1,899 research outputs found
Social marketing: Immunizing against unethical practice
A simple approach for the catalytic conversion of primary alcohols into their corresponding esters and amides, with evolution of H2 gas using in situ formed ruthenium PNP- and PNN-pincer catalysts, is presented. The evaluation showed conversions for the esterification with turnover numbers as high as 4300, and 4400 for the amidation
Radiative corrections and parity nonconservation in heavy atoms
The self-energy and the vertex radiative corrections to the effect of parity
nonconservation in heavy atoms are calculated analytically in orders Z alpha^2
and Z^2 alpha^3 ln(lambda_C/r_0), where lambda_C and r_0 being the Compton
wavelength and the nuclear radius, respectively. The value of the radiative
correction is -0.85% for Cs and -1.41% for Tl. Using these results we have
performed analysis of the experimental data on atomic parity nonconservation.
The obtained values of the nuclear weak charge,
Q_W=-72.90(28)_{exp}(35)_{theor} for Cs, and Q_W=-116.7(1.2)_{exp}(3.4)_{theor}
for Tl, agree with predictions of the standard model. As an application of our
approach we have also calculated analytically dependence of the Lamb shift on
the finite nuclear size.Comment: 4 pages, 4 figure
Convergence of the stochastic Euler scheme for locally Lipschitz coefficients
Stochastic differential equations are often simulated with the Monte Carlo
Euler method. Convergence of this method is well understood in the case of
globally Lipschitz continuous coefficients of the stochastic differential
equation. The important case of superlinearly growing coefficients, however,
has remained an open question. The main difficulty is that numerically weak
convergence fails to hold in many cases of superlinearly growing coefficients.
In this paper we overcome this difficulty and establish convergence of the
Monte Carlo Euler method for a large class of one-dimensional stochastic
differential equations whose drift functions have at most polynomial growth.Comment: Published at http://www.springerlink.com/content/g076w80730811vv3 in
the Foundations of Computational Mathematics 201
Urban-rural comparison of adult day care centres in British Columbia
In 1979, Adult Day Care became a part of the B.C. Ministry of Health\u27s Continuing Care Program. By 1989, there were 49 centres in operation in the province and it was felt timely to undertake a comprehensive review of the Adult Day Care component of the Continuing Care Program. As part of that review and as an aid for future planning, the Simon Fraser University Gerontology Research Centre was commissioned to conduct a study that would provide information concerning: 1. activities and services provided by the 49 centres; 2. characteristics of the clients currently being served; 3. reasons clients are referred to Adult Day Care; 4. reasons some referred clients do not attend; and 5. the referral process and the interface between the Long Term Care Program and Adult Day Care
Adult day care centres in British Columbia : their operating characteristics, activities and services, clients, and interface with the long term care program. Final report.
Previews the literature concerning the objectives, models of service delivery, operating characteristics, activities, services and clients of Adult Day Care (ADC) Centres. Presents findings from a 3-phase study conducted in British Columbia. In phase 1, a 100% sample of B.C. ADCs provided information on their operating characteristics, activities and services. In phase 2, the characteristics of 479 new admissions to 22 ADCs were determined. Phase 3 focused on reasons for referring clients to ADC, why some referred clients do not attend and on the interface between ADCs and the province\u27s Continuing Care Program
Bremsstrahlung in alpha-Decay Reexamined
A high-statistics measurement of bremsstrahlung emitted in the alpha decay of
210Po has been performed, which allows to follow the photon spectra up to
energies of ~ 500 keV. The measured differential emission probability is in
good agreement with our theoretical results obtained within the quasi classical
approximation as well as with the exact quantum mechanical calculation. It is
shown that due to the small effective electric dipole charge of the radiating
system a significant interference between the electric dipole and quadrupole
contributions occurs, which is altering substantially the angular correlation
between the alpha particle and the emitted photon.Comment: 10 pages, 5 figures, v2: fix of small typo
Ab initio Investigation of Elasticity and Stability of Metal Aluminum
On the basis of the pseudopotential plane-wave(PP-PW) method in combination
with the local-density-functional theory(LDFT), complete stress-strain curves
for the uniaxial loading and uniaxial deformation along the [001] and [111]
directions, and the biaxial proportional extension along [010] and [001] of
aluminium are obtained. During the uniaxial loading, certain general behaviors
of energy versus stretch and the load versus the stretch are confirmed; in each
acse, there exist three special unstressed structures: f.c.c., b.c.c. and
f.c.t. for [001]; f.c.c., s.c. and b.c.c. for [111]. Using stability criteria,
we find that all of these state are unstable, and always occur together with
shear instability, except the natural f.c.c. structure. A Bain transformation
from the stable f.c.c. structure to the stable b.c.c. configuration cannot be
obtained by uniaxial compression along any equivalent [001] and [111]
direction. The tensile strength are similar for the two directions. For the
higher energy barrier of [111] direction, the compressive strength is greater
than that for the [001] direction. With increase in the ratio of the biaxial
proportional extension, the stress and tensile strength increase; however, the
critical strain does not change significantly. Our results add to the existing
ab initio database for use in fitting and testing interatomic potentials.Comment: 9 Pages in Revtex and 11 Eps figure
Corrections to deuterium hyperfine structure due to deuteron excitations
We consider the corrections to deuterium hyperfine structure originating from
the two-photon exchange between electron and deuteron, with the deuteron
excitations in the intermediate states. In particular, the motion of the two
intermediate nucleons as a whole is taken into account. The problem is solved
in the zero-range approximation. The result is in good agreement with the
experimental value of the deuterium hyperfine splitting.Comment: 7 pages, LaTe
Evaluation of the screened vacuum-polarization corrections to the hyperfine splitting of Li-like bismuth
The rigorous calculation of the vacuum-polarization screening corrections to
the hyperfine splitting in Li-like bismuth is presented. The two-electron
diagrams with electric and magnetic vacuum-polarization loops are evaluated to
all orders in alpha*Z, including the Wichmann-Kroll contributions. This
improves the accuracy of the theoretical prediction for the specific difference
of the hyperfine splitting values of H- and Li-like bismuth.Comment: 18 pages with 4 figure
Studies of New Vector Resonances at the CLIC Multi-TeV e+e- Collider
Several models predict the existence of new vector resonances in the
multi-TeV region, which can be produced in high energy e+e- collisions in the
s-channel. In this paper we review the existing limits on the masses of these
resonances from LEP/SLC and TEVATRON data and from atomic parity violation in
some specific models. We study the potential of a multi-TeV e+e- collider, such
as CLIC, for the determination of their properties and nature.Comment: 17 pages, 16 EPS figures, uses JHEP3.cl
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