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61.
O. LeynaudA. Lafond Y. MoëloP. Palvadeau A. Meerschaut 《Journal of solid state chemistry》2002,168(1):41-51
Crystal structures of two new misfit compounds, [SrGd0.5S1.5]1.16NbS2 and [Sr(Fe,Nb)0.5S1.5]1.13NbS2, were determined through the composite approach, i.e., by refining each subpart (Q, H-parts, and the common part) of these composite materials, separately. The Q-part is a three-atom-thick layer, with the NaCl-type structure, where external SrS planes enclose the inner GdS or (Fe,Nb)S plane; the structural difference between these two compounds lies in the central layer within the Q-part: Gd and S atoms are in special positions (octahedral coordination), while Fe and S atoms are statistically distributed on split (×4) positions (tetrahedral coordination) around a central unique site (=special position occupied by Nb). The H-part is a sandwich of sulfur planes enclosing the inner Nb plane as observed for the structure of the binary compound NbS2 itself. The Sr-Gd derivative shows a paramagnetic behavior in the whole studied temperature range (2-300 K). On the other hand, antiferromagnetic interactions occur in the Sr-Fe derivative; the complex magnetic behavior of this compound is related to the statistical distribution of Fe atoms which leads to frustration of the magnetic interactions. At room temperature, experimental values obtained from Mössbauer spectrum correspond to Fe3+ in tetrahedral sulfur environment: isomer shift δ=0.32 mm s−1, and quadrupole splitting ΔE=0.48 mm s−1. 相似文献
62.
O. A. Kholdeeva R. I. Maksimovskaya G. M. Maksimov K. I. Zamaraev 《Reaction Kinetics and Catalysis Letters》1998,63(1):95-102
Alkylammonium salts of Ti(IV)-substituted heteropolytungstate, PW11TiO
10
5−
, catalyze the oxidation of methyl phenyl sulfide with hydrogen peroxide. The yield of the corresponding sulfoxide and sulfone
is practically quantitative. A31P NMR study confirms the formation and reactivity of the PW11O39TiO
2
5−
peroxo complex in organic media. 相似文献
63.
ZnS胶体溶液中某些无机盐光化学过程中产生的阴离子自由基的ESR研究 总被引:4,自引:0,他引:4
本文用自旋捕捉与ESR技术相结合的方法研究了ZnS胶体溶液中某些无机盐光化学过程中产生的无机阴离子自由基,并对自由基产生的机理进行了讨论 相似文献
64.
Photocatalytic reactions occurring at semiconductor particles/solution interfaces can be applied to organic syntheses. In this review article, examples of photocatalytic syntheses of cyclic amino acids by suspended semiconductor particles, e.g., titanium(IV) oxide or cadmium(II) sulfide are introduced and interpreted. Different from the photocatalytic decomposition of pollutants under aerobic conditions, selective conversion of organic compounds can be driven by the photocatalytic reactions under deaerated conditions. 相似文献
65.
A New Samarium Nitride Sulfide: Sm4N2S3 The oxidation of samarium with sulfur in the presence of SmCl3 and NaN3 as nitrogen source (molar ratio: 12:9:4:2, evacuated silica vessel, some NaCl as flux, 850°C, 7 d) yields Sm4N2S3 as lath-shaped, dark red single crystals. The by-products (NaCl and NaSm2Cl6) are rinsed with water from the crude product. The crystal structure of Sm4N2S3 (monoclinic, C2/m (no. 12), Z = 2, a = 1 318.04(12), b = 391.57(2), c = 1 031.76(9) pm, β = 130.874(6)°, R = 0.036, Rw = 0.031) contains two crystallographically different Sm3+, both in sixfold coordination of the anions. Besides distorted octahedra [(Sm1)N3S3] and [(Sm2)NS5], tetrahedra [(N3?)(Sm)] connected via two cis-oriented edges to form chains [N(Sm1)3/3(Sm2)1/1]3+ build up the Mayn structural feature. These are arranged in the fashion of a closest packing of rods and held together by two crystallographically different S2? anions which take care for charge neutrality and three-dimensional interconnection. 相似文献
66.
M4X3[Si2O7]-Type Lanthanide Chalcogenide Disilicates (M ? Ce? Er; X ? S, Se) Attempts to produce single crystals of MSe2 (or MSe2?X) by vapour phase transport with iodine or the oxidation of MCl2 (or MClH) with sulfur in the presence of NaCl in sealed evacuated quartz containers often yielded well-grown single crystals with the composition M4X3[Si2O7] (M ? pr, Sm, Gd, X ? Se, and M ? Nd, Er, X ? S) as by-products. The crystal structures (tetragonal, 141/amd (no. 141)), Z = 8, contain two crystallographically independent M3+ Cations that are interconnected by chalcogenide (X2?) and disilicate anions ([Si2O7]6?). (M1)3+ is surrounded by eight (five X2? and three terminal O2? of the disilicate group), (M2)3+ by nine (three X2? and six terminal O2? of the [Si2O7]6? anion) chalcogenide anions. The disilicate anion itself exhibits the eclipsed conformation with non-linear Si? O? Si bridges (angles: 128 – 133°). 相似文献
67.
A. S. Balueva A. S. Dokuchaev S. R. Prokhorova A. P. Filippova G. N. Nikonov 《Russian Chemical Bulletin》1993,42(8):1381-1384
X-Ray study of the (3,5-diallylisocyanuratomethyl)bis(chloromethyl)phosphine oxide showed that the phosphorylmethyl group is bonded to the nitrogen atom of the cycle. Reaction of the tris(chloromethyl)phosphine sulfide with sodium diallylisocyanurate gave (3,5-diallylisocyanuratomethyl)bis(chloromethyl)phosphine sulfide, and treatment of the tris(3,5-diallylisocyanuratomethyl)phosphine oxide with phosphorus pentasulfide gave a tris(3,5-diallylisocyanuratomethyl)bis(chloromethyl)phosphine sulfide.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1446–1448, August, 1993. 相似文献
68.
The effectiveness of applying a pulsed corona discharge to the destruction of olfactory pollution in air was investigated.
This paper presents a comparative study of the decomposition of three representative sulfide compounds in diluted concentrations:
hydrogen sulfide (H2S), dimethyl sulfide (DMS), and ethanethiol (C2H5SH), which could be completely removed when a sufficient but reasonable energy density was deposited in the gas. DMS showed
the lowest energy cost (around 30 eV/molecules); C2H5SH and H2S had an EC of respectively 45 eV and 115 eV. The efficiency of the non-thermal plasma process increased with decreasing the
initial concentration of sulfide compounds, while the energy yield remained almost unchanged. SO2 was the only identified byproduct of H2S decomposition, but the sulfur balance suggests the formation of undetected SO3. The byproducts analyzed during the degradation of DMS and C2H5SH enabled to propose a reaction mechanism, starting with radical attack and breaking of C–S bonds. 相似文献
69.
Walrand J Lengelé M Blanquet G 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(14):3299-3303
Using diode-laser spectroscopy, the intensities of 58 lines of the v(1) + v(1/2) - v(1/2) band and 36 lines of the 2v(1) - v(1) band of OCS have been measured. The corresponding band strengths S(0)(v) and the vibrational transition dipoles micro(v) have been derived through least squares fitting of these individual intensities. The band strengths values have been determined with a precision better than 2.5%. 相似文献
70.