A Brief Analysis of Energy Conservation Ways by Building Materials for Ecological Architecture

The development of society and economy in China is bringing growth to all industries. In particular, the development of China’s building industry has attracted much attention. Building materials are an important part of and widely used in the building industry. Energy conservation by building materials has become an inevitable way of sustainable development. Centering on the building industry, this paper mainly discusses in detail the energy conservation ways by ecological architecture and building materials.

Thermodynamic and rate variational formulation of models for inhomogeneous gradient materials with microstructure and application to phase field modeling

In this work,thermodynamic models for the energetics and kinetics of inhomogeneous gradient materials with microstructure are formulated in the context of continuum thermodynamics and material theory.For simplicity,attention is restricted to isothermal conditions.The materials of interest here are characterized by（1） first- and secondorder gradients of the deformation field and（2） a kinematic microstructure field and its gradient（e.g.,in the sense of director,micromorphic or Cosserat microstructure）.Material inhomogeneity takes the form of multiple phases and chemical constituents,modeled here with the help of corresponding phase fields.Invariance requirements together with the dissipation principle result in the reduced model field and constitutive relations.Special cases of these include the wellknown Cahn-Hilliard and Ginzburg-Landau relations.In the last part of the work,initial boundary value problems for this class of materials are formulated with the help of rate variational methods.

Restoring ancient civilizations with “Herit-Materials”:Technological advances in its studies

Cultural relics are man-made objects left from ancient times,with historical,artistic,and scientific values.Multi-interdisciplinary research of cultural relics would enable people to obtain a variety of information associated with them,from which the restoration of ancient civilization was possible.Due to natural weathering,many cultural relics are in a fragile state,and conservation treatments that can prolong their lifetime are important,which may involve the use of conservation materials.In this paper,we define the new term “Herit-Materials” as two types of materials,including ancient cultural relics themselves and novel functional materials for conservation purposes.For the first type of Herit-Materials-cultural relics themselves,as one type of ancient materials,the concept of the relationship between the structure,composition,performance,and technology of them was introduced.The research paradigm for ancient cultural relics is also proposed.Following such a paradigm,the way how analysis and research were performed on ancient cultural relics are illustrated in detail with examples of ancient ceramics and textile dyes.Meanwhile,as the second type of Herit-Materials,three categories of conservation materials,such as emergent conservation materials on archaeological sites,consolidation materials,and cleaning materials were reviewed in detail,including basic concepts,criteria for choosing appropriate materials for conservation purposes,evaluation of the conservation effects after application,along with the application methods of those conservation materials.Finally,as Herit-Materials’ studies have attracted more and more researchers and have also created new inter-disciplinary research fields,the following research directions are recommended for scholars who have an interest,including the development of the advanced and comprehensive analytical technique of Herit-Materials,non-destructive and in-situ characterization & testing of Herit-Materials,the database of composition-structure-performance for Herit-Materials and their real-time environmental conditions,the green Herit-Materials for conservation purposes and their application methods,as well as the type and pattern analysis research of Herit-Materials.

Coupled Dynamic Modeling of Rolls Model and Metal Model for Four High Mill Based on Strip Crown Control

The crown is a key quality index of strip and plate, the rolling mill system is a complex nonlinear system, the strip qualities are directly affected by the dynamic characteristics of the rolling mil. At present, the studies about the dynamic modeling of the rolling mill system mainly focus on the dynamic simulation for the strip thickness control system, the dynamic characteristics of the strip along the width direction and that of the rolls along axial direction are not considered. In order to study the dynamic changes of strip crown in the roiling process, the dynamic simulation model based on strip crown control is established. The work roll and backup roll are considered as elastic continuous bodies and the work roll and backup roll are joined by a Winkler elastic layer. The rolls are considered as double freely supported beams. The change rate of roll gap is taken into consideration in the metal deformation, based on the principle of dynamic conservation of material flow, the two dimensional dynamic model of metal is established. The model of metal deformation provides exciting force for the rolls dynamic model, and the roils dynamic model and metal deformation model couple together. Then, based on the two models, the dynamic model of rolling mill system based on strip crown control is established. The Newmark-13 method is used to solve the problem, and the dynamic changes of these parameters are obtained as follows： （1） The bending of work roll and backup roll changes with time; （2） The strip crown changes with time; （3） The distribution of rolling force changes with time. Take some cold tandem rolling mill as subject investigated, simulation results and the comparisons with experimental results show that the dynamic model built is rational and correct. The proposed research provides effective theory for optimization of device and technological parameters and development of new technology, plays an important role to improve the strip control precision and strip shape quality.