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111.
Pradeep Mathur Rajiv Trivedi P. Sekar Debojit Chakrabarty Md. Munkir. Hossain Vedavati G. Puranik 《Journal of Cluster Science》1996,7(2):191-198
The new clusters Fe2
M(CO)10(µ3-S)(µ3-Te), I (M=W) and 2 (M=Mo) have been isolated from the room temperature reaction of Fe2(CO)6(µ-STe) andM(CO)5(THF) (M=W, Mo), respectively. Compounds1 and2 have been characterized by IR, 125 Te NMR spectroscopy, and elemental analysis. The structure of compound1 has been established by X-ray crystallography. It belongs to the triclinic space groupP
witha=6.844(2) Å,b=9.397(2) Å,c=13.681(10) Å, =81.64(2)°,=81360r,=812(2)°,V=861.2(3) Å3,Z=2,D
e
=2.835 g cm–3. Full-matrix least-squares refinement of1 converged to R=0.043, andR
w
.=0.115. The structure consists of a Fe2 WSTe square pyramid and the W atom occupies the apical site of the square pyramid. 相似文献
112.
Seth D Chakraborty A Setua P Chakrabarty D Sarkar N 《The journal of physical chemistry. B》2005,109(24):12080-12085
The energy transfer using 7-amino coumarin dyes as the donor and rhodamine 590 (Rh6G) as the acceptor was investigated in lecithin vesicles and sodium taurocholate (NaTC)-lecithin mixed aggregates using steady-state and time-resolved fluorescence spectroscopy. All energy transfer parameters were calculated. The coumarin 153-Rh6G pair is the most efficient donor-acceptor pair as reflected by the value of k(ET). With addition of NaTC in lecithin, in the case of the coumarin 153-Rh6G pair, the energy transfer rate or efficiency does not change very much, whereas in the case of the coumarin 151-Rh6G pair, the energy transfer rate decreases 2-fold upon going from lecithin vesicles to NaTC-lecithin mixed aggregates where the molar ratio is 2.5. It is mainly due to the deeper location of coumarin 153 in the lipid bilayer or in mixed aggregates. Rotational relaxation data also support this idea. 相似文献
113.
114.
Mathematical Programming - Given a non-negative $$n \times m$$ real matrix A, the matrix scaling problem is to determine if it is possible to scale the rows and columns so that each row and each... 相似文献
115.
Neat formic acid alone efficiently N-formylates carbazoles, 3-alkylindoles, diphenylamine and even moderately weak nucleophilic anilines to furnish the corresponding N-formyl derivatives in 72--87% yields. 相似文献
116.
117.
Venkatraj V. Narayanan R. Srinivasa Gopalan Debojit Chakrabarty Shaikh M. Mobin Pradeep Mathur 《Journal of chemical crystallography》2011,41(6):801-805
Abstract
The title compound, C30H28Cl2N4O6Zn, dichlorobis(ethylanthranilatonicotinamide)zinc(II) crystallized in a triclinic space group, P − 1, with cell parameters a = 7.787(3), b = 13.468(1), c = 15.735(1), α = 110.25(1), β = 95.11(1), γ = 99.32(1) and Z = 2, with the whole molecule being the asymmetric unit. In this compound, zinc is bound to two ethylanthranilatonicotinamide (EAN) ligands and two chloride ligands in a distorted tetrahedral configuration. The nitrogen of the nicotinamide ring participates in bonding with zinc through its lone pair while the anthranilate nitrogen remains free. In one of the two EAN ligands, the anthranilate and nicotinamide groups are nearly co-planar while in the other, the angle between the two is ~35.5°. The complex shows three hydrogen bonds, two being C–H···O bonds and the other being C–H···Cl bond. The amidic N–H groups do not participate in hydrogen bond formation as they are buried in the core structure and are not accessible for other groups for association. Both the C–H···O bonds occur from C–H bonds present on the twisted EAN moiety. 相似文献118.
Saha S Mahato P Reddy G U Suresh E Chakrabarty A Baidya M Ghosh SK Das A 《Inorganic chemistry》2012,51(1):336-345
A new rhodamine-based receptor, derivatized with an additional fluorophore (quinoline), was synthesized for selective recognition of Hg(2+) and Cr(3+) in an acetonitrile/HEPES buffer medium of pH 7.3. This reagent could be used as a dual probe and allowed detection of these two ions by monitoring changes in absorption and the fluorescence spectral pattern. In both instances, the extent of the changes was significant enough to allow visual detection. More importantly, the receptor molecule could be used as an imaging reagent for detection of Hg(2+) and Cr(3+) uptake in live human cancer cells (MCF7) using laser confocal microscopic studies. Unlike Hg(ClO(4))(2) or Hg(NO(3))(2) salts, HgCl(2) or HgI(2) failed to induce any visually detectable change in color or fluorescence upon interaction with L(1) under identical experimental conditions. Presumably, the higher covalent nature of Hg(II) in HgCl(2) or HgI(2) accounts for its lower acidity and its inability to open up the spirolactam ring of the reagent L(1). The issue has been addressed on the basis of the single-crystal X-ray structures of L(1)·HgX(2) (X(-) = Cl(-) or I(-)) and results from other spectral studies. 相似文献
119.
A copper complex having quinoline moiety as fluorophore has been synthesized. The anion recognition behavior of the receptor and its copper complex has been studied in acetonitrile and in acetonitrile: H2O (95:5 v/v). The copper complex shows high selectivity toward acetate over other anions studied such as F−, Cl−, Br−, I−, OAc−, dl-malate, l-mandelate, benzoate, isophthalate, , and . 相似文献
120.
Mallick A Mandal MC Haldar B Chakrabarty A Das P Chattopadhyay N 《Journal of the American Chemical Society》2006,128(10):3126-3127
Tuning of the sensory capability of a potentially bioactive indoloquinolizine system, namely, 3-acetyl-4-oxo-6,7-dihydro-12H-indolo-[2,3-a]-quinolizine (AODIQ), is described in a biomimicking micellar nanocage. It has been shown that surfactant concentration dictates the sensing behavior of the fluorophore toward physiologically essential trace metals, such as Cu2+. This is a simple, efficient, and general technique that allows one to utilize the sensor to its maximum efficiency. 相似文献