A simple and direct method for preparation of N-substituted spirocyclic dieSter of □-amino phosphonic acid (4) in high yield is introduced. The reaction consists of the threecomponent reachon of phenylurea (1), an ar...A simple and direct method for preparation of N-substituted spirocyclic dieSter of □-amino phosphonic acid (4) in high yield is introduced. The reaction consists of the threecomponent reachon of phenylurea (1), an aromatic aldehyde (2), and 3,9-dichloro-2,4,8,10-tetraoxa- 3, 9 -diphosphaspiro [5,5] undecane (3) in anhydrous benzene.展开更多
Three new cationic polymerizable surfactants are synthesized by the reaction of alkylmaleic hemiester with glycidyltrimethylammonium chloride. Their structures are confirmed by H-1 NMR, IR and elements analysis. The v...Three new cationic polymerizable surfactants are synthesized by the reaction of alkylmaleic hemiester with glycidyltrimethylammonium chloride. Their structures are confirmed by H-1 NMR, IR and elements analysis. The values of CMC and gamma (CMC) of these surfactants have been measured. One can obtain nearly monodisperse polystyrene latex by emulsion polymerization using the polymerizable surfactant.展开更多
Using methanol-water mixtures as the mobile phase, the chromatographic retention parameters k' and Rf were determined by reversed-phase high-performance liquid chromatography (RP-HPLC) and reversed-phase high-perf...Using methanol-water mixtures as the mobile phase, the chromatographic retention parameters k' and Rf were determined by reversed-phase high-performance liquid chromatography (RP-HPLC) and reversed-phase high-performance thin-layer chromatography (RP-HPTLC) for N-(benzothiazol-2-yl)-α-amino alkyl phosphoric diesters and the correlation with lipophilicity parameter (Clog P) was established. Log Kw values obtained from RP-HPLC and Rm values obtained from RP-HPTLC can be used to evaluate the lipophilicity of this kind of compounds. Chromatographic method is a good alternative for lipophilicity measurement.展开更多
In order to provide a new way for waste cooking oil(WCO) resource utilization, several diester derivatives were obtained from WCO through a three-step chemical modifications, viz.: transesterification, epoxidation and...In order to provide a new way for waste cooking oil(WCO) resource utilization, several diester derivatives were obtained from WCO through a three-step chemical modifications, viz.: transesterification, epoxidation and oxirane ring opening with carboxylic acids. The effects of the chain length of side chain groups on the viscosity, acid value, low temperature fluidity, thermo-oxidative stability, tribological properties and surface tension of diester derivatives were investigated. The results showed that increasing the chain length of side chain groups had a positive influence on the viscosity, viscosity index, acid value, pour point, friction coefficient and wear scar diameter along with a negative influence on the oxidation onset temperature, volatile loss, insoluble deposit, maximum non-seizure load and surface tension. These diester derivatives exhibited improved physicochemical and tribological properties that make themselves promising environmentally friendly biolubricant basestocks.展开更多
Transformations of di-n-butyl phthalate(DBP) and di(2-ethylhexyl) phthalate(DEHP) have been investigated in anaerobic/anoxic/oxic(A/A/O) leachate treatment processes. Although the DBP removal processes are different w...Transformations of di-n-butyl phthalate(DBP) and di(2-ethylhexyl) phthalate(DEHP) have been investigated in anaerobic/anoxic/oxic(A/A/O) leachate treatment processes. Although the DBP removal processes are different when the DBP initial concentration is different, the overall system DBP removal efficiencies are high(N 94%).DEHP is much more difficult to remove than DBP. The removal efficiency of DEHP is approximately 75%–78%.The results of mass balance calculations indicate that approximately 33.7%–50.7% of the DBP is degraded by the activated sludge, 48.9%–64.9% accumulates in the system, and 0.4%–1.4% is contained in the final effluent. Approximately 15.0%–19.0% of the DEHP is degraded by activated microcosms, 75.8%–79.0% accumulates in the system, and 5.2%–6.0% is contained in the final effluent. Biodegradation and adsorption to the activated sludge are the main mechanisms for DBP removal and adsorption to the activated sludge is the main mechanism for DEHP removal. The different removal mechanisms of the two PAEs may be related to their different molecular structures. However, PAEs are not really removed when they adsorb onto the sludge. Therefore, methods for decreasing PAEs adsorption and increasing the biodegradation efficiencies of the leachate treatment processes should be further investigated.展开更多
The kinetic study on the hydrolysis reaction of bis（4-nitrophenyl） phosphate （BNPP） catalyzed by Tb-BDBPH system（2：1） was carried out in 50% ethanol solution （pH 7.0-10.0） at 35℃ with I=0.10NaNO3. The second...The kinetic study on the hydrolysis reaction of bis（4-nitrophenyl） phosphate （BNPP） catalyzed by Tb-BDBPH system（2：1） was carried out in 50% ethanol solution （pH 7.0-10.0） at 35℃ with I=0.10NaNO3. The second-order rate constant kBNPP, 2.3×10.3 （mol^-1L S^-1）, was determined. The dinuclear monohydroxo species, L-2Tb-OH, is kinetically mainly active species. The hydrolysis rate of BNPP by the complex is increased almost 2.6 million-fold compared with the background hydroxide rate at the same condition.展开更多
Symmetric, diesters of cis- or trans- bicyclo[2,2,1]hept-5-ene-2,3-dicarboxylate were prepared by aqueous Diels-Alder reaction of cyclopentadiene with symmetric diester of fumarate or maleate.
Docosahexaenoic acid-acylated astaxanthin(DHA-AST)esters exhibit distinct bioactivities in improving brain function.However,the digestion and absorption characteristics of DHA-AST esters in vivo are unclear,thereby re...Docosahexaenoic acid-acylated astaxanthin(DHA-AST)esters exhibit distinct bioactivities in improving brain function.However,the digestion and absorption characteristics of DHA-AST esters in vivo are unclear,thereby restricting the molecular mechanism analysis of their superior activities.This study compared the digestion and absorption characteristics of DHA-AST monoester and diester by determining the levels of AST and DHA in the serum,liver,small intestinal content and wall,and feces at different time points after a single-dose oral administration of the esters.After oral gavage with 2 mg AST equivalent of the DHA-AST monoester and diester for 18 h,the excretion rates were approximately 51%and 84%,respectively.This result indicates that DHA-AST monoester was better than diester for the absorption of AST.The results in serum,liver,and small intestinal content and wall also agreed with this finding.Moreover,the excretion rates of DHA in the feces at 24 h in the DHA-AST monoester and diester groups were approximately 40%and 36%after gavage with 5 mg DHA equivalent,respectively.This result indicates that DHA-AST diester exhibited a better tendency than monoester for the absorption of DHA.Interestingly,the results in the liver and small intestinal wall showed an apparent difference,indicating that DHA-AST diester was better than monoester for the absorption of DHA.These findings provide a scientific basis for the molecular mechanism analysis and utilization of DHA-AST monoester and diester as functional ingredients.展开更多
文摘A simple and direct method for preparation of N-substituted spirocyclic dieSter of □-amino phosphonic acid (4) in high yield is introduced. The reaction consists of the threecomponent reachon of phenylurea (1), an aromatic aldehyde (2), and 3,9-dichloro-2,4,8,10-tetraoxa- 3, 9 -diphosphaspiro [5,5] undecane (3) in anhydrous benzene.
基金the National Natural Sciences Foundation of China (29903006) and National Microgravity Key Laboratory, Chinese Academy of Scie
文摘Three new cationic polymerizable surfactants are synthesized by the reaction of alkylmaleic hemiester with glycidyltrimethylammonium chloride. Their structures are confirmed by H-1 NMR, IR and elements analysis. The values of CMC and gamma (CMC) of these surfactants have been measured. One can obtain nearly monodisperse polystyrene latex by emulsion polymerization using the polymerizable surfactant.
基金Project supported by the Fund of State Key Laboratory of Elemento-Organic Chemistry, Nankai University
文摘Using methanol-water mixtures as the mobile phase, the chromatographic retention parameters k' and Rf were determined by reversed-phase high-performance liquid chromatography (RP-HPLC) and reversed-phase high-performance thin-layer chromatography (RP-HPTLC) for N-(benzothiazol-2-yl)-α-amino alkyl phosphoric diesters and the correlation with lipophilicity parameter (Clog P) was established. Log Kw values obtained from RP-HPLC and Rm values obtained from RP-HPTLC can be used to evaluate the lipophilicity of this kind of compounds. Chromatographic method is a good alternative for lipophilicity measurement.
基金the financial support from the Natural Science Foundation of Chongqing(Project No.cstc2014jcyj A90013)
文摘In order to provide a new way for waste cooking oil(WCO) resource utilization, several diester derivatives were obtained from WCO through a three-step chemical modifications, viz.: transesterification, epoxidation and oxirane ring opening with carboxylic acids. The effects of the chain length of side chain groups on the viscosity, acid value, low temperature fluidity, thermo-oxidative stability, tribological properties and surface tension of diester derivatives were investigated. The results showed that increasing the chain length of side chain groups had a positive influence on the viscosity, viscosity index, acid value, pour point, friction coefficient and wear scar diameter along with a negative influence on the oxidation onset temperature, volatile loss, insoluble deposit, maximum non-seizure load and surface tension. These diester derivatives exhibited improved physicochemical and tribological properties that make themselves promising environmentally friendly biolubricant basestocks.
基金funded by the National Natural Science Foundation of China(51678531,51878617).
文摘Transformations of di-n-butyl phthalate(DBP) and di(2-ethylhexyl) phthalate(DEHP) have been investigated in anaerobic/anoxic/oxic(A/A/O) leachate treatment processes. Although the DBP removal processes are different when the DBP initial concentration is different, the overall system DBP removal efficiencies are high(N 94%).DEHP is much more difficult to remove than DBP. The removal efficiency of DEHP is approximately 75%–78%.The results of mass balance calculations indicate that approximately 33.7%–50.7% of the DBP is degraded by the activated sludge, 48.9%–64.9% accumulates in the system, and 0.4%–1.4% is contained in the final effluent. Approximately 15.0%–19.0% of the DEHP is degraded by activated microcosms, 75.8%–79.0% accumulates in the system, and 5.2%–6.0% is contained in the final effluent. Biodegradation and adsorption to the activated sludge are the main mechanisms for DBP removal and adsorption to the activated sludge is the main mechanism for DEHP removal. The different removal mechanisms of the two PAEs may be related to their different molecular structures. However, PAEs are not really removed when they adsorb onto the sludge. Therefore, methods for decreasing PAEs adsorption and increasing the biodegradation efficiencies of the leachate treatment processes should be further investigated.
文摘The kinetic study on the hydrolysis reaction of bis（4-nitrophenyl） phosphate （BNPP） catalyzed by Tb-BDBPH system（2：1） was carried out in 50% ethanol solution （pH 7.0-10.0） at 35℃ with I=0.10NaNO3. The second-order rate constant kBNPP, 2.3×10.3 （mol^-1L S^-1）, was determined. The dinuclear monohydroxo species, L-2Tb-OH, is kinetically mainly active species. The hydrolysis rate of BNPP by the complex is increased almost 2.6 million-fold compared with the background hydroxide rate at the same condition.
文摘Symmetric, diesters of cis- or trans- bicyclo[2,2,1]hept-5-ene-2,3-dicarboxylate were prepared by aqueous Diels-Alder reaction of cyclopentadiene with symmetric diester of fumarate or maleate.
基金The work was supported by the National Key R&D Program of China(No.2018YFD0901103)the National Natural Science Foundation of China(Nos.31901688 and 31571864)+1 种基金the Natural Science Youth Foundation of Shandong Province(Nos.ZR2019QC004 and ZR2020QC236)the Laboratory for Marine Drugs and Bioproducts of Pilot National Laboratory for Marine Science and Technology(Qingdao,No.LMDBKF201807).
文摘Docosahexaenoic acid-acylated astaxanthin(DHA-AST)esters exhibit distinct bioactivities in improving brain function.However,the digestion and absorption characteristics of DHA-AST esters in vivo are unclear,thereby restricting the molecular mechanism analysis of their superior activities.This study compared the digestion and absorption characteristics of DHA-AST monoester and diester by determining the levels of AST and DHA in the serum,liver,small intestinal content and wall,and feces at different time points after a single-dose oral administration of the esters.After oral gavage with 2 mg AST equivalent of the DHA-AST monoester and diester for 18 h,the excretion rates were approximately 51%and 84%,respectively.This result indicates that DHA-AST monoester was better than diester for the absorption of AST.The results in serum,liver,and small intestinal content and wall also agreed with this finding.Moreover,the excretion rates of DHA in the feces at 24 h in the DHA-AST monoester and diester groups were approximately 40%and 36%after gavage with 5 mg DHA equivalent,respectively.This result indicates that DHA-AST diester exhibited a better tendency than monoester for the absorption of DHA.Interestingly,the results in the liver and small intestinal wall showed an apparent difference,indicating that DHA-AST diester was better than monoester for the absorption of DHA.These findings provide a scientific basis for the molecular mechanism analysis and utilization of DHA-AST monoester and diester as functional ingredients.
