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671.
H. M. Agrawal Mohd Wasim M. Afzal Ansari M. L. Sehgal 《Zeitschrift für Physik A Hadrons and Nuclei》1981,300(4):313-314
Cross-section for209Bi(n, α)206Tl reaction at incident neutron energies 340±150 keV and 575±235 keV have been measured to be 1.26±0.18 μb and 1.55±0.23 μb, respectively. The activation technique was used for measuring the cross-sections. These values have been compared with theoretical values based on Hauser Feshbach Statistical Model. 相似文献
672.
A new calixarene hydroxamic acid, 25,26,27,28-tetrahydroxy-5,11,17,23-tetrakis (N-p-chlorophenyl) calix[4]arene hydroxamic acid (CPCHA) is synthesized and used for the extraction and graphite furnace atomic absorption determination of zirconium(IV). The extract is also determined spectrophotometrically as CPCHA-SCN complex having maximum absorbance at 447 nm with molar absorptivity 9.4x10(3) l mol(-1) cm(-1). The Beer's law obeys in the range of 1.0-9.5 ppm of zirconium. The graphite atomic absorption (GFAAS) increases the sensitivity by about 50 folds. The method is applied to the trace determination of zirconium(IV) in standard samples. 相似文献
673.
674.
Line strengthsS for the dipole allowed transitions within then=2 complex of the carbon isoelectronic sequence have been fitted in the formZ
2
S=A+B/(Z–C), whereZ is the nuclear charge of a particular ion. The constantsA,B andC are determined by using a non-linear least square method. The data forS is taken from the configuration interaction calculations which included internal, semi-internal and all external type correlations for ions in the rangeZ=8–26. It is shown that the values ofA obtained from the fit for all the transitions are in excellent accord with the ab-initio values obtained in the hydrogenic limitZ provided near degeneracy effects are included. 相似文献
675.
676.
677.
Summary A new and simple spectrophotometric method for the determination of phorate, also known as Thimet, a widely used systemic insecticide is proposed. The method is based on the oxidation of phorate to sulphones by concentrated sulphuric acid and its hydrolysis under acidic conditions at 100°C to release formaldehyde which is then treated with J-acid to produce a yellow fluorescent color, which has an absorbance maximum at 470 nm. Beer's law is obeyed in the range of 1–8 ppm of phorate. The method has been applied to the determination of phorate in effluent water, rice, wheat and cabbage samples. The method is free from interferences of most of the commonly used pesticides and other common ions. 相似文献
678.
A selective and sensitive method for the extraction and spectrophotometric determination of vanadium(V) in microgram quantities is described. The molar absorptivity of the yellow vanadium(V)-caffeic acid-Aliquat 336 extract is 1.3 x 10(4) 1.mole(-1).cm(-1) at 370nm. The method is compared with the atomic-absorption spectrometric method and applied to the trace determination of vanadium in steel, alloys, a rock and environmental samples. 相似文献
679.
In this work, we investigate the feasibility of teleporting an unknown qudit with unit fidelity and non-unit probability using partially entangled state as a shared resource. We also give an expression for the probability of success for teleportation of an unknown qudit. 相似文献
680.
Mukul Agrawal T. R. Sridhar P. K. Jain B. N. Basu 《International Journal of Infrared and Millimeter Waves》2000,21(8):1255-1267
The gyro-TWT in a cylindrical waveguide of linearly-tapered cross section was analyzed for the gain-frequency response, using the Pierce-type gain equation. The taper in the waveguide cross section was adjusted for wide device bandwidths, either by changing the taper angle, while keeping the interaction length to be constant, or by changing the interaction length, while keeping the initial and final radii of the waveguide constant. Tapering led to the prediction of wide bandwidths, though at the cost of gain, as compared to a non-tapered device. The range of the DC background magnetic flux density relative to its grazing-point value was identified as a crucial parameter for large gains, with appreciable bandwidths, and minimum mode mixing in a tapered device, the latter in general facing more mode competition than a non-tapered device. 相似文献