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31.
In this paper an alternative approach for measurement of στ product for 4
F
3/2→4
I
11/2 transition of Nd3+ doped YVO4 crystal is reported. In this method a microchip laser is formed by keeping a small piece of the sample in plane-plane resonator
and a diode laser (808 nm) is used for pumping. The pump power induced thermal lensing effect is used to make the cavity stable.
The cavity mode area is estimated by measuring the thermal lens focal length at the threshold and the average pump area is
measured by Gaussian fit to the intensity profiles of the pump beam. The value of στ product of Nd:YVO4 crystal obtained by this method is within 10% of the reported values. The advantage of this method is that it is a simple
method for direct measurement of στ product of laser crystals. 相似文献
32.
Fusion of the eight vertex SOS model 总被引:4,自引:0,他引:4
Etsuro Date Michio Jimbo Tetsuji Miwa Masato Okado 《Letters in Mathematical Physics》1986,12(3):209-215
A higher spin analogue is presented of the eight vertex-SOS correspondence in the sense of Andrews-Baxter-Forrester. The resulting hierarchy of solvable models contain the hard hexagon model and its recent multi-state generalizations. 相似文献
33.
We consider the quantum mechanics of an electron confined to move on an infinite cylinder in the presence of a uniform radial magnetic field. This problem is in certain ways very similar to the corresponding problem on the infinite plane. Unlike the plane however the group of symmetries of the magnetic field, namely, rotations about the axis and the axial translations, is not realized by the quantum electron but only a subgroup comprising rotations and discrete translations along the axial direction, is. The basic step size of discrete translations is such that the flux through the ‘unit cylinder cell’ is quantized in units of the flux quantum. The result is derived in two different ways: using the condition of projective realization of symmetry groups and using the more familiar approach of determining the symmetries of a given Hamiltonian. 相似文献
34.
35.
An HPTLC method has been developed that coelutes both the isomers of cefpodoxime proxetil (CFP). CFP was chromatographed on a silica gel 60 F254 TLC plate using toluene:acetonitrile (6:4) as a mobile phase and was quantified at 234 nm. The method was validated with respect to linearity, accuracy, precision and specificity. The limit of detection and limit of quantification for CFP were found to be 0.150 and 0.4 μg spot−1, respectively. The proposed method was successfully used to determine the amount of CFP present in the marketed tablets and self-nanoemulsifying systems.
相似文献36.
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38.
Formation and concomitant Michael reaction of 1,3-bis(trimethylsiloxy)isoindoles have been achieved by the reduction of phthalimides with a Zn-Me3SiCl-lutidine system in the presence of α, β-unsaturated carbonyl compounds under sonication. 相似文献
39.
M Takeda H Inoue K Noguchi Y Honma K Okamura T Date S Nurimoto M Yamamura S Saito 《Chemical & pharmaceutical bulletin》1992,40(5):1186-1190
Several N-substituted C-normorphinans (VIII and IX) were synthesized and tested for their analgetic and narcotic antagonist activities and physical dependence capacity. Treatment of N-formyl- octahydro-2-pyrindine (IIIc) with polyphosphoric acid readily gave N-formyl-C-normorphinan (IV). The N-nor bases (V and VII) obtained from IV were converted to VIII and IX. The N-methyl derivative (I), which was previously reported to be inactive by Haffner's method, exhibited potent analgetic activity by the hot plate method and the AcOH-induced writhing test. Compounds VIII and IX showed pharmacological properties similar to those of N-substituted morphinans and exhibited agonist (analgetic) and/or narcotic antagonist activities. The C-nor analogue (IXa) of cyclorphan (IIc) exhibited potent analgetic and antagonist activities with no physical dependence capacity in the single-dose suppression tests both in rats and monkeys. 相似文献
40.
This paper reformulates the classical problem of cash flow valuation under stochastic discount factors into a system of linear equations with random perturbations. Using convergence results, a sequence of uniform approximations is developed. The new formulation leads to a general framework for deriving approximate statistics of cash flows for a broad class of models of stochastic interest rate process. We show applications of the proposed method by pricing default-free and defaultable cash flows. The methodology developed in this paper is applicable to a variety of uncertain cash flow analysis problems. 相似文献