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101.
102.
An attempt is made to study the existence of dynamical fluctuations of relativistic particles using the methods of modified multifractal moments, Gq, and scaled factorial moments, Fq, in terms of new scaled variable X(η) suggested by Bialas and Gazdzicki. For this purpose analyses of experimental and UrQMD data involving interactions of 28Si and 12C nuclei at with nuclear emulsion are used. The variation of lnGq and lnFq with lnM in pseudorapidity (η) phase space reveals power law behaviour. The values of slopes, τq and q determined from the analyses of Gq and Fq moments are discussed. The generalized fractal dimensions, Dq, determined from the above methods are found to decrease with the order of the moments, q, indicating multifractality in multiparticle production. It is also observed that the spectral function f(αq) for heavier projectile is much broader than for lighter beam due to larger number of participating nucleons present in heavier projectile. 相似文献
103.
Siraj Uddin Luqman Bin Safdar Saeed Anwar Javed Iqbal Sabiha Laila Banzeer Ahsan Abbasi Muhammad Saqib Saif Musrat Ali Abdul Rehman Abdul Basit Yong Wang Umar Masood Quraishi 《Molecules (Basel, Switzerland)》2021,26(6)
Green synthesis of nanomaterials is advancing due to its ease of synthesis, inexpensiveness, nontoxicity and renewability. In the present study, an eco-friendly biogenic method was developed for the green synthesis of nickel oxide nanoparticles (NiONPs) using phytochemically rich Berberis balochistanica stem (BBS) extract. The BBS extract was rich in phenolics, flavonoids and berberine. These phytochemicals successfully reduced and stabilised the NiNO3 (green) into NiONPs (greenish-gray). BBS-NiONPs were confirmed by using UV-visible spectroscopy (peak at 305 nm), X-ray diffraction (size of 31.44 nm), Fourier transform infrared spectroscopy (identified -OH group and Ni-O formation), energy dispersive spectroscopy (showed specified elemental nature) and scanning electron microscopy (showed rhombohedral agglomerated shape). BBS-NiONPs were exposed to multiple in vitro bioactivities to ascertain their beneficial biological applications. They exhibited strong antioxidant activities: total antioxidant capacity (64.77%) and 2, 2-diphenyl-1-picrylhydrazyl (71.48%); and cytotoxic potential: Brine shrimp cytotoxicity assay with IC50 (10.40 µg/mL). BBS-NiONPs restricted the bacterial and fungal pathogenic growths at 1000, 500 and 100 µg/mL. Additionally, BBS-NiONPs showed stimulatory efficacy by enhancing seed germination rate and seedling growth at 31.25 and 62.5 µg/mL. In aggregate, BBS extract has a potent antioxidant activity which makes the green biosynthesis of NiONPs easy, economical and safe. The biochemical potential of BBS-NiONPs can be useful in various biomedical and agricultural fields. 相似文献
104.
The present paper examines the hydromagnetic three-dimensional flow induced by a stretched surface. An incompressible material saturates the porous medium. Velocity and thermal slip boundary conditions are considered. Suitable transformations are used to obtain the nonlinear ordinary differential equations. Series solutions of the resulting systems are constructed. The effects of various pertinent parameters on the axial velocity and temperature distributions are analyzed graphically. The skin friction and the Nusselt number are computed numerically and graphically. 相似文献
105.
Basit Khalid Franz Ziegler 《Archive of Applied Mechanics (Ingenieur Archiv)》2012,82(10-11):1423-1437
The vulnerability of civil engineering structures with fundamental frequency, say roughly above 1?Hz, (or buildings having less than ten stories), when exposed to the strong motion phase of an earthquake is considerably reduced by means of base isolation. The low-pass filter for isolating horizontal vibrations is redesigned where the classical elastomeric bearings are substituted by a number of prestressed helical steel springs with pivoted columns along their vertical axes carrying a fraction of the dead weight and guiding the remaining horizontal motion. The base-isolated building in its fundamental mode is considered to be rigid and low-cost tuned liquid column gas dampers (TLCGDs), in optimal arrangement within the plan of the basement of the building, supply the effective damping of the remaining horizontal vibrations. TLCGD-tuning in a first step is performed by a simple transformation of the well-documented optimal parameters of the tuned mass damper (TMD) followed by fine-tuning in state space. The action of the passive damping device is commonly considered to be sufficient. Since the gas-spring effect somewhat counter acts changes in fluid mass, the absorber can be used as a water reservoir. Compatible sliding elements are innovatively designed to resist the motion of the building relative to the ground for sufficiently small disturbances by static friction, thus complete the isolation system. However, during seismic excitation, the frictional contact is released over much of the time to avoid excessive wear. 相似文献
106.
Let be a locally compact group equipped with right Haar measure. The right differences of functions on are defined by for . Let and suppose for some and all . We prove that is a right uniformly continuous function of . If is abelian and the Beurling spectrum does not contain the unit of the dual group , then we show . These results have analogues for functions , where is a separable or reflexive Banach space. Finally, we apply our methods to vector-valued right uniformly continuous differences and to absolutely continuous elements of left Banach -modules.
107.
Y. F. Shafiq M. A. A. Al-janabi M. A. M. Abdel-Azeez M. H. S. Al-Hissoni M. M. Jassim 《Journal of Radioanalytical and Nuclear Chemistry》1987,109(1):23-36
Correlation between the in vivo distribution and the chemical formulation of99mTc-PYP complex has been studied. We chose mice to evaluate in vivo biodistribution and gel chromatography column scanning technique for radiochemical analysis. The influence of the pH, Sn(II), pyrophosphate concentration and molar ratios of Sn: PYP on the labelling of pyp with99mTc has been investigated in vitro and in vivo. The reaction between99mTc and Sn-PYP was complete within a few minutes. The stability studies were evaluated against dilution. Induced myocardial infarction was evaluated in rats. The clinical evaluation showed excellent definition of sternum and ribs with little blood background activity with normal subjects. Discrete localization of abnormally high activity was shown in the site of recent infarction of the left ventricular myocardium. 相似文献
108.
In this study, Darcy Forchheimer flow paradigm, which is a useful paradigm in fields such as petroleum engineering where high flow velocity effects are common, has been analyzed with artificial intelligence approach. In this context, first of all, Darcy–Forchheimer flow of Ree–Eyring fluid along a permeable stretching surface with convective boundary conditions has been examined and heat and mass transfer mechanisms have been investigated by including the effect of chemical process, heat generation/absorption, and activation energy. Cattaneo–Christov heat flux model has been used to analyze heat transfer properties. Within the scope of optimizing Darcy–Forchheimer flow of Ree–Eyring fluid; three different artificial neural network models have been developed to predict Nusselt number, Sherwood number, and skin friction coefficient values. The developed artificial neural network model has been able to predict Nusselt number, Sherwood number, and skin friction coefficient values with high accuracy. The findings obtained as a result of the study showed that artificial neural networks are an ideal tool that can be used to model Darcy–Forchheimer Ree–Eyring fluid flow towards a permeable stretch layer with activation energy and a convective boundary condition. 相似文献
109.
Basit Shafiq M. Allauddin Usman Qaisrani Mumtaz A. Rehman Tauseef-ur- Ahmed Naveed Usman Mushtaq M. Ali Hafiz Muhammad 《Journal of Thermal Analysis and Calorimetry》2022,147(21):12111-12126
Journal of Thermal Analysis and Calorimetry - Heat exchangers serve as pivotal components in industries. Enhancement in the performance of heat exchangers has been the focus of researchers in the... 相似文献
110.
Muhammad Yaqub Javeria Batool Khalid Mahmood Abida Ashraf Ruqayia Perveen Zahid Shafiq 《Journal of heterocyclic chemistry》2020,57(8):3089-3104
A regioselective and convenient methodology was developed to synthesize heterocyclic derivatives, bearing imidazole, piperidines, and azepines rings. The N-arylnitrones derived from 3-formylchromones were selected to react with heterocyclic ketene aminal to furnish the structurally attractive and pharmacologically important fused ring heterocycles. The N-arylnitrone moiety of 3-formylchromone was used to activate the formyl group for regioselective fused ring heterocycles synthesis, whereas, the effect of substituents at aryl functionality of nitrones were studied to improve the yield of target fused ring heterocyclic products. The synthesized compounds (10-12) were evaluated for their in vitro cytotoxic and antifungal influences. In cytotoxic (brine shrimp lethality) assay, compound 11e was found to be active with LD50 = 4.1 × 10−6 μg/mL. 相似文献