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排序方式: 共有50条查询结果,搜索用时 343 毫秒
1.
MM. J. Duflos D. Letouz G. Queguiner P. Pastour 《Journal of heterocyclic chemistry》1973,10(6):1083-1084
This communication describes the synthesis of l-methyl-2,3-diformylpyrrole. This new compound is used to prepare a new heterocycle, l-methylcyclohepta[b]pyrrol-6-one and thus allows a new synthesis of l-methylpyrrolo[2,3-d]pyridazine. 相似文献
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A. Mohammad R. Gupta Nazrul Haq Mu. Naushad G. E. El-Desoky 《Journal of Dispersion Science and Technology》2013,34(8):1179-1184
Aqueous ethylene glycol (ethane 1,2 diol) as a green mobile phase has been used for thin layer chromatographic (TLC) studies of cationic surfactants on alumina layers. Nineteen solvent systems were used to examine the mobility of the surfactants and to discover the best TLC system for the selective separation of dodecyl trimethylammonium bromide (DTAB) from multi-component mixture of other surfactants. Among the TLC systems studied, M3 (ethylene glycol: water, 8:2) was best for achieving the selective separation of DTAB from multi-component mixture of other surfactants because in this mobile phase mobility of all surfactants except DTAB were insignificant. Effect of organic additives in aqueous ethylene glycol mobile phase on the mobility of surfactants was examined. The results obtained on laboratory made alumina TLC plates and commercially available precoated alumina HPTLC plates were compared. The lower limits of detection of DTAB, CPC, CTAB, HDTAC, and TTAB were 0.02, 0.05, 0.04, 0.06, or 0.08 µg per zone respectively. The resolution of mixture of cationic surfactants was also examined in the presence metal cations as an impurity in the analyzed sample. 相似文献
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Mahrous Awad M. A. El-Desoky A. Ghallab Jan Kubes S. E. Abdel-Mawly Subhan Danish Disna Ratnasekera Mohammad Sohidul Islam Milan Skalicky Marian Brestic Alaa Baazeem Saqer S. Alotaibi Talha Javed Rubab Shabbir Shah Fahad Muhammad Habib ur Rahman Ayman EL Sabagh 《Molecules (Basel, Switzerland)》2021,26(11)
Accumulation of heavy metals (HMs) by ornamental plants (OPs) from contaminated agriculture soils is a unique technique that can efficiently reduce the metal load in the food chain. Amaranthus tricolor L. has attractive characteristics acquiring a higher growth rate and large biomass when grown at heavy metal contaminated soils. Site-specific detailed information is not available on the use of A. tricolor plant in metal phytoremediation from the polluted sites. The study aimed to enhance the uptake of HMs (Pb, Zn, and Cu) via amending poultry litter extract (PLE), vinasse sugarcane (VSC), and humic acid (HA) as natural mobilized organic materials compared to ethylene diamine tetraacetic acid (EDTA), as a common mobilized chemical agent by A. tricolor plant. The studied soils collected from Helwan, El-Gabal El-Asfar (Cairo Governorate), Arab El-Madabeg (Assiut Governorate), Egypt, and study have been conducted under pot condition. Our results revealed all organic materials in all studied soils, except EDTA in EL-Gabal El-Asfar soil, significantly increased the dry weight of the A. tricolor plant compared to the control treatment. The uptake of Pb and Zn significantly (p > 0.05) increased due to applying all organic materials to the studied soils. HA application caused the highest uptake as shown in Pb concentration by more than 5 times in Helwan soil and EDTA by 65% in El-Gabal El-Asfar soil while VSC increased it by 110% in El-Madabeg soil. Also, an increase in Zn concentration due to EDTA application was 58, 42, and 56% for Helwan, El-Gabal El-Asfar, and El-Madabeg soil, respectively. In all studied soils, the application of organic materials increased the remediation factor (RF) than the control. El-Madabeg soil treated with vinasse sugarcane gave the highest RF values; 6.40, 3.26, and 4.02% for Pb, Zn, and Cu, respectively, than the control. Thus, we identified A. tricolor as a successful ornamental candidate that, along with organic mobilization amendments, most efficiently develop soil health, reduce metal toxicity, and recommend remediation of heavy metal-contaminated soils. Additionally, long-term application of organic mobilization amendments and continued growth of A. tricolor under field conditions could be recommended for future directions to confirm the results. 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - A mobile phase system comprising of ethyl acetate and propionic acid in 1:1 (v/v) ratio was identified as the most suitable green... 相似文献
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Ghoneim MM El-Desoky HS Abdel-Galeil MM 《Bioelectrochemistry (Amsterdam, Netherlands)》2011,81(2):65-73
Naltrexone HCl (NAL.HCl) has been reduced at the mercury electrode in Britton-Robinson universal buffer of pH values 2-11 with a mechanism involving the quasi-reversible uptake of the first transferring electron followed by a rate-determining protonation step of its C=O double bond at position C-6. Simple, sensitive, selective and reliable linear-sweep and square-wave adsorptive cathodic stripping voltammetry methods have been described for trace quantitation of NAL.HCl in bulk form, commercial formulation and human body fluids without the necessity for sample pretreatment and/or time-consuming extraction steps prior to the analysis. Limits of quantitation of 6.0×10(-9)M and 8.0×10(-10)M NAL.HCl in bulk form or commercial formulation and of 9.0×10(-9) and 1.0×10(-9)M NAL.HCl in spiked human serum samples were achieved by the described linear and square-wave stripping voltammetry methods, respectively. Furthermore, pharmacokinetic parameters of the drug in human plasma samples of healthy volunteers following the administration of an oral single dose of 50mg NAL.HCl (one Revia(?) tablet) were estimated by means of the described square-wave stripping voltammetry method without interferences from the drug's metabolites and/or endogenous human plasma constituents. The estimated pharmacokinetic parameters were favorably compared with those reported in literature. 相似文献
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Mohamed M. Ghoneim Hanaa S. El-Desoky Mohamed M. Abdel-Galeil 《Bioelectrochemistry (Amsterdam, Netherlands)》2011,80(2):162-168
Nitroxoline has been reduced at the mercury electrode in buffered solutions (pH 2?11) in two irreversible cathodic steps. The first step was attributed to reduction of –NO2 group to the hydroxylamine stage and the second one to reduction-saturation of the C=N double bond. DC-polarographic and various adsorptive stripping voltammetric methods were developed for determination of nitroxoline in bulk form. Limits of quantitation of 1.02 × 10?6, 3.05 × 10?8, 9.01 × 10?9, and 9.12 × 10?10 M nitroxoline were achieved by means of the developed DC-polarography, differential-pulse-, linear-sweep-, and square-wave-adsorptive cathodic stripping voltammetric methods, respectively. All these electroanalytical methods were successfully applied for determination of nitroxoline in its Nibiol® tablets. While only the developed adsorptive stripping voltammetry methods were successfully applied for determination of the drug in spiked human serum and for pharmacokinetic studies in real human plasma. The analysis was carried out without interference from common excipients and without the necessity for prior extraction or interaction with any reagent during the analysis. 相似文献
10.
MM. P. Duballet A. Godard G. Queguiner P. Pastour 《Journal of heterocyclic chemistry》1973,10(6):1079-1080
This article describes the synthesis of a new heterocycle, pyrido[2,3,f]phtalazine and three new diformylquinolincs. 相似文献