Compatibility of Materials with Cryogens

1983 ◽  
pp. 343-369
Author(s):  
J. C. Moulder ◽  
J. G. Hust
Keyword(s):  
Low Temperature ◽  
Liquid Oxygen ◽  
Hydrogen Environment ◽  
Physical Interactions ◽  
The Common ◽  
Materials Used ◽  
Hydrogen Systems ◽  
Compatibility Of Materials

Abstract This chapter discusses the compatibility problems that arise from chemical or physical interactions between liquefied gases and the common materials used in their production, storage, transportation, distribution, and use. The discussion covers the compatibility of materials with liquid oxygen and liquid fluorine. Hydrogen-environment embrittlement is unique to low-temperature hydrogen systems and is also discussed.

Molecule-Based Magnets—An Overview

MRS Bulletin ◽  
2000 ◽  
Vol 25 (11) ◽  
pp. 21-30 ◽  
Author(s):  
Joel S. Miller ◽  
Arthur J. Epstein
Keyword(s):  
Low Temperature ◽  
Vapor Deposition ◽  
Room Temperature ◽  
Chemical Vapor ◽  
Magnetic Ordering ◽  
Low Density ◽  
Materials Properties ◽  
The Common ◽  
New Processing ◽  
Very High

Molecule-based magnets are a broad, emerging class of magnetic materials that expand the materials properties typically associated with magnets to include low density, transparency, electrical insulation, and low-temperature fabrication, as well as combine magnetic ordering with other properties such as photoresponsiveness. Essentially all of the common magnetic phenomena associated with conventional transition-metal and rare-earth-based magnets can be found in molecule-based magnets. Although discovered less than two decades ago, magnets with ordering temperatures exceeding room temperature, very high (∼27.0 kOe or 2.16 MA/m) and very low (several Oe or less) coercivities, and substantial remanent and saturation magnetizations have been achieved. In addition, exotic phenomena including photoresponsiveness have been reported. The advent of molecule-based magnets offers new processing opportunities. For example, thin-film magnets can be prepared by means of low-temperature chemical vapor deposition and electrodeposition methods.

THE OCCURRENCE OF BUILDING DEFECTS DURING DEFECT LIABILITY PERIOD (DLP)

2015 ◽  
Vol 75 (5) ◽  
Author(s):  
N. H. Che Hasim ◽  
A. Akhavan Tabassi
Keyword(s):  
Construction Industry ◽  
Developing Country ◽  
New Economy ◽  
Quality Of Work ◽  
The Future ◽  
The Common ◽  
Materials Used

Malaysia is a developing country with various projects and it can generate new economy and can also provide benefit to firms and protection to the residents. However, there are some firms have acted unprofessionally by not using the correct specification. Therefore, there have been many complaints about defects on the home purchased, in terms of quality of work and materials used. Defects liability period (DLP) is a term that the contractor is obliged to remedy the defects occurs in this period. The research presented in this paper aims to broaden previous research on defects by analyzing the defects during DLP, which usually lasts 12 months after the handover period, and aimed to identify the common contribution cause of defects to buildings. The data were obtained from site observation and questionnaire from various players in the construction industry of Malaysia. The finding of this study can be used for future references andcan improve the effectiveness of managing defects in the future of the industry.

Electroluminescence from GalnN Quantum Wells Grown on Non-(0001) Facets of Selectively Grown GaN Stripes

2004 ◽  
Vol 831 ◽  
Author(s):  
Barbara Neubert ◽  
Frank Habel ◽  
Peter Bruckner ◽  
Ferdinand Scholz ◽  
Till Riemann ◽  
...  
Keyword(s):  
Low Temperature ◽  
Electric Field ◽  
Quantum Wells ◽  
Room Temperature ◽  
Light Emission ◽  
Low Pressure ◽  
Lower Efficiency ◽  
Strong Light ◽  
The Common ◽  
Piezo Electric

ABSTRACTNon (0001) GalnN QWs have been grown by low pressure MOVPE on side facets of triangular shaped selectively grown GaN stripes. By analysing low temperature photo- and cathodoluminescence and room temperature electroluminescence, we found strong indications, that both, In and Mg are less efficiently incorporated on these side facets compared to the common (0001) plane with even lower efficiency for stripes running along (1–100) compared to (11–20). Nevertheless, we observed strong light emission from these quantum wells, supposed to be at least partly caused by the reduced piezo-electric field.

scholarly journals Porous Carbon Materials for Elements in Low-Temperature Fuel Cells

2015 ◽  
Vol 60 (1) ◽  
pp. 117-120 ◽  
Author(s):  
R. Wlodarczyk
Keyword(s):  
Fuel Cells ◽  
Low Temperature ◽  
Carbon Materials ◽  
Operating Conditions ◽  
Hydrogen Fuel Cells ◽  
Hydrogen Fuel ◽  
Commercial Carbon ◽  
Synthetic Solution ◽  
Low Temperature Fuel Cells ◽  
Materials Used

Abstract The porosity, distribution of pores, shape of pores and specific surface area of carbon materials were investigated. The study of sintered graphite and commercial carbon materials used in low-temperature fuel cells (Graphite Grade FU, Toray Teflon Treated) was compared. The study covered measurements of density, microstructural examinations and wettability (contact angle) of carbon materials. The main criterion adopted for choosing a particular material for components of fuel cells is their corrosion resistance under operating conditions of hydrogen fuel cells. In order to determine resistance to corrosion in the environment of operation of fuel cells, potentiokinetic curves were registered for synthetic solution 0.1M H2SO4+ 2 ppmF-at 80°C.

Orientation Studies of α-Al(Fe,Mn)Si Dispersoids in 3xxx Al Alloys

2014 ◽  
Vol 794-796 ◽  
pp. 39-44 ◽  
Author(s):  
Astrid Marie Flattum Muggerud ◽  
Yan Jun Li ◽  
Randi Holmestad
Keyword(s):  
Mechanical Properties ◽  
Low Temperature ◽  
Orientation Relationship ◽  
Aluminum Matrix ◽  
Al Alloys ◽  
Orientation Relationships ◽  
The Matrix ◽  
The Common ◽  
Habit Planes ◽  
Al Matrix

Dispersoids are important in 3xxx Al alloys, influencing mechanical properties, texture and recrystallization. In this work α-Al (Fe,Mn)Si dispersoids have been studied after low temperature homogenisation. The common orientation relationship between dispersoids and Al matrix has been reported in earlier studies. Here a systematic study on the orientation relationship and its exceptions is presented. It is found that most of the dispersoids follow the common orientation relationship, [1-1 1] α //[1-1 1]Al , (5-2 -7 ) α //(0 1 1)Al . Here the dispersoids are semi coherent with the Aluminum matrix. Different morphologies and habit planes are possible. Deviations from the most commonly observed orientation relationships are presented and discussed, to underline the complexity of the phase and its relation to the matrix.

Uniform Low-Temperature Deposition of Optical Layers by Plasma-Activated CVD

1992 ◽  
Vol 269 ◽  
Author(s):  
Hans Lydtin ◽  
Arnd Ritz
Keyword(s):  
Low Temperature ◽  
Layer Thickness ◽  
Operation Mode ◽  
Plasma Source ◽  
Multilayer Structures ◽  
Dielectric Layers ◽  
Remote Operation ◽  
Temperature Deposition ◽  
Microwave Applicator ◽  
Materials Used

ABSTRACTPlasma activated CVD in a remote operation mode is applied to the deposition of dielectric layers on extended substrates. Layer thickness uniformity of ±1% over areas of 80mm diameter is demonstrated. The microwave applicator sustaining the plasma source of condensable species is compared in its deposition characteristic to conventional evaporation sources. Deposition efficiencies up to 70% are reached. The layer materials used are SiO2 and TiO2. Multilayer structures are prepared and optically characterized.

Ash Fusibility Based on Modes of Occurrence and High-Temperature Behaviors of Mineral Matter in Coals

2016 ◽  
Vol 139 (2) ◽  
Author(s):  
Xinye Cheng ◽  
Kexin Han ◽  
Zhenyu Huang ◽  
Zhihua Wang
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Melting Process ◽  
Mineral Matter ◽  
Slight Reduction ◽  
Modes Of Occurrence ◽  
Ash Melting ◽  
Ash Fusibility ◽  
Three Stages ◽  
The Common

Complete quantitative data of the chemical (proximate, ultimate, and ash analyses) and mineral (in low-temperature ash (LTA) and various high-temperature ashes (HTA)) compositions of 21 coals were used to investigate the modes of occurrences and high-temperature behaviors of the minerals in coals and their influence on ash fusibility. The common minerals present in the low-temperature ashes (LTA) are kaolinite, quartz, muscovite, calcite, gypsum, pyrite, and siderite. The samples were divided into two groups according to the hemispherical temperature for a comparative study of the behavior of mineral matters. Results show that the average number of mineral species (ANMS) and amorphous substances (AS) in the LTAs of the two groups are essentially the same. The ANMS in both the low and high (ash fusion temperatures, AFT) ash samples go through the same tendency of a slight reduction at first, an increase, and finally, a significant reduction. As the temperature increases, the ANMS in the low-AFT ash is initially higher and then lower than the high-AFT ash, whereas the tendency of the AS is quite the opposite. The ash melting process is divided into three stages, and the AFTs are related to different degrees of the eutectic stage.

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