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The clpB gene in Acetobacter pasteurianus was cloned and characterized. Although the clpB gene was transcribed in response to a temperature shift and exposure to ethanol, the clpB disruption mutant was only affected by high temperature, suggesting that the ClpB protein is closely associated with heat resistance in A. pasteurianus.  相似文献   
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The development of nonchromium catalyst for fatty alcohol production   总被引:2,自引:0,他引:2  
Fatty alcohols are obtained by hydrogenation of fatty acid methyl esters derived from coconut oil and palm kernel oil. Cu−Cr has been widely used as a hydrogenation catalyst. We have developed a new environment-friendly catalyst that could substitute for the conventional Cu−Cr catalyst, preventing the release of toxic hexavalent Cr. Here we report the development of Cr-free, Cu−Fe−Al oxide catalyst. We found that iron has a strong promoting effect nearly equivalent to that of Cr and that the addition of Al significantly improved the reuse property (durability) through a study of trivalent metal addition to Cu. Powder X-ray diffraction analysis of the used catalyst revealed that the Al addition suppressed the transformation of the CuFe2O4 component (Cu−Fe spinel) to α-Fe. It was concluded that the stabilization of CuFe2O4 during reduction improved the catalyst durability. A plant-scale experiment confirmed that the Cu−Fe−Al oxide catalyst performs as well as the conventional Cu−Cr catalyst.  相似文献   
55.
We performed retrospective analysis of hepatic veno-occlusive disease (VOD) in 57 cases with leukemia after allogeneic bone marrow transplantation (BMT). Prostaglandin E1 (PGE1) was used to prevent VOD in 8 cases at a dose of 0.3 micrograms/kg/hr from day -8 to day 30. No VOD was noted in the PGE1 group, while the incidence of VOD was 8/49 (16.3%) in the non PGE1 group. In twelve patients with pretransplant liver dysfunction, VOD was noted in 0/3 in the PGE1 group and 4/9 (44.4%) in the non PGE1 group, respectively. However, prophylactic effects of PGE1 on VOD is not significant in this study, so further studies are needed to determine the efficacy of PGE1. One of 8 patients with PGE1 prophylaxis had edema and erythema on extremities, however, severe toxicity was not experienced.  相似文献   
56.
The RpoH in Acetobacter pasteurianus NBRC3283 was characterized. It was revealed that the rpoH controls the expression of groEL, dnaKJ, grpE, and clpB to different extents. In addition, the rpoH disruption mutant became apt to be affected by heat, ethanol, and acetic acid, indicating its importance in acetic acid fermentation.  相似文献   
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As part of our studies focused on the design of 1‐[((hetero)aryl‐ and piperidinylmethyl)amino]‐2‐phenyl‐3‐(1H‐1,2,4‐triazol‐1‐yl)propan‐2‐ols as antifungal agents, we report the development of new extended benzylamine derivatives substituted at the para position by sulfonamide or retrosulfonamide groups linked to alkyl or aryl chains. These molecules have broad‐spectrum antifungal activities not only against Candida spp., including fluconazole‐resistant strains, but also against a filamentous species (A. fumigatus). Concerning fluconazole resistance, selected compounds exhibit the capacity to overcome CDR and ERG11 gene upregulation and to maintain antifungal activity despite a recognized critical CYP51 substitution in C. albicans isolates. Synthesis, investigation of the mechanism of action by sterol analysis in a C. albicans strain, and structure–activity relationships (SARs) are reported.  相似文献   
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Abstract

The items to be considered prior to selection of dryers are explained, and a simple method for a rough estimation of dryer sizes was proposed based on data obtained from operating industrial dryers.

The equations of basic design for batch or continuous type dryers were derived. The heat was supplied to materials by convection and/or conduction. The equations were simplified to the case when the falling rate of drying is proportional to the moisture content of materials under the constant drying conditions. The heat transfer coefficient used in the equations can be determined based on the calculations or the data obtained from the experimental or industrial dryers. The equations are useful for estimating the scale-up effect of dryers.  相似文献   
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Free-space laser communication systems use optical-fiber-based technology such as optical amplifiers, receivers, and high-speed modulators. In these systems using single-mode fibers, the fiber coupling efficiency is one of the most significant issues to be solved. Optimum relationships between a focused optical beam and mode field size of the optical fiber in the presence of random angular jitter are discussed in relation to fiber-coupled optical systems. Maximum fiber coupling efficiency is analytically derived with the optimum Airy disk radius normalized by the mode field radius as a function of random angular jitter. The fade level of fiber-coupled signals at desired fade probability is investigated. It is shown that the average bit error ratio significantly degrades with the random angular jitter normalized by the mode field radius larger than about 0.3 when the Airy disk size is optimally selected.  相似文献   
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