Yolk-shell SiO2 particles(YP)with center-radial meso-channels were fabricated through a simple and effective method.Al-containing YP-supported NiMo catalysts with different Al amounts(NiMo/AYP-x,x=Si/Al molar proporti...Yolk-shell SiO2 particles(YP)with center-radial meso-channels were fabricated through a simple and effective method.Al-containing YP-supported NiMo catalysts with different Al amounts(NiMo/AYP-x,x=Si/Al molar proportion)were prepared and dibenzothiophene(DBT)and 4,6-dimethyl-dibenzothiophene(4,6-DMDBT)were employed as the probes to evaluate the hydrodesulfurization(HDS)catalytic performance.The as-prepared AYP-x carriers and corresponding catalysts were characterized by some advanced characterizations to obtain deeper correlations between physicochemical properties and the HDS performance.The average pore sizes of series AYP-x supports are above 6.0 nm,which favors the mass transfer of organic sulfides.The cavity between the yolk and the shell is beneficial for the enrichment of S-containing compounds and the accessibility between reactants and active metals.Aluminum embedded into the silica framework could facilitate the formation of Lewis(L)and Brønsted(B)acid sites and adjust the metal-support interaction(MSI).Among all the as-synthesized catalysts,NiMo/AYP-20 catalyst shows the highest HDS activities.The improved HDS activity of NiMo/AYP-20 catalyst is attributed to the perfect combination of excellent structural properties of the yolk-shell mesoporous silica,enhanced acidity,moderate MSI,and good accessibility/dispersion of active components.展开更多
All-solid-state lithium metal batteries(ASSLMBs)are considered as one of the ultimate goals for the development of energy storage systems due to their high energy density and high safety.However,the mismatching of int...All-solid-state lithium metal batteries(ASSLMBs)are considered as one of the ultimate goals for the development of energy storage systems due to their high energy density and high safety.However,the mismatching of interface transport kinetics as well as interfacial instability induces the growth of lithium dendrite and thus,leads to severe degradation of battery electrochemical performances.Herein,an integrated interface configuration(IIC)consisting of in-situ generated Li I interphase and Li-Ag alloy anode is proposed through in-situ interface chemistry.The IIC is capable of not only regulating charge transport kinetics but also synchronously stabilizing the lithium/electrolyte interface,thereby achieving uniform lithium platting.Therefore,Li||Li symmetric cells with IIC achieve a critical current density of up to 1.6 mA cm^(-2)and achieve stable cycling over 1600 hours at a high current density of 0.5 mA cm^(-2).Moreover,a high discharge capacity of 140.1 mA h g-1at 0.1 C is also obtained for the Li(Ni_(0.6)Co_(0.2)Mn_(0.2))O_(2)(NCM622)full battery with a capacity retention of 65.6%after 300 cycles.This work provides an effective method to synergistically regulate the interface transport kinetics and inhibit lithium dendrite growth for high-performance ASSLMBs.展开更多
A novel composite material(TD)composed of TS-1 microcrystalline and dendritic mesoporous silica nanospheres(DMSNs)was successfully prepared.The TD composite material had open pore structure and large specific surface ...A novel composite material(TD)composed of TS-1 microcrystalline and dendritic mesoporous silica nanospheres(DMSNs)was successfully prepared.The TD composite material had open pore structure and large specific surface area,which was conducive to the mass transfer of reactants and products.The Ti element in TS-1 could be used as an electron assistant,and the spillover d-electrons were conducive to the improvement of the sulfidation and dispersion of MoS_(2),thereby forming more type II MoS_(2) active phases.The incorporation of Ti could bring more Brønsted(B)and Lewis(L)acid,which was conducive to the hydrogenation pathway(HYD)selectivity(41.2%)of dibenzothiophene(DBT)hydrodesulfurization(HDS)and isomerization(ISO)route selectivity(21.9%)of 4,6-dimethyldibenzothiophene(4,6-DMDBT)HDS,thus improve the HDS activity of DBT and 4,6-DMDBT.NiMo/TD-70(Aging temperature=70℃)had the best HDS activities of DBT(99.0%)and 4,6-DMDBT(93.7%)due to its large open pore structure,good acidity,suitable metal-support interaction(MSI)and perfect dispersion of the metallic active sites.展开更多
Four new species of Orchidaceae from China,Heminium lijiangense,Peristylus fasciculatus,Platanthera milinensis,and Ponerorchis gongshanensis,together with a new country record,Peristylus tenuicallus,are described and ...Four new species of Orchidaceae from China,Heminium lijiangense,Peristylus fasciculatus,Platanthera milinensis,and Ponerorchis gongshanensis,together with a new country record,Peristylus tenuicallus,are described and illustrated based on morphological and/or phylogenetic analyses.Heminium lijiangense is closely related to H.elisabethae but differs from it by having the dorsal sepal ovate-orbicular and lip midlobe distinctly shorter than lateral lobes.P.fasciculatus is close to Peristylus tradescantifolius but is distinguished from it by having several fascicled and straight,root-like tubers(vs.one or two oblongoid tubers),old stems usually persistent,middle lobe of lip narrowly ligulate-lanceolate and half as long as the lateral lobes(vs.middle lobe deltoid,about a third as long as the lateral lobes or less),a raised callus at the base of each lateral lobe(vs.callus absent),spur gradually attenuate toward the apex(vs.spur clavate).Platanthera milinensis is similar to P.stenochila by sharing small green flowers and lip without a spur,but differs in having a creeping rhizome,a corymbose inflorescence,and a broadly ovate and slightly 3-lobed lip.Ponerochis gongshanensis is similar to P.faberi in its small flowers,but differs in having a linear leaf c.3 mm wide(vs.leaf 5-13 mm wide),in the lip having collar-like raised margins on the sides of the spur entrance,and a mid-lobe which is notched at the apex but not divided into two divergent lobules that are nearly as large as the lateral lobes,as in P.faberi.All the proposed species obtained high support in phylogenetic analysis as new species.The recently described genus Apetalanthe is reduced to synonymy of Ponerorchis and a new combination is made.展开更多
Hierarchically porous Beta/SBA-16(BS)composite materials,combining the characteristics of the acidity from the Beta zeolite and the three-dimensional structure from SBA-16,were synthesized successfully through a two-s...Hierarchically porous Beta/SBA-16(BS)composite materials,combining the characteristics of the acidity from the Beta zeolite and the three-dimensional structure from SBA-16,were synthesized successfully through a two-step in-situ assembly hydrothermal crystallization method.A series of Ni Mo catalysts supported on BS with different silica-alumina ratios were prepared.The supports and the corresponding catalysts were characterized by XRD,N_(2) physisorption,^(27)Al MAS NMR,TEM,pyridine-FTIR,Raman,XPS and HRTEM.The activities of series catalysts were evaluated by the hydrodesulfurization(HDS)performances of dibenzothiophene(DBT)and 4,6-dimethyldibenzothiophene(4,6-DMDBT).It was found that the Beta crystallites were embedded into SBA-16 through silanols accompanied by dealumination on the T3-T9 sites of Beta crystallites.Ni Mo/BS-3 with a silica-alumina ratio of 100 exhibited the highest DBT and 4,6-DMDBT HDS activities at the WHSV value of 10 h^(-1),with the conversions of 95.9%and 86.9%respectively,due to the synergistic effects of the suitable specific surface areas,the relatively large pore size,appropriate acidity,the relatively high sulfidation degree,moderate dispersity and good stacking degree of Mo S;active phases.展开更多
基金The authors acknowledge the financial supports from the National Science Foundation of China(U1908204,91845201,and 22002093)the funds that Central Government Guides Local Science and Technology Development(2022JH6/100100052)Scientific Research Project of Education Department of Liaoning Province(LQN202006).
文摘Yolk-shell SiO2 particles(YP)with center-radial meso-channels were fabricated through a simple and effective method.Al-containing YP-supported NiMo catalysts with different Al amounts(NiMo/AYP-x,x=Si/Al molar proportion)were prepared and dibenzothiophene(DBT)and 4,6-dimethyl-dibenzothiophene(4,6-DMDBT)were employed as the probes to evaluate the hydrodesulfurization(HDS)catalytic performance.The as-prepared AYP-x carriers and corresponding catalysts were characterized by some advanced characterizations to obtain deeper correlations between physicochemical properties and the HDS performance.The average pore sizes of series AYP-x supports are above 6.0 nm,which favors the mass transfer of organic sulfides.The cavity between the yolk and the shell is beneficial for the enrichment of S-containing compounds and the accessibility between reactants and active metals.Aluminum embedded into the silica framework could facilitate the formation of Lewis(L)and Brønsted(B)acid sites and adjust the metal-support interaction(MSI).Among all the as-synthesized catalysts,NiMo/AYP-20 catalyst shows the highest HDS activities.The improved HDS activity of NiMo/AYP-20 catalyst is attributed to the perfect combination of excellent structural properties of the yolk-shell mesoporous silica,enhanced acidity,moderate MSI,and good accessibility/dispersion of active components.
基金supported by the Beijing Natural Science Foundation(L223009)the National Natural Science Foundation of China(22075029)+1 种基金the National Key Research and Development Program of China(2021YFB2500300)the Key Research and Development(R&D)Projects of Shanxi Province(2021020660301013)。
文摘All-solid-state lithium metal batteries(ASSLMBs)are considered as one of the ultimate goals for the development of energy storage systems due to their high energy density and high safety.However,the mismatching of interface transport kinetics as well as interfacial instability induces the growth of lithium dendrite and thus,leads to severe degradation of battery electrochemical performances.Herein,an integrated interface configuration(IIC)consisting of in-situ generated Li I interphase and Li-Ag alloy anode is proposed through in-situ interface chemistry.The IIC is capable of not only regulating charge transport kinetics but also synchronously stabilizing the lithium/electrolyte interface,thereby achieving uniform lithium platting.Therefore,Li||Li symmetric cells with IIC achieve a critical current density of up to 1.6 mA cm^(-2)and achieve stable cycling over 1600 hours at a high current density of 0.5 mA cm^(-2).Moreover,a high discharge capacity of 140.1 mA h g-1at 0.1 C is also obtained for the Li(Ni_(0.6)Co_(0.2)Mn_(0.2))O_(2)(NCM622)full battery with a capacity retention of 65.6%after 300 cycles.This work provides an effective method to synergistically regulate the interface transport kinetics and inhibit lithium dendrite growth for high-performance ASSLMBs.
基金This research was supported by the Science Foundation of China University of Petroleum-Beijing(No.2462023QNXZ002)the National Key R&D Program of China(2021YFA1501201)+2 种基金the National Natural Science Foundation of China(No.22278174)Independent research project of State Key Laboratory of heavy oil(2021–01)Shandong Excellent Young Scientists Fund Program(Overseas,2022HWYQ-082).
文摘A novel composite material(TD)composed of TS-1 microcrystalline and dendritic mesoporous silica nanospheres(DMSNs)was successfully prepared.The TD composite material had open pore structure and large specific surface area,which was conducive to the mass transfer of reactants and products.The Ti element in TS-1 could be used as an electron assistant,and the spillover d-electrons were conducive to the improvement of the sulfidation and dispersion of MoS_(2),thereby forming more type II MoS_(2) active phases.The incorporation of Ti could bring more Brønsted(B)and Lewis(L)acid,which was conducive to the hydrogenation pathway(HYD)selectivity(41.2%)of dibenzothiophene(DBT)hydrodesulfurization(HDS)and isomerization(ISO)route selectivity(21.9%)of 4,6-dimethyldibenzothiophene(4,6-DMDBT)HDS,thus improve the HDS activity of DBT and 4,6-DMDBT.NiMo/TD-70(Aging temperature=70℃)had the best HDS activities of DBT(99.0%)and 4,6-DMDBT(93.7%)due to its large open pore structure,good acidity,suitable metal-support interaction(MSI)and perfect dispersion of the metallic active sites.
基金Project of Orchid Biodiversity Survey of ChinaNational Forestry and Grassland Administration+2 种基金the National Natural Science Foundation of China(No.31670194)the Large-scale Scientific Facilities of theChinese Academy of Sciences(Grant No.2017-LSFGBOWS-02)the National Wild Plant Germplasm Resource Center。
文摘Four new species of Orchidaceae from China,Heminium lijiangense,Peristylus fasciculatus,Platanthera milinensis,and Ponerorchis gongshanensis,together with a new country record,Peristylus tenuicallus,are described and illustrated based on morphological and/or phylogenetic analyses.Heminium lijiangense is closely related to H.elisabethae but differs from it by having the dorsal sepal ovate-orbicular and lip midlobe distinctly shorter than lateral lobes.P.fasciculatus is close to Peristylus tradescantifolius but is distinguished from it by having several fascicled and straight,root-like tubers(vs.one or two oblongoid tubers),old stems usually persistent,middle lobe of lip narrowly ligulate-lanceolate and half as long as the lateral lobes(vs.middle lobe deltoid,about a third as long as the lateral lobes or less),a raised callus at the base of each lateral lobe(vs.callus absent),spur gradually attenuate toward the apex(vs.spur clavate).Platanthera milinensis is similar to P.stenochila by sharing small green flowers and lip without a spur,but differs in having a creeping rhizome,a corymbose inflorescence,and a broadly ovate and slightly 3-lobed lip.Ponerochis gongshanensis is similar to P.faberi in its small flowers,but differs in having a linear leaf c.3 mm wide(vs.leaf 5-13 mm wide),in the lip having collar-like raised margins on the sides of the spur entrance,and a mid-lobe which is notched at the apex but not divided into two divergent lobules that are nearly as large as the lateral lobes,as in P.faberi.All the proposed species obtained high support in phylogenetic analysis as new species.The recently described genus Apetalanthe is reduced to synonymy of Ponerorchis and a new combination is made.
基金supported by the National Natural Science Foundation of China(No.21878330,21676298)the National Science and Technology Major Project(No.2019YFC1907700)+1 种基金the CNPC Key Research Project(2016E-0707)the King Abdullah University of Science and Technology(KAUST)。
文摘Hierarchically porous Beta/SBA-16(BS)composite materials,combining the characteristics of the acidity from the Beta zeolite and the three-dimensional structure from SBA-16,were synthesized successfully through a two-step in-situ assembly hydrothermal crystallization method.A series of Ni Mo catalysts supported on BS with different silica-alumina ratios were prepared.The supports and the corresponding catalysts were characterized by XRD,N_(2) physisorption,^(27)Al MAS NMR,TEM,pyridine-FTIR,Raman,XPS and HRTEM.The activities of series catalysts were evaluated by the hydrodesulfurization(HDS)performances of dibenzothiophene(DBT)and 4,6-dimethyldibenzothiophene(4,6-DMDBT).It was found that the Beta crystallites were embedded into SBA-16 through silanols accompanied by dealumination on the T3-T9 sites of Beta crystallites.Ni Mo/BS-3 with a silica-alumina ratio of 100 exhibited the highest DBT and 4,6-DMDBT HDS activities at the WHSV value of 10 h^(-1),with the conversions of 95.9%and 86.9%respectively,due to the synergistic effects of the suitable specific surface areas,the relatively large pore size,appropriate acidity,the relatively high sulfidation degree,moderate dispersity and good stacking degree of Mo S;active phases.