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1.
The concept of the Moore-Penrose inverse in an indefinite inner product space is introduced. Extensions of some of the formulae in the Euclidean space to an indefinite inner product space are studied. In particular range-hermitianness in completely characterized. Equivalence of a weighted generalized inverse and the Moore-Penrose inverse is proved. Finally, methods of computing the Moore-Penrose inverse are presented. 相似文献
2.
Electrically conducting poly(3,4‐ethylenedioxythiophene) (PEDOT) film doped with silicomolybdate (SiMo12O404? or SiMo12) was synthesized by electrochemical polymerization. The synthesized film is capable of fast charge propagation during redox reactions in strong acid medium 0.2 M H2SO4 solution. The modified electrode was used towards reduction of bromate and successfully employed as an amperometric sensor for bromate and also above modified electrode was investigated for ascorbic acid oxidation. 相似文献
3.
Balamurugan S Ista LK Yan J López GP Fick J Himmelhaus M Grunze M 《Journal of the American Chemical Society》2005,127(42):14548-14549
Surface-grafted, environmentally responsive polymers have shown great promise for controlling adsorption and desorption of macromolecules and cells on solid surfaces. In the paper, we demonstrate that certain mixed self-assembled monolayers (SAMs) of oligo(ethylene glycol) (OEG) and methyl-terminated alkanethiolates on gold form surfaces with switchable hydrophobicity and tendency for protein adsorption and cellular attachment. At temperatures above 32 degrees C, SAMs with a surface density of approximately 50% OEG adsorbed significant amounts of pyruvate kinase and lysozyme, whereas below this temperature, these same SAMs were resistant to the adsorption of these proteins. Furthermore, protein layers adsorbed to these SAMs above 32 degrees C were removed upon rinsing with water below this temperature. Similar results were seen for attachment and release of the marine bacterium, Cobetia marina. The change from nonresistance to adsorptive state of the SAMs was concomitant with a change in advancing water contact angle. Vibrational sum frequency generation spectroscopy suggests that the temperature-induced changes coincide with a disorder-to-partial order transition of the hydrated methylene chains of the OEG moieties within the SAMs. Mixed OEG-methyl SAMs represent both a convenient means of controlling macromolecular and cellular adsorption within the laboratory and a useful tool for relating adsorption properties to molecular structures within the SAMs. 相似文献
4.
Balamurugan V Hundal MS Mukherjee R 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(7):1683-1690
Using a group of six neutral M(II)Cl(2)-containing coordination compounds as building blocks, the first systematic investigation of C-H...Cl hydrogen-bonding interactions was performed. Single-crystal X-ray structural analyses of four new compounds (pseudo-tetrahedral Co(II) and Zn(II); distorted trigonal bipyramidal Zn(II)) authenticate the metal coordination geometry. To provide a unified view of the presence of noncovalent interactions in this class of compounds, we have re-examined the packing diagram of two previously reported compounds (a distorted square-pyramidal Cu(II) complex and a trans-octahedral Co(II) complex). The organic ligands of our choice comprise bidentate/tridentate pyrazolylmethylpyridines and an unsymmetrical tridentate pyridylalkylamine. This systematic investigation has allowed us to demonstrate the existence of versatile C-H...Cl(2)M interactions and to report the successful application of such units as inorganic supramolecular synthons. Additional noncovalent interactions such as C-H...O and O-H...Cl hydrogen bonding and pi-pi stacking interactions have also been identified. Formation of novel supramolecular architectures has been revealed: 2D lamellar (p-cyclophane) and 3D lamellar, 3D "stitched staircase" (due to additional hydrogen-bonding interactions by water tetramers, with an average O-O bond length in the tetramer unit of 2.926 A, acting as "molecular clips" between staircases), 3D linked ladder, and single-stranded 1D helix. 相似文献
5.
Ab initio MO and experimental pi-selectivities of hydride additions to 4-oxatricyclo[5.2.1.0(2,6)]decan-10-one and 4-oxatricyclo[5.2.1.0(2,6)]dec-8-en-10-one are described. The interactions of sigma(C1-C2) and sigma(C6-C7) with pi(C=O), on one hand, and those of sigma(C1-C9) and sigma(C7-C8) with pi(C=O), on the other hand, support anti-selectivities for both. This is in full accordance with the experiments. The arguments that are based on electrostatic interactions and electron donation from the ring oxygen do not apply. 相似文献
6.
V. Balamurugan Jhumpa Mukherjee Maninder Singh Hundal Rabindranath Mukherjee 《Structural chemistry》2007,18(2):133-144
New MnII/CuII/ZnII complexes [(L1)MnCl2] (1), [(L2)CuCl2]·0.5H2O (2) and [(L2)ZnCl(H2O)][ClO4] (3), containing (2-pyridyl)alkylamine ligands, N-methyl-N,N-bis(2-pyridylmethyl)amine (L1) and methyl[2-(2-pyridyl)ethyl](2-pyridylmethyl)amine (L2), have been prepared and characterized, including X-ray crystallography. The most striking feature of the structures of these
complexes is the formation of molecular ladder and lamellar topology through the crystal packing arrangement, determined by
both strong O–H···Cl and weak (however, multiple) C–H···Cl hydrogen-bonding interactions, to maintain the neutral/cationic
metal-ligand coordination units linked to each other. In 3, additional secondary interactions are observed involving coordinated solvent and the counter-ion. The results presented
here demonstrate that (i) the choice of organic ligands to provide flexibility and inherent potential to participate in hydrogen-bonding
interactions, (ii) the coordination geometry preferences of metal ions, (iii) the number of metal-bound chloride ion and (iv)
the presence of solvent/counter-anion have a great influence on supramolecular network topology. 相似文献
7.
Gunasekaran Balamurugan Sundarraman Balaji Rengan Ramesh Nattamai S.P. Bhuvanesh 《应用有机金属化学》2019,33(1)
A panel of six new arene Ru (II)‐NHC complexes 2a‐f , (NHC = 1,3‐diethyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1a , 1,3‐dicyclohexylmethyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1b and 1,3‐dibenzyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1c ) were synthesized from the transmetallation reaction of Ag‐NHC with [(η6‐arene)RuCl2]2 and characterized. The ruthenium (II)‐NHC complexes 2a‐f were developed as effective catalysts for α‐alkylation of ketones and synthesis of bioactive quinoline using primary/amino alcohols as coupling partners respectively. The reactions were performed with 0.5 mol% catalyst load in 8 h under aerobic condition and the maximum yield was up to 96%. Besides, the different alkyl wingtips on NHC and arene moieties were studied to differentiate the catalytic robustness of the complexes in the transformations. 相似文献
8.
K. Alagumalai R. Shanmugam T.-W. Chen S.-M. Chen M. Balamurugan S.S. Choi M.A. Ali A.M. Al-Mohaimeed C.-H. Fan 《Materials Today Chemistry》2022
In this work, we developed a perovskite structured samarium cobalt oxide nanoparticles (SmCoO3 NPs) with the aid of the co-precipitation method. The rare earth metal (Sm) and cobalt oxide combined to form a perovskite lattice structure. One-pot route synthesized SmCoO3 NPs were scrutinized successfully through various physicochemical techniques. Concerning its effective thermal stability and electrical properties, the synthesized SmCoO3 NPs have been effectively implemented in the electrochemical evaluation of promethazine hydrochloride (PHY) using cyclic voltammetry. The electrochemical detection of PHY was performed through SmCoO3 NPs-modified glassy carbon electrode (GCE) and unmodified GCE. The electron transfer kinetics, effect of scan rate, the influence of pH, electroactive surface area, selectivity, and sensitivity have been studied. The electron charge transfer rate (Rct) and electrolyte resistance (Rs) were calculated to be 105.59 (Ω) and 150 (Ω) in the ferricyanide probe, indicating great facilitation of the electron transfer between PHY and SmCoO3 NPs deposited on the electrode surface. Further, the optimized SmCoO3-modified GCE exemplifies excellent selectivity, storage stability, reproducibility, repeatability, detection limit (5 nM), sensitivity (0.594 μA μM?1 cm?2), and wide consecutive linear ranges, respectively. Besides, the proposed method has been effectively employed for the detection of PHY in the various real samples which reveals good recoveries of 95.40–99.17%. 相似文献
9.
R. Shanmugam J. Ganesamurthi T.-W. Chen S.-M. Chen M. Balamurugan M.A. Ali A.M. Al-Mohaimeed W.A. Al-onazi K. Alagumalai 《Materials Today Chemistry》2022
Herein, we reported the fabrication of porous iron oxide/carbon black (P–Fe2O3/CB) composite through a two-step engineering method. At first, Prussian blue microcubes were used as a precursor and further calcined to form P–Fe2O3 microcubes. The intercalation of CB nanoparticles with P–Fe2O3 nanocubes was processed through the ultrasonication method. The obtained P–Fe2O3/CB were successfully scrutinized through various physiochemical characterization methods. The proposed P–Fe2O3/CB-modified glassy carbon electrode sensor was successfully implemented in the electrochemical sensing of chlorpromazine hydrochloride due to its very low charge transfer resistance (Rct) compared to the other electrode modifiers. The sensitive detection of CPMH through differential pulse voltammetry exemplifies an excellent electroanalytical performance such as a wide linear range of 0.5–1472 μM, a lower detection limit (0.001 μM), and an appraisable sensitivity of 1.99 μA/μM cm?2 due to its availability of a high number of active sites and its large surface area, respectively. It also expresses excellent selectivity, repeatability, reproducibility, and stability results. Moreover, the practical feasibility of the as-fabricated P–Fe2O3/CB/glassy carbon electrode sensor shows exquisite recovery (98.1–100.8%) results with an appraisable current response in various biological, pharmaceutical, and environmental samples. 相似文献
10.
Udhaya Kumar S. Srivarshini Sankar Salma Younes Thirumal Kumar D. Muneera Naseer Ahmad Sarah Samer Okashah Balu Kamaraj Abeer Mohammed Al-Subaie George Priya Doss C. Hatem Zayed 《Molecules (Basel, Switzerland)》2020,25(23)
Filamins (FLN) are a family of actin-binding proteins involved in regulating the cytoskeleton and signaling phenomenon by developing a network with F-actin and FLN-binding partners. The FLN family comprises three conserved isoforms in mammals: FLNA, FLNB, and FLNC. FLNB is a multidomain monomer protein with domains containing an actin-binding N-terminal domain (ABD 1–242), encompassing two calponin-homology domains (assigned CH1 and CH2). Primary variants in FLNB mostly occur in the domain (CH2) and surrounding the hinge-1 region. The four autosomal dominant disorders that are associated with FLNB variants are Larsen syndrome, atelosteogenesis type I (AOI), atelosteogenesis type III (AOIII), and boomerang dysplasia (BD). Despite the intense clustering of FLNB variants contributing to the LS-AO-BD disorders, the genotype-phenotype correlation is still enigmatic. In silico prediction tools and molecular dynamics simulation (MDS) approaches have offered the potential for variant classification and pathogenicity predictions. We retrieved 285 FLNB missense variants from the UniProt, ClinVar, and HGMD databases in the current study. Of these, five and 39 variants were located in the CH1 and CH2 domains, respectively. These variants were subjected to various pathogenicity and stability prediction tools, evolutionary and conservation analyses, and biophysical and physicochemical properties analyses. Molecular dynamics simulation (MDS) was performed on the three candidate variants in the CH2 domain (W148R, F161C, and L171R) that were predicted to be the most pathogenic. The MDS analysis results showed that these three variants are highly compact compared to the native protein, suggesting that they could affect the protein on the structural and functional levels. The computational approach demonstrates the differences between the FLNB mutants and the wild type in a structural and functional context. Our findings expand our knowledge on the genotype-phenotype correlation in FLNB-related LS-AO-BD disorders on the molecular level, which may pave the way for optimizing drug therapy by integrating precision medicine. 相似文献