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101.
Munazza Raza Mirza Matthias Rainer Shahid Duran Syed Tarique Moin M. Iqbal Choudhary Günther K. Bonn 《Biomedical chromatography : BMC》2019,33(9)
A poly(dibenzo‐18‐crown‐6) was used as a new solid‐phase extraction material for the selective enrichment of phosphopeptides. Isolation of phosphopeptides was achieved based on specific ionic interactions between poly(dibenzo‐18‐crown‐6) and the phosphate group of phosphopeptides. Thus, a method was developed and optimized, including loading, washing and elution steps, for the selective enrichment of phosphopeptides. To assess this potential, tryptic digest of three proteins (α‐ casein, β‐casein and ovalbumin) was applied on poly(dibenzo‐18‐crown‐6). The nonspecific products were removed by centrifugation and washing. The spectrometric analysis was performed using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. Highly selective enrichment of both mono‐ and multiphosphorylated peptides was achieved using poly(dibenzo‐18‐crown‐6) as solid‐phase extraction material with minimum interference from nonspecific compounds. Furthermore, evaluation of the efficiency of the poly(dibenzo‐18‐crown‐6) was performed by applying the digest of egg white. Finally, quantum mechanical calculations were performed to calculate the binding energies to predict the affinity between poly(dibenzo‐18‐crown‐6) and various ligands. The newly identified solid‐phase extraction material was found to be a highly efficient tool for phosphopeptide recovery from tryptic digest of proteins. 相似文献
102.
An efficient synthetic method for the preparation of pyridyl‐pyrimidines as potential inhibitors of protein–protein interactions is described. The key transformation is the reaction of a pyrimidine enaminone with phenyl ethyl acetate and NH4OAc to yield the desired pyridyl‐pyrimidine. 相似文献
103.
104.
Surendra K. Gautam Dhananjai Pandey S.N. Upadhyay Shahid Anwar N.P. Lalla 《Solid State Communications》2008,146(9-10):425-427
The problem of identification of the correct crystalline structure of CdS nanoclusters below 2.5 nm in size is outlined. Structure of thiophenol capped CdS nanoclusters in the size range 1.2–4.3 nm, synthesized using cadmium acetate solution in methanol, is discussed using powder XRD and electron diffraction data. Unambiguous confirmation of the wurtzite phase in CdS nanoclusters below 2.5 nm size is reported. The observation of 102 wurtzite peak in the XRD patterns of such nanoclusters indicates low stacking fault concentration. 相似文献
105.
Lughmani Faiza Nazir Farzana Khan Shahid Ali Iqbal Mudassir 《Cellulose (London, England)》2022,29(3):1911-1928
Cellulose - In this study, microcrystalline cellulose (MCC) was modified to oxidized cellulose (OC), 6-deoxycellulose hydrazide and 6-deoxycellulose (N,N-diethyl)amine (MCC-Hyd and MCC-DEM)... 相似文献
106.
In this work, we report a novel dinuclear Sn (II) complex, [Sn2(Hpdm)2(H2O)6] 2H2O 2Cl ( 1 ) (H2pdm = pyridine‐2,6‐dimethanol), which has been crystallized out and characterized by elemental analysis, FTIR, 1H and 13C NMR, single crystal X‐ray studies and Density Functional Theory (DFT) analysis. X‐ray structure of 1 has confirmed it to be a dinuclear alkoxo‐bridged Sn (II) species where each metal adopts a seven coordinate distorted pentagonal bipyramidal (pbp) geometry. This is the first hepta‐coordinated Sn (II) complex ever isolated apart from already reported stannylenes. Spin density plots from DFT support the +2 oxidation state of each tin metal. Hirshfeld surface analysis reveals the presence of various H‐bonding interactions in the molecule and molecular docking results along with DFT confirm higher binding affinity of the present complex towards DNA. Moreover, the complex exhibits promising anticancer activities against HeLa and A549 cancer cell lines. 相似文献
107.
108.
Nasuha Siti Pershaanaa M. Bashir Shahid Ramesh K. Ramesh S. 《Journal of Solid State Electrochemistry》2022,26(8):1733-1746
Journal of Solid State Electrochemistry - Binary metal sulfide–based electrode materials with distinct nanoarchitecture, improved conductivities, and fascinating mechanical stabilities are... 相似文献
109.
Position-dependent-mass systems are of great importance in many physical situations,such as the transport of charge carriers in semiconductors with non-uniform composition and in the theory of many-body interactions in condensed matter.Here we investigate,numerically and analytically,the phenomenon of fractional revivals in such systems,which is a generic characteristic manifested by the wave-packet evolution in bounded Hamiltonian systems.Identifying the fractional revivals using specific probe... 相似文献
110.
M. Shahid Rafique Shazia Bashir Ali Ajami Wolfgang Husinsky 《Applied Physics A: Materials Science & Processing》2010,100(4):1183-1189
We have investigated femtosecond laser irradiation effects on the surface topography, structural changes and nonlinear absorption
properties of CR-39. For this purpose, a CR-39 target was exposed in air to 25 fs, 800 nm Ti: sapphire laser radiation at
fluences ranging from 0.25 J cm−2 to 3.6 J cm−2. The surface of irradiated CR-39 probed by an Atomic Force Microscope (AFM) exhibits the formation of several topographical
structures, like bumps, explosions and nano cavities. Raman spectroscopy is performed to explore chemical and structural modification
of the irradiated target. The spectroscopy reveals changes such as cross linking, bond breaking, formation of new bonds etc.
in the fundamental structure of the polymer after irradiation. In order to establish a correlation between morphological and
structural changes with the changes in the nonlinear absorption of the irradiated CR-39, a Z-scan technique was employed.
A comparison of experimentally obtained data from Z-scan measurements with our calculations predicts the dominance of three-photon
absorption in the case of pristine CR-39, whereas for irradiated targets concurrence of three- and two-photon absorption is
probable. Nonlinear absorption increases with increasing laser fluences and is well correlated by surface and structural changes
revealed by AFM and Raman spectroscopy. 相似文献