1,404 research outputs found
Generation of Generalized-Gauss Laser Beams via a Spatial Light Modulator
Generalized-Gauss laser beams can be described as a continuous transition between the well-known Hermite-Gauss (HG) and Laguerre-Gauss (LG) laser beams. A spatial light modulator (SLM) was made by removing the liquid crystal display (LCD) from an overhead projector. The homemade SLM, encoded with a computer-generated hologram, was then used to convert a fundamental Gaussian beam from a small frame Helium-Neon (HeNe) laser into several different orders of Generalized-Gauss (GG) beams. The experimentally generated GG beam profiles matched the theoretically expected profiles
Tribological Studies on Scuffing Due to the Influence of Carbon Dioxide Used as a Refrigerant in Compressors
The refrigeration and air conditioning industry has expressed a great interest in the use of carbon dioxide
(CO2) as a refrigerant. CO2 is anticipated to replace HFC refrigerants, which are known to have a negative effect on
the environment. The reason behind the interest in CO2 is the fact that it is a natural refrigerant, thus
environmentally acceptable. Of course, such a replacement raises concerns regarding design criteria and
performance due to the different thermodynamic properties of CO2 and the very different range of pressures required
for the CO2 refrigeration cycle.
So far, work related to CO2 has been done from a thermodynamics point of view and researchers have
made significant progress developing automotive and portable air-conditioning systems that use the environmentally
friendly carbon dioxide as a refrigerant. The purpose of this work is to develop an understanding of how CO2 plays
a role from a tribology standpoint. More specifically, the goal of this work is to gain an understanding on how CO2
influences friction, lubrication, wear and scuffing of tribological pairs used in compressors.
Work in the area of tribology related to CO2 is very limited. Preliminary work by Cusano and coworkers
showed that consistent data for tests using CO2 could not be acquired nor could a satisfactory explanation be offered
for the inconsistency. Their results triggered the initiation of the work presented here. In this first attempt to
understand the tribological behavior of CO2 several problems were encountered. During this work we noted that its
behavior, unlike conventional refrigerants, could not always be predicted. We believe that this can be attributed to
the thermodynamic properties of CO2, which cannot be ignored when studying its tribological behavior.
Thermodynamic Properties such as miscibility are very important when tribological testing is performed. A limiting
factor with our tester was that it was not designed for CO2 testing, but for other conventional refrigerants and
therefore made previously developed testing protocols non-applicable with CO2. Through a different approach and
some modifications to our tester we were able to establish a protocol for testing under the presence of CO2. CO2
was then compared to R134a and the experimental results showed that it performs equally well.Air Conditioning and Refrigeration Project 13
Forbidden Fruit: Sexual Victimization of Migrant Workers in America\u27s Farmlands
There is a place in the booming agricultural fields of America\u27s farmlands that carries a terrible history. The fields de calzons, or fields of panties, are where female farmworkers, mostly migrant employees residing in the United States for the harvest, are systematically violated by foremen, colleagues, and other superiors. There are 1.4 million crop workers in the United States. Twenty-four percent of these workers are estimated to be female. A recent report suggests that as many as eighty percent of female farmworkers surveyed are regularly exposed to sexual harassment, assault, and trauma, ranging from continuous sexual advances over years of seasonal work to isolated, violent attacks. This note discusses the ways Title VII fails female farmworkers; it suggests a plan of action to implement stronger mechanisms protecting women and girls who face sexual violence in America\u27s farmlands and fields and grounds that call for broader federal protection in a proposed amendment to the legislation meant to safeguard this group of laborers, the Migrant and Seasonal Workers Protection Act ( AWPA )
Reflections from the Road: Vincentian Hospitality Principles in Healthcare Education for the Indigent
Hospitality and health care are clearly connected, both etymologically and practically. Health care has traditionally been delivered in hospitals. Vincent de Paul and Louise de Marillac developed the concept and practice of Vincentian health care, demonstrating a preferential option for the poor. It is important that those who work in healthcare understand and remain committed to Vincentian and hospitality based health care, particularly for the indigent and marginalized. The need for Vincentian and hospitality-based health care remains relevant and necessary in contemporary society, as there remains health inequity, particularly for the poor
Young Children’s Understanding of Beliefs About Moral and Conventional Rule Violations
Children of ages 3–5 (N = 62) were assessed by using standard theory-of-mind tasks and unusual belief tasks related to false information and beliefs endorsing violations of moral (welfare and fairness) and social conventional (school rules) domains. Younger children (under 5 years) did not accurately attribute unusual factual beliefs or beliefs endorsing rule violations whether or not they passed the standard theory-of-mind tasks. Only participants over age 5 performed above chance in attributions of unusual beliefs. Domain differences indicated that beliefs endorsing harm were often most difficult for children, perhaps because the beliefs were the least plausible and most obligatory
Habitat selection and use movements and home range of Malayan gaur (Bos gaurus hubbacki) in central Pahang Malaysia
Development of a Mission-Aligned Campus-Community Partnership Model: The Urban Institute Flu Vaccine Initiative for the Indigent of NYC
Despite its position as a powerful country which offers the opportunity for state-of-the-art high-quality patient-centered care, many people within the U.S. do not have access to or cannot afford health care. The Urban Institute of the College of Pharmacy and Health Sciences at St. John’s University was successful in developing a community outreach initiative that provided free flu vaccines to an underserved indigent patient population in New York City in an effort to decrease their risk for flu-related morbidity and mortality
- …