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991.
V.A. Grazhulis V.V. Kveder Yu.A. Osipyan Y.H. Lee R.L. Kleinhenz H. Van Camp C.P. Scholes J.W. Corbett 《Physics letters. A》1978,66(5):398-400
We present the first ENDOR measurements on dislocations in silicon, which measurements directly show the extended nature of the electron wave function on the dislocation. 相似文献
992.
The low temperature (125K) X-ray crystal structures of (TMTSF)2X, X=C104-, PF6-, and AsF6- reveal decreases in the intermolecular interand intrastack Se-Se contact distances upon cooling (298K to 125K) which are highly anisotropic and different from one salt to another. The changes in the interstack distances, which are normal to the stacking direction, are approximately twice those involving intrastack Se-Se interactions. These observations establish that the anisotropic structural changes which accompany decreased temperature are common to numerous (TMTSF)2X radical cation conducting salts. 相似文献
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996.
Lim SC Kim KS Lee IB Jeong SY Cho S Yoo JE Lee YH 《Micron (Oxford, England : 1993)》2005,36(5):471-476
We have installed two nanomanipulators, which can travel about 20mm with a minimum increment of 1 nm, for manipulation of nanostructured materials inside field-emission scanning electron microscope (FE-SEM). Both manipulators render motions in x, y, and z directions, providing various manipulation freedoms such as moving, bending, cutting, and biasing. In addition, we have conducted in situ characterization of the electrical breakdown of multi-walled carbon nanotubes (MWCNTs). Our results demonstrate the possibility that MWCNTs can be used as a gas sensor. 相似文献
997.
The recent rise of vancomycin-resistant enterococci (VRE) and vancomycin-resistant Staphylococcus aureus (VRSA) has given new impetus to the study of the binding between glycopeptide antibiotics and bacterial cell wall termini. Here, we report on an extensive first principles investigation of the binding of vancomycin, avoparcin, teicoplanin, and ristocetin aglycons with dipetides, Ac-d-Ala-X, where X = d-Lac and d-Ser (characteristic of VREs) and X = d-Ala, Gly (characteristic of non-VREs), and a model "methylated d-Ala" CH(2)CH(CH(3))COO(-), in liquid as well as gas phase. The gas-phase ordering of the binding, from strongest to weakest, is Gly, d-Ala, d-Ser, CH(2)CH(CH(3))COO(-), and d-Lac. Calculations show that the order of the Gly and d-Ala binding is reversed in solution. The results are in good agreement with recent experimental findings. 相似文献
998.
The methanol-catalyzed double-proton transfer of photoexcited 7-azaindole in the free cores of solvation-restricted reverse micelles takes place on the time scale of 90 ps, even shorter than in bulk methanol. This anomalous rate increase with a large kinetic isotope effect of 5 experimentally proves the widely discussed two-step model for the overall reaction of solvent-mediated proton transfer. On the other hand, the molecules in the bound layers and in the headgroup layers relax in 900 and 6000 ps, respectively, without going through proton transfer. The tautomerization and the relaxation of excited 7-azaindole can be exploited to probe the nanopools of methanol reverse micelles. 相似文献
999.
We study a zero range process on scale-free networks in order to investigate how network structure influences particle dynamics. The zero range process is defined with the rate p(n) = n(delta) at which particles hop out of nodes with n particles. We show analytically that a complete condensation occurs when delta < or = delta(c) triple bond 1/(gamma-1) where gamma is the degree distribution exponent of the underlying networks. In the complete condensation, those nodes whose degree is higher than a threshold are occupied by macroscopic numbers of particles, while the other nodes are occupied by negligible numbers of particles. We also show numerically that the relaxation time follows a power-law scaling tau approximately L(z) with the network size L and a dynamic exponent z in the condensed phase. 相似文献
1000.
Hinson JW Huang GS Lee J Miller DH Pavlunin V Rangarajan R Sanghi B Shibata EI Shipsey IP Cronin-Hennessy D Park CS Park W Thayer JB Thorndike EH Coan TE Gao YS Liu F Stroynowski R Artuso M Boulahouache C Blusk S Dambasuren E Dorjkhaidav O Mountain R Muramatsu H Nandakumar R Skwarnicki T Stone S Wang JC Csorna SE Danko I Bonvicini G Cinabro D Dubrovin M McGee S Bornheim A Lipeles E Pappas SP Shapiro A Sun WM Weinstein AJ Briere RA Chen GP Ferguson T Tatishvili G Vogel H Watkins ME Adam NE 《Physical review letters》2005,94(19):191801
Using the CLEO detector at the Cornell Electron Storage Ring, we have studied the distribution of kinematic variables in the decay lambda(+)(c)lambda--> e(+)nu(e). By performing a four-dimensional maximum likelihood fit, we determine the form factor ratio, R= f(2)/f(1) = -0.31 +/- 0.05(stat) +/- 0.04(syst), the pole mass, M(pole) = [2.21 +/- 0.08(stat) +/- 0.14(syst)] GeV/c(2), and the decay asymmetry parameter of the lambda(+)(c), alpha (lambda(c)) = -0.86 +/-0.03(stat) +/- 0.02(syst), for q(2) = 0.67 (GeV/c(2))(2). We compare the angular distributions of the lambda(+)(c) and lambda(-)(c) and find no evidence for CP violation: A(lambda(c)) = (alpha(lambda(c)) + alpha (lambda(c)))/(alpha(lambda(c))-alpha(lambda(c))) = 0.00 +/- 0.03(stat) +/- 0.01(syst) +/- 0.02, where the third error is from the uncertainty in the world average of the CP-violating parameter, A(lambda), for ppi(-). 相似文献