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51.
Let G be a graph and v be any vertex of G. Then the neighborhood contracted graphGv of G, with respect to the vertex v, is the graph with vertex set V ? N(v), where two vertices u,wV ? N(v) are adjacent in Gv if either w = v and u is adjacent to any vertex of N(v) in G or u,w ? N[v] and u,w are adjacent in G. The properties of the neighborhood contracted graphs are discussed in this paper. The neighborhood contraction in some special class of graphs, the domination in a graph and the neighborhood contracted graphs are discussed in the paper.  相似文献   
52.
Individuals with diabetic foot ulcers have overlapped the inflammatory, proliferative and remodeling phase, making the tissue vulnerable to delayed healing responses. We aimed to establish the dose–response relationship of photobiomodulation therapy of different doses and matrix metalloproteinases in the healing dynamics of diabetic neuropathic ulcers. Diabetes was induced in 126 Albino Wistar rats, and neuropathy was induced to the hind paw by a sciatic nerve injury method. An excisional wound was created on the neuropathy-induced leg. Photobiomodulation therapy of dosages 4, 6, 8, 10, 12 and 15 J cm−2 and wavelength 655 nm and 808 nm was irradiated. Photobiomodulation therapy of dosages 4, 6 and 8 J cm−2 showed better wound healing properties with optimized levels of matrix metalloproteinases-1 and 8. We observed a strong dose response in the experimental group treated with 6 and 8 J cm−2. The findings from the present study conclude that photobiomodulation therapy of dosages 4, 6 and 8 J cm−2 is suggestive of usefulness in diabetic neuropathic ulcer healing. Markers like matrix metalloproteinases may give a clear direction on response to the therapy. Based on the findings from the present study, we recommend to validate the findings for safety and efficacy in future through human prospective randomized controlled clinical trials.  相似文献   
53.
Iyer CS  Kamath VA 《Talanta》1980,27(6):537-540
The determination of niobium at levels of 0.01% and below is required in certain specifications for stainless-steel welding electrodes, containing 2-3% molybdenum and 0.01% titanium. A method has been developed, based on initial extraction of niobium thiocyanate into butyl acetate followed by stripping with fluoride and re-extraction of niobium thiocyanate after masking of the fluoride by addition of boric acid. The absorbance of the extract is measured at 385 nm. Mo, Ti, V and W can be tolerated at 50 times the concentration of Nb. For higher amounts of Mo, corrections can also be applied. Ta should, however, be restricted to ten times the Nb level. Precision and accuracy of the method are satisfactory. The time taken for an individual determination is about an hour. The method is applicable to mild, low-alloy, stainless and niobium-stabilized steels.  相似文献   
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Activation energy for the curing process of epoxy glass mica tape has been experimentally determined from differential scanning calorimetric measurements and found to be 20 kcal/ mol. Thermochemical calculation shows that the rate controlling step is the dissociation of the C-O bond in the epoxide leading to ring opening and its subsequent reaction with amine hardener. Shelf life has been determined from the measurement of the enthalpy loss corresponding to the curing during the aging process. The kinetics of the aging process also yields an activation energy of 20 kcal/mol which corresponds to the slow curing of the epoxy resin.  相似文献   
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Optical diagnostics of laser-produced plasma requires a coherent, polarized probe beam synchronized with the pump beam. The probe beam should have energy above the background emission of plasma. Though the second harmonic probe beam satisfies most of the requirements, the plasma emission is larger at the harmonic frequencies of the pump. Hence, at high intensities we need a probe beam at non-harmonic frequencies. We have set up a Raman frequency shifted probe beam using a pressurized hydrogen cell that is pumped by the second harmonic of the Nd glass laser that operates at only one Stokes line of 673.75 nm.  相似文献   
58.
A new force field for dimethyl ether (DME) based on the Lennard-Jones (LJ) 12-6 plus point charge functional form is presented in this work. This force field reproduces experimental saturated liquid and vapor densities, vapor pressures, heats of vaporization, and critical properties to within the statistical uncertainty of the combined experimental and simulation measurements for temperatures between the normal boiling and critical point. Critical parameters and normal boiling point are predicted to within 0.1% of experiment. This force field is used in grand canonical histogram reweighting Monte Carlo simulations to predict the pressure composition diagrams for the binary mixtures DME + SO(2) at 363.15 K and DME + CO(2) at 335.15 and 308.15 K. For the DME + SO(2) mixture, simulation is able to qualitatively reproduce the minimum pressure azeotropy observed experimentally for this mixture, but quantitative errors exist, suggesting that multibody effects may be important in this system. For the DME + CO(2) mixture, simulation is able to predict the pressure-composition behavior within 1% of experimental data. Simulations in the isobaric-isothermal ensemble are used to determine the microstructure of DME + SO(2) and DME + CO(2) mixtures. The DME + SO(2) shows weak pairing between DME and SO(2) molecules, while no specific pairing or aggregation is observed for mixtures of DME + CO(2).  相似文献   
59.
Novel CoII, NiII, CuII and ZnII complexes of the polynucleating oxaza macrocyclic ligand (LH4) derived from the 2:2 condensation of pyrazole-3,5-dicarbohydrazide and 2,6-diformyl-4-methylphenol have been synthesized. Ligand and complexes were characterized on the basis of elemental analysis, IR, 1HNMR, UV–Visible, magnetic susceptibility, ESR and conductivity measurements, FAB-mass and thermal analysis. Present ZnII and CuII complexes are binuclear in nature with octahedral geometry, where as CoII and NiII complexes are tetranuclear with square-planar geometry. CuII and CoII complexes are paramagnetic whereas ZnII and NiII complexes are diamagnetic. Only the copper complex has shown redox property in the applied potential range while the ligand and other complexes are found to be electrochemically innocent.  相似文献   
60.
Cathodic reduction of zinc nitrate solution results in the deposition of ZnO crystallites with a strong c-axis orientation. The orientation of crystallites can be switched to 10l (l?=?1, 2, 3) direction by varying the bath concentration (0.04–0.1?M) and the deposition conditions (T, 50–70?°C; t, 30–90?min). The range of concentrations yielding c-axis orientation can be widened at a high deposition temperature. At 0.1?M bath concentration and long deposition times, crystallites are oriented along 10l (l?=?3) direction. At low temperature (50?°C), 100 oriented nanostructured ZnO coatings are obtained (crystallite size, 20–35?nm). The c-axis-oriented crystallites grow as hexagonal columns perpendicular to substrate and 10l-oriented crystallites grow tilted at different angles to the substrate surface.  相似文献   
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