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1.
Ruihua Li Zhanpeng Jiang Yuntao Guan Hongwei Yang Bo Liu 《Journal of Raman spectroscopy : JRS》2009,40(9):1200-1204
Raman spectra in the O H stretching region of aqueous salt solutions were measured and compared, and the effects of metal ions on water structure deduced. The effects of alkali ions, alkaline ions or the first‐row transition metals on water structure were found to be similar. Differences of metal ionic effects on water structure exist among Na+, Mg2+ and Al3+, and between Ca2+ and Mn2+ and Al3+ and Fe3+. The factors that influence the metal ionic effects on the water structure are the ionic charge, the outmost electronic structure and ionic size, the ionic charge being the most important. With a five‐component Gaussian deconvolution of the Raman spectra of the aqueous solutions of NaCl, MgCl2, AlCl3 and FeCl3 with concentrations of 0 to ∼1mol/l, the ionic effects were found to be similar on the bands at 3233, 3393, 3511 and 3628 cm−1, but different on the band at 3051 cm−1. With increasing polarization of the metal ion, the band at 3051 cm−1, due to strong hydrogen bonding, increases. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
2.
Sabater i Serra R Escobar Ivirico JL Meseguer Dueñas JM Andrio Balado A Gómez Ribelles JL Salmerón Sánchez M 《The European physical journal. E, Soft matter》2007,22(4):293-302
The dielectric relaxation spectrum of polycaprolactone (PCL) networks
hydrophilized with different amounts of 2-hydroxyethyl acrylate (HEA) is
investigated. PCL is a semicrystalline polyester with a complex relaxation
spectrum that includes the main α relaxation and two secondary modes
(β, γ) at lower temperatures. The overlapping of the
different relaxational modes was split by using several Havriliak-Negami
functions. Crosslinking the material modifies the dynamics of the main
relaxation process as reflected by the parameters that characterize the
Vogel behavior of the process and the dynamic fragility. The incorporation
of HEA units in the network results in a material with microphase
separation: two α processes are detected, the one corresponding to
the PCL chains and the new one associated to nanometric regions that contain
different amount of both comonomers. The incorporation of the HEA units in
the system involves the presence of a new βsw relaxation due to
the link of two side chains by water molecules through hydrogen bonding. 相似文献
3.
The self-consistent mode-coupling approximation of Colaiori and Moore [Phys. Rev. Lett. 86 (2001) 3946] is generalized to the analysis of the Sun–Guo–Grant equation to investigate its dynamic scaling properties in the strong-coupling regime. The corresponding values of the dynamic exponents are calculated for the substrate dimension d=1 and 2, respectively, and are also compared with previous analytical and numerical results. It can be seen that our discussion and calculation made in present paper are reasonable and reliable. 相似文献
4.
Structural-dynamic models of methyl-β-D-glucopyranoside have been constructed by a density functional method using a B3LYP
functional in bases 6-31G(d) and 6-31+G(d,p). Energies have been minimized. Structures, dipole moments, polarizabilities,
frequencies of normal modes in the harmonic approximation, and the intensity distribution in the molecular IR spectrum have
been calculated. The calculation results have been compared with both the experimental spectra of methyl-β-D-glucopyranoside
in the region 400–3700 cm–1 and data obtained within the framework of an approach that uses the classical valence-force method to calculate normal mode
frequencies and the quantum-chemical CNDO/2 technique to calculate the electronic structure. 相似文献
5.
6.
The low-energy structures and the electronic and the
magnetic properties of small NiNiNi$_{m}$Ti$_{n}$ clusters, lowest-energy structure,
electronic and magnetic properties Project supported by the National
Natural Science Foundation of China (Grant No.~10874039), and the
Natural Science Foundation of Hebei Province of China (Grant
Nos.~A2009000246 and 2009000243). 3120A, 3640B, 2110K 7/3/2009 12:00:00 AM The low-energy structures and the electronic and the
magnetic properties of small NiNiNi$_{m}$Ti$_{n}$ clusters, lowest-energy structure,
electronic and magnetic properties Project supported by the National
Natural Science Foundation of China (Grant No.~10874039), and the
Natural Science Foundation of Hebei Province of China (Grant
Nos.~A2009000246 and 2009000243). 3120A, 3640B, 2110K 7/3/2009 12:00:00 AM The low-energy structures and the electronic and the
magnetic properties of small Ni$_{n}$Ti$_{n}$ ($n=1$--$6$) and
Ni$_{m}$Ti$_{n}$ ($1 \le n \le 4$, $1 \le m \le 4$, $n \ne m$)
clusters are investigated by performing all-electron calculations
based on density functional theory. Ground states and several
isomers near the ground states are determined for these clusters.
The results indicate that the growth of small Ni$_{m}$Ti$_{n}$
clusters prefers to form rich Ti--Ni and Ti--Ti bonds. When the
percentage of titanium atoms is significantly greater than that of
nickel atoms, the nickel atoms are most frequently found above
the surface; in contrast, the titanium atoms prefer the bridging
sites. A M\"{u}lliken spin population analysis indicates that the
total spin of titanium-nickel clusters is not always zero. http://cpb.iphy.ac.cn/CN/10.1088/1674-1056/19/4/043102 https://cpb.iphy.ac.cn/CN/article/downloadArticleFile.do?attachType=PDF&id=111644 NimTin;clusters;lowest-energy;structure;electronic;and;magnetic;properties The low-energy structures and the electronic and the magnetic properties of small Nin Tin(n = 1-6) and Ni m Ti n(1 ≤ n ≤ 4,1 ≤ m ≤ 4,n ≠ m) clusters are investigated by performing all-electron calculations based on density functional theory.Ground states and several isomers near the ground states are determined for these clusters.The results indicate that the growth of small Ni m Ti n clusters prefers to form rich Ti-Ni and Ti-Ti bonds.When the percentage of titanium atoms is significantly greater than that of nickel atoms,the nickel atoms are most frequently found above the surface;in contrast,the titanium atoms prefer the bridging sites.A Mu¨lliken spin population analysis indicates that the total spin of titanium-nickel clusters is not always zero. 相似文献
7.
There is a type of nodal surface imposed by symmetry on wavefunctions.These surfaces are crucial to the ordering of low-lying states.Based on an analysis of this type of surface and based on existing theoretical results,the feature of the low-lying spectrum of the He-tetramer is studied,and the candidates of bound states and narrow resonances are suggested. 相似文献
8.
YUSUF PANDIR 《Pramana》2014,82(6):949-964
In this paper, new exact solutions, including soliton, rational and elliptic integral function solutions, for the generalized Zakharov–Kuznetsov modified equal-width equation are obtained using a new approach called the extended trial equation method. In this discussion, a new version of the trial equation method for the generalized nonlinear partial differential equations is offered. 相似文献
9.
Mössbauer spectra of polycrystalline samples of Fe(Ox)3, Fe(BPHA)3 and K3[Fe(malonate)3] · 3H2O exhibit fast relaxation patterns in the temperature range 4.2–300 K. The magnetic hyperfine splitting has nearly completely collapsed due to rapid electronic spin-spin relaxation of the Fe ions. We use a static Hamiltonian
and describe the spin-spin interaction by an effective field Hamiltonian
. From this the relaxation supermatrix and the Mössbauer spectra are calculated. The random texture of the samples is taken into account by averaging the radiation dipole operators over the whole sphere. Least-squares fits of the spectra for longitudinal, isotropic and transverse spin relaxation are presented. From the fits the temperature dependence of the relaxation is obtained. We conclude that in these materials the iron is present as high-spin Fe(III) and that the crystal field splitting constantD is greater than zero. The sign ofV
zz
is found to be positive. 相似文献
10.
Xuewen Wan William J. Kossler Carey E. Stronach David R. Noakes 《Hyperfine Interactions》1999,122(3-4):233-237
Zero‐field muon spin relaxation (ZF‐μSR) data for dilute spin magnetic systems have been widely interpreted with what is called
a Kubo–Toyabe form based on a Lorentzian distribution of local field components. We derive here the proper magnetic field
magnitude distribution using independent and uncorrelated component distributions. Our result is then compared to the previously
accepted formula for ZF‐μSR. We discuss the origins of the magnetic field component and magnitude distributions. Further,
we found that after rescaling the magnetic field, the differences that are amenable to experimental examination are quite
small, although the interpretations behind them are quite different.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
11.
12.
The measurements of the rotational spectrum of 1,4-dioxane-water complex, performed by pulsed jet Fourier transform microwave spectroscopy, have been extended to the 7–18.5 GHz frequency region and to two additional isotopologues, 1,4-dioxane···H2 17O and 1,4-dioxane···HOD. The effective orientation of water in the complex has been obtained from the 17O quadrupole coupling constants. 相似文献
13.
Z. Liu D. SeweryniakP.J. Woods C.N. DavidsM.P. Carpenter T. DavinsonR.V.F. Janssens R.D. PageA.P. Robinson J. ShergurS. Sinha X.D. TangF.R. Xu S. Zhu 《Physics letters. [Part B]》2011,702(1):24-27
Proton radioactivity from 117La was re-investigated with much improved statistics and precision. Only the ground-state proton decay (Ep=813(3) keV, T1/2=20.1(25) ms) was observed, no evidence for a previously reported isomeric proton decay was found. Prompt γ rays in 117La were identified using the Recoil-Decay Tagging method. Overall the data indicate that the proton-emitting state is associated with a Kπ=3/2+ configuration, in agreement with all the published proton-decay calculations and predictions for the ground-state configuration of 117La calculated in the framework of either adiabatic or non-adiabatic particle models. However, this is not in agreement with the most recent state-of-the-art quasi-particle non-adiabatic model calculations which predict a Kπ=7/2− configuration. 相似文献
14.
The IR spectrum and structure of methyl-β-D-glucopyranoside have been studied theoretically taking into account the influence
on them of the hydrogen bond formed in the sample. Density-functional theory with the B3LYP functional in basis 6-31G(d) was used to minimize the energies and calculate the structures, electro-optical parameters, force constants, frequencies
of normal harmonic vibrations, and intensities in IR spectra of the simplest H-bonded dimeric complexes of methyl-β-D-glucopyranoside.
The calculated spectra of H-bonded complexes were compared with those of the free molecule and the experimental spectrum in
the range 400–3700 cm–1. Conclusions about the structure of methyl-β-D-glucopyranoside were made. The interpretation of its IR spectrum was refined. 相似文献
15.
Spectral densities of motion were determined by deuteron NMR relaxation measurements in the ‘ordered’ smectic-B and -G phases of 4-n-pentyloxybenzylidene-d 1-4′-heptylaniline and 4-n-pentyloxybenzylidene-4′-heptylaniline-2,3,5,6-d 4 at two different Larmor frequencies. Different forms of motional behaviour are involved in these phases in comparison with those in the high temperature ‘disordered’ phases. Specifically, internal ring rotation and direction fluctuation are not effective in the ordered smectic phases. In addition, the fast rotation of the molecule about its long molecular axis is now strongly hindered to give a libration motion of angular amplitudes of about 100°. The third-rate model is again used to describe the molecular reorientation, taking the restricted γ motion into account. The effects of phase biaxiality on spin relaxation in the smectic-G phase are also discussed. 相似文献
16.
17.
《Physics letters. [Part B]》1988,213(2):195-202
We have studied the eigenvalues of the Wilson fermion matrix on various lattice sizes and for a range of coupling constants, β, in the quenched approximation. The implications for the phase structure of lattice QCD in the presence of Wilson fermions are discussed. 相似文献
18.
《声学学报:英文版》1991,(3)
The directionality of the sound generated by laser-induced liq-uid breakdown in water is investigated both theoretically and experimen-tally.The theoretical analysis is based on the following model.A seriesof small spherical cavities including plasma are homogeneously distributedon a short straight line segment and every such cavity may be consideredas a point source radiating acoustic impulse.Theoretical expressions ofthe relations between the amplitude and width of acoustic impulse and thereceiving direction are given.Experimental results are in agreement withtheoretical predictions. 相似文献
19.
F. Bernardi M. Behar J.H.R. dos Santos F. Dyment 《Applied Physics A: Materials Science & Processing》2005,80(1):69-72
The diffusion of Al in -Hf was studied in the 973–1298 K temperature range by using the nuclear resonance technique. The measurements show that the diffusion coefficient follows an Arrhenius behavior D(T)=D0exp(-Q/RT), where D0=(3±2)×10-4 m2s-l and Q=337±10 kJ/mol. The activation energy is typical of a substitutional mechanism of diffusion, as can be deduced from self-diffusion measurements. On the other hand, differences between the present and previous published results can be attributed to the different purity of the samples used in each experiment. PACS 66.30.-h; 66.30.Jt 相似文献
20.
Determination of the anion O-3 geometry by Franck-Condon simulations of its photoelectron spectrum 总被引:1,自引:1,他引:1
A theoretical method to calculate multidimensional Franck-Condon factors including Duschinsky effects is described and used to simulate the photoelectron spectroscopy of the anion O-3. Geometry optimization and harmonic vibrational frequency calculations have been performed on the (X~)1A1 state of O3 and (X~)2B1 state of O-3. Franck-Condon analyses and spectral simulation were carried out on the first photoelectron band of O-3. The theoretical spectrum obtained by employing CCSD(T)/6-311+G(2d,p) values are in excellent agreement with the observed one. In addition, the equilibrium geometry parameters, re(OO)= 0.135 5±0.000 5 nm and θe(O-O-O) =114.5±0.5°, of the (X~)2B1 state of O-3, are derived by employing an iterative Franck-Condon analysis procedure in the spectral simulation. 相似文献