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101.
Selim Rehab E. Ahmed Hanaa H. Abd-Allah Somia H. Sabry Gilane M. Hassan Rasha E. Khalil Wagdy K. B. Abouhashem Nehal S. 《Applied biochemistry and biotechnology》2019,189(1):284-304
Applied Biochemistry and Biotechnology - Acute kidney injury (AKI) is a rapid loss of renal function. It has high mortality rates. Still, renal replacement therapy is considered the best solution... 相似文献
102.
Sabri S. Mahmoud Mohammed A. Hassan Fayez H. El-Khatib Ayman A. Obaidat Mutaz Sheikh-Salem 《Reaction Kinetics and Catalysis Letters》2000,70(1):119-124
Photodegradation of tenoxicam was investigated under different reaction conditions. After 60 min of exposure to UV light, the photodegradation was extensive, and the maximum and minimum in the UV-visible spectrum were shifted to shorter and longer wavelengths, respectively. Ethanol exerted a photostabilizing effect on tenoxicam. Tenoxicam is more stable in acidic and basic media than in neutral solution. Increasing light intensity or temperature causes an increase in the rate of photodegradation. The photodegradation of tenoxicam was found to follow first-order kinetics under all these conditions. 相似文献
103.
Seyyed Javad Sabounchei Hassan Nemattalab Sadegh Salehzadeh Sima Khani Mehdi Bayat Hamid Reza Khavasi 《Polyhedron》2008
Reaction of phosphorus ylide Ph3PCHC(O)C6H4Cl (Y1) with HgX2 (X = Cl, Br and I) and ylide (p-tolyl)3PCHC(O)CH3 (Y2) with HgI2 in equimolar ratios using methanol as solvent leads to binuclear products. The bridge-splitting reaction of binuclear complex [(Y1) · HgCl2]2 by DMSO yields a mononuclear complex containing DMSO as ligand. O-coordination of DMSO is revealed by single crystal X-ray analysis in mononuclear complex of [(Y1) · HgCl2 · DMSO]. C-coordination of ylides is confirmed by X-ray structure of binuclear complex [(Y2) · HgI2]2. Characterization of the obtained compounds was also performed by elemental analysis, IR, 1H, 31P, and 13C NMR. Theoretical studies on mercury(II) complexes of Y1 show that formation of mononuclear complexes in DMSO solution in which DMSO acts as a ligand, energetically is more favorable than that of binuclear complexes. 相似文献
104.
105.
Enantioselective, potentiometric membrane electrodes (EPMEs) based on carbon paste impregnated with different maltodextrins {dextrose equivalent (DE) 4.0-7.0 (I), 13.0-17.0 (II) and 16.5-19.5 (III)} as chiral selectors for the assay of S-perindopril is described. The proposed electrodes could be reliably employed in the assay of S-perindopril raw material and from its pharmaceutical formulation, Coversyl® tablets. The electrode based on maltodextrin (I) showed the best enantioselectivity and time-stability. The surfaces of the electrodes are easily renewable by simply polishing on an alumina paper. 相似文献
106.
Novel aromatic poly(benzimidazole-amide)s, PBAs, have been synthesized by direct polycondensation of a new dicarboxylic acid, N-[3,5-bis(5-carboxylic acid-2-benzimidazole) phenyl]phthalimide (1), containing performed benzimidazole rings and a phthalimide pendent group with various aromatic diamines. The dicarboxylic acid was synthesized by reaction of 5-(N-phthalimide)isophthalic acid with 4-methyl-1,2-phenylenediamine in polyphosphoric acid, followed by its oxidation into relative dicarboxylic acid. To study the structure-property relationships of 1,3-bis(5-carboxylic acid-2-benzimidazole)benzene (2, as a reference) this compound was also synthesized. The chemical structure of 1 and 2 were confirmed by the spectroscopic methods and elemental analyses. The characterization of the polymers was performed with inherent viscosity measurements, solubility tests, FT-IR, Ultraviolet and 1H NMR spectroscopy and thermogravimetry. The polymers were obtained in quantitative yields with inherent viscosities between 0.53 and 0.91 dl g−1. The effects of the phthalimide pendent group on the polymer properties such as solubility and thermal behavior were investigated and compared with those of the corresponding unsubstituted poly(benzimidazole-amide)s. The modified poly(benzimidazole-amide)s showed enhanced solubilities in some solvents, such as m-cresol and pyridine, in comparison to the unmodified analogues. In addition, the incorporation of the pendent phthalimide groups in the poly(benzimidazole-amide)s backbone increased remarkably the thermal stability of the polymer. The glass transition temperature and 10% weight loss temperature of the poly(benzimidazole-amide)s were in range of 291-334 °C and 466-540 °C, respectively, in nitrogen. 相似文献
107.
The structures of aggregates formed in aqueous solutions of an anionic surfactant, sodium dodecyl sulfate (SDS), with the addition of a cationic hydrotropic salt, p-toluidine hydrochloride (PTHC), have been investigated by small angle neutron scattering (SANS). The SANS spectra exhibit a pronounced peak at low salt concentration, indicating the presence of repulsive intermicellar interactions. Model-independent real space information about the structure is obtained from a generalized indirect Fourier transformation (GIFT) technique in combination with a suitable model for the interparticle structure factor. The interparticle interaction is captured using the rescaled mean spherical approximation (RMSA) closure relation and a Yukawa form of the interaction potential. Further quantification of the geometrical parameters of the micelles was achieved by a complete fit of the SANS data using a prolate ellipsoidal form factor and the RMSA structure factor. The present study shows that PTHC induces a decrease in the fractional charge of the micelles due to adsorption at the micellar surface and consequent growth of the SDS micelles from nearly globular to rodlike as the concentration of PTHC increases. 相似文献
108.
Potentiometric titration of phenols with sodium methoxide in dimethylformamide, with a glass-calomel electrode system, is limited to monohydric phenols substituted with electron-attracting groups and dihydric phenols in which the two -OH groups are substituted in isolated benzene rings. Brilliant Orange has proved to be a suitable indicator in the titration of all types of mono- and dihydric phenols. Titan Yellow is recommended as indicator for the titration of carboxylic acids. Simultaneous visual titration of -OH and -COOH groups is also described. A detailed study with 62 structurally different compounds covering the various groups is reported, and a suitable procedure for the microdetermination of each class of these compounds with an error of +/- 0.2% absolute or less is presented. 相似文献
109.
Summary New complexes of chromium(III), manganese(II) and nickel(II) with methylhydrazinecarboxylate (MeCz) and of manganese(II) and
nickel(II) with 1,1-dimethylhydra-zinecarboxylate (Me2Cz) were prepared by reacting salts of the metals with CO2-saturated solutions of the hydrazines in EtOH. The compounds [Cr(MeCz)3]·2H2O, Ni(MeCz)2(H2O)3·MMH, Mn(MeCz)2(H2O)2(MMH = monomethylhydrazine) and M(Me2Cz)2(H2O)2 (M = Mn or Ni) were investigated using d.t.a., t.g.a., electronic and i.r. spectroscopy and by magnetic susceptibility measurements. 相似文献
110.
Mohsen Keyvanfard Ali A. Ensafi Hassan Karimi-Maleh 《Journal of Solid State Electrochemistry》2012,16(9):2949-2955
The electro-oxidation of cysteamine (CA) and tryptophan (TP) were studied by vinylferrocene-modified carbon nanotubes paste electrode using cyclic voltammetry, chronoamperometry, electrochemical impedance spectroscopy, and square wave voltammetry. This modified electrode exhibits persistent electron-mediating behavior followed by well-separated oxidation peaks towards CA and TP with decreasing their overpotentials. For the mixture containing CA and TP, the peaks potential well separated from each other. Using the modified electrode, the kinetics of CA electrooxidation was considerably enhanced by lowering the anodic overpotential through a catalytic fashion. Using square wave voltammetry, simultaneous determination of AC and TP has been explored at the modified electrode. Their square wave voltammetrics peaks current increased linearly with their concentration at the ranges of 0.09–500 and 5.0–1,000?μM, respectively with the detection limits of 0.05 and 1.0?μM, respectively. The modified electrode was successfully used for the determination of the analytes in real samples with satisfactory results. 相似文献