Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic netw...Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.展开更多
Under physiological conditions, γ-aminobutyric acid poorly crosses the blood-brain barrier. It is likely that a non-toxic derivative of γ-aminobutyric acid which enters the brain easily will have useful anticonvulsa...Under physiological conditions, γ-aminobutyric acid poorly crosses the blood-brain barrier. It is likely that a non-toxic derivative of γ-aminobutyric acid which enters the brain easily will have useful anticonvulsant activity. 16 derivatives of γ-aminobutyric acid with an imine link to a lipophilic carrier were prepared and tested for anticonvulsant activity; six compounds show anticonvulsant activity.展开更多
Background Dietary fat is important for energy provision and immune function of lactating sows and their progeny.However,knowledge on the impact of fat on mammary transcription of lipogenic genes,de novo fat synthesis...Background Dietary fat is important for energy provision and immune function of lactating sows and their progeny.However,knowledge on the impact of fat on mammary transcription of lipogenic genes,de novo fat synthesis,and milk fatty acid(FA)output is sparse in sows.This study aimed to evaluate impacts of dietary fat levels and FA composition on these traits in sows.Forty second-parity sows(Danish Landrace×Yorkshire)were assigned to 1 of 5 dietary treatments from d 108 of gestation until weaning(d 28 of lactation):low-fat control diet(3%added animal fat);or 1 of 4 high-fat diets with 8%added fat:coconut oil(CO),fish oil(FO),sunflower oil(SO),or 4%octanoic acid plus 4%FO(OFO).Three approaches were taken to estimate de novo milk fat synthesis from glucose and body fat.Results Daily intake of FA was lowest in low-fat sows within fat levels(P<0.01)and in OFO and FO sows within highfat diets(P<0.01).Daily milk outputs of fat,FA,energy,and FA-derived carbon reflected to a large extent the intake of those.On average,estimates for de novo fat synthesis were 82 or 194 g/d from glucose according to method 1 or 2 and 255 g de novo+mobilized FA/d according to method 3.The low-fat diet increased mammary FAS expression(P<0.05)and de novo fat synthesis(method 1;P=0.13)within fat levels.The OFO diet increased de novo fat synthesis(method 1;P<0.05)and numerically upregulated mammary FAS expression compared to the other high-fat diets.Across diets,a daily intake of 440 g digestible FA minimized milk fat originating from glucose and mobilized body fat.Conclusions Sows fed diets with low-fat or octanoic acid,through upregulating FAS expression,increased mammary de novo fat synthesis whereas the milk FA output remained low in sows fed the low-fat diet or high-fat OFO or FO diets,indicating that dietary FA intake,dietary fat level,and body fat mobilization in concert determine de novo fat synthesis,amount and profiles of FA in milk.展开更多
Background: Isoleucine(Ile) has been implicated in the regulation of energy homeostasis and adipogenesis.However,the impact of surplus dietary Ile intake on muscle lipogenesis remains unknown.The present study aimed t...Background: Isoleucine(Ile) has been implicated in the regulation of energy homeostasis and adipogenesis.However,the impact of surplus dietary Ile intake on muscle lipogenesis remains unknown.The present study aimed to investigate the impact of dietary supplementation of extra-Ile on lipogenesis,fatty acid profile and lipid accumulation in skeletal muscle in finishing pigs.Methods: Forty-eight barrows with initial body weight of 77.0 ± 0.1 kg were allotted to one of two groups and fed diets containing 0.39%,0.53% standardized ileal digestible(SID) Ile with six replicates per treatment and four pigs per replicate for 30 d.Results: Dietary Ile intake significantly improved the intramuscular fat(IMF) content and monounsaturated fatty acid(MUFA) concentration in the skeletal muscle(P < 0.05),and decreased the drip loss and shear force(P < 0.05) without influencing the growth performance of pigs(P > 0.05).Moreover,the phosphorylation of adenosine monophosphate activated protein kinase α(AMPKα) and acetyl coenzyme A carboxylase(ACC) proteins that monitor lipid metabolism were decreased in skeletal muscle of pigs offered extra-Ile diet(P < 0.05).The mRNA expression of adipose-specific genes adipocyte determination and differentiation factor 1(ADD1),fatty acid synthase(FAS),and stearoyl-CoA desaturase(SCD) were upregulated and the activity of SCD was increased as well(P < 0.05).Conclusions: Surplus dietary Ile intake could increase IMF accumulation and MUFA synthesis in skeletal muscle through depressing the phosphorylation of AMPKα-ACC and stimulating the expression and activity of SCD,and increasing the capability of lipogenesis in skeletal muscle.展开更多
Melatonin and gamma-aminobutyric acid(GABA) have been shown to regulate sleep. The nocturnal concentrations of melatonin, GABA and total antioxidants may relate to insomnia in stroke patients. In this prospective si...Melatonin and gamma-aminobutyric acid(GABA) have been shown to regulate sleep. The nocturnal concentrations of melatonin, GABA and total antioxidants may relate to insomnia in stroke patients. In this prospective single-center non-randomized controlled clinical trial performed in the China Rehabilitation Research Center, we analyzed the relationship of nocturnal concentrations of melatonin, GABA and total antioxidants with insomnia after stroke. Patients during rehabilitation of stroke were recruited and assigned to the insomnia group or non-insomnia group. Simultaneously, persons without stroke or insomnia served as normal controls. Each group contained 25 cases. The primary outcome was nocturnal concentrations of melatonin, GABA and total antioxidants in peripheral blood. The secondary outcomes were Pittsburgh Sleep Quality Index, Insomnia Severity Index, Epworth Sleepiness Scale, Fatigue Severity Scale, Morningness-Eveningness Questionnaire(Chinese version), and National Institute of Health Stroke Scale. The relationship of nocturnal concentrations of melatonin, GABA and total antioxidants with insomnia after stroke was analyzed and showed that they were lower in the insomnia group than in the non-insomnia group. The severity of stroke was higher in the insomnia group than in the non-insomnia group. Correlation analysis demonstrated that the nocturnal concentrations of melatonin and GABA were associated with insomnia after stroke. This trial was registered at Clinical Trials.gov, identifier: NCT03202121.展开更多
A series of retinoate and retinamide derivatives were designed, synthesized, and their anti-tumor activities were investigated in NB4 by MTT and flow cytometry assays (FCM). All compounds showed cytotoxicity, especi...A series of retinoate and retinamide derivatives were designed, synthesized, and their anti-tumor activities were investigated in NB4 by MTT and flow cytometry assays (FCM). All compounds showed cytotoxicity, especially compounds la and ld exhibited a higher cytotoxicity than other derivatives and all-trans rethaoic acid (ATRA). Furthermore, compound 1d could induce NB4 cell lines differentiation efficiently. O 2009 Fei Hu Chert. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
A 2-acrylamide-2-methyl propylene sodium sulfonic (AMPS)-modified polyacrylic acid superplasticizer was synthesized using aqueous solution polymerization with the major monomers including the self-made active macrom...A 2-acrylamide-2-methyl propylene sodium sulfonic (AMPS)-modified polyacrylic acid superplasticizer was synthesized using aqueous solution polymerization with the major monomers including the self-made active macromers polyethylene glycol mono-methyl ether acrylate acrylic (MPEGAA), acrylic acid (AA), AMPS, and sodium methyl allyl sulfonate (SMAS). The ratios of the monomers were determined using an orthogonal experiment. This research focused on the effects of the dosages of different macromers, the polymerization conditions, and the length of MPEGAA side chains on the properties of the AMPS-modified polyacrylic acid super-plasticizer. The best polymerization conditions of the AMPS-modified polyacrylic acid superplasticizer are when (n(MPEGAA):n(SMAS):n(AMPS):n(AA) equals 0.1:0.1:0.2:0.65, the molecular weight of monomethoxypolyethylene glycol is 1 200, the initiator ammonium persulfate accounts for 5% of the total mass of the polymerized monomers, the polymerization temperature is 80 ~C, and the reaction time is 4 h. The AMPS-modified polyacrylic acid superplasticizer synthesized in the best conditions exhibited excellent dispersivity and dispersion retainability. When the dosage ratio was 0.24%, the initial fluidity was 400 mm and the fluidity had nearly no loss after 1 h.展开更多
Novel ionic liquids with dual acidity, of which the cation contains Brφnsted acidity and anions contain Lewis acidity were synthesized. These ionic liquids obtained were identified by NMR, FF-IR, SDT and FAB-MS. Thei...Novel ionic liquids with dual acidity, of which the cation contains Brφnsted acidity and anions contain Lewis acidity were synthesized. These ionic liquids obtained were identified by NMR, FF-IR, SDT and FAB-MS. Their acidities were determined by pyridine probe on IR spectrography.展开更多
Synthesis of tetrahydrofuran and tetrahydropyran derivatives catalyzed by tungstophosphoric acid (H3PW12040) were conveniently performed with high yield from the corresponding unsaturated alcohols in ionic liquid. S...Synthesis of tetrahydrofuran and tetrahydropyran derivatives catalyzed by tungstophosphoric acid (H3PW12040) were conveniently performed with high yield from the corresponding unsaturated alcohols in ionic liquid. Sufuric acid (H2SO4), trifluoromathanesulfonic acid (TfOH) and p-toluenesulfonic acid (TsOH) were also explored for preparing these products in ionic liquid. The catalysts and ionic liquid can be easily recovered and reused.展开更多
A novel organotin complex [Ph3Sn(C2H5OH)(OCOC5H3NBr)SnPh3(OCOC5H3NBr)] has been synthesized by the reaction of 5-bromonicotinic acid with triphenyltin hydroxide in ethanol and characterized by elemental analysis...A novel organotin complex [Ph3Sn(C2H5OH)(OCOC5H3NBr)SnPh3(OCOC5H3NBr)] has been synthesized by the reaction of 5-bromonicotinic acid with triphenyltin hydroxide in ethanol and characterized by elemental analysis, IR and ^1H NMR. The crystal structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 15.564(2), b = 24.975(4), c = 12.2973(19)°A, β = 92.224(2)°, Z = 4, V = 4776.5(13)°A^3, Dc = 1.596 g/cm^3, μ(MoKα) = 2.765 mm^-1, F(000) = 2264, R = 0.0385 and wR = 0.0667. In the molecular structure of the title complex, the tin atoms are five-coordinated in a trigonal bipyramidal geometry.展开更多
Based on the fact that petroselinic acid showed good inhibitory activity(IC50 = 6.99μmol/L) against protein tyrosine phophatase 1B(PTP1B) in vitro,a series of novel N-(alkoxyphenyl)-aminocarbonylbenzoic acid de...Based on the fact that petroselinic acid showed good inhibitory activity(IC50 = 6.99μmol/L) against protein tyrosine phophatase 1B(PTP1B) in vitro,a series of novel N-(alkoxyphenyl)-aminocarbonylbenzoic acid derivatives were designed and synthesized.The results indicated that most of the derivatives showed more potent activities against PTP1B.Especially,compound 13 had obvious activity with an IC50 of 106 nmol/L in vitro.展开更多
Glycolic acid was polymerized under vacuum in the presence and absence of nano sized clay.The added clay catalyzed the condensation polymerization which can be confirmed by recording FTIR spectroscopy and intrinsic vi...Glycolic acid was polymerized under vacuum in the presence and absence of nano sized clay.The added clay catalyzed the condensation polymerization which can be confirmed by recording FTIR spectroscopy and intrinsic viscosity (Ⅳ)values.The relative intensity of C=O/CH is increased while increasing the amount of clay.DSC showed the appearance of multiple endotherms of poly(glycolic acid).TGA showed the percentage weight residue remain above 750℃for polymer-nano composite system was 21% and hence proved the fl...展开更多
The title complex [^n BuSn(O)O2C(OH)CPh2]6.2H2O has been synthesized by the reaction of n-BuSn(O)OH with benzilic acid in 1:1 molar radio and characterized by IR, ^1H NMR spectra and elemental analysis. The cry...The title complex [^n BuSn(O)O2C(OH)CPh2]6.2H2O has been synthesized by the reaction of n-BuSn(O)OH with benzilic acid in 1:1 molar radio and characterized by IR, ^1H NMR spectra and elemental analysis. The crystal structure was determined by X-ray diffraction. It crystallizes in triclinic, space group PI with a = 1.3543(2), b = 1.4593(2), c = 1.5293(2) nm, α = 102.075 (2),β = 115.571 (2), γ = 93.308(3)°, Z = 1, V = 2.6282(7) nm^3, Mr = 2550.21, Dc = 1.611 g/cm^3,μ = 1.477 mm^-1, F(000) = 1280, R = 0.0309 and wR = 0.0729. The structure shows a distorted octahedral configuration with six-coordination for the central tin atom.展开更多
Nine racemic homocamptothecin derivatives were synthesized and in vitro antitumor activities were evaluated by standard MTT method. The results showed that some of the compound had higher antitumor activity than irite...Nine racemic homocamptothecin derivatives were synthesized and in vitro antitumor activities were evaluated by standard MTT method. The results showed that some of the compound had higher antitumor activity than iritecan.展开更多
Novel Lewis acidic ionic liquids containing thionyl cations and chloroaluminate anions were obtained by one-pot synthesis for the first time. Their acidities were determined by acetonitrile probe on IR spectrography. ...Novel Lewis acidic ionic liquids containing thionyl cations and chloroaluminate anions were obtained by one-pot synthesis for the first time. Their acidities were determined by acetonitrile probe on IR spectrography. The ionic liquids were used as catalyst for Friedel-Crafts alkylation of benzene and 1-dodecene. The turnovers of l-dodecene were higher than 99%. Monoalkylbenzene selectivity was 98%, while the 2-substituent product selectivity was 45%.展开更多
Kaolinite was hydrothermally synthesized from alumina gel and silicate by dissolving alumina gel in oxalic acid before it was mixed with silicate, effects of the amount of addition on the species of synthetic products...Kaolinite was hydrothermally synthesized from alumina gel and silicate by dissolving alumina gel in oxalic acid before it was mixed with silicate, effects of the amount of addition on the species of synthetic products were discussed. The reaction product was characterized by X ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that analcite is the only phase of the reaction solution without oxalic acid, the proportion of kaolinite in product increases with the amount of addition, and kaolinite is the main species when the molar ratio of oxalic acid to alumina reaches 0.6∶1.0. This is because oxalic acid addition is beneficial to the formation of kaolinite through changing the coordination number of aluminium from four to six, while the mixture of alumina gel, before it was dissolved in oxalic acid with silicate interfered with the crystallization of kaolinite.展开更多
This paper proposes a novel method relating to the recycling of waste lead ash originated from procedure of lead alloy production.The spent lead ash was first disposed by acetic acid leaching system,where lead ash str...This paper proposes a novel method relating to the recycling of waste lead ash originated from procedure of lead alloy production.The spent lead ash was first disposed by acetic acid leaching system,where lead ash structure wrapping impurities would be destroyed.The synthesis of lead oxide products was conducted at a lower temperature of 90℃.The effect of molar ratio of CH3 COOH to lead content of the ash on leaching efficiency was studied through the acetic acid leaching system.The results demonstrate that 84.6%of lead could be obtained in the leaching solution,while merely 0.7%of Fe blend in solution within a leaching time of 120 min.In the stage of lead oxide synthesis from leaching solution,the yield of lead oxide products could reach up to 94.4%when the molar ratio of NaOH to lead in filtrate was 2.5.This novel green method could shed light on the reuse of lead from exhausted ash with a much more convenient and environmentally friendly procedure.展开更多
A synthetic method of porphyrins tailed with salicylic substituents is described. Reaction of bromoalkoxyphenyl porphyrin 1 with salicylic acid gave porphyrins 2~5. These new compounds were confirmed by 1H NMR, IR, ...A synthetic method of porphyrins tailed with salicylic substituents is described. Reaction of bromoalkoxyphenyl porphyrin 1 with salicylic acid gave porphyrins 2~5. These new compounds were confirmed by 1H NMR, IR, UV-vis, MS and elemental analysis, and observed their interaction with bovine serum albumin (BSA) in fluorescence spectrum.展开更多
1,5-Benzodiazepine derivatives have been synthesized by the condensation of o-phenylenediamines and ketones in the presence of boric acid as catalyst under mild conditions. This method is simple, environmentally benig...1,5-Benzodiazepine derivatives have been synthesized by the condensation of o-phenylenediamines and ketones in the presence of boric acid as catalyst under mild conditions. This method is simple, environmentally benign and high yielding. ?2009 Chun Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
基金The authors are grateful for the financial support from National Natural Science Foundation of China(32001728).
文摘Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.
文摘Under physiological conditions, γ-aminobutyric acid poorly crosses the blood-brain barrier. It is likely that a non-toxic derivative of γ-aminobutyric acid which enters the brain easily will have useful anticonvulsant activity. 16 derivatives of γ-aminobutyric acid with an imine link to a lipophilic carrier were prepared and tested for anticonvulsant activity; six compounds show anticonvulsant activity.
基金Financially supported by the Danish Council for Independent Research,Technology and Production Sciences (Copenhagen K,Denmark)。
文摘Background Dietary fat is important for energy provision and immune function of lactating sows and their progeny.However,knowledge on the impact of fat on mammary transcription of lipogenic genes,de novo fat synthesis,and milk fatty acid(FA)output is sparse in sows.This study aimed to evaluate impacts of dietary fat levels and FA composition on these traits in sows.Forty second-parity sows(Danish Landrace×Yorkshire)were assigned to 1 of 5 dietary treatments from d 108 of gestation until weaning(d 28 of lactation):low-fat control diet(3%added animal fat);or 1 of 4 high-fat diets with 8%added fat:coconut oil(CO),fish oil(FO),sunflower oil(SO),or 4%octanoic acid plus 4%FO(OFO).Three approaches were taken to estimate de novo milk fat synthesis from glucose and body fat.Results Daily intake of FA was lowest in low-fat sows within fat levels(P<0.01)and in OFO and FO sows within highfat diets(P<0.01).Daily milk outputs of fat,FA,energy,and FA-derived carbon reflected to a large extent the intake of those.On average,estimates for de novo fat synthesis were 82 or 194 g/d from glucose according to method 1 or 2 and 255 g de novo+mobilized FA/d according to method 3.The low-fat diet increased mammary FAS expression(P<0.05)and de novo fat synthesis(method 1;P=0.13)within fat levels.The OFO diet increased de novo fat synthesis(method 1;P<0.05)and numerically upregulated mammary FAS expression compared to the other high-fat diets.Across diets,a daily intake of 440 g digestible FA minimized milk fat originating from glucose and mobilized body fat.Conclusions Sows fed diets with low-fat or octanoic acid,through upregulating FAS expression,increased mammary de novo fat synthesis whereas the milk FA output remained low in sows fed the low-fat diet or high-fat OFO or FO diets,indicating that dietary FA intake,dietary fat level,and body fat mobilization in concert determine de novo fat synthesis,amount and profiles of FA in milk.
基金supported by the National Key Research and Development Program of China(2018YFD0500402)the National Natural Science Foundation of China(No.31672431)the National Key Research and Development Program(2016YFD0700201)
文摘Background: Isoleucine(Ile) has been implicated in the regulation of energy homeostasis and adipogenesis.However,the impact of surplus dietary Ile intake on muscle lipogenesis remains unknown.The present study aimed to investigate the impact of dietary supplementation of extra-Ile on lipogenesis,fatty acid profile and lipid accumulation in skeletal muscle in finishing pigs.Methods: Forty-eight barrows with initial body weight of 77.0 ± 0.1 kg were allotted to one of two groups and fed diets containing 0.39%,0.53% standardized ileal digestible(SID) Ile with six replicates per treatment and four pigs per replicate for 30 d.Results: Dietary Ile intake significantly improved the intramuscular fat(IMF) content and monounsaturated fatty acid(MUFA) concentration in the skeletal muscle(P < 0.05),and decreased the drip loss and shear force(P < 0.05) without influencing the growth performance of pigs(P > 0.05).Moreover,the phosphorylation of adenosine monophosphate activated protein kinase α(AMPKα) and acetyl coenzyme A carboxylase(ACC) proteins that monitor lipid metabolism were decreased in skeletal muscle of pigs offered extra-Ile diet(P < 0.05).The mRNA expression of adipose-specific genes adipocyte determination and differentiation factor 1(ADD1),fatty acid synthase(FAS),and stearoyl-CoA desaturase(SCD) were upregulated and the activity of SCD was increased as well(P < 0.05).Conclusions: Surplus dietary Ile intake could increase IMF accumulation and MUFA synthesis in skeletal muscle through depressing the phosphorylation of AMPKα-ACC and stimulating the expression and activity of SCD,and increasing the capability of lipogenesis in skeletal muscle.
基金supported by the Optional Research Project of China Rehabilitation Research Center,No.2014-7the Sub-Project under National“Twelfth Five-Year”Plan for Science&Technology Support Project,No.2011BAI08B11
文摘Melatonin and gamma-aminobutyric acid(GABA) have been shown to regulate sleep. The nocturnal concentrations of melatonin, GABA and total antioxidants may relate to insomnia in stroke patients. In this prospective single-center non-randomized controlled clinical trial performed in the China Rehabilitation Research Center, we analyzed the relationship of nocturnal concentrations of melatonin, GABA and total antioxidants with insomnia after stroke. Patients during rehabilitation of stroke were recruited and assigned to the insomnia group or non-insomnia group. Simultaneously, persons without stroke or insomnia served as normal controls. Each group contained 25 cases. The primary outcome was nocturnal concentrations of melatonin, GABA and total antioxidants in peripheral blood. The secondary outcomes were Pittsburgh Sleep Quality Index, Insomnia Severity Index, Epworth Sleepiness Scale, Fatigue Severity Scale, Morningness-Eveningness Questionnaire(Chinese version), and National Institute of Health Stroke Scale. The relationship of nocturnal concentrations of melatonin, GABA and total antioxidants with insomnia after stroke was analyzed and showed that they were lower in the insomnia group than in the non-insomnia group. The severity of stroke was higher in the insomnia group than in the non-insomnia group. Correlation analysis demonstrated that the nocturnal concentrations of melatonin and GABA were associated with insomnia after stroke. This trial was registered at Clinical Trials.gov, identifier: NCT03202121.
文摘A series of retinoate and retinamide derivatives were designed, synthesized, and their anti-tumor activities were investigated in NB4 by MTT and flow cytometry assays (FCM). All compounds showed cytotoxicity, especially compounds la and ld exhibited a higher cytotoxicity than other derivatives and all-trans rethaoic acid (ATRA). Furthermore, compound 1d could induce NB4 cell lines differentiation efficiently. O 2009 Fei Hu Chert. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
基金Funded by Fujian Education Department(Nos.JA11329,JA12412)Quanzhou (Fujian) Technology Research and Development Program(No.2010G7)
文摘A 2-acrylamide-2-methyl propylene sodium sulfonic (AMPS)-modified polyacrylic acid superplasticizer was synthesized using aqueous solution polymerization with the major monomers including the self-made active macromers polyethylene glycol mono-methyl ether acrylate acrylic (MPEGAA), acrylic acid (AA), AMPS, and sodium methyl allyl sulfonate (SMAS). The ratios of the monomers were determined using an orthogonal experiment. This research focused on the effects of the dosages of different macromers, the polymerization conditions, and the length of MPEGAA side chains on the properties of the AMPS-modified polyacrylic acid super-plasticizer. The best polymerization conditions of the AMPS-modified polyacrylic acid superplasticizer are when (n(MPEGAA):n(SMAS):n(AMPS):n(AA) equals 0.1:0.1:0.2:0.65, the molecular weight of monomethoxypolyethylene glycol is 1 200, the initiator ammonium persulfate accounts for 5% of the total mass of the polymerized monomers, the polymerization temperature is 80 ~C, and the reaction time is 4 h. The AMPS-modified polyacrylic acid superplasticizer synthesized in the best conditions exhibited excellent dispersivity and dispersion retainability. When the dosage ratio was 0.24%, the initial fluidity was 400 mm and the fluidity had nearly no loss after 1 h.
基金the‘973’Program of the Chinese Ministry of Science and Technology(G-2000048002).
文摘Novel ionic liquids with dual acidity, of which the cation contains Brφnsted acidity and anions contain Lewis acidity were synthesized. These ionic liquids obtained were identified by NMR, FF-IR, SDT and FAB-MS. Their acidities were determined by pyridine probe on IR spectrography.
文摘Synthesis of tetrahydrofuran and tetrahydropyran derivatives catalyzed by tungstophosphoric acid (H3PW12040) were conveniently performed with high yield from the corresponding unsaturated alcohols in ionic liquid. Sufuric acid (H2SO4), trifluoromathanesulfonic acid (TfOH) and p-toluenesulfonic acid (TsOH) were also explored for preparing these products in ionic liquid. The catalysts and ionic liquid can be easily recovered and reused.
基金Project supported by the National Natural Science Foundation of China (No. 20271025) and Natural Science Foundation of Shandong Province (No. 2005ZX09)
文摘A novel organotin complex [Ph3Sn(C2H5OH)(OCOC5H3NBr)SnPh3(OCOC5H3NBr)] has been synthesized by the reaction of 5-bromonicotinic acid with triphenyltin hydroxide in ethanol and characterized by elemental analysis, IR and ^1H NMR. The crystal structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 15.564(2), b = 24.975(4), c = 12.2973(19)°A, β = 92.224(2)°, Z = 4, V = 4776.5(13)°A^3, Dc = 1.596 g/cm^3, μ(MoKα) = 2.765 mm^-1, F(000) = 2264, R = 0.0385 and wR = 0.0667. In the molecular structure of the title complex, the tin atoms are five-coordinated in a trigonal bipyramidal geometry.
基金Financial support was provided by the National Natural Science Funds for Young Scholar(No.30901841)the Research Fund for the Doctoral Program of Higher Education of China(No.200800231145)the Major Scientific and Technological Special Project for"Significant New Drugs Innovation"(No.2009ZX09301-003).
文摘Based on the fact that petroselinic acid showed good inhibitory activity(IC50 = 6.99μmol/L) against protein tyrosine phophatase 1B(PTP1B) in vitro,a series of novel N-(alkoxyphenyl)-aminocarbonylbenzoic acid derivatives were designed and synthesized.The results indicated that most of the derivatives showed more potent activities against PTP1B.Especially,compound 13 had obvious activity with an IC50 of 106 nmol/L in vitro.
文摘Glycolic acid was polymerized under vacuum in the presence and absence of nano sized clay.The added clay catalyzed the condensation polymerization which can be confirmed by recording FTIR spectroscopy and intrinsic viscosity (Ⅳ)values.The relative intensity of C=O/CH is increased while increasing the amount of clay.DSC showed the appearance of multiple endotherms of poly(glycolic acid).TGA showed the percentage weight residue remain above 750℃for polymer-nano composite system was 21% and hence proved the fl...
基金This work was supported by the Natural Science Foundation of Hunan Province(05JJ40015) and Project supported by Science Foundation of Hengyang Normal University of China (2004D16)
文摘The title complex [^n BuSn(O)O2C(OH)CPh2]6.2H2O has been synthesized by the reaction of n-BuSn(O)OH with benzilic acid in 1:1 molar radio and characterized by IR, ^1H NMR spectra and elemental analysis. The crystal structure was determined by X-ray diffraction. It crystallizes in triclinic, space group PI with a = 1.3543(2), b = 1.4593(2), c = 1.5293(2) nm, α = 102.075 (2),β = 115.571 (2), γ = 93.308(3)°, Z = 1, V = 2.6282(7) nm^3, Mr = 2550.21, Dc = 1.611 g/cm^3,μ = 1.477 mm^-1, F(000) = 1280, R = 0.0309 and wR = 0.0729. The structure shows a distorted octahedral configuration with six-coordination for the central tin atom.
基金the National Natural Science Foundation of China (No.30371689)Shanghai Major Program Science and Technology Foundation (No.064319009)Shanghai Leading Academic Discipline Project (No.B906).
文摘Nine racemic homocamptothecin derivatives were synthesized and in vitro antitumor activities were evaluated by standard MTT method. The results showed that some of the compound had higher antitumor activity than iritecan.
基金the grant from the National Natural Science Foundation of China (Key Program 20533010).
文摘Novel Lewis acidic ionic liquids containing thionyl cations and chloroaluminate anions were obtained by one-pot synthesis for the first time. Their acidities were determined by acetonitrile probe on IR spectrography. The ionic liquids were used as catalyst for Friedel-Crafts alkylation of benzene and 1-dodecene. The turnovers of l-dodecene were higher than 99%. Monoalkylbenzene selectivity was 98%, while the 2-substituent product selectivity was 45%.
文摘Kaolinite was hydrothermally synthesized from alumina gel and silicate by dissolving alumina gel in oxalic acid before it was mixed with silicate, effects of the amount of addition on the species of synthetic products were discussed. The reaction product was characterized by X ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that analcite is the only phase of the reaction solution without oxalic acid, the proportion of kaolinite in product increases with the amount of addition, and kaolinite is the main species when the molar ratio of oxalic acid to alumina reaches 0.6∶1.0. This is because oxalic acid addition is beneficial to the formation of kaolinite through changing the coordination number of aluminium from four to six, while the mixture of alumina gel, before it was dissolved in oxalic acid with silicate interfered with the crystallization of kaolinite.
基金Supported by the China Postdoctoral Science Foundation(2018M632799)the Education Department of Henan Province Science Research Program(18B610008,19A610010)the Henan province Key Research and Development and Promotion(182102311033)
文摘This paper proposes a novel method relating to the recycling of waste lead ash originated from procedure of lead alloy production.The spent lead ash was first disposed by acetic acid leaching system,where lead ash structure wrapping impurities would be destroyed.The synthesis of lead oxide products was conducted at a lower temperature of 90℃.The effect of molar ratio of CH3 COOH to lead content of the ash on leaching efficiency was studied through the acetic acid leaching system.The results demonstrate that 84.6%of lead could be obtained in the leaching solution,while merely 0.7%of Fe blend in solution within a leaching time of 120 min.In the stage of lead oxide synthesis from leaching solution,the yield of lead oxide products could reach up to 94.4%when the molar ratio of NaOH to lead in filtrate was 2.5.This novel green method could shed light on the reuse of lead from exhausted ash with a much more convenient and environmentally friendly procedure.
文摘A synthetic method of porphyrins tailed with salicylic substituents is described. Reaction of bromoalkoxyphenyl porphyrin 1 with salicylic acid gave porphyrins 2~5. These new compounds were confirmed by 1H NMR, IR, UV-vis, MS and elemental analysis, and observed their interaction with bovine serum albumin (BSA) in fluorescence spectrum.
文摘1,5-Benzodiazepine derivatives have been synthesized by the condensation of o-phenylenediamines and ketones in the presence of boric acid as catalyst under mild conditions. This method is simple, environmentally benign and high yielding. ?2009 Chun Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
基金Financial Supported by The G&P Foundation for Cancer Researchby Scientific Research Foundation for the Excellent Young Teacher from State Education Ministry(2002)by Natural Science Foundation of Liaoning Province(No.20022017)are gratefully acknowledged.