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51.
A series of C3-symmetricaltriazine-cored small dendritic molecules containing three to nine peripheral o-carborane clusters were synthesized through Cu(I)-catalyzedazide–alkyne cycloaddition reactions. The newly synthesized molecules containing multiple o-carborane moieties were characterized using nuclear magnetic resonance and matrix-assisted laser desorption/ionization-time of flight mass spectral analysis. The biological evaluation of these three to nine cage dendrimers was performed using breast cancer cells (Michigan Cancer Foundation 7). All these dendritic compounds showed cytotoxicity toward breast cancer cells, and the toxicity increased as the number of peripheral o-carboranes increased. The 9-cage molecule showed the highest cytotoxicity, and the half maximal inhibitory concentration (IC50) value was found to be 80.67 ng/ml. Its cytotoxicity was significantly higher than the common chemotherapy agent cisplatin. As expected, the boron-richo-carborane-appended molecules showed high thermal stability. The thermal stability increased as the number of peripheral o-carborane moieties increased.  相似文献   
52.
We have demonstrated that the intramolecular charge transfer (ICT) probe Methyl ester of N,N-dimethylamino naphthyl acrylic acid (MDMANA) serves as an efficient reporter of the proteinous microenvironment of Human Serum Albumin (HSA). This work reports the binding phenomenon of MDMANA with HSA and spectral modulation thereupon. The extent of binding and free energy change for complexation reaction along with efficient fluorescence resonance energy transfer from Trp-214 of HSA to MDMANA indicates strong binding between probe and protein. Fluorescence anisotropy, red edge excitation shift, acrylamide quenching and time resolved measurements corroborate the binding nature of the probe with protein and predicts that the probe molecule is located at the hydrophobic site of the protein HSA. Due to the strong binding ability of MDMANA with HSA, it is successfully utilized for the study of stabilizing action of anionic surfactant Sodium Dodecyl Sulphate to the unfolding and folding of protein with denaturant urea in concentration range 1M to 9M.  相似文献   
53.
Lipase was immobilized in silk fibers through glutaraldehyde cross-linking to a maximum loading of 59 U/g silk-fiber and the immobilized lipase was utilized for the hydrolysis of sunflower oil (Helianthus annuus). The hydrolytic activity of the lipase, which was poor in biphasic oil in water system, was increased significantly when the sunflower oil was emulsified in aqueous medium. The hydrolytic activities of the immobilized lipase were 48.73 ± 1.26 U, 36.11 ± 0.96 U, and nil when the substrate sunflower oil was used as emulsion created by a rhamnolipid biosurfactant, Triton X100, and ultrasonication, respectively. Although the efficiency of the immobilized lipase was less than 12% than the corresponding free lipase, the immobilized lipase could be reused for the biosurfactant-mediated hydrolysis of sunflower oil up to third cycle of the reaction. The yield of the fatty acids in the second, third, and fourth cycles were 49.45%, 22.91%, and 5.09%, respectively, of the yield obtained in the first cycle.  相似文献   
54.
In conformity with ideas of the recent dualistic approach to gravitation of the author classical heuristic models of nucleons and electrons are constructed. The numerical values computed for the different parameters turn out to be realistic although because of their static character the models as such cannot quite represent reality.  相似文献   
55.
56.
In this article we introduce the vector valued sequence space m(E_k,φ,∧),associated with themultiplier sequence ∧=(λ_k) of non-zero complex numbers,and the terms of the sequence are chosen from theseminormed spaces E_k,seminormed by f_k for all k∈N.This generalizes the sequence space m(φ) introducedand studied by Sargent.We study some of its properties like solidity,completeness,and obtain some inclusionresults.We also characterize the multiplier problem and obtain the corresponding spaces dual to m(E_k,φ,∧).We prove some general results too.  相似文献   
57.
A coupled system of field equations representing interacting gravitational, electromagnetic and pseudoscalar fields is obtained using the five-dimensional formalism of Einstein and Mayer (1931–1932). Solutions of the system for concrete cases are under investigation.  相似文献   
58.
S Bose  PL Knight  MB Plenio  V Vedral 《Pramana》2001,56(2-3):383-391
We present a rare example of a decay mechanism playing a constructive role in quantum information processing. We show how the state of an atom trapped in a cavity can be teleported to a second atom trapped in a distant cavity by the joint detection of photon leakage from the cavities. The scheme, which is probabilistic, requires only a single three level atom in a cavity. We also show how this scheme can be modified to a teleportation with insurance.  相似文献   
59.
Herein, we report the synthesis of tiny spherical Pd nanoparticles (NPs) by green chemical method under ambient conditions using flower extract of Lantana camara plant. The size of the Pd NPs is tunable from 4.7 to 6.3 nm by systematically controlling the concentration of either metal ions or plant extract. The synthesized Pd NPs were well characterized by different spectroscopic, microscopic and diffractometric techniques. The Pd NPs offered good size‐dependent catalytic activity in the Suzuki‐Miyaura C‐C coupling reaction under mild reaction conditions in (1: 1) water‐ethanol mixture. The catalyst is stable and exhibited excellent reusability up to three cycles of coupling reaction after which the catalytic activity decreases.  相似文献   
60.
Journal of Thermal Analysis and Calorimetry - The present work is to study the effect of pressure on the gasification of sugarcane bagasse in a pressurized circulating fluidized bed reactor. The...  相似文献   
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