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Abstract  

Isotopic rules are studied for calculated vibrational frequencies of all possible 7212C/13C isotopomers of the C7 cluster of the C2v symmetry. The isotopomers can undergo 486 isomerizations which are decomposed into 27 subclasses using properties of sums of the squares of the vibrational frequencies.

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Abstract  

The labelled compound was prepared by chlorination of [2-14C]acetone obtained from the barium salt of [1-14C]acetic acid by pyrolysis. The reaction product 1,1-dichloro [2-14C]acetone was converted to 2-dichloromethyl-2-methyl [2-14C]-1,3-dioxolane by condensation with ethylene glycol in the presence of thionyl chloride. Radiochemical yield: 62% based on [1-14C]acetic acid.

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Abstract  

The solubility of two n-alkanes in commercial organic liquids, such as diesel fuel and jet fuel represent a problem to industry, because they precipitate in an unpredictable fashion. First we calculated the metastable enthalpy and entropy of fusion of the low temperature forms of the n-alkanes. We analyzed the solubility of alkanes n-C22H46, n-C23H48, n-C24H50 and n-C28H58 in ethylbenzene, m-xylene, n-heptane and gas oil. All systems seem to be close ideal, possibly with a slight positive deviation. We analyzed the solubility at constant temperature of the ternary system solvent C22H46-C24H50, C23H48-C24H50, C13H28-C16H34, C20H42-C22H46, C20H42-C24H50 and C20H42-C28H58, and looked at cloud points in various ternary systems. When the difference in the number of carbon atoms in the two alkanes is small, four or less, a metastable solid solution precipitates from the solvent. If the difference in the number of carbon atoms is six or more, the ‘equilibrium’ phases, or at least phases with low solubility precipitate.

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Abstract  

The yield and average cross section for the reactions11B(p, n)11C,12C(p, )13N,13C(p, n)13N, 12 12 C(d, n)13N,14N(p, )11C,16O(p, )13N,16O(d, n)17F,16O(t, n)18F, and18O(p, n)18F have been measured in different compounds. The charged particles were created in the samples themselves either through recoil by scattering of 14 MeV neutrons off hydrogen and deuterium, or by the (n, t) reaction on6Li using thermal neutrons. The yields of reactions12C(d, n);16O(p, );16O(t, n) and18O(p, n) have been measured using proton, deuteron and triton spectra generated by 14 MeV neutrons in the reactions D(n, p)2n;6Li(n, d);7Li(n, d) and10B(n, d);7Li(n, t) and10B(n, t), respectively.

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Abstract  

The dimeric compound [Pd(bzan)(μ-OOCCH3)]2 (1) (bzan=N-benzylideneaniline) reacts with KX, in methanol/acetone (2:1), affording the analogous dimeric pseudohalogen-bridged species [Pd(bzan)(μ-X)]2 [X=NCO(2),SCN(3), CN(4)]. The compounds were characterized by elemental analysis, infrared spectroscopy, NMR and thermogravimetric analysis. IR data for 2–4 showed bands typical of coordinated pseudohalogen ligands clearly indicating the occurrence of the exchange reaction. Their thermal behaviour was investigated and suggested that their stability is influenced by the bridging ligand. The thermal stability decreased in the order[Pd(bzan)(μ-CN)]2>[Pd(bzan)(μ-SCN)]2>[Pd(bzan)(μ-OOCCH3)]2>[Pd(bzan)(μ-NCO)]2. X-ray results showed the formation of Pd as final decomposition product.

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Abstract

An index system for evaluating academic papers is constructed and verified based on the empirical analysis of papers that has gained the 6th Chinese Academy of Social Sciences Award for Outstanding Achievements. Some new index, such as paper discipline impact factor, discipline average cited rate per paper and discipline average downloaded rate per paper have been put forward in this paper. The empirical research results show that the ranking of papers calculated by this evaluation index system is in conformity with the awards determined by peer review in general, but still needs to be verified and improved in practice.

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Abstract

Except the alphabetic ordering authorship papers, the citations of multi-authored papers are allocated to the authors based on their contributions to the paper. For papers without clarification of contribution proportion, a function of author number and rank is presented to rightly determine the credit allocated proportion and allocated citations of each author. Our citation allocation scheme is between the equally fractional counting and the one using the inverse of author rank. It has a parameter to adjust the credit distribution among the different authors. The allocated citations can either be used alone to indicate one's performance in a paper, or can be applied in the modification of h-index and g-index to represent the achievement of a scientist on the whole. The modified h-index and g-index of an author makes use of more papers in which he or she played important roles. Our method is suitable for the papers with wide range of author numbers.

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The sovereign debt crisis of 2010 in the euro area significantly decelerated the monetary integration of the EU. The main purpose of this paper is to explore whether five post-communist member states of the EU are mature enough to adopt the euro. We used nominal exchange rates in the error correction model with asymmetric power ARCH (ECM-APARCH). Our results highlight that EU membership positively increased the impact of the euro on the currency of each of these countries in the short-run. In contrast, the long-term effect of the euro on each currency is negative for the Czech Republic, Hungary, and Croatia. Wholly different results were obtained for Poland and Romania. The APARCH model showed that the negative responses of the euro had a greater or neutral effect on the conditional variance of each currency instead of the positive responses. The debt crisis of the euro area had no impact on the dynamic linkages between the currencies. Our research concludes that Croatia, the Czech Republic, and Hungary are not ready to join the euro area in the near future. On the other hand, the currencies of Poland and Romania are already aligned with the fluctuations of the euro.

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Acta Chromatographica
Authors: Yun Zhou, Guifeng Huang, Xiaolan Li, Feng Chen, Hong Liu, Ying Yang, Zhong Fan, Jinghui Jiang and Jun Yang

identified as aliphatic, aromatic, and monoterpene compounds were located in the region marked (a)–(c), respectively. Similarly, some components identified as C13-norisoprenoids were located in region (d). The peaks were distributed over the entire

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an aqueous solution containing InCl 3 and SC(NH 2 ) 2 in molar ratio of 1:1 and 1:3. The In(tu) 3 Cl 3 complex was triclinic, with space group P -1, a = 8.519(2) Å, b = 10.555(2) Å, c = 13.325(2) Å, α = 111.30(2)°, β = 99.00(1)°, γ = 97

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