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71.
L. A. Lapkina S. G. Sakharov V. E. Larchenko Yu. G. Gorbunova A. Yu. Tsivadze 《Russian Journal of Inorganic Chemistry》2007,52(4):543-550
The cation-induced aggregation of sandwich crown-substituted complexes [Ln(R4Pc)2] (Ln = Lu (I) and Yb (II), R4Pc2? is the 4,5,4′,5′,4″,5″,4?,5?-tetrakis(1,4,7,10,13-pentaoxatridecamethylene)phthalocyaninate ion) and Ln2(R4Pc)3(Ln = Lu (III) and Yb (IV) in a CDCl3-DMSO-d 6 solution has been studied by 1H NMR. The data obtained are consistent with the conclusions concerning the composition of supramolecular aggregates drawn from spectrophotometric titration data. The molecules of double-decker complexes I and II form supramolecular oligomers, whereas triple-decker complexes III and IV form supramolecular dimers, which is presumably due to the stronger distortion of the planes of the outer decks of the triple-decker complexes as compared to their double-decker analogues. 相似文献
72.
K. P. Birin Yu. G. Gorbunova A. Yu. Tsivadze 《Russian Journal of Inorganic Chemistry》2007,52(2):191-196
Praseodymium(III) complexes with tetra-15-crown-5-phthalocyanine—the neutral radical [(R4Pc?·)Pr3+(R4Pc2?)]0 and one-electron reduced [(R4Pc2?)Pr3+(R4Pc2?)]? forms of the sandwich double-decker complex and the triple-decker complex Pr2(R4Pc)3 (R4Pc2? is [4,5,4′,5′,4″,5t",4″′,5″′-tetrakis(1,4,7,10,13-pentaoxatridecamethylene)phthalocyaninate ion])—have been synthesized and spectrally characterized. These compounds have been obtained by direct interaction of tetra-15-crown-5-phthalocyanine with praseodymium(III) acetate or acetylacetonate. The salt anion has an effect on the yield and structure of the reaction products. The complexes have been obtained in high yields, isolated, and characterized by different physicochemical methods: UV and visible electronic absorption spectroscopy, 1H NMR, and MALDI-TOF mass spectrometry. The double-decker complex is stable in the solid state and in solutions. The triple-decker complex is stable only in the solid state. In a chloroform-methanol (10 vol %) solution, it slowly decomposes. 相似文献
73.
Olga Kovalenko Vladimir Baulin Dmitriy Baulin Aslan Tsivadze 《Molecules (Basel, Switzerland)》2021,26(9)
Novel solvent-impregnated resins (SIRs) were prepared by treatment of styrene–divinylbenzene copolymer (LPS-500) with mixtures of the promising polydentante extractant (2-diphenylphosphoryl)-4-ethylphenoxy)methyl)diphenylphosphine oxide (L) and an ionic liquid [C4mim]+[Tf2N]−for the extraction chromatography recovery of Nd(III) from nitric acid solutions. It was shown that introduction of the ionic liquid into the SIR composition results in considerable enhancement of the Nd(III) recovery efficiency compared with resin impregnated only by L in slightly acidic media. The influence of the L: ionic liquid molar ratio in the SIRs composition, their percentages, concentration of metal and HNO3 in the eluent, and acid type on the value of synergistic effect and adsorption efficiency of Nd(III) recovery was studied. The SIR containing 40% of mixture of L and [C4mim]+[Tf2N]− with molar ratio 2:1 turned out to be the most efficient. The selectivity of Nd(III) separation from light and heavy rare-earth elements was studied and the optimal conditions of Nd(III) adsorption recovery and stripping by this SIR were chosen. It was found that in recovery efficiency of Nd(III) developed SIR exceeded the SIR containing Cyanex 923 (a mixture of monodentate trialkylphosphine oxides) and [C4mim]+[Tf2N]−. 相似文献
74.
A. N. Turanov V. K. Karandashev I. P. Kalashnikova V. E. Baulin A. Yu. Tsivadze 《Russian Journal of Inorganic Chemistry》2017,62(9):1252-1256
Interfacial distribution of micro amount of ReO4 - between aqueous solutions of mineral acids and solutions of 2-phosphorylphenoxyacetamides in dichloroethane has been studied. Stoichiometry of extracted complexes has been determined; the effect of HNO3, HCl, and H2SO4 concentration in aqueous phase, extractant structure, and organic solvent nature on the efficiency of ReO4 - ions transfer into organic phase has been considered. It has been shown that Re(VII) can be selectively recovered and concentrated with complexing sorbent obtained by the noncovalent binding of 2-[2-(diphenylphosphoryl)-4-ethylphenoxy]-N,N-dioctylacetamide on the surface of macroporous polymer Amberlite XAD7HP. 相似文献
75.
A. Yu. Tsivadze M. R. Tarasevich E. A. Maleeva V. E. Baulin I. P. Kalashnikova 《Russian Chemical Bulletin》2015,64(10):2386-2392
The kinetics of catalytic electroreduction of oxygen in a 1 N KOH solution was studied by the rotating disk electrode (RDE) method. Azamacrocyclic iron and ruthenium complexes of the porphyrin and phtalocyanine series were used as catalysts. The reduction of oxygen was also studied on both the individual complexes and the same complexes supported on carbon supports (XC72R and graphene). The catalytic activity and selectivity of the complex is determined, to a high extent, by the nature and electron-donor properties of the metal atom in the complex and, to a lesser extent, by the structure of the organic ligand. 相似文献
76.
V. E. Baulin M. A. Kiskin I. S. Ivanova E. N. Pyatova D. V. Baulin A. Yu. Tsivadze 《Russian Journal of Coordination Chemistry》2011,37(6):405-410
The complex [Li(H3L2)(H2O)] n (I), where H4L2 is 1,5-bis[2-(dioxyphosphinyl)phenoxy]-3-oxapentane, is synthesized. Its crystal and molecular structures are determined by X-ray diffraction analysis and vibrational spectroscopy. Complex I is an isolated chain polymer in which the Li+ cations bind anions (H3L2)? of the bridging ligand. The crystals are orthorhombic: a = 8.1860(3) Å, b = 9.9093(4) Å, c = 23.6293(8) Å, V = 1916.75(12) Å3, Z = 4, space group Pna2 1. The framework of the polymer chain is stabilized by hydrogen bonds between two hydrogen atoms of the coordinated water molecule and two oxygen atoms of the ether and phosphone groups. 相似文献
77.
Aluminum(iii) and magnesium(ii) porphyrinates were synthesized starting from free base meso-tetra(benzo-15-crown-5)porphine (H2TCP), AlCl3, and Et2O??MgBr2. The structures of the compounds obtained were determined by NMR spectroscopy, electronic absorption spectroscopy (EAS), and MALDI TOF mass spectrometry. A comparative analysis of the fluorescence properties of MgTCP, Al(OH)TCP, and H2TCP and of stabilities of the metal porphyrinates in an aqueous solution in a wide pH range was carried out. The receptor properties of aluminum(iii) porphyrinate to potassium cations in an aqueous solution were examined by the changes in the EAS and fluorescence spectra. 相似文献
78.
A. Yu. Tsivadze A. G. Martynov M. A. Polovkova Yu. G. Gorbunova 《Russian Chemical Bulletin》2011,60(11):2258-2262
A novel approach to heteroleptic heteronuclear rare earth metal(III) trisphthalocyaninates was proposed with the complexes [(15C5)4Pc]M*[(15C5)4Pc]M(Pc) as examples (15C5 is 15-crown-5, Pc2? is the phthalocyaninate dianion, and M* ?? M = Yb and Y). Unsubstituted lanthanum bisphthalocyaninate, La(Pc)2, was used for the first time as a Pc2? donor in the synthesis of such complexes. This substantially increased the yields of the target heteronuclear complexes over the previous literature data. 相似文献
79.
N. N. Popova V. I. Zhilov S. V. Demin A. Yu. Tsivadze V. V. Yakshin O. M. Vilkova 《Russian Journal of Inorganic Chemistry》2011,56(7):1128-1132
Americium sorption by crown-ether-impregnated polymeric sorbents from nitric acid solutions and multicomponent nitrate solutions
that model process solutions was studied. Sorption of ballast elements by the unimpregnated Porolas-T support was studied.
The sorption coefficients K
d
of these elements on Porolas-T do not exceed 0.01. Sorption of the same elements by crown-ether-impregnated sorbents was
also studied. Dicyclohexano-18-crown-6 (DCH18C6) and its alkyl derivatives were used. Sorption coefficients were determined
for all ballast elements. At the final stage of the study, 241Am sorption coefficients of from multi-component solutions were determined. The data obtained signify the utility of crown-ether-impregnated
sorbents for recovering 241Am from multicomponent technological solutions. 相似文献
80.
V. V. Yakshin N. A. Tsarenko A. M. Koshcheev A. Y. Tsivadze 《Russian Journal of Inorganic Chemistry》2011,56(12):1997-2000
The extraction recovery of uranium from 1–10 mol/L hydrochloric acid solutions into solutions of alkylated crown ethers di-tert-butyldibenzo-18-crown-6 (DTBDB18C6) and di-tert-butyldicyclohexyl-18-crown-6 (DTBDCH18C6) in organic solvents (nitrobenzene, 1,2-dichloroethane, chloroform, 1-octanol) was
studied. It was found that with increasing HCl concentration, the value of the distribution coefficients of uranium (D) between the organic and aqueous phases increased to a maximum value at 9 mol/L HCl for DTBDB18C6 and 6–7 mol/L HCl for DTBDCH18C6.
The properties of the solvent also greatly affect the values of D, reaching a maximum in the application of nitrobenzene, dichloroethane, or their mixture. Under these conditions, D for a 0.01 mol/L solution of DTBDCH18C6 in nitrobenzene is 830, which is the highest of known values. It was determined by
the slope method and the complete saturation method that the extracted complexes of the studied alkylated crown ethers with
uranyl ions have the 2 : 1 composition. Thus, new supramolecular extractants of uranium from hydrochloric acid solutions have
been studied, having an extremely high extraction capacity, which can be used in the analytical and preparative chemistry
of uranium. 相似文献