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101.
We have developed an experimental method based on the visibility factor of light-scattering minima to obtain size-polydispersity information from contaminants upon a flat substrate. We verify the method by using double-interaction-model calculations and use this technique to examine experimentally the radial variation of a micrometer-sized fiber and the size polydispersity of spherical particles upon a substrate. 相似文献
102.
103.
Prof. Dany Leviatan 《Mathematische Zeitschrift》1972,124(3):208-212
104.
The energy barriers for the addition to ethylene of a series of carbenes have been calculated at an ab initio level. using the STO-3G and 3-21G basis sets. It is shown that the usual extrapolation of experiment results, which predicts that the reactivity of carbenes decreases when increasing its nucleophilic character, is not valid. 相似文献
105.
M. Moreno 《Solid State Communications》1981,38(11):1045-1048
It is argued that in a series of complexes formed by ions of the same type and having the same geometry and ligand the degree of hybridization tends to decrease when covalency increases. This rule which discards any sp2 explanation for the ligand hybridization has been well verified through series of d9 and s1 complexes. The validity of such a rule, also useful for understanding the behaviour of in some D2h systems, outlines that ligand core polarization effects are negligible in these cases. 相似文献
106.
P-Donor nucleophiles of cone angle >or=145 degrees are known to react with Os3(CO)9(mu-C4Ph4) quite differently from those with cone angles 相似文献
107.
Amendola V Rizzi GA Polizzi S Meneghetti M 《The journal of physical chemistry. B》2005,109(49):23125-23128
Gold nanoparticles are synthesized by laser ablation of a gold plate in toluene. The nanoparticles do not show their characteristic surface plasmon absorption (SPA) and are found to be included in a graphitic matrix. The absence of this absorption is found to derive from the presence of the matrix which prevents the growth of large nanoparticles and covers them, suppressing the SPA according to the Mie model for core@shell particles. It is possible to recover the nanoparticle SPA by oxidizing the carbon matrix, obtaining, therefore, some control on the activity of this absorption. 相似文献
108.
We report on direct measurements of the impurity band hole polarization in the diluted magnetic semiconductor (Ga,Mn)As. The polarization of impurity band holes in a magnetic field is strongly enhanced by antiferromagnetic exchange interaction with Mn ions. The temperature dependence of the hole polarization shows a strong increase of this polarization below the Curie temperature. We show that the ground state of the impurity band is formed by uniaxial stress split F=+/-1 states of antiferromagnetically coupled Mn ions (S=5/2) and valence band holes (J=3/2). The gap between the Mn acceptor related impurity band and the valence band is directly measured in a wide range of Mn content. 相似文献
109.
A thin-film optical filter used as a one-dimensional spatial filter is presented, and its design is briefly examined. The filter consists of a stack of quarter-wave dielectric layers upon a right-angle prism that selectively cancel a reflected or transmitted plane-wave front for various angles of incidence. Transmittance and reflectance are low-pass functions or high-pass functions of the angle of incidence with a high degree of steepness. In combination, these filters exhibit bandpass transmittance with a variable bandwidth. Applications to detection of extrasolar planets are briefly discussed. 相似文献
110.
Llobet A Christianson AD Bao W Gardner JS Swainson IP Lynn JW Mignot JM Prokes K Pagliuso PG Moreno NO Sarrao JL Thompson JD Lacerda AH 《Physical review letters》2005,95(21):217002
The heavy fermion system exhibits properties that range from an incommensurate antiferromagnet for small to an exotic superconductor on the Ir-rich end of the phase diagram. At intermediate where antiferromagnetism coexists with superconductivity, two types of magnetic order are observed: the incommensurate one of and a new, commensurate antiferromagnetism that orders separately. The coexistence of -electron superconductivity with two distinct -electron magnetic orders is unique among unconventional superconductors, adding a new variety to the usual coexistence found in magnetic superconductors. 相似文献