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排序方式: 共有78条查询结果,搜索用时 10 毫秒
1.
Mg
x
Zn1-x
O films with 0.15 mole composition of Magnesium were successfully deposited by the spin coating sol–gel method. Zinc acetate
dihydrate and Magnesium acetate were used as starting precursors to prepare the solution in ethanol solvent. The MgZnO films
were deposited on microscopic glass substrates and post annealed at three different temperatures. X-ray Diffractometer (XRD),
Scanning Electron Microscopy (SEM) and UV–VIS Spectrophotometer were used to characterize the deposited films for studying
structural and optical properties. Energy dispersive analysis by X-ray (EDAX) was used to determine incorporation of Mg content
in ZnO films. XRD spectrum reveals that, the deposited Mg doped ZnO films were polycrystalline in nature. The intensity of
c-axis in the XRD spectrum goes on decreasing as Mg composition slightly increasing corresponding to increase in annealing
temperature. EDAX spectra clearly showed the incorporation of Mg into the ZnO films. Semiconductor characterization system
was used for the I–V characterization of MgZnO films. I–V characteristics show decrease in current as increase in the biased
voltage. Optical band gap of MgZnO films was found to be increased from 3.2 to 3.38 eV as estimated from the absorption coefficients. 相似文献
2.
Sachin R. Shirsath Anup P. Patil Rohit Patil Jitendra B. Naik Parag R. Gogate Shirish H. Sonawane 《Ultrasonics sonochemistry》2013,20(3):914-923
The present work deals with the removal of Brilliant Green dye from wastewater using a poly(acrylic acid) hydrogel composite (PAA-K hydrogel) prepared by incorporation of kaoline clay. The composite has been synthesized using ultrasound assisted polymerization process as well as the conventional process, with an objective of showing the better effectiveness of ultrasound assisted synthesis. It has been observed that the hydrogel prepared by ultrasound assisted polymerization process showed better results. The optimum conditions for the removal of dye are pH of 7, temperature of 35 °C, initial dye concentration of 30 mg/L and hydrogel loading of 1 g. The extent of removal of dye increased with an increase in the contact time and initial dye concentration. A pseudo-second-order kinetic model has been developed to explain the adsorption kinetics of dye on the PAA-K hydrogel. Thermodynamic and kinetic parameters indicate that the adsorption process is spontaneous in nature and the PAA-K hydrogel prepared by ultrasound process is a promising adsorbent compared to conventional process. The obtained adsorption data has also been fitted into commonly used adsorption isotherms and it has been found that Freundlich as well as Langmuir adsorption isotherm models fits well to the experimental results. 相似文献
3.
Amit S. Nagare Arpan Manna Pramod D. Sonawane Anil Kumar 《Journal of Physical Organic Chemistry》2015,28(11):665-673
Prevailing classification of salts based on their effect in solubility and stability of proteins in aqueous solution predicts that tetraalkylammonium salts, guanidinium chloride (GnCl), LiClO4 act as salting‐in (S/I) and LiCl, NaCl act as salting‐out (S/O) in aqueous conditions. In the same context the behaviour of GnCl, LiClO4 and LiCl are contradictory in polar solvents like ethylene glycol and formamide. In these solvents, expected salt effect shows just opposite nature from their usual expectation. However, in the aqueous solution salts like tetraalkylammonium halide (R4NX, R = alkyl group, X = Br group) behave like salting‐in salts. The physicochemical origin of the salting in effect of R4NX type of salts has been discussed elaborately in the present work. The role of cations in terms of substitution of various alkyl groups on R4NX has been systematically presented here on the basis of experimental kinetic and thermodynamic studies. The abnormal behaviour of R4NX salts in aqueous solution has also been explained by the Setschenov equation (ks) and Δμsolvation values, which highlights their individual nature out of common properties of R4NX. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
4.
5.
Ultrasound assisted synthesis of yellow rare earth cerium zinc molybdate anticorrosion nanopigment is presented. This new class of pigment is eco-friendly alternatives to lead, cadmium and chromium pigment as these pigments contains carcinogenic species like Cr6+ which is responsible for human disease. The synthesis of nanosized cerium zinc molybdate was carried out using cerium nitrate, sodium zinc molybdate as a precursor materials by conventional and ultrasound assisted chemical precipitation method without addition of emulsification agent. XRD, FTIR and elemental analysis confirm the formation of cerium zinc molybdate nanoparticles. The conductivity results indicate that conventional synthesis takes longer time, while in sonochemical technique (US), reaction completes within short period of time. Improved solute transfer rate, rapid nucleation, and formation of large number of nuclei are attributed to presence of cavitation. Saturation of the Ce3+ ions reaches earlier in case of sonochemical technique which restricts the growth of particles hence smaller size is obtained. The crystallite size of cerium zinc molybdate was found to be 27 nm from XRD analysis. 相似文献
6.
Sudrik SG Maddanimath T Chaki NK Chavan SP Chavan SP Sonawane HR Vijayamohanan K 《Organic letters》2003,5(13):2355-2358
In situ-generated silver nanoclusters(Ag(n)) during the reduction of either silver(I) oxide or other salts presumably catalyze the Wolff rearrangement of alpha-diazoketones. Their optical, physical, and catalytic properties depend on the starting silver(I) compound and the reaction conditions. [reaction: see text] 相似文献
7.
Reactions of hydroxyl radicals, generated by photodecomposition of hydrogen peroxide in acetonitrile, with a wide variety of cycloalkenes have been examined. The results show that the major reaction is the addition of hydroxyl radicals to the less substituted end of the double bond, furnishing the secondary alcohols. The reactivity pattern and the observed regio- and stereoselectivity clearly reveal that the steric parameters associated with the substrates play a dominant role in directing the addition reactions. More importantly, this study led to the development of a new methodology for the facile conversions of olefins essentially into secondary alcohols, and includes a few examples which demonstrate the potential of the method. 相似文献
8.
Novel [2n]thiacalixarenepyrazine and [2n]thiacalixarenetriazine systems were synthesised by one-pot SNAr reactions. A screening of the metal-complexing ability of [26]hexathiacalix[3]arene[3]pyrazine revealed its affinity for CuI, CuII and AgI metal salts. 相似文献
9.
A new class of non-mesomerically stabilized, unbranched, configurationally stable lithiated alpha-thiocarbanion has been synthesized and its stereospecific reactions with several electrophiles were investigated. 相似文献
10.
The review presents the most elegant and promising set of synthetic routes for the synthesis of 2-aminothiophenes by the Gewald reaction. Applications of this facile methodology to pharmaceuticals and dyestuffs have been demonstrated. 相似文献