Three kinds of iron nanoparticles(FeNPs)were prepared via green route based on pomegranate(PG),green tea(GT),and mulberry(ML)extracts under ambient conditions.The obtained materials were characterized by scanning elec...Three kinds of iron nanoparticles(FeNPs)were prepared via green route based on pomegranate(PG),green tea(GT),and mulberry(ML)extracts under ambient conditions.The obtained materials were characterized by scanning electron microscopy(SEM),transmission electronic microscopy(TEM),X-ray energy-dispersive spectrometer(EDS),X-ray diffraction(XRD),fourier transform infrared spectroscopy(FTIR),and X-ray photoelectron spectroscopy(XPS)techniques.The experimental results show that FeNPs were in the form of amorphous iron(Ⅱ,Ⅲ)-polyphenol complex with different dispersity and morphologies.GT-Fe has the smallest size range of 25-35 nm,PG-Fe has a moderate size-distribution of 30-40 nm,while ML-Fe formed a tuberous net-type with a sheeting structure.PG-Fe displays the highest removal efficiency of 90.2%in 20 min towards cationic dye of malachite green(16.6%by ML-Fe and 69.3%by GT-Fe),which is attributed to its highest polyphenol content,lowest zeta potential,as well as the most Fe^(2+)on the surface of FeNPs.The removal mechanism was mainly induced by electrostatic adsorption based on pH and zeta potential tests.展开更多
A new environmental friendly catalyst H3PW12O40/PAn was prepared and identified by means of FT-IR,XRD,and TG/DTA.The optimum conditions have been found;that is,the mass ratio of PAn to H3PW12O40 is 1：1.5,the volume o...A new environmental friendly catalyst H3PW12O40/PAn was prepared and identified by means of FT-IR,XRD,and TG/DTA.The optimum conditions have been found;that is,the mass ratio of PAn to H3PW12O40 is 1：1.5,the volume of methanol is 20 mL,and the reflux reaction time is 3 h.The structural identity of Keggin units is preserved after the incorporation into polyaniline matrix.Catalytic activities of H3PW12O40/PAn in synthesizing 2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane,2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane,cyclohexanone ethylene ketal,cyclohexanone 1,2-propanediol ketal,butanone ethylene ketal,butanone 1,2-propanediol ketal,2-phenyl-1,3-dioxolane,4-methyl-2-phenyl-1,3-dioxolane,2-propyl-1,3-dioxolane,and 4-methyl-2-propyl-1,3-dioxolane were reported.It has been demon-strated that H3PW12O40/PAn is an excellent catalyst.Various factors concerned in these reactions were investigated.The optimum conditions are as follows：the molar ratio of aldehyde/ketone to glycol（r） is 1：1.5,the mass ratio of the catalyst used to the reactants is 0.6%,and the reaction time is 1.0 h.Under these conditions,the yield is as follows：2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane,69.0%;2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane,79.5%;cyclohexanone ethylene ketal,78.9%;cyclohexanone 1,2-propanediol ketal,85.3%;butanone ethylene ketal,56.9%;butanone 1,2-propanediol ketal,78.1%;2-phenyl-1,3-dioxolane,76.3%;4-methyl-2-phenyl-1,3-dioxolane,94.2%;2-propyl-1,3-dioxolane,70.7%;and 4-methyl-2-propyl-1,3-dioxolane,79.2%.展开更多
Catalytic activity of activated carbon supported tungstosilicic acidin synthesizing 2-methyl-2-ethoxycarbonylmethyl- 1,3-dioxolane, 2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane, cyclohexanone ethylene ketal, cycl...Catalytic activity of activated carbon supported tungstosilicic acidin synthesizing 2-methyl-2-ethoxycarbonylmethyl- 1,3-dioxolane, 2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane, cyclohexanone ethylene ketal, cyclohexanone 1,2-propa- nediol ketal, butanone ethylene ketal, butanone 1,2-propanediol ketal, 2-phenyl-1,3-dioxolane, 4-methyl-2-phenyl-1,3-dioxolane, 2-propyl-1,3-dioxolane, 4-methyl-2-propyl-1,3-dioxolane was reported. It has been demonstrated that activated carbon supported tungstosilicic acid is an excellent catalyst. Various factors involved in these reactions were investigated. The optimum conditions found were: molar ratio of aldehyde/ketone to glycol is 1/1.5, mass ratio of the catalyst used to the reactants is 1.0%, and reaction time is 1.0 h. Under these conditions, the yield of 2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane is 61.5%, of 2,4-dimethyl- 2-ethoxycarbonylmethyl-1,3-dioxolane is 69.1%, of cyclohexanone ethylene ketal is 74.6%, of cyclohexanone 1,2-propanediol ketal is 80.1%, of butanone ethylene ketal is 69.5%, of butanone 1,2-propanediol ketal is 78.5%, of 2-phenyl-1,3-dioxolane is 56.7%, of 4-methyl-2-phenyl-1,3-dioxolane is 86.2%, of 2-propyl-1,3-dioxolane is 87.5%, of 4-methyl-2-propyl-1,3-dioxolane is 87.9%.展开更多
SO4^2-/TiO2-MoO3, a novel solid superacid, has been prepared and its catalytic activity at different synthetic conditions was examined with esterification of n-butanoic acid and n-butyl alcohol as probing reaction.The...SO4^2-/TiO2-MoO3, a novel solid superacid, has been prepared and its catalytic activity at different synthetic conditions was examined with esterification of n-butanoic acid and n-butyl alcohol as probing reaction.The optimum conditions were also found, that is, the mass ratio of MoO3 used in the compound is 25%, the calcination temperature 450℃, and the soaked consistency of H2SO4 is 0.5mol.L^-1. Then it was applied in the catalytic synthesis of six similar important ketals and acetals as catalyst and revealed high catalytic activity. Under the condition that the molar ratio of aldehyde/ketone to glycol was 1:1.5, the mass ratio of the catalyst to the reactants was 0.5% and the reaction time 1.0 h, the yield of ketals and acetals reached up to 63.2%. The catalyst can be easily recovered and reused.展开更多
Twelve classes of acetals and ketals were synthesized from aldehyde/ketone and glycol using ZiSiW12O40/TiO2 as a novel eco-friendly catalyst. The physical characterizations were carried out by TG/DTA, FT-IR, XRD, and ...Twelve classes of acetals and ketals were synthesized from aldehyde/ketone and glycol using ZiSiW12O40/TiO2 as a novel eco-friendly catalyst. The physical characterizations were carried out by TG/DTA, FT-IR, XRD, and ^1H NMR spectra. The results indicated that the catalyst showed excellent catalytic activity for the condensation reactions. The yield of 12 classes of acetals and ketals reached 56.3%-96.3% under the typical reaction conditions （the molar ratio of aldehyde/ketone and glycol was 1：1.5, the quantity of catalyst was 0.5% of feed stock, the reaction time was 1.0 h, and the reaction temperature was 80-116℃）. The catalyst was easily recovered and reused to give almost the same yield of the product as that given by fresh TiSiW12O10/TiO2.展开更多
SO4^2- / TiO2-La2O3, a novel solid superacid, was prepared and its catalytic activities at different synthetic conditions are discussed with esterification of n-butanoic acid and n-butyl alcohol as probing reaction. T...SO4^2- / TiO2-La2O3, a novel solid superacid, was prepared and its catalytic activities at different synthetic conditions are discussed with esterification of n-butanoic acid and n-butyl alcohol as probing reaction. The optimum conditions have also been found, mole ratio of n（La^3＋）：n（Ti^4＋） is 1：34, the soaked consistency of H2SO4 is 0.8 tool/L, the soaked time of HESO4 is 24 h, the calcining temperature is 480 ℃, the calcining time is 3 h. Then it was applied in the catalytic synthesis often important ketals and acetals as catalyst and revealed high catalytic activity. Under these conditions on which the molar ratio of aldehyde/ketone to glycol is l： 1.5, the mass ratio of the catalyst used in the reactants is 0.5%, and the reaction time is 1.0 h, the yields of ketals and acetals can reach 41.4%-95.8%.展开更多
The title compound, [Cu（C6H4N2O4F）2（H2O）4].4（H2O） I, has been hydrothermally synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in monoclinic, space group P21/c w...The title compound, [Cu（C6H4N2O4F）2（H2O）4].4（H2O） I, has been hydrothermally synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in monoclinic, space group P21/c with a = 8.3041（17）, b = 12.045（2）, c = 11.077（2） A, β = 92.567（3）°, V= 1106.8（4） A^3, Mr = 581.89, Z= 2, Dc = 1.746 g/cm^3, F（000） = 598,μ（MoKa） = 1.090 mm^-1, the final R = 0.0296 and wR = 0.0806 for 3195 observed reflections with Ⅰ 〉 2σ（Ⅰ）. In the centrosymmetric compound I, each Cu（Ⅱ） ion is coordinated by six O atoms from two 5-fluorouracil-1-acetate anions and four water molecules, forming a six-coordinated octahedral environment. N-H…O and O-H…O hydrogen-bonding interactions are observed in the structure, leading to the formation of a three-dimensional network.展开更多
In order to enhance the electrogenerative leaching rate of chalcopyrite concentrate reasonably, the principle of generative process was applied to simultaneous leaching of chalcopyrite concentrate and MnO2. The result...In order to enhance the electrogenerative leaching rate of chalcopyrite concentrate reasonably, the principle of generative process was applied to simultaneous leaching of chalcopyrite concentrate and MnO2. The results show that Cu^2＋ and Mn^2＋ in addition to electrical energy could be acquired in the simultaneous electrogenerative leaching process. The leaching cell has the open circuit potential of about 1.0 V and gains quantity of electricity of about 700 C. The optimum leaching rates of Cu^2＋ and Mn^2＋ are 23.10% and 22.1%, respectively after electrogenera- tive leaching for about 10 h under the present conditions.展开更多
Abstract Objective To investigate the theoretical model of the three-dimensional structure of mosquitocida Cry3OCa2 and its molecular docking with N-acetylgalactosamine. Methods The theoretical model of Cry30Ca2 was t...Abstract Objective To investigate the theoretical model of the three-dimensional structure of mosquitocida Cry3OCa2 and its molecular docking with N-acetylgalactosamine. Methods The theoretical model of Cry30Ca2 was the Cry4Ba. Docking studies were performed N-acetylgalactosamine on the putative receptor. predicted by homology modeling on the structure of to investigate the interaction of Cry3OCa2 with Results Cry3OCa2 toxin is a rather compact molecule composed of three distinct domains and has approximate overall dimensions of 95 by 75 by 60A. Domain I is a helix bundle, Domain Ⅱ consists of three antiparallel β-sheets, Domain Ⅲ is composed of two β-sheets that adopt a 13-sandwich fold. Residue 32111e in loop1, residues 342Gin 343Thr and 345Gin in loop2, residue 393Tyr in loop3 of Cry3OCa2 are responsible for the interactions with GalNAc via 7 hydrogen bonds, 6 of them were related to the oxygen atoms of hydroxyls of the ligand, and one to the nitrogen of the ligand. Conclusion The 3D structure of Cry3OCa2 resembles the previously reported Cry toxin structures but shows still some distinctions. Several residues in the loops of the apex of domain Ⅱ are responsible for the interactions with N-acetylgalactosamine.展开更多
The polyoxometalate （CPFX-HCl）3H3PW12O40·.8H2O was prepared and characterized by elemental analysis, IR spectra and TG-DTA-DTG. The thermal decomposition mechanism and non-isothermal kinetic parameters of the p...The polyoxometalate （CPFX-HCl）3H3PW12O40·.8H2O was prepared and characterized by elemental analysis, IR spectra and TG-DTA-DTG. The thermal decomposition mechanism and non-isothermal kinetic parameters of the polyoxometalate were obtained from the analysis of TG-DTG data using the Achar equation, Coats-Redfern equation （CR）, Madhusudanan-Krishnan-Ninan equation （MKN） and Horowitz-Metzger equation （HM）. And their mathematical expressions of the kinetic compensation effect were also calculated.展开更多
A novel environmental friendly catalyst, H3PW12O40/MCM-48, was prepared by impregnation method. The catalysts were characterized by means of XRD and FT-IR. The synthesis of n-butyl methacrylate catalyzed by H3PW12O40/...A novel environmental friendly catalyst, H3PW12O40/MCM-48, was prepared by impregnation method. The catalysts were characterized by means of XRD and FT-IR. The synthesis of n-butyl methacrylate catalyzed by H3PW12O40/MCM-48 was studied with methacrylic acid and n-butyl alcohol as reactants. H3PW12O40/MCM-48 is an excellent catalyst for synthesizing n-butyl methacrylate and Keggin structure of H3PW12O40 kept unchanged after being impregnated on surface of the molecular sieve support. Effects of n（methacrylic acid）：n（n-butyl alcohol）, catalyst dosage, cyclohexane（water-stripped reagent） and reaction time on yields of the product were investigated. The optimum conditions have been found, that is, molar ratio of acid to alcohol is 1：1.6, mass ratio of catalyst used to the reactants is 0.5% and reaction time is 2.0 h. Under these conditions, the yield of n-butyl methacrylate can reach 93.7%.展开更多
A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m （TiO2）： m （H3PW6Mo6O40） is 1：2.0, volume of water is 30 mL, the reflux react...A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m （TiO2）： m （H3PW6Mo6O40） is 1：2.0, volume of water is 30 mL, the reflux reaction time is 2 h, and activated temperature is 150 ℃. H3PW6Mo6O40/TiO2 was used as catalyst in catalytic synthesis ofacetals and ketals. Effects ofn （aldehyde（ketone））： n （glycol）, catalyst dosage and reaction time on yield were investigated. Optimal conditions were： n（aldehyde （ketone））： n （glycol）=1.0 ： 1.4; mass fraction of catalyst to reactants, 0.8%; reaction time, 1.0 h and cyclohexane as water-stripped reagent, 10 mL. Under these conditions, yields of acetals and ketals can reach 53.0% -86.9 0%展开更多
[Objectives]The effects of metal elements in irrigation water in the tobacco areas of southern Anhui on the coke sweet aroma of tobacco leaves was determined.[Methods]53 representative areas for tobacco planting in so...[Objectives]The effects of metal elements in irrigation water in the tobacco areas of southern Anhui on the coke sweet aroma of tobacco leaves was determined.[Methods]53 representative areas for tobacco planting in southern Anhui were selected,and the quality of irrigation water,especially the content of metal elements,was investigated.[Results]The contents of micro(medium)elements in the irrigation water were too low to have a significant effect on the formation of the coke sweet aroma style of tobacco leaves.The contents of Mg,Ca and Zn were 0.7-8.0,<40 and 0.002-0.029 mg/L,respectively.The heavy metal contents of the irrigation water and other basic control items all met corresponding national standards.Furthermore,the tobacco planting experiment under controlled irrigation using paddy soil in the greenhouse proved that Zn was a negative correlation factor for forming the coke sweet aroma style of tobacco and the threshold value was≥10 mg/L in the irrigation water.Meanwhile,Mg was a positive correlation factor and the content of Mg to promote the coke sweet aroma style should be maintained at 40-90 mg/L.Ca and Mg had a synergistic effect,which was mainly appropriate for acid paddy soils.[Conclusions]This study improves the quality and yield of the coke sweet aroma of tobacco leaves,and has important theoretical and practical value for the formation of a popular agronomic control method.展开更多
The complex of Eu（IH） with 1-（6-hydroxy- 1-naphthyl）- 1,3-butanedione （HNBD） was prepared for the first time and characterized by elemental analysis, IR, UV, fluorescence spectrum, and DTA-TG-DTG techniques. The...The complex of Eu（IH） with 1-（6-hydroxy- 1-naphthyl）- 1,3-butanedione （HNBD） was prepared for the first time and characterized by elemental analysis, IR, UV, fluorescence spectrum, and DTA-TG-DTG techniques. The IR and UV-visible spectra showed that Eu（Ⅲ） ion was coordinated to the HNBD ligand. The fluorescence spectrum showed the presence of Eu^3＋ characteristic emission. The TG-DTA-DTG curves showed that the thermal decomposition of the anhydrous complex was a two-stage process and the final residue was Eu2O3. The thermal decomposition kinetic parameters of the complex were evaluated from TG-DTG data by using three kinds of integral methods （Coat-Redfem equation, Horowitz and Metzger equation, Madhusudanan-Krishnan-Ninan equation）. The kinetic parameters of the first stage are E^＊ = 164.02 kJ.moll, A = 1.31 × 10^15 s^-l, AS^＊= 42.27 J·K^-l·mol^-l, △H^＊ = 159.51 kJ·mol^-l, △G^＊= 136.54 kJ·mol^-l, and n = 3.1, those of the second stage are E^＊= 128.52 kJ·mol^-l, A = 1.44× 106 s^-1, △S^＊= - 136.89 J·K^-l·mol^-l, △H^＊ = 120.41 kJ·mol^-l, △G^＊= 283.85 kJ·mol^-l, and n = 1.1.展开更多
Some new heteropolyoxometalates of large organic cations with molybdotungstosilicic acids （general formula： （CTMA）4SiMoxW12-xO40·mH2O·nDMF, x=0,2,4,6,8,10,12） were prepared by the reaction of cetyltrime...Some new heteropolyoxometalates of large organic cations with molybdotungstosilicic acids （general formula： （CTMA）4SiMoxW12-xO40·mH2O·nDMF, x=0,2,4,6,8,10,12） were prepared by the reaction of cetyltrimethylammonium bromide （CTMAB,C16H33N（CH3）3Br） with H4SiMoxW12-xO40（x=0,2,4,6,8,10,12） in aqueous solution and recrystallization in DMF, and characterized by elemental analysis, IR spectra,TG- DTA and XRD techniques. The IR spectrum confirms the presence of Keggin structure and organic cations in these compounds, and it is indicated that the stretching vibration of the M-Od, M-Ob-M and Si-Oa becomes more red-shifted when molybdenum is gradually substituted for the tungsten atom. In particular, the thermal decomposition of the heteropolyoxometalates was studied in nitrogen atmosphere. The TG-DTA curves show that their thermal behaviors not only contain the release of water molecule, DMF molecule, CTMA and its fragments but also contains simultaneous collapse of Keggin anion. Their end products of the thermal decomposition are the mixture of WO3, MoO3 and SiO2. And from the final decomposition temperature of view, it is found that the thermal stability of these compounds gradually is decreased when the number of molybdenum atoms is increased.展开更多
A novel supramolecular polymolybdic（VI） acid was unexpectedly synthesized by the reaction of sodium molybdate with 1,2,4,5-benzenetetracarboxylic and trichloroacetic acids in 1：1：1 molar ratio under hydrothermal c...A novel supramolecular polymolybdic（VI） acid was unexpectedly synthesized by the reaction of sodium molybdate with 1,2,4,5-benzenetetracarboxylic and trichloroacetic acids in 1：1：1 molar ratio under hydrothermal condition. The crystal belongs to tetragonal with space group P4/mbm, a = 0.88867（17）, b = 0.88867（17）, c = 0.55676（15） nm, Z = 3, V = 0.43969（17） nm^3, Dc = 4.486 g/cm^3,μ = 4.365 mm^-1, F（000） = 576, R = 0.0273 and wR = 0.0679. In the crystal, the Mo（VI） atoms are six- and five-coordinated in distorted octahedral and trigonal bipyramidal geometries, respectively. Furthermore, these Mo（VI） atoms, bearing different coordinated environments, are bridged by OH groups with disorder O atoms to form a twodimensional framework with pentagonal grids. It is worthy of notice that these adjacent twodimensional frameworks are extended into a three-dimensional supramolecular array with pentagonal large cavities＇by Van Der Waals＇ forces and hydrogen bonding interactions.展开更多
In this analysis, the single crystal of schiff base has been synthesized and the purity of material has been increased by repeated recrystallization process. Single crystal was grown by adopting the method growing in ...In this analysis, the single crystal of schiff base has been synthesized and the purity of material has been increased by repeated recrystallization process. Single crystal was grown by adopting the method growing in a slow evaporation solution using ethanol as solvent at room temperature. A new fluorescent molecule based on Schiff base has been synthesised and its binding properties investigated by fluorescence spectroscopy to show that it can selectively bind Cu2+ with fluorescence quenching.展开更多
[Objective]The research aimed to study preparation and application of the environment-friendly compound flocculant.[Method]Chitosan（natural biological product,CTS）,ferric sulfate[Fe2（SO4） 3]and polymeric aluminum ...[Objective]The research aimed to study preparation and application of the environment-friendly compound flocculant.[Method]Chitosan（natural biological product,CTS）,ferric sulfate[Fe2（SO4） 3]and polymeric aluminum chloride（PAC） as the main raw materials,four kinds of environment-friendly flocculants were made to conduct flocculation treatment on the domestic wastewater of Wuhan Bioengineering Institute.COD and turbidity of the wastewater as the main indicators,influences of the compound flocculant formulation,flocculant dosage and pH on flocculation effect were studied.[Result]CTS/PAC and CTS/Fe2（SO4） 3 compound flocculants had better removal rates for COD and turbidity when compared with single inorganic flocculant.The best volume ratio of CTS/PAC was 1.0：5.0.The smallest dosage of CTS/PAC in each 500 ml of water sample was 4.0 ml.When pH was 7.2,removal rates of the COD and turbidity were respectively 78.5% and 98.4%,which rose by 36.5% and 21.5% respectively than that singly using PAC.[Conclusion]CTS/PAC was a kind of ideal compound flocculant and had better application prospect.展开更多
基金Funded by the Hubei Provincial Natural Science Foundation of China(No.2024AFB946)the Excellent Young and Middle-aged Science and Technology Innovation Team Plan of Hubei Colleges(No.T201824)。
文摘Three kinds of iron nanoparticles(FeNPs)were prepared via green route based on pomegranate(PG),green tea(GT),and mulberry(ML)extracts under ambient conditions.The obtained materials were characterized by scanning electron microscopy(SEM),transmission electronic microscopy(TEM),X-ray energy-dispersive spectrometer(EDS),X-ray diffraction(XRD),fourier transform infrared spectroscopy(FTIR),and X-ray photoelectron spectroscopy(XPS)techniques.The experimental results show that FeNPs were in the form of amorphous iron(Ⅱ,Ⅲ)-polyphenol complex with different dispersity and morphologies.GT-Fe has the smallest size range of 25-35 nm,PG-Fe has a moderate size-distribution of 30-40 nm,while ML-Fe formed a tuberous net-type with a sheeting structure.PG-Fe displays the highest removal efficiency of 90.2%in 20 min towards cationic dye of malachite green(16.6%by ML-Fe and 69.3%by GT-Fe),which is attributed to its highest polyphenol content,lowest zeta potential,as well as the most Fe^(2+)on the surface of FeNPs.The removal mechanism was mainly induced by electrostatic adsorption based on pH and zeta potential tests.
基金supported by the Natural Science Foundation of Hubei Province,China(No.2005ABA053)Hubei Key Laboratory of Bioanalytical Technique,and the National Natural Science Foundation of China(No.20471044).
文摘A new environmental friendly catalyst H3PW12O40/PAn was prepared and identified by means of FT-IR,XRD,and TG/DTA.The optimum conditions have been found;that is,the mass ratio of PAn to H3PW12O40 is 1：1.5,the volume of methanol is 20 mL,and the reflux reaction time is 3 h.The structural identity of Keggin units is preserved after the incorporation into polyaniline matrix.Catalytic activities of H3PW12O40/PAn in synthesizing 2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane,2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane,cyclohexanone ethylene ketal,cyclohexanone 1,2-propanediol ketal,butanone ethylene ketal,butanone 1,2-propanediol ketal,2-phenyl-1,3-dioxolane,4-methyl-2-phenyl-1,3-dioxolane,2-propyl-1,3-dioxolane,and 4-methyl-2-propyl-1,3-dioxolane were reported.It has been demon-strated that H3PW12O40/PAn is an excellent catalyst.Various factors concerned in these reactions were investigated.The optimum conditions are as follows：the molar ratio of aldehyde/ketone to glycol（r） is 1：1.5,the mass ratio of the catalyst used to the reactants is 0.6%,and the reaction time is 1.0 h.Under these conditions,the yield is as follows：2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane,69.0%;2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane,79.5%;cyclohexanone ethylene ketal,78.9%;cyclohexanone 1,2-propanediol ketal,85.3%;butanone ethylene ketal,56.9%;butanone 1,2-propanediol ketal,78.1%;2-phenyl-1,3-dioxolane,76.3%;4-methyl-2-phenyl-1,3-dioxolane,94.2%;2-propyl-1,3-dioxolane,70.7%;and 4-methyl-2-propyl-1,3-dioxolane,79.2%.
基金Project supported by the Natural Science Foundation of HubeiProvince Education Committee (No. 2004D007) and the NationalNatural Science Foundation of China (No. 20471044)
文摘Catalytic activity of activated carbon supported tungstosilicic acidin synthesizing 2-methyl-2-ethoxycarbonylmethyl- 1,3-dioxolane, 2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane, cyclohexanone ethylene ketal, cyclohexanone 1,2-propa- nediol ketal, butanone ethylene ketal, butanone 1,2-propanediol ketal, 2-phenyl-1,3-dioxolane, 4-methyl-2-phenyl-1,3-dioxolane, 2-propyl-1,3-dioxolane, 4-methyl-2-propyl-1,3-dioxolane was reported. It has been demonstrated that activated carbon supported tungstosilicic acid is an excellent catalyst. Various factors involved in these reactions were investigated. The optimum conditions found were: molar ratio of aldehyde/ketone to glycol is 1/1.5, mass ratio of the catalyst used to the reactants is 1.0%, and reaction time is 1.0 h. Under these conditions, the yield of 2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane is 61.5%, of 2,4-dimethyl- 2-ethoxycarbonylmethyl-1,3-dioxolane is 69.1%, of cyclohexanone ethylene ketal is 74.6%, of cyclohexanone 1,2-propanediol ketal is 80.1%, of butanone ethylene ketal is 69.5%, of butanone 1,2-propanediol ketal is 78.5%, of 2-phenyl-1,3-dioxolane is 56.7%, of 4-methyl-2-phenyl-1,3-dioxolane is 86.2%, of 2-propyl-1,3-dioxolane is 87.5%, of 4-methyl-2-propyl-1,3-dioxolane is 87.9%.
文摘SO4^2-/TiO2-MoO3, a novel solid superacid, has been prepared and its catalytic activity at different synthetic conditions was examined with esterification of n-butanoic acid and n-butyl alcohol as probing reaction.The optimum conditions were also found, that is, the mass ratio of MoO3 used in the compound is 25%, the calcination temperature 450℃, and the soaked consistency of H2SO4 is 0.5mol.L^-1. Then it was applied in the catalytic synthesis of six similar important ketals and acetals as catalyst and revealed high catalytic activity. Under the condition that the molar ratio of aldehyde/ketone to glycol was 1:1.5, the mass ratio of the catalyst to the reactants was 0.5% and the reaction time 1.0 h, the yield of ketals and acetals reached up to 63.2%. The catalyst can be easily recovered and reused.
基金This work was financially supported by the Natural Science Foundation of Hubei Province, China (No. 2005ABA053) and the National Natural Science Foundation of China (No. 20471044).
文摘Twelve classes of acetals and ketals were synthesized from aldehyde/ketone and glycol using ZiSiW12O40/TiO2 as a novel eco-friendly catalyst. The physical characterizations were carried out by TG/DTA, FT-IR, XRD, and ^1H NMR spectra. The results indicated that the catalyst showed excellent catalytic activity for the condensation reactions. The yield of 12 classes of acetals and ketals reached 56.3%-96.3% under the typical reaction conditions （the molar ratio of aldehyde/ketone and glycol was 1：1.5, the quantity of catalyst was 0.5% of feed stock, the reaction time was 1.0 h, and the reaction temperature was 80-116℃）. The catalyst was easily recovered and reused to give almost the same yield of the product as that given by fresh TiSiW12O10/TiO2.
基金Project supported by the National Natural Science Foundation of China (No. 20471044), and the Natural Science Foundation of Hubei Province (No. 2005ABA053), China
文摘SO4^2- / TiO2-La2O3, a novel solid superacid, was prepared and its catalytic activities at different synthetic conditions are discussed with esterification of n-butanoic acid and n-butyl alcohol as probing reaction. The optimum conditions have also been found, mole ratio of n（La^3＋）：n（Ti^4＋） is 1：34, the soaked consistency of H2SO4 is 0.8 tool/L, the soaked time of HESO4 is 24 h, the calcining temperature is 480 ℃, the calcining time is 3 h. Then it was applied in the catalytic synthesis often important ketals and acetals as catalyst and revealed high catalytic activity. Under these conditions on which the molar ratio of aldehyde/ketone to glycol is l： 1.5, the mass ratio of the catalyst used in the reactants is 0.5%, and the reaction time is 1.0 h, the yields of ketals and acetals can reach 41.4%-95.8%.
基金This work was supported by the National Natural Science Foundation of China (No. 20571057)
文摘The title compound, [Cu（C6H4N2O4F）2（H2O）4].4（H2O） I, has been hydrothermally synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in monoclinic, space group P21/c with a = 8.3041（17）, b = 12.045（2）, c = 11.077（2） A, β = 92.567（3）°, V= 1106.8（4） A^3, Mr = 581.89, Z= 2, Dc = 1.746 g/cm^3, F（000） = 598,μ（MoKa） = 1.090 mm^-1, the final R = 0.0296 and wR = 0.0806 for 3195 observed reflections with Ⅰ 〉 2σ（Ⅰ）. In the centrosymmetric compound I, each Cu（Ⅱ） ion is coordinated by six O atoms from two 5-fluorouracil-1-acetate anions and four water molecules, forming a six-coordinated octahedral environment. N-H…O and O-H…O hydrogen-bonding interactions are observed in the structure, leading to the formation of a three-dimensional network.
文摘In order to enhance the electrogenerative leaching rate of chalcopyrite concentrate reasonably, the principle of generative process was applied to simultaneous leaching of chalcopyrite concentrate and MnO2. The results show that Cu^2＋ and Mn^2＋ in addition to electrical energy could be acquired in the simultaneous electrogenerative leaching process. The leaching cell has the open circuit potential of about 1.0 V and gains quantity of electricity of about 700 C. The optimum leaching rates of Cu^2＋ and Mn^2＋ are 23.10% and 22.1%, respectively after electrogenera- tive leaching for about 10 h under the present conditions.
基金supported by grants from Hunan Provincial Natural Science Foundation of China(No.12JJ3021)the National Natural Science Foundation of China(No.30670052,30570050)863 Program of China(2006AA02Z187)
文摘Abstract Objective To investigate the theoretical model of the three-dimensional structure of mosquitocida Cry3OCa2 and its molecular docking with N-acetylgalactosamine. Methods The theoretical model of Cry30Ca2 was the Cry4Ba. Docking studies were performed N-acetylgalactosamine on the putative receptor. predicted by homology modeling on the structure of to investigate the interaction of Cry3OCa2 with Results Cry3OCa2 toxin is a rather compact molecule composed of three distinct domains and has approximate overall dimensions of 95 by 75 by 60A. Domain I is a helix bundle, Domain Ⅱ consists of three antiparallel β-sheets, Domain Ⅲ is composed of two β-sheets that adopt a 13-sandwich fold. Residue 32111e in loop1, residues 342Gin 343Thr and 345Gin in loop2, residue 393Tyr in loop3 of Cry3OCa2 are responsible for the interactions with GalNAc via 7 hydrogen bonds, 6 of them were related to the oxygen atoms of hydroxyls of the ligand, and one to the nitrogen of the ligand. Conclusion The 3D structure of Cry3OCa2 resembles the previously reported Cry toxin structures but shows still some distinctions. Several residues in the loops of the apex of domain Ⅱ are responsible for the interactions with N-acetylgalactosamine.
基金the Natural Science Foundation of the Educational Commission of Hubei Province(No.J200522002 and Z200622001)
文摘The polyoxometalate （CPFX-HCl）3H3PW12O40·.8H2O was prepared and characterized by elemental analysis, IR spectra and TG-DTA-DTG. The thermal decomposition mechanism and non-isothermal kinetic parameters of the polyoxometalate were obtained from the analysis of TG-DTG data using the Achar equation, Coats-Redfern equation （CR）, Madhusudanan-Krishnan-Ninan equation （MKN） and Horowitz-Metzger equation （HM）. And their mathematical expressions of the kinetic compensation effect were also calculated.
基金Funded by the Natural Science Foundation of Hubei Province,China(No.2005ABA053)the National Natural ScienceFoundation of China(No.20471044)
文摘A novel environmental friendly catalyst, H3PW12O40/MCM-48, was prepared by impregnation method. The catalysts were characterized by means of XRD and FT-IR. The synthesis of n-butyl methacrylate catalyzed by H3PW12O40/MCM-48 was studied with methacrylic acid and n-butyl alcohol as reactants. H3PW12O40/MCM-48 is an excellent catalyst for synthesizing n-butyl methacrylate and Keggin structure of H3PW12O40 kept unchanged after being impregnated on surface of the molecular sieve support. Effects of n（methacrylic acid）：n（n-butyl alcohol）, catalyst dosage, cyclohexane（water-stripped reagent） and reaction time on yields of the product were investigated. The optimum conditions have been found, that is, molar ratio of acid to alcohol is 1：1.6, mass ratio of catalyst used to the reactants is 0.5% and reaction time is 2.0 h. Under these conditions, the yield of n-butyl methacrylate can reach 93.7%.
基金Acknowledgements： This work was financially supported by the Natural Science Foundation of Hubei Province, China （No. 2005ABA053） and the National Natural Science Foundation of China （No. 20471044）.
文摘A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m （TiO2）： m （H3PW6Mo6O40） is 1：2.0, volume of water is 30 mL, the reflux reaction time is 2 h, and activated temperature is 150 ℃. H3PW6Mo6O40/TiO2 was used as catalyst in catalytic synthesis ofacetals and ketals. Effects ofn （aldehyde（ketone））： n （glycol）, catalyst dosage and reaction time on yield were investigated. Optimal conditions were： n（aldehyde （ketone））： n （glycol）=1.0 ： 1.4; mass fraction of catalyst to reactants, 0.8%; reaction time, 1.0 h and cyclohexane as water-stripped reagent, 10 mL. Under these conditions, yields of acetals and ketals can reach 53.0% -86.9 0%
文摘[Objectives]The effects of metal elements in irrigation water in the tobacco areas of southern Anhui on the coke sweet aroma of tobacco leaves was determined.[Methods]53 representative areas for tobacco planting in southern Anhui were selected,and the quality of irrigation water,especially the content of metal elements,was investigated.[Results]The contents of micro(medium)elements in the irrigation water were too low to have a significant effect on the formation of the coke sweet aroma style of tobacco leaves.The contents of Mg,Ca and Zn were 0.7-8.0,<40 and 0.002-0.029 mg/L,respectively.The heavy metal contents of the irrigation water and other basic control items all met corresponding national standards.Furthermore,the tobacco planting experiment under controlled irrigation using paddy soil in the greenhouse proved that Zn was a negative correlation factor for forming the coke sweet aroma style of tobacco and the threshold value was≥10 mg/L in the irrigation water.Meanwhile,Mg was a positive correlation factor and the content of Mg to promote the coke sweet aroma style should be maintained at 40-90 mg/L.Ca and Mg had a synergistic effect,which was mainly appropriate for acid paddy soils.[Conclusions]This study improves the quality and yield of the coke sweet aroma of tobacco leaves,and has important theoretical and practical value for the formation of a popular agronomic control method.
基金financially supported by the Important Foundation of the Educational Commission of Hubei Province (No. Z200622001)the Natural Science Foundation of the Educational Commission of Hubei Province, China (No. J200522002)
文摘The complex of Eu（IH） with 1-（6-hydroxy- 1-naphthyl）- 1,3-butanedione （HNBD） was prepared for the first time and characterized by elemental analysis, IR, UV, fluorescence spectrum, and DTA-TG-DTG techniques. The IR and UV-visible spectra showed that Eu（Ⅲ） ion was coordinated to the HNBD ligand. The fluorescence spectrum showed the presence of Eu^3＋ characteristic emission. The TG-DTA-DTG curves showed that the thermal decomposition of the anhydrous complex was a two-stage process and the final residue was Eu2O3. The thermal decomposition kinetic parameters of the complex were evaluated from TG-DTG data by using three kinds of integral methods （Coat-Redfem equation, Horowitz and Metzger equation, Madhusudanan-Krishnan-Ninan equation）. The kinetic parameters of the first stage are E^＊ = 164.02 kJ.moll, A = 1.31 × 10^15 s^-l, AS^＊= 42.27 J·K^-l·mol^-l, △H^＊ = 159.51 kJ·mol^-l, △G^＊= 136.54 kJ·mol^-l, and n = 3.1, those of the second stage are E^＊= 128.52 kJ·mol^-l, A = 1.44× 106 s^-1, △S^＊= - 136.89 J·K^-l·mol^-l, △H^＊ = 120.41 kJ·mol^-l, △G^＊= 283.85 kJ·mol^-l, and n = 1.1.
基金the Natural Science Foundation of the Educational Commission of Hubei Province(No.J200522002 and Z200622001)
文摘Some new heteropolyoxometalates of large organic cations with molybdotungstosilicic acids （general formula： （CTMA）4SiMoxW12-xO40·mH2O·nDMF, x=0,2,4,6,8,10,12） were prepared by the reaction of cetyltrimethylammonium bromide （CTMAB,C16H33N（CH3）3Br） with H4SiMoxW12-xO40（x=0,2,4,6,8,10,12） in aqueous solution and recrystallization in DMF, and characterized by elemental analysis, IR spectra,TG- DTA and XRD techniques. The IR spectrum confirms the presence of Keggin structure and organic cations in these compounds, and it is indicated that the stretching vibration of the M-Od, M-Ob-M and Si-Oa becomes more red-shifted when molybdenum is gradually substituted for the tungsten atom. In particular, the thermal decomposition of the heteropolyoxometalates was studied in nitrogen atmosphere. The TG-DTA curves show that their thermal behaviors not only contain the release of water molecule, DMF molecule, CTMA and its fragments but also contains simultaneous collapse of Keggin anion. Their end products of the thermal decomposition are the mixture of WO3, MoO3 and SiO2. And from the final decomposition temperature of view, it is found that the thermal stability of these compounds gradually is decreased when the number of molybdenum atoms is increased.
基金This work was supported by the National Natural Science Foundation of China (No. 20571057)
文摘A novel supramolecular polymolybdic（VI） acid was unexpectedly synthesized by the reaction of sodium molybdate with 1,2,4,5-benzenetetracarboxylic and trichloroacetic acids in 1：1：1 molar ratio under hydrothermal condition. The crystal belongs to tetragonal with space group P4/mbm, a = 0.88867（17）, b = 0.88867（17）, c = 0.55676（15） nm, Z = 3, V = 0.43969（17） nm^3, Dc = 4.486 g/cm^3,μ = 4.365 mm^-1, F（000） = 576, R = 0.0273 and wR = 0.0679. In the crystal, the Mo（VI） atoms are six- and five-coordinated in distorted octahedral and trigonal bipyramidal geometries, respectively. Furthermore, these Mo（VI） atoms, bearing different coordinated environments, are bridged by OH groups with disorder O atoms to form a twodimensional framework with pentagonal grids. It is worthy of notice that these adjacent twodimensional frameworks are extended into a three-dimensional supramolecular array with pentagonal large cavities＇by Van Der Waals＇ forces and hydrogen bonding interactions.
文摘In this analysis, the single crystal of schiff base has been synthesized and the purity of material has been increased by repeated recrystallization process. Single crystal was grown by adopting the method growing in a slow evaporation solution using ethanol as solvent at room temperature. A new fluorescent molecule based on Schiff base has been synthesised and its binding properties investigated by fluorescence spectroscopy to show that it can selectively bind Cu2+ with fluorescence quenching.
基金Supported by Science Plan Item of Hubei Education Department(B20084001)
文摘[Objective]The research aimed to study preparation and application of the environment-friendly compound flocculant.[Method]Chitosan（natural biological product,CTS）,ferric sulfate[Fe2（SO4） 3]and polymeric aluminum chloride（PAC） as the main raw materials,four kinds of environment-friendly flocculants were made to conduct flocculation treatment on the domestic wastewater of Wuhan Bioengineering Institute.COD and turbidity of the wastewater as the main indicators,influences of the compound flocculant formulation,flocculant dosage and pH on flocculation effect were studied.[Result]CTS/PAC and CTS/Fe2（SO4） 3 compound flocculants had better removal rates for COD and turbidity when compared with single inorganic flocculant.The best volume ratio of CTS/PAC was 1.0：5.0.The smallest dosage of CTS/PAC in each 500 ml of water sample was 4.0 ml.When pH was 7.2,removal rates of the COD and turbidity were respectively 78.5% and 98.4%,which rose by 36.5% and 21.5% respectively than that singly using PAC.[Conclusion]CTS/PAC was a kind of ideal compound flocculant and had better application prospect.
