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91.
R.M. Mehra P.C. Mathur A.K. Kathuria Radhey Shyam 《Journal of Physics and Chemistry of Solids》1978,39(3):295-298
D.C. conductivity measurements have been made as a function of temperature and external electric field on bulk amorphous selenium. A decrease in the activation energy with increase of electric field has been observed. This has been interpreted in terms of a mixed, thermally activated and trap limited conduction process. 相似文献
92.
Tests are described for differentiation between neutral, basic, and acidic amino acids based on the formation of nickel dimethylglyoxime precipitate from an equilibrium mixture containing Ni2+, dimethylglyoxime and Ni2+, dimethylglyoxime-glycine. A highly sensitive and specific test for lysine is described, based on the formation of nickel dimethylglyoxime precipitate in a drop of the equilibrium mixture, by the reaction of the volatile amino aldehyde, produced by the oxidative deamination-decarboxylation of lysine. Other basic amino acids, i.e., arginine and histidine do not interfere, and the test can be applied for lysine in a mixture with other amino acids. 相似文献
93.
The Nd3+ complexes of β-diketonates have been studied earlier, 1–3 but those of aromatic acids have not been studied in detail. The present communication reports the study of two of such complexes. 相似文献
94.
This report presents details of the development of a new crossed molecular beams apparatus designed and fabricated to carry
out high sensitivity ion translational energy spectrometric investigations of the potential energy surfaces of small molecular
species. The translational energy spectrometer is used to carry out experimental studies of ion-neutral reactions resulting
in charge stripping of CS+ radicals and dissociation of metastable CO2+ dications. These results are interpreted in the light of high-levelab initia molecular orbital calculations of the pertinent molecular potential energy functions. New results for the double ionisation
energy of CS and the kinetic energy released upon dissociation of specific electronic states of CO2+ are presented. 相似文献
95.
Lu Q Keskar G Ciocan R Rao R Mathur RB Rao AM Larcom LL 《The journal of physical chemistry. B》2006,110(48):24371-24376
Density gradient centrifugation is a high-resolution technique for the separation and characterization of large molecules and stable complexes. We have analyzed various nanotube structures by preparative centrifugation in sodium metatungstate-water solutions. Bundled, isolated and acid-treated single-walled nanotubes (SWNTs) and multiwall nanotubes (MWNTs) formed sharp bands at well-defined densities. The structure of the material in each band was confirmed by transmission electron microscopy and Raman spectroscopy. Our data suggest respective densities of 1.87, 2.13, 1.74, and 2.1 g/cm(3) for bundled, isolated, and acid-treated SWNTs and MWNTs. These measured results compare well with their calculated densities. 相似文献
96.
97.
Hanle technique is used for the lifetime measurement of the atomic excited states. Field dependent Hanle signal is Lorentzian under ideal conditions. Any departure from ideal situation is reflected in the shape of the Hanle signal resulting in erroreous measurements. The effect of one such factor, a finite interaction cross section, is discussed here. 相似文献
98.
Abstract The Raman spectra of a crystalline powder of InCl3 and of a de-ionized water solution show the presence of four bands at 300.0, 289.2, 115.6 and 87.1 cm?1, thus suggesting that InCl3 is not a perfectly planar molecule. 相似文献
99.
Specimens of iron-doped indium oxide (In1-xFex)2O3 with x?=?0.015, 0.03, 0.045 and 0.06, amalgamated through a traditional solid-state reaction method followed by H2/air sintering, were characterised using an X-ray diffractometer (XRD), a vibrating sample magnetometer (VSM), and a scanning electron microscope (SEM) to investigate their structural, magnetic and morphological properties respectively. According to XRD plots, all the specimens exhibit cubic bixbyite structures along with ancillary phases. Magnetic assessment showed that In2O3 has a negative susceptibility, exhibiting diamagnetic behaviour at room temperature. The doping of Fe ions induces ferromagnetic (FM) ordering, which is enhanced with increasing doping content. The strength of the magnetisation increases when the specimens are exposed to H2 but is reduced on further air sintering. A bound magnetic polaron (BMP) model is successfully fitted to the observed FM data involving localised carriers and magnetic cations. A multivariate assessment viz. a hierarchical cluster analysis (HCA) was used to corroborate and strengthen the experimental determined magnetic properties. A homogeneous particle distribution was observed in all SEM micrographs and is validated through MATLAB-based simulation by applying a watershed segmentation algorithm. Surface plots also confirm the change in magnetic properties with increase in doping concentration. 相似文献
100.
Arulraj Ruba A. Gajjela Raju Chauthe Siddheshwar Kisan Bagadi Muralidhararao Mathur Arvind 《Chromatographia》2022,85(6):497-506
Chromatographia - In drug discovery environment, determination of residual solvents is indispensable and requires rapid analysis covering a maximum number of commonly used solvents especially with... 相似文献