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91.
92.
Lyoluminescence studies have acquired considerable significance in recent years due to its potential as a cheap, convenient and versatile method for radiation dosimetry. It has advantages over other conventional techniques due to tissue equivalence of organic lyoluminescent materials and small size in which this type of dosimeter can be used. It is particularly attractive for therapeutic dosimetry. The paper reports the performance of glucose crystallised with known concentrations of sensitizer luminol. It also gives the relative performance of various lyoluminescence materials of similar type being studied currently. 相似文献
93.
94.
Surya Kant Mishra 《Proceedings Mathematical Sciences》1964,59(1):21-48
We consider the propagation of sound pulses due to a line source in the inhomogeneous, semi-infinite mediumy ≥ 0 with the boundary conditionφ=0 or?φ/(?y)=0 aty=0, whereφ is the acoustic velocity potential. We suppose that the velocity of wave propagation,c, is given byc ?2=p ?qe ?ay , wherep, q, α are real and positive andp>q. The method of dual integral transformation is used. The solution in terms of pulse propagation modes yields the diffracted pulse and the method of steepest descents gives the geometrical acoustic field. 相似文献
95.
Mishra S. P. Misra K. D. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1978,6(4):355-359
Two dimensional transverse Kelvin-Helmholtz (K-H) instability has been studied at the interface between the two fluids (plasma medium) of finite thickness in relative motion to each other. The perturbations on the interface are assumed to be electromagnetic and a dispersion relation is obtained. The interface (boundary) has been found to be unstable for a wide range of perturbation wavelengths (wave numbers kx, ky). It is shown that the modification introduced by electromagnetic (quasi-electrostatic) perturbations in comparison to electrostatic one is to reduce the growth rate of perturbations. The growth rate maximizes when kx = ky. The applications of this study have been discussed to explain some of the observed ionospheric (auroral arc formation) and magnetospheric (unstable magnetopause boundary, hydromagnetic pulsations) phenomena. 相似文献
96.
The laser Raman spectrum of tere-phthalaldehyde powder has been recorded on a Jobin Yvonhg 2S spectrophotometer with a~100 mW Argon-Ion laser. The infrared spectrum of the solid substance has been recorded on a Perkin-Elmer
621 spectrophotometer in the region 300–4000 cm-1 using KBr and nujol mull techniques. The observed frequencies have been assigned in terms of the fundamentals, overtones
and combinations assumingD
2h point-group symmetry. 相似文献
97.
The sharp, temperature induced, continuous valence transition in EuPd2Si2 is drastically changed by doping with Sn at the Si site upto 5 at. %. Only a first order valence transition occurs for a 3% Sn doped sample and the 2+ component which survives the valence transition orders magnetically at 4.2 K. No valence transition at all occurs for a 5% Sn doped sample right up to 1.9 K and magnetic ordering sets in around 30 K. 相似文献
98.
The aggregation/deaggregation of chlorin p6 with the surfactants CTAB, SDS, and TX 100 have been studied by using absorption, fluorescence, and light scattering techniques. The ionic surfactants are found to cause aggregation of fluorophore at submicellar concentrations. The aggregates dissolve at higher surfactant concentrations to yield micellized monomers. This is rationalized by the interplay of electrostatic and hydrophobic effects. A prominent pH effect is observed in the ionic surfactant induced aggregation process as the charge on the fluorophore is controlled by the pH of the medium. Interestingly, the neutral TX-100 also induces aggregation of chlorin p6 at low concentrations, indicating that hydrophobic effects by themselves can cause aggregation unless there is a hindrance by repulsive electrostatic effects. 相似文献
99.
A.K.?Dharmadhikari A.S.?Sandhu J.A.?Dharmadhikari A.?Mishra G.R.?KumarEmail author 《Applied physics. B, Lasers and optics》2004,79(2):235-238
We report on the investigation of two-photon absorption (TPA) in 4-Diethylamino-N-Methyl-4-Stilbazolium Tosylate (DEST) with 40 picosecond, 1064 nm linear and circular polarization laser radiation. The TPA cross-section 2 measured is larger for linear polarized radiation (948 GM) than that for the circular polarized radiation (840 GM). The large TPA cross-section of DEST facilitates highly directional and efficient TPA induced upconverted emission in the range of 590–640 nm even though the fluorescence efficiency of DEST is very low (0.5%). The net single pass efficiency of upconversion is 7%. PACS 42.65.-k; 42.70.Jk 相似文献
100.
Bachhawat P Mishra S Bhatia Y Bisaria VS 《Applied biochemistry and biotechnology》2004,118(1-3):269-282
The biosynthetic activity of yeast Pichia etchellsii β-glucosidase II (BglII) expressed in recombinant Escherichia coli was utilized for synthesis of cellooligosaccharides, alkyl and terpene glucosides. Cellooligosaccharides with a degree of
polymerization of 3 and greater were resolved by thin-layer chromatography (TLC) using an ethyl acetate: 1-propanol:2-propanol:water
(8:5:1:1) solvent system followed by visualization with 0.2% naphthoresorcinol reagent. Using 2M cellobiose and 15 IU of partially purified BglII, 57 mmol/L of oligosaccharides (comprising mostly cellotriose and cellopentaose) was synthesized in 16 h. Similarly, alkyl
glucosides with chain lengths from 6 to 10 carbons were synthesized and products extracted to near purity by ethylacetate
extraction. The same extraction method was employed to separate, to near purity, various monoterpenyl (nerol, geraniol, citronellol)
glucosides. A reliable and simple method for separation of cellooligosaccharides using a combination of Bio-Gel P-2 gel filtration
and charcoal celite adsorption chromatography was developed. The cellooligosaccharides were separated to purity as confirmed
by TLC. The enzyme was among the very few that could synthesize a wide variety of glycoconjugates. 相似文献