Zero liquid discharge(ZLD)treatment and reuse equipment of high salinity wastewater in coal-chemical industry often occur in various types of blockage problems because of high salt content,affecting the long-term stab...Zero liquid discharge(ZLD)treatment and reuse equipment of high salinity wastewater in coal-chemical industry often occur in various types of blockage problems because of high salt content,affecting the long-term stability of the device.In this study,the effects of solution temperature,steel,reaction time and wall roughness on fouling were investigated.The changes in the contents of fouling and fouling substances were qualitatively and quantitatively analyzed by XRD and EDS respectively,and the formation of scale was observed by SEM.The results show that with temperature increasing,Q235 steel is the most difficult to scale.Scaling rate of all salt scales reaches a maximum after 12 h,and the fouling rate decreases significantly from 12 to 48 h.It gradually stabilizes at 48 to 96 h.With the roughness increasing,the thickness of fouling layer increases,and a linear relationship is presented for 1 to 10 h.By comparing actual and simulated wastewater scaling rates,the relationship between actual and simulated wastewater scaling rates is y=ax-0.494.The composition of the scale was analyzed,calcium carbonate is the main product and increases with fouling time.Based on the above-mentioned results combining literatures,the hybrid prediction model with calcium carbonate as the main product is put forward.It is discussed microscopically that calcium carbonate is converted from aragonite and vaterite in a thermodynamically metastable state to calcite in a thermodynamically stable state.展开更多
Due to the high salt content of coal chemical wastewater,pipeline fouling often occurs during wastewater treatment.Fouling will cause the diameter of the pipe to shrink or even block,which is not conducive to the safe...Due to the high salt content of coal chemical wastewater,pipeline fouling often occurs during wastewater treatment.Fouling will cause the diameter of the pipe to shrink or even block,which is not conducive to the safe and stable operation of the wastewater treatment process.In this paper,the experimental device was designed by using FLUENT software and the fouling deposition mechanisms at different flow velocities and different positions in a 90 deg bend were studied.The experimental results show that when the flow velocity is between 0.2 m·s^(-1) and 0.3 m·s^(-1),the thickness of fouling layer was positively correlated with the flow velocity;when the flow velocity is equal to 0.4 m·s^(-1),the formation of fouling is the most serious;when the flow velocity is between 0.4 m·s^(-1) and 0.7 m·s^(-1),the thickness of fouling layer was negative correlation with the flow velocity;with the increase of inlet velocity,the time for sediment point to develop into sediment surface is shortened.The fouling layer is easy to fall off because of the large shear force on the wall surface of the inner bend of the 90°elbow,so the density of sediment at this position is high.展开更多
[N-(Propionic acid)] terephthalal acyl dihydrazone(H4L) was synthesized and characterized by element analysis,IR,1 H NMR and MS.The theoretical studies on H4L were carried out at HF/6-31+G(d) and B3LYP/6-31+G(d) level...[N-(Propionic acid)] terephthalal acyl dihydrazone(H4L) was synthesized and characterized by element analysis,IR,1 H NMR and MS.The theoretical studies on H4L were carried out at HF/6-31+G(d) and B3LYP/6-31+G(d) levels.The main decomposition stage of it was studied with IR track.The kinetic parameters[the apparent activation energy(E a) and pre-exponential constant(A) of the first and second stages of decomposition reaction] were obtained by Kissinger and Ozawa's methods.Furthermore,the antimicrobial activity of H4L against wheat rust was investigated by spore sprout method.展开更多
An accurate and reliable estimation of minimum miscibility pressure(MMP) of CO2-oil system is a critical task for the design and implementation of CO2 miscible displacement process.In this study,an improved CO2-oil MM...An accurate and reliable estimation of minimum miscibility pressure(MMP) of CO2-oil system is a critical task for the design and implementation of CO2 miscible displacement process.In this study,an improved CO2-oil MMP correlation was developed to predict the MMP values for both pure and impure CO2 injection cases based on ten influential factors,i.e.reservoir temperature(TR),molecular weight of C7+oil components(MWC7+),mole fraction of volatile oil components(xvol),mole fraction of C2-C4 oil components(xC2-C4),mole fraction of C5-C6 oil components(xCs-5-C6),and the gas stream mole fractions of CO2(yCO2),H2S(yH2S),C1(yC1),hydrocarbons(yHC)and N2(yN2).The accuracy of the improved correlation was evaluated against experimental data reported in literature concurrently with those estimated by several renowned correlations.It was found that the improved correlation provided higher prediction accuracy and consistency with literature experimental data than other literature correlations.In addition,the predictive capability of the improved correlation was further validated by predicting an experimentally measured CO2-Oil MMP data,and it showed an accurate result with the absolute deviation of 4.15%.Besides,the differential analysis of the improved correlation was analyzed to estimate the impact of parameters uncertainty in the original MMP data on the calculated results.Also,sensitivity analysis was performed to analyze the influence of each parameter on MMP qualitatively and quantitatively.The results revealed that the increase of xC2-C4,xC5-C6 and yH2 S lead to the decrease of MMP,while the increase of TR,MWC7+,xvol,yCO2,YC1,yHC and yN2 tend to increase the MMP.Overall,the relevance of each parameter with MMP follows the order of TR> xC5-C6> MWC7+> xvol> yH2 S> yHC> yCO2>yC1>yN2>xC2-C4.展开更多
A new complex[Cu_(1.5)(tfc)_(3)(H_(2)O)_(4)]·3H_(2)O (1,Htfc=4-(trifluoro-methyl) nicotinic acid) has been synthesized and characterized by X-ray single-crystal diffraction,elemental analysis,IR spectra and therm...A new complex[Cu_(1.5)(tfc)_(3)(H_(2)O)_(4)]·3H_(2)O (1,Htfc=4-(trifluoro-methyl) nicotinic acid) has been synthesized and characterized by X-ray single-crystal diffraction,elemental analysis,IR spectra and thermogravimetric analysis.1 belongs to orthorhombic system,space group Pccn with a=44.507(2),b=10.7710(6),c=11.7544(7)?,V=5634.9(6)?^(3),Z=1,D_(c)=1.803 mg·cm^(-3),F(000)=3068,μ=1.266 mm^(-1),the final R=0.0488and w R=0.1103 with I>2σ(I).The Cu(II) ion is coordinated by two N and two O atoms from different Htfc as well as two O atoms from two coordinated water molecules,forming a 0D motif with distorted octahedral geometry.The adjacent 0D units are linked into 2D structures through bridge connection coordination mode.In addition,the binding properties of the complex with CT-DNA were investigated by fluorescence and ultraviolet spectra.UVspectra indicate classical intercalation between the complex and CT-DNA.Moreover,the interactions between the ligand and the complex with CT-DNA were studied by Et Br fluorescence probe,which proved that these compounds bind to CT-DNA through an intercalation mode.The binding constants were 0.76 and 1.15 for Htfc and complex 1,which means 1 has stronger interaction with CT-DNA than Htfc.展开更多
基金financially supported by East-West Cooperation Project of Ningxia Key R&D Plan(2017BY064)National First-rate Discipline Construction Project of Ningxia(NXYLXK2017A04)。
文摘Zero liquid discharge(ZLD)treatment and reuse equipment of high salinity wastewater in coal-chemical industry often occur in various types of blockage problems because of high salt content,affecting the long-term stability of the device.In this study,the effects of solution temperature,steel,reaction time and wall roughness on fouling were investigated.The changes in the contents of fouling and fouling substances were qualitatively and quantitatively analyzed by XRD and EDS respectively,and the formation of scale was observed by SEM.The results show that with temperature increasing,Q235 steel is the most difficult to scale.Scaling rate of all salt scales reaches a maximum after 12 h,and the fouling rate decreases significantly from 12 to 48 h.It gradually stabilizes at 48 to 96 h.With the roughness increasing,the thickness of fouling layer increases,and a linear relationship is presented for 1 to 10 h.By comparing actual and simulated wastewater scaling rates,the relationship between actual and simulated wastewater scaling rates is y=ax-0.494.The composition of the scale was analyzed,calcium carbonate is the main product and increases with fouling time.Based on the above-mentioned results combining literatures,the hybrid prediction model with calcium carbonate as the main product is put forward.It is discussed microscopically that calcium carbonate is converted from aragonite and vaterite in a thermodynamically metastable state to calcite in a thermodynamically stable state.
基金financially supported by the Natural Science Foundation of Ningxia Hui Autonomous Region(2020AAC03025)Undergraduate Training Programs for Innovation(2019107490001)+1 种基金East-West Cooperation Project of Ningxia Key R&D Plan(2017BY064)National First-rate Discipline Construction Project of Ningxia(NXYLXK2017A04)。
文摘Due to the high salt content of coal chemical wastewater,pipeline fouling often occurs during wastewater treatment.Fouling will cause the diameter of the pipe to shrink or even block,which is not conducive to the safe and stable operation of the wastewater treatment process.In this paper,the experimental device was designed by using FLUENT software and the fouling deposition mechanisms at different flow velocities and different positions in a 90 deg bend were studied.The experimental results show that when the flow velocity is between 0.2 m·s^(-1) and 0.3 m·s^(-1),the thickness of fouling layer was positively correlated with the flow velocity;when the flow velocity is equal to 0.4 m·s^(-1),the formation of fouling is the most serious;when the flow velocity is between 0.4 m·s^(-1) and 0.7 m·s^(-1),the thickness of fouling layer was negative correlation with the flow velocity;with the increase of inlet velocity,the time for sediment point to develop into sediment surface is shortened.The fouling layer is easy to fall off because of the large shear force on the wall surface of the inner bend of the 90°elbow,so the density of sediment at this position is high.
基金Supported by the Shaanxi Provincial Project of the Technology and Plan,China(No.2007K02-11)the Project of Education Committee of Shaanxi Province,China(No.2011JG04)the Shaanxi Provincial Science and Technology Project,China(No.08ZDKG-268)
文摘[N-(Propionic acid)] terephthalal acyl dihydrazone(H4L) was synthesized and characterized by element analysis,IR,1 H NMR and MS.The theoretical studies on H4L were carried out at HF/6-31+G(d) and B3LYP/6-31+G(d) levels.The main decomposition stage of it was studied with IR track.The kinetic parameters[the apparent activation energy(E a) and pre-exponential constant(A) of the first and second stages of decomposition reaction] were obtained by Kissinger and Ozawa's methods.Furthermore,the antimicrobial activity of H4L against wheat rust was investigated by spore sprout method.
基金The financial supports from the Scientific research start-up funding of Zhoukou Normal University (ZKNUC2016022)National Natural Science Foundation of China (21536003, 21706057, and 21606078)the Natural Science Foundation of Guangxi Province (2016GXNSFAA380190) are gratefully acknowledged
文摘An accurate and reliable estimation of minimum miscibility pressure(MMP) of CO2-oil system is a critical task for the design and implementation of CO2 miscible displacement process.In this study,an improved CO2-oil MMP correlation was developed to predict the MMP values for both pure and impure CO2 injection cases based on ten influential factors,i.e.reservoir temperature(TR),molecular weight of C7+oil components(MWC7+),mole fraction of volatile oil components(xvol),mole fraction of C2-C4 oil components(xC2-C4),mole fraction of C5-C6 oil components(xCs-5-C6),and the gas stream mole fractions of CO2(yCO2),H2S(yH2S),C1(yC1),hydrocarbons(yHC)and N2(yN2).The accuracy of the improved correlation was evaluated against experimental data reported in literature concurrently with those estimated by several renowned correlations.It was found that the improved correlation provided higher prediction accuracy and consistency with literature experimental data than other literature correlations.In addition,the predictive capability of the improved correlation was further validated by predicting an experimentally measured CO2-Oil MMP data,and it showed an accurate result with the absolute deviation of 4.15%.Besides,the differential analysis of the improved correlation was analyzed to estimate the impact of parameters uncertainty in the original MMP data on the calculated results.Also,sensitivity analysis was performed to analyze the influence of each parameter on MMP qualitatively and quantitatively.The results revealed that the increase of xC2-C4,xC5-C6 and yH2 S lead to the decrease of MMP,while the increase of TR,MWC7+,xvol,yCO2,YC1,yHC and yN2 tend to increase the MMP.Overall,the relevance of each parameter with MMP follows the order of TR> xC5-C6> MWC7+> xvol> yH2 S> yHC> yCO2>yC1>yN2>xC2-C4.
基金Supported by the National Natural Science Foundation of China (No. 21763022)。
文摘A new complex[Cu_(1.5)(tfc)_(3)(H_(2)O)_(4)]·3H_(2)O (1,Htfc=4-(trifluoro-methyl) nicotinic acid) has been synthesized and characterized by X-ray single-crystal diffraction,elemental analysis,IR spectra and thermogravimetric analysis.1 belongs to orthorhombic system,space group Pccn with a=44.507(2),b=10.7710(6),c=11.7544(7)?,V=5634.9(6)?^(3),Z=1,D_(c)=1.803 mg·cm^(-3),F(000)=3068,μ=1.266 mm^(-1),the final R=0.0488and w R=0.1103 with I>2σ(I).The Cu(II) ion is coordinated by two N and two O atoms from different Htfc as well as two O atoms from two coordinated water molecules,forming a 0D motif with distorted octahedral geometry.The adjacent 0D units are linked into 2D structures through bridge connection coordination mode.In addition,the binding properties of the complex with CT-DNA were investigated by fluorescence and ultraviolet spectra.UVspectra indicate classical intercalation between the complex and CT-DNA.Moreover,the interactions between the ligand and the complex with CT-DNA were studied by Et Br fluorescence probe,which proved that these compounds bind to CT-DNA through an intercalation mode.The binding constants were 0.76 and 1.15 for Htfc and complex 1,which means 1 has stronger interaction with CT-DNA than Htfc.
基金This work was supported by the National Natural Science Foundation of China(51871137,51901118,51571136 and 61904099).The authors acknowledge Shanghai Synchrotron Radiation Facility at the Beamline BL08U1A and the National Synchrotron Radiation Laboratory at the Beamline BL12-a for the XAS measurements.
