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1.
Present paper deals with the structural, magnetic and transport studies of as-deposited as well as annealed Co/GaAs(0 0 1) thin film at different temperatures. The X-ray diffraction measurements show oriented growth of as-deposited Co film in the hcp (0 0 2) direction. However, the sample annealed at higher temperatures shows formation of ternary Co2GaAs phase at the interface. Corresponding magnetic and transport measurements show decrement in magnetization and resistivity with annealing temperatures. The observed reductions in magnetization and resistivity values are mainly attributed to the formation of ternary Co2GaAs phase at the interface. 相似文献
2.
Ranjeet Prasad Dash Bhupendrasinh F. Chauhan Sheetal Anandjiwala Manish Nivsarkar 《Chromatographia》2010,71(7-8):609-615
An RP-LC method was developed and validated for comparing the pharmacokinetics profile of Vasa Swaras (leaf juice of Adhatoda vasica Nees., Fam. Acanthaceae) with that of the pure vasicine and vasicinone (chief marker compounds of A. vasica) upon oral administration of Vasa Swaras in rats, and also in different animal groups. Significant difference with p < 0.05 was found in the oral bioavailability of vasicine and vasicinone when administered as Vasa Swaras and as single vasicine and/or vasicinone. Vasicine and vasicinone were found to be more bioavailable from Vasa Swaras than pure vasicine and/or vasicinone. 相似文献
3.
Ranjeet Kumar J. R. Yadav D. D. Rao Lal Chand 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):785-788
Bioassay technique is used for the estimation of actinides present in the body based on their excretion rate through body
fluids. For occupational radiation workers urine assay is the preferred method for monitoring of chronic internal exposure.
Determination of low concentrations of actinides such as plutonium, americium and uranium at low level of mBq in urine by
alpha spectrometry requires pre-concentration of large volumes of urine. This paper deals with standardization of analytical
method for the determination of Pu-isotopes in urine samples using anion exchange resin and 236Pu tracer for radiochemical recovery. The method involves oxidation of urine followed by co-precipitation of plutonium along
with calcium phosphate. Separation of Pu was carried out by Amberlite, IRA-400, anion exchange resin. Pu-fraction was electrodeposited
and activity estimated using tracer recovery by alpha spectrometer. Twenty routine urine samples of radiation workers were
analyzed and consistent radiochemical tracer recovery was obtained in the range 74–96% with a mean and standard deviation
of 85 and 6% respectively. 相似文献
4.
R. Brajpuriya S. Tripathi S.M. Chaudhari D.M. Phase T. Shripathi U. Pietsch 《Applied Surface Science》2007,253(21):8584-8587
In situ temperature dependent energy-dispersive structural and magnetic study of electron beam evaporated Fe/Al multilayer sample (MLS) has been investigated. The structural studies show the formation of an intermixed FeAl transition layer of a few nanometers thick at the interface during deposition, which on annealing at 300 °C transforms to B2FeAl intermetallic phase. Magnetization decreases with increase in temperature and drops to minimum above 300 °C due to increase in anti-ferromagnetic interlayer coupling and formation of nonmagnetic FeAl phase at the interface. The Curie temperature (Tc) is found to be 288 °C and is much less than that of bulk bcc Fe. 相似文献
5.
Ranjeet Brajpuriya Sandeep Rajan Snehal Jani Anupam Vyas 《Surface and interface analysis : SIA》2019,51(3):371-377
Fe-Al alloying is a matter of interest because of its technological importance and many applications. Different growth conditions may lead to different results, ie, formation of various phases. These phases may be magnetic or nonmagnetic in nature. Cosputtering of Fe and Al with magnetron-sputtering setup provides us with a good option of alloying and to study the various phase formations. As, yet now researchers studied the alloying through cosputtering process only in oxygen environment, so a study in nonreactive environment was inevitable and interesting. Therefore, the authors went for Fe-Al thin-film synthesis using the magnetron sputtering in argon environment. Hence, this paper discusses the Fe and Al alloy formation in argon environment and annealed the samples at different temperatures for different time durations so as to allow various phase formations. The samples were characterized with grazing incidence X-ray diffraction (GIXRD), grazing incidence X-ray reflectivity (GIXRR), magneto-optical Kerr effect (MOKE), and atomic force microscopy (AFM) techniques so as to study structural, morphological, and magnetic properties. The results confirm that cosputtering provides better chances of alloying and also supports formation of various stable phases in comparison with other available techniques. 相似文献
6.
Paduraru PM Popoff RT Nair R Gries R Gries G Plettner E 《Journal of combinatorial chemistry》2008,10(1):123-134
We describe methods for the rapid generation of minilibraries of substituted alkoxy benzenes (consisting of 4-5 compounds), for screening as insect olfaction or gustation inhibitors. Synthetic or commercially available monoalkoxy benzene compounds were mixed and reacted with various alkyl halides to afford a first set of minilibraries. A second and third set were generated from allyloxy minilibraries via the Claisen rearrangement and subsequent alkylation of the ortho-allyl phenols. We have chosen to prepare a collection of small libraries (as opposed to one large library) to test the response insects exhibit toward blends of compounds. We demonstrate how our minilibraries can be screened, both against insect antennae and against expressed pheromone-binding proteins from the gypsy moth, Lymantria dispar. 相似文献
7.
Chattopadhyay SK Kumar S Tripathi S Kaur R Tandon S Rane S 《Biomedical chromatography : BMC》2008,22(12):1325-1345
A rapid, sensitive and simple reverse-phase high-performance liquid chromatographic-electrospray ionization-mass spectrometry method for simultaneous determination of cleomiscosin A and cleomiscosin B has been developed and validated. The isomeric coumarinolignoids cleomiscosin A (1) and cleomiscosin B (2) were separated on a Waters symmetry C(18) column with a solvent system composed of acetonitrile-methanol (1:2) and acetic acid-water (0.5:99.5) in a gradient elution mode. The absorption at 326 nm was chosen as the measuring wavelength in which resolution and baseline separation of compounds 1 and 2 could be obtained. The identity of the two isomeric compounds 1 and 2 in the samples were determined on a triple quadrupole mass spectrometer with ESI interface operating in the positive mode. Calibration curves were linear (r(2) > 0.993) over the concentration range 20-200 microg/mL for cleomiscosin A and 10-200 microg/mL for cleomiscosin B with acceptable accuracy and precision, respectively. The intra-day and inter-day precision were 1.13 and 0.82% for cleomiscosin A and 1.78 and 1.28% for cleomiscosin B, respectively. The validated method was successfully applied for the analysis of the above two compounds in different extracts of Cleome viscosa. 相似文献
8.
In the adsorption of linear C1-C8 alkanes, alkenes and alcohols on zeolite chabazite, molecules smaller than 6.7 A are adsorbed in significant amounts, whereas longer chains are almost fully excluded from the micropores. 相似文献
9.
Ranjeet Bairwa 《合成通讯》2013,43(6):943-952
The facile, regiospecific, one‐pot synthesis of 2‐(3,5‐diaryl‐4,5‐dihydro‐1H‐pyrazol‐1‐yl)‐4,6‐diarylpyrimidines derivatives has been described, involving a [3+2] and [3+3] cyclocondensation between the α,β‐unsaturated ketones and aminoguanidine bicarbonate. 相似文献
10.