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321.
Zhao L Gattás-Asfura KM Xu J Patel RA Dadlani A Sillero-Mahinay M Cushmore M Rastogi VK Shah SS Leblanc RM 《Chemical communications (Cambridge, England)》2011,47(25):7242-7244
A direct conjugation of organophosphorus acid anhydrolase (OPAA) with CdS quantum dots was prepared via arrested precipitation within the enzyme matrix. The bio-conjugate was found not only to retain enzyme conformational structure but also to retain enzyme activity and be effective at detecting diisopropyl fluorophosphate (DFP) at the micro molar level. 相似文献
322.
Rastogi VK Palafox MA 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(5):970-977
The FT-IR and FT-Raman spectra of 5-Fluorouracil were recorded in the solid phase in the regions 400-4000 cm(-1) and 50-4000 cm(-1), respectively. The vibrational spectra were analysed and the observed fundamentals were assigned to different normal modes of vibration. The experimental wavenumbers were compared with the scaled vibrational values using DFT methods: the Ar matrix data were related to gas phase calculations, while the values of the solid state spectra were compared to those with dimer simulations. The study indicates that some features that are characteristic of vibrational spectra of uracil and its derivatives are retained in the spectrum of 5-fluorouracil and it exists in ketonic form in the solid phase. The tautomerism was also studied and the spectra of the two most stable forms were simulated. The calculated wavenumbers have been employed to yield thermodynamic properties. 相似文献
323.
Among various high-temperature organic polymers, the aromatic polyamides have shown excellent thermal stability due to the stiffness of the polymer chain and hydrogen bonding of the amide groups, but had limited solubility in most organic solvents [1-3]. 相似文献
324.
FT-IR and Raman spectra of the nonlinear optical material l-Valine Hydrobromide crystal have been recorded and analyzed. The equilibrium geometry, bonding features and the harmonic vibrational wavenumbers of LVB have been calculated with the help of density functional theory (DFT) calculation. The lowering of NH stretching wavenumber indicates the formation of NH?Br hydrogen bonding. The calculated First order hyperpolarizability value shows that LVB is the potential candidate for the NLO applications. The electronic effects and the hydrogen bonding were explained using natural bond orbital analysis. 相似文献
325.
Dmitry M. Rein Liron Shavit Rafail L. Khalfin Yachin Cohen Ann Terry Sanjay Rastogi 《Journal of Polymer Science.Polymer Physics》2004,42(1):53-59
The effect of pressure on phase transformations of ultradrawn ultra-high-molecular-weight polyethylene (UHMWPE) fibers was examined by in situ X-ray diffraction measurements with synchrotron radiation. The mesomorphic hexagonal phase was metastable even at a relatively low pressure of about 100 bar. The effect of pressure on the melting transitions was larger than in chain-folded structures. The existence and metastability of the hexagonal phase is the basis of compaction technology of UHMWPE fibers in composite materials. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 53–59, 2004 相似文献
326.
R. G. Rastogi 《Proceedings Mathematical Sciences》1958,47(2):65-76
The results of vertical ionospheric soundings at Ahmedabad during the partial (magnitude 47%) solar eclipse on 14th December 1955 are discussed. The critical frequency of the E layer on control days varied according to the lawf oE=kcos n X, k andn having the mean values 4·06 Mc./s. and 0·37 respectively. The variation off oE during eclipse period was roughly consistent with that of Chapman Layer with a recombination coefficient of about 0·8 × 10?8 cm.3 sec.?1 The critical frequencies of E1, E2 and F1 layers decreased during eclipse, though the variations were irregular. The percentage deviation off 0F2 on the eclipse day from the control day values showed a minimum at about the middle of the eclipse period. There were indications of the formation off 1·5 during the latter part of the eclipse. Semi-thickness of the F2 layer had increased during the eclipse period. Sporadic E layer was not affected by the eclipse. 相似文献
327.
A simple TLC method has been developed for the simultaneous determination of heraclenin and heraclenol in the roots of Heracleum candicans D.C. The analytes were separated on silica gel F254 plates with toluene:ethyl acetate (7:3) and scanned using densitometry at 366 nm. The method was validated in terms of precision,
repeatability and accuracy. The linear range for heraclenin was found to be 4 - 10 μg per spot with correlation coefficient
of 0.997 while for heraclenol it was 1–5 μg per spot with a correlation coefficient of 0.985. The two compounds were quantified
in different samples of H. candicans and were found to be present in the range of 1.02 – 1.36% and 0.29 – 0.43% w/w. The method was found to be very simple, accurate, precise and economical and can be used for routine quality control. 相似文献
328.
Rastogi SK Gibson CM Branen JR Aston DE Branen AL Hrdlicka PJ 《Chemical communications (Cambridge, England)》2012,48(62):7714-7716
A lateral flow test strip assay, enabling sensitive detection of DNA specific to the foodborne pathogen E. coli O157:H7, is described. The use of LNA-conjugated gold nanoparticle probes, along with signal amplification protocols, results in minimum detectable concentrations of ~0.4 nM. 相似文献
329.
330.