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111.
112.
Hayat M. Marafie Mohammed S. El-Ezaby Bashir A. Abd-El-Nabey Nabil Kittaneh 《Transition Metal Chemistry》1982,7(4):227-233
Summary The stability constants of ternary CoII, NiII, CuII, ZnII and CdII complexes containing pyridoxamine as a first and ethylenediamine as a second ligand were determined by pH titration at I =0.50M NaNO3 and 30 °C. Most of the complexes are protonated, probably on the pyridoxamine moiety. The formation of the ternary complex species is discussed in terms of binary species formation. Spectral characteristics of some of the ternary complex systems are discussed.Part X. Binary, Ternary and Quaternary Complexes Involved in Systems of Pyridoxamine-Glycine or Glycylglycine-Imidazole with Some Bivalent Metal Ions,21st Internat. Conf. on Coord. Chem., Toulouse, France (1980); 相似文献
113.
Hallmann L Bashir A Strunskus T Adelung R Staemmler V Wöll Ch Tuczek F 《Langmuir : the ACS journal of surfaces and colloids》2008,24(11):5726-5733
The formation of self-assembled monolayers of benzylmercaptan (BM) and p-cyanobenzylmercaptan (pCBM) on Au(111) surfaces is investigated by a combination of X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS), and scanning tunneling microscopy (STM). The NEXAFS results of pCBM are supported by ab initio calculations. It is found that BM as well as pCBM form well-ordered monolayers with the molecules oriented almost perpendicular to the surface. BM forms a ( radical 3 x radical 3)R30 degrees structure whereas pCBM forms a slightly different c(7 x 7) hexagonal structure. No phase separation is detected for the adsorption of a 1:1 mixture of the two molecules. The implications of the results for the covalent attachment of transition-metal complexes to thiol-functionalized surfaces are discussed. 相似文献
114.
Amber Khuram Pervez Akram Waseem Bashir Muhammad Anser Khan Muhammad Sajid Kousar Anila 《Journal of Thermal Analysis and Calorimetry》2021,143(3):2355-2366
Journal of Thermal Analysis and Calorimetry - At higher ambient temperatures during summer months, the cell temperature of a photovoltaic (PV) module increases to 50–60 °C and sometimes... 相似文献
115.
Ahmed Alsaedi Bashir Ahmad Mokhtar Kirane Maryem Al‐Yami 《Mathematical Methods in the Applied Sciences》2017,40(4):1280-1287
Sufficient conditions are obtained for the nonexistence of solutions to the nonlinear higher order pseudo‐parabolic equation where is the Kohn‐Laplace operator on the (2N + 1)‐dimensional Heisenberg group , m≥1,p > 1. Then, this result is extended to the case of a 2 × 2‐system of the same type. Our technique of proof is based on judicious choices of the test functions in the weak formulation of the sought solutions. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
116.
A single-crystal CaF2 (111) was irradiated with single and multiple laser (Ti:sapphire, 800 nm, 25 fs) shots at fluences ranging from 0.25 to 1.5 J cm?2. In this fluence regime, a single laser pulse usually leads to typical bump-like features ranging from 200 nm to 1.5 μm in diameter and 10–50 nm in height. These bumps are related to compressive stresses due to a pressure build-up induced by fast laser heating and their subsequent relaxation. When CaF2 is irradiated with successive (in our case 20) shots at a laser fluence of 1.5 J cm?2, nanocavities at the top of the microbumps are observed. The formation of these nanocavities is regarded as an explosion and is attributed to the explosive expansion generated by shock waves due to laser-induced plasma after the nonlinear absorption of the laser energy by the material. Such kinds of surface structures at the nanometre scale could be attractive for nanolithography. 相似文献
117.
Background
The heterocyclic hydrazones constitute an important class of biologically active drug molecules. The hydrazones have also been used as herbicides, insecticides, nematocides, redenticides, and plant growth regulators as well as plasticizers and stabilizers for polymers. The importance of the phenolic quinolyl hydrazones arises from incorporating the quinoline ring with the phenolic compound; 2,4-dihydroxy benzaldehyde. Quinoline ring has therapeutic and biological activities whereas, phenols have antiseptic and disinfectants activities and are used in the preparation of dyes, bakelite and drugs. The present study is planned to check the effect of the counter anions on the type and geometry of the isolated copper(II)- complexes as well as the ligational behavior of the phenolic hydrazone; 4-[(2-(4,8-dimethylquinolin-2-yl)hydrazono)methyl] benzene-1,3-diol; (H2L). 相似文献118.
Shazia Bashir Nazar Farid Khaliq Mahmood M. Shahid Rafique 《Applied Physics A: Materials Science & Processing》2012,107(1):203-212
The ablation of Cd has been performed by employing Q-switched Nd: YAG 10 ns laser pulses with a central wavelength of 1064 nm
for a pulsed energy of 200 mJ under various ambient environments of argon, air and helium. The optical emission spectroscopy
of Cd plasma has been studied under different filling pressures of shield gases ranging from 5 torr to 760 torr using LIBS
spectrometer system. The effect of different gases and their pressures on the intensity of spectral emission, electron temperature
and density of the laser-produced plasma has been investigated. SEM analysis has been performed to investigate the dependence
of surface morphological changes of an irradiated target on the nature and pressure of an ambient gas. A strong correlation
has revealed the vital role of electron temperature and density of laser-induced plasma for the surface modification of Cd.
These results strongly indicate that the nature and pressure of the ambient atmosphere is one of the controlling factors of
the plasma characteristics, as well as the factors related to the laser energy absorption for surface modification. 相似文献
119.
Adnan Bashir CHANG Lei Ian C. Cloet Bruno El-Bennich LIU Yu-Xin Craig D. Roberts Peter C. Tandy 《理论物理通讯》2012,58(1):79-134
We survey contemporary studies of hadrons and strongly interacting quarks using QCD's Dyson-Schwinger equations, addressing the following aspects: confinement and dynamical chiral symmetry breaking; the hadron spectrum; hadron elastic and transition form factors, from small- to large-Q2; parton distribution functions; the physics of hadrons containing one or more heavy quarks; and properties of the quark gluon plasma. 相似文献
120.
Khashayar Rajabimoghadam Yousef Darwish Umyeena Bashir Dylan Pitman Sidney Eichelberger Maxime A. Siegler 《Journal of Coordination Chemistry》2019,72(8):1346-1357
AbstractIn this research article, we report the synthesis and structural characterization of a family of first-row metal complexes bearing redox-active ligands with tunable H-bonding donors. We observed that these coordination complexes can adopt three different geometries and that they are stabilized by intramolecular multicenter H-bonding interactions, which are systematically modified by changing the metal ion (Co, Ni, Cu, Zn), the ligand scaffold (variations in the diamine and ureanyl substituents used) and the solvent of crystallization. 相似文献