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101.
Propagation of two-copropagating or counterpropagating beams is considered in a slab of nonlinear dielectric which is in two-photon resonance with respect to the sum of the laser frequencies. The effects of saturated absorption and dispersion of the beam intensities are studied in detail. The slab transmission is shown to be significantly affected by the induced optical Stark-shift. 相似文献
102.
Bal.K. Agrawal 《Solid State Communications》1981,37(3):271-274
A five-atom cluster Bethe lattice method treating the short-range order with proper statistical effects has been proposed for understanding the crystalline and amorphous alloys. Numerical results for Ge1?xSix alloys are in excellent agreement with the experimental data. In the system studied the network is random but the nearest-neighbour coordination should be treated exactly. The long-range coordination is seen to be concentration-dependent in the crystalline alloys but concentration-independent in the amorphous alloys. 相似文献
103.
M. D. Agrawal C. S. Bhandari M. K. Dixit N. C. Sogani 《Monatshefte für Chemie / Chemical Monthly》1976,107(1):75-82
Stability constants of praseodymium chelates of 3,4,5-trihydroxy sodium benzoate are determined by using Bjerrum-Calvin pH titration technique at constant ionic strength 0.1M-sodium perchlorate and at 28±0.1°C. Values calculated by different methods are in good agreement. The study reveals that during complexation only one proton of the ligand molecule is replaced by the metal and oxygen of adjacent phenolic group acts as a coordinating atom. IR and NMR spectral studies of the ligand reveal that one of the OH groups (in meta position to carboxylic group) remains free while two other phenolic groups are involved in intramolecular hydrogen bonding. One water molecule is found attached in crystalline gallic acid.
Mit 2 Abbildungen 相似文献
Mit 2 Abbildungen 相似文献
104.
Condensation of bis(2-furanthiocarboxyhydradatometal(II), M(fth)2; [M (II) = Mn, Fe, Co, Ni, Cu and Zn] with pyridine-2- and -4-carboxaldehydes gave complexes of the formula M(pfth)2 [pfth? = pyridine-2-carboxaldehyde-2-furanthiocarboxyhydrazonato], Ni(Ifth)2, Zn(Ifth)2, Cu(Ifth) and Co(Ifth)3, (Ifth? = pyridine-4-carboxaldehyde-2-furanthiocarboxyhydrazonato). The magnetic and electronic spectral studies coupled with photoacoustic or Mössbauer spectra suggested octahedral geometry for the M(II) complexes with low-spin states for Co(Ifth)3 and Fe(pfth)2. IR and 1H NMR spectral studies of diamagnetic complexes suggested bonding through “azomethine” nitrogen and “thiolo” sulphur. IR spectra also showed the involvement of pyridine ring nitrogen in coordination in all the complexes except Cu(Itfh), Co(Ifth)3, and Zn(Ifth)2. Some of the compounds possessed antimicrobial activity. 相似文献
105.
K. G. Varshney A. Agrawal S. C. Mojumdar 《Journal of Thermal Analysis and Calorimetry》2007,90(3):721-724
Pyridine based thorium(IV) phosphate (PyThP) has been synthesized by drop-wise addition of the thorium(IV) nitrate with constant
stirring into a mixture of pyridine and phosphoric acid. This material has been characterized using X-ray, IR spectra, TG,
DTG and SEM studies in addition to its ion exchange capacity, elution and pH titrations. The material has been found amorphous
and fibrous in nature on the basis of X-ray diffraction and SEM studies. TG has revealed the changes incurred in the material
on thermal treatment and IR spectral studies have shown the presence of various groups in its structure. 相似文献
106.
G. P. Agrawal 《Optics & Laser Technology》1981,13(3):141-144
The atmospheric propagation of a sequence of short, intense laser pulses is considered. The pulses propagate in a self-induced low-density channel, the effectiveness of which depends on a set of three variables. Using a simple model for the laser-atmosphere interaction, the range of successive pulses is determined by numerical solutions to the paraxial wave equation. The dependence of the length, width, and depth of the created channel on the important variables is explored. 相似文献
107.
From a careful examination of the diurnal variation of cosmic ray intensity at high energies and the interplanetary field
characteristics, the average characteristics of diurnal variation were recently explained by us in terms of a balance between
outward convection and field aligned diffusion, the latter arising out of a positive radial density gradient. In this paper,
we extend this new concept to explain the large variability observed in the diurnal variation on a day-to-day basis and further
demonstrate that the measurement of diurnal anisotropy characteristic of cosmic ray particles on a day-to-day basis can be
used directly to infer the nature and scale sizes of interplanetary field parameters. Comparing with the magnetic field vector,
we show that this simple concept holds good on more than 80% of days. On the rest 20% of days which have a predominant morning
maxima, the diurnal anisotropy characteristics seem to indicate the presence of a significant component of transverse diffusion
current in addition to the normal convection and diffusion flow. Such days are found to be present in the form of trains of
consecutive days and are found to be associated with abrupt changes in the interplanetary field direction having scale sizes
>4 hr. The value ofK
⊥/K
‖ which is normally about ⩽0.05 is found to be ≈1.0 on non-field aligned days. 相似文献
108.
109.
110.