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311.
Masood Parvez Saeed Anwar Amin Badshah Bashir Ahmad Abdul Majeed Muhammad Ashfaq 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):159-160
The crystal structure of the title compound, [Sn4(C4H9)8(C10H6NO4)4O2], contains centrosymmetric dimers. It contains a central Sn2O2 core with the O atoms bonded to two dibutylbis(N‐phthaloylglycinato)tin units. The Sn atoms of the core are six‐coordinate in a skew trapezoidal bipyramidal geometry, while the exocyclic Sn atoms are essentially five‐coordinate in a distorted trigonal geometry. The Sn—C distances lie in a narrow range of 2.120 (5)–2.138 (4) Å. 相似文献
312.
Coinage Metal Complexes of a Tellurium Diimide: cis→trans Isomerization and Metal–Metal Interactions
Tristram Chivers Masood Parvez Gabriele Schatte 《Angewandte Chemie (International ed. in English)》1999,38(15):2217-2219
The different coordination behavior of the ligand tBuN=Te(μ-NtBu)2Te=NtBu (L) towards Cu+ and Ag+ results from a cis→trans isomerization. The two Cu+ ions in [Cu2L3]2+ (shown schematically) bridge trans and cis isomers of the ligand, whereas the Ag+ ions in [Ag2L2]2+ link two trans ligands and exhibit a weak Ag⋅⋅⋅Ag interaction. 相似文献
313.
Vali Parvaneh Mahmoud Shariati Amir Masood Majd Sabeti 《European Journal of Mechanics - A/Solids》2009,28(6):1072-1078
In this paper, the influence of various vacancy defects on the critical buckling loads and strains in carbon nanotubes under axial compression is investigated via a new structural model in ABAQUS software. The necessity of desirable conditions and expensive tests for experimental methods, in addition to the time expenditure required for atomic simulations, are the motivation for this work, which, in addition to yielding accurate results, avoids the obstacles of the previous methods. In fact, this model is a combination of other structural models designed to eliminate the deficiencies inherent in individual approaches. Because the present model is constructed in the CAE space of ABAQUS, there is no need to program for different loading and boundary conditions. A nonlinear connector is considered for modeling of stretching and torsional interactions, and a nonlinear spring is used for modeling of the angle variation interactions. A Morse potential is employed for stretching and bending potentials, and a periodic type of bond torsion is used for torsion interactions. The effect of different types of vacancy defects at various locations on the critical buckling loads and strains is studied for zigzag and armchair nanotubes with various aspect ratios (Length/Diameter). Comparison of our results with those of buckling of shells with cutouts indicates that vacancy defects in the carbon nanotubes can most likely be modeled as cutouts of the shells. Finally, results of the present structural model are compared with those from molecular dynamics (MD) simulation and show good agreement between our model and the MD model. 相似文献
314.
Sadiq‐ur‐Rehman Saqib Ali Masood Parvez M. Mazhar Amin Badshah 《Heteroatom Chemistry》2004,15(5):398-406
The ligand, 3‐(3‐fluorophenyl)‐2‐phenylpropenoic acid, [C15H11FO2] ( I ) was prepared by reacting equimolar amount of phenyl acetic acid with 3‐fluorobenzaldehyde (1:1) using Perkin condensation method. The trimethyltin(IV) carboxylate, [Me3SnO2FH10C15] ( II ) was synthesized by refluxing an equimolar (1:1) mixture of trimethyltin chloride and silver salt of the ligand acid, [C15H10FO2Ag] ( Ia ). The ligand and complex both were characterized by elemental analysis, IR, mass, 1H NMR, and X‐ray crystallographic data. On the basis of 1H NMR data, (2J[117/119Sn, 1H] and C Sn C bond angle), it is concluded that the environment around the tin atom in solution is tetrahedral. The Infrared spectroscopic results showed that trimethyltin(IV) derivative has 5‐coordinated polymeric structure with bridging carboxylate groups in the solid state, which has been confirmed by the X‐ray crystallographic data. The crystal of ligand acid ( I ) is triclinic with space group Pbar1. However, the crystal of the complex ( II ) is monoclinic with space group C2/c. The geometry around the tin atom is distorted trigonal bipyramid with O(1) and O(2) atoms in apical positions. The ligand ( I ) and complex ( II ) were also tested for their biocidal activities. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:398–406, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20032 相似文献
315.
Theoretical investigation of amplitude modulation of ion sound waves is presented here for an electron–ion plasma where the electrons are dictated by the double spectral index (r, q) distribution function. Using the standard reductive perturbative technique, a non-linear Schrödinger (NLS) equation is derived that describes the evolution of modulated ion sound envelope excitations. Stability analysis of the NLS equation shows that the ion sound waves remain stable for the flat-topped and kappa-like distributions, but they can become unstable for the spiky electron velocity distribution. It is shown that changing the electron population in regions of low and high phase space density regions results in remarkable features that have no equivalent in ion sound waves with Boltzmannian electrons. Different types of localized ion sound excitations are plotted for the different shapes of the distribution functions controlled by the double spectral indices, and the underlying physics is discussed in detail. The present investigation may be beneficial to understand ion sound excitations in space plasmas where the distribution functions of the shapes presented here are frequently encountered by the satellite missions. 相似文献
316.
Halima Ghorbel-Feki Ali Masood Michael Caliez Michael Gratton Jean Christophe Pittet Martin Lints Serge Dos Santos 《Comptes Rendus Mecanique》2019,347(3):218-227
The mechanical behaviour of skin is significant for some applications including dermatology, surgery, and impact biomechanics science. In this work, we have investigated the study of the acousto-mechanical viscoelastic properties of skin. For that, both tensile-relaxation and ultrasonic tests were conducted on porcine tissue samples in fibre directions. To understand the complex skin aging phenomena, we used strength tensile test correlated with the Nonlinear Time Reversal signal processing tool extension “TR-NEWS”. Uniaxial tensile tests were carried out at a strain rate of on skin using a load-relaxation-discharge load path with increasing amplitude and offset. This work is also under way to extend the frequency range of ultrasounds to 50 MHz. Digital Image Correlation was used for 2D strain measurement of the dermis. From this analysis, we conclude that fresh porcine skin should be modelled as a nonlinear viscoelastic material with strain-rate dependence. The obtained hysteresis loop shall be taken as significant skin damage. 相似文献
317.
(Benzyl isocyanide)gold(I) pyrimidine‐2‐thiolate complex: Synthesis and biological activity
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Masood Fereidoonnezhad Hamid R. Shahsavari Elaheh Lotfi Mojgan Babaghasabha Motahareh Fakhri Zeinab Faghih Zahra Faghih M. Hassan Beyzavi 《应用有机金属化学》2018,32(3)
The reaction of [(Me2S)AuCl] with an equimolar amount of benzyl isocyanide (PhCH2NC) ligand led to the formation of complex [(PhCH2NC)AuCl] ( 1 ). The solid‐state structure of 1 was determined using the X‐ray diffraction method. Through a salt metathesis reaction, the chloride ligand in 1 was replaced by pyrimidine‐2‐thiolate (SpyN?) to afford the complex [(PhCH2NC)Au(η1‐S‐Spy)] ( 2 ), which was characterized spectroscopically. The cytotoxic activities of 1 and 2 were evaluated against three human cancer cell lines: ovarian carcinoma (SKOV3), lung carcinoma (A549) and breast carcinoma (MCF‐7). Complex 2 showed higher cytotoxicity than cisplatin against SKOV3 and MCF‐7 cancer cell lines. It showed a strong anti‐proliferative activity with IC50 of 7.80, 6.26 and 6.14 μM, compared with that measured for cisplatin which was 7.62, 12.36 and 11.47 μM, against A549, SKOV3 and MCF‐7 cell lines, respectively. The induction of cellular apoptosis by 2 was also studied on MCF‐7 cell line. Our results indicated that 2 could induce apoptosis in cancerous cells in a dose‐dependent manner. 相似文献
318.
Farzana Kouser Vijay Kumar Sharma Masood Rizvi Shaista Sultan Neha Chalotra Vivek K. Gupta Utpal Nandi Bhahwal Ali Shah 《Tetrahedron letters》2018,59(22):2161-2166
A visible light mediated radical addition of thiophenols on 4-phenylbut-3-enoic acids to give diastereoselective synthesis of 3,4-disubstituted γ-lactones is reported. The reaction precludes the conventional prerequisite of conjugate addition. Furthermore, the lactones were successfully utilized in the synthesis of γ-ketoamides. 相似文献
319.
Journal of Thermal Analysis and Calorimetry - In this article, the behavior of MHD hybrid nanofluid passing through a stretching sheet is examined. The current consideration also flashes the... 相似文献
320.