Global minimization algorithm is indispensable to solving the protein folding problem based upon thermodynamic hypothesis. Here we propose a pseudo potential function, contact difference(CD), for simulating empirical ...Global minimization algorithm is indispensable to solving the protein folding problem based upon thermodynamic hypothesis. Here we propose a pseudo potential function, contact difference(CD), for simulating empirical contact potential functions and testing global minimization algorithm. The present paper covers conformational sampling and global minimization algorithm called BML03, based upon Monte Carlo and simulated annealing, which is able to locate CD′s global minimum and refold extended protein structures into ones with root mean square distance(RMSD) as small as 0.03 nm from the native structures. For empirical contact potential functions, these results demonstrate that their global minimization problems may be solvable.展开更多
Global minimization algorithm is indispensable for solving protein folding problems based on thermodynamic hypothesis. A contact difference （CD） based on pseudo potential function, for simulating empirical contact p...Global minimization algorithm is indispensable for solving protein folding problems based on thermodynamic hypothesis. A contact difference （CD） based on pseudo potential function, for simulating empirical contact potential functions and testing global minimization algorithm was proposed. The present article describes a conformational sampiing and global minimization algorithm, which is called WL, based on Monte Carlo simulation and simulated annealing. It can be used to locate CD＇s globe minimum and refold extended protein structures, as small as 0. 03 nm, from the native structures, back to ones with root mean square distance（RMSD）. These results demonstrate that the global minimization problems for empirical contact potential functions may be solvable.展开更多
Additive engineering significantly enhances the photovoltaic performance of perovskite solar cells(PSCs).The atomistic and mechanistic origins of these jfurther investigation to fully understand the physicochemical in...Additive engineering significantly enhances the photovoltaic performance of perovskite solar cells(PSCs).The atomistic and mechanistic origins of these jfurther investigation to fully understand the physicochemical interactions of additives with the perovskite lattice,band structure,and charge carriers.Herein,how additives of cellulose triacetate(CTA)improve the photovoltaic performance and stability of perovskite solar cells(PSCs)is shown.These improvements are found to stem from the formation of hydrogen bonds between CTA molecules and organic cations.The Kelvin probe force microscopy results show that contact potential difference variation under dark and light conditions increases from 79.68 to 141.24 mV by doping CTA,indicating enhanced separation of electron-hole pairs in perovskite.The piezoresponse force microscopy(PFM)tests indicate that CTA additives reduce the PFM amplitude by approximately 50 pm under dark and light conditions and inhibit flipping from antiferroelectric domains to ferroelectric domains.Moreover,the CTA additives regulate the charge distribution within the PbI6 octahedron and bind organic ions through hydrogen bonding,forming a compact film structure.These findings not only improve the long-term stability of organic-inorganic hybrid perovskites(OIHPs),but also pave the way for developing novel strategies for large-scale PSCs.展开更多
The determination of discontinuity shear strength is an important concern in rock engineering.Previous research mainly focused on the shear behavior of discontinuities with identical joint wall compressive strengths(D...The determination of discontinuity shear strength is an important concern in rock engineering.Previous research mainly focused on the shear behavior of discontinuities with identical joint wall compressive strengths(DIJCS).However,the shear behavior of discontinuities with different joint wall compressive strengths(DDJCS)and 3D surface morphology had been rarely reported.In this study,matched mortar DDJCSs were prepared using 3D printed photosensitive resin molds.Direct shear tests were carried out under three kinds of normal stress(ranging from 0.5 to 3.0 MPa)to analyze the shear strength and contact zones of DDJCS during shearing.The results show that the contact zones of DDJCS during shearing are scattered in the steep zones facing the shear direction.It is verified that Grasselli and Develi’s directional surface roughness characterization method can be used to predict the shear-induced potential contact zones of DDJCS.When the critical apparent dip angle is equal to the peak dilation angle,the predicted contact area agrees well with the actual contact area.A 3D directional roughness parameter with clear physical meaning was introduced to characterize discontinuity surface roughness.A 3D modified joint roughness coefficient-joint wall compressive strength(JRC-JCS)criterion that can both predict the shear strength of DDJCS and DIJCS was proposed based on the newly defined roughness parameter.The proposed criterion was validated by 77 direct shear tests presented by this study and 163 direct shear tests presented by other investigators.The results show that the proposed criterion was generally reliable for the peak shear strength prediction of DDJCS and DIJCS(within 16%).It is also found that the new criterion can capture the anisotropy of the peak shear strength of DDJCS.The anisotropy of DDJCS decreases with increasing normal stress.It should be noted that the anisotropy of the shear strength of DDJCS was not investigated experimentally,and further experiments should be conducted to verify it.展开更多
Semiconductor/metal junctions are widely discussed in photocatalysis.However,there is a notable scarcity of systematic studies focusing on photogenerated charge carrier transfer in such junctions.Herein,CdS/Pt,CdS/Au,...Semiconductor/metal junctions are widely discussed in photocatalysis.However,there is a notable scarcity of systematic studies focusing on photogenerated charge carrier transfer in such junctions.Herein,CdS/Pt,CdS/Au,and CdS/Ag are synthesized to serve as model systems for investigating the charge carrier transfer in semiconductor/metal junctions.Kelvin probe force microscopy is employed to visualize the transfer of photogenerated carriers in these materials.The results show that the electron transfer behavior under illumination is related to the conduction band position of CdS and the Fermi level position of the metal.Moreover,Schottky junctions hinder the transfer of photogenerated electrons from CdS to Pt and Au,whereas ohmic contacts facilitate the transfer of photogenerated electrons from CdS to Ag.This work provides novel insights into the mechanisms governing the transfer of photogenerated carriers in semiconductor/metal junctions.展开更多
Protein protein recognition is an important step in biological processes, which still largely remains elusive. The inter residue contact potential, CP ij , describes the propensity of contact between two type...Protein protein recognition is an important step in biological processes, which still largely remains elusive. The inter residue contact potential, CP ij , describes the propensity of contact between two types of residue. In this study, several different CP ij variants were examined with the objective of discriminating the binding potential of surface pairs. Using solvent mediated inter molecule contact potential (SM IMCP ij ), an evaluation model was deduced and tested. Using the evaluation model it was found that the SM IMCP ij gives a better performance than either residue mediated IMCP ij (RM IMCP ij ) or folding residue contact potential (FCP ij ). The results suggest that the evaluation model provides a fast, effective, and discriminative method for the evaluation of proposed binding interfaces.展开更多
基金Supported by the National Natural Science Foundation of China(No.30 2 4 0 0 16)
文摘Global minimization algorithm is indispensable to solving the protein folding problem based upon thermodynamic hypothesis. Here we propose a pseudo potential function, contact difference(CD), for simulating empirical contact potential functions and testing global minimization algorithm. The present paper covers conformational sampling and global minimization algorithm called BML03, based upon Monte Carlo and simulated annealing, which is able to locate CD′s global minimum and refold extended protein structures into ones with root mean square distance(RMSD) as small as 0.03 nm from the native structures. For empirical contact potential functions, these results demonstrate that their global minimization problems may be solvable.
文摘Global minimization algorithm is indispensable for solving protein folding problems based on thermodynamic hypothesis. A contact difference （CD） based on pseudo potential function, for simulating empirical contact potential functions and testing global minimization algorithm was proposed. The present article describes a conformational sampiing and global minimization algorithm, which is called WL, based on Monte Carlo simulation and simulated annealing. It can be used to locate CD＇s globe minimum and refold extended protein structures, as small as 0. 03 nm, from the native structures, back to ones with root mean square distance（RMSD）. These results demonstrate that the global minimization problems for empirical contact potential functions may be solvable.
基金supported by the National Natural Science Foundation of China(No.U2130128)Yanzhao Young Scientist Project from Natural Science Foundation of Hebei Province(Nos.B2023205040)+4 种基金Basic Research Cooperation Special Foundation of Beijing-Tianjin-Hebei Region(Nos.H2022205047,22JCZXJC00060 and E3B33911DF)Hebei Administration for Market Supervision Science and Technology Project List(No.2023ZC03)the Innovation Capability Improvement Plan Project of Hebei Province(No.22567604H)Ph.D.Scientific Research Start-up Fund of Hebei Normal University(No.L2023B18)College Student’s Innovation and Entrepreneurship Training Plan Program(No.S202410094046).
文摘Additive engineering significantly enhances the photovoltaic performance of perovskite solar cells(PSCs).The atomistic and mechanistic origins of these jfurther investigation to fully understand the physicochemical interactions of additives with the perovskite lattice,band structure,and charge carriers.Herein,how additives of cellulose triacetate(CTA)improve the photovoltaic performance and stability of perovskite solar cells(PSCs)is shown.These improvements are found to stem from the formation of hydrogen bonds between CTA molecules and organic cations.The Kelvin probe force microscopy results show that contact potential difference variation under dark and light conditions increases from 79.68 to 141.24 mV by doping CTA,indicating enhanced separation of electron-hole pairs in perovskite.The piezoresponse force microscopy(PFM)tests indicate that CTA additives reduce the PFM amplitude by approximately 50 pm under dark and light conditions and inhibit flipping from antiferroelectric domains to ferroelectric domains.Moreover,the CTA additives regulate the charge distribution within the PbI6 octahedron and bind organic ions through hydrogen bonding,forming a compact film structure.These findings not only improve the long-term stability of organic-inorganic hybrid perovskites(OIHPs),but also pave the way for developing novel strategies for large-scale PSCs.
基金Project(GZB202405561)supported by the China Postdoctoral Fellowship ProgramProject(42377154)supported by the National Natural Science Foundation of China。
文摘The determination of discontinuity shear strength is an important concern in rock engineering.Previous research mainly focused on the shear behavior of discontinuities with identical joint wall compressive strengths(DIJCS).However,the shear behavior of discontinuities with different joint wall compressive strengths(DDJCS)and 3D surface morphology had been rarely reported.In this study,matched mortar DDJCSs were prepared using 3D printed photosensitive resin molds.Direct shear tests were carried out under three kinds of normal stress(ranging from 0.5 to 3.0 MPa)to analyze the shear strength and contact zones of DDJCS during shearing.The results show that the contact zones of DDJCS during shearing are scattered in the steep zones facing the shear direction.It is verified that Grasselli and Develi’s directional surface roughness characterization method can be used to predict the shear-induced potential contact zones of DDJCS.When the critical apparent dip angle is equal to the peak dilation angle,the predicted contact area agrees well with the actual contact area.A 3D directional roughness parameter with clear physical meaning was introduced to characterize discontinuity surface roughness.A 3D modified joint roughness coefficient-joint wall compressive strength(JRC-JCS)criterion that can both predict the shear strength of DDJCS and DIJCS was proposed based on the newly defined roughness parameter.The proposed criterion was validated by 77 direct shear tests presented by this study and 163 direct shear tests presented by other investigators.The results show that the proposed criterion was generally reliable for the peak shear strength prediction of DDJCS and DIJCS(within 16%).It is also found that the new criterion can capture the anisotropy of the peak shear strength of DDJCS.The anisotropy of DDJCS decreases with increasing normal stress.It should be noted that the anisotropy of the shear strength of DDJCS was not investigated experimentally,and further experiments should be conducted to verify it.
基金supported by the National Key Research and Development Program of China(No.2022YFB3803600)the National Natural Science Foundation of China(Nos.22238009,51932007,U1905215,52073223,22278324,52272290,52173065,and 22202187)+2 种基金the Natural Science Foundation of Hubei Province of China(No.2022CFA001)the National Postdoctoral Program for Innovative Talents(No.BX2021275)the Project funded by China Postdoctoral Science Foundation(No.2022M712957).
文摘Semiconductor/metal junctions are widely discussed in photocatalysis.However,there is a notable scarcity of systematic studies focusing on photogenerated charge carrier transfer in such junctions.Herein,CdS/Pt,CdS/Au,and CdS/Ag are synthesized to serve as model systems for investigating the charge carrier transfer in semiconductor/metal junctions.Kelvin probe force microscopy is employed to visualize the transfer of photogenerated carriers in these materials.The results show that the electron transfer behavior under illumination is related to the conduction band position of CdS and the Fermi level position of the metal.Moreover,Schottky junctions hinder the transfer of photogenerated electrons from CdS to Pt and Au,whereas ohmic contacts facilitate the transfer of photogenerated electrons from CdS to Ag.This work provides novel insights into the mechanisms governing the transfer of photogenerated carriers in semiconductor/metal junctions.
基金Supported by the National Natural Science Foundation (No.39970 15 5 ) the High- Technology Developm entProgram of China (No.2 0 0 1AA 2 330 11) +1 种基金and theNational Frontier Research Program (No.G19990 75 6 0 2 G19990 1190 2 and19980 5 110 5 )
文摘Protein protein recognition is an important step in biological processes, which still largely remains elusive. The inter residue contact potential, CP ij , describes the propensity of contact between two types of residue. In this study, several different CP ij variants were examined with the objective of discriminating the binding potential of surface pairs. Using solvent mediated inter molecule contact potential (SM IMCP ij ), an evaluation model was deduced and tested. Using the evaluation model it was found that the SM IMCP ij gives a better performance than either residue mediated IMCP ij (RM IMCP ij ) or folding residue contact potential (FCP ij ). The results suggest that the evaluation model provides a fast, effective, and discriminative method for the evaluation of proposed binding interfaces.
