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Langmuir-Blodgett films have been prepared from copper tetra-4-t-butylphthalocyanine. A voltage dependence of capacitance can be attributed to the presence of a Schottky depletion layer. The barrier potential was determined as l·4eV, and the carrier concentration about 1024m?3  相似文献   
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Etiology of corneal striae accompanying hydrogel lens wear   总被引:3,自引:0,他引:3  
Vertical striae in the posterior cornea were produced experimentally in ten human subjects by depriving the anterior corneal surface of its normal oxygen supply and inducing corneal edema. These striae were similar in appearance and time of occurrence to those observed in gel lens wearers. Three subjects also wore gel lenses and developed vertical striae while wearing their lenses. These striae were eliminated by increasing the oxygen concentration at the anterior lens surface. The data confirm many clinical observations which have suggested that verical striae are caused by corneal edema accompanying gel lens wear.  相似文献   
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A new method for the determination of azinphos ethyl (O,O-diethyl-S-(4-oxo-1,2,3-benzotriazin-3(4H)-ylmethyl) phosphorodithioate) in human plasma and in mouse plasma, tissue, and fat has been developed. The method is based on extraction with benzene or hexane and cleanup of fat and tissue samples by a minicolumn containing Florisil and sodium sulfate. Azinphos ethyl is eluted from the column with 10% acetonitrile in benzene and is concentrated to an appropriate volume for gas-liquid chromatographic analysis, using a 63Ni electron capture detector and a glass column containing 3% OV-1 on Gas-Chrom Q. The method is sensitive to 0.005 ppm in human plasma, 0.01 ppm in mouse plasma, 0.08 ppm in mouse liver, 0.05 ppm in mouse brain, and 0.10 ppm in mouse fat. The limit of detection is 2 pg; mean recoveries ranged from 96 to 98%.  相似文献   
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In this review of 7,464 consecutive infants born at North Carolina Memorial Hospital, hemolytic disease from ABO incompatibility was found to be two to three times as common in black infants as in white infants. The statistical significance of the difference remained high as more restrictive criteria for ABO hemolytic disease were applied. ABO disease, serious enough to cause an indirect serum bilirubin of 15 mg/100ml or higher, had an incidence in black newborns as great as the incidence of Rh hemolytic disease in whites. In contrast, the general prevalence and severity of hyperbilirubinemia was not found to be higher in black newborns than in white infants. The difference cannot be attributed to differences in the prevalence of ABO blood groups between the two races. Policies of early discharge of newborns could be affected by the finding that ABO erythroblastosis is two to three times as common in black infants as in white infants.  相似文献   
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The histochemical localization of carbohydrates and lipids and some oxidative, hydrolytic and steroid-linked enzymes has been studied in the testis of the camel with particular reference to the effect of the season on the distribution of these substances. PAS-positive, but diastase-resistant, material was seen mainly in the wall of blood vessels and in the boundary tissues of the seminiferous tubules, tubuli recti and rete testis. Clear cyclical changes were seen for glycogen in the lining epithelium of the seminiferous tubules. Glycogen was most abundant in early stages and very scanty or absent in the late stages of the cycle of the seminiferous epithelium. Numerous small lipid droplets were seen in the interstitial cells and towards the lumen of the seminiferous tubules that contain elongate spermatids or spermatozoa. Large lipid droplets were also demonstrable in the basal layer of the seminiferous epithelium and in the cytoplasmic debri. Alkaline phosphatase was demonstrated in the boundary tissues of the seminiferous tubules, tubuli recti and reti testis and in the cells bordering the lumen of the seminiferous tubules. Succinate and lactic dehydrogenases showed similar patterns of distribution in the interstitial elements and intratubularly. delta5-3beta hydroxysteroid dehydrogenase was exclusively demonstrated in the interstitial cells. 17beta-hydroxysteroid dehydrogenase could not be demonstrated. The season seems to have no effect on the distribution of all these substances. The possible significance of all these findings is discussed.  相似文献   
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Filtration efficiency of Ni(II) from aqueous solution using pristine and modified MWCNTs filters was investigated as a function of Ni(II) ion concentration, pH, and filter mass. MWCNTs were synthesized by CVD method and modified using two complementary treatments, purification (using a mixture of hydrochloric acid and hydrogen peroxide) and functionalization (using nitric acid). The effect and mechanism of each treatment on the structural integrity of pristine MWCNTs has been studied. Morphology of the pristine and modified filters was investigated by Raman Spectrometry (RS), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Fourier Transform Infrared (FTIR) spectrometry and Thermogravimetric analysis. It was found from Raman spec-tra that the ratio of the intensity of D-band to that of G-band decreased by purification process, and increased by functionalization process. The adsorption mechanism of Ni(II) onto the surface functional groups of modified MWCNTs was confirmed by FTIR spectrum. The filtration results showed that the removal efficiency of Ni(II) is strongly dependent on pH and could reach 85%at pH=8. Also, modified MWCNT filters can be reused through many cycles of regeneration with high performance. Functionalized MWCNTs filters may be a promising adsor-bent candidate for heavy metal removal from wastewater.  相似文献   
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