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71.
72.
73.
The Pauli coupling
is introduced for four-component neutrino states and related to local T
4SU(2,2) spin-gauge (not internal symmetry) transformations applied to the massless Dirac equation. The well-known left-right asymmetry for free neutrino helicity states is generalised and discussed for Pauli-coupled neutrinos. An explicit exact solution is obtained for Pauli-coupled neutrino equations in an external free radiation field by the use of the above local spin-gauge transformations. It is also suggested that local SL(2, C)SU(2,2) spin-gauge transformations can be used to obtain models of neutral currents for neutrinos. 相似文献
74.
New adducts of ethylenediamine (en), N,N-dimethylethylenediamine (ndmen) and N,N′-dimethylethylenediamine (dmen) with squarate as counter-ions were synthesized and characterized by physico-chemical methods
(IR and UV/vis spectroscopy, magnetic susceptibility and thermoanalytical measurements). The crystal structure of tris(ethylenediamine)cobalt(III)
1.5 squarate hexahydrate, [Co(en)3](sq)1.5 · 6H2O, was determined by single crystal X-ray diffraction. Co(III), Ni(II) and Cu(II) ions in the monomeric octahedral tris(ethylenediamine)cobalt(III)
1.5 squarate hexahydrate (1), tris(ethylenediamine)nickel(II) squarate 0.5 hydrate (2) and diaquabis(ethylenediamine)copper(II) squarate dihydrate (3) are chelated by ethylenediamines through two amine nitrogen atoms. Cu(II) atoms in the diaquabis(ndmen)copper(II) squarate
(4) and diaquabis(dmen)copper(II) squarate (5) monomeric octahedral complexes are coordinated by ndmen and dmen molecules through two amine nitrogen atoms in a bidentate
chelating manner. Water molecules complete the octahedral coordination. The orange (1), violet (4) and violet (5) complexes upon heating transform to claret, green and green species on dehydration, respectively, which revert immediately
after cooling in the open atmosphere. The violet (3) complex upon heating loses water molecules yielding a deep blue dehydrated species, which on further heating undergoes an
exothermic phase transition accompanied by thermochromism, deep blue to brown in the solid state. The decomposition mechanism
and thermal stability of the solid complexes are interpreted in terms of their structures. The final decomposition products
– the respective metal oxides – were identified by IR spectroscopy. 相似文献
75.
In this paper, we first consider a generalization of Kim’s -adic -integral on including parameters and . By using this integral, we introduce the -Daehee polynomials and numbers with weight . Then, we obtain some interesting relationships and identities for these numbers and polynomials. We also derive some correlations among -Daehee polynomials with weight , -Bernoulli polynomials with weight and Stirling numbers of second kind. 相似文献
76.
B. Harihara Venkatraman Piyali D. Chaudhuri Serkan Yurt D. Venkataraman 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):983-985
In this paper, we show a common strategy to synthesize tetraalkenylmethanes, a cross-linker series for building three-dimensional hydrocarbon networks. To demonstrate the feasibility of this method, we have synthesized tetrapentenylmethane. Attempts to synthesize this cross-linker from pentaerythrityl tetrabromide using substitution reactions resulted in the formation of a spiro compound due to intramolecular cyclization. We also show that the difficulty in reactions at the neopentyl carbon site is due to the neopentyl carbanion stability, not the sterics. 相似文献
77.
Beşli S Davies DB Kiliç A Shaw RA Sahin S Uslu A Yeşilot S 《Journal of chromatography. A》2006,1132(1-2):201-205
High-performance liquid chromatographic (HPLC) methods have been developed for investigating the stereogenic properties of two analogous series of dibenzylamino derivatives of cyclotriphosphazene containing either one or two equivalent stereogenic centres. Separation of the enantiomers of all the racemic compounds has been investigated by chiral HPLC using Whelk-01 and Chiralcel OD columns. In all cases, conditions for separation of enantiomers have been found using a Whelk-01 column with different ratios of tetrahydrofuran in n-hexane as the mobile phase. It is found that both the separation factor (alpha) and resolution factor (R(S)) of molecules with two equivalent stereogenic centres are greater than those for analogues with only one centre. 相似文献
78.
Serkan Eryilmaz 《Methodology and Computing in Applied Probability》2018,20(2):563-573
A new scheme-distribution-based representation is presented for the cumulative distribution function of the number of success runs of length k in a sequence of exchangeable binary trials. By utilizing this new representation, some stochastic ordering results are obtained to compare success runs. The results are illustrated for beta-binomial distributions of order k. 相似文献
79.
An on-line preconcentration/separation system for the determination of bismuth in environmental samples by FAAS 总被引:1,自引:0,他引:1
An on-line preconcentration procedure for the determination of bismuth by flame atomic absorption spectrometry (FAAS) has been described. Lewatit TP-207 chelating resin, including iminodiacetate group, packed in a minicolumn was used as adsorbent material. Bi(III) was sorbed on the chelating resin, from which it could be eluted with 3 mol L−1 HNO3 and then introduced directly to the nebulizer-burner system of FAAS. Best preconcentration conditions were established by testing different resin quantities, acidity of sample, types of eluent, sample and eluent solution volumes, adsorption and elution flow rates, and effect of interfering ions. The detection limit of the method was 2.75 μg L−1 while the relative standard deviation was 3.0% for 0.4 μg mL−1 Bi(III) concentration. The developed method has been applied successfully to the determination of bismuth in pharmaceutical cream, standard reference materials and various natural water samples with satisfactory results. 相似文献
80.
Serkan Soylu Murat Ta Hanife Sarao
lu Hümeyra Bat Nezihe alkan Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o115-o117
The structure of the title compound, C16H16N2O2, consists of a dimeric arrangement around an inversion centre of acetamidine molecules linked via O—H⋯N hydrogen bonds. There are also H⋯π‐ring interactions. All these interactions result in the formation of infinite chains parallel to the (101) axis. The oxime group has an E conformation. 相似文献