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271.
Inam-ul Bashir 《Journal of Experimental and Theoretical Physics》2017,125(1):65-72
The collision centrality dependence of the yields per unit rapidity dN/dy along with their ratios for various hadrons produced in Au+Au collisions at different collision energies have been studied within the framework of unified statistical thermal freeze-out model (USTFM) taking into account both longitudinal and transverse hydrodynamic flows. Bulk freeze-out properties in terms of the thermal parameters, temperature and mid-rapidity baryon chemical potential at chemical freeze-out, obtained within the proposed model, which are in agreement with experimental data. The extracted chemical freeze-out temperature is found to depend weakly on the collision centrality. It is also found that this temperature is almost independent of the collision energies considered in this work. The closeness of the freeze-out temperature to the predicted phase-transition temperature suggests that the chemical freeze-out happens near hadronization. Furthermore, the dependence of the mid-rapidity chemical potential on the collision energy at different centralities, as well as the centrality dependence of the mid-rapidity size of the system in terms of the transverse size of the system, has been studied at the RHIC. The effect of resonance decay contributions has also been taken into account. 相似文献
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Hana Bashir Shawish Mohammadjavad Paydar Chung Yeng Looi Yi Li Wong Elaheh Movahed Siti Nadiah Abdul Halim Won Fen Wong Mohd-Rais Mustafa Mohd Jamil Maah 《Transition Metal Chemistry》2014,39(1):81-94
Nickel(II) complexes with 2,3-dihydroxybenzaldehyde N4-substituted thiosemicarbazone ligands (H3L1–H3L4) have been synthesized and characterized with the aim of evaluating the effect of N4 substitution in the thiosemicarbazone moiety on their coordination behavior and biological activities. Two series of nickel(II) complexes with the general formulae [Ni(H3L)(H2L)]ClO4 and [Ni2(HL)2] were characterized by analytical and spectral techniques. The molecular structure of one of the complexes, namely, [Ni(H3L4)(H2L4)]ClO4 was established by single crystal X-ray diffraction studies. The crystal structure of this complex revealed that two H3L4 ligands are coordinated to nickel(II) in different modes; one as a neutral tridentate ONS ligand and the other is as a monoanionic tridentate (ONS?) ligand. The antimicrobial activities of the compounds were tested against 25 bacterial strains via the disc diffusion method, and their minimum inhibitory concentration (MIC) and minimum microbicidal concentration were evaluated using microdilution methods. With a few exceptions, most of the compounds exhibited low-to-moderate inhibitory activities against the tested bacterial strains. However, the complexes [Ni2(HL3)2] (7) and [Ni2(HL4)2] (8) indicated higher inhibitory activity against Salmonella enterica ATCC 9068 (MIC values 15.7 and <15.7 μg/ml, respectively), compared with gentamicin as the positive control (MIC 25 μg/ml). Complex (7) also inhibited Streptococcus pneumoniae more efficiently (MIC 31.2 μg/ml), compared with gentamicin (MIC > 50 μg/ml). The toxicities of the compounds were tested on brine shrimp (Artemia salina), where no meaningful toxicity level was noted for both the free ligands and the complexes. The cytotoxicities of the compounds on cell viability were determined on MCF7, PC3, A375, and H413 cancer cells in terms of IC50; complexes [Ni(H3L3)(H2L3)]ClO4 (3), [Ni2(HL3)2] (7) and [Ni2(HL4)2] (8) exhibited significant cytotoxicity on the tested cell lines. 相似文献
275.
Bashir D. Bala Mohamad Kamal A. Rahim Noor Asniza Murad 《Applied Physics A: Materials Science & Processing》2014,117(2):635-639
In this paper, a metamaterial antenna based on complementary electric-LC (CELC) resonator is proposed. The antenna consists of slot-loaded ELC on the ground plane as the main antennas radiating element and excited by a microstrip line. The CELC resonator is characterized by single-negative magnetic moment excited by coupling between the microstrip transmission line and slot-loaded CELC. The peak realized gain and efficiency of 2.63 dB and 86 % are obtained, respectively, at resonance frequency. Simulation and measurement results are presented to validate the design. The antenna is suitable for WLAN applications (2.39–2.48 GHz). 相似文献
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Babar Murtaza Asghar Abbas Aqeel Aslam M. S. Akhtar S. Bashir Mariam Khalid Muhammad Moazzam Naseer 《Research on Chemical Intermediates》2016,42(5):4161-4170
The presently available therapies for type 2 diabetes have not been able to achieve normoglycemic status in a majority of the patients which may be either due to the limitations of the drug itself or its side effects. In an effort to develop potent and safe oral antidiabetic agents, 4-ethyloxychalcone, which was found to be the most potent antiglycating agent in our previous study, has been evaluated for its in vivo hypoglycemic activity using an alloxanized diabetic rat model. The diabetes was induced in rats by injection of intraperitoneal alloxan. However, the oral route was used for the administration of 4-ethyloxychalcone. A significant glucose-lowering effect (P < 0.05) comparable with the standard glibenclamide has been observed for 4-ethyloxychalcone in an oral glucose tolerance test. 4-Ethyloxychalcone also produced a significant decrease (P < 0.05) in fasting blood glucose levels during the 42 days of treatment. Furthermore, a significant lowering (P < 0.05) of glycated hemoglobin (HbA1C ) level was also shown by 4-ethyloxychalcone after 42 days of treatment. Thus, 4-ethyloxychalcone might be regarded as a potential hypoglycemic agent that can act as a platform for the development of future antidiabetic drugs. 相似文献
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Point of present exploration was to figure out the anti corrosion activity of a drug namely Ethambutol on mildsteel in acidic medium as an eco friendly corrosion inhibitor by using weight loss technique, quantum chemical studies and infrared spectral analysis. The results demonstrated that the drug showed highest inhibition efficiency 91.30% at 1000 ppm concentration at 30°C. The increase in temperature lead to decrease in inhibition efficiency and increase in time of immersion lead to increase in inhibition efficiency. 相似文献