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81.
The effects of estrogen-induced hyperlipidemia on plasma lipid peroxidation, fatty acid composition and osmotic fragility of erythrocytes in chickens were studied. Young male chickens implanted with estrogen for three wk developed a marked hyperlipidemia. Plasma levels of triglyceride, cholesterol and phospholipid were elevated 68-, four- and 24-fold, respectively, over controls. There was also a two-fold increase in plasma lipid peroxidation measured by the thiobarbituric acid test. Vitamin E supplement (1,000 IU/kg diet) reduced the plasma lipid peroxidation to the control level, but had no effect on the plasma lipid content. Estrogen-induced hyperlipidemia resulted in changes in the fatty acid composition of membrane lipids of erythrocytes. The major changes were an increase in oleic acid from 10.0% to 14.2% and a decrease in linoleic acid from 31.3% to 26.0%. The erytrocytes with an altered membrane fatty acid composition were found to have an increased osmotic fragility. It was apparent that there was a direct correlation between the oleic acid content and the osmotic fragility of erythrocytes.  相似文献   
82.
A visualization study on the effect of forcing amplitude in tone-excited jet diffusion flames has been conducted. Visualization techniques are employed using optical schemes, which are a light scattering photography. Flame stability curve is attained according to Reynolds number and forcing amplitude at a fuel tube resonant frequency. Flame behavior is globally grouped into two from attached flame to blown-out flame according to forcing amplitude; one sticks the tradition flame behavior which has been observed in general jet diffusion flames and the other shows a variety of flame modes such as the flame of a feeble forcing amplitude where traditionally well-organized vortex motion evolves, a fat flame, an elongated flame, and an in-burning flame. Particular attention is focused on an elongation flame, which is associated with a turnabout phenomenon of vortex motion, and on a reversal of the direction of vortex roll-up. It is found that the flame length with forcing amplitude is the direct outcome of the evolution process of the formed inner flow structure. Especially the negative part of the acoustic cycle under the influence of a strong positive pressure gradient causes the shapes of the fuel stem and fuel branch part and even the direction of vortex roll-up to dramatically change.  相似文献   
83.
Hydrogen sulfide gas was removed in a 2-dimensional gas-lift reactor by the photosynthetic microorganismChlorobium thiosulfatophilum using light emitting diodes (LEDs) as a light source. LEDs saved light energy by 99% compared with the incandescent light source. The plate-type gas-lift reactor removed hydrogen sulfide five times better per unit mg of protein, and performed two times better in the maximum performance per unit luminous flux, compared with cylindrical fermentors.  相似文献   
84.
通过构造砂页岩互层结构,并根据渗透率对砂岩层岩性进行分类,建立了多岩相非均质模型,利用多组分多相流数值模拟软件TOUGH2/ECO2N探究二氧化碳注入深部互层咸水层后的分布特征,结果显示二氧化碳聚集在低渗透性的页岩层底部,呈分层结构,砂岩层中优先在渗透率较高的岩相中运移并呈分散分布;超临界二氧化碳不断溶于地层水,含饱和二氧化碳的咸水密度增加并缓慢下沉,无明显分层现象。  相似文献   
85.
The aim of this paper is to study the electrochemical behavior of Si-C material synthesized by heating a mixture of silicon and polyvinylidene fluoride (PVDF) in the ratios of 5, 20, and 50 wt%. The particle size of the synthesized material was found to be increased with increase in the PVDF ratio. The coexistence of silicon with carbon was confirmed from the XRD analysis. A field emission scanning electron microscope (FESEM) study performed with the material proved the improvement in coating efficiency with increase in the PVDF ratio. Coin cells of the type 2025 were made by using the synthesized material, and the electrochemical properties were studied. An electrode was prepared by using the developed Si-C material. Si-C|Li cells were made with this electrode. A charge|discharge test was performed for 20 cycles at 0.1 C hour rate. Initial charge and discharge capacities of Si-C material derived from 20 wt% of PVDF was found to be 1,830 and 526 mAh|g, respectively. Initial charge/discharge characteristics of the electrode were analyzed. The level of reversible specific capacity was about 216mAh/g at Si-C material derived from 20 wt% of PVDF, initial intercalation efficiency (IIE), intercalation efficiency at initial charge/discharge, was 68%. Surface irreversible specific capacity was 31 mAh/g, and average specific resistance was 2.6 ohm * g.  相似文献   
86.
To design a supercritical fluid extraction process for the separation of bioactive substances from natural products, a quantitative knowledge of phase equilibria between target biosolutes and solvent is necessary. How-ever, mostly no such information is available in literature to date. Thus in the present study, illustratively the solubility of bioactive coumarin and its various derivatives (i.e., hydroxy-, methyl-, and methoxy-derivatives) in supercritical CO2 were measured at 308.15–328.15 K and 10–30 MPa. Also, the pure physical properties such as normal boiling point, critical constants, acentric factor, molar volume and standard vapor pressure for coumarin and its derivatives were estimated. By these estimated information, the measured solubilities were quantitatively correlated by an approximate lattice equation of state proposed recently by the present authors.  相似文献   
87.
To provide context-based personalized services utilizing smart appliances in a smart home environment, we propose a framework for PersonAlized Service disCovery Using FuZZY-based CBR and Context Ontology (PASCUZZY). Basically, the PASCUZZY framework is implemented on case-based context ontology. To generate and manage the case instances on the case-based context ontology, we adopt the fuzzy set theory to transpose numerical-type context data sensed from the surrounding environment. The context is transposed to linguistic-type context instances on the context ontology. In addition, to formalize and manage the context and services as multi-attributed data, the context ontology was developed reflecting the structure of cases borrowed from case-based reasoning. Furthermore, we propose adaptation methods to adjust the generic fuzzy membership functions depending on the inhabitants’ context. It is performed by modifying the values of the membership number and/or modifying the numbers of the linguistic terms that are based on the inhabitants’ context to affect the membership numbers. The adapted membership functions return the personalized degree of memberships depending on the specialized context of a specific fuzzy variable. Inevitably, the number of cases on the case-based context ontology will be increased from time to time. We apply Ward’s method not only to reduce the search effort via a hierarchical clustering on the case-based context ontology but also to find the most similar service as a solution to the new context. To verify the superiority of the PASCUZZY framework, we perform two kinds of evaluations. First, we evaluate the effectiveness of the adaptation of the fuzzy membership functions. Second, we verify the effectiveness of the application of a clustering method to the case instances of the case-based context ontology to identify the most similar service. Results of the experiment verified the effectiveness and superiority of the PASCUZZY framework.  相似文献   
88.
Binary blends of ethylene vinyl alcohol copolymers, containing 62 (EVOH-62) and 71 (EVOH-71) mole percent vinyl alcohols, with nylons (nylon-6, nylon-6/12, and nylon-12) have been prepared from melt mixing in a twin screw compounding machine. Morphological, thermal, rheological, and mechanical properties were determined. EVOH-62/nylon-6 and EVOH-71/nylon-6 blends showed homogeneous phase morphologies in the nylon-6-rich region, and fine phase separations (c.a. 2 × 10?7 m) in the EVOH-rich region. Melting point depression, positive deviations in viscosity and flexural modulus, and negative deviation in impact strength from the simple additive rule were generally observed. And the results were possibly interpreted in terms of compatibility and increased nylon/EVOH interactions over the nylon/nylon interactions. On the contrary, clean phase separations in large domains were observed from EVOH-71/nylon-6/12 and EVOH-71 /nylon-12 blends. Fibrillation was also obtained from EVOH rich blends. Probably due to the incompatible nature of these blends, yield at low rate of shear and a mechanical property drop were also observed.  相似文献   
89.
Specimens of two engineerig plastics i.e., poly(ether imide), PEI, and poly(2,6-dimethyl- 1,4-phenylene ether), PPE, were injection molded employing a 40t Van Dorn injection molding machine and industrial practices. The mold and melt temperatures and the injection speed were varied in a limited range which furnished acceptable samples. The density, birefringence, residual stress distributions, flexure and tensile properties, and crack development of the injection molded specimens were studied. Vacuum compression molded samples were also prepared to investigate the role played by the cooling rate in shaping microstructural distributions. The results revealed significant differences in the development of microstructure of the molded specimens of the two resins, which was related to rheology and molding conditions on one hand and to development of cracks and ultimate properties on the other hand.  相似文献   
90.
This paper proposes a method of exploring the local shape of an unknown object using the force and torque information obtained from active touch. In the first, we present a method to estimate an unknown curvature, using rolling and sliding motion with a force/torque sensor attached to the fingertip of the hand. Then, the normal curvature equation from 2D curvatures is obtained. Finally we present a reconstruction algorithm of local geometry by using a normal curvature equation, which is composed of principal curvatures and principal directions. The method is tested by using a hand-arm system consisting of an industrial robot arm and an anthropomorphic robot hand with 6-axis force/torque sensor. The feasibility of the proposed method is experimentally validated for objects with simple geometries such as cylinder, spheres etc.  相似文献   
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