusion expression results indicate that Mtp1 is a protein located at several membranes in the cytoplasm. The functions of the MTP1 gene in the growth and development of the fungus were studied using an MTP1 gene knockout mutant. The MTP1 gene was primarily expressed at the hyphal and conidial stages and is necessary for conidiation and conidial germination, but is not required for pathogenicity. The Deltamtp1 mutant grew more efficiently than the wild type strain on non-fermentable carbon sources, implying that the MTP1 gene has a unique role in respiratory growth and carbon source use.  相似文献   
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We studied the decomposition of two haloacetic acids (HAAs), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), in water by single oxidants ozone (O3) and ultraviolet radiation (UV) and the advanced oxidation processes (AOPs) constituted by the combinations of O3/UV, H2O2/UV, O3/H2O2, and O3/H2O2/UV. The concentrations of HAAs were analyzed at specified time intervals to track their decomposition. Except for O3 and UV, the four combined oxidation processes remarkably enhance the decomposition of DCAA and TCAA owing to the generated very reactive hydroxyl radicals. The fastest decomposition process is O3/H2O2/UV, closely followed by O3/UV. DCAA is much easier to decompose than' TCAA. The kinetics of HAA decomposition by O3/UV can be described well by a pseudo first-order reaction model under a constant initial dissolved O3 concentration and fixed UV radiation. Humic acids and HCO3 in the reaction system both decrease the decomposition rate constants for DCAA and TCAA. The amount of H2O2 accumulates in the presence of humic acids in the O3/UV process.  相似文献   
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