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1.
The centrosymmetric title compound, [Cd2{CH3OC6H4P(OC5H9)S2}4], features an eight‐membered [? Cd? S? P? S? ]2 ring owing to the presence of bridging dithiolate ligands. Tetrahedral coordination geometries for cadmium are completed by chelating ligands. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
2.
In this study, nano hydroxyapatite doped with yttrium (2.5, 5, and 7.5 mol%) and fluoride (2.5 mol%) ions were synthesized by precipitation method and sintered at 900°C, 1100°C, and 1300°C. Raman spectroscopy was applied to track the structural modifications in pure and doped hydroxyapatites. The results showed that the main characteristic band of pure hydroxyapatite at 963 cm?1 was not affected significantly by ion doping but exhibited higher intensity with increasing sintering temperature. Due to fluoride substitution, the 1048 and 1034 cm?1 bands of pure hydroxyapatites appeared with a wavenumber shift in the spectra of ion-doped hydroxyapatites. The 333 cm?1 band of pure hydroxyapatite disappeared and an additional calcium–fluor bond at 322 cm?1 was observable in ion-doped hydroxyapatites. Two fluorescence bands at 770 and 697 cm?1, which were also observed in the spectra of pure hydroxyapatites, shifted to higher wavenumbers in the spectra of ion-doped hydroxyapatites. This was considered to result from the perturbation in the hexagonal structure of hydroxyapatite due to yttrium and fluoride codoping.  相似文献   
3.
We employ QCD sum rules to calculate the coupling constant g by studying the three point -correlation function. Our result complements the analysis of this coupling constant utilizing the experimental value of the 00 decay rate studied within the framework of chiral perturbation theory including vector meson and meson intermediate states.  相似文献   
4.
The general analysis of the rare Bc→Ds *+- decay is presented by using the most general, model independent effective Hamiltonian. The dependencies of the branching ratios and of the longitudinal, normal and transversal polarization asymmetries for ℓ- and the combined asymmetries for ℓ- and ℓ+ on the new Wilson coefficients are investigated. Our analysis shows that the lepton polarization asymmetries are very sensitive to the scalar and tensor type interactions, which will be very useful in looking for new physics beyond the standard model.  相似文献   
5.
OBJECTIVE: The aim of this study was to identify the effects of objective laryngopharyngeal reflux (LPR) on the acoustic parameters of patients by comparing their voice samples with that of control subjects. STUDY DESIGN: Prospective study in two tertiary reference hospitals. METHODS: 48 consecutive patients with symptoms related to LPR and 64 control subjects were included in the study. Suspected LPR patients underwent a 24-hour ambulatory pH monitoring, and 25 (52%) of them were shown to have objective LPR. Acoustical evaluation results of objective LPR patients were compared with that of symptomatic LPR patients and control subjects. RESULTS: All frequency perturbation values obtained from objective and symptomatic LPR patients were higher than the control subjects (P<0.01). Mean fundamental frequency, amplitude perturbation measures, and noise-to-harmonics ratio were not significantly different between groups. CONCLUSION: LPR patients have significantly different frequency perturbation values than control subjects.  相似文献   
6.
In this paper, a new algorithm to solve a general 0–1 programming problem with linear objective function is developed. Computational experiences are carried out on problems where the constraints are inequalities on polynomials. The solution of the original problem is equivalent with the solution of a sequence of set packing problems with special constraint sets. The solution of these set packing problems is equivalent with the ordering of the binary vectors according to their objective function value. An algorithm is developed to generate this order in a dynamic way. The main tool of the algorithm is a tree which represents the desired order of the generated binary vectors. The method can be applied to the multi-knapsack type nonlinear 0–1 programming problem. Large problems of this type up to 500 variables have been solved.  相似文献   
7.
Non-zero dispersion fiber (NZDF) ribbon cable has recently become a considerable alternative in long-haul high-speed network construction. Since long-distance high-bit rate transmission requires low polarization mode dispersion (PMD), it is very important to know the PMD performance of this type of optical fiber cables. In this paper, we report experimental analysis of effects of the cable design and environmental parameters, in particular ribbon thickness, positions of fibers in the ribbon, flexing and vibration, on PMD performances of several slotted-core fiber ribbon cables. Results show that ribbon thickness and positions of fibers in the ribbon alter the PMD values of NZDF ribbon cables. Also, 23% and 11% PMD variations have been determined in flexing and vibration experiments, respectively. Moreover, it has been observed that vibration amplitude has significant effects and vibration frequency has little effects (14% and 6% variations, respectively) on fiber PMD. Results are important for understanding effects of installation conditions and wind, especially for aerial fibers, on PMD values of cables.  相似文献   
8.
Spin-spin relaxation timeT 2 values of serum with and without iron were measured by magnetic resonance imaging (MRI) to find the proton relaxivity of Fe(III) in serum.T 2 values in serum containing definite amounts of added iron were also measured before and after addition of ascorbic acid. The difference in the 1/T 2 of serum with and without ascorbic acid was used for recalculation of the added iron values. Recalculated iron values confirm that the difference in healthy serum is caused by iron only. In addition, in order to find the paramagnetic contribution of serum iron,T 2 values of iron-deficient, healthy and iron-overloaded serum were measured before and after addition of ascorbic acid. The difference in the 1/T 2 values was then applied to the calculation of the serum iron values. The consistency of iron values determined from the difference to those by autoanalyzer suggests that the differences in diseased serum also represent the paramagnetic contribution of serum iron. The data imply that serum iron content in healthy, iron-deficient and iron-overloaded serum may be assessed by MRI.  相似文献   
9.
The European Physical Journal A - The ω-meson photoproduction, γ + p→p + ω, is studied in the framework of a model, containing π-meson exchange in t-channel and...  相似文献   
10.
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