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61.
Muhammad Saleem Naseem Akhter Muhammad Shaiq Ali Mamona Nazir Naheed Riaz Muhammad Moazzam Muhammad Arshad Abdul Jabbar 《Magnetic resonance in chemistry : MRC》2009,47(3):263-265
Chromatographic analysis of the alcoholic extract from Salsola imbricata yielded two new secondary metabolites, salisomide (1) and salisoflavan (2). Their structures were established with the help of spectroscopic techniques including COSY, HMQC and HMBC NMR experiments. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
62.
Avcı Davut Altürk Sümeyye Sönmez Fatih Tamer Ömer Başoğlu Adil Atalay Yusuf Zengin Kurt Belma Dege Necmi 《Molecular diversity》2021,25(1):171-189
Molecular Diversity - The World Health Organization (WHO) report shows that diabetes mellitus (DM) will be one of the ten deadly diseases in the near future. The best way to prevent DM is to... 相似文献
63.
S. Ahmad T. Rüffer H. Lang S. Nadeem S. A. Tirmizi M. Saleem A. Anwar 《Russian Journal of Coordination Chemistry》2010,36(7):520-524
The palladium(II) complex, [Pd(PPh3)2(Imt)2]Cl2 · 3.5H2O (I) (Imt = imidazolidine-2-thione), has been synthesized and characterized by IR, NMR, and X-ray crystallography. An upfield
shift in the >C=S resonance of Imt in the 13C NMR spectrum and a downfield shift in the N-H resonance in 1H NMR are consistent with the sulfur coordination of Imt to palladium(II). In the crystal structure of I, the central palladium atom is coordinated to two thione sulfur atoms of Imt and to two phosphorus atoms possessing a square-planar
environment with the average cis and trans bond angles of 89.60° and 167.31°, respectively. The title complex was screened for antimicrobial effects, and the results
showed that it exhibits moderate activities against gram-negative bacteria (E. coli, P. aeruginosa). The complexes also exhibited significant activities against yeast (C. albicans, S. serevisaiae). 相似文献
64.
Phytochemical investigation of the ethyl acetate extract of the leaves of Juniperus procera growing in south Saudi Arabia Enemas region led to the isolation of a new flavonoid using different chromatographic methods (i.e. paper, thin layer and column chromatography). The isolated flavonoid was identified and established by m.p., 1H-NMR, 13C-NMR, UV and MS spectral analysis. The isolated compound was identified as 3′,4′,3,7-tetrahydroxyflavone. 相似文献
65.
Adil Belhaj 《Physics letters. [Part B]》2011,705(5):539-542
Using D-brane physics, we study fractional quantum Hall solitons (FQHS) in ABJM-like theory in terms of type IIA dual geometries. In particular, we discuss a class of Chern-Simons (CS) quivers describing FQHS systems at low energy. These CS quivers come from R-R gauge fields interacting with D6-branes wrapped on 4-cycles, which reside within a blown up CP3 projective space. Based on the CS quiver method and mimicking the construction of del Pezzo surfaces in terms of CP2, we first give a model which corresponds to a single layer model of FQHS system, then we propose a multi-layer system generalizing the doubled CS field theory, which is used in the study of topological defect in graphene. 相似文献
66.
Ndubuisi B. Ukah Satyaprasad P. Senanayak Danish Adil Grant Knotts Jimmy Granstrom K. S. Narayan Suchi Guha 《Journal of Polymer Science.Polymer Physics》2013,51(21):1533-1542
Low‐operating voltage, high mobility, and stable organic field‐effect transistors (OFETs) using polymeric dielectrics such as pristine poly(4‐vinyl phenol) (PVP) and poly(methyl methacrylate) (PMMA), dissolved in solvents of high dipole moment, have been achieved. High dipole moment solvents such as propylene carbonate and dimethyl sulfoxide used for dissolving the polymer dielectric enhance the charge carrier mobilities by three orders of magnitude in pentacene OFETs compared with low dipole moment solvents. Fast switching circuits with patterned gate PVP‐based pentacene OFETs demonstrated a switching frequency of 75 kHz at input voltages of |5 V|. The frequency response of the OFETs is attributed to a high degree of dipolar‐order in dielectric films obtained from high‐polarity solvents and the resulting energetically ordered landscape for transport. Remarkably, these pentacene‐based OFETs exhibited high stability under bias stress and in air with negligible shifts in the threshold voltage. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013 , 51, 1533–1542 相似文献
67.
Mauji Ram Salim Khan Prabhakar Jha Mather A. Khan Usha Kiran Saleem Javed Malik Z. Abdin 《Chromatographia》2008,68(1-2):129-133
A simple, rapid, specific and sensitive thin layer chromatographic (TLC) method has been developed for the quantitative estimation of mevalonic acid (MVA) in leaves of medicinal plants; Artemisia annua, Psorelia corylifolia, Vinca rosea, Withania somnifera and Barleria proinites. The assay procedure involved conversion of MVA to its lactone, mevalonolactone (MVAL). Mevalonic acid was extracted from the leaf tissues of plants. Separation of MVAL was carried out on silica gel 60 F254 TLC plates using benzene:acetone (3:2) as the mobile phase. The densitometric determination of MVAL was performed at 600 nm after derivatization with anisaldehyde reagent in absorption–reflectance mode. The method was validated over the linearity range of 100–500 ng spot?1 and correlation coefficient for the calibration curve was >0.99. The average recovery of MVAL, used as internal standard, was higher than 98%. The lower limit of detection was found to be 50 ng spot?1. 相似文献
68.
Mohammad Saleem 《代数通讯》2013,41(9):3227-3247
69.
Adil Yaqub 《Results in Mathematics》2006,49(3-4):377-386
A well-known theorm of Jacobson asserts that a ring R with the property that for every x in R there exists an integer n(x) > 1 such that xn(x) = x is necessarily commutative. With this as motivation, we define an N0-ring to be a ring which satisfies a weaker hypothesis than the “xn(x) = x” condition in Jacobson’s Theorem. We consider commutativity of N0-rings, usually with the additional hypothesis that the ground ring is also weakly periodic-like. 相似文献
70.
Summary The Korteweg-de Vries equation for ion acoustic waves in the presence of weakly relativistic ion streaming velocity is derived
in a magnetic plasma. It is found that relativistic effects are important in the solitary wave propagation for both fast and
slow modes. Earlier results are reconfirmed.
To speed up publication, the authors of this paper have agreed to not receive the proofs for correction. 相似文献