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41.
Energy values ofK, L
II andL
III levels calculated by the relativistic self consistent field method have been used to compute the energies ofKα
1, 2 lines. These values deviate considerably from the experimental values due to Bearden and Burr. The deviations are discussed
and given an empirical fit. 相似文献
42.
43.
Cultures of Bacillus megaterium have been examined with laser-Raman spectroscopy in the 20–300 and 800–1800 cm?1 ranges. No lines were detected in the 20–300 cm?1 range, and evidence is presented that sporadic lines observed in the other range can be ascribed to experimental artifacts. 相似文献
44.
Let A be a nonempty finite subset of an additive abelian group G and let r and h be positive integers. The generalized h-fold sumset of A, denoted by \(h^{(r)}A\), is the set of all sums of h elements of A, where each element appears in a sum at most r times. The direct problem for \(h^{(r)}A\) is to find a lower bound for \(|h^{(r)}A|\) in terms of |A|. The inverse problem for \(h^{(r)}A\) is to determine the structure of the finite set A for which \(|h^{(r)}A|\) is minimal with respect to some fixed value of |A|. If \(G = \mathbb {Z}\), the direct and inverse problems are well studied. In case of \(G = \mathbb {Z}/p\mathbb {Z}\), p a prime, the direct problem has been studied very recently by Monopoli (J. Number Theory, 157 (2015) 271–279). In this paper, we express the generalized sumset \(h^{(r)}A\) in terms of the regular and restricted sumsets. As an application of this result, we give a new proof of the theorem of Monopoli and as the second application, we present new proofs of direct and inverse theorems for the case \(G = \mathbb {Z}\). 相似文献
45.
In the manganite La1‐xMxMnO3 (M = Ca, Ba, Sr) the doping concentration introduces a mixed valency (Mn3+, Mn4+) which governs the magnetic and electrical properties of the compound. The perovskite oxides La1‐3xCaxBaxSrxMnO3 (x = 0.00, 0.05, 0.10) were prepared by chemical method. Single‐phase formation is confirmed by XRD studies. The electrical behavior of compositions with x = 0.00, 0.05 and 0.10 in the system La1‐3xCaxBaxSrxMnO3 was studied in the temperature range 300‐420 K. It is observed that conductivity decreases with increasing temperature as well as dopants concentration. Metallic behavior of these compositions decreases with increasing dopants concentration (x). The microstructures of these samples have been characterized using scanning electron microscopy (SEM). (© 2007 WILEY ‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
46.
Siwach OP Sen P 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,69(2):659-663
Ag nanoparticles in water phase have been synthesized employing the electro-exploding wire technique. A surface plasmon peak is observed at 400nm, characteristic of the Ag nanoparticles. A fluorescence emission peak is recorded at 300nm for excitation wavelengths in two different ranges 215-230 and 255-280nm. The position of the fluorescence peak remains fixed, irrespective of the excitation wavelength employed. These are assigned to electronic transition from different higher excited states to d levels of the Ag nanoparticles. In concomitant with these, there are two resonant absorptions at 5.76 and 4.59eV as evident from the fluorescence excitation spectra. 相似文献
47.
Structural organization of gold nanoparticles onto the ITO surface and its optical properties as a function of ensemble size 总被引:1,自引:0,他引:1
Khatri OP Murase K Sugimura H 《Langmuir : the ACS journal of surfaces and colloids》2008,24(8):3787-3793
Self-assembly of citrate-stabilized gold nanoparticles (AuNPs) onto an optically transparent indium tin oxide (ITO) surface followed by neutralization of these particles using dodecanethiol as a surfactant have been demonstrated. X-ray photoelectron spectroscopic (XPS) studies revealed the partial removal of citrate ions from the immobilized AuNPs, which advances the dilution of electrostatic attraction between AuNPs and the APS (amino-terminated monolayer)-functionalized ITO surface. The resultant AuNPs restore their mobility to some extent and form small ensembles. Some of the immobilized AuNPs were completely removed from the surface due to neutralization, as confirmed by XPS studies. Interparticle distance and size of ensembles were manipulated by consecutive cycles of immobilization and neutralization of AuNPs. Controlled nanostructural fabrication progression, which leads to two-dimensional lateral growth of AuNPs, provides a method for systematically shifting the surface plasmon resonance band based on the increase in plasmon coupling among the closely placed AuNPs of an ensemble. The magnitude of shift increases with the size of ensemble. This manipulated chemical strategy offers a convenient and simple method to tune the optical properties of materials on a nanoscale. 相似文献
48.
Khatri OP Sano H Murase K Sugimura H 《Langmuir : the ACS journal of surfaces and colloids》2008,24(20):12077-12084
Photopatterning of a hexadecyl (HD) monolayer has been demonstrated using vacuum ultraviolet (VUV; lambda = 172 nm) light under controlled vacuum pressure with the objective of minimizing the pattern dimension. X-ray photoelectron spectroscopy (XPS) and lateral force microscopy (LFM) studies reveal that photodegradation of the HD monolayer not only is limited to the regions exposed to VUV but also spreads under the masked regions. The strong oxidants generated by VUV irradiation to atmospheric oxygen and water vapor diffuse toward the masked regions through the nanoscopic channels and photodissociate the monolayer under the masked area, near the photomask apertures, resulting in broadening of the photopattern. Such broadening decreases with decreased vacuum pressure inside the VUV chamber, associated with a decrease of oxidant concentration and reduction of their diffusion. Gold nanoparticles (AuNPs) were immobilized on the VUV patterned features to probe the dimension of the chemically active pattern. Field emission electron microscopy reveals the construction of 565 nm wide pattern features at a vacuum pressure of 10 Pa. This pattern widens to 1,030 nm at 10 (4) Pa using the same size apertures (500 nm) as printed on the photomask. This study provides insight for fabricating submicron patterns with high reproducibility and its exploitation for different applications, which includes the patterning of nanoparticles, biopolymers, and other nano-objects at submicron dimensions. 相似文献
49.
Parkash Chander 《International Journal of Game Theory》2007,35(4):539-556
This paper reinterprets the γ-core (Chander and Tulkens in Int Tax Pub Financ 2:279–293, 1995; in Int J Game Theory 26:379–401,
1997) and justifies it as well as its prediction that the efficient coalition structure is stable in terms of the coalition
formation theory. The problem of coalition formation is formulated as an infinitely repeated game in which the players must
choose whether to cooperate or not. It is shown that a certain equilibrium of this game corresponds to the γ-core assumption
that when a coalition forms the remaining players form singletons, and that the grand coalition is an equilibrium coalition
structure.
An earlier version of this paper was presented at the conference on Game Theory and Its Applications held in Mumbai in 2003
and was subsequently circulated as CORE Discussion Paper 2003/46. 相似文献
50.
Gao H Ye C Gupta OD Xiao JC Hiskey MA Twamley B Shreeve JM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(14):3853-3860
2,4,5-Trinitroimidazolate (TNI) salts with "high-nitrogen" cations tend to be highly hydrogen bonded and have heats of formation ranging up to 616 kJ mol(-1). Density, oxygen balance, and thermostability are enhanced by the presence of TNI. Based on theoretical calculations, all of the new salts are potential propellants. 相似文献