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71.
72.
JOHN ORLANDO 《珠算》2011,(7):72-75
面对预算,作为财务总监的你,是兴奋、乐观、干劲十足,还是头疼、无奈、缺乏信心?根据Centage公司和管理及行政学院(IOMA)的调查,最糟糕的是由于不完善的预算编制进程造成的预算不准确,从而明显降低相关各方对预算的信心。 相似文献
73.
CHRIS LAMBERT ROY S. SINCLAIR T. GEORGE TRUSCOTT EDWARD J. LAND MILES R. CHEDEKEL CHUNG-TSING LIU† 《Photochemistry and photobiology》1984,39(1):5-10
Abstract— The photochemistry of several 4-hydroxy- and 4-methoxybenzothiazoles has been investigated by laser flash photolysis. In aqueous solutions of pH3–12, the 4-hydroxybenzothiazole chromophore undergoes monophotonic photoionization to afford e- aq with quantum yields on the order of 0.06; no evidence for triplet species was obtained. The spectra and stability of the resultant free radicals were determined using pulse radiolysis. In contrast, triplet transients with life-times on the order of 8 mUs are readily observable upon irradiation of the 4-methoxybenzothiazole analog. Triplet sensitization experiments with the water-soluble carotenoid crocetin were employed to obtain the triplet extinction coefficients and subsequently the triplet quantum yields. The significance of these differences in photochemical behavior is discussed in relationship to the photochemistry and photobiology of the epidermal melanin pigment pheomelanin. 相似文献
74.
OVERSTREET GEORGE A. JR; BREDLEY EDWIN L. JR 《IMA Journal of Management Mathematics》1996,7(4):291-311
Although credit-scoring models represent a widely used managerialaid for large financial intermediaries, the vast majority ofU.S. credit unionsrelatively small cooperatively ownedretail intermediaries, constrained by sample and funding limitationshaveyet to adopt such techniques. Lovie & Lovie (1986) havetheorized that the flat-maximum effect or curve of insensitivityassociated with linear scoring models could be advantageousin areas of applied prediction such as credit scoring. In thiscontext, we reported the relative predictive power of genericcredit-scoring models versus customized models in an earlierpaper (Overstreet et al. 1992). Unfortunately, these findingswere not readily adaptable to the credit-union industry dueto a dated sample with incomplete credit-bureau information.Consequently, from 1988 to 1991, we gathered a refined databasefrom which to further develop and field-test generic scoringmodels in the credit-union environment. The results reportedherein not only confirm, but amplify, the relative predictivepower of such models found earlier. Relative costs and benefitsof generic versus customized models are modelled for a representativecredit union. Future research directions are set forth in theconclusions. 相似文献
75.
76.
DE-CHAO WANG FOO-TIM CHAU EDMOND P. F. LEE ALEXANDER KAI-MAN LEUNG JOHN M. DYKE 《Molecular physics》2013,111(6):995-1005
Geometry optimization and harmonic vibrational frequency calculations at the CASSCF, MP2 and CCSD(T) levels with basis sets up to 6-311G(2df) quality were carried out on the X1Σ+states of FCN and ClCN and the X2Π and A2Σ+ states of their cations. Adiabatic ionization energies were calculated up to the CCSD(T)/6-311G(3df)//CCSD(T)/6-311G(2d) level. Some B3LYP calculations were performed also for the ground states of the neutral molecules and the cations. Franck-Condon simulations were performed for the first two bands in the He I photoelectron spectra of FCN and ClCN by employing the ab initio computed geometries and frequencies. By comparing the observed and the simulated spectra obtained from different CN and CX (X = F or Cl) ionic bond lengths chosen on the basis of the ab initio computed values, the following structural parameters are obtained for the two lowest-lying states of FCN+ and ClCN+ (the method of deriving the uncertainties is described): 相似文献
77.
We present a methodology for the efficient calculation of the shock Hugoniot using standard molecular simulation techniques. The method is an extension of an equation of state methodology proposed by Erpenbeck [1992, Phys. Rev. A, 46, 6406] and is considered as an alternative to other methods that generate Hugoniot properties. We illustrate the methodology for shocked liquid N2 using two different simulation methods: (a) the reactive Monte Carlo method for a reactive system; and (b) the molecular dynamics method for a non-reactive system. The method is shown to be accurate, stable and generally independent of the algorithm parameters. We find excellent agreement with results calculated by other previous simulation studies. The results show that the methodology provides a simulation tool capable of determining points on the shock Hugoniot from a single simulation in an efficient, straightforward manner. Further applications and extensions of the method are briefly discussed. 相似文献
78.
JOHN M. BROWN 《Molecular physics》2013,111(23-24):3419-3426
An additional term in the effective Hamiltonian for a molecule in a 2S+1Π state subject to a small Renner—Teller effect is derived. It takes the form of a rotational dependence of the Renner—Teller operator and is assigned the parameter ?ω2,D . This term reproduces two characteristics of the spin—rotational levels of Renner—Teller molecules, both of which are well documented by experimental examples but are not explicable in terms of the previous effective Hamiltonian. These are the small difference between the B values of different vibronic components of the same bending vibrational level and the anomalously strong dependence of the spin—rotation parameter γ on ν2 for molecules with S > 0. These effects have been explained by previous workers using perturbation theory but in a less general and more complicated fashion. 相似文献
79.
ADRIAN J. CARMICHAEL CHRISTOPHER HARDACRE JOHN D. HOLBREY MARK NIEUWENHUYZEN KENNETH R. SEDDON 《Molecular physics》2013,111(10):795-800
X-ray reflectivity measurements in air of thin films of 1-alkyl-3-methylimidazolium salts in the liquid, liquid crystalline and solid states supported on Si(111) are described. The films show Bragg features in both liquid crystalline and solid phases, but only after an initial annealing cycle. Kiessig fringes are observed only for the 1-octadecyl-3-methyl-imidazolium hexafluorophosphate films and, following analysis using Parratt32, a bi-layer model is proposed whereby the molecules are orientated with ionic groups at both salt-air and salt-silicon interfaces. 相似文献
80.
The frequency and temperature dependence of real (?′) and imaginary (?″) parts of the dielectric constant of polycrystalline complexes (α-CD)2 · LiI3 · I2 · 8H2O and (α-CD)2 · Cd0.5 · I5 · 26H2O (α-CD = α-cyclodextrin) has been investigated over the frequency and temperature ranges of 0–100 kHz and 12–300 K. The dielectric behaviour is described well by Debye type relaxation (α-dispersion). Both systems exhibit an additional Ω dispersion at low frequencies which is attributed to ionic conductance and is much greater in the case of Li due to the greater mobility of cations Li+. The temperature dependence of ?′ reveals the existence of two kinds of water molecule in the case of the (α-CD)2 · Cd0.5 · I5 · 26H2O complex; these can be classified as tiqhtly bound and easily movable water molecules that cause two steps in ?′ versus T plots. In the case of the (α-CD)2 · LiI3 · I2 · 8H2O complex the water molecules are tightly bound and as a result only one step is observed in these graphs. These finding are also confirmed from the ?″max versus T plots, which exhibit the same number of steps with ?′, and from calorimetric measurements. The order-disorder transition or the transformation of normal hydrogen bonds to flip-flop type has been observed as a peak in ?″ versus T plots that is more intense and narrow in the case of Li and less high but more broad in Cd. The relaxation time vanes in a α-like curve (from 120 K to 240 K) and rises rapidly for temperatures greater than 240 K, indicating the existence of a new process involving the breaking of hydrogen bonds (normal or flip-flop type). The calculated values of activation energy (0.35–0.62 kBTtrans) reveal the greater stability of the Li compared with the Cd complex. The starting value of 8.2–8.4 μs for τ is the same as observed in β-CD complexes with guest 4-t-butylbenzyl alcohol (TERB). However, the activation energies of these are greater (1.1–1.7kBTtrans), indicating greater stability for β-CD complexes. 相似文献