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1.
The laser-induced fluorescence excitation spectrum of CoC was recorded in the spectral region from 13500 cm-1 to 22000 cm-1, in which the CoC molecules were produced by the reaction of sputtered cobalt atoms with methanol under supersonic jet cooled conditions. Much of the visible spectrum was assigned to transitions between the X2∑+ ground state and F2∑+ state. The 11 bands assigned as (v’=3-13, 0) transitions of the F2∑+- X2∑+ band system were observed and rotationally analyzed. Equilibrium constants for the F2∑+ state were Te=1362 cm-1, ωe=669 cm-1 ,ωe?e=4.3 cm-1, Be=0.546 cm-1, and Re=1.758A. Some new bands were observed. 相似文献
2.
A. El Abd 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(2):321-326
The thermal neutron cross-sections and resonance integrals of the 186W (n,γ) 187W and 98Mo (n,γ) 99Mo reactions in the thermal and 1/E regions, respectively, of a thermal reactor neutron spectrum have been experimentally determined by the activation method
using 197Au (n,γ) 198Au reaction as a single comparator. The high purity natural W, Mo, and Zr foils; and Au wire diluted in aluminum, were irradiated
without Cd shield in two neutron irradiation sites, characterized with different values for the thermal-to-epithermal flux
ratios, f at the Second Egyptian Research Reactor (ETRR-2). The induced activities in the samples were measured by high-resolution
γ-ray spectrometry with a calibrated germanium detector. Thermal neutron cross-sections for 2200 m/s neutrons and resonance
integrals for the 186W (n,γ) 187W and 98Mo (n,γ) 99Mo reactions have been obtained relative to the reference values, σ0 = 98.65 ± 0.09 b and I
0 = 1500 ± 28 b for the 197Au (n,γ) 198Au reaction. The necessary correction factors for thermal neutron and resonance neutron self-shielding effects, and the epithermal
flux index (α) were taken into account in the determinations. The results obtained were: σ0 = 38.43 ± 0.4 b and I
0 = 502 ± 65 b for 186W (n,γ) 187W, and σ0 = 0.137 ± 0.014 band I
0 = 6.47 ± 0.8 for 98Mo (n,γ) 99Mo. These results are discussed and compared with previous measurements and evaluated data in literature. The traditional
method of determining thermal cross-sections and resonance integrals via neutron irradiation with and without Cd shield in
one irradiation position was avoided in this work by neutron irradiation without Cd shield in at least two different neutron
irradiation positions. This method provides alternative way for determining thermal cross-sections and resonance integrals
simultaneously. 相似文献
3.
Emese Szabó Jérémy Tarmoul Alexandre Tomas Christa Fittschen Sándor Dóbé Patrice Coddeville 《Reaction Kinetics and Catalysis Letters》2009,96(2):299-309
Kinetics of the •OH-initiated reactions of acetic acid and its deuterated isomers have been investigated performing simulation chamber experiments
at T = 300 ± 2 K. The following rate constant values have been obtained (± 1σ, in cm3 molecule−1 s−1): k
1(CH3C(O)OH + •OH) = (6.3 ± 0.9) × 10−13, k
2(CH3C(O)OD + •OH) = (1.5 ± 0.3) × 10−13, k
3(CD3C(O)OH + •OH) = (6.3 ± 0.9) × 10−13, and k
4(CD3C(O)OD + •OH) = (0.90 ± 0.1) × 10−13. This study presents the first data on k
2(CH3C(O)OD + •OH). Glyoxylic acid has been detected among the products confirming the fate of the •CH2C(O)OH radical as suggested by recent theoretical studies. 相似文献
4.
The absorption spectrum of N2+ has been studied using optical-heterodyne velocity mod-ulation spectroscopy in the near-infrared region. The observed spectral lines were assigned to the (3,1), (4,2), (5,3), (8,5) bands of the A2Πu-X2Σ+g system and the line lists were provided. The (5,3) band was studied for the first time. Fourteen rotational-resolved bands in literatures were fitted together with our observed bands and the molecular constants were obtained for υA=0-9 and υX=0-5. 相似文献
5.
Ohne Zusammenfassung 相似文献
6.
V. V. Sharutin V. S. Senchurin O. K. Sharutina N. V. Somov A. V. Gushchin 《Russian Journal of Coordination Chemistry》2011,37(11):854-860
The complexes [Bu4N]2+[PtBr6]2− (I), [Ph4P]2+[PtBr6]2− (II), and [Ph3(n-Am)P]2+ (III) are synthesized by the reactions of tetrabutylammonium bromide, tetraphenylphosphonium bromide, and triphenyl(n-amyl)-tetraphenylphosphonium bromide, respectively, with potassium hexabromoplatinate (mole ratio 2: 1). After recrystallization
from dimethyl sulfoxide, complexes I, II, and III transform into [Bu4N]+[PtBr5(DMSO)]− (IV), [Ph4P]+[PtBr5(DMSO)]− (V), and [Ph3(n-Am)P]+[PtBr5(DMSO)]− (VI). According to the X-ray diffraction data, the cations of complexes IV–VI have a slightly distorted tetrahedral structure. The N-C and P-C bond lengths are 1.492(7)–1.533(6) and 1.782(10)–1.805(10)
?, respectively. The platinum atoms in the mononuclear anions are hexacoordinated. The dimethyl sulfoxide ligands are coordinated
with the Pt atom through the sulfur atom (Pt-S 2.3280(18)–2.3389(11) ?). The Pt-Br bond lengths are 2.4330(6)–2.4724(6) ?. 相似文献
7.
Transitions of the 6υ3 overtone band of 14N2 16O near 775 nm have been studied by continuous-wave cavity ring-down spectroscopy. Line positions and intensities were derived from a fit of the line shape using a hard-collisional profile. The line positions determined with absolute accuracy of 5×10-4 cm-1 allowed us to reveal finer ro-vibrational couplings taking place after J>14 except a strong anharmonic interaction identified by the effective Hamiltonian model. The absolute line intensities have also been retrieved with an estimated accuracy of 2% for a majority of the unblended lines. A new set of ro-vibrational and dipole moment parameters were derived from the experimental values. A comparison between the line positions and intensities of the 6υ3 band obtained in this work and those from previous studies is given. 相似文献
8.
O. G. Shakirova M. Grunert D. Yu. Naumov F. Gütlich L. G. Lavrenova 《Journal of Structural Chemistry》2010,51(1):45-52
Synthesis procedures for mix-ligand complexes with a composition of Fe(Htrz)3(1-x)(NH2trz)3x
SiF6 · mH2O, 0 ≤ x ≤ 1, m=1,2 are developed. Solid phases are isolated from water-ethanol solutions and studied by X-ray phase analysis, the method
of static magnetic susceptibility (temperature range of 100 K to 400 K), IR and M?ssbauer spectroscopy (at 200 K and 298 K).
The temperatures of direct and inverse transitions are shown to depend on the complex composition. 相似文献
9.
M. A. Ryazanov B. N. Dudkin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(13):2318-2321
The distribution of the acid-base centers on the surface of α-Al2O3 suspension particles was studied by potentiometric titration, and the corresponding pK spectra were constructed. It was inferred that the double electric layer created by the supporting electrolyte substantially
affected the screening of the acid-base centers on the particle surface of the suspension. 相似文献
10.
YouQian Ding HongQing Sun ZhiHong Yang XiaoHu Liang XiaoRong Wang ShengDong Zhang AnZhi Cui 《中国科学B辑(英文版)》2009,52(5):690-692
The influence of mechanic motion on the decay rate of 32P was studied by means of liquid scintillation counting (LSC). The results indicate that, on the Northern Hemisphere, the
half life of 32P in anticlockwise circular centrifuge rotation (radius 10 cm, 4000 r/min) equals the one in natural conditions within 0.6
percent uncertainty. 相似文献
11.
V. A. Maksakov N. V. Pervukhina N. V. Podberezskaya M. Yu. Afonin V. A. Potemkin V. P. Kirin 《Journal of Structural Chemistry》2008,49(5):894-900
The crystal structure of the Os3(μ,η2-O=CC6H5)(η3-C3H5)(CO)9 cluster synthesized by the reaction of the (μ-H)Os3(μ-O=CC6H5)(CO)10 complex with allylamine in chloroform was determined by X-ray analysis. Prolonged storage of the reaction mixture led to
N-C bond cleavage in allylamine and η3-addition of the allyl fragment at one of the Os atoms (Os-C 2.246 ?, 2.248 ?, and 2.273 ?). The unit cell parameters of the
complex are a = 9.494(1) ?, b = 10.479(1) ?, c = 12.474(2) ?, α = 84.55(1)°, β = 70.08(1)°, γ = 70.72(1)°, V = 1255.8(4), ?3, space group P
, Z = 2; C19H10O10Os3; d
calc = 2.922 g/cm3, 3085 I
hkl
> 2σ
I
of 3611 collected reflections; R = 0.0252. The structure of Os3(μ,η2-O=CC6H5)(η3-C3H5)(CO)9 is molecular. The plane of the Os3 triangle and the OsCOOs plane are connected according to the “butterfly” principle with an angle of 103.4° between them.
The Os-Os distances in the cluster core vary from 2.836(1) ? to 2.844(1) ?; the Os-Ccarb distances are 1.88(1)–1.97(1) ?; the distances to the atoms of the bridging ligands are Os-C 2.11(1) ?, Os-O 2.14(1) ?; the
O-C bridging bond is 1.24(1) ?. of the Os3(μ,η2-O=CC6H5)(η3-C3H5)(CO)9 triosmium cluster were studied theoretically. The potential curve of the internal rotation of the allyl ligand relative to
the Os(1)-C(9) bond was determined. The rotation barrier of the allyl ligand in crystal relative to the Os(1)-C(9) bond is
8.38 kJ/mol, and the rotation of the ligand is not hindered. The effects of the intra-and intermolecular interactions on the
conformation state of the cluster complex are considered.
Original Russian Text Copyright ? 2008 by V. A. Maksakov, N. V. Pervukhina, N. V. Podberezskaya, M. Yu. Afonin, V. A. Potemkin,
and V. P. Kirin
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 5, pp. 926–932, September–October, 2008. 相似文献
12.
13.
A. V. Sabylinskii S. P. Gabuda S. G. Kozlova D. N. Dybtsev V. P. Fedin 《Journal of Structural Chemistry》2009,50(3):421-428
Localization and molecular mobility of the ligands ([C8H4O4]2+ and [C6H12N2]0) of the host lattice and (CH3)2NCHO dimethyl formamide guest molecules in the inclusion compound [Zn2(C8H4O4)2(C6H12N2)]·n(H3C)2NCHO were studied on the basis of 1H NMR data. At room temperature, the longest axes of the dimethyl formamide guest molecules are ordered in parallel to the
C
4 symmetry axes, and the symmetry planes of these molecules are disordered, while preserving the tetragonal crystal system
of the inclusion compound. At lower temperatures, a phase transition takes place in view of the ordering in the guest sublattice.
Original Russian Text Copyright ? 2009 by A. V. Sabylinskii, S. P. Gabuda, S. G. Kozlova, D. N. Dybtsev, and V. P. Fedin
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 3, pp. 443–450, May–June, 2009. 相似文献
14.
D. A. Loginov A. A. Pronin Z. A. Starikova P. V. Petrovskii A. R. Kudinov 《Russian Journal of Coordination Chemistry》2010,36(11):795-800
Cobaltacarboranes (η1, η3-cyclooctenediyl)Co(Carb) (Carb = η-9-SMe2-7,8-C2B9H10, η-1-tBuHN-1,7,9-C3B8H10) were synthesized by the reaction of the carborane anions [Carb]− with the acetonitrile complex [(η1, η3-cyclooctenediyl)Co(MeCN)3]+ generated in situ upon the dissolution of [(η1, η3-cyclooctenediyl)Co(η-1,4-C6H4Me2)]+ in MeCN. The structures of (η1,η3-cyclooctenediyl)Co(η-9-SMe2-7,8-C2B9H10 and [(η2,η2-cyclooctadiene)Co((η-1,2,4,5-C6H2Me4)]BF4 were determined by X-ray diffraction analysis. 相似文献
15.
A strong deshielding effect is observed for the carbon signal of carbocation center (C+) in the 13C NMR spectra of coordinated propargyl cations [Cp2Mo2(CO)4(μ-η2,η3-(HC≡CCR1R2)]+ BF4− (R1 = R2 = H) 1, (R1 = Me, R2 = H) 2, and (R1 = R2 = Me) 3 when hydrogen is replaced by methyl; the effect increases with the Mo-C+ distance (75.37, 98.3, and 148.68 ppm for compounds 1, 2, and 3, respectively). This indicates that the back-donation of electron density from the metal onto the ligand makes a substantial
contribution to the stabilization of these cations.
Original Russian Text ? I.V. Barinov, V.A. Chertkov, 2009, published in Vestnik Moskovskogo Universiteta. Khimiya, 2009, No.
1, pp. 29–34. 相似文献
16.
R. G. Gasanov E. V. Martynova M. V. Tsikalova I. V. Stankevich Yu. N. Novikov 《Russian Chemical Bulletin》2010,59(9):1707-1712
The addition of •CCl3 and •But radicals to (η2-C70)Os(CO)(PPh3)2(CNBut) (1) and (η2-C70)[Os(CO)(PPh3)2(CNBut)]2 (3) was studied by ESR spectroscopy. The metal fragment in complex 1 does not influence the regioselectivity of the addition of the radicals to it. The stability of the spin adducts formed upon
addition of free radicals to complexes 1 and 3 is mainly governed by delocalization of the unpaired electron over three hexagonal rings. 相似文献
17.
A quasi-classical trajectory (QCT) calculation with the fourth-order explicit symplectic algorithm for the N(4S) + O2(X3Σg−) → NO(X2Π) + O(3P) reaction has been performed by employing the ground and first-excited potential energy surfaces (PESs). Since the translational
temperature considered is up to 5000 K, the larger relative translational energy and the higher vibrational and rotational
level of O2 molecule have been taken into account. The affect of the relative translational energy, the vibrational and rotational level
of O2 molecule in the reaction cross-sections of the ground and first-excited PESs has been discussed in a extensive range. And
we exhibit the dependence of microscopic rate constants on the vibrational and rotational level of O2 molecule at T = 4000 K. The thermal rate constants at the translational temperature betweem 300 and 5000 K have been evaluated and the
corresponding Arrhenius curve has been fitted for reaction (1). It is found by comparison that the thermal rate constants
determined in this work have a better agreement with the experimental data and provide a more valid theoretical reference. 相似文献
18.
19.
A combined cavity ringdown (CRD) and laser induced fluorescence (LIF) spectroscopic study on the A1∑+-X1∑+ transition of CuH has been presented.The CuH molecule,as well as its deuterated isotopologue CuD,are produced in a supersonic jet expansion by discharging H2(or D2) and Ar gas mixtures using two copper needles.Different profiles of relative line intensities are observed between the measured LIF and CRD spectra,providing an experimental evidence for the predissociation behavior in the A1∑+ state of CuH.The lifetimes of individual upper rotational levels are measured by LIF,in which the J'-dependent predissociation rates are obtained.Based on the previous theoretical calculations,a predissociation mechanism is concluded due to the strong spin-orbit coupling between the A1∑+ state and the lowest-lying triplet 3∑+ state,and a tunneling effect may also be involved in the predissociation.Similar experiments are also performed for CuD,showing that the A1∑+ state of CuD does not undergo a predissociation process. 相似文献
20.
D. A. Loginov A. V. Vologzhanina P. V. Petrovskii M. M. Vinogradov A. R. Kudinov 《Russian Chemical Bulletin》2008,57(8):1653-1656
The reaction of the iodide complex [(η5-C9H2Me5)RhI2]2 (1) or the acetonitrile complex [(η5-C9H2Me5)Rh(MeCN)3]2+ with Tl[Tl(η-7,8-C2B9H11)] afforded rhodacarborane (η5-C9H2Me5)Rh(7,8-C2B9H11) (2). The cationic triple-decker complex with the bridging boratabenzene ligand [Cp*Fe(μ-η:η-C5H3Me2BMe)Rh(η5-C9H2Me5)]2+ (3) was synthesized by the reaction of the nitromethane solvate [(η5-C9H2Me5)Rh(MeNO2)3]2+ with the sandwich compound Cp*Fe(η-C5H3Me2BMe). The structure of 2 was established by X-ray diffraction.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1623–1625, August, 2008. 相似文献