In order to reduce the emission of SO_x in the environment,sulfur compounds must be removed efficiently from fuels.Three-dimensional highly ordered meso-macroporous HPW/TiO_(2)(3DO m/M HPW/TiO_(2))materials were synth...In order to reduce the emission of SO_x in the environment,sulfur compounds must be removed efficiently from fuels.Three-dimensional highly ordered meso-macroporous HPW/TiO_(2)(3DO m/M HPW/TiO_(2))materials were synthesized successfully by sol-gel method and applied as oxidative desulfurization catalyst for the model fuel.The characterization results displayed the existence of highly ordered meso-macroporous structures and the Keggin type of HPW was highly dispersed in TiO_(2)framework.The effect of catalyst on desulfurization under different reaction conditions was studied systematically.The results showed that the catalyst exhibited excellent desulfurization performance in the hydrogen peroxide oxidation system,which could be explained by the unique meso-macroporous structure of catalyst.In addition,the catalyst showed good cycling performance and the removal rate of DBT still reached 96.1%even after 6 cycles,providing a feasible method for the development and application of fuel deep desulfurization catalysts.展开更多
A serial of ordered meso-macroporous phosphotungstic acid(HPW) supported on SiO2 nanocomposites were successfully prepared by a homogeneous precipitation method, using monodispersed polystyrene(PS) microspheres and ca...A serial of ordered meso-macroporous phosphotungstic acid(HPW) supported on SiO2 nanocomposites were successfully prepared by a homogeneous precipitation method, using monodispersed polystyrene(PS) microspheres and cationic surfactant as structure directing agent. These nanocomposites were used as catalysts for oxidative desulfurization(ODS) of model fuel. The materials were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), N2 adsorption-desorption isothrem, X-ray diffraction(XRD), and Fourier transform infrared spectra(FTIR). The characterization results suggested that the as-prepared material possessed ordered meso-macroporous architectures with Keggin type phosphotungstic acid dispersed homogeneously in SiO2 matrix. Under the selected reaction conditions, dibenzothiophene(DBT) in model fuel can be removed within 2 h at room temperature(30 ℃). In addition, only 1.2% of efficiency lose than the fresh catalyst even after 5 cycles.展开更多
Bridge polycarboxylate superplasticizers（PCs） with crosslink structure were synthesized by using polyethyleneglycol di-acrylate（PEGdA）, replacing partial polyethyleneglycol mono-acrylate （PEGmA） as crosslinking ...Bridge polycarboxylate superplasticizers（PCs） with crosslink structure were synthesized by using polyethyleneglycol di-acrylate（PEGdA）, replacing partial polyethyleneglycol mono-acrylate （PEGmA） as crosslinking agent. Structures of bridge PCs were analyzed by gel permeation chromatography, and dispersion ability was evaluated by cement paste dispersity variation on time and rheology test. The experimental results showed that, molecular weight（MW） of bridge PCs increased with increase of PEGdA proportion, and MW distribution curve changed from Gaussian to fiat like, which meant notable increase of highly crosslinked copolymer. Bridge PCs led to decreased initial cement paste dispersity and better dispersity retention due to slow releasing. Further research showed that, PEGdA proportion had slight effect on polymerization degree of backbone, MW distribution of backbone deviated from Gaussian distribution and shoulder peaks appeared on distribution curve when PEGdA increased.展开更多
Isotopic ages of synsedimentary clay minerals were directly determined with the ultrasonicscattering-settlement separation-K-Ar dilution technique. The apparent age of black mudstoneis 123 Ma for the Quantou Formation...Isotopic ages of synsedimentary clay minerals were directly determined with the ultrasonicscattering-settlement separation-K-Ar dilution technique. The apparent age of black mudstoneis 123 Ma for the Quantou Formation, 111.9-89.0 Ma for the Qingshankou Formation and77.6-76.8 Ma for the upper part of the Nenjiang Formation. The Rb-Sr isochrone age of themuddy limestone-mudstone sequence of the lower part of the Nenjiang Formation is 81 Ma andthat of the muddy evaporite of the middle part of the Quantou Formation is 122.2 Ma. On thebasis of the above isotopic ages, the authors propose a modified scheme of stratigraphic classifi-cation of the Cretaceous of the Songliao basin.展开更多
A series of polycarboxylate-based superplasticizers(PCs) with different structures were synthesized and the effects of chemical structure on zeta potential and rheological property of cement paste were studied. Residu...A series of polycarboxylate-based superplasticizers(PCs) with different structures were synthesized and the effects of chemical structure on zeta potential and rheological property of cement paste were studied. Residual monomers in each sample of PCs were quantitatively determined. The property of the polymers in cement was tested by micro-electrophoresis apparatus and R/S rheometer. Results showed that the zeta potential and its rheological properties are related with the side-chain length and density of PCs. The PCs having shorter side chain and lower side chain density exhibit higher anionic charge density, thus resulting in higher zeta potential. The effect of side chain density on zeta potential is more notable compared with that of side-chain length, and thus affecting the initial shear yield stress and apparent viscosity of the cement paste. In addition, although increasing the side chain length will result in reduction of the anionic charge density, the steric hindrance effect is obvious, which can effectively improve the dispersion of the cement particles, and reduce the viscosity and shear yield stress of slurry.展开更多
Three-dimensionally ordered（3DOM） macroporous phosphotungstic acid/SiO_2（HPW/SiO_2） materials were prepared by using colloidal crystal as templates and applied for oxidative desulfurization（ODS） of the model fue...Three-dimensionally ordered（3DOM） macroporous phosphotungstic acid/SiO_2（HPW/SiO_2） materials were prepared by using colloidal crystal as templates and applied for oxidative desulfurization（ODS） of the model fuel oil. The obtained HPW/SiO_2 materials were characterized through scanning electron microscopy, powder X-ray diffraction, N_2 sorption, and Fourier transform infrared spectroscopy. The results indicated that 3 DOM HPW/SiO_2 possessed hierarchical pore architectures which contained ordered macropores and disordered mesopores, with the Keggin type HPW embedded in the framework of pore structure. The removal rate of dibenzothiophene（DBT） could reach 100% under the optimum conditions, moreover. The performance was only slightly decreased for the regenerated catalyst after 7 cycles.展开更多
A series of heteropoly acid (HPA) based Al2O3 catalysts with three-dimensional ordered (3DOM) structure were synthesized by colloidal crystal template method.Interconnected macropores (250 nm) could be clearly observe...A series of heteropoly acid (HPA) based Al2O3 catalysts with three-dimensional ordered (3DOM) structure were synthesized by colloidal crystal template method.Interconnected macropores (250 nm) could be clearly observed by scanning electron microscope (SEM) and transmission electron microscope (TEM).Mesopores could be detected by N2 adsorption-desorption isotherms which further confirmed the 3DOM structural characteristics of catalyst.Moreover,Keggin-type HPW was highly dispersed in the Al2O3 framework,which suggested by powder X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR) results.The oxidation desulfurization (ODS) performance of 3DOM H3PW12O40/Al2O3 of refractory sulphur compounds was evaluated in the presence of hydrogen peroxide.It oxidized 98.5% of dibenzothiophene (DBT) into corresponding sulfone within 3 h,which exhibited superior ODS performance than corresponding mesoporous and microporous H3PW12O40/Al2O3 catalyst.The enhancement of ODS efficiency is related to the improvement of mass transfer of DBT in the pore channel resulting from the interconnected 3DOM structure.Furthermore,the as-prepared catalyst still demonstrates outstanding cycle performance after 6 runs,which could be easily recovered from the model fuel.展开更多
The synthesis and crystal smacture of an polyoxometalate-based organic-inorganic complex [Cu（DMF）3（H2O）212[SiMo12O40].2H2O （DMF = N, N-dimethyl formamide） is described in this article. It was characterized using...The synthesis and crystal smacture of an polyoxometalate-based organic-inorganic complex [Cu（DMF）3（H2O）212[SiMo12O40].2H2O （DMF = N, N-dimethyl formamide） is described in this article. It was characterized using elemental analysis, thermal analysis, infrared, ultraviolet, and electron spin resonance spectroscopic studies. The X-ray crystallography analysis showed that the copper centers are pentacoordinated to show the square pyramidal geometry, and the polyanion [SiMo12O40]4- which is semi-coordinated to the copper（I/） centers prevents the existence of a sixth ligand. In addition, the intracationic hydrogen interaction enhanced the stability of the copper coordination cation.展开更多
The synthesis, properties and dispersion mechanism of sulphonated acetone-formaldehyde superplasticizer （SAF） were presented. This superplasticizer was synthesized by the reaction among acetone, formaldehyde, sodium...The synthesis, properties and dispersion mechanism of sulphonated acetone-formaldehyde superplasticizer （SAF） were presented. This superplasticizer was synthesized by the reaction among acetone, formaldehyde, sodium sulfite and pyrosulfite. The structure and property were respectively characterized by IR and surface tension measurement. Performance of SAF in cement was evaluated by paste flow as well as heat calorimetry. The dispersion mechanism was identified via adsorption and zeta potential measurement. The results show that cement paste mixed with SAF shows good fluidity. SAF exerts little retarding effect on cement paste and it behaves like a typical polycondensate superplasticizer. The main dispersion mechanism of SAF is attributed to electrostatic repulsion.展开更多
以Na_2WO_4·2H_2O,H_3BO_3及Eu(NO_3)_3·6H_2O等为原料,利用常规溶液合成法制备了一种基于硼钨酸盐的稀土多金属氧酸盐K_(7.5)H_(4.5)[Eu(BW_(11)O_(39))(W_5O_(18))]·21.5H_2O(1)。借助于X射线单晶衍射仪(SXRD)、X射线...以Na_2WO_4·2H_2O,H_3BO_3及Eu(NO_3)_3·6H_2O等为原料,利用常规溶液合成法制备了一种基于硼钨酸盐的稀土多金属氧酸盐K_(7.5)H_(4.5)[Eu(BW_(11)O_(39))(W_5O_(18))]·21.5H_2O(1)。借助于X射线单晶衍射仪(SXRD)、X射线粉末衍射仪(PXRD)、红外光谱仪(IR)、热分析仪(TG-DTA)、以及荧光光谱仪(PL)等对样品的结构、热稳定性及发光性能进行了表征。结果表明,该化合物结晶于三斜晶系,Pī空间群,a=1.2648(3)nm,b=1.7290(4)nm,c=1.7637(4)nm,α=110.584(4)°,β=94.111(4)°,γ=96.546(4)°,V=3.5610(15)nm^3,H_(47.5)O_(78.5)BK_(7.5)EuW_(16),Mr=4701.2823,D_c=4.340 mg·m^(-3),μ(MoKα)=27.151 mm^(-1),F(000)=4045,GOF=1.019,Z=2,the final R_1=0.0389和wR_2=0.0960 for I>2θ(I)。该稀土多金属氧酸盐是以多金属氧酸盐阴离子[Eu(BW_(11)O_(39))(W_5O_(18))]^(12-)为构筑块的三维无机框架结构,该阴离子呈现夹心型构型,Eu^(3+)离子位于两个缺位阴离子[BW_(11)O_(39)]^(9-)和[W_5O_(18)]^(6-)的中间,该化合物呈现较高的热稳定性,在紫外光(λ_(ex)=394 nm)激发下,发射出较强的红光。展开更多
基金Funded by the National Nature Science Foundation of China(No.21476177)。
文摘In order to reduce the emission of SO_x in the environment,sulfur compounds must be removed efficiently from fuels.Three-dimensional highly ordered meso-macroporous HPW/TiO_(2)(3DO m/M HPW/TiO_(2))materials were synthesized successfully by sol-gel method and applied as oxidative desulfurization catalyst for the model fuel.The characterization results displayed the existence of highly ordered meso-macroporous structures and the Keggin type of HPW was highly dispersed in TiO_(2)framework.The effect of catalyst on desulfurization under different reaction conditions was studied systematically.The results showed that the catalyst exhibited excellent desulfurization performance in the hydrogen peroxide oxidation system,which could be explained by the unique meso-macroporous structure of catalyst.In addition,the catalyst showed good cycling performance and the removal rate of DBT still reached 96.1%even after 6 cycles,providing a feasible method for the development and application of fuel deep desulfurization catalysts.
基金Supported by the National Nature Science Foundation of China(No.21476177)
文摘A serial of ordered meso-macroporous phosphotungstic acid(HPW) supported on SiO2 nanocomposites were successfully prepared by a homogeneous precipitation method, using monodispersed polystyrene(PS) microspheres and cationic surfactant as structure directing agent. These nanocomposites were used as catalysts for oxidative desulfurization(ODS) of model fuel. The materials were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), N2 adsorption-desorption isothrem, X-ray diffraction(XRD), and Fourier transform infrared spectra(FTIR). The characterization results suggested that the as-prepared material possessed ordered meso-macroporous architectures with Keggin type phosphotungstic acid dispersed homogeneously in SiO2 matrix. Under the selected reaction conditions, dibenzothiophene(DBT) in model fuel can be removed within 2 h at room temperature(30 ℃). In addition, only 1.2% of efficiency lose than the fresh catalyst even after 5 cycles.
基金Funded by the Western Region Traffic Construction Technology Program of the Ministry of Transport of China(No.2007319811130)
文摘Bridge polycarboxylate superplasticizers（PCs） with crosslink structure were synthesized by using polyethyleneglycol di-acrylate（PEGdA）, replacing partial polyethyleneglycol mono-acrylate （PEGmA） as crosslinking agent. Structures of bridge PCs were analyzed by gel permeation chromatography, and dispersion ability was evaluated by cement paste dispersity variation on time and rheology test. The experimental results showed that, molecular weight（MW） of bridge PCs increased with increase of PEGdA proportion, and MW distribution curve changed from Gaussian to fiat like, which meant notable increase of highly crosslinked copolymer. Bridge PCs led to decreased initial cement paste dispersity and better dispersity retention due to slow releasing. Further research showed that, PEGdA proportion had slight effect on polymerization degree of backbone, MW distribution of backbone deviated from Gaussian distribution and shoulder peaks appeared on distribution curve when PEGdA increased.
基金Note:The study was supported by the China National Natural Science Foundation Grant No 49172107.
文摘Isotopic ages of synsedimentary clay minerals were directly determined with the ultrasonicscattering-settlement separation-K-Ar dilution technique. The apparent age of black mudstoneis 123 Ma for the Quantou Formation, 111.9-89.0 Ma for the Qingshankou Formation and77.6-76.8 Ma for the upper part of the Nenjiang Formation. The Rb-Sr isochrone age of themuddy limestone-mudstone sequence of the lower part of the Nenjiang Formation is 81 Ma andthat of the muddy evaporite of the middle part of the Quantou Formation is 122.2 Ma. On thebasis of the above isotopic ages, the authors propose a modified scheme of stratigraphic classifi-cation of the Cretaceous of the Songliao basin.
基金Funded by the Western Region Traffic Construction Technology Program of the Ministry of Communications of China(No.2007319811130)
文摘A series of polycarboxylate-based superplasticizers(PCs) with different structures were synthesized and the effects of chemical structure on zeta potential and rheological property of cement paste were studied. Residual monomers in each sample of PCs were quantitatively determined. The property of the polymers in cement was tested by micro-electrophoresis apparatus and R/S rheometer. Results showed that the zeta potential and its rheological properties are related with the side-chain length and density of PCs. The PCs having shorter side chain and lower side chain density exhibit higher anionic charge density, thus resulting in higher zeta potential. The effect of side chain density on zeta potential is more notable compared with that of side-chain length, and thus affecting the initial shear yield stress and apparent viscosity of the cement paste. In addition, although increasing the side chain length will result in reduction of the anionic charge density, the steric hindrance effect is obvious, which can effectively improve the dispersion of the cement particles, and reduce the viscosity and shear yield stress of slurry.
基金the National Nature Science Foundation of China(No.21476177)
文摘Three-dimensionally ordered（3DOM） macroporous phosphotungstic acid/SiO_2（HPW/SiO_2） materials were prepared by using colloidal crystal as templates and applied for oxidative desulfurization（ODS） of the model fuel oil. The obtained HPW/SiO_2 materials were characterized through scanning electron microscopy, powder X-ray diffraction, N_2 sorption, and Fourier transform infrared spectroscopy. The results indicated that 3 DOM HPW/SiO_2 possessed hierarchical pore architectures which contained ordered macropores and disordered mesopores, with the Keggin type HPW embedded in the framework of pore structure. The removal rate of dibenzothiophene（DBT） could reach 100% under the optimum conditions, moreover. The performance was only slightly decreased for the regenerated catalyst after 7 cycles.
基金Funded by the National Natural Science Foundation of China(No.21476177)。
文摘A series of heteropoly acid (HPA) based Al2O3 catalysts with three-dimensional ordered (3DOM) structure were synthesized by colloidal crystal template method.Interconnected macropores (250 nm) could be clearly observed by scanning electron microscope (SEM) and transmission electron microscope (TEM).Mesopores could be detected by N2 adsorption-desorption isotherms which further confirmed the 3DOM structural characteristics of catalyst.Moreover,Keggin-type HPW was highly dispersed in the Al2O3 framework,which suggested by powder X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR) results.The oxidation desulfurization (ODS) performance of 3DOM H3PW12O40/Al2O3 of refractory sulphur compounds was evaluated in the presence of hydrogen peroxide.It oxidized 98.5% of dibenzothiophene (DBT) into corresponding sulfone within 3 h,which exhibited superior ODS performance than corresponding mesoporous and microporous H3PW12O40/Al2O3 catalyst.The enhancement of ODS efficiency is related to the improvement of mass transfer of DBT in the pore channel resulting from the interconnected 3DOM structure.Furthermore,the as-prepared catalyst still demonstrates outstanding cycle performance after 6 runs,which could be easily recovered from the model fuel.
基金financially supported by the National Natural Science Foundation of China (No. 2057023)the Program for New Century Excellent Talents in Universities of Henan Province (No. 2005HANCET)+2 种基金the Specialized Research Fund for the Doctoral Program of Higher Education (No. 20040475001)Henan Innovation Project for University Prominent Re-search Talents (No. 2005KYCX011)the Natural Science Foundation of Henan Province, China (No. 0411051700)
文摘The synthesis and crystal smacture of an polyoxometalate-based organic-inorganic complex [Cu（DMF）3（H2O）212[SiMo12O40].2H2O （DMF = N, N-dimethyl formamide） is described in this article. It was characterized using elemental analysis, thermal analysis, infrared, ultraviolet, and electron spin resonance spectroscopic studies. The X-ray crystallography analysis showed that the copper centers are pentacoordinated to show the square pyramidal geometry, and the polyanion [SiMo12O40]4- which is semi-coordinated to the copper（I/） centers prevents the existence of a sixth ligand. In addition, the intracationic hydrogen interaction enhanced the stability of the copper coordination cation.
基金Funded by the Western Region Traffic Construction Technology Program of the Ministry of Communications of China(No.2007319811130)
文摘The synthesis, properties and dispersion mechanism of sulphonated acetone-formaldehyde superplasticizer （SAF） were presented. This superplasticizer was synthesized by the reaction among acetone, formaldehyde, sodium sulfite and pyrosulfite. The structure and property were respectively characterized by IR and surface tension measurement. Performance of SAF in cement was evaluated by paste flow as well as heat calorimetry. The dispersion mechanism was identified via adsorption and zeta potential measurement. The results show that cement paste mixed with SAF shows good fluidity. SAF exerts little retarding effect on cement paste and it behaves like a typical polycondensate superplasticizer. The main dispersion mechanism of SAF is attributed to electrostatic repulsion.
文摘以Na_2WO_4·2H_2O,H_3BO_3及Eu(NO_3)_3·6H_2O等为原料,利用常规溶液合成法制备了一种基于硼钨酸盐的稀土多金属氧酸盐K_(7.5)H_(4.5)[Eu(BW_(11)O_(39))(W_5O_(18))]·21.5H_2O(1)。借助于X射线单晶衍射仪(SXRD)、X射线粉末衍射仪(PXRD)、红外光谱仪(IR)、热分析仪(TG-DTA)、以及荧光光谱仪(PL)等对样品的结构、热稳定性及发光性能进行了表征。结果表明,该化合物结晶于三斜晶系,Pī空间群,a=1.2648(3)nm,b=1.7290(4)nm,c=1.7637(4)nm,α=110.584(4)°,β=94.111(4)°,γ=96.546(4)°,V=3.5610(15)nm^3,H_(47.5)O_(78.5)BK_(7.5)EuW_(16),Mr=4701.2823,D_c=4.340 mg·m^(-3),μ(MoKα)=27.151 mm^(-1),F(000)=4045,GOF=1.019,Z=2,the final R_1=0.0389和wR_2=0.0960 for I>2θ(I)。该稀土多金属氧酸盐是以多金属氧酸盐阴离子[Eu(BW_(11)O_(39))(W_5O_(18))]^(12-)为构筑块的三维无机框架结构,该阴离子呈现夹心型构型,Eu^(3+)离子位于两个缺位阴离子[BW_(11)O_(39)]^(9-)和[W_5O_(18)]^(6-)的中间,该化合物呈现较高的热稳定性,在紫外光(λ_(ex)=394 nm)激发下,发射出较强的红光。
