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41.
Journal of Solid State Electrochemistry - We report the studies on composite gel polymer electrolytes (GPEs) comprising 0.5 M solution of sodium trifluoromethane sulfonate (Na-triflate or...  相似文献   
42.
In this article, we present a novel approach to throughput enhancement in miniaturized microfluidic microscopy systems. Using the presented approach, we demonstrate an inexpensive yet high-throughput analytical instrument. Using the high-throughput analytical instrument, we have been able to achieve about 125,880 cells per minute (more than one hundred and twenty five thousand cells per minute), even while employing cost-effective low frame rate cameras (120 fps). The throughput achieved here is a notable progression in the field of diagnostics as it enables rapid quantitative testing and analysis. We demonstrate the applicability of the instrument to point-of-care diagnostics, by performing blood cell counting. We report a comparative analysis between the counts (in cells per μl) obtained from our instrument, with that of a commercially available hematology analyzer.  相似文献   
43.
Novel palladium(II)‐N‐(2‐pyridyl)‐N′‐(5‐R‐salicylidene) hydrazine triphenylphosphine complexes were synthesized and characterized by UV, IR, 1H NMR and 31P NMR spectral analysis, C, H, N analysis and magnetic susceptibility measurements. The complexes were effective in the catalytic oxidation of primary and secondary alcohols in presence of N‐methyl‐morpholine‐N‐oxide as oxidant. The oxidation reactions were carried out in dichloromethane. A mechanistic study of the above reactions has been proposed. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
44.
    
Chemical graph theory assumes an imperative part in displaying and planning any chemical structure or chemical network. The molecular structure of a chemical molecule strongly relates to its properties. The graphs that make up the molecular structure are made up of units known as vertices, and the covalent bonds that connect them are known as edges. The topological indices of any chemical compound can be used to better understand the chemical structure and its biological characteristics. In this study, the degree-based multiplicative topological indices of the crystalline structure of cubic carbon (CCS) for levels m = 3–10 are computed, CCS[m] being one of the precious carbon allotropes.  相似文献   
45.
    
In this work, the effect of humidity on WO3 thin films is studied. Two thin films of higher and lower oxidation states are characterized and studied for their interaction with water molecules on the metal oxide sensing surface. The film with higher oxidation is found to be more immune to humidity effect and hence, further used to reduce the same effect using absorbent filters and Nichrome deposited heater mesh. With the use of a Nichrome heater mesh, by increasing mesh temperature from 30 to 90 °C, there is a 63% reduction in absolute humidity at the sensor die. This in turn stabilizes the NO2 sensor response, by decreasing the humidity dependent (40% RH to 90% RH) peak current variation for 3 ppm NO2 exposure, from 65% to 26%. High-temperature ageing at a temperature of 90 °C and 90% RH is found to be effective in significantly reducing humidity effect on sensor current output and only 8.4% change in peak current is observed for 3 ppm NO2 at variable humidity, which stabilizes the sensor current drift due to humidity variation.  相似文献   
46.
An aqueous solution ofbis-2-pyridyl glycol forms a deep blue water-soluble complex with an aqueous solution of copper (II) salts. The complex has an absorption maximum at 600–650 mµ between pH range 3·0–8·7. The complex is stable for four days and obeys Lambert-Beer’s law in the concentration range of 5·08–50·80 ppm. of copper (II) in solution. The optical density of the complex remains constant between pH 3·8–5·9. The molar composition as determined by the method of continuous variation and by the slope ratio method has been found to be 1:1. The limits of interference due to some foreign ions during the estimation of copper (II) have been determined.  相似文献   
47.
We describe here a novel method of generating large volumetric heating in a liquid. The method uses the principle of ohmic heating of the liquid, rendered electrically conducting by suitable additives if necessary. Electrolysis is prevented by the use of high frequency alternating voltage and chemically treated electrodes. The technique is demonstrated by producing substantial heating in an initially neutral jet of water. Simple flow visualisation studies, made by adding dye to the jet, show marked changes in the growth and development of the jet with heat addition.Also with National Aeronautical Laboratory, Bangalore 560 017, India  相似文献   
48.
49.
Horseradish peroxidase (HRPO) was used as a probe to quantitate aflatoxin B1 by a homogeneous immunoassay. The conjugation of AFB1 to HRPO resulted in 54% loss of enyzme activity. In the presence of AFB1 specific antibodies, the HRPO-AFB1 conjugate showed reversal of its lost enzyme activity by 12%. This positive modulatory effect of antibody on the enzyme activity was used as an analytical tool to quantitate AFB1. The homogeneous assay carried out with free AFB1 and HRPO-AFB1 conjugate in the presence of antibodies indicated poor linearity as compared to the heterogeneous assay. It was observed that the number of HRPO-lysine residues involved in AFB1 conjugation were 6–8. The low level of modulation of enzyme activity by antibody with respect to HRPO-AFB1 conjugate, could possibly be attributed to the limited number of lysine residues in the HRPO molecule and its proximity to the active site of the enzyme. Thus, HRPO was found to be limiting as an enzyme with respect to the homogeneous enzyme immunoassay for AFB1 analysis. The antibodies raised were specific for AFB1, and showed excellent linearity even at high dilution for the detection of AFB1 by ELISA indicating that antibodies per se were not the limiting factor.  相似文献   
50.
The case of a particle moving along a nonsmooth constraint under the action of uniform gravity is presented as an example of indeterminancy in a classical situation. The indeterminacy arises from certain initial conditions having nonunique solutions and is due to the failure of the Lipschitz condition at the corresponding points in the phase space of the equation of motion.  相似文献   
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