- Synthesis, Surface and Antimicrobial Activities of Cationic Gemini Surfactants with Semi-Rigid Spacers
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Four cationic gemini surfactants featuring semi-rigid spacers were synthesized via a two-step process. The surface-active properties of these surfactants were investigated through surface tension and electrical conductivity measurement. The thermodynamic parameters of micellization were evaluated from electrical conductivity measurements at temperatures ranging from 293 to 313 K. The aggregation behavior of these synthesized gemini surfactants in water were investigated using dynamic light scattering and transmission electron microscopy. Further, the antimicrobial activities of these synthesized gemini surfactants against both Gram-positive and Gram-negative bacteria were also investigated.
- Zhu, Hai-Lin,Hu, Zhi-Yong,Ma, Xue-Mei,Wang, Jian-Long,Cao, Duan-Lin
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- Synthesis, surface activity and thermodynamic properties of cationic gemini surfactants with diester and rigid spacers
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A group of cationic gemini surfactants with diester and rigid spacers, 12-Ph-12, 14-Ph-14, 16-Ph-16, were synthesized and confirmed by IR, 1H NMR and elemental analysis. The surface parameters of the synthesized gemini surfactants including: the critical micelle concentration (CMC), the surface tension value at CMC (γCMC), effectiveness (πCMC), efficiency (pC20), maximum surface excess (Γmax) and minimum surface area (Amin), were obtained from surface tension measurements. These gemini surfactants showed higher surface activity than the traditional monomeric surfactants. The thermodynamic parameters of micellization process from conductivity measurements showed that the micellization was a spontaneous and exothermic process in environment, and the micellization process becomes less favorable with the decrease of alkyl chain length and increase in temperature. The micropolarity was evaluated from steady fluorescence spectra, and the dye solubilization was investigated by using UV–visible spectroscopy. The results revealed that the micropolarity of surfactant micelles is very low and these gemini surfactants can really enhance the solubility of water insoluble dyes.
- Zhang, Ting,Cao, Xianfei,Wang, Xuchun,Song, Changchun
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- Synthesis, characterization and study of mesomorphic behavior of new bent and linear core compounds containing heterocyclic rings
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The article presents the synthesis and liquid crystalline properties of some of new bent and linear core compounds containing a 1,3,4-oxadiazole, piperazine and thiazolidin-4-one rings as a central core. The new synthesized compounds were characterized by elemental analysis and FTIR, 1HNMR and mass spectroscopy). The liquid crystalline properties were studied by polarized optical microscopy and differential scanning calorimetry. All Schiff bases compounds with 1,3,4-oxadiazole and piprzaine ring in central core presented liquid crystalline properties. The liquid crystallinity of compounds containing 1,3,4-oxadiazole and thiazolidin-4-one rings as a central core were found depending on the type of terminal substituents.
- Al-Dujaili, Ammar H.,Karam, Nisreen H.,Shanshal, Alaa K.
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- HOCl responsive lanthanide complexes using hydroquinone caging units
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Redox biology is still looking for tools to monitor redox potential in cellular biology and, despite a large and sustained effort, reliable molecular probes have yet to emerge. In contrast, molecular probes for reactive oxygen and nitrogen have been widel
- Del Giorgio, Elena,S?rensen, Thomas Just
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- A linking group containing double ester bis-quaternary ammonium salt and its application as fungicide
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The present invention discloses a novel bis-quaternary ammonium salt compound with linking groups that contain diester groups. The bis-quaternary ammonium salt compound with linking groups that contain diester groups structurally comprises an ester group, and is environmentally friendly and easily degradable, and simple in preparation process. Compared to the commonly used quaternary ammonium bactericide, the bis-quaternary ammonium salt compound with linking groups that contain diester groups in the present invention has high surface activity, higher bactericidal activity, and less consumption. The structural formula of the compound is shown in the specification.
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Paragraph 0049; 0051-0052; 0076; 0078-0079
(2017/11/27)
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- Environmentally friendly methods for syntheses of new aromatic bisesters
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Two environmentally friendly methods, one in liquid and the other in solid phase, for preparation of phenyl bisesters (bearing alkylating groups) under microwave (MW) irradiation are presented. The MW remarkably enhanced the rate of acceleration for ester
- Zbancioc, Gheorghita N.,Zbancioc, Ana Maria V.,Mangalagiu, Ionel I.
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experimental part
p. 2201 - 2208
(2010/09/30)
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- Microwave-assisted synthesis of aromatic bis-esters in liquid phase
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A fast, general, environmentally friendly, and facile method for preparation of phenyl bis-esters under microwave irradiation in liquid phase is presented. Selective reaction pathways in order to get phenyl bis-esters only or phenyl monoesters only have b
- Zbancioc, Gheorghita N.,Zbancioc, Ana Maria V.,Mangalagiu, Ionel I.
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experimental part
p. 117 - 122
(2011/08/05)
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- CONTROLLED RELEASE OF BIOLOGICALLY ACTIVE COMPOUNDS
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The present invention relates to biodegradable polymers (e.g., polyesters and polyester amides) derived from functionalized biologically active compounds that can provide site specific delivery of bioactive compounds upon biodegradation in a controlled manner.
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