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71.
Hongxia Liu Libo Li Shaikh Qurat‐ul‐ain Tao Jiang 《Journal of heterocyclic chemistry》2015,52(2):473-477
A series of novel 2,6‐disubstituted purine derivatives were designed and synthesized from 2,6‐dichloropurine. The structures of target compounds were determined by 1H‐NMR, 13C‐NMR, and HRMS. The synthesized compounds were evaluated for their inhibitory activities against lung cancer cell lines of A549 and liver cancer cell lines of Bel‐7402. 2‐(4‐Benzyloxy‐phenylamino)‐6‐(cyclohexylamino)purine( 3 ), 2‐(4‐chloro‐phenylamino)‐6‐(n‐butylamino)purine ( 5 ), 2‐(4‐morpholinoamino)‐6‐(4‐hydroxy‐phenylamino)purine ( 9 ), and 2‐(4‐O‐galactosyl‐phenylamino)‐6‐(cyclohexylamino)purine ( 12 ) exhibited moderate inhibitory activity. 相似文献
72.
Low thresholds for a nonconventional polymer blend—Amplified spontaneous emission and lasing in F81−x:SYx system 下载免费PDF全文
Haider Butt Kamran ul Hasan Jui‐Fen Chang Ayooye Abigael Olawoyin Richard Henry Friend 《Journal of Polymer Science.Polymer Physics》2016,54(1):15-21
A mixture of two polymer materials, poly (9,9‐dioctylfluorene) (F8), and one of the poly(para‐phenylenevinylene) derivatives, superyellow (SY) have been used to make F81?x:SYx polymer blend system. Under a 3–5 ns pulsed‐laser excitation, this system showed excellent optical properties with low threshold values of ≈14 µJ/cm2 and ≈8 µJ/cm2 for amplified spontaneous emission and optically pumped lasing, respectively. The proposed system was also electroluminescent and an interesting candidate for future research on polymer injection lasers. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 15–21 相似文献
73.
This article presents the closed-form solutions of two-sector human capital–based Romer growth model. The partial Hamiltonian approach is effectively applied to some growth models in order to compute the closed-form solutions for economic variables involved in the model. Pontryagin's maximum principle provides the set of first-order system of ODEs, which are regarded as an essential criteria for optimality. The partial Hamiltonian approach is utilized to construct three first integrals of the system using the current value Hamiltonian. With the aid of these first integrals, we computed two distinct exact solutions of Romer model under certain parametric restrictions. The closed-form expressions for control, state, and costate variables are presented explicitly as a function of . We have graphically illustrated the solution curves and observed the effect of human capital parameter on control and state variables. The growth rates of all economic variables are evaluated, and their long-run behavior is predicted. 相似文献
74.
Using kinetic theory approach, the dispersion relation ωr and Landau damping rate γ for dust ion acoustic waves are investigated numerically and analytically in an unmagnetized collisionless dusty plasma considering Cairns distribution for electrons and ions in stationary dust particles background. The phase velocity and Landau damping rate are calculated in the limits vtd∥ < vti∥ << ω/k << vte∥ . The electrons and ions non-thermality effects are incorporated via the non-thermality parameter (0 ≤ α < 1) . The real frequency ωr and Landau damping rate γ of the mode in Cairns bi-Maxwellian distributed plasma are graphically shown to depend on plasma parameters namely non-thermality index α , ion to electron temperature ratio Ti∥/Te∥ and the dust concentration parameter δ (=1 − ηZd) . 相似文献
75.
Muhammad IMRAN Syed Ahtsham ul Haq BOKHARY Ali AHMAD Andrea SEMANIOV-FENOVíKOV 《数学物理学报(B辑英文版)》2013,33(1):187-206
In this paper,we are dealing with the study of the metric dimension of some classes of regular graphs by considering a class of bridgeless cubic graphs called the flower snarks Jn,a class of cubic convex polytopes considering the open problem raised in [M.Imran et al.,families of plane graphs with constant metric dimension,Utilitas Math.,in press] and finally Harary graphs H 5,n by partially answering to an open problem proposed in [I.Javaid et al.,Families of regular graphs with constant metric dimension,Utilitas Math.,2012,88:43-57].We prove that these classes of regular graphs have constant metric dimension. 相似文献
76.
77.
Muhammad Najam‐ul‐Haq Adeela Saeed Fahmida Jabeen Dilshad Hussain Naseem Khan Maryam Shabir Nadeem Raza Muhammad Naeem Ashiq Muhammad Aslam Malana Zafar Iqbal Zafar 《Biomedical chromatography : BMC》2015,29(7):981-989
Determination of the availability of phases for specific separations is an important task achieved by a separation chemist. This becomes vital when the complex samples like biofluids are dealt with in proteome science. The work presented here involves the synthesis and application of terpolymeric sorbent with different functionalizations adopted for the selective enrichment of biomolecules of interest from biological fluids. Synthesis of terpolymer was carried out by the radical polymerization of monomers: methyl acrylate, acrylic acid and vinyl acetate with diethylene glycol dimethacrylate as cross‐linking agent, benzoyl peroxide as initiator and chloroform as a porogenic solvent. Characterization was done through Fourier transform infrared spectroscopy, scanning electron microscopy and nitrogen adsorption porosimetry. The polymer was further modified to immobilized metal ion affinity chromatographic material, with immobilized Fe3+/La3+ ions that allowed phosphopeptide enrichment from tryptic digests of standard proteins as well as milk, egg yolk and human serum. Sensitivity of enrichment down to 50 fmol was achieved in the presence of complex protein background as bovine serum albumin. Hydrophobicity was introduced through octadecyl amine, which provides comparable results to ZipTip C18/C4 for desalting of complex mixtures of all caseins. Analysis of the enriched content was performed by Matrix Assisted Laser Desorption Ionization Mass Spectrometry (MALDI‐MS). Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
78.
S. Kishwar K. ul HasanN.H. Alvi P. KlasonO. Nur M. Willander 《Superlattices and Microstructures》2011
Vertically well aligned zinc oxide nanorods (ZnO NRs) were grown on p-GaN by electrodeposition (ED) and aqueous chemical growth (ACG) techniques and the structures were employed to fabricate white light emitting diodes (LEDs). Room temperature current voltage (I–V), photoluminescence (PL), and electroluminescence (EL) measurements were performed to investigate and compare both LEDs. In general, the I–V characteristics and the PL spectra of both LEDs were rather similar. Nevertheless, the EL of the ED samples showed an extra emission peak shoulder at 730 nm. Moreover, at the same injection current, the EL spectrum of the ED light emitting diode showed a small UV shift of 12 nm and its white peak was found to be broader when compared to the ACG grown LED. The broadening of the EL spectrum of the LED grown by ED is due to the introduction of more radiative deep level defects. The presented LEDs have shown excellent color rendering indexes reaching a value as high as 95. These results indicate that the ZnO nanorods grown by both techniques possess very interesting electrical and optical properties but the ED is found to be faster and more suitable for the fabrication of white LEDs. 相似文献
79.
Marc Vuilhorgne Joëul Malpart Staphane Mutti Serge Mignani 《Journal of heterocyclic chemistry》2003,40(1):159-162
Practical synthesis of 2‐ethoxycarbonylimidazole‐4‐phosphonate ( 1a ) and diethyl imidazole‐2,4‐dicar‐boxylate ( 1b ) are described. 相似文献
80.
Muhammad Salman Sajid Fahmida Jabeen Dilshad Hussain Qurra‐tul‐Ann Afza Gardner Muhammad Naeem Ashiq Muhammad Najam‐ul‐Haq 《Journal of separation science》2020,43(7):1348-1355
Enrichment of glycoproteins has been important because of their dynamicity and role in biological systems. Study of glycoproteins is complex because of the simultaneous glycosylation and deglycosylation inside the body. Often employed affinities for glycopeptides are hydrazide, boronic acid, or physiosorbed lectin on support materials. Cellulose, a natural polysaccharide, has rich surface chemistry, stable structure, low cost and availability in different variants. In present study, fibrous cellulose is oxidized using periodate to modify with boronic acid. Attachment of boronic acid is confirmed by Fourier transform infrared spectroscopy. Particle size and morphology of boronic acid@fibrous cellulose is studied by scanning electron microscopy. The enrichment efficiency is evaluated by using horseradish peroxidase as model protein. Boronic acid@fibrous cellulose is selective up to 1:250 for spiked horseradish peroxidase in bovine serum albumin digest, sensitive down to 0.1 femtomol and recovering 88.15% glycopeptides. Moreover, protein binding capacity is determined as 213 mg/g and 41% sequence coverage of horseradish peroxidase protein with all eight glycosylation sites detected. Total of 18 glycopeptides are enriched from immunoglobulin digest showing ability of boronic acid@fibrous cellulose to enrich glycoproteins from multiglycoforms. Enrichment from human serum recovers 18% extracellular and 72% secreted glycoproteins via bottom‐up approach and online tools. 相似文献