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31.
A multiphase inactivation model of an advanced oxidation process that uses O3/UV was developed and successfully validated with pilot-scale experiments. Using the inactivation rate constants and dispersion number estimated from the pilot-scale experiments, the inactivation efficacy of O3/UV under full-scale conditions was predicted. Uncertainty analysis in quantitative microbial risk assessment was performed to examine the impact of the hydraulic conditions of the O3/UV contactor. It was demonstrated that the estimation of the dispersion number in the full-scale contactor is necessary to improve the accuracy of the risk estimates.  相似文献   
32.
The friction loss of gears and its quantitative estimation are important problems because of their relevance to energy conservation and load-carrying capacity. Recent research results do not provide satisfactory estimates of friction loss of spur gears. Therefore, the authors carried out experiments to study the influences of lubricating oil viscosity and additives, as well as base oil type and load and rotational speed on friction loss of spur gears. Base oil types used were paraffin mineral, poly-α-olefin, and polyglycol with several oil viscosities. An EP and a mild EP additive were studied in these oils. Finally, the temperature rise of teeth of gears as a function of friction power loss was investigated, and an empirical formula for calculating the temperature rise of the spur gear teeth was derived.  相似文献   
33.
The aim of this study was to determine the principal active molecules in the acid phosphatase (AcP) fraction of skim milk origin using immunostaining and AcP staining. The AcP fraction was separated from skim milk at 0.38 m NaCl using carboxymethyl cellulose chromatography at pH 5.2. The molecular mass of the active molecule in AcP fraction was estimated to be 80 kDa by immunostaining and AcP staining. The 80 kDa protein was analyzed by a protein sequencer, using the automated Edman degradation method; the first thirteen N-terminal amino acid sequence obtained were shown to be APRKNVRWXTIXQ. For that amino acid sequence, there was 84% (11/13 residues) homology with the amino acid sequence of bovine lactoferrin (LF). The AcP fraction and commercial LF showed a similar AcP activity profile, having an optimum pH of 4.5 and temperature of 60 °C. Thus, the AcP fraction from bovine skim milk was isolated and the principal active molecule present was tentatively identified as LF.  相似文献   
34.
The present study explains the application of a numerical simulation to investigate the thermal environment of a new riverside residential development in summer. The case study area consists of more than one hundred two-story detached houses built next to a river near Tokyo, Japan. According to the meteorological data, prevailing wind directions are at an angle to the northbound river flow affecting the microclimate of the study area in terms of surface temperature of land and buildings, air temperature and wind distribution at pedestrian height. These factors have been estimated using the stepwise CFD (computational fluid dynamics) simulation of radiation, conduction and convection. This method leads to an improvement of outdoor thermal environment by manipulating the site design and layout planning scenarios. The effect of river, permeable pavements and green space on thermal environment is examined by the site design options. Likewise, the impact of building arrangement is evaluated using alternative layout planning scenarios. In total, five scenarios have been simulated for the proposed sustainable development as explained in the paper. Above simulations provided an insight into the mitigation effects of each countermeasure. It is also shown that the management of inflow paths and the creation of wind paths for the interior of the site have the potentials to improve the outdoor thermal environment of riverside residential development.  相似文献   
35.
An analysis has been performed on the heat transfer with thermal radiation by flowing gaseous suspensions of solid and/or liquid fine particles in an inlet section of circular tube. The examination of the results on temperature profiles of both phases and heat transfer parameters illustrates that the multiphase medium is pertinent to heat transfer at high and extremely high temperatures because of the absorption behavior of the dispersed phase for thermal radiation and the results are summarized for wide ranges of parameters such as loading ratio, heat transfer characteristics between two phases, optical thickness of a duct, interaction parameter of conduction with radiation, etc. The interactions between the convection to fluid and the radiation are. thereafter, examined in some details.  相似文献   
36.
CO preferential oxidation on a novel Ru catalyst greatly improved in activity and selectivity over a wide temperature range by the pre-treatment of H2 reduction was characterized. The high performance was obtained by increasing the population of surface Ru(0) which improved O2 activation at low temperatures. Methanation of CO on the catalyst can also contribute to the final CO clean-up from ca. 100 to <1 ppm at low temperatures where the influence of CO2 methanation can be ignored.  相似文献   
37.
CT scans showing a hyperattenuating rim within the liver were retrospectively evaluated in 10 patients to clarify the character, aetiology and clinical significance. All patients had hepatic tumours (7 cavernous haemangiomas in 6 patients, 3 metastatic tumours and 1 hepatocellular carcinoma) as well as fatty infiltration of the liver. Typical features of the hyperattenuating rim on noncontrast CT of the liver included (1) attenuation similar to that of the spleen, (2) a circular or semicircular shape, (3) a width of a few millimeters, (4) peritumoral localization and (5) loss of visualization with contrast enhancement. No such rims were noted around hepatic tumours unassociated with fatty infiltration. Peritumoral sparing of fatty infiltration was inferred. A hyperattenuating rim on noncontrast liver CT, although rare, suggests the presence of a hepatic tumour in fatty liver.  相似文献   
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39.
A 75‐year‐old Japanese man presented with pruritic blisters and macules on his trunk and extremities. He had been on hemodialysis for 4 years because of chronic renal failure, and in recent months, a polymethylmethacrylate membrane had been used for dialysis. After a change in dialysis membrane to a cellulose triacetate membrane, pruritic tense blisters developed on the extremities in combination with marked blood eosinophilia. Physical examination showed erythematous macules and tense blisters on the trunk and extremities. A biopsy specimen of an erythematous macule showed subepidermal vesicles and eosinophils that attached to the dermal–epidermal junction. Serum level of eosinophilic cationic protein was elevated. From clinical, histological, and immunological findings, a diagnosis of bullous pemphigoid was made. New blisters continued to erupt during the period in which the patient used the cellulose triacetate membrane dialyzer, and even after the use of clobetasol propionate. It resolved only after the patient came back to the use of a synthetic membrane dialyzer. We discontinued the use of clobetasol propionate, and neither bullous eruptions nor blood eosinophilia recurred. These observations suggest that cellulose membrane may be involved in the development of bullous pemphigoid through activation of eosinophils in the blood and the skin lesion, as in the present case.  相似文献   
40.
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