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261.
B. Z. Belashev M. K. Suleymanov S. Vokál J. Vrláková M. Ajaz Ali Zaman K. H. Khan Z. Wazir 《中国物理 C》2011,35(12):1095-1099
The pseudorapidity spectra of fast particles (with β > 0.7 ) produced in Au (at 11.6 A GeV) and Pb (at 158 A GeV) induced collisions with emulsion (Em) nuclei contain some visual plateaus and shoulders. The plateau is wider for Pb+Em reactions compared with the Au+Em ones. The existence of a plateau is expected for parton models. The Fourier transformation and maximum entropy methods were used to get additional information about the plateaus. The dependence of the plateaus on the centrality of the collisions was also studied using the number of g-particles to fix centrality. It shows that the maximum entropy method could confirm the existence of the plateau and the shoulder on distributions. 相似文献
262.
The nonlinear magnetohydrodynamic (MHD) flow problem with Hall current caused by stretching surface having power law velocity distribution is solved by employing homotopy analysis method (HAM). Perturbation solution of stream function, the expression of skin friction coefficient and graphical results in absence of Hall current (Chiam, Int J Eng Sci 33 (1995), 429) are recovered as the limiting cases. It is found that unlike the solution obtained by Chiam (1995), the present results are valid for weak and large magnetic parameters. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27: 937–959, 2011 相似文献
263.
Verkaar F van der Doelen AA Smits JF Blankesteijn WM Zaman GJ 《Chemistry & biology》2011,18(4):485-494
Wnt/β-catenin signaling plays essential roles in embryonic development, adult stem cell maintenance, and disease. Screening of a small molecule compound library with a β-galactosidase fragment complementation assay measuring β-catenin nuclear entry revealed TAK-715 and AMG-548 as inhibitors of Wnt-3a-stimulated β-catenin signaling. TAK-715 and AMG-548 are inhibitors of p38 mitogen-activated protein kinase, which has been suggested to regulate activation of Wnt/β-catenin signaling. However, two highly selective and equally potent p38 inhibitors, VX-745 and Scio-469, did not inhibit Wnt-3a-stimulated β-catenin signaling. Profiling of TAK-715 and AMG-548 against a panel of over 200 kinases revealed cross-reactivity with casein kinase Iδ and ?, which are known activators of Wnt/β-catenin signaling. Our data demonstrate that this cross-reactivity accounts for the inhibition of β-catenin signaling by TAK-715 and AMG-548 and argue against a role of p38 in Wnt/β-catenin signaling. 相似文献
264.
Zaman S. Zainelabdin A. Amin G. Nur O. Willander M. 《Applied Physics A: Materials Science & Processing》2011,104(4):1203-1209
Hybrid light emitting diodes (LEDs) based on zinc oxide (ZnO) nanorods and polymers (single and blended) were fabricated and
characterized. The ZnO nanorods were grown by the chemical bath deposition method at 50°C. Three different LEDs, with blue
emitting, orange-red emitting or their blended polymer together with ZnO nanorods, were fabricated and studied. The current–voltage
characteristics show good diode behavior with an ideality factor in the range of 2.1 to 2.27 for all three devices. The electroluminescence
spectrum (EL) of the blended device has an emission range from 450 nm to 750 nm, due to the intermixing of the blue emission
generated by poly(9,9-dioctylfluorene) denoted as PFO with orange-red emission produced by poly(2-methoxy-5(20-ethyl-hexyloxy)-1,4-phenylenevinylene)
1,4-phenylenevinylene) symbolized as MEH PPV combined with the deep-band emission (DBE) of the ZnO nanorods, i.e. it covers
the whole visible region and is manifested as white light. The CIE color coordinates showed bluish, orange-red and white emission
from the PFO, MEH PPV and blended LEDs with ZnO nanorods, respectively. These results indicate that the choice of the polymer
with proper concentration is critical to the emitted color in ZnO nanorods/p-organic polymer LEDs and careful design should
be considered to obtain intrinsic white light sources. 相似文献
265.
Muhammad Yousaf Muhammad Pervaiz Muhammad Sagir Ashhar‐uz Zaman Muhammad Mushtaq Muhammad Yasin Naz 《中国化学会会志》2013,60(9):1150-1155
A series of Co(II), Cu(II), Mn(II) and Zn(II) bimetallic complexes have been synthesized with the schiff base ligand 2‐(bis‐2‐hydroxyl phenylidene) diimine (L) derived from the condensation of hydrazine and salicylaldehyde. The synthesized ligand and bimetallic complexes were characterized by different spectroscopic techniques. The characterization of ligand was carried out by FT‐IR, H1NMR, C13NMR and MS while the bimetallic complexes were characterized by FT‐IR and X‐ray crystallographic techniques. The complexes and ligand were employed in vitro for antifungal and antibacterial activities using disc diffusion method. Different fungal strains such as Alternaria Alternate, Aspergillus Flavus and Aspergillus Niger were used to check antifungal activities of bimetallic complexes and ligand. Similarly, the bacterial strains used were Staphylococcus Aureus, Bacillus Subbtilis and Escheria Coli. The biological studies showed that the ligand exhibited lower value of antifungal and antibacterial activities than bimetallic complexes. 相似文献
266.
This article investigates the recent research on a series of anilic acid molecules. The crystallisation of molecules in high symmetry space groups is discussed and rationalised by the arrangement of charge-transfer complexes, which leads to the occurrence of repeated embrace motifs. Since 1997, cyananilic acid (2,5-dicyano-3,6-dihydroxy-1,4-benzoquinone) has been explored due to its valuable physico-chemical features. It is an organic acid that has Mott-insulator properties and organic ferroelectricity. Understanding these properties is an active area of supramolecular chemistry. 相似文献
267.
This is the first in a series of three papers where we study the integral manifolds of the charged three-body problem. The integral manifolds are the fibers of the map of integrals. Their topological type may change at critical values of the map of integrals. Due to the non-compactness of the integral manifolds one has to take into account besides ‘ordinary’ critical points also critical points at infinity. In the present paper we concentrate on ‘ordinary’ critical points and in particular elucidate their connection to central configurations. In a second paper we will study critical points at infinity. The implications for the Hill regions, i.e. the projections of the integral manifolds to configuration space, are the subject of a third paper. 相似文献
268.
Istvan J. Enyedy Jiansuo Wang Wahiduz A. Zaman Kenneth M. Johnson Shaomeng Wang 《ChemInform》2002,33(43):252-252
269.
Drug delivery systems, including liposomes, gels, prodrugs, and so forth, are used to enhance the tissue benefit of a pharmaceutical drug or conventional substance at a specific diseased site with little toxicological impact. Nanotechnology can be a rapidly developing multidisciplinary science that enables the production of polymers at the manometer scale for different medical applications. The use of biopolymers in drug delivery systems provides compatibility, biodegradability and low immunogenicity biologically. Large-scale and smaller-than-expected medication particles can be delivered using biopolymers such as silk fibroins, collagen, gelatine, and others that are easily formed into suspensions. These drug carrier systems are functional at improving drug delivery and can be used in intranasal, transdermal, dental, and ocular delivery systems. This study discusses the latest developments in drug delivery methods based on nanomaterials, mainly using biopolymers like proteins and polysaccharides. 相似文献
270.
Khushbakhat Khan Muhammad Saeed Sameer A. Awad Muhammad Younas Khan Eman M. Khalaf Muhammad Saleh Zaman Vaneeza Aiman Tasmia Irshad Hadia Ahsan 《中国化学会会志》2023,70(1):46-57
The recent study enlightens the synthesis and characterization of zirconia (ZrO2), Fe-doped ZrO2 (Fe@ZrO2), and Ni-doped ZrO2 (Ni@ZrO2) catalysts having new-fangled morphology with tuned band gap as photocatalysts for degradation of textile wastewater dyes methylene blue (MB), malachite green (MG), and their mixtures. SEM imaging of Fe@ZrO2 and Ni@ZrO2 is interestingly varied from ZrO2 as well as doping of transition metals greatly affects the morphology of composites. The optimization study depicts that the pH, time (min) and catalyst amount (g) have a direct relation with degradation efficiency, while the dye concentration (mg/L) has an indirect relation as well. The photocatalytic studies depict that the degradation of MB and MG follows oxidation pathway via hydroxyl radicals (OH•) and holes. Reusability of catalysts corresponds to a little decrease in degradation efficiency in the first two cycles and decreases to about ∼10% (Ni@ZrO2) and ∼12% (Fe@ZrO2) in next three cycles. 相似文献