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1.
Absolute total electron scattering cross sections for carbon dioxide have been measured at low electron energies using a photoelectron
source. The measurements have been carried out at 27 electron energies varying from 0.91–9.14 eV with an accuracy of ±3%.
The cross sections obtained in the present experiment have been compared with other measurements and theoretical computations. 相似文献
2.
3.
Kamlakar Avasthi Diwan S. Rawat Tilak Chandra Ashoke Sharon Prakas R. Maulik 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(6):o311-o313
In 5-benzyl-1,7-dimethyl-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-d]pyrimidine-4,6-dione, C14H14N4O2, which crystallizes in space group P, weak intermolecular C—H⋯O hydrogen bonds generate dimers. The isomeric compound 1-benzyl-5,7-dimethyl-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-d]pyrimidine-4,6-dione, C14H14N4O2, crystallizes in space group P21/n, and shows no such dimerization. Instead, it exhibits C—H⋯π interactions with the phenyl ring. In both structures, the molecules are linked by aromatic π–π-stacking interactions. 相似文献
4.
A new chelating resin was synthesised by the modification of styrene-divinylbenzene (2%) copolymer and incorporation of dithiocarbamate groups. The polydithiocarbamate resin was characterised by elemental analysis, thermal studies and IR studies. The analytical characteristics of the sorbent were established and optimum sorption conditions for Cu, Ni, Pb, Fe, As and Mn determined. The total sorption capacity of the resin was 37 mg g−1 for Ni(II), 35 mg g−1 for Cu(II), 29 mg g−1 for Fe(III) and 23 mg g−1 for Pb(II). The optimum pH for the removal of metal ions was 3-5 for Ni(II), 5 for Cu(II), 4 for Fe(III) and 4-5 for Pb(II). High sorption capacity was observed when compared with other conventional chelating polymers. The sorption kinetics was fairly rapid, as apparent from the loading half time t1/2 values, indicating a better accessibility of the chelating sites. 相似文献
5.
Renu Sharma Santosh K. Agarwal Shikha Rawat Meena Nagar 《Transition Metal Chemistry》2006,31(2):201-206
The synthesis and characterization of some transition metal cis-3,7-dimethyl-2,6-octadiensemicarbazone (CDOSC) complexes are reported. The ligand CDOSC yields: [ML2 Cl2] and [ML2 Cl2] Cl type complexes, where M = CrIII, MnII, FeIII, CoII, NiII, CuII, ZnII, CdII and HgII, L = CDOSC. Structures of the complexes were determined using elemental analysis, molar conductivity, magnetic measurements,
i.r. and electronic, as well as n.m.r spectra. CDOSC acts as a bidentate ligand in all the complexes. All the newly synthesized
metal complexes, as well as the ligand, were screened for their antibacterial activity. All the complexes exhibit strong inhibitory
action against Gram (+) bacteria Staphylococcus aureus and Gram (−) bacteria Escherichia coli. The antibacterial activities of the complexes are stronger than those of the ligand CDOSC itself. 相似文献
6.
Abstract A biocompatible zinc (II) complex based on a tetradentate N,N,O,O-type salen ligand was synthesized, characterized and used for the solvent-free ring-opening polymerization (ROP) of L-lactide in bulk at 180?°C to prepare high molecular weight poly(L-lactide) (Mn : 82,600?Da; Mw : 140,000?Da; PDI: 1.70). Poly(L-lactide) (PLLA) was characterized using FTIR, 1H NMR, 13C NMR, GPC, TGA, DSC, WAXD, and MALDI-ToF. Kinetic measurement was carried out and first-order behavior to monomer was observed. The k app was found as 6?±?0.001?×?10?4?s?1. The biocompatibility of the PLLA was confirmed by in vitro cytotoxicity against NIH/3T3 fibroblast cell line and can be used in biomedical applications. 相似文献
7.
Anil M. Shelke Varun Rawat Gurunath Suryavanshi Arumugam Sudalai 《Tetrahedron: Asymmetry》2012,23(22-23):1534-1541
A new enantioselective synthesis of two important fungal metabolites, (+)-stagonolide C and (?)-aspinolide A, has been described from readily available raw materials. Proline catalyzed asymmetric α-aminooxylation and Jorgensen’s epoxidation of aldehydes are the key reactions employed in the introduction of chirality. The formation of the 10-membered lactone core structure was finally accomplished via Steglich esterification and ring closing metathesis reactions. 相似文献
8.
Chen Hui Sharma Sunil K. Sharma Priyanka R. Chi Kai Fung Eric Aubrecht Katherine Keroletswe Ngonye Chigome Samuel Hsiao Benjamin S. 《Cellulose (London, England)》2021,28(13):8611-8628
Cellulose - Mercury contamination in drinking water is a worldwide problem due to its severely harming effects on the human body. A nanostructured natural bioadsorbent, carboxycellulose nanofiber... 相似文献
9.
Mixed Polymer‐Coated Magnetic Nanoparticles as Forward Osmosis Draw Agents of Tuned Hydrophilicity
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Dr. Priyanka Dey Dr. Emad L. Izake 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(32):11253-11260
We recently reported a polymer‐coated magnetic nanoparticle (MNP) draw agent for the forward osmosis (FO) water desalination process. The water flux was found to increase when the polymer poly(sodium acrylate) (PSA) was anchored to the MNP surface as compared to the polymer (or polyelectrolyte solution) alone, due to the polymer chains being stretched out and most of the hydrophilic groups on the polymer contributing to water flux. We herein report the use of a secondary polymer poly(N‐isopropylacrylamide) PNIPAM to manipulate the PSA polymer conformation and influence inter‐ and intrachain interactions to enhance the efficiency of the FO draw agent. These PSA–PNIPAM‐coated MNPs generated a much higher water flux of ~11.66 LMH when compared to the 100 % PSA‐coated MNPs featuring a value of ~5.32 LMH under identical FO conditions. The osmotic pressure and water flux driven by the mixed polymer‐coated MNPs were found to be a strong function of the net polymer coverage on MNPs, that is, net available hydrophilic groups. Our new draw agent demonstrates potential for use in the water industry due to its improved efficiency and cost effectiveness as it uses only ~0.062 % (w/v) of the draw agent solution. 相似文献
10.
Simultaneous quantification of atenolol and chlorthalidone in human plasma by ultra‐performance liquid chromatography–tandem mass spectrometry
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Jaivik V. Shah Daxesh P. Patel Priyanka A. Shah Mallika Sanyal Pranav S. Shrivastav 《Biomedical chromatography : BMC》2016,30(2):208-216
A simple, sensitive and reproducible ultra‐performance liquid chromatography–tandem mass spectrometry method has been developed for the simultaneous determination of atenolol, a β‐adrenergic receptor‐blocker and chlorthalidone, a monosulfonamyl diuretic in human plasma, using atenolol‐d7 and chlorthalidone‐d4 as the internal standards (ISs). Following solid‐phase extraction on Phenomenex Strata‐X cartridges using 100 μL human plasma sample, the analytes and ISs were separated on an Acquity UPLC BEH C18 (50 mm × 2.1 mm, 1.7 µm) column using a mobile phase consisting of 0.1% formic acid–acetonitrile (25:75, v/v). A tandem mass spectrometer equipped with electrospray ionization was used as a detector in the positive ionization mode for both analytes. The linear concentration range was established as 0.50–500 ng/mL for atenolol and 0.25–150 ng/mL for chlorthalidone. Extraction recoveries were within 95–103% and ion suppression/enhancement, expressed as IS‐normalized matrix factors, ranged from 0.95 to 1.06 for both the analytes. Intra‐batch and inter‐batch precision (CV) and accuracy values were 2.37–5.91 and 96.1–103.2%, respectively. Stability of analytes in plasma was evaluated under different conditions, such as bench‐top, freeze–thaw, dry and wet extract and long‐term. The developed method was superior to the existing methods for the simultaneous determination of atenolol and chlorthalidone in human plasma with respect to the sensitivity, chromatographic analysis time and plasma volume for processing. Further, it was successfully applied to support a bioequivalence study of 50 mg atenolol + 12.5 mg chlorthalidone in 28 healthy Indian subjects. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献