Stress generation in thermally grown oxide films

A three dimensional finite element analysis was conducted, using the ANSYS computer program, of the stress state in a thin oxide film thermally formed on a rectangular piece of NiCrAl alloy. The analytical results indicate a very high compressive stress in the lateral directions of the film (approximately 6200 MPa), and tensile stresses in the metal substrate that ranged from essentially zero to about 55 MPa. It was found further that the intensity of the analytically determined average stresses could be approximated reasonably well by the modification of an equation developed previously by Oxx for stresses induced into bodies by thermal gradients

Religious Education in South Australian Public Schools

In 1972 the Education Act of South Australia was revised so as to make compulsory the teaching of religion in public schools. The major church leaders in South Australia held pro-Christian views about the form the new religious education should assume. Certain factors, most obviously a vigorous humanist campaign conducted during 1974 and 1975, wrought a dramatically different religious education syllabus. Convinced that the Christian religion was not being accorded its proper place, the church leaders finally lodged a united complaint with the Education Department of South Australia in 1979. The problem confronting all concerned South Australian Christians in 1982 is this: what should be the Christians\u27 attitude towards the current public school religious education program and what action, if any, should they take

The Effect of Ion Implanting on Hydrogen Entry into Metals

The effectiveness of platinum ion implanting in mitigating hydrogen entry into 4340 steel is measured and quantified. Data are presented to compare the extent of hydrogen absorption by the substrate during electrolytic hydrogen charging of platinum ion-implanted and unimplanted 4340 steel substrates. Several implanting conditions were used in processing the samples, and the surface-limited mass-transfer coefficient was calculated for each case and used to quantify the effectiveness of each treatment in reducing hydrogen absorption. It is shown that the underlying mechanism for reducing hydrogen absorption by platinum ion-implanted substrates is the catalytic effect of platinum that favors hydrogen evolution at the steel\u27s surface over hydrogen absorption by the metal. Although scattering experiments with low energy helium ions suggest that the platinum content in the first monolayer of platinum-implanted steels is small, the ability of Pt to catalyze the hydrogen evolution reaction is still strong enough to significantly reduce the quantity of hydrogen that enters the metal

Changing Needs of Individuals with Disabilities in the Time of COVID-19 as Observed by a Family Navigation Program in Miami, FL

The Family Navigator Program (FNP) is designed to help families navigate the complex system of services available to people with intellectual and developmental disabilities (I/DD), chronic health conditions, mental health issues, and other special health care needs. Based at the Mailman Center for Child Development at the University of Miami, the FNP is free and available to all families in South Florida. Most families enrolled in the FNP are receiving medical services from a university clinic; however, the program also accepts referrals from outside agencies and self-referrals. The aim of this study was to investigate the needs of families enrolled in the FNP before and after March 2020, when stay-at-home orders were put in place to address the COVID-19 pandemic. One hundred forty-five families enrolled in the FNP between November 2019 and mid-March 2020 were selected as a pre-COVID sample to be compared with 197 families enrolled from mid-March to September 2020. Families were deidentified, and data on demographics and specific needs were extracted. Demographics included race and ethnicity, language, age group, zip code, and disability or medical condition. Specific needs were defined as (1) topics on which families required education and (2) resources to which families were referred. There were no statistically significant differences in demographics before and after March 2020. There was a significant increase in referrals to financial resources during COVID (OR= 3.019, 95% CI [1.445-6.308]). There were also significant changes in the number of families provided with education on the following: increases in federal and state programs (OR = 2.156, 95% CI [1.306-3.560]) and other miscellaneous topics (1.902, 95% CI [1.081-3.348]); and decreases in school systems (OR=0.531 CI, 95% [0.328-0.858]) and therapies (CI, 95% [0.345-0.825]). These differences likely reflect the economic and social toll that the pandemic has taken on families caring for individuals with IDD and special health care needs in South Florida. Families’ priorities shifted from school and therapy to economic needs. The FNP adjusted by administering services by telephone or online, rather than by in-person meetings. These data provide a snapshot of how the needs of families changed during COVID-19 in one diverse, urban community

The effects of cold working on sensitization and intergranular corrosion behavior of AISI 304 stainless steel

The effects of prior cold rolling of up to an 80 pct reduction in thickness on the sensitization-desensitization behavior of Type AISI 304 stainless steel and its susceptibility to intergranular corrosion have been studied by electrochemical potentiokinetic reactivation (EPR) and Strauss-test methods. The results indicate that the prior deformation accelerated the sensitization as compared to the undeformed stainless steel. The deformed Type 304 stainless steel experienced desensitization at higher temperatures and times, and it was found to be enhanced by increased cold deformation. This could be attributed to the increased long-range chromium diffusion, possibly brought on by increasing pipe diffusion and vacancies. The role of the deformation-induced martensite (DIM) and texture, introduced by uniaxial cold rolling, on the sensitization-desensitization kinetics has also been discussed. This study could not reveal any systematic relationship between texture and the degree of sensitization (DOS) obtained. The effect of DIM on DOS seems to be pronounced at 500 °C when the steel retained significant amounts of DIM; however, the retained DIM is insignificant at higher sensitization times and temperatures

Hydrogen adsorption at dislocations and cracks in Fe

Solute adsorption to dislocations and cracks is considered in both the Boltzmann and Fermi-Dirac models. Explicit sums are developed for the integral amount of solute adsorbed in the defect fields. Examples of the use of the method are presented for the case of hydrogen in iron and compared with earlier results. The similarity of the condensed atmosphere of hydrogen to hydride precipitation is noted and its relevancy to hydrogen embrittlement models is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22483/1/0000024.pd