The catalytic hydrolysis of dichlorodifluoromethane (CFC-12) was investigated over solid acid Ti(SO_4)_2. The catalytic activity decreased with the calcination temperature. When space velocity was 6 1 h^(-1) g-cat^(-1...The catalytic hydrolysis of dichlorodifluoromethane (CFC-12) was investigated over solid acid Ti(SO_4)_2. The catalytic activity decreased with the calcination temperature. When space velocity was 6 1 h^(-1) g-cat^(-1). the CPC-12 conversion at 310C over Ti(SO_4)_2 calcined at 350C remained about 98.5% during 360 h on stream. and the selectivity to by-products remained zero. The findings enlarged the scope of traditional catalyst systems for the CFCs decomposition.展开更多
Highly active solid superacid catalysts for n-butane isomerization, SZ/A1_2O_3-P, were prepared by supporting SO-(4-2)/ZrO2, (SZ) on y-A1_2O_3 carrier using a precipitation method. The activities of some catalysts wer...Highly active solid superacid catalysts for n-butane isomerization, SZ/A1_2O_3-P, were prepared by supporting SO-(4-2)/ZrO2, (SZ) on y-A1_2O_3 carrier using a precipitation method. The activities of some catalysts were enhanced significantly j The activity of the most active sample. 60%SZ/Al_2O3-P, was even about 2 times more active than that of the SZ catalyst.展开更多
The 2024 anodized aluminum alloy film was sealed by KAl(SO_(4))_(2)solution and the effect of sealing on corrosion resistance was investigated by means of potentiodynamic polarization curves,electrochemical impedance ...The 2024 anodized aluminum alloy film was sealed by KAl(SO_(4))_(2)solution and the effect of sealing on corrosion resistance was investigated by means of potentiodynamic polarization curves,electrochemical impedance spectroscopy,and X-ray photoelectron spectroscopy.The experimental results show that the optimal parameters for KAl(SO_(4))_(2)sealing are 35℃,with the pH value of 8,the concentration of 8 g/L,and the sealing time of 3 min.The corrosion resistance of the KAl(SO_(4))_(2)sealed sample can be significantly improved than that of unsealed one,and is obviously superior to that of the conventional hydrothermal sealed sample.Furthermore,X-ray photoelectron spectroscopy demonstrates that more Al(OH)_(3)will be formed in the process of KAl(SO_(4))_(2)sealing,which will shrink the diameter of the microporous and therefore results in the excellent corrosion resistance.展开更多
In this study,the benign target double terpyridine parts based amphiphilic ionic molecules(AIMs 1,2)and the reference single terpyridine segment included AIMs(AIMs 3,4)were synthesized through a multi-step method,and ...In this study,the benign target double terpyridine parts based amphiphilic ionic molecules(AIMs 1,2)and the reference single terpyridine segment included AIMs(AIMs 3,4)were synthesized through a multi-step method,and the molecular structures were fully characterized.The excellent anticorrosion of the target AIMs for copper surface in H_(2)SO_(4) solution was demonstrated by the electrochemistry analysis,which was more superior over those of the reference AIMs.The standard adsorption free energy changes of the target AIMs calculated by the adsorption isotherms were lower than -40 kJ·mol^(-1),suggesting an intensified chemical adsorption on metal surface.The molecular modeling and molecular dynamic computation of the studied AIMs were performed,demonstrating that the target AIMs exhibited lower highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps and greater adsorption energies than the reference ones.The chemical adsorption of the AIMs on metal surface was revealed by various spectroscopic methods including scanning electron microscopy,atomic force microscopy,Fourier transform infrared spectroscopy,attenuated total reflection infrared spectroscopy,Raman and X-ray diffraction.展开更多
Novel magnetic nanoparticles(MNPs),Fe_(3)O_(4)@SiO_(2) and Fe_(3)O_(4)@SiO_(2)@PEG-(COOH)_(2),were prepared by loading different amounts of SiO_(2) or/and PEG-(COOH)_(2) onto Fe_(3)O_(4) nanoparticles,and their feasib...Novel magnetic nanoparticles(MNPs),Fe_(3)O_(4)@SiO_(2) and Fe_(3)O_(4)@SiO_(2)@PEG-(COOH)_(2),were prepared by loading different amounts of SiO_(2) or/and PEG-(COOH)_(2) onto Fe_(3)O_(4) nanoparticles,and their feasibility to be used as forward osmosis(FO)draw solutes was investigated.The characterization of the materials showed that,compared to normal Fe_(3)O_(4) nanoparticles,the modified MNPs exhibited enhanced dispersity and high osmotic pressure in aqueous solution.The FO experiment indicated that the synthesized draw solutes could obtain a water flux as high as 10 L·m^(-2)·h^(-1) with an aquaporin FO membrane.The optimal concentration of the added tetraethyl orthosilicate was 30%during the synthesis.The novel MNPs could be easily recovered from draw solutions by magnetic field,and the recovery rate of Fe_(3)O_(4)@SiO_(2) and Fe_(3)O_(4)@SiO_(2)@PEG-(COOH)_(2) was 83.95%and 63.37%,respectively.Moreover,after 5 recycles of reuse,the water flux of Fe_(3)O_(4)@SiO_(2) and Fe_(3)O_(4)@SiO_(2)@PEG-(COOH)_(2) as draw solutes still remained 64.36%and 85.26%,respectively.The experimental results demonstrated that the synthesized core–shell magnetic nanoparticles are promising draw solutes,and the Fe_(3)O_(4)@SiO_(2)@PEG-(COOH)_(2) was more suitable to be used as draw solute in FO process.展开更多
A series of tungstate red phosphors K_(1-x)Li_(x)Eu(WO_(4))_(2-y)(SO_(4))_(y)were successfully prepared by sol-gel method,and the effects of the introduction of Li^(+)and SO_(4)^(2-)on the fluorescence intensity and t...A series of tungstate red phosphors K_(1-x)Li_(x)Eu(WO_(4))_(2-y)(SO_(4))_(y)were successfully prepared by sol-gel method,and the effects of the introduction of Li^(+)and SO_(4)^(2-)on the fluorescence intensity and thermal quenching properties of the prepared K_(1-x)Li_(x)Eu(WO_(4))_(2-y)(SO_(4))_(y)phosphors were investigated.The X-ray diffraction data show that the prepared(Li^(+)and SO_(4)^(2-))-doped KEu(WO_(4))_(2)phosphors have a monoclinic tetragonal structure.In addition,the emission intensities of all the observed emission peaks change significantly with the increase of Li~+doping concentration,especially the intensity of the emission peaks at 615 nm fluctuated significantly and reached the maximum at x=0.3 and y=0.2.The K_(1-x)Li_(x)Eu(WO_(4))_(2-y)(SO_(4))_(y)phosphors are found to have the highest fluorescence intensity at x=0.3 and y=0.2.Moreover,the K_(0.7)Li_(0.3)Eu(WO_(4))_(1.8)(SO_(4))_(0.2)phosphor has better thermal quenching properties and luminescence efficiency,and the experimental results indicates that the fluorescence intensity and thermal burst performance of KEu(WO_(4))_(2)red phosphor could be effectively improved by using low-cost bionic doping of Li^(+)and SO_(4)^(2-).展开更多
文摘The catalytic hydrolysis of dichlorodifluoromethane (CFC-12) was investigated over solid acid Ti(SO_4)_2. The catalytic activity decreased with the calcination temperature. When space velocity was 6 1 h^(-1) g-cat^(-1). the CPC-12 conversion at 310C over Ti(SO_4)_2 calcined at 350C remained about 98.5% during 360 h on stream. and the selectivity to by-products remained zero. The findings enlarged the scope of traditional catalyst systems for the CFCs decomposition.
文摘Highly active solid superacid catalysts for n-butane isomerization, SZ/A1_2O_3-P, were prepared by supporting SO-(4-2)/ZrO2, (SZ) on y-A1_2O_3 carrier using a precipitation method. The activities of some catalysts were enhanced significantly j The activity of the most active sample. 60%SZ/Al_2O3-P, was even about 2 times more active than that of the SZ catalyst.
基金Funded by the National Natural Science Foundation of China(No.12175107)the Natural Science Foundation of Nanjing University of Posts and Telecommunications(No.NY220030)
文摘The 2024 anodized aluminum alloy film was sealed by KAl(SO_(4))_(2)solution and the effect of sealing on corrosion resistance was investigated by means of potentiodynamic polarization curves,electrochemical impedance spectroscopy,and X-ray photoelectron spectroscopy.The experimental results show that the optimal parameters for KAl(SO_(4))_(2)sealing are 35℃,with the pH value of 8,the concentration of 8 g/L,and the sealing time of 3 min.The corrosion resistance of the KAl(SO_(4))_(2)sealed sample can be significantly improved than that of unsealed one,and is obviously superior to that of the conventional hydrothermal sealed sample.Furthermore,X-ray photoelectron spectroscopy demonstrates that more Al(OH)_(3)will be formed in the process of KAl(SO_(4))_(2)sealing,which will shrink the diameter of the microporous and therefore results in the excellent corrosion resistance.
基金the National Natural Science Foundation of China (21376282,21676035,21878029)Chongqing Science and Technology Commission (cstc2018jcyjAX0668)+2 种基金Shandong Province Natural Science Foundation (ZR2020QB18)China Postdoctoral Science Foundation (22012 T50762&2011 M501388)Graduate Student Research Innovation Project,Chongqing University (CYB18046)。
文摘In this study,the benign target double terpyridine parts based amphiphilic ionic molecules(AIMs 1,2)and the reference single terpyridine segment included AIMs(AIMs 3,4)were synthesized through a multi-step method,and the molecular structures were fully characterized.The excellent anticorrosion of the target AIMs for copper surface in H_(2)SO_(4) solution was demonstrated by the electrochemistry analysis,which was more superior over those of the reference AIMs.The standard adsorption free energy changes of the target AIMs calculated by the adsorption isotherms were lower than -40 kJ·mol^(-1),suggesting an intensified chemical adsorption on metal surface.The molecular modeling and molecular dynamic computation of the studied AIMs were performed,demonstrating that the target AIMs exhibited lower highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps and greater adsorption energies than the reference ones.The chemical adsorption of the AIMs on metal surface was revealed by various spectroscopic methods including scanning electron microscopy,atomic force microscopy,Fourier transform infrared spectroscopy,attenuated total reflection infrared spectroscopy,Raman and X-ray diffraction.
文摘Novel magnetic nanoparticles(MNPs),Fe_(3)O_(4)@SiO_(2) and Fe_(3)O_(4)@SiO_(2)@PEG-(COOH)_(2),were prepared by loading different amounts of SiO_(2) or/and PEG-(COOH)_(2) onto Fe_(3)O_(4) nanoparticles,and their feasibility to be used as forward osmosis(FO)draw solutes was investigated.The characterization of the materials showed that,compared to normal Fe_(3)O_(4) nanoparticles,the modified MNPs exhibited enhanced dispersity and high osmotic pressure in aqueous solution.The FO experiment indicated that the synthesized draw solutes could obtain a water flux as high as 10 L·m^(-2)·h^(-1) with an aquaporin FO membrane.The optimal concentration of the added tetraethyl orthosilicate was 30%during the synthesis.The novel MNPs could be easily recovered from draw solutions by magnetic field,and the recovery rate of Fe_(3)O_(4)@SiO_(2) and Fe_(3)O_(4)@SiO_(2)@PEG-(COOH)_(2) was 83.95%and 63.37%,respectively.Moreover,after 5 recycles of reuse,the water flux of Fe_(3)O_(4)@SiO_(2) and Fe_(3)O_(4)@SiO_(2)@PEG-(COOH)_(2) as draw solutes still remained 64.36%and 85.26%,respectively.The experimental results demonstrated that the synthesized core–shell magnetic nanoparticles are promising draw solutes,and the Fe_(3)O_(4)@SiO_(2)@PEG-(COOH)_(2) was more suitable to be used as draw solute in FO process.
基金Funded by the Science and Technology Bureau of Chengdu City(No.2022-YF05-02119-SN)。
文摘A series of tungstate red phosphors K_(1-x)Li_(x)Eu(WO_(4))_(2-y)(SO_(4))_(y)were successfully prepared by sol-gel method,and the effects of the introduction of Li^(+)and SO_(4)^(2-)on the fluorescence intensity and thermal quenching properties of the prepared K_(1-x)Li_(x)Eu(WO_(4))_(2-y)(SO_(4))_(y)phosphors were investigated.The X-ray diffraction data show that the prepared(Li^(+)and SO_(4)^(2-))-doped KEu(WO_(4))_(2)phosphors have a monoclinic tetragonal structure.In addition,the emission intensities of all the observed emission peaks change significantly with the increase of Li~+doping concentration,especially the intensity of the emission peaks at 615 nm fluctuated significantly and reached the maximum at x=0.3 and y=0.2.The K_(1-x)Li_(x)Eu(WO_(4))_(2-y)(SO_(4))_(y)phosphors are found to have the highest fluorescence intensity at x=0.3 and y=0.2.Moreover,the K_(0.7)Li_(0.3)Eu(WO_(4))_(1.8)(SO_(4))_(0.2)phosphor has better thermal quenching properties and luminescence efficiency,and the experimental results indicates that the fluorescence intensity and thermal burst performance of KEu(WO_(4))_(2)red phosphor could be effectively improved by using low-cost bionic doping of Li^(+)and SO_(4)^(2-).
