Vacuum application of thermal barrier plasma coatings

Coatings are presently applied to Space Shuttle Main Engine (SSME) turbine blades for protection against the harsh environment realized in the engine during lift off-to-orbit. High performance nickel, chromium, aluminum, and yttrium (NiCrAlY) alloy coatings, which are applied by atmospheric plasma spraying, crack and spall off because of the severe thermal shock experienced during start-up and shut-down of the engine. Ceramic coatings of yttria stabilized zirconia (ZrO2-Y2O3) were applied initially as a thermal barrier over coating to the NiCrAlY but were removed because of even greater spalling. Utilizing a vacuum plasma spraying process, bond coatings of NiCrAlY were applied in a low pressure atmosphere of argon/helium, producing significantly improved coating-to-blade bonding. The improved coatings showed no spalling after 40 MSFC burner rig thermal shock cycles, cycling between 1700 and -423 F. The current atmospheric plasma NiCrAlY coatings spalled during 25 test cycles. Subsequently, a process was developed for applying a durable thermal barrier coating of ZrO2-Y2O3 to the turbine blades of first stage high-pressure fuel turbopumps utilizing the vacuum plasma process. The improved thermal barrier coating has successfully passed 40 burner rig thermal shock cycles without spalling. Hot firing in an SSME turbine engine is scheduled for the blades. Tooling was installed in preparation for vacuum plasma spray coating other SSME hardware, e.g., the titanium main fuel valve housing (MFVH) and the fuel turbopump nozzle/stator

A Ground-based Search for Lunar Resources Using High-resolution Imaging in the Infrared

When humans return to the Moon, lunar resources will play an important role in the successful deployment and maintenance of the lunar base. Previous studies have illustrated the abundance of resource materials available on the surface of the Moon, as well as their ready accessibility. Particularly worth considering are the lunar regional (2,000-30,000 sq km) pyroclastic deposits scattered about the lunar nearside. These 30-50-m-thick deposits are composed of fine-grained unconsolidated titanium- and iron-rich mafic glasses and may be used as bulk feedstock for the beneficiation of oxygen, iron, titanium, sulfur, and other solar wind gases, or simply used as is for construction and shielding purposes. A groundbased observing survey of the resource-rich regions on the lunar nearside using a new imaging technique designed to obtain much higher resolution images, and more precise compositional analyses than previously obtainable is proposed

The nature and implications of the part-time employment of secondary school pupils

This paper reports on the results of a review of existing measures of enterprising skills and attitudes. The review was undertaken firstly to identify definitions of enterprising skills and attitudes and secondly to inform the design of the questionnaire of school pupils and of the focused studies. It has been written by Linda Brownlow and Sheila Semple, both members of the research team. This paper is being circulated to advisory group members only at this stage [2004]

NSW Police Force and rural crime

Rural crime has a financial, emotional and physical impact on its victims, their family and the community. Often the victims are isolated, their livestock and equipment are extremely valuable and their rural properties are a family business handed down from generation to generation, with the families working hard and making large sacrifices to keep their business profitable and able to supply the greater community with quality produce. The direction of the NSW Police Force towards rural crime has evolved over the past 70 years. The renewed focus and creation of the Rural Crime Prevention Team is a significant enhancement on our ability to target rural crime within NSW. This article discusses the history of the NSW Police Force involvement in rural crime and, particularly, the approaches taken by the Rural Crime Prevention Team since December 201

The downfall of the children of night Physical and non-physical entities in fifth-century B.C. Greek thought

No Abstract

The Trucking Industry in Ontario

Le seul exemple de l'industrie ontarienne du camionnage fournit un modèle sophistiqué de négociation multi-employeur et présente un climat agité de relations du travail, climat caractérisé par des grèves sauvages.La partie syndicale représentée par les unités locales des Teamsters a fait preuve d'une cohésion d'ensemble en négociant globalement avec l'association d'employeurs et en faisant bloc dans les arrêts de travail. L'association d'employeurs de son côté négocie des conventions collectives multi-employeurs et de plus simples contrats couvrant 65 compagnies. Cette association regroupe 21,000 membres et conduit les négociations par son Conseil mixte composé de représentants des onze locaux de la province.Les employeurs trouvent plusieurs avantages à ce style de négociations. Sans tous les mentionner, notons la possibilité d'un front commun, l'auto-détermination des politiques et l'absence de concurrence dans les salaires. Pour le côté syndical, notons entre autres avantages d'un tel style de négociations : une plus grande facilité d'administration et l'uniformité dans les tactiques de grèves.L'absence de négociation au niveau de la firme et les imperfections de l'organisation au moment de crise apparaissent comme les principaux inconvénients de ce type de négociation du côté patronal. Du côté syndical, la présence d'une menace possible de lockout constitue un désavantage marqué.En Ontario, la partie patronale a fait preuve d'une remarquable stabilité principalement basée sur sa structure organisationnelle, sur la faiblesse de la partie syndicale, sur des techniques raffinées d'administration de conventions collectives et sur la solidarité des employeurs. Comme résultat, le chaos actuel résulte principalement de la dissension à l'intérieur des syndicats.In this case study of the Ontario trucking industry, the author considers the«  for hire » section of the industry and, within this section, emphasizes general freight transport in order to illustrate the advantages and shortcomings of the multi-employer bargaining system

Skills and Student Affairs: A Discourse Analysis

Media, industry, and other public actors have claimed that a ‘skills gap’ exists in students exiting post-secondary education and entering the workforce. The Ontario provincial government has developed policy, the Highly Skilled Workforce Strategy, to provide directives to universities in the province to provide skills development to students to aid in closing the gap and providing a workplace relevant education. In this study, I explore the experiences of student affairs and services (SAS) staff responsible for enacting provincial policy related to skills development at the university level by investigating the discourses that shape policy and practices of these staff in their daily work. Data collected from documents related to the issue of skills, and from interviews with SAS staff, provided insight into how the problem of skills is represented in policy and in practice. Discourses shaping the practice of SAS staff related to skills development at times conflicted the discourses shaping the issue of skills in policy, but a neoliberal economic rationality is embedded within the broader representation of the issue of skills, with discursive implications for SAS staff and for students

Problem solving in infancy : a study of infants performance on tasks of spatial manipulation

Children, 12 to 24 months of age, were presented with three tasks: two detour problems and a spatial task. The aim of the study was to assess the performance on each task and to consider the relationship between performance on the two detour problems and the relationship between spatial knowledge and detour ability. The two detour tasks (the lever task and the bent wire task) shared a common feature in that the object rather than the subject had to be moved in the detour. The results of the lever task indicated that age, experimental group (three lever designs were used) and the sex of subjects were influential variables. Analysis of the bent-wire data showed that as hypothesised age was the most important variable, accounting for qualitative and quantitative differences in performance. The results from the detour tasks were discussed with reference to the attainment of skilled behaviour and the relationship between cognitive development and detour ability. Spatial task results indicated that performance was related to age and that the type of error recorded was also related to the age of the subject. The hypothesised relationship between the two detour tasks was not supported by the data. Furthermore, the anticipated relationship between detour ability and spatial knowledge failed to emerge. These results were discussed in relation to the issue of developmental synchrony and the structuralist's view of development