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2012 Volume 23 Issue 1
2012, 23(1): 1-4
doi: 10.1016/j.cclet.2011.09.016
Abstract:
Several imidazolium ionic liquid (IL)-supported sulfonic acids with different anions,[C3SO3Hmim]HSO4,[C3SO3Hmim]BF4,[C3SO3Hmim]PF6, and[C3SO3Hmim]CF3SO3, were synthesized and applied as catalysts for esterification reaction of benzoic acid. The experimental results indicate that imidazolium IL-supported sulfonic acid containing anion of HSO4- shows the best catalytic activity. Only when less[C3SO3Hmim]HSO4 (0.3 equiv.) applied, was the product obtained with high yield of 97%. Furthermore, the produced esters could be separated by decantation, and the catalyst could be reused after the removal of water.
Several imidazolium ionic liquid (IL)-supported sulfonic acids with different anions,[C3SO3Hmim]HSO4,[C3SO3Hmim]BF4,[C3SO3Hmim]PF6, and[C3SO3Hmim]CF3SO3, were synthesized and applied as catalysts for esterification reaction of benzoic acid. The experimental results indicate that imidazolium IL-supported sulfonic acid containing anion of HSO4- shows the best catalytic activity. Only when less[C3SO3Hmim]HSO4 (0.3 equiv.) applied, was the product obtained with high yield of 97%. Furthermore, the produced esters could be separated by decantation, and the catalyst could be reused after the removal of water.
2012, 23(1): 5-8
doi: 10.1016/j.cclet.2011.10.001
Abstract:
An effective route to S-vinylated and N-vinylated benzo[d]oxazole-2(3H)-thiones and benzo[d]thiazole-2(3H)-thiones is described via reaction of acetylenic esters and benzo[d]oxazole-2-thiol and benzo[d]thiazole-2-thiol in the presence of 15 mol% of isoquinoline.
An effective route to S-vinylated and N-vinylated benzo[d]oxazole-2(3H)-thiones and benzo[d]thiazole-2(3H)-thiones is described via reaction of acetylenic esters and benzo[d]oxazole-2-thiol and benzo[d]thiazole-2-thiol in the presence of 15 mol% of isoquinoline.
2012, 23(1): 9-12
doi: 10.1016/j.cclet.2011.10.002
Abstract:
In order to find novel antibacterial agents with superior antibacterial activity and overcoming multidrug resistance, a series of pleuromutilin derivatives with novel C(14) side chains were synthesized and evaluated for their in vitro antibacterial activities. The results of antibacterial acticities indicated that most of the derivatives showed potent activities against Gram-positive organisms. In particular, compound 10d exhibited the most potent inhibitory activity compared with pleuromutilin and linezoid, emerged as potential molecule for further investigation.
In order to find novel antibacterial agents with superior antibacterial activity and overcoming multidrug resistance, a series of pleuromutilin derivatives with novel C(14) side chains were synthesized and evaluated for their in vitro antibacterial activities. The results of antibacterial acticities indicated that most of the derivatives showed potent activities against Gram-positive organisms. In particular, compound 10d exhibited the most potent inhibitory activity compared with pleuromutilin and linezoid, emerged as potential molecule for further investigation.
2012, 23(1): 13-16
doi: 10.1016/j.cclet.2011.09.018
Abstract:
Cyclic phosphoric acid catalyzed one-pot, four component reactions of benzil, aldehydes, priminary amines and ammonium acetate in refluxing ethanol were developed, giving highly substituted imidazoles in excellent yield.
Cyclic phosphoric acid catalyzed one-pot, four component reactions of benzil, aldehydes, priminary amines and ammonium acetate in refluxing ethanol were developed, giving highly substituted imidazoles in excellent yield.
2012, 23(1): 17-20
doi: 10.1016/j.cclet.2011.10.003
Abstract:
A simple and efficient catalytic protocol for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes via the one-pot condensation of β-naphthol and aryl aldehydes using silicotungstic acid (H4[SiW12O40]) is reported. The present method offers several advantages such as high to excellent yields, short reaction times, recovery and reusability of catalyst, mild reaction conditions and easy workup procedures.
A simple and efficient catalytic protocol for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes via the one-pot condensation of β-naphthol and aryl aldehydes using silicotungstic acid (H4[SiW12O40]) is reported. The present method offers several advantages such as high to excellent yields, short reaction times, recovery and reusability of catalyst, mild reaction conditions and easy workup procedures.
2012, 23(1): 21-24
doi: 10.1016/j.cclet.2011.07.022
Abstract:
A new polymeric oxidizing reagent was prepared by supporting periodic acid on poly(1,4-phenylene-2,5-pyridine dicarboxyamide). This polymeric reagent was used for the selective oxidation of primary benzylic alcohols to the corresponding benzaldehydes in CH3CN at reflux conditions. Excellent selectivity was observed between primary benzyl alcohols and secondary ones as well as non-benzylic alcohols in the oxidation reactions. Allylic alcohols were also converted to the corresponding aldehydes with good yields.
A new polymeric oxidizing reagent was prepared by supporting periodic acid on poly(1,4-phenylene-2,5-pyridine dicarboxyamide). This polymeric reagent was used for the selective oxidation of primary benzylic alcohols to the corresponding benzaldehydes in CH3CN at reflux conditions. Excellent selectivity was observed between primary benzyl alcohols and secondary ones as well as non-benzylic alcohols in the oxidation reactions. Allylic alcohols were also converted to the corresponding aldehydes with good yields.
2012, 23(1): 25-28
doi: 10.1016/j.cclet.2011.07.023
Abstract:
Prednisolone succinate-glucosamine conjugate (PSG), a prodrug for prednisolone, was synthesized and confirmed by NMR and MS spectrum. The stabilities of the prodrug in PBS (pH 2.50, 5.00, 7.20, and 7.89) were studied. Cytotoxicity and uptake assay of the prodrug were perfomed on HK-2 and MDCK cell lines. The results showed that compared with prednisolone, the PSG not only did not increase the cytotoxicity but also improved the uptake to 2.2 times of prednisolone by the cells. Thus, it indicated that glucosamine might be a potential carrier for kidney-targeting delivery of prednisolone.
Prednisolone succinate-glucosamine conjugate (PSG), a prodrug for prednisolone, was synthesized and confirmed by NMR and MS spectrum. The stabilities of the prodrug in PBS (pH 2.50, 5.00, 7.20, and 7.89) were studied. Cytotoxicity and uptake assay of the prodrug were perfomed on HK-2 and MDCK cell lines. The results showed that compared with prednisolone, the PSG not only did not increase the cytotoxicity but also improved the uptake to 2.2 times of prednisolone by the cells. Thus, it indicated that glucosamine might be a potential carrier for kidney-targeting delivery of prednisolone.
2012, 23(1): 29-32
doi: 10.1016/j.cclet.2011.09.024
Abstract:
The carbonylation of phenyl bromide catalyzed by Co(OAc)2 has been investigated with PhCOPh as a sensitizer under visible light in the presence of basic additive. With strong base CH3ONa, PhCOOCH3 is produced in 70% yield with 100% selectivity, the similar results are also obtained with a stronger base (CH3)3CONa. However, with another strong base NaOH, the yield of the ester is only 40%. On the other hand, with weak base NaOAc or (n-C4H9)3N, phenyl bromide cannot be carbonylated. The results of carbonylation of the six substituted phenyl bromides suggest that the activities of o, m, p-BrC6H4CH3 are similar to phenyl bromide, while the activities of o, m, p-BrC6H4Cl are higher with the high yields (≥ 93%) of the corresponding chloro-esters. In addition, the relative position of bromine and chlorine or methyl on phenyl ring has little effect on the activity of the carbonylation.
The carbonylation of phenyl bromide catalyzed by Co(OAc)2 has been investigated with PhCOPh as a sensitizer under visible light in the presence of basic additive. With strong base CH3ONa, PhCOOCH3 is produced in 70% yield with 100% selectivity, the similar results are also obtained with a stronger base (CH3)3CONa. However, with another strong base NaOH, the yield of the ester is only 40%. On the other hand, with weak base NaOAc or (n-C4H9)3N, phenyl bromide cannot be carbonylated. The results of carbonylation of the six substituted phenyl bromides suggest that the activities of o, m, p-BrC6H4CH3 are similar to phenyl bromide, while the activities of o, m, p-BrC6H4Cl are higher with the high yields (≥ 93%) of the corresponding chloro-esters. In addition, the relative position of bromine and chlorine or methyl on phenyl ring has little effect on the activity of the carbonylation.
2012, 23(1): 33-36
doi: 10.1016/j.cclet.2011.10.004
Abstract:
The reaction of 2-formylpyrrole acetals with sodium alkoxide in alcohols at reflux temperature smoothly proceeded to generate corresponding transacetalization products in nearly quantitative yields. A plausible mechanism involving the formation of a highly reactive intermediate azafulvene species was proposed to explain the observed transformation.
The reaction of 2-formylpyrrole acetals with sodium alkoxide in alcohols at reflux temperature smoothly proceeded to generate corresponding transacetalization products in nearly quantitative yields. A plausible mechanism involving the formation of a highly reactive intermediate azafulvene species was proposed to explain the observed transformation.
2012, 23(1): 37-40
doi: 10.1016/j.cclet.2011.09.019
Abstract:
In this study, a novel series of chiral 1, 2-propanediol derivatives with different electron-donating and electron-withdrawing groups were synthesized and characterized by FT-IR, 1H NMR. The helical twisting properties of all the chiral dopants were investigated by doping the chiral dopants into a nematic liquid crystal host (SLC-1717). The results indicate that the donor-acceptor electron effect have a prominent influence on helical twisting property of the chiral nematic phase induced by the chiral dopants. Introducing electron-withdrawing groups into the terminal ends of chiral 1, 2-propanediol can decrease the absolute values of the helical twisting power. In addition, the helix inversion temperatures of the induced chiral nematic phase are variational with the change of terminal groups.
In this study, a novel series of chiral 1, 2-propanediol derivatives with different electron-donating and electron-withdrawing groups were synthesized and characterized by FT-IR, 1H NMR. The helical twisting properties of all the chiral dopants were investigated by doping the chiral dopants into a nematic liquid crystal host (SLC-1717). The results indicate that the donor-acceptor electron effect have a prominent influence on helical twisting property of the chiral nematic phase induced by the chiral dopants. Introducing electron-withdrawing groups into the terminal ends of chiral 1, 2-propanediol can decrease the absolute values of the helical twisting power. In addition, the helix inversion temperatures of the induced chiral nematic phase are variational with the change of terminal groups.
2012, 23(1): 41-44
doi: 10.1016/j.cclet.2011.10.005
Abstract:
For the first time, Au nanoparticles on graphene oxide (GO-AuNPs) were successfully fabricated without applying any additional reductants, just by the redox reaction between AuCl4-1 and GO. Their structure was characterized by transmission electron microscopy and x-ray powder diffraction. The results show that flower-like AuNPs were successfully dispersed on GO surface. Importantly, they showed a high catalytic activity for the Suzuki-Miyaura coupling reaction in an aqueous medium.
For the first time, Au nanoparticles on graphene oxide (GO-AuNPs) were successfully fabricated without applying any additional reductants, just by the redox reaction between AuCl4-1 and GO. Their structure was characterized by transmission electron microscopy and x-ray powder diffraction. The results show that flower-like AuNPs were successfully dispersed on GO surface. Importantly, they showed a high catalytic activity for the Suzuki-Miyaura coupling reaction in an aqueous medium.
2012, 23(1): 45-48
doi: 10.1016/j.cclet.2011.09.010
Abstract:
Three-component reaction of arylsulfonamides, dialkyl acetylenedicarboxylates, and ethyl chlorooxoacetate promoted by triphenylphosphine and triethylamine provides a sufficient route for the synthesis of dialkyl N-(arylsulfonyl)-4-ethoxy-5-oxo-2,5-dihydro-1H-pyrolle-2,3-dicarboxylates in good yields.
Three-component reaction of arylsulfonamides, dialkyl acetylenedicarboxylates, and ethyl chlorooxoacetate promoted by triphenylphosphine and triethylamine provides a sufficient route for the synthesis of dialkyl N-(arylsulfonyl)-4-ethoxy-5-oxo-2,5-dihydro-1H-pyrolle-2,3-dicarboxylates in good yields.
2012, 23(1): 49-52
doi: 10.1016/j.cclet.2011.10.006
Abstract:
The reaction between 2-aminobenzothiazole with dialkyl acetylenedicarboxylates in the presence of isocyanides, leads to functionalized azadienes in good yields.
The reaction between 2-aminobenzothiazole with dialkyl acetylenedicarboxylates in the presence of isocyanides, leads to functionalized azadienes in good yields.
2012, 23(1): 53-56
doi: 10.1016/j.cclet.2011.09.027
Abstract:
Liquid-phase epoxidation of styrene with atmospheric O2 was conducted over CoAPO-5 molecular sieves. The catalytic performance of CoAPO-5 can be significantly improved by alkali metal salt impregnated on it, and styrene conversion and selectivity to styrene oxide reached 85% and 69% respectively when CsCl was impregnated on it. The catalyst was recyclable and exhibited similar catalytic activity and selectivity even after three catalytic reaction cycles.
Liquid-phase epoxidation of styrene with atmospheric O2 was conducted over CoAPO-5 molecular sieves. The catalytic performance of CoAPO-5 can be significantly improved by alkali metal salt impregnated on it, and styrene conversion and selectivity to styrene oxide reached 85% and 69% respectively when CsCl was impregnated on it. The catalyst was recyclable and exhibited similar catalytic activity and selectivity even after three catalytic reaction cycles.
Synthesis and in vitro antimicrobial screening of new pyrano[4,3-b]pyrane derivatives of 1H-pyrazole
2012, 23(1): 57-60
doi: 10.1016/j.cclet.2011.09.012
Abstract:
A new series of pyrano[4,3-b]pyrane 4a-l bearing 1H-pyrazole has been synthesized by one pot base catalyzed cyclocondensation reaction of 1H-pyrazole-4-carbaldehyde 1a-l, malononitrile 2 and 4-hydroxy-6-methylpyrone 3. All the synthesized compounds were screened against six bacterial pathogens, namely B. subtilis, C. tetani, S. pneumoniae, S. typhi, V. cholerae, E. coli and antifungal activity against, two fungal pathogens, A. fumigatus and C. albicans using broth microdilution MIC method. Some of the compounds are found to be equipotent or more potent than that of commercial drugs, against most of employed strains.
A new series of pyrano[4,3-b]pyrane 4a-l bearing 1H-pyrazole has been synthesized by one pot base catalyzed cyclocondensation reaction of 1H-pyrazole-4-carbaldehyde 1a-l, malononitrile 2 and 4-hydroxy-6-methylpyrone 3. All the synthesized compounds were screened against six bacterial pathogens, namely B. subtilis, C. tetani, S. pneumoniae, S. typhi, V. cholerae, E. coli and antifungal activity against, two fungal pathogens, A. fumigatus and C. albicans using broth microdilution MIC method. Some of the compounds are found to be equipotent or more potent than that of commercial drugs, against most of employed strains.
2012, 23(1): 61-64
doi: 10.1016/j.cclet.2011.09.028
Abstract:
One-pot condensation of 2-aminothiophenol or 1,2-phenylenediamine with different aldehydes has been catalyzed by hexamethylenetetramine-bromine (HMTA-Bromine) as new, available and effective catalyst. 2-Arylbenzo-thiazoles and 2-aryl-benzimidazoles have been achieved in excellent yield and good purity.
One-pot condensation of 2-aminothiophenol or 1,2-phenylenediamine with different aldehydes has been catalyzed by hexamethylenetetramine-bromine (HMTA-Bromine) as new, available and effective catalyst. 2-Arylbenzo-thiazoles and 2-aryl-benzimidazoles have been achieved in excellent yield and good purity.
2012, 23(1): 65-68
doi: 10.1016/j.cclet.2011.10.008
Abstract:
Bismuth(Ⅲ) nitrate pentahydrate catalyzed the three-component condensation of β-naphthol, aldehydes and amines/urea under solvent-free conditions to afford the corresponding amidoalkyl naphthols in excellent yields.
Bismuth(Ⅲ) nitrate pentahydrate catalyzed the three-component condensation of β-naphthol, aldehydes and amines/urea under solvent-free conditions to afford the corresponding amidoalkyl naphthols in excellent yields.
2012, 23(1): 69-72
doi: 10.1016/j.cclet.2011.10.009
Abstract:
The reduction of diphenylacetylene with lithium naphthalenide produced two kinds of intermediates, 1 or 2, depending on the ratio of diphenylacetylene to lithium naphthalenide. A series of polyaryl substituted ethylene/diene derivatives were synthesized by reaction of electrophiles with the corresponding intermediates produced in-situ. All new compounds were fully characterized, and their single crystal structures were determined.
The reduction of diphenylacetylene with lithium naphthalenide produced two kinds of intermediates, 1 or 2, depending on the ratio of diphenylacetylene to lithium naphthalenide. A series of polyaryl substituted ethylene/diene derivatives were synthesized by reaction of electrophiles with the corresponding intermediates produced in-situ. All new compounds were fully characterized, and their single crystal structures were determined.
2012, 23(1): 73-76
doi: 10.1016/j.cclet.2011.09.021
Abstract:
A mild, efficient and eco-friendly process for the electrophilic nitration is described using N2O5 as a green nitrating agent in the presence of rare earth metal triflates[RE(OTf)3] under mild conditions.
A mild, efficient and eco-friendly process for the electrophilic nitration is described using N2O5 as a green nitrating agent in the presence of rare earth metal triflates[RE(OTf)3] under mild conditions.
Phosphine-free conversion of alcohols into alkyl thiocyanates using trichloroisocyanuric acid/NH4SCN
2012, 23(1): 77-80
doi: 10.1016/j.cclet.2011.09.022
Abstract:
A convenient and efficient phosphine-free procedure for the one-pot conversion of primary, secondary and tertiary alcohols into the corresponding alkyl thiocyanates or alkyl isothiocyanates is described using trichloroisocyanuric acid/NH4SCN.
A convenient and efficient phosphine-free procedure for the one-pot conversion of primary, secondary and tertiary alcohols into the corresponding alkyl thiocyanates or alkyl isothiocyanates is described using trichloroisocyanuric acid/NH4SCN.
2012, 23(1): 81-85
doi: 10.1016/j.cclet.2011.09.011
Abstract:
A simple and efficient protocol for the deprotection of dithioacetal, 1,3-dithianes and 1,3-dithiolanes has been developed using H2O2-SOCl2 reagent system. In addition to the absence of overoxidation products for oxidation-prone substrates, high chemoselectivity, the low cost and availability of the reagents, simplicity of the method, short reaction times, and excellent yields can also be considered as strong points for this method.
A simple and efficient protocol for the deprotection of dithioacetal, 1,3-dithianes and 1,3-dithiolanes has been developed using H2O2-SOCl2 reagent system. In addition to the absence of overoxidation products for oxidation-prone substrates, high chemoselectivity, the low cost and availability of the reagents, simplicity of the method, short reaction times, and excellent yields can also be considered as strong points for this method.
2012, 23(1): 86-88
doi: 10.1016/j.cclet.2011.09.015
Abstract:
Here we report a novel generation/collection operation mode of scanning electrochemical microscopy, in which a theta micropipette was employed to support two adjacent water/1,2-dichloroethane interfaces separated by the thin central glass wall:one acts as the generator while the other as the collector. The generation current, collection current andcollection efficiencywere enhanced significantly when the tip approached to an insulate substrate.
Here we report a novel generation/collection operation mode of scanning electrochemical microscopy, in which a theta micropipette was employed to support two adjacent water/1,2-dichloroethane interfaces separated by the thin central glass wall:one acts as the generator while the other as the collector. The generation current, collection current andcollection efficiencywere enhanced significantly when the tip approached to an insulate substrate.
2012, 23(1): 89-92
doi: 10.1016/j.cclet.2011.09.006
Abstract:
PAC subunit from avian influenza (H5N1) viral RNA polymerase was used in this work as a target in the screening for anti-influenza agents from licorice-derived compounds. As a result, 18β-glycyrrhetinic acid was suggested to be PAC ligand by flexible docking, and was then confirmed by relaxation-edited NMR. The result of ApG primer extension assay indicated that this PAC ligand can inhibit the polymerase activity, and thus may potentially be valuable as anti-influenza lead compound. This work validated the possibility of screening polymerase inhibitors by using PAC as a target, and provided a starting point for the further discovery of new anti-influenza drugs.
PAC subunit from avian influenza (H5N1) viral RNA polymerase was used in this work as a target in the screening for anti-influenza agents from licorice-derived compounds. As a result, 18β-glycyrrhetinic acid was suggested to be PAC ligand by flexible docking, and was then confirmed by relaxation-edited NMR. The result of ApG primer extension assay indicated that this PAC ligand can inhibit the polymerase activity, and thus may potentially be valuable as anti-influenza lead compound. This work validated the possibility of screening polymerase inhibitors by using PAC as a target, and provided a starting point for the further discovery of new anti-influenza drugs.
2012, 23(1): 93-96
doi: 10.1016/j.cclet.2011.09.009
Abstract:
The synthesis, characterization, and its response to metal ions of a novel thiourea N, N'-diethoxycarbonyl-N'', N'''-(1, 2-ethylidene) dithiourea was reported. The results show that this dithiourea with new structure can react with Cu2+ and Ni2+ separately, and has a best selectivity to Fe3+ ions. Bench-scale flotation tests were also carried out, verifying it has higher copper flotation recovery and better selectivity to sulfide ores containing Cu compared with universal collectors.
The synthesis, characterization, and its response to metal ions of a novel thiourea N, N'-diethoxycarbonyl-N'', N'''-(1, 2-ethylidene) dithiourea was reported. The results show that this dithiourea with new structure can react with Cu2+ and Ni2+ separately, and has a best selectivity to Fe3+ ions. Bench-scale flotation tests were also carried out, verifying it has higher copper flotation recovery and better selectivity to sulfide ores containing Cu compared with universal collectors.
2012, 23(1): 97-100
doi: 10.1016/j.cclet.2011.09.023
Abstract:
A new positively thermo-sensitive hydrogel was designed and synthesized by a condensation polymerization reaction of ethylenediaminetetraacetic dianhydride (EDTAD) and piperazine (PA) to give poly (ethylenediaminetetraacetic dianhydride-co-piperazine) (PEP). The obtained polymers' structure was characterized by FTIR and 13C NMR. The backbone of the polymer linked by amide bond and abundant of carboxyl groups as pendant group could form strong intermolecular and intramolecular hydrogen bond at lower temperature and dissociate at higher temperature, resulting in the polymer with thermo-sensitivity. The aqueous solution of PEP at lower temperature (< 20℃) showed micro-gel formation and transformed to transparent solution at higher temperature (> 40℃). Transition temperature shifted to higher value with the increasing of concentration. The hydrogel exhibited reversible phase transition and the transmittance change was not weakened by multiple temperature changes.
A new positively thermo-sensitive hydrogel was designed and synthesized by a condensation polymerization reaction of ethylenediaminetetraacetic dianhydride (EDTAD) and piperazine (PA) to give poly (ethylenediaminetetraacetic dianhydride-co-piperazine) (PEP). The obtained polymers' structure was characterized by FTIR and 13C NMR. The backbone of the polymer linked by amide bond and abundant of carboxyl groups as pendant group could form strong intermolecular and intramolecular hydrogen bond at lower temperature and dissociate at higher temperature, resulting in the polymer with thermo-sensitivity. The aqueous solution of PEP at lower temperature (< 20℃) showed micro-gel formation and transformed to transparent solution at higher temperature (> 40℃). Transition temperature shifted to higher value with the increasing of concentration. The hydrogel exhibited reversible phase transition and the transmittance change was not weakened by multiple temperature changes.
2012, 23(1): 101-104
doi: 10.1016/j.cclet.2011.09.013
Abstract:
Stripping dispersion hollow fiber liquid membrane system (SDHFLM) containing feed phase adding acetate buffer solution and dispersion solution with HNO3 solution as the stripping solution and membrane solution of 2-ethyl hexyl phosphoric acid-mono-2-ethylhexyl ester (PC-88A) dissolved in kerosene, has been studied for the extraction of Sm3+. Many factors including pH value, volume ratio of membrane solution to stripping solution (O/W) and carrier concentration on Sm3+ extraction were investigated. Experimental results indicate that the optimum extraction conditions of Sm3+ were obtained as that PC-88A concentration was 0.120 mol/L, and O/W was 1.00 in the dispersion phase, and pH value was 4.80 in the feed phase. When initial Sm3+ concentration was 1.20×10-4 mol/L, the extraction percentage of Sm3+ was up to 92.8% in 160 min.
Stripping dispersion hollow fiber liquid membrane system (SDHFLM) containing feed phase adding acetate buffer solution and dispersion solution with HNO3 solution as the stripping solution and membrane solution of 2-ethyl hexyl phosphoric acid-mono-2-ethylhexyl ester (PC-88A) dissolved in kerosene, has been studied for the extraction of Sm3+. Many factors including pH value, volume ratio of membrane solution to stripping solution (O/W) and carrier concentration on Sm3+ extraction were investigated. Experimental results indicate that the optimum extraction conditions of Sm3+ were obtained as that PC-88A concentration was 0.120 mol/L, and O/W was 1.00 in the dispersion phase, and pH value was 4.80 in the feed phase. When initial Sm3+ concentration was 1.20×10-4 mol/L, the extraction percentage of Sm3+ was up to 92.8% in 160 min.
2012, 23(1): 105-108
doi: 10.1016/j.cclet.2011.09.029
Abstract:
The graft copolymerization of acrylic acid (AA) onto polyethylene glycol terephthalate (PET) fiber initiated by benzoy peroxide (BPO) was carried out in heterogeneous media. Moreover, modification of the grafted PET fiber (PET-AA) was done by changing the carboxyl group into acylamino group through the reaction with dimethylamine. The modified chelating fiber (NDWJN1) was characterized using elementary analysis, SEM and FT-IR spectroscopy. Adsorption kinetic curves indicated that NDWJN1 could fast remove heavy metal ions and phytic acids from water effectively. Furthermore, batch kinetic studies indicated that heavy metal ions adsorbed to NDWJN1 could be fitted well by both pseudo-first-order and pseudo-second-order adsorption equations, but the intra-particle diffusion played a dominant role in the adsorption of phytic acids.
The graft copolymerization of acrylic acid (AA) onto polyethylene glycol terephthalate (PET) fiber initiated by benzoy peroxide (BPO) was carried out in heterogeneous media. Moreover, modification of the grafted PET fiber (PET-AA) was done by changing the carboxyl group into acylamino group through the reaction with dimethylamine. The modified chelating fiber (NDWJN1) was characterized using elementary analysis, SEM and FT-IR spectroscopy. Adsorption kinetic curves indicated that NDWJN1 could fast remove heavy metal ions and phytic acids from water effectively. Furthermore, batch kinetic studies indicated that heavy metal ions adsorbed to NDWJN1 could be fitted well by both pseudo-first-order and pseudo-second-order adsorption equations, but the intra-particle diffusion played a dominant role in the adsorption of phytic acids.
2012, 23(1): 109-112
doi: 10.1016/j.cclet.2011.10.010
Abstract:
To determine the concentrations of total oils, petroleum hydrocarbons, and animal and vegetable oils in water, the conventional analytical methods involve two scans as well as a step of magnesium silicate adsorption to remove the animal and vegetable oils in water samples. In this study, a novel analytical method was developed to determine the above oils in wastewater samples through just one scan-the concentration of animal and vegetable oils, and that of total oils were determined by measuring the absorbance of the > C=O bond in the peak area between 1750 cm-1 and 1735 cm-1, and of the C-H bond at 2930 -1, 2960 cm-1, and 3030 cm-1, respectively. The concentration of petroleum hydrocarbons was then calculated by subtracting the concentration of animal and vegetable oils from that of total oils. Compared with the well-known analytical method GB/T 16488-1996, the novel approach displayed similar accuracy in the quantitative determination of oils in wastewater samples, but significantly reduced material cost and operation time.
To determine the concentrations of total oils, petroleum hydrocarbons, and animal and vegetable oils in water, the conventional analytical methods involve two scans as well as a step of magnesium silicate adsorption to remove the animal and vegetable oils in water samples. In this study, a novel analytical method was developed to determine the above oils in wastewater samples through just one scan-the concentration of animal and vegetable oils, and that of total oils were determined by measuring the absorbance of the > C=O bond in the peak area between 1750 cm-1 and 1735 cm-1, and of the C-H bond at 2930 -1, 2960 cm-1, and 3030 cm-1, respectively. The concentration of petroleum hydrocarbons was then calculated by subtracting the concentration of animal and vegetable oils from that of total oils. Compared with the well-known analytical method GB/T 16488-1996, the novel approach displayed similar accuracy in the quantitative determination of oils in wastewater samples, but significantly reduced material cost and operation time.
2012, 23(1): 113-116
doi: 10.1016/j.cclet.2011.09.020
Abstract:
Mixed conducting perovskite oxide SrCo0.9Ta0.1O3-δ (SCT) is synthesized by solid-state reaction method. The activation in the initial stage of oxygen permeation through the SCT membrane is investigated. The results show that the activation in the initial stage of oxygen permeation has activate-memory, the first activation can only help to reduce active time of the next cycles, but it is helpless to increase the final oxygen permeation flux. XRD characterization shows that the imperfect perovskite phase structure is gradually improved and the crystal lattice has made some self-adjustment under the permeation conditions, therefore, the oxygen permeation flux of SCT disk membrane increases gradually and till it reaches a steady state.
Mixed conducting perovskite oxide SrCo0.9Ta0.1O3-δ (SCT) is synthesized by solid-state reaction method. The activation in the initial stage of oxygen permeation through the SCT membrane is investigated. The results show that the activation in the initial stage of oxygen permeation has activate-memory, the first activation can only help to reduce active time of the next cycles, but it is helpless to increase the final oxygen permeation flux. XRD characterization shows that the imperfect perovskite phase structure is gradually improved and the crystal lattice has made some self-adjustment under the permeation conditions, therefore, the oxygen permeation flux of SCT disk membrane increases gradually and till it reaches a steady state.
2012, 23(1): 117-120
doi: 10.1016/j.cclet.2011.09.026
Abstract:
A novel up-converting phosphor, NaxAl,yFx+3y/CaF2 (0.3 < x < 0.5, 0 < y < 0.1) composite, is prepared by a hydrothermal process at 180℃ and an annealing treatment at 500℃. X-ray diffraction (XRD) pattern indicates that NaxAlyFx+3y/CaF2 is a composite consisting of NaF, Na3AlF6, and CaF2. The up-conversion luminescence properties of this phosphor are investigated by fluorescence spectrometer. Results show that NaxAlyFx+3y/CaF2 exhibits visible-to-ultraviolet up-conversion luminescence properties. The emission peaks at 316 and 336 nm are observed when excited by 610 nm, the luminescence lifetime of the emissions is great than 18 ms, and the internal fluorescence quantum yield is 4.2%. Additionally, the luminescent mechanism of this phosphor is also mentioned.
A novel up-converting phosphor, NaxAl,yFx+3y/CaF2 (0.3 < x < 0.5, 0 < y < 0.1) composite, is prepared by a hydrothermal process at 180℃ and an annealing treatment at 500℃. X-ray diffraction (XRD) pattern indicates that NaxAlyFx+3y/CaF2 is a composite consisting of NaF, Na3AlF6, and CaF2. The up-conversion luminescence properties of this phosphor are investigated by fluorescence spectrometer. Results show that NaxAlyFx+3y/CaF2 exhibits visible-to-ultraviolet up-conversion luminescence properties. The emission peaks at 316 and 336 nm are observed when excited by 610 nm, the luminescence lifetime of the emissions is great than 18 ms, and the internal fluorescence quantum yield is 4.2%. Additionally, the luminescent mechanism of this phosphor is also mentioned.
2012, 23(1): 121-122
doi: 10.1016/j.cclet.2011.09.014
Abstract:
A new kind of asymmetrical ether diamine, 3, 4'-bis(4-aminophenoxy)benzophenone (BABP), was synthesized from the nucleophilic substitution reaction of 4-chloronitrobenzene and 3, 4'-dihydroxybenzophenone in the presence of potassium carbonate, followed by catalytic reduction with SnCl2·6H2O and concentrated hydrochloric acid. The prepared diamine was employed in the preparation of a novel polyimide containing asymmetrical diaryl ether segments via the polycondensation of it with BTDA by a two-step method. The resulting polyimide exhibits excellent solubility, film-forming capability and high thermal resistance.
A new kind of asymmetrical ether diamine, 3, 4'-bis(4-aminophenoxy)benzophenone (BABP), was synthesized from the nucleophilic substitution reaction of 4-chloronitrobenzene and 3, 4'-dihydroxybenzophenone in the presence of potassium carbonate, followed by catalytic reduction with SnCl2·6H2O and concentrated hydrochloric acid. The prepared diamine was employed in the preparation of a novel polyimide containing asymmetrical diaryl ether segments via the polycondensation of it with BTDA by a two-step method. The resulting polyimide exhibits excellent solubility, film-forming capability and high thermal resistance.
2012, 23(1): 123-126
doi: 10.1016/j.cclet.2011.10.007
Abstract:
A novel p-acetaminophen resin (named as GQ-1) was synthesized with chloromethylated polystyrene and p-acetaminophen. It can be used without any wetting process. The objective of this work was to study the adsorption performances for vanillin onto GQ-1 with two kinds of the hydrogen bond site of acetamino group and hydroxyl group. The results showed that the adsorption property of vanillin onto GQ-1 was superior to XAD-4, H103, NDA150, and NDA88. The adsorption capacity of vanillin onto GQ-1 is not greatly discrepant until the solution pH is higher than 5.31. The saturated adsorption quantity of vanillin was up to 141.32 mg/mL (wet resin) according to the dynamic adsorption and desorption experiments at 293 K. The resin could be regenerated by 7 BV ethanol.
A novel p-acetaminophen resin (named as GQ-1) was synthesized with chloromethylated polystyrene and p-acetaminophen. It can be used without any wetting process. The objective of this work was to study the adsorption performances for vanillin onto GQ-1 with two kinds of the hydrogen bond site of acetamino group and hydroxyl group. The results showed that the adsorption property of vanillin onto GQ-1 was superior to XAD-4, H103, NDA150, and NDA88. The adsorption capacity of vanillin onto GQ-1 is not greatly discrepant until the solution pH is higher than 5.31. The saturated adsorption quantity of vanillin was up to 141.32 mg/mL (wet resin) according to the dynamic adsorption and desorption experiments at 293 K. The resin could be regenerated by 7 BV ethanol.
