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Mohammed M.?HashemiEmail author Zahed?Karimi-Jaberi 《Monatshefte für Chemie / Chemical Monthly》2004,135(1):41-43
Summary. A mixture of cobalt(II) and manganese(II) salts of 4-aminobenzoic acid supported on silica gel catalyses the oxidation of thiols to disulfides in the presence of oxygen or air. 相似文献
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OBJECTIVES: To provide data on the cytogenetics and epidemiology of Down syndrome in our community. METHODS: All cases of Down syndrome diagnosed cytogenetically were entered over a period of 5 years together with data regarding age at referral, parental ages and parity. RESULTS: A total of 280 cases were entered. In postnatal cases, the mean maternal age was 32.19 years and 41.5% of mothers were over 35 years. Only 47.3% of Down syndrome children were diagnosed at less than 1 month of age. The male to female sex ratio of 1.66 is significantly more elevated than that reported in larger registers. CONCLUSIONS: Because of problems inherent to Lebanon, this register does not have a high level of ascertainment, however it appears that the emphasis in a potential prevention programme should be placed on education, information and family planning. 相似文献
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Khalil Farhadi Sepideh Banisaeid Arezu Jamali Hamid Zebhi Zahed Ghelichkhah Hedayat Khalili Robab Abbasi 《中国化学会会志》2015,62(12):1149-1154
Electrochemical polymerization of tyramine was achieved on copper electrode surface from tyramine in 0.3 M oxalic acid (pH=1.2) solution by using cyclic voltammetry technique. The formation of polytyramine nanoparicles (PTN) were characterized by cyclic voltammetry (CV), fourier transform infrared‐attenuated total reflectance (FTIR‐ATR) spectroscopy and scanning electron microscopy (SEM). The corrosion behavior of PTN coated copper was investigated by means of the change of open circuit potential with exposure time (Eocp t), electrochemical impedance spectroscopy (EIS) and anodic polarization curves in 3.5 % NaCl solutions at room temperature. The obtained results showed the shift of corrosion potential toward positive values for electropolymerized copper and a significant decrease in corrosion current and corrosion rate in comparison with bare copper, so that the PTNs coating could be used as an important protection against corrosion of copper. 相似文献
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A mixture of cobalt(II) and manganese(II) salts of 4-aminobenzoic acid supported on silica gel catalyses the oxidation of thiols to disulfides in the presence of oxygen or air. 相似文献
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Seyed Mojtaba Amininasab Azad Rashidi Mehdi Taghavi Zahed Shami 《Polymer Science Series B》2016,58(6):712-719
Two series of new organosoluble and thermally stable polyimides containing anthracene, and fluorene pendants were prepared by a two-step solution polycondensation reaction of new synthesized diamines with commercially available dianhydrides. All intermediates and polymers were fully characterized by FTIR, NMR, and elemental analysis and their properties including solubility and thermal stability were studied. All the resulting polymers were amorphous with inherent viscosities ranged from 0.61 to 0.84 dL/g and were readily soluble in many organic solvents. 相似文献