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321.
Waqas Jamil Darshana Kumari Muhammad Taha Muhammad Naseem Khan Mohd Syukri Baharudin Muhammad Ali M. Kanwal Muhammad Saleem Lashari Khalid Muhammad Khan 《Journal of the Iranian Chemical Society》2018,15(11):2441-2454
A series of 1,2,4-triazole hydrazones 1–25 has been synthesized and characterized using different spectroscopic techniques including FT-IR, 1H-NMR, and ESI MS spectrometry. The synthetic derivatives were evaluated for their β-glucuronidase enzyme inhibition properties. Among them, 17 compounds demonstrated potential inhibitory activity towards β-glucuronidase with IC50 values ranging between 2.50 and 53.70 µM. Compounds 1 having IC50?=?2.50?±?0.01 µM was found to be the most active compound of the series and showed remarkable activity and found to be far more potent than the standard d-saccharic acid 1,4-lactone (IC50?=?48.4?±?1.25 µM). Furthermore, the possible binding interaction of active compounds was explored by in silico studies. These compounds can be used for anti-diabetic drug development process. 相似文献
322.
The title compound crystallizes in the monoclinic space groupP21/a,a=11.50(2),b=7.724(1),c=12.599(3) Å,=102.22(5)°,Z=4. The structure was solved by direct methods and refined by full-matrix least squares toR=0.049 for 1032 observed reflections. The cobalt atom is -bonded to the cyclopentadienyl ring, with a mean Co-C distance of 2.07(1) Å, and also -bonded to the cyclonoatetraene ring at C(2)-C(3) and at C(6)-C(7), with a mean Co-C distance of 2.00(1) Å. 相似文献
323.
324.
STEAM, where the “A” represents arts and humanities, is considered a transdisciplinary learning process that has the potential to increase diverse participation in science, technology, engineering, and math (STEM) fields. However, a well‐defined conceptual model that clearly articulates essential components of the STEAM approach is needed to conduct empirical research on STEAM's efficacy–in particular, the teaching content that should be considered when enacting STEAM teaching practices. This paper proposes a conceptual model of STEAM, providing educators with the opportunity to teach effectively using transdisciplinary inquiry. The instructional content domain of the model includes problem‐based delivery, discipline integration, and problem‐solving skills. 相似文献
325.
Tariq Mahmud Rabia Rehman Aqsa Gulzar Amina Khalid Jamil Anwar Umer Shafique Muhammad Salman 《Arabian Journal of Chemistry》2010,3(4):219-224
Complexes of enaminones; 4-N,N-diethylamine-pent-3-ene-2-one [HL1], 4-N,N-di n-propylamine-pent-3-ene-2-one [HL2] and 4-N,N-dicyclohexylamine-pent-3-ene-2-one [HL3] with Fe(II) and Zn(II) ions were prepared by reacting the equimolar ethanolic solutions of the ligands (HL1, HL2 and HL3) with ethanolic metal solutions. The complexes formed, were characterized by infrared, ultraviolet and atomic absorption spectroscopy. Ligands and their metal complexes were tested against Escherichia coli and Staphylococcus aureus bacteria to assess their antibacterial action using disc diffusion method. Ligands were completely inactive against bacteria whereas the complex Zn (HL1) has significant action on both bacteria, indicating that it has a good potential as bactericide. Other complexes have normal antiseptic character. 相似文献
326.
K.?KaramiEmail author A.?Sheykhi M.?Jamil Z.?Azarmi M.?M.?Soltanzadeh 《General Relativity and Gravitation》2011,43(1):27-39
Motivated by a recent work of one of us (Sheykhi in Phys Rev D 81: 023525, 2010), we extend it by using quantum (or entropy)
corrected new agegraphic dark energy in the Brans–Dicke cosmology. The correction terms are motivated from the loop quantum
gravity which is one of the competitive theories of quantum gravity. Taking the non-flat background spacetime along with the
conformal age of the universe as the length scale, we derive the dynamical equation of state of dark energy and the deceleration
parameter. An important consequence of this study is the phantom divide scenario with entropy-corrected new agegraphic dark
energy. Moreover, we assume a system of dark matter, radiation and dark energy, while the later interacts only with dark matter.
We obtain some essential expressions related with dark energy dynamics. The cosmic coincidence problem is also resolved in
our model. 相似文献
327.
ZnO nanoparticles (NPs) have been successfully synthesized by the simple solution method at low temperature. The effects of annealing temperature on the structure and optical properties of ZnO NPs were investigated in detail by X-ray diffraction, transmission electron microscopy (TEM), ultraviolet–visible (UV–vis) spectroscopy and photoluminescence (PL) measurements. As the annealing temperature was increased above 180 °C the particles morphology evolved from spherical to hexagonal shape, indicating that the average particle size increased from 11 nm to 87 nm. The UV-vis and PL spectra showed a red-shift from 3.62 to 3.33 eV when the annealing temperature was increased. 相似文献
328.
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
329.
For more than 20 years nuclear physicists have used the GEANT code to simulate particle-matter interaction. In most recent version, GEANT4 is a toolkit for simulating the passage of particles though matter, which contains a complete range of functionality including tracking, geometry, physics models, and hits. In this article, an attempt to use GEANT4 to model a double-gap resistive plate chamber (RPC) with its improved efficiency is presented. The efficiencies of the double-gap RPC have been evaluated as a function of gamma energy range 0.005-1000MeV. A comparison to available previous simulation package GEANT3 data is also performed. 相似文献
330.
Héla Habli Leila Mejrissi Noureddine Issaoui Saud Jamil Yaghmour Brahim Oujia Florent Xavier Gadéa 《International journal of quantum chemistry》2015,115(3):172-186
The potentials, spectroscopic properties and electric dipole moments of SrH+ are computed for 63 molecular states dissociating up to Sr2+ + H? using an ab initio approach. The ab initio formalism is based on large basis sets, nonempirical atomic pseudopotential for strontium core, correlation treatment for core valence through the effective core polarization potentials and for valence through full valence configuration interaction. Our theoretical molecular constants match published values very well and a large amount of new results is produced. Unusual potential shapes are found in 1Σ+ states often caused by avoided crossing series between them and imprinted by the ionic state Sr2+H?. The high potential energy curves suggest, it is possible to form H? or at least to neutralize H+ in collisions with strontium. © 2014 Wiley Periodicals, Inc. 相似文献