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21.
Pradeep R. Varadwaj Arpita Varadwaj Helder M. Marques Koichi Yamashita 《Molecules (Basel, Switzerland)》2022,27(5)
The phosphorus bond in chemical systems, which is an inter- or intramolecular noncovalent interaction, occurs when there is evidence of a net attractive interaction between an electrophilic region associated with a covalently or coordinately bonded phosphorus atom in a molecular entity and a nucleophile in another, or the same, molecular entity. It is the second member of the family of pnictogen bonds, formed by the second member of the pnictogen family of the periodic table. In this overview, we provide the reader with a snapshot of the nature, and possible occurrences, of phosphorus-centered pnictogen bonding in illustrative chemical crystal systems drawn from the ICSD (Inorganic Crystal Structure Database) and CSD (Cambridge Structural Database) databases, some of which date back to the latter part of the last century. The illustrative systems discussed are expected to assist as a guide to researchers in rationalizing phosphorus-centered pnictogen bonding in the rational design of molecular complexes, crystals, and materials and their subsequent characterization. 相似文献
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We present an analytical proof of the existence of unidirectional optical Bloch oscillations in a waveguide array system. It is shown that the presence of nonreciprocity in the system allows for a complete normal-mode dephasing in one of the propagation directions, resulting in a unidirectional breakdown in Bloch oscillations. A model system consisting of an array of transversely magnetized asymmetric Si/SiO2 waveguides with a magneto-optic cover layer is presented. Large index contrasts between film and cover are critical for practical realizations. 相似文献
24.
Pandey A. Khan F. A. Kelkar A. Purohit P. Kumar Pradeep Sathe D. B. Bhatt R. B. Behere P. G. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(2):731-740
Journal of Radioanalytical and Nuclear Chemistry - 149Tb, 152Tb, 155Tb and 161Tb can cover all the modalities of diagnostic and therapeutic purposes of nuclear medicine. The production cross... 相似文献
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A wide variety of [1,2,3]triazolo[5,1-c][1,4]benzoxazines were synthesized through palladium-copper catalyzed reactions of 1-azido-2-(prop-2-ynyloxy)benzene with aryl/vinyl iodides. A plausible reaction mechanism has also been proposed. 相似文献
27.
Han X Critchley K Zhang L Pradeep SN Bushby RJ Evans SD 《Langmuir : the ACS journal of surfaces and colloids》2007,23(3):1354-1358
We introduce a new method for forming tethered bilayer lipid membranes on surfaces patterned using a photocleavable self-assembled monolayer (SAM). A SAM terminated with a hydrophobic fluorocarbon residue was bound to a gold surface through a link containing a photocleavable ortho-nitrobenzyl moiety. Hydrophilic regions were produced by irradiation with soft UV (365 nm) through a photomask. The patterned surface was characterized by scanning electron microscopy and electrochemical impedance spectroscopy. Tethered bilayer lipid membranes with well-defined bilayer and monolayer regions were then formed by exposure to egg PC vesicles. The membranes had resistance and capacitance values of 0.52 MOmega.cm2 and 0.83 microF.cm-2, respectively. 相似文献
28.
Ranjan K. Mohapatra Pradeep K. Das Manoj K. Pradhan Abdussalam A. Maihub Marei M. El-ajaily 《Journal of the Iranian Chemical Society》2018,15(10):2193-2227
Schiff bases are stable imines containing C=N, where N is bonded to an alkyl or aryl group, but not with hydrogen and are prepared by condensation of aliphatic or aromatic primary amine with carbonyl compounds. They have the general formula R1R2C?=?NR3, where R3?≠?H. The presence of the basic donor N atom and the stability of the imine function render Schiff bases as the most favored ligands that have the ability to stabilize metal ions in different oxidation states. The chelating environment in a Schiff base profoundly influences the electron distribution in the coordination sphere of metal in a complex and thereby regulates the property of the compounds in a big way. The structural diversity in some of the metal complexes with multidentate Schiff base ligands has triggered a wide range of applications of this class of compounds in sensors, catalysis, biology, medicines, and photonics. This review compiles the synthesis and biological activities (antimicrobial, antioxidant, anticancer, antitubercular, DNA interaction studies) of benzaldehyde-based Schiff bases and their metal complexes. 相似文献
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Structural Chemistry - It is reported that NAMI-A and other Ru-anticancer complexes preferably bind with the N7 site of guanine and can also form DNA inter-strand cross-links. Therefore, in order... 相似文献
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Pradeep Mathur Bala Manimaran Md. Munkir Hossain Arnold L. Rheingold Louise M. Liable-Sands Glenn P.A. Yap 《Journal of organometallic chemistry》1997,540(1-2):165-168
The tris-methylene bridged compound (NO)4Fe2Se(μ-CH2)3 has been isolated. It has been characterised by IR and 1H, 13C, and 77Se NMR spectroscopy. Its structure has been determined by single-crystal X-ray diffraction methods. The structure consists of a heavy atom triangle consisting of one Se and two Fe atoms. The Fe-Fe and the two Fe-Se edges are bridged by methylene groups. 相似文献