The highest occupied molecular orbital(HOMO) energies of fullerenes are found by quantitative first-principles calculations to be raised by negative charging, and the rising rate rank of the fullerenes is C60 >C7...The highest occupied molecular orbital(HOMO) energies of fullerenes are found by quantitative first-principles calculations to be raised by negative charging, and the rising rate rank of the fullerenes is C60 >C70 >C80 >C90>C100 >C180. Then we compare fullerenes with carbon nanotubes(CNTs) and graphene sheets(GSs) and find that the increase of the HOMO energy of a fullerene is much faster than that of CNTs and graphene sheets with the same number of C atoms. The rising rate rank is fullerene>CNT>GS, which holds no matter what the number of C atoms is or which structure the fullerene isomer is. This work paves a new path for developing all-carbon devices with low-dimensional carbon nanomaterials as different functional elements.展开更多
Jarzynski' identity (JI) method was suggested a promising tool for reconstructing free energy landscape of biomolecular interactions in numerical simulations and ex- periments. However, JI method has not yet been w...Jarzynski' identity (JI) method was suggested a promising tool for reconstructing free energy landscape of biomolecular interactions in numerical simulations and ex- periments. However, JI method has not yet been well tested in complex systems such as ligand-receptor molecular pairs. In this paper, we applied a huge number of steered molec- ular dynamics (SMD) simulations to dissociate the protease of human immunodeficiency type I virus (HIV-1 protease) and its inhibitors. We showed that because of intrinsic com- plexity of the ligand-receptor system, the energy barrier pre- dicted by JI method at high pulling rates is much higher than experimental results. However, with a slower pulling rate and fewer switch times of simulations, the predictions of JI method can approach to the experiments. These results sug- gested that the JI method is more appropriate for reconstruct- ing free energy landscape using the data taken from experi- ments, since the pulling rates used in experiments are often much slower than those in SMD simulations. Furthermore, we showed that a higher loading stiffness can produce higher precision of calculation of energy landscape because it yields a lower mean value and narrower bandwidth of work distri- bution in SMD simulations.展开更多
The microscopic moleeular theory for electron transfer in a model solvent ishahr developed. The nonlinear response of the solvent molecules is be computedquanitatively in a new way. Adopting computer simulation daa an...The microscopic moleeular theory for electron transfer in a model solvent ishahr developed. The nonlinear response of the solvent molecules is be computedquanitatively in a new way. Adopting computer simulation daa and choosingappropriate reaction coordinae, a reasonable free energy dinram is constructed and thercorganhaion energy for the product state is calculated.展开更多
The comparison between single-point energy scanning (SPES) and geometry optimization (OPT) in determining the equilibrium geometries of c^3∑g^+ and B^1-Пu states of dimer 7Li2 is made at numerous basis sets by ...The comparison between single-point energy scanning (SPES) and geometry optimization (OPT) in determining the equilibrium geometries of c^3∑g^+ and B^1-Пu states of dimer 7Li2 is made at numerous basis sets by using a symmetryadapted-cluster configuration-interaztion (SAC-CI) method in the Gaussian 03 program package. In this paper the difference of the equilibrium geometries obtained by SPES and by OPT is reported. The results obtained by SPES are found to be more reasonable than those obtained by OPT in full active space at the present SAC-CI level of theory. And the conclusion is attained that the cc-PVTZ is a most suitable basis set for these states. The calculated dissociation energies and equilibrium geometries are 0.8818 eV and 0.3090 nm for c^3∑g^+ state, and 0.3668 eV and 0.2932 nm for B^1-Пu state respectively. The potential energy curves are calculated over a wide internuclear distance range from about 2.5α0 to 37α0 and have a least-squares fit into the Murrell-Sorbie function. According to the calculated analytic potential energy functions, the harmonic frequencies (We) and other spectroscopic data (ωeXe, Be and αe) are calculated. Comparison of the theoretical determinations at present work with the experiments and other theories clearly shows that the present work is the most complete effort and thus represents an improvement over previous theoretical results.展开更多
The interactions of complexes of XeOF_(2) and XeO_(3) with a series of different hybridization N-containing donors are studied by means of DFT and MP_(2) calculations.The aerogen bonding interaction energies range fro...The interactions of complexes of XeOF_(2) and XeO_(3) with a series of different hybridization N-containing donors are studied by means of DFT and MP_(2) calculations.The aerogen bonding interaction energies range from 6.5 kcal/mol to19.9 kcal/mol between XeO_(3) or XeOF_(2) and typical N-containing donors.The sequence of interaction for N-containing hy-bridization is sp^(3)>sp^(2)>sp,and XeO_(3)is higher than XeOF_(2).For some donors of sp^(2)and sp^(3) hybridization,the steric effect plays a minor role in the interaction with the evidence of reduced density gradient plots.The dominant stable part is the electrostatic interaction.In complex of XeO_(3),the weight of polarization is larger than dispersion,while the situation is opposite for XeOF_(2)complexes.Except for the sum of the maximum value of molecular electrostatic potential on Xe atom and minimum value of molecular electrostatic potential on N atom,the other five interaction parameters including the potential energy density at bond critical point,the equilibrium distances,interaction energies with the basis set superposition error correction,localized molecular orbital energy decomposition analysis interaction energies,and the electron charge density,show great linear correlation coefficients with each other.展开更多
Under the new energy resource structure,electrocatalysts are key materials for the development of proton membrane fuel cells,electrolysis of aquatic hydrogen devices,and carbon dioxide reduction equipment,to address e...Under the new energy resource structure,electrocatalysts are key materials for the development of proton membrane fuel cells,electrolysis of aquatic hydrogen devices,and carbon dioxide reduction equipment,to address energy shortages and even environmental pollution issues.Although controlling the morphology or doping with heteroatoms for catalyst active centers have accelerated the reaction rate,it is difficult to solve the problems of multiple by-products,and poor stability of catalytic sites.From this,it will be seen that single regulation of metal active centers is difficult to comprehensively solve application problems.Orderly assembly and coordination of catalyst multi-hierarchy structures at the mesoscale above the nanometer level probably be more reasonable strategies,and numerous studies in thermal catalysis have supported this viewpoint.This article reviews the multi-hierarchy design of electrocatalyst active centers,high-energy supports,and peripheral structures in recent years,providing unconventional inspiration about electrocatalyst creation,which perhaps serves as a simple tutorial of electrocatalysis exploration for abecedarian.展开更多
Carbon monosulfide molecular ion (CS+), which plays an important role in various research fields, has long been attracting much interest. Because of the unstable and transient nature of CS+, its electronic states ...Carbon monosulfide molecular ion (CS+), which plays an important role in various research fields, has long been attracting much interest. Because of the unstable and transient nature of CS+, its electronic states have not been well investigated. In this paper, the electronic states of CS+ are studied by employing the internally contracted multireference configuration interaction method, and taking into account relativistic effects (scalar plus spin–orbit coupling). The spin–orbit coupling effects are considered via the state-interacting method with the full Breit–Pauli Hamiltonian. The potential energy curves of 18 Λ–S states correlated with the two lowest dissociation limits of CS+ molecular ion are calculated, and those of 10 lowest Ω states generated from the 6 lowest Λ–S states are also worked out. The spectroscopic constants of the bound states are evaluated, and they are in good agreement with available experimental results and theoretical values. With the aid of analysis of Λ–S composition of Ω states at different bond lengths, the avoided crossing phenomena in the electronic states of CS+ are illuminated. Finally, the single ionization spectra of CS (X1Σ+) populating the CS+(X2Σ1/2+, A2Π3/2, A2Π1/2, and B2Σ1/2+) states are simulated. The vertical ionization potentials for X2Σ1/2+, A2Π3/2, A2Π1/2, and B2Σ1/2+ states are calculated to be 11.257, 12.787, 12.827, and 15.860 eV, respectively, which are accurate compared with previous experimental results, within an error margin of 0.08 eV^0.2 eV.展开更多
Molecular simulation was performed to study the interaction between CaCO3 crystal and several oligomer inhibitors, by using the equilibrium morphology method to calculate the growth morphology of CaCO3 without inhibit...Molecular simulation was performed to study the interaction between CaCO3 crystal and several oligomer inhibitors, by using the equilibrium morphology method to calculate the growth morphology of CaCO3 without inhibitors. The calculated morphology agreed well with SEM photographs. Then, a double-layer model was built to investigate the interaction between calcite crystal and oligomer inhibitors containing maleic anhydride (MA) and acrylic acid (AA). Interaction energy per gram of an oligomer inhibitor was introduced as a scale of inhibition efficiency of different monomers. The results indicated that, for calcite scale inhibition, acrylamide (AM) and vinyl phosphonic acid (VPA) were the most efficient monomers, while allylsulfonic acid (AS) was the poorest. Increasing proportion of AM in dimer inhibitor molecule would improve the inhibition efficiency of MA, though, for a trimer, such as MA-AA-AM, certain sequence of monomers in the inhibitor molecule was necessary besides higher proportion of AM.展开更多
A series of core-expanded naphthalene diimides(NDI-DTYM) and thiophene-based derivatives(1a-c)were designed and synthesized to investigate the relationship between molecular structures and the highest occupied mol...A series of core-expanded naphthalene diimides(NDI-DTYM) and thiophene-based derivatives(1a-c)were designed and synthesized to investigate the relationship between molecular structures and the highest occupied molecular orbital(HOMO) energy levels but has little impact on the lowest unoccupied molecular orbital(LUMO) energy levels.The results demonstrated that increasing the number of thiophene units can gradually elevate the HOMO energy levels but had little impact on the LUMO energy levels.The n-channel organic field-effect transistors(OFETs) based on 1b and 1c have demonstrated that these almost unchanged LUMO energy levels are proper to transport electrons.展开更多
In scanning tunneling microscopy-induced luminescence(STML),the photon count is measured to reflect single-molecule properties,e.g.,the first molecular excited state.The energy of the first excited state is typically ...In scanning tunneling microscopy-induced luminescence(STML),the photon count is measured to reflect single-molecule properties,e.g.,the first molecular excited state.The energy of the first excited state is typically shown by a rise of the photon count as a function of the bias voltage between the tip and the substrate.It remains a challenge to determine the precise rise position of the current due to possible experimental noise.In this work,we propose an alternating current version of STML to resolve the fine structures in the photon count measurement.The measured photon count and the current at the long-time limit show a sinusoidal oscillation.The zero-frequency component of the current shows knee points at the precise voltage as the fraction of the detuning between the molecular gap and the DC component of the bias voltage.We propose to measure the energy level with discontinuity of the first derivative of such a zero-frequency component.The current method will extend the application of STML in terms of measuring molecular properties.展开更多
A large of energy consumption is required for indoor and outdoor personal heating to ameliorate the comfortable and healthy conditions.Main personal thermal management strategy is to reflect mid-infrared human body ra...A large of energy consumption is required for indoor and outdoor personal heating to ameliorate the comfortable and healthy conditions.Main personal thermal management strategy is to reflect mid-infrared human body radiation for human surface temperature(THS)regulation.We demonstrate a visible Janus light absorbent/reflective air-layer fabric(Janus A/R fabric)that can passively reflect radiative heating meanwhile can actively capture the solar energy.A series of azobenzene derivatives functionalized with alkyl tails are reported to co-harvest the solar and phase-change energy.The THS covered by Janus A/R fabric can be heated up to~3.7°C higher than that covered by air-layer fabric in cold environment(5°C).Besides,integrating the thermo-and photo-chromic properties is capable of monitoring comfort THS and residue energy storage enthalpy,respectively.According to the colour monitors,intermittent irradiation approach is proposed to prolong comfortable-THS holding time for managing energy efficiently.展开更多
Based on the generalized gradient approximation (GGA), Perdew-Wang-91 (PW91) combined with a periodic slab model has been applied to study the catalytic activity of chlorine evolution on TinRumO2 (1 1 0) surface...Based on the generalized gradient approximation (GGA), Perdew-Wang-91 (PW91) combined with a periodic slab model has been applied to study the catalytic activity of chlorine evolution on TinRumO2 (1 1 0) surface. Metal oxide model TinRumO2 has been established with pure TiO2 and Ru02 on the basis set of Double Numerical plus polarization (DNP), in which the proportion of n:m was 3:1, 1 :l, or 1:3. Analysis on the reaction activity in the electrochemical reaction and the electrochemical desorption reaction was based on Frontier molecular orbital theory. The results show that the TinRumO2 with a ratio of Ti:Ru at 3:1 is best facilitates the electrochemical reaction and electrochemical desorption reaction to produce M-Clads intermediate and precipitate C12. In addition, the adsorption energy of Cl on the surface of Ti3RU102 possesses the minimum value of 2.514 eV, and thus electrochemical desorption reaction could occur most easily.展开更多
The energies, geometries and harmonic vibrational frequencies of 1 : 1 5-hydroxytryptamine-water (5-HT-H20) complexes are studied at the MP2/6-311 + + G(d,p) level. Natural bond orbital (NBO), quantum theory ...The energies, geometries and harmonic vibrational frequencies of 1 : 1 5-hydroxytryptamine-water (5-HT-H20) complexes are studied at the MP2/6-311 + + G(d,p) level. Natural bond orbital (NBO), quantum theory of atoms in molecules (QTAIM) analyses and the localized molecular orbital energy decomposition analysis (LMO-EDA) were performed to explore the nature of the hydrogen-bonding interactions in these complexes. Various types of hydro- gen bonds (H-bonds) are formed in these 5-HT-H20 complexes. The intermolecular C4H55HT'"Ow H-bond in HTW3 is strengthened due to the cooperativity, whereas no such cooperativity is found in the other 5-HT-H20 complexes. H-bond in which nitrogen atom of amino in 5-HT acted as proton donors was stronger than other H-bonds. Our researches show that the hydrogen bonding interaction plays a vital role on the relative stabilities of 5-HT-H20 complexes.展开更多
Designing molecular logic gates to operate programmably for molecular diagnostics in molecular computing still remains challenging.Here,we designed a novel linear DNA logic gates for microRNA analysis based on strand ...Designing molecular logic gates to operate programmably for molecular diagnostics in molecular computing still remains challenging.Here,we designed a novel linear DNA logic gates for microRNA analysis based on strand displacement and fluorescence resonance energy transfer(FRET).Two labeled strands closed each other produce to FRET through hybridization with a complementary strand to form a basic work unit of logic gate.Two indicators of heart failure(microRNA-195 and microRNA-21) were selected as the logic inputs and the fluorescence mode was used as the logic output.We have demonstrated that the molecular logic gate mechanism worked well with the construction of YES and AND gates.展开更多
Hand,foot,and mouth disease(HFMD),primarily instigated by Coxsackievirus A16(CVA16),poses a serious health concern,necessitating effective therapeutic interventions.The RNA-dependent RNA polymerase(RdRp)of CVA16 emerg...Hand,foot,and mouth disease(HFMD),primarily instigated by Coxsackievirus A16(CVA16),poses a serious health concern,necessitating effective therapeutic interventions.The RNA-dependent RNA polymerase(RdRp)of CVA16 emerges as a promising drug target for HFMD treatment.This study presents an in-silico pipeline for the identification of potential RdRp inhibitors against CVA16.A library of 91 natural compounds derived from Bacopa monnieri(brahmi)was virtually screened against the CVA16 RdRp.Here,Bacobitacin D emerged as a promising hit molecule,forming 8 hydrogen bonds including key catalytic site residues(Asp^(238)and Asp^(329))within the RdRp active site.Further,molecular dynamics(MD)simulations and MM/GBSA binding free energy calculations was applied on the top three hits that were selected based on exhaustive docking scores(≤-9.55 kcal/mol).Bacobitacin D exhibited sustainable stability,as evidenced by minimal deviation(RMSD=0.75±0.02 nm)during a 100 ns MD simulation.Importantly,Bacopaside IV exhibited the lowestΔGTOTAL binding free energy(-23.70 kcal/mol),while Bacobitacin D displayed a comparableΔGTOTAL of19.14 kcal/mol.Structural interpretation of the most populated cluster derived from MD simulations showed direct interactions of Bacobitacin D with pivotal catalytic residues,including Asp^(238)and Ser^(289).This comprehensive study confirmed Bacobitacin D as a potent inhibitor of CVA16 RdRp,offering a potential avenue for therapeutic intervention against HFMD.Experimental validation is required to confirm the inhibitory action of Bacobitacin D against HFMD.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11374174,51390471,51527803,and 51701143the National Basic Research Program of China under Grant No 2015CB654902+4 种基金the National Key Research and Development Program under Grant No 2016YFB0700402the Foundation for the Author of National Excellent Doctoral Dissertation under Grant No 201141the National Program for Thousand Young Talents of China,the Tianjin Municipal Education Commissionthe Tianjin Municipal Science and Technology Commissionthe Fundamental Research Fund of Tianjin University of Technology
文摘The highest occupied molecular orbital(HOMO) energies of fullerenes are found by quantitative first-principles calculations to be raised by negative charging, and the rising rate rank of the fullerenes is C60 >C70 >C80 >C90>C100 >C180. Then we compare fullerenes with carbon nanotubes(CNTs) and graphene sheets(GSs) and find that the increase of the HOMO energy of a fullerene is much faster than that of CNTs and graphene sheets with the same number of C atoms. The rising rate rank is fullerene>CNT>GS, which holds no matter what the number of C atoms is or which structure the fullerene isomer is. This work paves a new path for developing all-carbon devices with low-dimensional carbon nanomaterials as different functional elements.
基金supported by the National Science Foundation of China (10732050,10872115 and 11025208)Excellent Young Scholars Research Fund of Beijing Institute of Technology
文摘Jarzynski' identity (JI) method was suggested a promising tool for reconstructing free energy landscape of biomolecular interactions in numerical simulations and ex- periments. However, JI method has not yet been well tested in complex systems such as ligand-receptor molecular pairs. In this paper, we applied a huge number of steered molec- ular dynamics (SMD) simulations to dissociate the protease of human immunodeficiency type I virus (HIV-1 protease) and its inhibitors. We showed that because of intrinsic com- plexity of the ligand-receptor system, the energy barrier pre- dicted by JI method at high pulling rates is much higher than experimental results. However, with a slower pulling rate and fewer switch times of simulations, the predictions of JI method can approach to the experiments. These results sug- gested that the JI method is more appropriate for reconstruct- ing free energy landscape using the data taken from experi- ments, since the pulling rates used in experiments are often much slower than those in SMD simulations. Furthermore, we showed that a higher loading stiffness can produce higher precision of calculation of energy landscape because it yields a lower mean value and narrower bandwidth of work distri- bution in SMD simulations.
文摘The microscopic moleeular theory for electron transfer in a model solvent ishahr developed. The nonlinear response of the solvent molecules is be computedquanitatively in a new way. Adopting computer simulation daa and choosingappropriate reaction coordinae, a reasonable free energy dinram is constructed and thercorganhaion energy for the product state is calculated.
基金Project supported by the National Natural Science Foundation of China (Grant No 10574039), the Henan Innovation for University Prominent Research Talents (Grant No 2006KYCX002) and the National Natural Science Foundation of Education Bureau of Henan Province, China (Grant No 2007140015). We heartily thank Professor Zhu Zheng-Hem of Sichuan University for his helpful discussion about the reasonable dissociation stages of these calculations limits during the planning
文摘The comparison between single-point energy scanning (SPES) and geometry optimization (OPT) in determining the equilibrium geometries of c^3∑g^+ and B^1-Пu states of dimer 7Li2 is made at numerous basis sets by using a symmetryadapted-cluster configuration-interaztion (SAC-CI) method in the Gaussian 03 program package. In this paper the difference of the equilibrium geometries obtained by SPES and by OPT is reported. The results obtained by SPES are found to be more reasonable than those obtained by OPT in full active space at the present SAC-CI level of theory. And the conclusion is attained that the cc-PVTZ is a most suitable basis set for these states. The calculated dissociation energies and equilibrium geometries are 0.8818 eV and 0.3090 nm for c^3∑g^+ state, and 0.3668 eV and 0.2932 nm for B^1-Пu state respectively. The potential energy curves are calculated over a wide internuclear distance range from about 2.5α0 to 37α0 and have a least-squares fit into the Murrell-Sorbie function. According to the calculated analytic potential energy functions, the harmonic frequencies (We) and other spectroscopic data (ωeXe, Be and αe) are calculated. Comparison of the theoretical determinations at present work with the experiments and other theories clearly shows that the present work is the most complete effort and thus represents an improvement over previous theoretical results.
基金financially supported by the China Postdoctoral Science Foundation(No.2020M682154)。
文摘The interactions of complexes of XeOF_(2) and XeO_(3) with a series of different hybridization N-containing donors are studied by means of DFT and MP_(2) calculations.The aerogen bonding interaction energies range from 6.5 kcal/mol to19.9 kcal/mol between XeO_(3) or XeOF_(2) and typical N-containing donors.The sequence of interaction for N-containing hy-bridization is sp^(3)>sp^(2)>sp,and XeO_(3)is higher than XeOF_(2).For some donors of sp^(2)and sp^(3) hybridization,the steric effect plays a minor role in the interaction with the evidence of reduced density gradient plots.The dominant stable part is the electrostatic interaction.In complex of XeO_(3),the weight of polarization is larger than dispersion,while the situation is opposite for XeOF_(2)complexes.Except for the sum of the maximum value of molecular electrostatic potential on Xe atom and minimum value of molecular electrostatic potential on N atom,the other five interaction parameters including the potential energy density at bond critical point,the equilibrium distances,interaction energies with the basis set superposition error correction,localized molecular orbital energy decomposition analysis interaction energies,and the electron charge density,show great linear correlation coefficients with each other.
基金supported by the National Natural Science Foundation of China(91963206,21932004,21872067,22172072)the Ministry of Science and Technology of China(2021YFA1500301)。
文摘Under the new energy resource structure,electrocatalysts are key materials for the development of proton membrane fuel cells,electrolysis of aquatic hydrogen devices,and carbon dioxide reduction equipment,to address energy shortages and even environmental pollution issues.Although controlling the morphology or doping with heteroatoms for catalyst active centers have accelerated the reaction rate,it is difficult to solve the problems of multiple by-products,and poor stability of catalytic sites.From this,it will be seen that single regulation of metal active centers is difficult to comprehensively solve application problems.Orderly assembly and coordination of catalyst multi-hierarchy structures at the mesoscale above the nanometer level probably be more reasonable strategies,and numerous studies in thermal catalysis have supported this viewpoint.This article reviews the multi-hierarchy design of electrocatalyst active centers,high-energy supports,and peripheral structures in recent years,providing unconventional inspiration about electrocatalyst creation,which perhaps serves as a simple tutorial of electrocatalysis exploration for abecedarian.
基金Project supported by the National Basic Research Program of China(973 Program)(Grant No.2013CB922200)the National Natural Science Foundation of China(Grant Nos.11034003,11074095,and 11274140)+1 种基金the Natural Science Foundation of Heilongjiang Province,China(Grant No.QC2011C092)the Scientific Research Fund of Heilongjiang Provincial Education Department,China(Grant No.12531751)
文摘Carbon monosulfide molecular ion (CS+), which plays an important role in various research fields, has long been attracting much interest. Because of the unstable and transient nature of CS+, its electronic states have not been well investigated. In this paper, the electronic states of CS+ are studied by employing the internally contracted multireference configuration interaction method, and taking into account relativistic effects (scalar plus spin–orbit coupling). The spin–orbit coupling effects are considered via the state-interacting method with the full Breit–Pauli Hamiltonian. The potential energy curves of 18 Λ–S states correlated with the two lowest dissociation limits of CS+ molecular ion are calculated, and those of 10 lowest Ω states generated from the 6 lowest Λ–S states are also worked out. The spectroscopic constants of the bound states are evaluated, and they are in good agreement with available experimental results and theoretical values. With the aid of analysis of Λ–S composition of Ω states at different bond lengths, the avoided crossing phenomena in the electronic states of CS+ are illuminated. Finally, the single ionization spectra of CS (X1Σ+) populating the CS+(X2Σ1/2+, A2Π3/2, A2Π1/2, and B2Σ1/2+) states are simulated. The vertical ionization potentials for X2Σ1/2+, A2Π3/2, A2Π1/2, and B2Σ1/2+ states are calculated to be 11.257, 12.787, 12.827, and 15.860 eV, respectively, which are accurate compared with previous experimental results, within an error margin of 0.08 eV^0.2 eV.
基金Financial support from the National Natural Science Foundation of China (No.50773063)National Basic Research Program of China(2010CB635111)Basic Research of National Defence are highly appreciated
文摘Molecular simulation was performed to study the interaction between CaCO3 crystal and several oligomer inhibitors, by using the equilibrium morphology method to calculate the growth morphology of CaCO3 without inhibitors. The calculated morphology agreed well with SEM photographs. Then, a double-layer model was built to investigate the interaction between calcite crystal and oligomer inhibitors containing maleic anhydride (MA) and acrylic acid (AA). Interaction energy per gram of an oligomer inhibitor was introduced as a scale of inhibition efficiency of different monomers. The results indicated that, for calcite scale inhibition, acrylamide (AM) and vinyl phosphonic acid (VPA) were the most efficient monomers, while allylsulfonic acid (AS) was the poorest. Increasing proportion of AM in dimer inhibitor molecule would improve the inhibition efficiency of MA, though, for a trimer, such as MA-AA-AM, certain sequence of monomers in the inhibitor molecule was necessary besides higher proportion of AM.
基金supported financially by the National Natural Science Foundation of China (Nos. 21302212 and 21522209)the ‘‘Strategic Priority Research Program’’ (No. XDB12010100)
文摘A series of core-expanded naphthalene diimides(NDI-DTYM) and thiophene-based derivatives(1a-c)were designed and synthesized to investigate the relationship between molecular structures and the highest occupied molecular orbital(HOMO) energy levels but has little impact on the lowest unoccupied molecular orbital(LUMO) energy levels.The results demonstrated that increasing the number of thiophene units can gradually elevate the HOMO energy levels but had little impact on the LUMO energy levels.The n-channel organic field-effect transistors(OFETs) based on 1b and 1c have demonstrated that these almost unchanged LUMO energy levels are proper to transport electrons.
基金the National Natural Science Foundation of China(NSFC)(Grant No.11875049)the NSAF(Grant Nos.U1730449 and U1930403)the National Basic Research Program of China(Grant No.2016YFA0301201).
文摘In scanning tunneling microscopy-induced luminescence(STML),the photon count is measured to reflect single-molecule properties,e.g.,the first molecular excited state.The energy of the first excited state is typically shown by a rise of the photon count as a function of the bias voltage between the tip and the substrate.It remains a challenge to determine the precise rise position of the current due to possible experimental noise.In this work,we propose an alternating current version of STML to resolve the fine structures in the photon count measurement.The measured photon count and the current at the long-time limit show a sinusoidal oscillation.The zero-frequency component of the current shows knee points at the precise voltage as the fraction of the detuning between the molecular gap and the DC component of the bias voltage.We propose to measure the energy level with discontinuity of the first derivative of such a zero-frequency component.The current method will extend the application of STML in terms of measuring molecular properties.
基金support of National Natural Science Foundation of China(21975107)Natural Science Foundation of Jiangsu Province(SBK2019020945)+2 种基金National First-Class Discipline Program of Light Industry Technology and Engineering(LITE2018-21)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX20_1783)China Scholarship Council(202006790096).
文摘A large of energy consumption is required for indoor and outdoor personal heating to ameliorate the comfortable and healthy conditions.Main personal thermal management strategy is to reflect mid-infrared human body radiation for human surface temperature(THS)regulation.We demonstrate a visible Janus light absorbent/reflective air-layer fabric(Janus A/R fabric)that can passively reflect radiative heating meanwhile can actively capture the solar energy.A series of azobenzene derivatives functionalized with alkyl tails are reported to co-harvest the solar and phase-change energy.The THS covered by Janus A/R fabric can be heated up to~3.7°C higher than that covered by air-layer fabric in cold environment(5°C).Besides,integrating the thermo-and photo-chromic properties is capable of monitoring comfort THS and residue energy storage enthalpy,respectively.According to the colour monitors,intermittent irradiation approach is proposed to prolong comfortable-THS holding time for managing energy efficiently.
基金the Natural Science Foundation of China(No. 51072239)the Fundamental Research Funds for the Central Universities(No.CQDXWL-2012-032) for financial support
文摘Based on the generalized gradient approximation (GGA), Perdew-Wang-91 (PW91) combined with a periodic slab model has been applied to study the catalytic activity of chlorine evolution on TinRumO2 (1 1 0) surface. Metal oxide model TinRumO2 has been established with pure TiO2 and Ru02 on the basis set of Double Numerical plus polarization (DNP), in which the proportion of n:m was 3:1, 1 :l, or 1:3. Analysis on the reaction activity in the electrochemical reaction and the electrochemical desorption reaction was based on Frontier molecular orbital theory. The results show that the TinRumO2 with a ratio of Ti:Ru at 3:1 is best facilitates the electrochemical reaction and electrochemical desorption reaction to produce M-Clads intermediate and precipitate C12. In addition, the adsorption energy of Cl on the surface of Ti3RU102 possesses the minimum value of 2.514 eV, and thus electrochemical desorption reaction could occur most easily.
文摘The energies, geometries and harmonic vibrational frequencies of 1 : 1 5-hydroxytryptamine-water (5-HT-H20) complexes are studied at the MP2/6-311 + + G(d,p) level. Natural bond orbital (NBO), quantum theory of atoms in molecules (QTAIM) analyses and the localized molecular orbital energy decomposition analysis (LMO-EDA) were performed to explore the nature of the hydrogen-bonding interactions in these complexes. Various types of hydro- gen bonds (H-bonds) are formed in these 5-HT-H20 complexes. The intermolecular C4H55HT'"Ow H-bond in HTW3 is strengthened due to the cooperativity, whereas no such cooperativity is found in the other 5-HT-H20 complexes. H-bond in which nitrogen atom of amino in 5-HT acted as proton donors was stronger than other H-bonds. Our researches show that the hydrogen bonding interaction plays a vital role on the relative stabilities of 5-HT-H20 complexes.
基金supported by National Natural Science Foundation of China(No.21275043)National Basic Research Program of China under Grants(No.2009CB421601)
文摘Designing molecular logic gates to operate programmably for molecular diagnostics in molecular computing still remains challenging.Here,we designed a novel linear DNA logic gates for microRNA analysis based on strand displacement and fluorescence resonance energy transfer(FRET).Two labeled strands closed each other produce to FRET through hybridization with a complementary strand to form a basic work unit of logic gate.Two indicators of heart failure(microRNA-195 and microRNA-21) were selected as the logic inputs and the fluorescence mode was used as the logic output.We have demonstrated that the molecular logic gate mechanism worked well with the construction of YES and AND gates.
文摘Hand,foot,and mouth disease(HFMD),primarily instigated by Coxsackievirus A16(CVA16),poses a serious health concern,necessitating effective therapeutic interventions.The RNA-dependent RNA polymerase(RdRp)of CVA16 emerges as a promising drug target for HFMD treatment.This study presents an in-silico pipeline for the identification of potential RdRp inhibitors against CVA16.A library of 91 natural compounds derived from Bacopa monnieri(brahmi)was virtually screened against the CVA16 RdRp.Here,Bacobitacin D emerged as a promising hit molecule,forming 8 hydrogen bonds including key catalytic site residues(Asp^(238)and Asp^(329))within the RdRp active site.Further,molecular dynamics(MD)simulations and MM/GBSA binding free energy calculations was applied on the top three hits that were selected based on exhaustive docking scores(≤-9.55 kcal/mol).Bacobitacin D exhibited sustainable stability,as evidenced by minimal deviation(RMSD=0.75±0.02 nm)during a 100 ns MD simulation.Importantly,Bacopaside IV exhibited the lowestΔGTOTAL binding free energy(-23.70 kcal/mol),while Bacobitacin D displayed a comparableΔGTOTAL of19.14 kcal/mol.Structural interpretation of the most populated cluster derived from MD simulations showed direct interactions of Bacobitacin D with pivotal catalytic residues,including Asp^(238)and Ser^(289).This comprehensive study confirmed Bacobitacin D as a potent inhibitor of CVA16 RdRp,offering a potential avenue for therapeutic intervention against HFMD.Experimental validation is required to confirm the inhibitory action of Bacobitacin D against HFMD.