In order to better understand the prevailing mechanism of CO2 storage in coal and estimate CO2 sequestration capacity of a coal seam and enhanced coalbed methane recovery (ECBM) with CO2 injection into coal, we inve...In order to better understand the prevailing mechanism of CO2 storage in coal and estimate CO2 sequestration capacity of a coal seam and enhanced coalbed methane recovery (ECBM) with CO2 injection into coal, we investigated the preferential adsorption of CH4 and CO2 on coals. Adsorption of pure CO2, CH4 and their binary mixtures on high-rank coals from Qinshui Basin in China were employed to study the preferential adsorption behaviour. Multiple regression equations were presented to predict CH4 equi- librium concentration from equilibrium pressure and its initial-composition in feed gas. The results show that preferential adsorption of CO2 on coals over the entire pressure range under competitive sorption conditions was observed, however, preferential adsorption of CH4 over CO2 on low-volatile bituminous coal from higher CH4-compostion in source gas was found at up to 1O MPa pressure. Preferential adsorp- tion of CO2 increases with increase of CH4 concentration in source gas, and decreases with increasing pressure. Although there was no systematic investigation of the effect of coal rank on preferential adsorp- tion, there are obvious differences in preferential adsorption of gas between low-volatile bituminous coal and anthracite. The obtained preferential adsorption gives rise to the assumption that CO2 sequestration in coal beds with subsequent CO2-ECBM might be an ootion in Qinshui Basins, China.展开更多
In order to explore the influence of Cu element on the morphology evolution of the in-situ TiB2 particles, the10 wt.% TiB2 reinforced Al-5 wt.%Cu based composite was prepared by mixed salt casting. The morphology char...In order to explore the influence of Cu element on the morphology evolution of the in-situ TiB2 particles, the10 wt.% TiB2 reinforced Al-5 wt.%Cu based composite was prepared by mixed salt casting. The morphology characterization and transformation of TiB2 reinforcements caused by Cu element were investigated by multi-scale microstructure characterization and statistics techniques. In the case of controlled casting, 5 wt.% Cu addition was found to transform the TiB2 particle morphology from hexagonal plate with sharp edges and corners to hexagonal or tetragonal prism with chamfered edges and corners with the distinguishing growth steps both on the top surface and the side surface. The TiB2 growth in Al-Cu matrix followed the rules: nano-scaled spherical nuclei-polyhedron grains-chamfered hexagonal particles-hexagonal plates-chamfered particles with obvious growth steps. The adsorption energy of Cu on different crystal surfaces of TiB2 was caculated to reveal the influence mechanism and the results indicated that Cu was preferentially adsorbed on the(10-11)TiB2 crystal planes, devoting to the small aspect ratio of TiB2.展开更多
In order to realize the sulfur and water resistance and facilitate the CO oxidation reactions,the effects of strain on the adsorption of CO,O_(2),SO_(2)and H_(2)O molecules on Ni single-atom-catalyst supported by sing...In order to realize the sulfur and water resistance and facilitate the CO oxidation reactions,the effects of strain on the adsorption of CO,O_(2),SO_(2)and H_(2)O molecules on Ni single-atom-catalyst supported by single-carbon-vacancy graphene(Ni-SG) have been studied based on first principles calculations.It shows that the compressive strain increases the adsorption energies of all above mentioned molecules on Ni-SG,where SO_(2)is adsorbed more strongly on Ni-SG than CO.However,in the presence of tensile strain,the adsorption energies decreases significantly when the molecules(O_(2)and SO_(2)) obtain electrons from NiSG,while the adsorption energies just slightly decrease when the molecules(CO and H_(2)O) lose electrons to Ni-SG,which finally achieves the preferential adsorption of CO and O_(2)molecules on Ni-SG by tensile strain.In addition,with tensile strain increasing to 10%,the rate-limited energy barrier along Eley-Rideal(ER) path monotonically increases from 0.77 eV to 0.98 eV,while the rate-limited energy barrier along Langmuir-Hinshelwood(LH) path monotonically decreases from 0.54 eV to 0.44 eV,indicating that the tensile strain can facilitate the LH mechanism while imped the ER mechanism on Ni-SG.The Hirshfeld charge and orbital levels of O_(2)and CO molecules are modulated by the tensile strain,which plays an important role for the decreasing of energy barriers for CO oxidation.Overall,the tensile strain can enhance the sulfur and water resistance of Ni-SG,as well as boost the CO oxidation reactions.展开更多
The equilibrium and dynamic surface tension (DST) of the novel cationic surfactant, 3-(p-nonylphenoxy)-2-hydroxylpropyl trimethyl ammonium bromide, abbreviated as RTAB, were studied. The effect of sodium halide su...The equilibrium and dynamic surface tension (DST) of the novel cationic surfactant, 3-(p-nonylphenoxy)-2-hydroxylpropyl trimethyl ammonium bromide, abbreviated as RTAB, were studied. The effect of sodium halide such as NaCl, NaBr and NaI on the DST behavior of the RTAB solution below its CMC was studied in detail. Due to the preferential adsorption, the effect of hydration and salting out, the ability to reduce the DST values at the same concentration was in the order of NaI〉NaBr〉NaCl. Attributed to its high surface activity, the equilibrium time of the DST of the surfactant solution was insensitive to the ionic strength.展开更多
Cadmium-bearing nanoparticles,such as nanoparticulate cadmium selenide(CdSe)and cadmium sulfide(CdS),widely exist in the environment and originate from both natural and anthropogenic sources.Risk assessment of these n...Cadmium-bearing nanoparticles,such as nanoparticulate cadmium selenide(CdSe)and cadmium sulfide(CdS),widely exist in the environment and originate from both natural and anthropogenic sources.Risk assessment of these nanoparticles cannot be accurate without taking into account the properties of the protein corona that is acquired by the nanoparticles upon biouptake.Here,we show that the compositions of the protein corona on CdSe/CdS nanoparticles are regulated collectively by the surface atomic arrangement of the nanoparticles and the abundance and distribution of cysteine moieties of the proteins in contact with the nanoparticles.A proteomic analysis shows that the observed facet-dependent preferential binding of proteins is mostly related to the cysteine contents of the proteins,among commonly recognized protein properties controlling the formation of the protein corona.Theoretical calculations further demonstrate that the atomic arrangement of surface Cd atoms,as dictated by the exposed facets of the nanoparticles,controls the specific binding mode of the S atoms in the disulfide bonds of the proteins.Supplemental protein adsorption experiments confirm that disulfide bonds remain intact during protein adsorption,making the binding of protein molecules sensitive to the abundance and distribution of Cd-binding moieties and possibly molecular rigidity of the proteins.The significant conformational changes of adsorbed proteins evidenced from a circular dichroism spectroscopy analysis suggest that disrupting the structural stability of proteins may be an additional risk factor of Cd-bearing nanoparticles.These findings underline that the unique properties and behaviors of nanoparticles must be fully considered when evaluating the biological effects and health risks of metal pollutants.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51174127 and 21176145)the Natural Science Foundation of Shandong Province(No.ZR2011DM005)the Open Research Fund Program of Key Laboratory of Mine Disaster Prevention and Control(Shandong University of Science and Technology)(No.MDPC0806)
文摘In order to better understand the prevailing mechanism of CO2 storage in coal and estimate CO2 sequestration capacity of a coal seam and enhanced coalbed methane recovery (ECBM) with CO2 injection into coal, we investigated the preferential adsorption of CH4 and CO2 on coals. Adsorption of pure CO2, CH4 and their binary mixtures on high-rank coals from Qinshui Basin in China were employed to study the preferential adsorption behaviour. Multiple regression equations were presented to predict CH4 equi- librium concentration from equilibrium pressure and its initial-composition in feed gas. The results show that preferential adsorption of CO2 on coals over the entire pressure range under competitive sorption conditions was observed, however, preferential adsorption of CH4 over CO2 on low-volatile bituminous coal from higher CH4-compostion in source gas was found at up to 1O MPa pressure. Preferential adsorp- tion of CO2 increases with increase of CH4 concentration in source gas, and decreases with increasing pressure. Although there was no systematic investigation of the effect of coal rank on preferential adsorp- tion, there are obvious differences in preferential adsorption of gas between low-volatile bituminous coal and anthracite. The obtained preferential adsorption gives rise to the assumption that CO2 sequestration in coal beds with subsequent CO2-ECBM might be an ootion in Qinshui Basins, China.
基金Project(2017YFB110400)supported by the National Key Research and Development Program of China。
文摘In order to explore the influence of Cu element on the morphology evolution of the in-situ TiB2 particles, the10 wt.% TiB2 reinforced Al-5 wt.%Cu based composite was prepared by mixed salt casting. The morphology characterization and transformation of TiB2 reinforcements caused by Cu element were investigated by multi-scale microstructure characterization and statistics techniques. In the case of controlled casting, 5 wt.% Cu addition was found to transform the TiB2 particle morphology from hexagonal plate with sharp edges and corners to hexagonal or tetragonal prism with chamfered edges and corners with the distinguishing growth steps both on the top surface and the side surface. The TiB2 growth in Al-Cu matrix followed the rules: nano-scaled spherical nuclei-polyhedron grains-chamfered hexagonal particles-hexagonal plates-chamfered particles with obvious growth steps. The adsorption energy of Cu on different crystal surfaces of TiB2 was caculated to reveal the influence mechanism and the results indicated that Cu was preferentially adsorbed on the(10-11)TiB2 crystal planes, devoting to the small aspect ratio of TiB2.
基金support by the Fundamental Research Funds for the Central Universities (No. B210202099)National Natural Science Foundation of China (Nos. 21703052, 22176041, 21777033)Science and Technology Planning Project of Guangdong Province (No. 2017B020216003)。
文摘In order to realize the sulfur and water resistance and facilitate the CO oxidation reactions,the effects of strain on the adsorption of CO,O_(2),SO_(2)and H_(2)O molecules on Ni single-atom-catalyst supported by single-carbon-vacancy graphene(Ni-SG) have been studied based on first principles calculations.It shows that the compressive strain increases the adsorption energies of all above mentioned molecules on Ni-SG,where SO_(2)is adsorbed more strongly on Ni-SG than CO.However,in the presence of tensile strain,the adsorption energies decreases significantly when the molecules(O_(2)and SO_(2)) obtain electrons from NiSG,while the adsorption energies just slightly decrease when the molecules(CO and H_(2)O) lose electrons to Ni-SG,which finally achieves the preferential adsorption of CO and O_(2)molecules on Ni-SG by tensile strain.In addition,with tensile strain increasing to 10%,the rate-limited energy barrier along Eley-Rideal(ER) path monotonically increases from 0.77 eV to 0.98 eV,while the rate-limited energy barrier along Langmuir-Hinshelwood(LH) path monotonically decreases from 0.54 eV to 0.44 eV,indicating that the tensile strain can facilitate the LH mechanism while imped the ER mechanism on Ni-SG.The Hirshfeld charge and orbital levels of O_(2)and CO molecules are modulated by the tensile strain,which plays an important role for the decreasing of energy barriers for CO oxidation.Overall,the tensile strain can enhance the sulfur and water resistance of Ni-SG,as well as boost the CO oxidation reactions.
基金Project supported by the National Natural Science Foundation of China (No. 50472069) and the Ministry of Science and Technology of China (Nos. G2000078104 and 2003CCA02900).
文摘The equilibrium and dynamic surface tension (DST) of the novel cationic surfactant, 3-(p-nonylphenoxy)-2-hydroxylpropyl trimethyl ammonium bromide, abbreviated as RTAB, were studied. The effect of sodium halide such as NaCl, NaBr and NaI on the DST behavior of the RTAB solution below its CMC was studied in detail. Due to the preferential adsorption, the effect of hydration and salting out, the ability to reduce the DST values at the same concentration was in the order of NaI〉NaBr〉NaCl. Attributed to its high surface activity, the equilibrium time of the DST of the surfactant solution was insensitive to the ionic strength.
基金supported by the National Natural Science Foundation of China(22125603,22276211,and 22193051)Tianjin Municipal Science and Technology Commission(21JCJQJC00060).
文摘Cadmium-bearing nanoparticles,such as nanoparticulate cadmium selenide(CdSe)and cadmium sulfide(CdS),widely exist in the environment and originate from both natural and anthropogenic sources.Risk assessment of these nanoparticles cannot be accurate without taking into account the properties of the protein corona that is acquired by the nanoparticles upon biouptake.Here,we show that the compositions of the protein corona on CdSe/CdS nanoparticles are regulated collectively by the surface atomic arrangement of the nanoparticles and the abundance and distribution of cysteine moieties of the proteins in contact with the nanoparticles.A proteomic analysis shows that the observed facet-dependent preferential binding of proteins is mostly related to the cysteine contents of the proteins,among commonly recognized protein properties controlling the formation of the protein corona.Theoretical calculations further demonstrate that the atomic arrangement of surface Cd atoms,as dictated by the exposed facets of the nanoparticles,controls the specific binding mode of the S atoms in the disulfide bonds of the proteins.Supplemental protein adsorption experiments confirm that disulfide bonds remain intact during protein adsorption,making the binding of protein molecules sensitive to the abundance and distribution of Cd-binding moieties and possibly molecular rigidity of the proteins.The significant conformational changes of adsorbed proteins evidenced from a circular dichroism spectroscopy analysis suggest that disrupting the structural stability of proteins may be an additional risk factor of Cd-bearing nanoparticles.These findings underline that the unique properties and behaviors of nanoparticles must be fully considered when evaluating the biological effects and health risks of metal pollutants.