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131.
Syed Arshad Hussain 《Journal of Physics and Chemistry of Solids》2010,71(3):323-9718
In this paper we report the reaction kinetics of nanodimensional clay saponite and hectorite with an amphiphilic cation octadecyl rhodamine B (RhB) in hybrid Langmuir monolayer at the air-aqueous clay dispersion interface. The surface pressure-molecular area (π-A) isotherms were strongly influenced by the presence of clay and the lift-off area of the cationic amphiphile shifted to progressively larger area. In-situ fluorescence imaging microscopic (FIM) studies showed the formation of micro-order domains in the organo-clay hybrid monolayer films at the air-clay dispersion interface. In-situ infrared reflection-absorption spectroscopy (IRRAS) was used to demonstrate the reaction kinetics. The time taken to complete the reaction kinetics for RhB-hectorite hybrid films is larger than for RhB-saponite hybrid films. Atomic force microscopic images of hybrid Langmuir-Blodgett films gave compelling visual evidence of the incorporation of clay platelets into the hybrid films, whose density increased with the progress of reaction kinetics. 相似文献
132.
133.
Zhang Xuan-Jun Wu Jie-Ying Zhang Ming-Liang Tian Yu-Peng Jiang Min-Hua Usman Anwar Chantrapromma Suchada Fun Hoong-Kun 《Transition Metal Chemistry》2003,28(6):707-711
Two coordination polymers [Zn(Cabo)2(EtOH)2(4,4-Bipy)]
n
(1), and [Zn2(Cabo)2(NO3)2(4,4-Bipy)2]
n
(2) (Cabo = carbazolylacetate, 4,4-Bipy = 4,4-bipyridine) with chain and ladder structures, respectively, were prepared and characterized by X-ray single-crystal structural analysis. The results showed that the different anions of metal salts have a large effect on the construction of coordination frameworks. Both complexes show strong emissions in the solid state as well as high thermal stability. 相似文献
134.
S. Arshad Jamal Samina Qureshi Samina Noor Ali M. Iqbal Choudhary Atta-Ur-Rahman 《Chemistry of Heterocyclic Compounds》1995,31(9):1047-1059
Four bioactive withanolides withalactone (1), withaoxylactone (2), quresimine-A (4-hydroxy, 3-methoxy-5, 6-epoxy-(22R)-witha-24-enolide) (3) and quresindne-B (4, 27 dihydroxy-3-methoxy-5, 6-epoxy-(22R)-witha-24-enolide (4) have been isolated from the herbs of Withania somnifera, Dunal (Solanaceae). The elucidation of their structures is based on extensive spectroscopic studies, such as1H-NMR, COSY-45°, HMBC, HMQC HOHAHA, E.I., FAB (+ ve), and HR MS, etc.Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1200–1213, September, 1995. 相似文献
135.
Anwar Usman Ibrahim Abdul Razak Hoong‐Kun Fun Suchada Chantrapromma Yan Zhang Jian‐Hua Xu 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):o543-o544
In the title compound, C24H17NO2S, the dioxine and thiazoline rings are distorted from planarity towards a half‐chair and an envelope conformation, respectively. The configurations of the dioxine ring, the thiazoline ring and the attached phenyl ring are conditioned by the sp3 state of the two bridgehead C atoms. The phenanthrene system is nearly coplanar with the dioxine ring, while the attached phenyl ring is orthogonal to the thiazoline ring. 相似文献
136.
Anwar Usman Suchada Chantrapromma Hoong‐Kun Fun Bo‐Long Poh Chatchanok Karalai 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):o46-o47
In the title complex, the 1:1 ionic adduct of hexamethylenetetraminium and 2,4,6‐trinitrophenolate, C6H13N4+·C6H2N3O7?, the cation acts as a donor for bifurcated hydrogen bonds to the O atoms of the phenolate and one of the nitro groups of the 2,4,6‐trinitrophenolate anion. The crystal structure is built from sheets of cations and anions, and is stabilized by intermolecular C—H?O and C—H?π interactions. 相似文献
137.
Suchada Chantrapromma Anwar Usman Hoong‐Kun Fun Bo‐Long Poh Chatchanok Karalai 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):o589-o590
In the title ternary complex, C10H9N2+·C7H3N2O6?·C7H4N2O6, the pyridinium cation adopts the role of the donor in an intermolecular N—H?O hydrogen‐bonding interaction with the carboxylate group of the 3,5‐dinitrobenzoate anion. The molecules of the ternary complex form molecular ribbons perpendicular to the b direction, which are stabilized by one N—H?O, one O—H?O and five C—H?O intermolecular hydrogen bonds. The ribbons are further interconnected by three intermolecular C—H?O hydrogen bonds into a three‐dimensional network. 相似文献
138.
Jia‐Xiang Yang Ze Zhang Jie‐Ying Wu Yu‐Peng Tian Qing‐Liang Liu Hoong Kun Fun Anwar Usman Zbi‐Qiang Xu K. Thompson Laurence 《中国化学》2003,21(11):1461-1465
The synthesis and characterization of the copper (II) complex [Cu2(OOCCH = C(CH3)Fc)3(phen)2]CIO4 · 2H2O (1) are reported. The structure of the complex was determined by single‐crystal X‐ray analysis. The compound crystallizes in the monoclinic system, space group Pc, with Z =2, a = 1.2799(4) nm, b =0.9969 (4) nm, c = 2.5228 nm, and β = 91.576 (1) °. The cationic part of 1 indicates a penametallic core in which three 3‐ferrocenyl‐2‐crotonic acid salt (FCA) groups act as (O, O') bridging ligands between two copper (II) ions with a square‐pyramidal environment. Cyclic voltammetric experiments in acetonitrile have been performed mainly to examine the Fe(II) → Fe(III) one‐electron oxidation in FCA and its complex. The variable‐temperature magnetic susceptibility measurements revealed very weak intramolecular anti‐ferromagnetic coupling. Fitting parameters are 2J = ‐0.2 cm?1, g = 2.114, and θ = 0K. 相似文献
139.
Akbar Azam Muhammad Arshad Ismat Beg 《Rendiconti del Circolo Matematico di Palermo》2008,57(3):433-441
We prove the existence of points of coincidence and common fixed points of a pair of self-mappings satisfying a generalized
contractive condition in cone metric spaces. Our results generalize several well-known recent and classical results.
相似文献
140.
Muhammad?I.?SalehEmail author E.?Kusrini R.?Adnan Ismail?A.?Rahman B.?Saad A.?Usman H.?-K.?Fun B.?M.?Yamin 《Journal of chemical crystallography》2005,35(6):469-475
[Bis-picrate(pentaethylene glycol)]praseodymium(III) picrate, [Pr(pic)2⋅(EO5]+[pic]−, was successfully obtained from the reaction of praseodymium nitrate hexahydrate, picric acid and pentaethylene glycol in acetonitrile–methanol as solvent. The crystal system is monoclinic with space group P21/c, a = 18.91419(11) Å, b = 9.0470(6) Å, c = 24.1209(14) Å and α = γ = 90∘, β = 109.07(1)∘, V = 3880.3(4) Å3 and Z = 4. The Pr atom is coordinated to the flexible and open EO5 ring via all the six oxygen atoms and two picrate ligands, one via phenoxo oxygen atom and the other one with both phenoxo and nitro oxygen atoms in a bidentate manner resulting a 9-coordinate tricapped trigonal prismatic geometry. The two picrate ligands coordinated to the Pr atom are at the opposite sides of the hexadentate EO5 ring with phenyl fragments almost perpendicular with dihedral angle of 89.7(3)∘. Thermal analysis results show that the complex is stable up to 100∘C when it began to slowly decompose and followed by an explosive decomposition at 290∘C. 相似文献