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排序方式: 共有230条查询结果,搜索用时 15 毫秒
81.
82.
Electrochemical Activation of Graphite Nanosheets Decorated with Palladium Nanoparticles for High Performance Amperometric Hydrazine Sensor 下载免费PDF全文
Chelladurai Karuppiah Murugan Velmurugan Shen‐Ming Chen Rajkumar Devasenathipathy Raj Karthik Sea‐Fue Wang 《Electroanalysis》2016,28(4):808-816
Herein, we have demonstrated a preparation of palladium nanoparticles on electroactivated graphite nanosheets modified screen printed carbon electrode (PdNPs‐EGNS/SPCE) by a simple electrochemical method. The well‐prepared electrocatalyst was potentially applied to the high performance electrocatalytic oxidation of hydrazine in neutral medium. The PdNPs‐EGNS novel composite was characterized by scanning electron microscope (SEM) and the average diameter and thickness of PdNPs and EGNS were found to be ~38 nm and 85 nm, respectively. The high performance electrocatalytic determination of hydrazine was performed by the amperometric i‐t method. The fabricated sensor displayed irreversible electrocatalytic oxidation of hydrazine with diffusion‐controlled electrode process. The oxidation of hydrazine at PdNPs‐EGNS/SPCE showed wider linear range 0.05–1415 µM and high sensitivity 4.382 µA µM?1 cm?2. The as‐prepared electrocatalyst achieved quick response towards hydrazine with a lower detection limit 4 nM. 相似文献
83.
Nivedita Rathnakar Desai Krishnaswamy Gurunathan Parameshwar Adimule Suchetan Aruna Kumar Doyjide Basappa Shivalingegowda Naveen Neratur Krishnappagowda Lokanath Swamy Sreenivasa 《Research on Chemical Intermediates》2017,43(11):6131-6154
The present work reports the synthesis of novel 2-(4-(4-substitutedphenylsulfonyl) piperazin-1-yl) quinolone-3-carbaldehyde derivatives, namely, 2-(4-tosylpiperazin-1-yl)quinoline-3-carbaldehyde (4a), 2-(4-(4-nitrophenylsulfonyl)piperazin-1-yl)quinoline-3-carbaldehyde (4b) and 2-(4-(4-tert-butylphenylsulfonyl) piperazin-1-yl)quinoline-3-carbaldehyde (4c). These compounds have been characterized by FT-IR, 1H-NMR, 13C-NMR and LCMS. Further, the structures of compounds 4b and 4c have been elucidated by single crystal X-ray diffraction studies. The asymmetric unit of 4b contains two molecules (A and B) and that of 4c contains one. The piperazine ring in both the molecules 4b and 4c has chair conformation and the aldehyde group is twisted with respect to the quinoline group, respectively, by 13.3 (3)°, 18.2 (3)° and 11.2 (3)° in Molecule A & B of 4b and 4c due to the bulky piperazinyl group present in the ortho position. The crystal structures of both features interactions of the type C-H…O, C-H…πaryl and πaryl… πaryl, leading to a three-dimensional (3D) supramolecular architecture in 4b and a one-dimensional (1D) architecture in 4c. The various intermolecular interactions exhibited in 4b and 4c are well supported by Hirshfeld surface and fingerprint plots analysis. Further, the three compounds were evaluated for their in-silico antimicrobial activity. In-silico molecular docking studies were carried out in order to know the binding modes of the synthesized compounds with DNA Gyrase A and N-myristoyltranferase as target proteins for antibacterial and antifungal docking studies, respectively. 相似文献
84.
Energy deficit spectra of field ions coming from above a single atomic site are measured by using an atom-probe FIM modified with a Möllenstedt energy analyzer. This device offers a resolution of 5 × 10?5 and is inherently more efficient and less noisy than a retarder. The energy spectra made up of 10 to 100 ions/sec are displayed on the screen of an assembly of two microchannel plates and are photographically recorded within a few seconds. Jason peaks for H2+ and Ne+ are confirmed, and are also found for He+. High-order multiple peaks appear when ions are taken from the flat, closely packed net planes of W and Ir field ion emitters. The results are in quantitative agreement with a resonance model similar to one by Alferieff and Duke and by Jason. Noble gas ions are also observed from the forbidden zone near the surface, and interpreted as apex-adsorbed atoms ionized by or after excitation by the electron shower coming from farther-out field ionization of other gas atoms. Energy from excited metastable apex-adsorbed atoms may account for artifact vacancies observed particularly when field evaporation is performed in neon. 相似文献
85.
86.
P. Hemalatha D. Velmurugan J. Mallika 《Journal of Physics and Chemistry of Solids》2009,70(2):322-1463
X-ray diffraction study of the nonlinear optical (NLO) material S-benzyl isothiouronium chloride (C8H11N2SCl) (SBTC) is reported for the first time. The single crystal of SBTC is orthorhombic with space group Pbca. SBTC exhibits second-order NLO susceptibility, and this study shows that hydrogen bonding is, in part, responsible for this. The present work shows that C-H?Cl and N-H?Cl hydrogen bonds direct the nature of the three-dimensional lattice. Such intermolecular interactions help to extend the molecular charge transfer into the supramolecular realm, the charge transfer originating as a consequence of the high level of molecular planarity and strong donor-to-acceptor interactions. Density functional theory (DFT) calculation and atom-in-molecule (AIM) analysis has been carried out to study the nature of hydrogen involved in the SBTC complex. 相似文献
87.
88.
Ares J. Rosakis Sridhar Krishnaswamy Hareesh V. Tippur 《Optics and Lasers in Engineering》1990,13(3-4):183-210
Several possible sources of inaccuracy that occur in the classical interpretation of caustics patterns generated during transient crack growth in elastic materials are examined using a ‘Bifocal Caustics’ set-up and a new full field optical technique called ‘Coherent Gradient Sensing’. During unsteady dynamic crack growth, strict KdI-dominance is generally absent, especially at times close to crack initiation and arrest, even in regions outside the crack-tip 3-D zone where plane stress conditions persist. In such cases a truly transient higher order expansion is found to be essential for correctly describing stress fields outside the 3-D zone. 相似文献
89.
90.
Summary Heptakis(6-azido-6-deoxy) perphenylcarbamated β-cyclodextrin has been synthesized and chemically immobilized on silica gel
for use as a chiral stationary phase (PC-CSP) for analytical separation of the enantiomers of chiral drugs. Separation of
the enantiomers of tolperisone was studied by high-performance liquid chromatography under reversed-phase conditions. The
chromatographic conditions were optimized by varying mobile phase pH, composition, ionic strength, and velocity; 40:60 methanol-1%
triethylammonium acetate (TEAA) buffer, pH 5.5, was found to be the most suitable for this separation. 相似文献