BASIC PROPERTIES OF CARBONATION-TREATED CAO-BASED EXPANSIVE MATERIAL

Economic loss due to egg shell breakage is an important problem in intensive egg production systems (Oosterwoud, 1987). Eggs are subjected to mechanical impacts at the moment of lay, during collection, in the sorting equipment and during transport in trays. Bain (1991) reported that 6% to 8% of all eggs laid are broken during handling from the production unit to the consumer, and in monetary terms this gives rise to losses of at least $600 million on a world wide basis. The value of egg production was $3.389 billion in 1992, compared to $ 3.209 billion in 1987 (Madison and Perez, 1994). Therefore, egg shell breakage continues to be a costly problem for the egg industry. In addition, people are at high risk when eating eggs which might be contaminated after being damaged, i.e., with cracks or checks (Amer, 1998; Bain, 1990). Egg shell breakage depends both on the strength of the egg shell and magnitude of the mechanical load applied. Variables associated with shell strength are biological in nature (Hamilton, 1982). They involve the material and structural properties of the different layers which comprise the egg shell. The material properties depend on the type and the association between the mineral and organic components of the shell. The structural properties depend on egg shell thickness, size and shape of the egg and the distribution of shell over the egg surface. In most of the methods used for measuring egg shell strength these basic physical properties are not quantified separately because of their complexity. Indeed, the shell curvature and its brittle nature make it difficult to measure the material properties of the shell by classical means (Amer Eissa & Gamea, 2003; Bain, 1990). Therefore, more practical techniques have to be developed. Such methods, however, describe the behaviour in terms of a superposition of several material and structural properties of the egg. One such commonly used method is the non-destructive, quasi static compression test. In this test the elastic stiffness properties of the whole egg shell structure are measured. An egg is placed horizontally between 2 flat parallel steel plates and then compressed at a constant compression speed until a predefined

Major payoffs of new aerospace structures in terms of weight savings, performance, and life-cycle cost are anticipated from successful development of advanced materials. To aid in development of new alloy systems a method has been developed for predicting weight savings resulting from material (property set) improvements for specific failure modes in aircraft structures. Material properties include density, modulus of elasticity, strength, fatigue, crack growth, fracture toughness, and stress corrosion resistance. Weight savings analysis includes consideration of the margins of safety for various failure modes that could affect the size of the aircraft structure. Results of analysis applicable to a carrier-based patrol aircraft and an advanced tactical fighter indicate a weight savings potential of up to 16 percent for advanced aluminum alloys.

Integrity assessment of girth welds in in-service vintage pipelines is sometimes necessary, including regulatory requirements, changes in service or pipe support conditions which may cause additional stress on the girth welds, or “indications” being reported in in-line inspection (ILI). Material properties and flaw characteristics are essential in such assessment, but very little data are available in most cases. In a PRCI-funded effort, material properties and flaw characteristics of vintage girth welds are generated and analyzed to fill the critical gaps. The output of this effort is being used as the inputs to a vintage girth weld assessment procedure being developed in a separate and parallel effort. The outcome of these efforts collectively allows for the assessment of vintage girth welds, which is a part of an overall integrity management program. The basic material property data being generated include (i) pipe tensile properties in both hoop and longitudinal directions, (ii) weld metal tensile properties, (iii) macrohardness traverse, and (iv) Charpy impact transition curves with notches in the heat affected zone (HAZ) and deposited weld metal. These data provide essential information on tensile strength, weld strength mismatch, and toughness. In addition, tensile tests were conducted on cross-weld specimens with natural flaws and artificially machined planar flaws. These cross-weld tests provide an indication of the welds’ stress capacity in the presence of flaws. They also provide the apparent toughness which is essential in assessing welds’ tensile strain capacity. All tested girth welds were inspected using radiography and phased array UT. Thus, this work provides a coherent picture of the material properties, flaw characteristics, and stress and strain capacities of the tested vintage girth welds.

This study aimed to determine the effect of variations in material properties of the intervertebral disc on dynamic response of the human lumbar spine to vertical vibration using a finite element model of the lumbar L1-S1 motion segment. The present material sensitivity study was conducted by varying elastic moduli for annulus ground substance (AGS), annulus fibers (AF), and nucleus pulposus (NP) in the disc. Transient dynamic analysis was performed initially on the model with basic material property under a sinusoidal vertical vibration load. Subsequently, the same analysis was done for each of the three disc components corresponding to high and low material property cases. The computed results were plotted as a function of time and compared. The AGS property displayed a larger impact on vertebral axial displacement and von Mises stress in AGS, and the AF property displayed a larger impact on disc bulge. In contrast, the NP property had little effect on all the response parameters. Additionally, the intradiscal pressure was found to be not sensitive to any of the disc properties. These findings may be helpful in adoption of appropriate material parameters for the intervertebral disc in finite element model of the lumbar spine used for vibration analysis. Graphical abstract Material property sensitivity analysis on vibration characteristics of the human lumbar spine.

As environmental pollution worsens, related environmental regulations are becoming stricter. Recently, regulations on internal combustion engine vehicles have been tightening, leading to increased attention towards hydrogen and electric vehicles as alternatives. Especially within a decade, electric vehicles have emerged as prominent eco-friendly vehicles, with lithium-ion batteries garnering significant attention as energy storage devices. Among them, all solid-state batteries, boasting advantages such as high energy density and output, are continuously researched as the ultimate solution, free from issues like explosions. The battery manufacturing process typically comprises the pole plate process, assembly process, and formation process. To enhance battery performance and manufacturing efficiency, process optimization is essential, and simulation can reduce resource and time wastage.Finite Element Method (FEM) is a prominent simulation technique that can simulate various processes to derive optimal designs or processes. Predicting problems that may occur during electrode manufacturing processes and deriving relevant alternatives can save time and costs.Accurate simulation requires high-quality mechanical properties of materials. However, for sulfide-based solid electrolytes, exposure to air leads to material property changes, and their thickness, often below 100μm, makes deriving material properties through measurement nearly impossible.To estimate electrode material properties, Xu derived force-deformation curves (F-D Curve) through measurements for the entire lithium-ion battery (LIB) and calculated the material properties of the anode-separator-cathode assembly as representative properties. Wierzbicki estimated the mechanical properties of cylindrical-shaped lithium-ion cells using homogenization techniques. However, in such cases, it is impossible to obtain data for each component, resulting in weaknesses in optimizing the process for all solid-state batteries.To obtain data for each component, Cheng measured the elastic modulus using nanoindentation after sintering the NMC powder to derive the material properties of NMC, a key cathode material. However, for sulfide-based batteries, such as those using solid electrolytes, approaching through the above methods is impossible due to their reaction with air.In this study, we utilized Crystal Graph Convolutional Neural Network (CGCNN), a machine learning technique, to derive the material properties of Li6PS5Cl, a representative material among sulfide-based solid electrolytes. Materials are composed of a crystal structure where atoms are arranged in a certain pattern. Due to variables such as the type of atoms, composition ratio, and arrangement, predicting outcomes is challenging without measurements. However, CGCNN inputs structural information of bulk materials to predict basic properties accurately, offering a promising alternative. After modeling the material structure, a certain strain was applied to calculate the bulk modulus and shear modulus. Using this data, CGCNN was trained to predict micro-scale bulk modulus and shear modulus, from which Young’s modulus and Poisson’s ratio, representing key mechanical properties, were derived.Based on this study, utilizing CGCNN, the material properties of Li5PS5Cl were predicted, resulting in Young’s modulus of 28.07 MPa, Shear Modulus of 11.02 MPa, and Poisson’s ratio of 0.27. This study successfully derived the challenging-to-measure material properties of solid-state batteries. This serves as fundamental data for process optimization in the mass production process of solid-state batteries, contributing to enhanced productivity and cost reduction. This research is expected to significantly contribute to the ultimate goal of optimizing the manufacturing process of solid-state batteries and improving productivity, ultimately leading to cost reduction.This work was supported by Technology Innovation Program (project name : Equipment technologies for 50cm2 all solid state battery cell, project Number : 20012349) funded by the Ministry of Trade, Industry & Energy (MOTIE, Korea).This research has been conducted with the support of the Ministry of Trade, Industry and Energy(MOTIE), Republic of Korea as “Development of a battery pack case for electric vehicles that deltas thermal runaway”(P0024522) in the small and medium business win-win innovation leap project.This research was funded by the ‘New Faculty Research Support Grant’ at Changwon National University in 2024.

The UV community for the fourth time took part in the International Workshop on Ultraviolet Materials and Devices (IWUMD4), which was organized in September 2019 by the Ioffe Institute, St. Petersburg, Russia. This event, following the successful meetings in Beijing, China (2016), Fukuoka, Japan (2017), Kunming, China (2018), was intended to show new horizons beyond the UV-blue LEDs based on wide-bandgap III-Nitrides. Material science, modeling and technology for the “UV gap” (200-300 nm) are at the frontier of applied physics. The studies are aimed at developing devices for such areas as medicine – for human-safely disinfection and rapid detection of viral threats, communication – for noise-protected and solar- blind UV-optical communication, nanotechnology – for high- resolution photolithography and for many other applications in the field of biology, pharmaceuticals and forensics.The Workshop was attended by 125 scientists from 15 coun- tries, including half from Asia and half from Europe and theDOI: 10.1002/pssa.202000378USA. The Program was very eventful and included 2 plenary talks by Prof. Chris G. Van de Walle (UCSB) and Prof. Michael Kneissl (TU Berlin&FBH), 4 keynotes, and 25 invited papers, as well as 35 oral presentations and 36 poster contributions displayed during two poster sessions. Prior to Workshop, the Tutorials on the basic properties of wide-gap semiconductor materials and nanostructures with lectures of outstanding experts in this field were held for one and a half days. The scope of the presentations at the Workshop was quite wide. Besides the fundamental properties of wide-gap semiconductor materials and nanostructures, their optical and structural characterization and applications, it highlighted new trends, such as the growth, basic properties and applications of Ga2O3 and physics of BN from bulk to 2D materials.This issue features selected reports from the Workshop participants. Recent results on the manufacture of high-quality templates of the nitrides and oxides by using differenttechnological approaches are presented. The fundamental problems of low-dimensional heterostructures and the techno- logical challenges of various epitaxial growth methods, such as molecular beam epitaxy and metalorganic chemical vapor deposition, are examined in detail to further improve the quan- tum efficiency and output power of UV light-emitting devices. A study of the optical properties of AlGaN layers and laser diode heterostructures are presented, which elucidate the nature and characteristics of spontaneous and stimulated emis- sions in AlGaN laser structures. In addition, the fabrication and radiation of GaN hexagonal microcavities are discussed. A variety of topics reflects the wide range of interests of the Workshop.The Editors would like to thank all the members of the International Advisory and Program Committees for their encouragement and great help during the Workshoporganization. We are grateful to the referees for their efforts and time devoted to the paper review process. We owe our best thanks to the official partners and sponsors of the workshop, as well as all participants at the symposium exhibition. Finally, we would like to express our sincere gratitude to Dr. Stefan Hildebrandt and the production team of physica status solidi for their friendly assistance and collaboration in the editorial process.The next 5th International Workshop on Ultraviolet Materials and Devices (IWUMD5) is planned to be held in November 2020 in Jeju, Korea. We wish the organizers a gorgeous and successful meeting.

Recent progress of preparation of branched poly(lactic acid) and its application in the modification of polylactic acid materials

The elements of railway turnouts made from rail sections of R260 high carbon steel must have a high resistance to abrasive and contact fatigue wear, as well as a good resistance to cracking under service loads. These mechanical properties largely determine the suitability of steel for use as railway track components. In this study, two groups of specimens were subjected to tests of mechanical properties and metallurgical analyses. The first group included material obtained from the hot-rolled block section, the rolling end temperature being Tkw = 950°C, while the second group was material after the rolling process with the subsequent 20-minute isothermal annealing at a temperature of 480°C. The microstructure of tested materials (Rm, Rp0.2, A5, Z, HB) was characterized, and their basic mechanical properties and fracture toughness in the KIc plane strain condition were determined. Also the effect of temperature, ranging from-80°C to 100°C, on the KCU impact toughness of R260 steel was established. Based on the SEM observation using the Hitachi S-3400N scanning microscope, it was found that pearlitic structure with a varied distance between cementite plates, equal to 0.29 μm and 0.09 μm, respectively, appears in the hot-rolled R260 steel and in the steel subjected to additional isothermal annealing treatment. The impact of pearlite morphology on the cracking characteristics and basic mechanical properties of materials was analyzed. It was found that at room temperature, the higher fracture toughness (KIc = 66.4 MPa·m1/2) is shown by the steel after isothermal annealing at 480°C, in which less distance between the plates of cementite has been observed in the perlite. The fracture toughness of R260 steel after hot rolling at 950°C was KIc = 48.3 MPa·m1/2. As in the case of fracture toughness, the impact strength of R260 steel after isothermal annealing was significantly greater than the impact strength of steel only after hot rolling. The determined cracking characteristics of R260 steel make it possible to determine the effect of heat treatment on the formation of microstructure and material properties, which determine the service life of rail sections.

Fibre cements and fibre concretes: D.J. Hannant John Wiley, New York, 219 pp., ISBN 0 471 99620 3 £11.50 (1978)

This section is an introduction into materials that can be used as Phase Change Materials (PCM) for heat and cold storage and their basic properties. At the beginning, the basic thermodynamics of the use of PCM and general physical and technical requirements on perspective materials are presented. Following that, the most important classes of materials that have been investigated and typical examples of materials to be used as PCM are discussed. These materials usually do not fulfill all requirements. Therefore, solution strategies and ways to improve certain material properties have been developed. The section closes with an up to date market review of commercial PCM, PCM composites and encapsulation methods.

Comparison between fatigue behavior of some ceramics: a new concept of intrinsic stress-corrosion exponent n0

Time-domain electric circuit simulation packages designed for power systems ffiXS r° *2 ** *? ™*'y ***<* ^works provided the track and traction line impedance and admittance are known from basic track geometry and material properties. This paper illustrates the use of the EMTP whh^n ^ ?™** ™^ ^ obtain the track impedance and capacitance with special reference to running rail circuits. By comparison with practical measurements it ,s shown that with care, the method is suitable for track impedance, but less precise for running rail circuit capacitance.

The geotechnical properties of the fine‐grained sediments of the Tiber River prodelta slope are described. Laboratory investigations depict the overall physical and mechanical behavior of the sediments and give information regarding their in‐situ conditions due to gravitational campaction. In spite of relative homogeneity in terms of the basic geotechnical properties, noticeable differences between materials sampled at different water depths and at different depths below the seafloor can be detected. This variation is observed when in‐situ material properties are taken into account and can be explained if the different depositional and burial conditions of the sediments are considered. In particular, differences in compressibility and undrained behavior have been found between sediments sampled immediately underneath the seafloor and the underlying materials as well as between the entire present‐day prodelta clays and the “aged”; sediments of the delta front, which were originally deposited in a prodelta slope environment. These considerations can be generalized to other small marine deltas, which are not characterized by the exceptional depositional rates typical of the extensively studied large deltas but frequently occur worldwide and host offshore engineering activities.

Although heat‐straightening has been used for the repair of damaged steel structures for over 40 yr, the process is more of an art than a science. Since the effects of heat‐straightening steel structures are not well understood by the engineering community, a number of undocumented opinions have appeared in the literature that are false or misleading. Presented here is a state‐of‐the‐art review in the form of popular fables followed by the documented facts related to each one. Sixteen fables are listed in two categories: basic material properties and behavior of structural systems. The references cited form a comprehensive bibliography on the subject of heat‐straightening effects on steel. The selection of facts and fables has been chosen to provide the reader with an understanding of the process, important factors influencing heat‐straightening of rolled and built‐up members, a working knowledge of its effect on the material properties of steel, and the sources for additional information. Heat‐straightening has produced a good track record that illustrates the potential of the method for providing safe and economical repairs.

The material property measurements of thermal bamer coatings from cyclic fumaa, thermal rig, thermal expansion, acoustic emission and tensile adhesion test methods are critically examined. Some basic engineering properties of coatings such as the elastic modulus have not been measured without ambiguity. Data of this nature is essential to the success of modeling studies. Insights into the mechanical properties of coatings have been gained by carrying out instrumented tensile adhesion tests. The general view of the coating deformation process is that the individual lamelhe slide wer each other and this promotes a pseudoductility response in the coatings. Monitoring of the acoustic emission response of coatings during thermal cycling aperiments suggests that there are two distinct cracking processes. The macrocracking behavior, indicated by a change in the acoustic emission count rate, is the predominant mechanism which leads to coating failure. It is further shown that the acceptance tests used by industry, although useful in ranking coatings in terms of a particular property, present no fundamental knowledge concerning the material properties of coatings. It is only when the phenomenological characteristics of the thermo-mechanical response of coatings is undemtood that coating development will substantially progress.