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41.
Ali Dogan Hüseyin Arslan 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(2):332-340
Russian Journal of Physical Chemistry A - However, up to the present, there was few reports on the density of the molten Ag–Au–Cu and Cu–Ag–In alloy systems. In this work,... 相似文献
42.
Khadichakhan Rafikova Nil Ertekin Binbay Nermin Meriç Aygul Kerimkulova Alexey Zazybin Veysel Binbay Veysi Okumuş Cezmi Kayan Uğur Işik Nevin Arslan Murat Aydemir 《应用有机金属化学》2020,34(7):e5658
Four metal complexes, IL-OPPh2-Ru-p-cymene (3) , IL-OPPh2-Ru-benzene (4) , IL-OPPh2-Ir-Cp* (5) , IL-OPPh2-Rh-COD (6) , have been evaluated for in vitro antioxidant activity such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and reducing power activity. Maximum scavenging activity (71.43%) was obtained with IL-OPPh2-Ru-p-cymene, whereas IL-OPPh2-Rh-COD showed the highest reducing power ability. The complexes were also studied for their antimicrobial activity against three Gram-positive and three Gram-negative bacteria. In addition, DNA binding of the complexes was evaluated using calf thymus DNA. Both Ru(II) complexes exhibited good DNA-binding activity while the other complexes did not have any activity. Furthermore, ab initio quantum calculations of four complexes were also carried out using density functional theory to better understand their chemical behaviors. 相似文献
43.
Numerical Algorithms - The k th Fréchet derivative of a matrix function f is a multilinear operator from a cartesian product of k subsets of the space $\mathbb {C}^{n\times n}$ into itself. We... 相似文献
44.
Arslan Asli Ergenekon Arslan Oguz Kandemir Suheyla Yerel 《Journal of Thermal Analysis and Calorimetry》2021,146(3):1191-1192
Journal of Thermal Analysis and Calorimetry - In the original publication of the article, the following equations has been incorrectly published. The corrected equations are given. 相似文献
45.
Hakan Arslan Donald VanDerveer Ismail Ozdemir Bekir Cetinkaya Serpil Demir 《Journal of chemical crystallography》2005,35(6):491-495
Two imidazolidin ruthenium complexes, [RuCl2{[N-(2,4,6-trimethyl-benzyl)-N-(n-butyl)]-imidazolidin-2-ylidene}], 1, and [RuCl2{[N-(2,4,6-trimethyl-benzyl)-N-(2-methoxyethyl)]-imidazolidin-2-ylidene}], 2, have been synthesised and their crystal structures have been determined from single crystal X-ray diffraction data. Compound 1 is monoclinic, of space group C2/c with a = 18.466(4) Å, b = 14.816(3) Å, c = 15.413(3) Å, β = 118.067(2)∘, and V = 3720.9(12) Å3 with Z = 8 for dcalc = 1.536 g/cm3. Compound 2 is monoclinic, of space group P21/c with a = 8.1800(5) Å, b = 14.344(8) Å, c = 14.809(9), β = 91.604(10)∘, and V = 1736.7(18) Å3 with Z = 4 for dcalc = 1.653 g/cm3. In each complex the ligand functions as an arene and carbene, occupying four coordination sites. The two chlorines in each compound complete a distorted octahedron. 相似文献
46.
Abdurrahman Sengul Haydar Arslan Sevgi H. Bayari Orhan Buyukgungor 《Structural chemistry》2008,19(3):467-476
The molecular and crystal structures of 1,2-bis(3,4-dimethoxyphenyl)ethane-1,2-dione (TMBZ = tetramethoxybenzil) were determined by a single-crystal X-ray diffraction, 1H NMR, and FT-IR spectroscopy. The compound TMBZ (C18H18O6, M r = 330.32) crystallized in the orthorhombic Fdd2 space group wherein: a = 39.145(4), b = 18.167(2), c = 4.3139(5) Å and β = 90°, Z = 8. The packing of the molecules in the crystal lattice is stabilized by intermolecular C–H?O contacts in the herringbone arrangement. The molecular geometry and harmonic frequencies of TMBZ in the ground state were calculated utilizing density functional (B3LYP) method with the 6-311++G(d, p)-basis set. The density functional theory optimized the geometric structure, and vibrational wave numbers of TMBZ in gas phase were compared with the experimental data. A complete assignment of the fundamentals was proposed based on the total energy distribution calculation. 相似文献
47.
A method has been described for the determination of iron from fish otoliths containing high levels of calcium by collision cell technology (CCT) ICP-MS. Iron (Fe) in otolith solutions was quantitatively coprecipitated with small amounts of calcium hydroxide by adding 1.0 M sodium hydroxide solution. The performance of CCT-ICP-MS pressurized with He/H(2) cell gas was investigated on the elimination of Ca-based spectral interferences at m/z 54, 56 and 57. Molecular ion interferences at m/z 54 and 56 were reduced by 2 orders of magnitude. However, the interferences at m/z 57 increased by the same amount in the presence of Ca in solutions owing to the formation of (40)Ca(16) OH(+) through reactions with H(2) in collision cell, indicating that (57)Fe was not suitable for the determination of Fe from otoliths. Results for (56)Fe suffered significantly from interferences of Ca-based molecular ions when the Ca concentration in solution exceeded 100 microg ml(-1), for which matrix-matched calibration was required for accurate determination. CCT with the aid of He/H(2) cell gas proved to be very effective in eliminating the interferences ((40)Ar(14)N(+) and (40)Ca(14)N(+)) at m/z 54. Presence of Ca up to 300 microg ml(-1) had virtually no effect on the ion signals of (54)Fe, which with low background signals, afforded accurate determination of Fe from otoliths by using aqueous external standards. 相似文献
48.
We introduce regular expression constrained sequence alignment as the problem of finding the maximum alignment score between given strings and over all alignments such that in these alignments there exists a segment where some substring of is aligned to some substring of , and both and match a given regular expression R, i.e. where is the regular language described by R. For complexity results we assume, without loss of generality, that . A motivation for the problem is that protein sequences can be aligned in a way that known motifs guide the alignments. We present an time algorithm for the regular expression constrained sequence alignment problem where , and t is the number of states of a nondeterministic finite automaton N that accepts . We use in our algorithm a nondeterministic weighted finite automaton M that we construct from N. M has states where the transition-weights are obtained from the given costs of edit operations, and state-weights correspond to optimum alignment scores we compute using the underlying dynamic programming solution for sequence alignment. If we are given a deterministic finite automaton D accepting with states then our construction creates a deterministic finite automaton with states. In this case, our algorithm takes time. Using results in faster computation than using M when . If we only want to compute the optimum score, the space required by our algorithm is ( if we use a given ). If we also want to compute an optimal alignment then our algorithm uses space ( space if we use a given ) where and are substrings of and , respectively, , and and are aligned together in the optimal alignment that we construct. We also show that our method generalizes for the case of the problem with affine gap penalties, and for finding optimal regular expression constrained local sequence alignments. 相似文献
49.
The reactions of N‐dichlorophosphoryl‐P‐trichlorophosphazene Cl3PN P(O)Cl2 ( 1 ) with benzylmagnesium bromide, 2‐phenylethylmagnesium bromide, trimethylsilylmethylmagnesium chloride, n‐butylmagnesium bromide, cyclohexylmagnesium bromide, cyclopentylmagnesium bromide, tert‐butylmagnesium bromide, iso‐propylmagnesium bromide, and ethylmagnesium bromide were studied. Tri‐ and pentaalkyl phosphazenes were obtained in very poor yield from trimethylsilylmethylmagnesium chloride and cyclohexylmagnesium bromide, respectively. Trialkylphosphoryl compounds formed from benzyl‐, 2‐phenylethyl‐, and n‐butylmagnesium bromide. No phosphorus compound could be isolated from the reaction of 1 with t‐butyl‐, cyclopentyl‐, iso‐propyl‐, and ethylmagnesium bromide. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:413–416, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10153 相似文献
50.