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141.
A. Yu. Fedorov J. -P. Finet O. G. Ganina M. I. Naumov A. S. Shavyrin 《Russian Chemical Bulletin》2005,54(11):2602-2611
Benzopyran derivatives were synthesized in good yields by the reactions of tris[2-(chloromethyl)phenyl]bismuth diacetate and
2-(halomethyl)aryllead triacetates with phenols and naturally occurring 4-hydroxycoumarins in the presence of bases according
to a three-step one-pot procedure.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2520–2529, November, 2005. 相似文献
142.
Modification of Paving Asphalts with Sulfur 总被引:2,自引:0,他引:2
Syroezhko A. M. Begak O. Yu. Fedorov V. V. Gusarova E. N. 《Russian Journal of Applied Chemistry》2003,76(3):491-496
Sulfur dissolved in oil components of asphalt is a binder, filler, and chemical co-reagent at once. The structure of sulfur-extended asphalt depends on its formula and heating temperature. Road pavement based on sulfur-extended asphalt demonstrates higher durability as compared to that with the conventional binders. 相似文献
143.
JETP Letters - A constraint $$g_{A}^{2}\leq 4.5\times10^{-24}\big(g^{2}+1/\lambda_{A}^{2}\big)$$ on the constant gA of a new short-range (spin—orbit) interaction between nucleons, which is... 相似文献
144.
Yoshimura T Chen ZN Itasaka A Abe M Sasaki Y Ishizaka S Kitamura N Yarovoi SS Solodovnikov SF Fedorov VE 《Inorganic chemistry》2003,42(16):4857-4863
Hexarhenium(III) complexes with terminal isothiocyanate ligands, [(n-C(4)H(9))(4)N](4)[Re(6)(mu(3)-S)(8)(NCS)(6)] (1) and (L)(4)[Re(6)(mu(3)-Se)(8)(NCS)(6)] (L(+) = PPN(+) (2a), (n-C(4)H(9))(4)N(+) (2b)), have been prepared by three different methods. Complex 1 was prepared by the reaction of [(n-C(4)H(9))(4)N](4)[Re(6)(mu(3)-S)(8)Cl(6)] with molten KSCN at 200 degrees C, while 2b was obtained by refluxing the chlorobenzene-DMF (2:1 v/v) solution of [Re(6)(mu(3)-Se)(8)(CH(3)CN)(6)](SbF(6))(2) and [(n-C(4)H(9))(4)N]SCN. The [Re(6)(mu(3)-Se)(8)(NCS)(6)](4)(-) anion was also obtained from a mixture of Cs(2)[Re(6)(mu(3)-Se)(8)Br(4)] and KSCN in C(2)H(5)OH by a mechanochemical activation at room temperature for 20 h and isolated as 2a. The X-ray structures of 1 and 2a.4DMF have been determined (1, C(70)H(144)N(10)S(14)Re(6), monoclinic, space group P2(1)/n (No. 14), a = 14.464(7) A, b = 22.059(6) A, c = 16.642(8) A, beta = 113.62(3) degrees, V = 4864(3) A(3), Z = 2; 2a.4DMF, C(162)H(144)N(14)O(4)P(8)S(6)Se(8)Re(6), triclinic, space group P1 (No. 2), a = 15.263(2) A, b = 16.429(2) A, c = 17.111(3) A, alpha = 84.07(1) degrees, beta = 84.95(1) degrees, gamma = 74.21(1) degrees, V = 4098.3(8) A(3), Z = 1). All the NCS(-) ligands in both complexes are coordinated to the metal center via nitrogen site with the Re-N distances in the range of 2.07-2.13 A. The redox potentials of the reversible Re(III)(6)/Re(III)(5)Re(IV) process in acetonitrile are +0.84 and +0.70 V vs. Ag/AgCl for [Re(6)(mu(3)-S)(8)(NCS)(6)](4)(-) and [Re(6)(mu(3)-Se)(8)(NCS)(6)](4)(-), respectively, which are the most positive among the known hexarhenium complexes with six terminal anionic ligands. The complexes show strong red luminescence with the emission maxima (lambda(max)/nm), lifetimes (tau(em)/micros), and quantum yields (phi(em)) being 745 and 715, 10.4 and 11.8, and 0.091 and 0.15 for 1 and 2b, respectively, in acetonitrile. The data reasonably well fit in the energy-gap plots of other hexarhenium(III) complexes. The temperature dependence of the emission spectra and tau(em) of 1 and [(n-C(4)H(9))(4)N](4)[Re(6)(mu(3)-S)(8)Cl(6)] are also reported. 相似文献
145.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献
146.
Yu. V. Mironov N. G. Naumov Sung-Jin Kim V. E. Fedorov 《Russian Journal of Coordination Chemistry》2007,33(4):279-285
Two cyano-bridged compounds of novel dodecanuclear cluster anion [Re12CS17(CN)6] with Ni2+ cations were synthesized, namely, one-dimensional polymer of the composition [{Ni(NH3)4} {Ni(NH3)5}2Re12CS17(CN)6] · 7H2O (I) with a chain structure and [Ni(NH3)6]3[{Ni(NH3)4}3 {Re12CS17(CN)6}2] · 21H2O (II), containing the anionic dimeric complex [{Ni(NH3)4}3 {Re12CS17(CN)6}2]6?. The structures of both compounds were established by X-ray diffraction analysis. Crystals I are monoclinic, space group P2/n, a = 15.321(3), b = 12.635(2), c = 15.448(3) Å, β = 100.242(3)°, V = 2942.8(8) Å3, Z = 2. Crystals II are trigonal, space group R3, a = b = 19.7987(14), c = 28.8642(18) Å, V = 9798.6(12) Å3, Z = 3. 相似文献
147.
13
C NMR spectra of some azole series have been investigated: 2-pyridylbenzimidazoles, 2-pyridylimidazo [4,5-b]-pyridines, 2-pyridylimidazo[4,5-c]-pyridines, analogous oxazole compounds, as well as their mono- and bisquaternary salts. Some problems, related to the structure of these compounds in solution, have been discussed.V. I. Vernadskii Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow 117975. Torino University, Italy. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 866–872, April, 1992. 相似文献
148.
O. A. Efremova Yu. V. Mironov D. Yu. Naumov V. E. Fedorov 《Journal of Structural Chemistry》2006,47(4):740-744
Three novel cluster compounds K4[Re4STe3(CN)12]·4H2O (I), [{Cu(en)2}2Re4STe3(CN)12]·5H2O (II) and [{Cu(trien)}2Re4STe3(CN)12]·2H2O (III) (en is ethylenediamine, trien is triethylenetetraamine) containing a new cluster core {Re4STe3} have been prepared and structurally characterized. According to single crystal X-ray diffraction data, compound I is ionic and represents the arrangement of ions K+ and [Re4STe3(CN)12]4?; compounds II and III are molecular and formed by two cationic moieties {Cu(en)2}2+ and {Cu(trien)}2+, respectively, coordinated to one cluster anion. In the solid state, S atom positions in the tetrahedron Q4 (Q = S, Te) are disordered for all three compounds: in I and III sulfur atoms are split over all four Q positions, while in II over two positions. 相似文献
149.
V. I. Dostovalova L. A. Fedorov Y. Knuutinen E. Kolehmainen J. Paasivirta 《Russian Chemical Bulletin》1994,43(4):566-573
A two-particle system of OY-Cl and OY-Br mixed increments for predicting13C NMR chemical shifts of polyhalogenated polyoxybenzenes has been developed. It has been found that only theortho- and para-interactions of the OY and Hal substituents contribute significantly to the13C chemical shifts and that theortho-effects of the OY located between Ha1 and H and those of the OY located between two Ha1 atoms are different. Additional effects are due to solvating solvents. The increment scheme is predictive over the whole class of compounds under consideration and may be realized on personal computers.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 617–624, April, 1994. 相似文献
150.
A. I. Rebrov L. A. Fedorov I. I. Antokol'skaya G. V. Myasoedova 《Journal of Structural Chemistry》1991,32(2):215-219
The special features of the chemical structure of polymeric complex-forming sorbents obtained on the basis of various polymeric matrices with a macroporous structure and pyrazole derivatives have been investigated with the aid of solid-state high-resolution13C NMR spectroscopy (MAS/CP/DD). The signals of the atoms in individual structural fragments of the polymeric matrices and the complex-forming groups have been identified, and the form of the complex-forming groups in the sorbent and the form in which they appear in the polymeric matrix have been established.V. I. Vernadskii Institute of Geochemistry and Analytical Chemistry, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 32, No. 2, pp. 72–78, March–April, 1991. 相似文献