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111.
A study of theEXAFS associated with theK x-ray absorption discontinuity of germanium in pure germanium and in the rare-earth germanides RGe2 (where R=La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er and Y) has been carried out. The Ge-Ge distances have been obtained in these
compounds. Considering the phase to the RGe2 system, the bond lengths in these compounds have been determined. The values obtained by us for the RGe2 compounds (R=La, Ce, Pr, Nd, Sm, Gd, Dy and Y) agree with those obtained earlier by crystallographic methods. The bond lengths
for the compounds TbGe2, HoGe2 and ErGe2 are also being reported. 相似文献
112.
113.
114.
M. D. Deshpande Ravindra Pandey Miguel A. Blanco Arun Khalkar 《Journal of nanoparticle research》2010,12(4):1129-1136
We report the magnetic properties of small Ni13-nAln\hbox{Ni}_{13-n}\hbox{Al}_n clusters with n = 0–13 calculated in the framework of density functional theory. The cluster magnetic moment decreases with the sequential
substitution of Ni by Al atoms, which can be attributed to a greater degree of hybridization that forces the pairing of the
electrons in the molecular orbitals of Ni and Al. For Ni7Al6, the complete quenching of the cluster magnetic moment appears to be due to the antiferromagnetic alignment of atomic spins
as revealed by the spin density plots. 相似文献
115.
A. B. Thomas A. A. Chaudhari R. K. Nanda L. P. Kothapalli U. B. Chavan A. D. Deshpande 《Chromatographia》2009,69(11-12):1485-1487
The simultaneous determination of enalapril (Ena) and losartan (Los) in solid dosage forms were done by two methods. The first method involves spectrophotometric determination using the simultaneous equation method at 222 and 250 nm for Ena and Los, respectively. The second method involved an RP-LC method of analysis using methanol:water:acetonitrile (45:35:20% v/v) as the mobile phase. Both methods were satisfactorily validated as per ICH guidelines. 相似文献
116.
John H. Lehman Rohit Deshpande Paul Rice Bobby To Anne C. Dillon 《Infrared Physics & Technology》2006,47(3):246-250
Carbon multi-wall nanotubes (MWNTs) were grown on a lithium niobate (LiNbO3) pyroelectric detector with a nickel film as the catalyst by hot-wire chemical vapor deposition (HWCVD). Two detectors are documented, each with slightly different deposition conditions. The absolute spectral responsivity of each device was measured from 600 nm to 1800 nm and indicates that the MWNT-coating absorptance is spectrally uniform, with variations of only a few percent. We also discuss growth of MWNTs on LiTaO3 by CVD and the limitations presented by the Curie temperature of the pyroelectric material. 相似文献
117.
Couplings between standard model particles and unparticles from a nontrivial scale invariant sector can lead to long range forces. If the forces couple to quantities such as baryon or lepton (electron) number, stringent limits result from tests of the gravitational inverse square law. These limits are much stronger than from collider phenomenology and astrophysics. 相似文献
118.
119.
Effects of various diol chain extenders on thermal, mechanical, and viscoelastic properties of polyurethanes are discussed. Elastomers were prepared by using polyester (polyethylene-co-propylene adipate), toluene-2,4-diisocyanate, and α,ω-aliphatic diols. The properties imparted by the extenders are explained on the basis of the number of methylene carbons in the extenders. Butanediol-extended polymer showed superior properties, which are ascribed to regularity in the backbone chain of the polymer and ease of formation of hydrogen bonds. 相似文献
120.
Our continued interest in the total synthesis of natural and unnatural antitumor anthracyclines1 especially the aglycones such as daunomycinone (1)2 and 4-demethoxydaunomycinone (2),3 11-deoxydaunomycinone(3)4 and 4-demethoxy-11-deoxydau-nomycinone (4)5 led us to investigate various methods for obtaining these products. Recently we have reported the synthesis of 4-demethoxy-7, 11-dideoxydaunomycinone (5) from 5-methoxy-1-tetralone. Now we wish to report the synthesis of 5 starting from 5-methoxy-1-tetralone (9) which was prepared from 1,6-dimethoxy-naphthalene(8). Umezawa7 et al. have reported the total synthesis of 4-demethoxy-ll-deoxydaunomycin(6) and 4-demethoxy-11-deoxy-adriamycin (7) from 5-methoxy-2-tetralone. 相似文献