The Legacy of Alois Riegl: Material Authenticity of the Monument in the Digital Age

The Austrian art historian Alois Riegl(1858-1905)revolutionised the European concept of the monu­ment and paved the way towards the codification of the historicity of artefacts at the international level.Today,conservation work and relevant terminology still build upon the principles first outlined in his work Der moderne Denkmalkultus(1903)more than a hundred years ago.And yet,modern information/communication technologies have long challenged the idea of‘age value’(Alterswert),of a monument possessing value simply because it shows‘signs of age’(Altersspuren),through their ability to digitally recreate historical architecture in its original form and thereby to transcend the boundaries of time and space.This paper discusses the challenges and opportunities for monument preservation in the 21st century in the light of Riegl’s thoughts on how to perceive(‘visualise’)the past.It investigates the validity of Riegl’s theories in the context of today’s virtual reality/ies at a theoretical level,and their potential for advancement in preservation theory,expanding on historical thoughts rooted in 18th and 19th century preservation theories.By analysing Riegl’s commemorative values,stratigraphic picturing of history’s mate­rial debris,and fear of formlessness,this paper explores digitisation as the driving force for change in attitude from traditional,restrictive thinking to a modern way of thinking which is receptive to new technological developments,including,for example,exploring augmented and virtual realities as a means of achieving the sensory aesthetic ex­perience required by age value.

Effect of trace Ti and Y on mechanical properties of Au-based alloys with 990 fineness

The effect of trace Ti and Y on Au-based alloys with 990 fineness has beeninvestigated systematically by means of tensile test, hardness test, scanning and transmissionelectron microscopic analyses. These experimental results show that trace Ti and Y can significantlyimprove the mechanical properties of Au-based alloys with 990 fineness because Ti and Y cansignificantly refine matrix grains, and solid solution strengthening, work strengthening andprecipitation strengthening occur during mechanical heat treatment.

Structure and Properties of Isotactic Polypropylene/Polybutene-1 In-reactor Alloys

The composition and structure of polymer largely determine the properties of its final products.As a novel polymer material,the composition,structure,and properties of the isotactic polypropylene/polybutene-1 in-reactor alloy(PPIPB alloy)synthesized by sequential two-stage polymerization with Ziegler-Natta catalyst were correlated for the first time in this work.The iPP/PB alloy was fractionated by temperature rising elution fractionation(TREF)in a broad temperature ranged from-30℃ to 140℃,and the chain microstructures and sequence distributions of isolated fractions were analyzed by DSC,GPC,13C-NMR,and FTIR.The iPP/IPB alloy was composed of five components,namely high isotactic PB(PB,85.8 wt96),medium isotactic PB(mPB,5.1 wt%),polyl(butene-1)-block propylene copolymers(PB-6 PP,4.1 wt%6)which contained PB and PP blocks with dfferent lengths according to the isolation temperature,isotactic PP(iPP,2.7 wt%6),and atactic PB(aPB,2.3 wt96).Compared to other commercial pipe materials,the P/iPB alloy presented outstanding thermal creep resistance and gas permeability resistance,high strength and low deformation at high temperature,and appropriate flexural strength.The roles of PP and PB-b-PP components in the alloy were interpreted.This work is expected to elucidate the potential application of PPIPB aloy as pipe materials and provide solutions for the design and synthesis of high performance pipe materials.

Antibacterial Ti-Mn-Cu alloys for biomedical applications

Titanium alloys are common biomedical materials due to their biocompatibility and mechanical performance.However,titanium alloys are expensive and,unless surface treated,generally cannot prevent surgical infections related to bacteria which can damage the integrity of the implant.In this study,new titanium alloys were developed via powder metallurgy and the addition of manganese and copper,respectively,aiming to limit the manufacturing costs and induce new functionality on the materials including antibacterial response.The addition of manganese and copper to titanium significantly changes the behaviour of the Ti-Mn-Cu alloys leading to the successful stabilization of the beta titanium phase,great refinement of the typical lamellar structure,and achievement of materials with low level of porosity.Consequently,it is found that the mechanical performance and the antibacterial efficacy are enhanced by the addition of a higher amount of alloying elements.The manufactured Ti-Mn-Cu alloys fulfil the requirements for structural biomedical implants and have antibacterial response making them potential candidates for permanent medical implants.