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1.
Adsorption isotherms of pigments from alkali-refined oils (rapeseed, soybean, wheatgerm, safflower, corn, cottonseed and sunflower) were measured to investigate the applicability of the Langmuir and Freundlich equations and to elucidate the adsorption characteristics of pigments on sepiolites and standard activated clay. The Freundlich equation was more applicable to the experimental adsorption isotherms. The equilibrium amount adsorbed, acidity, pore size distribution and inflection of the Freundlich isotherms could be explained by assuming that pigments were adsorbed on the stronger acid sites in smaller pores at low concentration, and then in the larger ones when the concentration increased. The amount adsorbed increased with a rise in adsorption temperatures from 70 to 110°C, and the heat of adsorption was below 10 kcal/mol. The results indicate that pigments were physically adsorbed on the acid sites activated at higher adsorption temperatures.  相似文献   
2.
Effects of filtration bleaching on peroxide value (PV), thiobarbituric acid value (TAV) and carbonyl value (CV) of autoxidized soybean oil were investigated by using twenty-three kinds of activated carbon in order to improve oil quality. From the decreases in PV, TAV and CV and from the physical and chemical properties of activated carbons, it was suggested that hydroperoxides, aldehydes and ketones were adsorbed on the acid sites distributed over the surface or within the pores of the activated carbons while the autoxidized soybean oil flowed through the packed column. The residual tocopherols in autoxidized soybean oil and treated soybean oil were determined during storage. The decrease in oxidative stability of treated soybean oil seemed to be caused by elimination ofα-,β-andγ-tocopherols.δ-Tocopherol was chemically more stable thanα-,β- andγ-tocopherols in autoxidized soybean oil.  相似文献   
3.
CD147, a transmembrane glycoprotein that belongs to the immunoglobulin superfamily, and cyclophilin A (CypA), one of the binding partners of CD147, are overexpressed in tumor cells and associated with the progression of several malignancies, including both solid and hematological malignancies. However, CD147 and CypA involvement in cutaneous T-cell lymphoma (CTCL) has not been reported. In this study, we examined CD147 and CypA expression and function using clinical samples of mycosis fungoides (MF) and Sézary syndrome (SS) and CTCL cell lines. CD147 and CypA were overexpressed by tumor cells of MF/SS, and CypA was also expressed by epidermal keratinocytes in MF/SS lesional skin. Serum CypA levels were increased and correlated with disease severity markers in MF/SS patients. Anti-CD147 antibody and/or anti-CypA antibody suppressed the proliferation of CTCL cell lines, both in vitro and in vivo, via downregulation of phosphorylated extracellular-regulated kinase 1/2 and Akt. These results suggest that CD147-CypA interactions can contribute to the proliferation of MF/SS tumor cells in both a autocrine and paracrine manner, and that the disruption of CD147-CypA interactions could be a new therapeutic strategy for the treatment of MF/SS.  相似文献   
4.
Recently environmental control is regarded as important for good human health conditions, and toxic substances, including carcinogens and endocrine disruptors should be eliminated from our living environment. Hence easy quantitative methods are expected for a high level of environmental control. Our previous paper describes an easy quantitative analysis of nitrosamines (NAs) by capillary electrophoresis with an untreated fused silica capillary installed in an ordinary apparatus. In this paper, utilizing a novel type capillary column having sulfonated inner wall was investigated for improvements of separation performance and reproducibility. A sulfonated capillary causes fast and stabile electroosmotic flow because its inner wall is strongly negative charged. On a performance comparison of a sulfonated capillary with an untreated fused silica, analysis time reduction of c.a. forty percent was achieved, and relative standard deviations of migration times and peak responses were less than one third. In addition sample concentrations giving detection and quantitation limits were also reduced to a half.  相似文献   
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6.
Improving machined surface integrity is important for precision machining. The aim of this work is to develop a cutting tool, which enables to generate a localized compressive hydrostatic stress field in the vicinity of cutting point to suppress unnecessary plastic flow and to improve the surface integrity of workpiece. In this paper, as the first step a simple cutting tool attached with a laminar jig equipped with a small rectangular hole for cutting chip elimination was proposed, and a molecular dynamics simulation of nano-cutting of monocrystalline aluminum was performed in order to verify and reveal the effectiveness and issues, respectively, of proposed method for improving machined surface integrity. The obtained simulation results were also compared to those using a normal cutting tool in order to clarify the cutting mechanism. As a result, it was clarified that a high compressive hydrostatic stress field was successfully introduced in the vicinity of cutting point. Consequently, the burr formation and elimination of cutting chip were remarkably suppressed and smoothened, respectively by using proposed cutting tool.  相似文献   
7.
Liquid metal coolants have a significant role in the design of advanced fusion reactors. There is a need for an investigation of the thermal behavior of the liquid metal in working reactor environment, such as when fluid flow at low Prandtl number (Pr) with a buoyancy effect, is subjected to a magnetic field. In the present study, a direct numerical simulation (DNS) for a low Pr number fluid flow resulting in turbulent heat transfer with buoyancy effect under a magnetic field has been carried out between two vertical plates kept at different temperatures. In this simulation, the values of the Hartmann number (Ha) were 0 and 6, Pr number was 0.06 and Grashof numbers were 6.4 × 105, 9.6 × 105, and 1.6 × 106. The turbulent quantities of the parameters such as the mean temperature, turbulent heat flux, and temperature variance were obtained by direct numerical simulation (DNS). The Reynolds number (Re) for channel flow based on friction velocity averaged by both walls, viscosity, and channel half-width was set to be constant as Reτ* = 150. A uniform magnetic field was applied in a direction perpendicular to the walls of the channel. The profiles of mean velocity and velocity fluctuations became asymmetric, and the tendency was enhanced with the increasing buoyancy effect. However, by the application of a magnetic field the tendency decreased. In other words, thermal transport between the walls became weak due to the magnetic effect.  相似文献   
8.
Chronic fatigue syndrome (CFS) is often preceded by a viral illness and has recurrent "flu-like" symptoms. We compared demographic, clinical, and laboratory features (markers of inflammation and viral infection) among 717 patients with chronic fatigue (CF) with and without a self-reported postinfectious onset to identify associated clinical and biologic findings and to examine the subset of patients with CFS. Only subjective fever, chills, sore throat, lymphadenopathy, poorer functional status, and attribution of illness to a physical condition were significantly associated with a postinfectious onset. The features of patients with CFS were virtually identical to those of the broader category of patients with CF. We conclude that a postinfectious onset was not associated with a pattern of abnormalities across multiple psychosocial and biologic parameters.  相似文献   
9.
The adsorption isotherms of β-carotene on attapulgite and sepiolite were measured in the presence of 1,3-diglyceride in n-hexane to elucidate the relative inhibitory power of the diglycerides, hydroxyl group, carbon number, and double bond for adsorption bleaching. The adsorption mode of β-carotene was the Langmuir type. The inhibition of β-carotene adsorption may be caused by the polarity of diglycerides and the formation of diglyceride micelles. The relative inhibitory power of 1,3-diolein, 1,3-distearin, and 1,3-dipalmitin toward β-carotene adsorption was 1.49, 1.40, and 0.99, respectively. Therefore, the relative inhibitory power due to the hydroxyl group and increase in the carbon atom of the fatty acid in glyceride was 0.41–0.49.  相似文献   
10.
BACKGROUND: Global and regional changes in cerebral energy utilization are reported to characterize late life depression. METHODS: Twenty seven subjects with late life depression (9 prior to starting medication, 18 after starting) and 27 matched controls were evaluated with cordance, a quantitative EEG measure that reflects cerebral energy utilization. RESULTS: Global and focal (anterior and centrotemporal) differences were present in theta-band cordance between unmedicated depressed and control subjects. Depressed subjects receiving treatment had cordance patterns similar to controls. CONCLUSIONS: The presence of both diffuse and focal disturbances in energy utilization prior to initiating treatment indicates that cordance detects altered cerebral physiology in depressed patients, and that this measure may also be sensitive to treatment interventions.  相似文献   
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