555 research outputs found
Anisometric Charge Dependent Swelling of Porous Carbon in an Ionic Liquid
In situ electrochemical dilatometry was used to study, for the first time,
the expansion behavior of a porous carbon electrode in a pure ionic liquid,
1-ethyl-3-methyl-imidazolium-tetrafluoroborate. For a single electrode, an
applied potential of -2 V and +2 V against the potential of zero charge
resulted in maximum strain of 1.8 % and 0.5 %, respectively. During cyclic
voltammetry, the characteristic expansion behavior strongly depends on the scan
rate, with increased scan rates leading to a decrease of the expansion.
Chronoamperometry was used to determine the equilibrium specific capacitance
and expansion. The obtained strain versus accumulated charge relationship can
be fitted with a simple quadratic function. Cathodic and anodic expansion data
collapses on one parabola when normalizing the surface charge by the ratio of
ion volume and average pore size. There is also a transient spike in the height
change when polarity is switched from positive to negative that is not observed
when changing the potential from negative to positive indicating the size and
the shape of the ion is influencing the expansion behavior.Comment: 10 pages double spaced, 3 figs, Electrochemistry Communications,
accepte
Degradation analysis of tribologically loaded carbon nanotubes and carbon onions
Coating laser-patterned stainless-steel surfaces with carbon nanotubes (CNT) or carbon onions (CO) forms a tribological system that
provides effective solid lubrication. Lubricant retention represents the fundamental mechanism of this system, as storing the
particles inside the pattern prevents lubricant depletion in the contact area. In previous works, we used direct laser interference
patterning to create line patterns with three different structural depths on AISI 304 stainless-steel platelets. Electrophoretic
deposition subsequently coated the patterned surfaces with either CNTs or COs. Ball-on-disc friction tests were conducted to study
the effect of structural depth on the solid lubricity of as-described surfaces. The results demonstrated that the shallower the
textures, the lower the coefficient of friction, regardless of the applied particle type. This follow-up study examines the carbon
nanoparticles’ structural degradation after friction testing on substrates patterned with different structural depths (0.24, 0.36, and
0.77 µm). Raman characterization shows severe degradation of both particle types and is used to classify their degradation state
within Ferrari’s three-stage amorphization model. It was further shown that improving CNT lubricity translates into increasing
particle defectivity. This is confirmed by electron microscopy, which shows decreasing crystalline domains. Compared to CNTs, COderived tribofilms show even more substantial structural degradation
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Work relations and the multiple dimensions of the work-life boundary: Hairstyling at home
This article proposes a multidimensional approach to analysis of the work-life boundary and examines the affects of particular social and organizational relations on the preservation or porous-ness of different dimensions. In line with Nippert-Eng (1996), it is suggested that different dimensions of the boundary are reinforced or weakened by different social and organizational pressures. Analysis describes a specific type of multidimensional breaching – instances when work is taken outside of the worksite (spatial breaching) and is carried out outside of work-time (temporal breaching). Empirical research was conducted among hairstylists working in salons and barbershops in a city in the North of England. Because of the nature of the tasks involved in hairstyling – that the skills involved are widely exchangeable and so may be employed in extra-work environments and temporalities – hairstylists provide a nice site for investigating the circumstances when this does (or does not) occur. Data collection involved a comprehensive self-completion survey of salons and barbershops in the city (response rate: 40%; N=132) and semi-structured interviews with 70 stylists working in 52 salons or barbershops. Findings demonstrate that work relations (hairstylists’ structural relations of production – whether a worker is an owner-proprietor, chair-renter, on-commission stylist, basic-only stylist, or trainee) are critical in determining both workers’ ability and desire to resist the seepage of work into their social lives as well as the particular dimensions of the boundary that are breached. This is because work relations affect the relative importance of four identified motivations for taking work out of the salon (income production; training; inter-personal reciprocity rooted in social relations; and inter-personal reciprocity rooted in the workplace)
Quantitative microbiology: a basis for food safety.
Because microorganisms are easily dispersed, display physiologic diversity, and tolerate extreme conditions, they are ubiquitous and may contaminate and grow in many food products. The behavior of microbial populations in foods (growth, survival, or death) is determined by the properties of the food (e.g., water activity and pH) and the storage conditions (e.g., temperature, relative humidity, and atmosphere). The effect of these properties can be predicted by mathematical models derived from quantitative studies on microbial populations. Temperature abuse is a major factor contributing to foodborne disease; monitoring temperature history during food processing, distribution, and storage is a simple, effective means to reduce the incidence of food poisoning. Interpretation of temperature profiles by computer programs based on predictive models allows informed decisions on the shelf life and safety of foods. In- or on-package temperature indicators require further development to accurately predict microbial behavior. We suggest a basis for a "universal" temperature indicator. This article emphasizes the need to combine kinetic and probability approaches to modeling and suggests a method to define the bacterial growth/no growth interface. Advances in controlling foodborne pathogens depend on understanding the pathogens' physiologic responses to growth constraints, including constraints conferring increased survival capacity
Religious faith and psychosocial adaptation among stroke patients in Kuwait: A mixed method study
This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2012 Springer Science+Business Media.Religious faith is central to life for Muslim patients in Kuwait, so it may influence adaptation and rehabilitation. This study explored quantitative associations among religious faith, self-efficacy, and life satisfaction in 40 female stroke patients and explored the influence of religion within stroke rehabilitation through qualitative interviews with 12 health professionals. The quantitative measure of religious faith did not relate to life satisfaction or self-efficacy in stroke patients. However, the health professionals described religious coping as influencing adaptation post-stroke. Fatalistic beliefs were thought to have mixed influences on rehabilitation. Measuring religious faith among Muslims through a standardized scale is debated. The qualitative accounts suggest that religious beliefs need to be acknowledged in stroke rehabilitation in Kuwait
Deconstructing the lesbian, gay, bisexual, transgender victim of sex trafficking: Harm, exceptionality and religion–sexuality tensions
Contrary to widespread belief, sex trafficking also targets lesbian, gay, bisexual, transgender (LGBT) communities. Contemporary social and political constructions of victimhood lie at the heart of regulatory policies on sex trafficking. Led by the US Department of State, knowledge about LGBT victims of trafficking constitutes the newest frontier in the expansion of criminalization measures. These measures represent a crucial shift. From a burgeoning range of preemptive measures enacted to protect an amorphous class of ‘all potential victims’, now policies are heavily premised on the risk posed by traffickers to ‘victims of special interest’. These constructed identities, however, are at odds with established structures. Drawing on a range of literatures, the core task of this article is to confront some of the complexities and tensions surrounding constructions of LGBT trafficking victims. Specifically, the article argues that discourses of ‘exceptional vulnerability’ and the polarized notions of ‘innocence’ and ‘guilt’ inform hierarchies of victimhood. Based on these insights, the article argues for the need to move beyond monolithic understandings of victims, by reframing the politics of harm accordingly
Health and Well-Being of International University Students, and Comparison with Domestic Students, in Tasmania, Australia
International students comprise an increasingly larger proportion of higher education students globally. Empirical evidence about the health and well-being of these students is, however, limited. We sought to examine the health and well-being of international students, primarily from Asian countries, attending the University of Tasmania, Australia, using domestic students as a comparison group. Ethics approval was given to invite (via email) all currently enrolled students to participate in the study by completing a pilot-tested, online survey. The survey was completed by 382 international students (response rate = 8.9%) and 1013 domestic students (9.2%). Independent samples t-tests, analysis of variance (ANOVA) and chi-square tests were used for bivariate comparisons between international and domestic students, and between subgroups of international students. Regression models were used to examine the associations between student status (international vs. domestic) and health outcomes, controlling for demographic and enrolment variables. International students, particularly male students, were found to be at increased risk of several adverse health outcomes while also being less likely to seek help for mental health and related problems. The findings indicate the need for accessible, targeted, culturally-sensitive health promotion and early intervention programs
The Willingness to Pay for Job Amenities: Evidence from Mothers' Return to Work
This study is the first to estimate mother's marginal willingness to pay (MWP) for job amenities directly. Its identification strategy relies on German maternity leave length. The key aspect of the maternal leave framework is that mothers can decide whether and when to return to their guaranteed job. Thus, in contrast to previous studies that analyze the job search of employed workers, this framework allows us to overcome the limitation of not observing the wage/amenity offer process. A theoretical model of the leave length decision is derived from a random utility approach. Using data from the German Socio-Economic Panel and the Qualification and Career Survey, this model is estimated by a discrete duration method. The MWP for amenities can be inferred through the estimated elasticities of the leave length with respect to the amenities and the wage. The results provide evidence that mothers are willing to sacrifice a significant fraction of their wage to reduce hazards (22%) and to enjoy a flexible working schedule (36-56%)
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