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排序方式: 共有331条查询结果,搜索用时 15 毫秒
1.
Mousa Z. Al-Noaimi Raid J. Abdel-Jalil Mustafa M. El-Abadelah Salim F. Haddad Younis N. H. Baqi Wolfgang Voelter 《Monatshefte für Chemie / Chemical Monthly》2006,37(12):745-750
In the presence of RuCl3, N-phenylamidrazone underwent oxidative cyclization into 1,4-dihydro-1-phenyl-1,2,4-benzotriazine, the structure of which is
established by spectral and X-ray diffraction data. 相似文献
2.
A.H.N. Mousa 《Journal of fluorine chemistry》1985,30(1):29-35
A sample of benzotrifluoride was degassed in a high vacuum train, and the vapor pressure was measured in the temperature range 460 – 53OK. Also the saturated vapour and saturated liquid volumes were measured. Two simple equations were used to fit the vapour pressure data by the least square method. The heat of vaporization was calculated using Clapeyron equation. 相似文献
3.
Summary Sodium alginate sol can be converted into ionotropic gels by diffusion of di/or trivalent metal ions. The kinetics of this phase transition is studied by two different methods. It is found that the rate of gel membrane formation at the earlier stages is greater than that of the further gel growth. The kinetic studies of gel formation in the presence of a mixture of Cu2+ ions with either Co2+ or Ni2+ ions show that the exhaust of Co2+ and Ni2- ions is remarkable only at the first stage of gel formation. Meanwhile the Cu2+ ions continue exchanging all the time with Na2+ ions in the alginate sol. The activation energy of gel formation is found to range between 17–23 kJ mol–, indicating the diffusion control of the process.With 6 figures and 3 tables 相似文献
4.
The many fold aromatic ketones 2a‐d are versatile compounds for the synthesis of the many fold 1,2,3‐selenadiazole aromatic derivatives 5a‐d . The preparation starts with the reaction between the many fold bromomethylene benzene derivatives 1a‐d and 4‐hydroxyacetophenone, which are transformed through the reaction with semicarbazide hydrochloride or ethylhydrazine carboxylate into the corresponding semicarbazones derivatives 3a‐d or hydrazones 4a‐d . The reaction with selenium dioxide leads to regiospecific ring closure of semicarbazones or hydrazones to give the many fold 1,2,3‐selenadiazole aromatic derivatives in high yield. 相似文献
5.
M. A. Mousa 《Journal of Radioanalytical and Nuclear Chemistry》1987,118(1):33-43
The electrical conductivity and IR-spectra of pure and Cu-doped Fe3O4 spinels were measured at 300–1000 K. Two breaks in the conductivity-temperature curves have been observed for all investigated pure and doped samples. One of these two breaks were found near the Curie point of the investigated spinel. The electrical conduction in -irradiated and non-irradiated pure and Cu-doped Fe3O4 occurred by a hopping mechanism due to a fast electron exchange between Fe2+ and Fe3+-ions present on octahedral sites. The Seebeck-voltage of the irradiated and non-irradiated pure and Cu-doped samples has been measured. The effect of -irradiation on the conductivity values //, activation energy and type of defects was discussed. 相似文献
6.
The inhibition performance of five azomethine derivatives such as: 1-(4-Methyloxy phenylimino)-1-(phenylhydrazono)-propan-2-one (SB1), 1-(4-Methylphenylimino)-1-(phenylhydrazono) propan-2-one (SB2), 1-(phenylimino)-1(phenylhydrazono)-propan-2-one (SB3), 1-(4-Bromo phenylimino)-1(phenylhydrazono)-propan-2-one (SB4) and 1-(4-Chlorophenylimino)-1(phenylhydrazono) -propan-2-on (SB5) as corrosion inhibitors for mild steel in sulfuric acid 0.5 ?M were investigated using different methods. All experimental results demonstrate that these compounds are eficients inhibitors. The inhibition efficiencies () increase with inhibitors concentration. At 7.5 10?5 ?M, the was 97.27%, 96.31%, 94.23%, 93.19 and 91.64% for SB1, SB2, SB3, SB4 and SB5, respectively. The potentiodynamic polarization results indicated that all the studied inhibitors act as mixed type. The adsorption process on mild steel surface obeyed Langmuir isotherm. The associated activation parameters and thermodynamic have been calculated and discussed. The adsorbed film formed on the metal surface was characterized by SEM and EDX. 相似文献
7.
A series of 1-methyl-2-methyleneacenaphthenes has been synthesized, bearing an additional variable substituent (R) at the 1-position. These compounds have been hydrogenated in ethanol over a 5% Pd/C catalyst under standardized conditions in order to assess the haptophilicity of R, its ability to enforce addition of hydrogen from its own face of the molecule by coordination to the catalyst surface. The order of decreasing haptophilicity, assessed as the product epimer ratio, for the groups studied was R = CH(2)NH(2), CH(2)NMe(2), CH(2)OH, CHNOH, CH(2)OMe, CHO, CONH(2), CH(2)NHCOMe, COOK, COMe, CN, CONHOH, COOH, COOMe, COONa, COOLi. Because knowledge of group haptophilicities offers potential for stereochemical control in such reductions, comparisons are provided with haptophilic orders found in other molecular systems. It is shown that absolute haptophilicities can be manipulated by varying the dielectric constant of the solvent employed. 相似文献
8.
Tayel A. Al Hujran Mousa K. Magharbeh Almeqdad Y. Habashneh Rasha S. Al-Dmour Ashraf Aboelela Hesham M. Tawfeek 《Molecules (Basel, Switzerland)》2022,27(14)
The study aims to assess the interaction between fluconazole and sulfonatocalix[4]naphthalene towards enhancing its dissolution performance and antimycotic activity. A solubility study was carried out at different pH conditions, and the results revealed the formation of a 1:1 molar ratio fluconazole-sulfonatocalix[4]naphthalene inclusion complex with an AL type phase solubility diagrams. The solid powder systems of fluconazole-sulfonatocalix[4]naphthalene were prepared using kneaded and co-evaporation techniques and physical mixtures. DCS, PXRD, TGA-DTG, FT-IR, and in vitro dissolution performance characterize the prepared systems. According to physicochemical characterization, the co-evaporation approach produces an amorphous inclusion complex of the drug inside the cavity of sulfonatocalix[4]naphthalene. The co-evaporate product significantly increased the drug dissolution rate up to 93 ± 1.77% within 10 min, unlike other prepared solid powders. The antimycotic activity showed an increase substantially (p ≤ 0.05, t-test) antimycotic activity of fluconazole co-evaporate mixture with sulfonatocalix[4]naphthalene compared with fluconazole alone against clinical strains of Candida albicans and Candida glabrata. In conclusion, sulfonatocalix[4]naphthalene could be considered an efficient complexing agent for fluconazole to enhance its aqueous solubility, dissolution performance, and antimycotic activity. 相似文献
9.
Saleh Al-Omari Nawash Alghezawi Mousa Al-Noaimi Akram Aqili Ibrahim F. Al-Hamarneh Mohammad Marashdeh 《Journal of fluorescence》2014,24(3):835-839
The shift of the Q-band of sodium zinc(II)-2,9,16,23-phthalocyanine tetracarboxylate (ZnPc(COONa)4) to about 800 nm is attributed to the influence of the electron-donating property of the carboxylate groups substituted in the β–position. ZnPc(COONa)4 which was found to have a symmetry of D 2h characterized by a splitting of the Q transition. This splitting was interpreted by the formation of dianionic symmetric ZnPc(COONa)4 resulting from the dissociation of the pyrrole protons as well as the possibility of Na+ dissolution of ZnPc(COONa)4 in the aqueous solution of NaOH. 相似文献
10.