Five corrosion inhibitors have been evaluated in high temperature naphthenic acid environment: triethyl phosphate(A), dioctylphosphoric acid(B), triphenyl phosphate(C), tetraethylenepentamine(D) and 1 aminoethyl 2 dod...Five corrosion inhibitors have been evaluated in high temperature naphthenic acid environment: triethyl phosphate(A), dioctylphosphoric acid(B), triphenyl phosphate(C), tetraethylenepentamine(D) and 1 aminoethyl 2 dodecylimidazoline(E). It is found that A, B and C have good inhibitory property and the corrosion inhibitory efficiency increases linearly with the hydrophilicity of inhibitor molecule; polyamine compound, being a corrosion inhibitor, reacts also with naphthenic acid to produce azole or amide compounds, which also behave as inhibitors.展开更多
Fifty-three samples of multi-substituted benzylideneanilines XArCH=NArYs （abbreviated XBAYs） were synthesized and their NMR spectra were determined. An extensional study of substituent effects on the 1H NMR chemical...Fifty-three samples of multi-substituted benzylideneanilines XArCH=NArYs （abbreviated XBAYs） were synthesized and their NMR spectra were determined. An extensional study of substituent effects on the 1H NMR chemical shifts （δH（CH=N）） and 13C NMR chemical shifts （δc（CH=N）） of the CH=N bridging group from di-substituted to multi-substituted XBAYs was made based on a total of 182 samples of XBAYs, together with the NMR data of other 129 samples of di-substituted XBAYs quoted from literatures. The results show thatthe substituent specific cross-interaction effect parameter （△（∑σ）2） plays an important role in quantifying the δc（CH=N） values of XBAYs, but it is negligible for quantifying the δH （CH=N） values; the other substituent parameters also present different influences on the δc （CH=N） and （δH （CH=N）. On the whole, the contributions of X and Y to the δc （CH=N） of XBAYs are balanced, but the δH（CH=N） values of XBAYs mainly rely on the contributions of X.展开更多
In recent years,environmental pollution and energy crisis have become increasingly serious issues owing to the burning of fossil fuels.Among the many technologies,decomposition of water to produce hydrogen has attract...In recent years,environmental pollution and energy crisis have become increasingly serious issues owing to the burning of fossil fuels.Among the many technologies,decomposition of water to produce hydrogen has attracted much attention because of its sustainability and non-polluting characteristic.However,highly efficient decomposition of water that is driven by visible light is still a challenge.Herein,we report the large-scale preparation of step-scheme porous graphite carbon nitride/Zn0.2Cd0.8S-diethylenetriamine(Pg-C3N4/Zn0.2Cd0.8S-DETA)composite by a facile solvothermal method.It was found by UV-vis spectroscopy that 15%Pg-C3N4/Zn0.2Cd0.8S-DETA exhibited suitable visible absorption edge and band gap for water decomposition.The hydrogen production rate of 15%Pg-C3N4/Zn0.2Cd0.8S-DETA composite was 6.69 mmol g^-1 h^-1,which was 16.73,1.61,and 1.44 times greater than those of Pg-C3N4,CdS-DETA,and Zn0.2Cd0.8S-DETA,respectively.In addition,15%Pg-C3N4/Zn0.2Cd0.8S-DETA composite displayed excellent photocatalytic stability,which was maintained for seven cycles of photocatalytic water splitting test.We believe that 15%Pg-C3N4/Zn0.2Cd0.8S-DETA composite can be a valuable guide for the development of solar hydrogen production applications in the near future.展开更多
The development of heterogeneous catalytic processes is crucial for the synthesis of chiral compounds for both academic and industrial applications.However,thus far,such achievements have remained elusive.Herein,we re...The development of heterogeneous catalytic processes is crucial for the synthesis of chiral compounds for both academic and industrial applications.However,thus far,such achievements have remained elusive.Herein,we report the heterogeneous asymmetric hydrogenation of 2-methylquinoline over solid chiral catalysts,which were prepared by the one-pot polymerization of(1R,2R)-N-(4-vinyl-benzenesulfonyl)-1,2-diphenylethane-1,2-diamine(VDPEN)and divinylbenzene(DVB)in the presence or absence of activated carbon(C)or carbon nanotubes(CNTs),followed by Ru coordination and anion exchange.The solid chiral catalysts were fully characterized by N2 sorption analysis,elemental analysis,TEM,FT-IR spectroscopy,and 13C CP-MAS NMR.All the solid chiral catalysts could efficiently catalyze the asymmetric hydrogenation of 2-methylquinoline to afford 2-methyl-1,2,3,4-tetrahydroquinoline with 90%ee.Studies have shown that polymer/C and polymer/CNTs composites are more active than pure polymers.The polymer/CNTs composite exhibited the highest activity among all the solid chiral catalysts under identical conditions,owing to the unique morphology of CNTs.The recycling stabilities of the solid chiral catalysts were greatly improved when ionic liquids(ILs)were employed as solvents;this is mainly attributed to the decreased leaching amount of anions owing to the confinement effect of ILs on ionic compounds.展开更多
Due to its high energy density,lithium-sulfur(Li-S)battery is considered as the most promising candidate for the energy storage systems,but its practical application is hindered by the dissolution of lithium polysulfi...Due to its high energy density,lithium-sulfur(Li-S)battery is considered as the most promising candidate for the energy storage systems,but its practical application is hindered by the dissolution of lithium polysulfides in the electrolyte.In this work,N-bromophthalimide(C8H4NO2Br,NBP),an aromatic molecule with carbophilic,sulfiphilic,lithiophilic,and solvophilic nature,is introduced into active graphene(AG)to fabricate the sulfur composite cathode.The carbophilic NBP is anchored readily on the AG surface viaπ−πstacking interaction.During discharging,the dissolved lithium polysulfide anion(LiS−n)is grafted into the sulfiphilic NBP spontaneously via SN2 substitution reaction to form C8H4NO2SnLi,which brings the dissolved LiS−n back to the AG surface in the composite cathode.Moreover,the lithiophilic and solvophilic nature of NBP improve the wettability of the porous composite cathode,and the electrolyte molecule is easily penetrated into the micro-mesopores of AG to facilitate the diffusion of the electrolyte.Thus,NBP,as a multi-functional compound in Li-S battery,can immobilize LiS−n and enhance the diffusion of the electrolyte.The above features of NBP endow the sulfur composite cathode with improved electrochemical performance in the cycling stability.展开更多
文摘Five corrosion inhibitors have been evaluated in high temperature naphthenic acid environment: triethyl phosphate(A), dioctylphosphoric acid(B), triphenyl phosphate(C), tetraethylenepentamine(D) and 1 aminoethyl 2 dodecylimidazoline(E). It is found that A, B and C have good inhibitory property and the corrosion inhibitory efficiency increases linearly with the hydrophilicity of inhibitor molecule; polyamine compound, being a corrosion inhibitor, reacts also with naphthenic acid to produce azole or amide compounds, which also behave as inhibitors.
基金supported by the National Natural Science Foundation of China(No.21672058 and No.21272063)
文摘Fifty-three samples of multi-substituted benzylideneanilines XArCH=NArYs （abbreviated XBAYs） were synthesized and their NMR spectra were determined. An extensional study of substituent effects on the 1H NMR chemical shifts （δH（CH=N）） and 13C NMR chemical shifts （δc（CH=N）） of the CH=N bridging group from di-substituted to multi-substituted XBAYs was made based on a total of 182 samples of XBAYs, together with the NMR data of other 129 samples of di-substituted XBAYs quoted from literatures. The results show thatthe substituent specific cross-interaction effect parameter （△（∑σ）2） plays an important role in quantifying the δc（CH=N） values of XBAYs, but it is negligible for quantifying the δH （CH=N） values; the other substituent parameters also present different influences on the δc （CH=N） and （δH （CH=N）. On the whole, the contributions of X and Y to the δc （CH=N） of XBAYs are balanced, but the δH（CH=N） values of XBAYs mainly rely on the contributions of X.
基金supported by the National Natural Science Foundation of China(51572103,51502106)the Distinguished Young Scholar of Anhui Province(1808085J14)+2 种基金the Foundation for Young Talents in College of Anhui Province(gxyqZD2017051)the Key Foundation of Educational Commission of Anhui Province(KJ2016SD53)Innovation Team of Design and Application of Advanced Energetic Materials(KJ2015TD003)~~
文摘In recent years,environmental pollution and energy crisis have become increasingly serious issues owing to the burning of fossil fuels.Among the many technologies,decomposition of water to produce hydrogen has attracted much attention because of its sustainability and non-polluting characteristic.However,highly efficient decomposition of water that is driven by visible light is still a challenge.Herein,we report the large-scale preparation of step-scheme porous graphite carbon nitride/Zn0.2Cd0.8S-diethylenetriamine(Pg-C3N4/Zn0.2Cd0.8S-DETA)composite by a facile solvothermal method.It was found by UV-vis spectroscopy that 15%Pg-C3N4/Zn0.2Cd0.8S-DETA exhibited suitable visible absorption edge and band gap for water decomposition.The hydrogen production rate of 15%Pg-C3N4/Zn0.2Cd0.8S-DETA composite was 6.69 mmol g^-1 h^-1,which was 16.73,1.61,and 1.44 times greater than those of Pg-C3N4,CdS-DETA,and Zn0.2Cd0.8S-DETA,respectively.In addition,15%Pg-C3N4/Zn0.2Cd0.8S-DETA composite displayed excellent photocatalytic stability,which was maintained for seven cycles of photocatalytic water splitting test.We believe that 15%Pg-C3N4/Zn0.2Cd0.8S-DETA composite can be a valuable guide for the development of solar hydrogen production applications in the near future.
基金supported by the National Natural Science Foundation of China (21733009, 21621063)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB17020200)~~
文摘The development of heterogeneous catalytic processes is crucial for the synthesis of chiral compounds for both academic and industrial applications.However,thus far,such achievements have remained elusive.Herein,we report the heterogeneous asymmetric hydrogenation of 2-methylquinoline over solid chiral catalysts,which were prepared by the one-pot polymerization of(1R,2R)-N-(4-vinyl-benzenesulfonyl)-1,2-diphenylethane-1,2-diamine(VDPEN)and divinylbenzene(DVB)in the presence or absence of activated carbon(C)or carbon nanotubes(CNTs),followed by Ru coordination and anion exchange.The solid chiral catalysts were fully characterized by N2 sorption analysis,elemental analysis,TEM,FT-IR spectroscopy,and 13C CP-MAS NMR.All the solid chiral catalysts could efficiently catalyze the asymmetric hydrogenation of 2-methylquinoline to afford 2-methyl-1,2,3,4-tetrahydroquinoline with 90%ee.Studies have shown that polymer/C and polymer/CNTs composites are more active than pure polymers.The polymer/CNTs composite exhibited the highest activity among all the solid chiral catalysts under identical conditions,owing to the unique morphology of CNTs.The recycling stabilities of the solid chiral catalysts were greatly improved when ionic liquids(ILs)were employed as solvents;this is mainly attributed to the decreased leaching amount of anions owing to the confinement effect of ILs on ionic compounds.
基金financially supported by the National Natural Science Foundation of China (21573112, 21935006, 21421001 and 21373118)
文摘Due to its high energy density,lithium-sulfur(Li-S)battery is considered as the most promising candidate for the energy storage systems,but its practical application is hindered by the dissolution of lithium polysulfides in the electrolyte.In this work,N-bromophthalimide(C8H4NO2Br,NBP),an aromatic molecule with carbophilic,sulfiphilic,lithiophilic,and solvophilic nature,is introduced into active graphene(AG)to fabricate the sulfur composite cathode.The carbophilic NBP is anchored readily on the AG surface viaπ−πstacking interaction.During discharging,the dissolved lithium polysulfide anion(LiS−n)is grafted into the sulfiphilic NBP spontaneously via SN2 substitution reaction to form C8H4NO2SnLi,which brings the dissolved LiS−n back to the AG surface in the composite cathode.Moreover,the lithiophilic and solvophilic nature of NBP improve the wettability of the porous composite cathode,and the electrolyte molecule is easily penetrated into the micro-mesopores of AG to facilitate the diffusion of the electrolyte.Thus,NBP,as a multi-functional compound in Li-S battery,can immobilize LiS−n and enhance the diffusion of the electrolyte.The above features of NBP endow the sulfur composite cathode with improved electrochemical performance in the cycling stability.
