The fusion excitation functions for 12 colliding systems with 96≤Z_(1)Z_(2)≤608 are analyzed using coupled-channel(CC)calculations based on the M3Y double-folding(DF)potential supplemented with a repulsive potential...The fusion excitation functions for 12 colliding systems with 96≤Z_(1)Z_(2)≤608 are analyzed using coupled-channel(CC)calculations based on the M3Y double-folding(DF)potential supplemented with a repulsive potential that takes into account the incompressibility of the nuclear matter.We also applied the polarization effects of hot nuclear matter(PEHNM)on the calculations of the bare nucleus-nucleus interaction potential within the framework of the modified density-dependent Seyler-Blanchard(SB)approach in the T^(2)approximation.Our results reveal that we obtain a nice description of the experimental data of different fusion systems when we use the present theoretical approach to calculate the energy-dependent values of the fusion cross sections.In this paper,the influence of the PEHNM on the surface diffuseness parameter of the Woods-Saxon(WS)potential is also studied.In order to reach this goal,we extract the corresponding values of this parameter based on the modified form of the DF potential(M3Y+Repulsion+polarization).We find that the extracted values are located in a range between a=0.61 and 0.80 fm at different incident energies.It seems that the polarization effects of hot nuclear matter play a key role in describing the abnormally large values of the nuclear potential diffusenesses in the heavy-ion fusion reactions.Additionally,the regular decreasing trend for the diffuseness parameter of the nucleus-nucleus potential with the increase in the bombarding energies is also observed.展开更多
A radial basis function network(RBFN)approach is adopted for the first time to optimize the calculation of$\alpha$decay half-life in the generalized liquid drop model(GLDM),while concurrently incorporating the surface...A radial basis function network(RBFN)approach is adopted for the first time to optimize the calculation of$\alpha$decay half-life in the generalized liquid drop model(GLDM),while concurrently incorporating the surface diffuseness effect.The calculations presented herein agree closely with the experimental half-lives for 68 superheavy nuclei(SHN),achieving a remarkable reduction of 40%in the root-mean-square(rms)deviations of half-lives.Furthermore,using the RBFN method,the half-lives for four SHN isotopes,252-288Rf,272-310Fl,286-316119,and 292-318120,are predicted using the improved GLDM with the diffuseness correction and the decay energies from WS4 and FRDM as inputs.Therefore,we conclude that the diffuseness effect should be embodied in the proximity energy.Moreover,increased application of neural network methods in nuclear reaction studies is encouraged.展开更多
A medical image encryption is proposed based on the Fisher-Yates scrambling,filter diffusion and S-box substitution.First,chaotic sequence associated with the plaintext is generated by logistic-sine-cosine system,whic...A medical image encryption is proposed based on the Fisher-Yates scrambling,filter diffusion and S-box substitution.First,chaotic sequence associated with the plaintext is generated by logistic-sine-cosine system,which is used for the scrambling,substitution and diffusion processes.The three-dimensional Fisher-Yates scrambling,S-box substitution and diffusion are employed for the first round of encryption.The chaotic sequence is adopted for secondary encryption to scramble the ciphertext obtained in the first round.Then,three-dimensional filter is applied to diffusion for further useful information hiding.The key to the algorithm is generated by the combination of hash value of plaintext image and the input parameters.It improves resisting ability of plaintext attacks.The security analysis shows that the algorithm is effective and efficient.It can resist common attacks.In addition,the good diffusion effect shows that the scheme can solve the differential attacks encountered in the transmission of medical images and has positive implications for future research.展开更多
The interdiffusion coefficients in Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys were efficiently determined by combining diffusion couple experiments and high-throughput determination of ...The interdiffusion coefficients in Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys were efficiently determined by combining diffusion couple experiments and high-throughput determination of interdiffusion coefficients(HitDIC)software at 1273−1373 K.The results show that the addition of Al,Cu,and Mn to CoCrFeNi high-entropy alloys promotes the diffusion of Co,Cr,and Fe atoms.The comparison of tracer diffusion coefficients indicates that there is no sluggish diffusion in tracer diffusion on the thermodynamic temperature scale for the present Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys.The linear relationship between diffusion entropy and activation energy reveals that the diffusion process of atoms is unaffected by an increase in the number of components as long as the crystal structure remains unchanged.展开更多
The combination of dual-main-phase(DMP)(Nd,Ce)-Fe-B magnets and grain boundary diffusion process(GBDP)is currently a research topic for obtaining high-cost performance materials in rare earth permanent magnet fields.T...The combination of dual-main-phase(DMP)(Nd,Ce)-Fe-B magnets and grain boundary diffusion process(GBDP)is currently a research topic for obtaining high-cost performance materials in rare earth permanent magnet fields.The novel structural features of GBDP(Nd,Ce)-Fe-B magnets give a version of different domain reversal processes from those of non-diffused magnets.In this work,the in-situ magnetic domain evolution of the DMP magnets was observed at elevated temperatures,and the temperature demagnetization and coercivity mechanism of the GBDP dual-main-phase(Nd,Ce)-Fe-B magnets are discussed.The results show that the shell composition of different types of grains in DMP magnets is similar,while the magnetic microstructure results indicate the Ce-rich grains tend to demagnetize first.Dy-rich shell with a high anisotropic field caused by GBDP leads to an increase in the nucleation field,which enhances the coercivity.It is found that much more grains exhibit single domain characteristics in the remanent state for GBDP dual-main-phase(Nd,Ce)-Fe-B magnets.In addition,the grains that undergo demagnetization first are Ce-rich or Nd-rich grains,which is different from that of non-diffused magnets.These results were not found in previous studies but can be intuitively characterized from the perspective of magnetic domains in this work,providing a new perspective and understanding of the performance improvement of magnetic materials.展开更多
A pyrimidine derivative,6-phenyl-2-thiouracil(PT),was synthesized for developing a corrosion inhibitor(CI)applied in the protection of the nickel−aluminum bronze(NAB)in seawater.The anti-corrosion effect of PT was eva...A pyrimidine derivative,6-phenyl-2-thiouracil(PT),was synthesized for developing a corrosion inhibitor(CI)applied in the protection of the nickel−aluminum bronze(NAB)in seawater.The anti-corrosion effect of PT was evaluated by the mass loss experiment,electrochemical tests and surface analysis.The results show that PT exhibits excellent inhibition performance and the maximum inhibition efficiency of PT reaches 99.6%.The interaction mechanism was investigated through X-ray photoelectron spectroscopy(XPS)and molecule dynamics simulation based on the density functional theory(DFT).The S-Cu,Al-N and Cu-N bonds are formed by the chemical interactions,leading to the adsorption of PT on the NAB surface.The diffusion of corrosive species is hindered considerably by the protective PT film with composition of(PT-Cu)_(ads)and(PT-Al)_(ads)on the PT/NAB interface.The degree of suppression is increased with the addition of more PT molecules.展开更多
Recently,diffusion models have emerged as a promising paradigm for molecular design and optimization.However,most diffusion-based molecular generative models focus on modeling 2D graphs or 3D geom-etries,with limited ...Recently,diffusion models have emerged as a promising paradigm for molecular design and optimization.However,most diffusion-based molecular generative models focus on modeling 2D graphs or 3D geom-etries,with limited research on molecular sequence diffusion models.The International Union of Pure and Applied Chemistry(IUPAC)names are more akin to chemical natural language than the simplified molecular input line entry system(SMILES)for organic compounds.In this work,we apply an IUPAC-guided conditional diffusion model to facilitate molecular editing from chemical natural language to chemical language(SMILES)and explore whether the pre-trained generative performance of diffusion models can be transferred to chemical natural language.We propose DiffIUPAC,a controllable molecular editing diffusion model that converts IUPAC names to SMILES strings.Evaluation results demonstrate that our model out-performs existing methods and successfully captures the semantic rules of both chemical languages.Chemical space and scaffold analysis show that the model can generate similar compounds with diverse scaffolds within the specified constraints.Additionally,to illustrate the model’s applicability in drug design,we conducted case studies in functional group editing,analogue design and linker design.展开更多
文摘The fusion excitation functions for 12 colliding systems with 96≤Z_(1)Z_(2)≤608 are analyzed using coupled-channel(CC)calculations based on the M3Y double-folding(DF)potential supplemented with a repulsive potential that takes into account the incompressibility of the nuclear matter.We also applied the polarization effects of hot nuclear matter(PEHNM)on the calculations of the bare nucleus-nucleus interaction potential within the framework of the modified density-dependent Seyler-Blanchard(SB)approach in the T^(2)approximation.Our results reveal that we obtain a nice description of the experimental data of different fusion systems when we use the present theoretical approach to calculate the energy-dependent values of the fusion cross sections.In this paper,the influence of the PEHNM on the surface diffuseness parameter of the Woods-Saxon(WS)potential is also studied.In order to reach this goal,we extract the corresponding values of this parameter based on the modified form of the DF potential(M3Y+Repulsion+polarization).We find that the extracted values are located in a range between a=0.61 and 0.80 fm at different incident energies.It seems that the polarization effects of hot nuclear matter play a key role in describing the abnormally large values of the nuclear potential diffusenesses in the heavy-ion fusion reactions.Additionally,the regular decreasing trend for the diffuseness parameter of the nucleus-nucleus potential with the increase in the bombarding energies is also observed.
基金Supported by the National Natural Science Foundation of China(11947229,11675223,11675066)the China Postdoctoral Science Foundation(2019M663853)the Fundamental Research Funds for the Central Universities(lzujbky-2017-ot04)and Feitian Scholar Project of Gansu province。
文摘A radial basis function network(RBFN)approach is adopted for the first time to optimize the calculation of$\alpha$decay half-life in the generalized liquid drop model(GLDM),while concurrently incorporating the surface diffuseness effect.The calculations presented herein agree closely with the experimental half-lives for 68 superheavy nuclei(SHN),achieving a remarkable reduction of 40%in the root-mean-square(rms)deviations of half-lives.Furthermore,using the RBFN method,the half-lives for four SHN isotopes,252-288Rf,272-310Fl,286-316119,and 292-318120,are predicted using the improved GLDM with the diffuseness correction and the decay energies from WS4 and FRDM as inputs.Therefore,we conclude that the diffuseness effect should be embodied in the proximity energy.Moreover,increased application of neural network methods in nuclear reaction studies is encouraged.
文摘A medical image encryption is proposed based on the Fisher-Yates scrambling,filter diffusion and S-box substitution.First,chaotic sequence associated with the plaintext is generated by logistic-sine-cosine system,which is used for the scrambling,substitution and diffusion processes.The three-dimensional Fisher-Yates scrambling,S-box substitution and diffusion are employed for the first round of encryption.The chaotic sequence is adopted for secondary encryption to scramble the ciphertext obtained in the first round.Then,three-dimensional filter is applied to diffusion for further useful information hiding.The key to the algorithm is generated by the combination of hash value of plaintext image and the input parameters.It improves resisting ability of plaintext attacks.The security analysis shows that the algorithm is effective and efficient.It can resist common attacks.In addition,the good diffusion effect shows that the scheme can solve the differential attacks encountered in the transmission of medical images and has positive implications for future research.
基金supported by the National Natural Science Foundation of China(No.52374372)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.23KJB430042)+3 种基金the Jiangsu Province Large Scientific Instruments Open Sharing Autonomous Research Filing Project,China(No.TC2023A037)the Yangzhou City−Yangzhou University Cooperation Foundation,China(No.YZ2022183)High-end Talent Support Program of Yangzhou University,China,Qinglan Project of Yangzhou University,ChinaLvyangjinfeng Talent program of Yangzhou,China.
文摘The interdiffusion coefficients in Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys were efficiently determined by combining diffusion couple experiments and high-throughput determination of interdiffusion coefficients(HitDIC)software at 1273−1373 K.The results show that the addition of Al,Cu,and Mn to CoCrFeNi high-entropy alloys promotes the diffusion of Co,Cr,and Fe atoms.The comparison of tracer diffusion coefficients indicates that there is no sluggish diffusion in tracer diffusion on the thermodynamic temperature scale for the present Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys.The linear relationship between diffusion entropy and activation energy reveals that the diffusion process of atoms is unaffected by an increase in the number of components as long as the crystal structure remains unchanged.
基金supported by the National Key Research and Development Program of China(Nos.2021YFB3503003,2021YFB3503100,and 2022YFB3505401).
文摘The combination of dual-main-phase(DMP)(Nd,Ce)-Fe-B magnets and grain boundary diffusion process(GBDP)is currently a research topic for obtaining high-cost performance materials in rare earth permanent magnet fields.The novel structural features of GBDP(Nd,Ce)-Fe-B magnets give a version of different domain reversal processes from those of non-diffused magnets.In this work,the in-situ magnetic domain evolution of the DMP magnets was observed at elevated temperatures,and the temperature demagnetization and coercivity mechanism of the GBDP dual-main-phase(Nd,Ce)-Fe-B magnets are discussed.The results show that the shell composition of different types of grains in DMP magnets is similar,while the magnetic microstructure results indicate the Ce-rich grains tend to demagnetize first.Dy-rich shell with a high anisotropic field caused by GBDP leads to an increase in the nucleation field,which enhances the coercivity.It is found that much more grains exhibit single domain characteristics in the remanent state for GBDP dual-main-phase(Nd,Ce)-Fe-B magnets.In addition,the grains that undergo demagnetization first are Ce-rich or Nd-rich grains,which is different from that of non-diffused magnets.These results were not found in previous studies but can be intuitively characterized from the perspective of magnetic domains in this work,providing a new perspective and understanding of the performance improvement of magnetic materials.
基金supported by the National Natural Science Foundation of China(No.52171069).
文摘A pyrimidine derivative,6-phenyl-2-thiouracil(PT),was synthesized for developing a corrosion inhibitor(CI)applied in the protection of the nickel−aluminum bronze(NAB)in seawater.The anti-corrosion effect of PT was evaluated by the mass loss experiment,electrochemical tests and surface analysis.The results show that PT exhibits excellent inhibition performance and the maximum inhibition efficiency of PT reaches 99.6%.The interaction mechanism was investigated through X-ray photoelectron spectroscopy(XPS)and molecule dynamics simulation based on the density functional theory(DFT).The S-Cu,Al-N and Cu-N bonds are formed by the chemical interactions,leading to the adsorption of PT on the NAB surface.The diffusion of corrosive species is hindered considerably by the protective PT film with composition of(PT-Cu)_(ads)and(PT-Al)_(ads)on the PT/NAB interface.The degree of suppression is increased with the addition of more PT molecules.
基金supported by the Yonsei University graduate school Department of Integrative Biotechnology.
文摘Recently,diffusion models have emerged as a promising paradigm for molecular design and optimization.However,most diffusion-based molecular generative models focus on modeling 2D graphs or 3D geom-etries,with limited research on molecular sequence diffusion models.The International Union of Pure and Applied Chemistry(IUPAC)names are more akin to chemical natural language than the simplified molecular input line entry system(SMILES)for organic compounds.In this work,we apply an IUPAC-guided conditional diffusion model to facilitate molecular editing from chemical natural language to chemical language(SMILES)and explore whether the pre-trained generative performance of diffusion models can be transferred to chemical natural language.We propose DiffIUPAC,a controllable molecular editing diffusion model that converts IUPAC names to SMILES strings.Evaluation results demonstrate that our model out-performs existing methods and successfully captures the semantic rules of both chemical languages.Chemical space and scaffold analysis show that the model can generate similar compounds with diverse scaffolds within the specified constraints.Additionally,to illustrate the model’s applicability in drug design,we conducted case studies in functional group editing,analogue design and linker design.
