Electrocatalytic conversion of carbon dioxide(CO_(2))offers an effective method of CO_(2)fixation to mitigate global warming and the energy crisis.However,for supported Ni single-atom catalysts(SACs),which are among t...Electrocatalytic conversion of carbon dioxide(CO_(2))offers an effective method of CO_(2)fixation to mitigate global warming and the energy crisis.However,for supported Ni single-atom catalysts(SACs),which are among the most promising candidates for this application,the relationship between Ni coordination structure and catalytic properties is still under strong debate.Here,we fabricated a series of Ni SACs through precise-engineering of anchor sites on nitrogen-doped carbon(NC)followed by Ni atom anchoring using atomic layer deposition.Among them,a Ni_(1)/NC SAC,with a coordination number(CN)of four but less pyridinic nitrogen(N_(pyri)),achieved over 90%faradaic efϐiciency for CO at potentials from-0.7 to-1.0 V and a mass activity of 6.5 A/mgNi at-0.78 V along with high stability,outperforming other Ni SACs with lower CN and more N_(pyri).Theoretical calculations of various three and four-coordinated Ni_(1)-NxCy structures revealed a linear correlation between the reaction Gibbs free energy for the potential-limiting step and the highest occupied molecular orbital(HOMO)position of Ni-3d orbitals,therein the four-coordinated Ni_(1)-N_(1)C_(3)with the highest HOMO position is identified as the active site for the electrocatalytic CO_(2)-to-CO process,in line with the experimental results.展开更多
On the basis of sequencing the large DNA-fragments which have been inserted intoM_(13)mp_8, we design a simple strategy to determine the complete nucleotide sequence of HBVadr NC-1 DNA with chain termination method. T...On the basis of sequencing the large DNA-fragments which have been inserted intoM_(13)mp_8, we design a simple strategy to determine the complete nucleotide sequence of HBVadr NC-1 DNA with chain termination method. The whole genome is 3195 nucleotides long.Five reading frames are observed. The gene location and organization are shown.展开更多
We investigate the bound-state equations(BSEs)in two-dimensional QCD in the N_(c)→∞limit,viewed from both the infinite momentum frame(IMF)and the finite momentum frame(FMF).The BSE of a meson in the original't H...We investigate the bound-state equations(BSEs)in two-dimensional QCD in the N_(c)→∞limit,viewed from both the infinite momentum frame(IMF)and the finite momentum frame(FMF).The BSE of a meson in the original't Hooft model,viz.,spinor QCD_(2) containing only fermionc quarks,has been extensively studied in literature.In this work,we focus on the BSEs pertaining to two types of"exotic"hadrons,a"tetraquark"which is composed of a bosonic quark and bosonic antiquark,and a"baryon"which is composed of a bosonic antiquark and a fermionic quark.Utilizing the Hamiltonian approach,we derive the corresponding BSEs for both types of"exotic"hadrons,from the perspectives of the light-front and equal-time quantization,and confirm the known results.The recently available BSEs for"tetraquark"in FMF has also been recovered with the aid of the diagrammatic approach.For the first time we also present the BSEs of a"baryon"in FMF in the extended't Hooft model.By solving various BSEs numerically,we obtain the mass spectra pertaining to"tetraquark"and"baryon"and the corresponding boundstate wave functions of the lowest-lying states.It is numerically demonstrated that,when a"tetraquark"or"baryon'is continuously boosted,the forward-moving component of the bound-state wave function approaches the corresponding light-cone wave function,while the backward-moving component fades away.展开更多
The apical sodium-dependent bile acid transporter(ASBT) is the main transporter to promote re-absorption of bile acids from the intestinal tract into the enterohepatic circulation.Inhibition of ASBT could increase the...The apical sodium-dependent bile acid transporter(ASBT) is the main transporter to promote re-absorption of bile acids from the intestinal tract into the enterohepatic circulation.Inhibition of ASBT could increase the excretion of bile acids,thus increasing bile acid synthesis and consequently cholesterol consumption.Therefore,ASBT is an attractive target for developing new cholesterol-lowering drugs.In this report,a series of 1-(2,4-bifluorophenyl)-7-dialkylamino-1,8-naphthyridine-3-carboxamides were designed as inhibitors of ASBT.Most of them demonstrated potency against ASBT transport of bile acids.In particular,compound 4a_1 was found to have the best activity,resulting in 80.1%inhibition of ASBT at10μmol/L.展开更多
文摘Electrocatalytic conversion of carbon dioxide(CO_(2))offers an effective method of CO_(2)fixation to mitigate global warming and the energy crisis.However,for supported Ni single-atom catalysts(SACs),which are among the most promising candidates for this application,the relationship between Ni coordination structure and catalytic properties is still under strong debate.Here,we fabricated a series of Ni SACs through precise-engineering of anchor sites on nitrogen-doped carbon(NC)followed by Ni atom anchoring using atomic layer deposition.Among them,a Ni_(1)/NC SAC,with a coordination number(CN)of four but less pyridinic nitrogen(N_(pyri)),achieved over 90%faradaic efϐiciency for CO at potentials from-0.7 to-1.0 V and a mass activity of 6.5 A/mgNi at-0.78 V along with high stability,outperforming other Ni SACs with lower CN and more N_(pyri).Theoretical calculations of various three and four-coordinated Ni_(1)-NxCy structures revealed a linear correlation between the reaction Gibbs free energy for the potential-limiting step and the highest occupied molecular orbital(HOMO)position of Ni-3d orbitals,therein the four-coordinated Ni_(1)-N_(1)C_(3)with the highest HOMO position is identified as the active site for the electrocatalytic CO_(2)-to-CO process,in line with the experimental results.
文摘On the basis of sequencing the large DNA-fragments which have been inserted intoM_(13)mp_8, we design a simple strategy to determine the complete nucleotide sequence of HBVadr NC-1 DNA with chain termination method. The whole genome is 3195 nucleotides long.Five reading frames are observed. The gene location and organization are shown.
基金Supported in part by the National Science Foundation of China(12475090,11925506,12435004)the Natural Science Foundation of Shandong province(ZR2022ZD26)The work of Zhewen Mo is also supported in part by the National Natural Science Foundation of China(12347145,12347105)。
文摘We investigate the bound-state equations(BSEs)in two-dimensional QCD in the N_(c)→∞limit,viewed from both the infinite momentum frame(IMF)and the finite momentum frame(FMF).The BSE of a meson in the original't Hooft model,viz.,spinor QCD_(2) containing only fermionc quarks,has been extensively studied in literature.In this work,we focus on the BSEs pertaining to two types of"exotic"hadrons,a"tetraquark"which is composed of a bosonic quark and bosonic antiquark,and a"baryon"which is composed of a bosonic antiquark and a fermionic quark.Utilizing the Hamiltonian approach,we derive the corresponding BSEs for both types of"exotic"hadrons,from the perspectives of the light-front and equal-time quantization,and confirm the known results.The recently available BSEs for"tetraquark"in FMF has also been recovered with the aid of the diagrammatic approach.For the first time we also present the BSEs of a"baryon"in FMF in the extended't Hooft model.By solving various BSEs numerically,we obtain the mass spectra pertaining to"tetraquark"and"baryon"and the corresponding boundstate wave functions of the lowest-lying states.It is numerically demonstrated that,when a"tetraquark"or"baryon'is continuously boosted,the forward-moving component of the bound-state wave function approaches the corresponding light-cone wave function,while the backward-moving component fades away.
基金supported by the National Natural Science Foundation of China(Nos.81473098 and 81473099)Hebei Provincial Key Research Project of Medical Science(Nos.ZD20140027 and 20150588)
文摘The apical sodium-dependent bile acid transporter(ASBT) is the main transporter to promote re-absorption of bile acids from the intestinal tract into the enterohepatic circulation.Inhibition of ASBT could increase the excretion of bile acids,thus increasing bile acid synthesis and consequently cholesterol consumption.Therefore,ASBT is an attractive target for developing new cholesterol-lowering drugs.In this report,a series of 1-(2,4-bifluorophenyl)-7-dialkylamino-1,8-naphthyridine-3-carboxamides were designed as inhibitors of ASBT.Most of them demonstrated potency against ASBT transport of bile acids.In particular,compound 4a_1 was found to have the best activity,resulting in 80.1%inhibition of ASBT at10μmol/L.
