132 research outputs found
Contact Angle Measurement is an Efficient Tool for the Characterization of Corrosion Pro-tection Nanolayers on Copper Alloys and Stainless Steel
With the advent of the nano-era, a pronounced interest in the nanolayers has emerged. The develop-ment of more and more sophisticated measurement devices and techniques made possible the visualiza-tion, characterization and investigation of nanolayers. However, there exists a variety of simple, old means which should not be despised either. In this work, the use of contact angle measurement as a simple, fast, inexpensive and accessible tool for the study of surfaces with and without nanolayers is demonstrated. Furthermore, it is evidenced that in contrast to its simplicity, contact angle measurement can address sur-prisingly complex questions and give proper answers to these.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3525
Atomic parity nonconservation and neutron radii in cesium isotopes
The interpretation of future precise experiments on atomic parity violation
in terms of parameters of the Standard Model could be hampered by uncertainties
in the atomic and nuclear structure. While the former can be overcome by
measurement in a series of isotopes, the nuclear structure requires knowledge
of the neutron density. We use the nuclear Hartree-Fock method, which includes
deformation effects, to calculate the proton and neutron densities in
{125}Cs-{139}Cs. We argue that the good agreement with the experimental charge
radii, binding energies, and ground state spins signifies that the
phenomenological nuclear force and the method of calculation that we use is
adequate. Based on this agreement, and on calculations involving different
effective interactions, we estimate the uncertainties in the differences of the
neutron radii delta_{N,N'} and conclude that they cause uncertainties in
the ratio of weak charges, the quantities determined in the atomic parity
nonconservation experiments, of less than 10^{-3}. Such an uncertainty is
smaller than the anticipated experimental error.Comment: 24 pages (RevTeX) 4 figures (Postscript/uuencoded compressed) Caltech
Preprint No. MAP-153 (March 1993
The angular distribution of the reaction
The reaction is very important for low-energy
( MeV) antineutrino experiments. In this paper we calculate
the positron angular distribution, which at low energies is slightly backward.
We show that weak magnetism and recoil corrections have a large effect on the
angular distribution, making it isotropic at about 15 MeV and slightly forward
at higher energies. We also show that the behavior of the cross section and the
angular distribution can be well-understood analytically for MeV by calculating to , where is the nucleon mass. The
correct angular distribution is useful for separating events from other reactions and detector backgrounds, as well as for
possible localization of the source (e.g., a supernova) direction. We comment
on how similar corrections appear for the lepton angular distributions in the
deuteron breakup reactions and . Finally, in the reaction , the
angular distribution of the outgoing neutrons is strongly forward-peaked,
leading to a measurable separation in positron and neutron detection points,
also potentially useful for rejecting backgrounds or locating the source
direction.Comment: 10 pages, including 5 figure
Induced pseudoscalar coupling of the proton weak interaction
The induced pseudoscalar coupling is the least well known of the weak
coupling constants of the proton's charged--current interaction. Its size is
dictated by chiral symmetry arguments, and its measurement represents an
important test of quantum chromodynamics at low energies. During the past
decade a large body of new data relevant to the coupling has been
accumulated. This data includes measurements of radiative and non radiative
muon capture on targets ranging from hydrogen and few--nucleon systems to
complex nuclei. Herein the authors review the theoretical underpinnings of
, the experimental studies of , and the procedures and uncertainties
in extracting the coupling from data. Current puzzles are highlighted and
future opportunities are discussed.Comment: 58 pages, Latex, Revtex4, prepared for Reviews of Modern Physic
Development of the interRAI Pressure Ulcer Risk Scale (PURS) for use in long-term care and home care settings
<p>Abstract</p> <p>Background</p> <p>In long-term care (LTC) homes in the province of Ontario, implementation of the Minimum Data Set (MDS) assessment and The Braden Scale for predicting pressure ulcer risk were occurring simultaneously. The purpose of this study was, using available data sources, to develop a bedside MDS-based scale to identify individuals under care at various levels of risk for developing pressure ulcers in order to facilitate targeting risk factors for prevention.</p> <p>Methods</p> <p>Data for developing the interRAI Pressure Ulcer Risk Scale (interRAI PURS) were available from 2 Ontario sources: three LTC homes with 257 residents assessed during the same time frame with the MDS and Braden Scale for Predicting Pressure Sore Risk, and eighty-nine Ontario LTC homes with 12,896 residents with baseline/reassessment MDS data (median time 91 days), between 2005-2007. All assessments were done by trained clinical staff, and baseline assessments were restricted to those with no recorded pressure ulcer. MDS baseline/reassessment samples used in further testing included 13,062 patients of Ontario Complex Continuing Care Hospitals (CCC) and 73,183 Ontario long-stay home care (HC) clients.</p> <p>Results</p> <p>A data-informed Braden Scale cross-walk scale using MDS items was devised from the 3-facility dataset, and tested in the larger longitudinal LTC homes data for its association with a future new pressure ulcer, giving a c-statistic of 0.676. Informed by this, LTC homes data along with evidence from the clinical literature was used to create an alternate-form 7-item additive scale, the interRAI PURS, with good distributional characteristics and c-statistic of 0.708. Testing of the scale in CCC and HC longitudinal data showed strong association with development of a new pressure ulcer.</p> <p>Conclusions</p> <p>interRAI PURS differentiates risk of developing pressure ulcers among facility-based residents and home care recipients. As an output from an MDS assessment, it eliminates duplicated effort required for separate pressure ulcer risk scoring. Moreover, it can be done manually at the bedside during critical early days in an admission when the full MDS has yet to be completed. It can be calculated with established MDS instruments as well as with the newer interRAI suite instruments designed to follow persons across various care settings (interRAI Long-Term Care Facilities, interRAI Home Care, interRAI Palliative Care).</p
The Method for Assigning Priority Levels (MAPLe): A new decision-support system for allocating home care resources
<p>Abstract</p> <p>Background</p> <p>Home care plays a vital role in many health care systems, but there is evidence that appropriate targeting strategies must be used to allocate limited home care resources effectively. The aim of the present study was to develop and validate a methodology for prioritizing access to community and facility-based services for home care clients.</p> <p>Methods</p> <p>Canadian and international data based on the Resident Assessment Instrument – Home Care (RAI-HC) were analyzed to identify predictors for nursing home placement, caregiver distress and for being rated as requiring alternative placement to improve outlook.</p> <p>Results</p> <p>The Method for Assigning Priority Levels (MAPLe) algorithm was a strong predictor of all three outcomes in the derivation sample. The algorithm was validated with additional data from five other countries, three other provinces, and an Ontario sample obtained after the use of the RAI-HC was mandated.</p> <p>Conclusion</p> <p>The MAPLe algorithm provides a psychometrically sound decision-support tool that may be used to inform choices related to allocation of home care resources and prioritization of clients needing community or facility-based services.</p
Layer formation by 1,7-diphosphono-heptane
Surface modification of polycrystalline ARMCO iron and an Fe(110) single crystal was performed using a solution of 1,7-diphosphono-heptane (DPH). The changes of the surface properties were studied by subtractively normalised interfacial Fourier transform infrared spectroscopy (SNIFTIRS), scanning tunneling microscopy (STM) and electrochemical impedance spectroscopy (EIS). The immersion of the surfaces into DPH solution resulted in a build up of an ordered thin multimolecular layer after a few hours of continuous adsorption. The orientation of the DPH molecules was influenced by the supporting electrolyte and the electrode potential. The treatment in the absence of oxygen resulted in a lower corrosion protection effect compared to diphosphonate layer formation in an atmospheric environment
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