Moral generalism and particularism are two positions in meta-ethics which have different views regarding the relation between moral thought and principles. By accepting this relationship, generalists emphasize the nec...Moral generalism and particularism are two positions in meta-ethics which have different views regarding the relation between moral thought and principles. By accepting this relationship, generalists emphasize the necessity of principles in decision making process, and claim that the rationality of moral thought depends on the provision of a suitable supply ofmoral principles. In contrast, particularists have rejected, or at least doubted, the existence of moral principles, and believe that the rationality of moral thought depends on recognizing special features of a case and relevant conditions. This is why, unlike generalists, they use case study method rather than syllogism in decision making process and moral judgment. Consequently, to support their view, particularists commonly resort to holism in the theory of reasons, while atomism is in support of generalism. To evaluate these two attitudes, this study surveys some arguments that particularists and generalists proposed to justify their view and criticize the rival＇s one, and also explains their positions concerning the epistemological and metaphysical role of moral principles and reasons. Finally, after evaluating their claims, the importance of both approaches in meta-ethics is stressed.展开更多
This paper presents a novel stiffness prediction method for periodic beam-like structures based on the two-scale equivalence at different strain states.The macroscopic fields are achieved within the framework of Timos...This paper presents a novel stiffness prediction method for periodic beam-like structures based on the two-scale equivalence at different strain states.The macroscopic fields are achieved within the framework of Timoshenko beam theory,while the microscopic fields are obtained by the newly constructed displacement form within the framework of three-dimensional(3D)elasticity theory.The new displacement form draws lessons from that in the asymptotic homogenization method(AHM),but the present field governing equations or boundary conditions for the first two order influence functions are constructed and very different from the way they were defined in the AHM.The constructed displacement form,composed of one homogenized and two warping terms,can accurately describe the deformation mode of beam-like structures.Then,with the new displacement form,the effective stiffness is achieved by the equivalence principle of macro-and microscopic fields.The finite element formulations of the proposed method are presented,which are easy to implement.Numerical examples validate that the present method can well predict both diagonal and coupling stiffness of periodic composite beams.展开更多
Using density functional theory （DFT） calculations, we rationally designed metallic nanocatalysts with ternary transition metals for oxygen reduction reactions （ORRs） in fuel cell applications. We surrounded binar...Using density functional theory （DFT） calculations, we rationally designed metallic nanocatalysts with ternary transition metals for oxygen reduction reactions （ORRs） in fuel cell applications. We surrounded binary core-shell nanoparticles with a Pt skin layer. To overcome surface segregation of the core 3-d transition metal, we identified the binary alloy Cu0.76Ni0.24 as having strongly attractive atomic interactions by computationally screening 158 different alloy configurations using energy convex hull theory. The PtskinCu0.76Ni0.24 nanoparticle showed better electrochemical stability than pure Pt nanoparticles -3 nm in size. We propose that the underlying mechanism originates from favorable compressive strain on Pt for ORR catalysis and atomic interactions among the nanoparticle shells for electrochemical stability. Our results will contribute to accurate identification and innovative design of promising nanomaterials for renewable energy systems.展开更多
文摘Moral generalism and particularism are two positions in meta-ethics which have different views regarding the relation between moral thought and principles. By accepting this relationship, generalists emphasize the necessity of principles in decision making process, and claim that the rationality of moral thought depends on the provision of a suitable supply ofmoral principles. In contrast, particularists have rejected, or at least doubted, the existence of moral principles, and believe that the rationality of moral thought depends on recognizing special features of a case and relevant conditions. This is why, unlike generalists, they use case study method rather than syllogism in decision making process and moral judgment. Consequently, to support their view, particularists commonly resort to holism in the theory of reasons, while atomism is in support of generalism. To evaluate these two attitudes, this study surveys some arguments that particularists and generalists proposed to justify their view and criticize the rival＇s one, and also explains their positions concerning the epistemological and metaphysical role of moral principles and reasons. Finally, after evaluating their claims, the importance of both approaches in meta-ethics is stressed.
基金supported by the China Postdoctoral Science Foundation(Grant No.2021T140040)the National Natural Science Foundation of China(Grant Nos.12002019 and 11872090).
文摘This paper presents a novel stiffness prediction method for periodic beam-like structures based on the two-scale equivalence at different strain states.The macroscopic fields are achieved within the framework of Timoshenko beam theory,while the microscopic fields are obtained by the newly constructed displacement form within the framework of three-dimensional(3D)elasticity theory.The new displacement form draws lessons from that in the asymptotic homogenization method(AHM),but the present field governing equations or boundary conditions for the first two order influence functions are constructed and very different from the way they were defined in the AHM.The constructed displacement form,composed of one homogenized and two warping terms,can accurately describe the deformation mode of beam-like structures.Then,with the new displacement form,the effective stiffness is achieved by the equivalence principle of macro-and microscopic fields.The finite element formulations of the proposed method are presented,which are easy to implement.Numerical examples validate that the present method can well predict both diagonal and coupling stiffness of periodic composite beams.
文摘Using density functional theory （DFT） calculations, we rationally designed metallic nanocatalysts with ternary transition metals for oxygen reduction reactions （ORRs） in fuel cell applications. We surrounded binary core-shell nanoparticles with a Pt skin layer. To overcome surface segregation of the core 3-d transition metal, we identified the binary alloy Cu0.76Ni0.24 as having strongly attractive atomic interactions by computationally screening 158 different alloy configurations using energy convex hull theory. The PtskinCu0.76Ni0.24 nanoparticle showed better electrochemical stability than pure Pt nanoparticles -3 nm in size. We propose that the underlying mechanism originates from favorable compressive strain on Pt for ORR catalysis and atomic interactions among the nanoparticle shells for electrochemical stability. Our results will contribute to accurate identification and innovative design of promising nanomaterials for renewable energy systems.
