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971.
Jian Fuh Ong Ithnin Abdul Jalil Wan Ahmad Tajuddin Wan Abdullah 《International Journal of Theoretical Physics》2013,52(3):679-688
We study the $\overline{\nu}_{e}-e$ scattering from low to ultrahigh energy in the framework of Higgs Triplet Model (HTM). We add the contribution of charged Higgs boson exchange to the total cross section of the scattering. We obtain the upper bound $h_{ee}/M_{H^{\pm}}\lesssim2.8\times10^{-3}~\mbox{GeV}^{-1}$ in this process from low energy experiment. We show that by using the upper bound obtained, the charged Higgs contribution can give enhancements to the total cross section with respect to the SM prediction up to 5.16 % at E≤1014 eV and maximum at $s\approx M_{H^{\pm}}^{2}$ and would help to determine the feasibility experiments to discriminate between SM and HTM at current available facilities. 相似文献
972.
Md. Abdul Khan 《Few-Body Systems》2014,55(11):1125-1139
The energies of the low-lying bound S-states of some two-electron systems (treating them as three-body systems) like negatively charged hydrogen, neutral helium, positively charged-lithium, beryllium, carbon, oxygen, neon, argon and negatively charged muonium and exotic positronium ions have been calculated employing hyperspherical harmonics expansion method. The matrix elements of two-body interactions involve Raynal–Revai coefficients which are particularly essential for the numerical solution of three-body Schr?dinger equation when the two-body potentials are other from Coulomb or harmonic. The technique has been applied for to two-electron ions 1H? (Z = 1) to 40Ar16+ (Z = 18), negatively charged-muonium Mu? and exotic positronium ion Ps?(e + e ? e ?) considering purely Coulomb interaction. The available computer facility restricted reliable calculations up to 28 partial waves (i.e. K m = 28) and energies for higher K m have been obtained by applying an extrapolation scheme suggested by Schneider. 相似文献
973.
Niken Taufiqurrahmi Abdul Rahman Mohamed Subhash Bhatia 《Journal of nanoparticle research》2011,13(8):3177-3189
Nanocrystalline zeolites with crystal size smaller than 100 nm are potential replacement for conventional zeolite catalysts
due to their unique characteristics and advantages. In this study, the synthesis of nanocrystalline zeolite Y (FAU) and nanocrystalline
zeolite beta (BEA) under hydrothermal conditions is reported. The effect of crystal size on the physico-chemical characteristics
of the zeolite, Y (FAU), and beta (BEA) is reported. The properties of nanocrystalline zeolites Y and Beta with crystal size
around 50 nm are compared with the microcrystalline zeolite Y and microcrystalline zeolite beta, respectively. The performance
of the nanocrystalline zeolite as a catalyst was investigated in the cracking of used palm oil for the production of biofuel.
The nanocrystalline zeolite catalytic activity was compared with the activity of microcrystalline zeolite in order to study
the effect of crystal size on the catalytic activity. Both nanocrystalline zeolites gave better performance in terms of conversion
of used palm oil as well as selectivity for the formation of gasoline fraction. The increase in surface area and improved
accessibility of the reactant in nanocrystalline zeolites enhanced the cracking activity as well as the desired product selectivity. 相似文献
974.
The magnetic properties of tetragonal structure of stoichiometric NiMn alloy is investigated using density functional theory within the local spin density approximation. The system studied here, is a free standing film. The effect of thickness and epitaxial strain on the magnetic and structural properties is examined. It is found that while the magnetic moments of Mn surface atoms vary depending on the number of layers being odd (3.60 ) or even (3.55 ) the magnitude of the magnetic moment for surface Ni atoms is constant (0.11 ). By applying epitaxial strain on the slabs, it was observed, for the first time, that the magnetic phase of NiMn films changes from “A-type-like” ferrimagnetic for compressive strains to “G-type-like” ferrimagnetic for tensile strains. 相似文献
975.
The metal complex (5,10,15,20‐tetrakis‐(4‐sulfonatophenyl)‐porphyrin‐iron (III) chloride (FeTSPP) was new employed in an environmentally benign protocol as an efficient catalyst for a “click” chemistry approach for the synthesis of tetrazole and guanindinyltetrazole derivatives via [2 + 3] cycloaddition reaction of nitriles and azide derivatives in aqueous medium. The synthesized compounds were obtained in excellent yield, short reaction times and a recoverable catalyst. 相似文献
976.
This article presents the optical properties of Tb3+ in lead fluoroborate glasses of the type X PbF2·(89–X)B2O3·10 Al2O3·1Tb2O3 (where X=8, 12, 16, 20, 24, 28, 34 and 36). The standard Judd–Ofelt model was applied to the room temperature absorption intensities of Tb3+ (4 f8) to determine the phenomenological intensity parameters Ω2, Ω4 and Ω6. These parameters have been used to calculate radiative transition probabilities (Arad), lifetimes (τR) and branching ratios (βR) for the excited level 5D4. The predicted values of τR are compared with the measured values for 5D4 level for eight glass compositions (Glass (A–H)). Among the eight-terbium glasses Glass A with 8 mol% of PbF2 (as the optimum content) has revealed an intense green emission with maximum life time and higher quantum efficiency. The stimulated emission cross section σ(λP) is also evaluated for the 5D4→7FJ (J=6, 5, 4 and 3) transitions. 相似文献
977.
Bushra Nisar Syeda Laila Rubab Abdul Rauf Raza Sobia Tariq Ayesha Sultan Muhammad Nawaz Tahir 《Molecular diversity》2018,22(3):709-722
Novel and highly sensitive indole-based imines have been synthesized. Their synthesis has been compared employing a variety of protocols. Ultimately, a convenient, economical and high yielding set of conditions employing green chemistry have been designed for their synthesis. 相似文献
978.
Abdul Ghani Zuleen Delina Fasya Ab Rashid Ahmad Hazri Shaari Khozirah Chik Zamri 《Applied biochemistry and biotechnology》2019,189(2):690-708
Applied Biochemistry and Biotechnology - The present studies are to evaluate the ability of PB to induce weight loss and urine metabolite profile of Piper betle L. (PB) leaf extracts using... 相似文献
979.
Abdul‐Majid Wazwaz 《Mathematical Methods in the Applied Sciences》2012,35(7):845-856
In this paper, we present a reliable study on extensions of the Bratu problem with boundary conditions. The work rests mainly on Adomian decomposition method and Padé approximants. The study shows a variety of approximations, one for each extension. The work highlights the effect of the extensions on the structure of the approximate solutions. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
980.
Akbar Ali Muhammad Khalid Saba Abid Javed Iqbal Muhammad Nawaz Tahir Abdul Rauf Raza Julio Zukerman-Schpector Marcio Weber Paixão 《应用有机金属化学》2020,34(3):e5399
The pyridine-based halogenated hydrazone derivatives (E)-N′-benzylidene-2-[(6″-chloroazin-2″-yl)oxy]acetohydrazide ( 6a ), (E)-N′-(3′-chlorobenzylidene)-2-[(6″-chloroazin-2″-yl)oxy]acetohydrazide ( 6b ) and (E)-N′-(3′-bromobenzylidene)-2-[(6″-chloroazin-2″-yl)oxy]acetohydrazide ( 6c ) have been obtained using 6-chloro-2-hydroxypyridine. The structure of the products ( 6a – c ) has been verified using X-ray crystallography and spectroscopic approaches. A single-crystal X-ray diffraction (SC-XRD) investigation showed that the structures are stabilized by intermolecular attractive forces. Additionally, density functional theory (DFT) has been adopted to explore the structural properties, vibrational spectra, noncovalent interactions and frontier molecular orbitals using the B3LYP/6-311 + G(d,p) level. The nonlinear optical properties of the title compounds were calculated using the CAM-B3LYP/6-311 + G(d,p) level. Frequency analysis confirmed the stability of the molecules, and an excellent correlation was observed between the DFT- and SC-XRD-based structural parameters. The SC-XRD analysis confirmed that the dimers of 6a , 6b and 6c are linked by hydrogen-bonding interactions. Natural bond orbital (NBO) analysis also reconfirmed the strength of intermolecular hydrogen-bonding and hyperconjugative interactions. NBO investigation was also utilized to analyze the atomic charges. Moreover, Fourier transform infrared and natural population analyses endorsed that there are significant N&bond;H⋅⋅⋅O&dbond;C hydrogen-bonding linkages in dimeric structures of the compounds. The hydrogen-bonding network and different sorts of hyperconjugative interactions are the main reasons for the stability of the products in the solid state. The highest occupied and lowest unoccupied molecular orbital energies and first-order nonlinear optical properties of these molecules are reported. The quantum chemical parameters were derived using frontier molecular orbital energies. 相似文献