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91.
Raif Kurtaran Cengiz Arici Kaan C. Emregül Diner Ülkü Orhan Atakol Mustafa Tatekin 《无机化学与普通化学杂志》2003,629(9):1617-1621
A homo‐dinuclear NiII complex was prepared from 2, 6‐bis(3, 5‐dimethylpyrazolyl)pyridine (Me4‐bpp) and azide ions in nonaqueous media. It was characterized by single crystal X‐ray structural analysis, IR spectroscopy, and elemental analysis. In addition, the electrochemical properties of the compound were determined with cyclic voltammetry in DMF. The title compound crystallizes in the P21/n monoclinic space group, with unit cell parameters a = 8.978(1), b = 12.459(1), c = 17.764(1) Å, ß =100.603(3)°, V = 1953.0(3) Å3, Z = 2. The Ni2+ ion has a distorted octahedral environment involving three nitrogen atoms of the Me4‐bpp ligand, two nitrogen atoms from the bridged azide group, and one nitrogen atom from the terminal azide group. The Ni···Ni distance is 3.273(5) Å. 相似文献
92.
Mustafa R. Ibrahim Zacharia A. Fataftah Paul von Ragu Schleyer Peter D. Stout 《Journal of computational chemistry》1987,8(8):1131-1138
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases. 相似文献
93.
Mohamed Hilmy Elnagdi Ramadan Maawad Abdel-Motaleb Mona Mustafa Mohamed Foad Zayed Eman Moustafa Kamel 《Journal of heterocyclic chemistry》1987,24(6):1677-1681
The behaviour of several 2-amino-3-cyano-4H-pyran derivatives toward a variety of nucleophilic reagents is reported. 相似文献
94.
Along with many factors, the change in protein tau isoforms, which has an obvious role in the function of microtubules, is an important biomarker of Alzheimer's disease. The aim of this study is to determine the protein Tau-441 with a portable potentiostat using a practical approach. For this purpose, screen printed electrodes (SPCEs) were first hydroxylated and then functional self-assembled monolayers were formed on the surface with 3-aminopropyltriethoxysilane (APTES). Evidence of anti-Tau being immobilized on to the surface was followed by techniques such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FTIR). The constructed immunosensor showed a linear response within the concentration range of 0.0064–0.8 ng/mL for the target analyte Tau-441 and the limit of detection was found to be 0.0053 ng/mL. In addition, analytical behaviors such as reproducible measurements and storage life of the developed immunosensor with a portable potentiostat were also investigated. It has been demonstrated that Tau-441 can be captured with the help of portable device with sensitivity in CSF environment. 相似文献
95.
Ozer Atakoglu Ozge Yalcin Mustafa Gurhan Ozmen Suleyman Fatih 《Journal of Radioanalytical and Nuclear Chemistry》2021,328(2):701-706
Journal of Radioanalytical and Nuclear Chemistry - Iron phosphate glasses with melting temperatures of?~?1300 °C were developed to immobilize spent nuclear fuels. The... 相似文献
96.
The photochemical and photophysical properties of peripheral and nonperipheral zinc and indium phthalocyanines containing 7‐oxy‐3,4‐dimethylcoumarin synthesized were investigated in this study. 7‐Hydroxy‐3,4‐dimethylcoumarin ( 1 ) was synthesized via Pechmann condensation reaction and then the phthalonitrile derivatives [4‐(7‐oxy‐3,4‐dimethylcoumarino)phthalonitrile ( 2 ) and 3‐(7‐oxy‐3,4‐dimethylcoumarino)phthalonitrile ( 3 )] were synthesized by nucleophilic aromatic substitution. Phthalocyanine compounds containing coumarin units on peripheral ( 4 and 5 ) and nonperipheral ( 6 and 7 ) positions were prepared via cyclotetramerization of phthalonitrile compounds. All compounds' characterizations were performed by spectroscopic methods and elemental analysis. The phthalocyanine derivatives' ( 4–7 ) photochemical and photophysical properties were studied in DMF. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen and photodegradation quantum yields) properties of these novel phthalocyanines ( 4 – 7 ) were studied in DMF. They produced good singlet oxygen (e.g., ΦΔ = 0.93 for 7 ) and showed appropriate photodegradation (in the order of 10?5), which is very important for photodynamic therapy applications. 相似文献
97.
Facile fabrication and characterization of polyimide nanofiber reinforced photocured hybrid electrolyte for Li‐ion batteries 下载免费PDF全文
In this study, a novel ion conductive polyimide (PI) nanofiber reinforced photocured hybrid electrolyte has been fabricated. Polyimide fibers were fabricated with the reaction between 4,4′‐oxydianiline (ODA) and 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (BTDA) followed by electrospinning and thermal imidization methods. Then, PI electrospun fibers were dipped into hybrid resin formulation containing bisphenol A ethoxylate dimethacrylate (BEMA), poly (ethylene glycol) methyl ether methacrylate (PEGMA) and 3‐(methacryloyloxy) propyltrimethoxysilane (MEMO) and then photocured to prepare PI nanofiber reinforced electrolyte membrane. Photocured membranes were soaked into lithium hexafluorophosphate (LiPF6) before measuring electrochemical stability and ionic conductivity of hybrid polyelectrolyte. The chemical structure and electrochemical performance of the electrolytes were examined by Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV) and scanning electron microscopy (SEM) analysis. The incorporation of MEMO into organic matrix effectively increased the modulus from 2.83 to 5.91 MPa. The obtained results showed that a suitable electrolyte for Li‐ion batteries with high lithium uptake ratio, high conductivity (7.2 × 10?3 S cm?1) at ambient temperature and wide stability window above 5.5 V had been prepared. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
98.
Lgaz Hassane Chaouiki Abdelkarim Albayati Mustafa R. Salghi Rachid El Aoufir Yasmina Ali Ismat H. Khan Mohammad I. Mohamed Shaaban K. Chung Ill-Min 《Research on Chemical Intermediates》2019,45(4):2269-2286
Research on Chemical Intermediates - Mild steel corrosion in HCl solution is an example of corrosion in acidic mediums. The ongoing research efforts to develop novel environmentally friendly... 相似文献
99.
Ammar Mustafa N. M. Mikhailova N. S. Prostakov 《Chemistry of Heterocyclic Compounds》1996,32(1):65-67
9-Phenacylidene-4-azaf luorene and 9-bromo-9-(-bromophenacyl)-4-azafluorene have been used in the synthesis of spiro compounds with fragments of substituted pyrazolines. 1-Methyl-2-oxo-5 phenacylidene-indeno[2, 3-e]-1,2-dihydropyridine and hydrazine gave 1-methyl-2-oxo-3 phenylspiro[indeno(2, 3-e)-1,2-dihydropyridine-5,5-pyrazoline-2]. 相似文献
100.
Adem Kili Saliha Bege Bekir etinkaya Tuncer Hkelek Zeynel Kili Necla Gündüz Mustafa Yildiz 《Heteroatom Chemistry》1996,7(4):249-256
Reactions of hexachlorocyclotriphosphazatriene, N3P3Cl6 1 , with sodium aryloxides have been studied. Compound 1 was found to react by the nucleophilic substitution pathway to yield monocyclophosphazenes [N3P3Cl6(OC6H2Bu13-2,4,6) 5 and N3P3Cl4(OC6H2Me-4-Bu12-2,6)2 6 ] and bi(cyclophosphazenes) ([Cl5N3P3-P3N3Cl4(OC6H3Bu12-2,6)] 7 and [N3P3(OC6H3Bu12-2,6)5]2 8 ). The unusual bi(cyclophosphazenes) 7 and 8 are the first examples of two cyclotriphosphazene rings linked by a P(SINGLE BOND)P bond [2.193 (2) Å], which have been obtained by reacting 1 with ArONa. The structures of compounds 5–8 are ascertained by elemental analyses, 1H-, 31P-13C-NMR, IR, and MS spectra. The molecular structure of monocyclic-phosphazene 5 was determined by X-ray diffraction techniques for further structural assignment. It crystallizes in the monoclinic space group P21/m with a = 6.144(2), b = 17.079(9), c = 13.181(9) Å, β = 92.79(7), and Z = 2, R = 0.074. Compound 5 is on a crystallographic mirror plane, and there is only a half molecule in the asymmetric unit. © 1996 John Wiley & Sons, Inc. 相似文献