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121.
Mahdiyeh Bamdad Hossein Farrokhpour Bijan Najafi Mahmud Ashrafizaadeh 《Structural chemistry》2018,29(6):1745-1751
In this work, the interaction of three Li+-doped polycyclic hydrocarbons (Li+-DPH) with H2 and H2O was calculated to investigate the effect of curvature of substrate on the interaction energy (Eint). For this purpose, the Eint and its decomposed energy components (electrostatic (Eelec), exchange (Eexch), induction (Eind), and dispersion energy (Edisp)) were calculated using DF-SAPT (DFT) methodology for the selected systems (Li+-(3,3) carbon nanotube (Li+-CNT33), Li+-(6,6) carbon nanotube (Li+-CNT66), and Li+-graphene). According to the results, Eint does not change significantly with curvature for the interaction between both H2 and H2O gases and the selected Li+-DPH. Since the variation of the Eint with the curvature of Li+-DPH is not significant, the selection of a planar Li+-DPH is a trustworthy model to develop a general force field for describing the interaction between a Li+-DPH and adsorbed gases. The results reveal that, in the case of the H2, the components Eelect, Eexch, Eind, and Edisp have shown a decreasing trend with Li+-DPH’s curvature decrement. However, for the H2O, Eelect, Eexch, and Eind decrease from the Li+-CNT33 to the Li+-CNT66 while they increase from the Li+-CNT66 to the Li+-graphene. In this case, the Edisp increases with a decrease of the curvature of Li+-DPH. Finally, it can be seen that although the variation of the Eint with the curvature of Li+-DPH is not significant, the variation trend of the interaction energy components and the amount of variation depend on the gas molecule and in some cases are not negligible. 相似文献
122.
Pargari Maryam Marahel Farzaneh Goodajdar Bijan Mombeni 《Journal of Analytical Chemistry》2022,77(4):484-494
Journal of Analytical Chemistry - In this study, a simple, accurate, precise, rapid, economical, and highly sensitive ultraviolet spectrophotometric method has been developed for the determination... 相似文献
123.
Hydroboration of Alkynes with Zwitterionic Ruthenium–Borate Complexes: Novel Vinylborane Complexes 下载免费PDF全文
R. S. Anju Bijan Mondal Koushik Saha Subir Panja Babu Varghese Prof. Sundargopal Ghosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(32):11393-11400
Building upon previous studies on the synthesis of bis(sigma)borate and agostic complexes of ruthenium, the chemistry of nido‐[(Cp*Ru)2B3H9] ( 1 ) with other ligand systems was explored. In this regard, mild thermolysis of nido‐ 1 with 2‐mercaptobenzothiazole (2‐mbzt), 2‐mercaptobenzoxazole (2‐mbzo) and 2‐mercaptobenzimidazole (2‐mbzi) ligands were performed which led to the isolation of bis(sigma)borate complexes [Cp*RuBH3L] ( 2 a – c ) and β‐agostic complexes [Cp*RuBH2L2] ( 3 a – c ; 2 a , 3 a : L=C7H4NS2; 2 b , 3 b : L=C7H4NSO; 2 c , 3 c : L=C7H5N2S). Further, the chemistry of these novel complexes towards various diphosphine ligands was investigated. Room temperature treatment of 3 a with [PPh2(CH2)nPPh2] (n=1–3) yielded [Cp*Ru(PPh2(CH2)nPPh2)‐BH2(L2)] ( 4 a – c ; 4 a : n=1; 4 b : n=2; 4 c : n=3; L=C7H4NS2). Mild thermolysis of 2 a with [PPh2(CH2)nPPh2] (n=1–3) led to the isolation of [Cp*Ru(PPh2(CH2)nPPh2)(L)] (L=C7H4NS2 5 a – c ; 5 a : n=1; 5 b : n=2; 5 c : n=3). Treatment of 4 a with terminal alkynes causes a hydroboration reaction to generate vinylborane complexes [Cp*Ru(R?C?CH2)BH(L2)] ( 6 and 7 ; 6 : R=Ph; 7 : R=COOCH3; L=C7H4NS2). Complexes 6 and 7 can also be viewed as η‐alkene complexes of ruthenium that feature a dative bond to the ruthenium centre from the vinylinic double bond. In addition, DFT computations were performed to shed light on the bonding and electronic structures of the new compounds. 相似文献
124.
Das B Maitra B Mercer SM Everist M Leaist DG 《Physical chemistry chemical physics : PCCP》2008,10(21):3083-3092
Taylor dispersion is used to measure ternary mutual diffusion coefficients (D(ik)) for aqueous solutions of decylsulfobetaine (SB10) (1) + dodecylsulfobetaine (SB12) (2), SB10 (1) + SB14 (2), and SB12 (1) + SB14 (2) mixed zwitterionic micelles. Cross-coefficient D(21) for the coupled flow of surfactant 1 produced by a concentration gradient in surfactant 2 is relatively small for these solutions, but D(12) reaches values as large as the main D(ii) coefficients. The results are interpreted by using the equation D(ik) = partial differential(C(i)D(i))/ partial differentialC(k) to relate the ternary mutual diffusion coefficients to the concentration-weighted average diffusion coefficients D(i) of the micellar and free-monomer forms of the surfactants. The macroscopic-gradient Taylor measurements are compared with diffusion coefficients measured by dynamic light scattering (DLS), which monitors microscopic concentration fluctuations. At most compositions, the intensity autocorrelation function G(tau) is a single exponential decay in D((2)), the smaller eigenvalue of the mutual diffusion coefficient matrix. A contribution from D((1)) is identified at high solute fractions of surfactant 1. The DLS results are consistent with contributions to G(tau) from uncoupled fluctuations in the concentrations of eigencomponents defined as the linear combinations of surfactants 1 and 2 that diagonalize the D(ik) matrix. A procedure for the rapid and convenient DLS measurement of ternary mutual diffusion coefficients, including the cross-coefficients for coupled diffusion, is suggested, using the Onsager reciprocal relation together with the eigenvalues and pre-exponential factors from G(tau). 相似文献
125.
Gurubasavaraj PM Roesky HW Nekoueishahraki B Pal A Herbst-Irmer R 《Inorganic chemistry》2008,47(12):5324-5331
The reaction of LAlMeOH [L = CH(N(Ar)(CMe))2, Ar = 2,6-i-Pr2C6H3] with CpTiMe3, Cp*TiMe3, and Cp*ZrMe3 was investigated to yield LAlMe(mu-O)TiMe2Cp (2), LAlMe(mu-O)TiMe2Cp* (3), and LAlMe(mu-O)ZrMe2Cp* (4), respectively. The resulting compounds 2-4 are stable at elevated temperatures, in contrast to their precursors such as CpTiMe3 and Cp*ZrMe3, which already decompose below room temperature. Compounds 2-4 were characterized by single-crystal X-ray structural analysis. Compounds 2 and 3 were tested for ethylene polymerization in the presence of methylaluminoxane. The half-metallocene complex 3 has higher activity compared to 2. The polydispersities are in the range from 2.8 to 4.2. A copolymerization with styrene was not observed. 相似文献
126.
The reaction of 2,2‐oxydiethanethiol and 2‐[2‐mercaptoethyl) thio] ethanethiol with dichloroglyoxime (DCGO) in absolute EtOH led to crown compounds, oxadithia (5Z,6Z)‐1,4,7‐oxadithiadiononane‐5,6‐dionedioxime (1) and trithia (2Z,3Z)‐1,4,7‐trithionane‐2,3‐dionedioxime (2), respectively. The compounds 5,6,8,9‐tetrahydro [1,4,7]oxadithionine[5,6‐c][1,2,5]oxadiazole (3) and 5,6,8,9‐tetrahydro[1,4,7]trithionino[2,3‐c][1,2,5]oxadiazole (4) were prepared by dehydration of 1 and 2 in aqueous solution of potassium hydroxide at 170–180°C, respectively. 相似文献
127.
Bijan Nekoueishahraki Dipl.‐Chem. Sankaranarayana Pillai Sarish Dipl.‐Chem. Herbert W. Roesky Prof. Dr. Daniel Stern Carola Schulzke Prof. Dr. Dietmar Stalke Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(25):4517-4520
Bi? O chemistry : A direct regioselective route to bismuth bis(amino)naphthalene compounds, incorporating Bi? O and Bi? C bonds is described, in which an amide precursor is treated with aldehydes, ketones, alkenes, and alkynes, leading to insertion into the Bi? NMe2 bond.
128.
129.
Bijan Saha 《Central European Journal of Physics》2010,8(6):920-923
Different characteristics of matter influencing the evolution of the uUniverse haves been simulated by means of a nonlinear
spinor field. We have considered two cases where the spinor field nonlinearity occurs either as a result of self-action or
due to the interaction with a scalar field. 相似文献
130.
Bijan Taeri 《Journal of Applied Mathematics and Computing》2006,20(1-2):75-96
Letm, n be positive integers. We denote byR(m, n) (respectivelyP(m, n)) the class of all groupsG such that, for everyn subsetsX 1, X2, . . .,X n of sizem ofG there exits a non-identity permutation σ such that $X_1 X_2 ...X_n \cap X_{\sigma (1)} X_{\sigma (2)} ...X_{\sigma (n)} \ne \not 0$ (respectively X1X2 . . .X n = Xσ(1)X{σ(2)} . . . X{gs(n)}). Let G be a non-abelian group. In this paper we prove that
- G ∈ P(2,3) if and only ifG isomorphic to S3, whereS n is the symmetric group onn letters.
- G ∈ R(2, 2) if and only if¦G¦ ≤ 8.
- IfG is finite, thenG ∈ R(3, 2) if and only if¦G¦ ≤ 14 orG is isomorphic to one of the following: SmallGroup(16,i), i ∈ {3, 4, 6, 11, 12, 13}, SmallGroup(32,49), SmallGroup(32, 50), where SmallGroup(m, n) is the nth group of orderm in the GAP [13] library.