913 research outputs found
Anisotropic interactions of a single spin and dark-spin spectroscopy in diamond
The nitrogen-vacancy (N-V) center in diamond is a promising atomic-scale
system for solid-state quantum information processing. Its spin-dependent
photoluminescence has enabled sensitive measurements on single N-V centers,
such as: electron spin resonance, Rabi oscillations, single-shot spin readout
and two-qubit operations with a nearby 13C nuclear spin. Furthermore, room
temperature spin coherence times as long as 58 microseconds have been reported
for N-V center ensembles. Here, we have developed an angle-resolved
magneto-photoluminescence microscopy apparatus to investigate the anisotropic
electron spin interactions of single N-V centers at room temperature. We
observe negative peaks in the photoluminescence as a function of both magnetic
field magnitude and angle that are explained by coherent spin precession and
anisotropic relaxation at spin level anti-crossings. In addition, precise field
alignment unmasks the resonant coupling to neighboring dark nitrogen spins that
are not otherwise detected by photoluminescence. The latter results demonstrate
a means of investigating small numbers of dark spins via a single bright spin
under ambient conditions.Comment: 13 pages, 4 figure
Proyecto piloto 9x18, una alternativa a la expansión de Santiago
Ponencia que describe el proyecto píloto 9x18 que consiste en la construcción de una nueva vivienda para los allegados en los lotes donde habitan, sin necesidad de adquirir un terreno nuevo
Are Compact High-Velocity Clouds Extragalactic Objects?
Compact high-velocity clouds (CHVCs) are the most distant of the HVCs in the
Local Group model and would have HI volume densities of order 0.0003/cm^3.
Clouds with these volume densities and the observed neutral hydrogen column
densities will be largely ionized, even if exposed only to the extragalactic
ionizing radiation field. Here we examine the implications of this process for
models of CHVCs. We have modeled the ionization structure of spherical clouds
(with and without dark matter halos) for a large range of densities and sizes,
appropriate to CHVCs over the range of suggested distances, exposed to the
extragalactic ionizing photon flux. Constant-density cloud models in which the
CHVCs are at Local Group distances have total (ionized plus neutral) gas masses
roughly 20-30 times larger than the neutral gas masses, implying that the gas
mass alone of the observed population of CHVCs is about 40 billion solar
masses. With a realistic (10:1) dark matter to gas mass ratio, the total mass
in such CHVCs is a significant fraction of the dynamical mass of the Local
Group, and their line widths would exceed the observed FWHM. Models with dark
matter halos fare even more poorly; they must lie within approximately 200 kpc
of the Galaxy. We show that exponential neutral hydrogen column density
profiles are a natural consequence of an external source of ionizing photons,
and argue that these profiles cannot be used to derive model-independent
distances to the CHVCs. These results argue strongly that the CHVCs are not
cosmological objects, and are instead associated with the Galactic halo.Comment: 30 pages, 14 figures; to appear in The Astrophysical Journa
Геомеханика разрушения и регламент тампонажного упрочнения пород вокруг наклонных стволов вязкопластическими растворами
Наведено підсумки шахтних досліджень руйнування порід навколо стволів вугільних шахт та обґрунтовано параметри їх зміцнення вязкопластичними розчинами.Research results are mine destruction of rocks around the shafts of coal mines and reasonable options to strengthen viscoplastic solutions
Subjective well-being and the 2008 recession in European regions
How can we explain why some regions experienced large decreases in subjective well-being during the 2008 recession, while in other regions, the changes were only very modest? Building on the literature on resilience in subjective well-being during periods of crisis, this article explores a related but undervalued factor that moderates the localized relationship between macroeconomic developments and life evaluation: regional quality of governance. We use individual-level data on life satisfaction and personal information taken from Eurobarometer for 89 European regions in the EU-28 for the period of 2005–2014, combined with macroeconomic variables and regional quality of governance data to test for the hypothesized moderating effect of quality of governance. The results demonstrate that increased regional unemployment and financial stress have a less aggravating effect on subjective well-being in regions characterized by a high quality of governance. These results support the capacity of quality of governance to buffer the negative effects of adverse macroeconomic conditions, most likely through generating trust and providing a safety net
Митрополит Андрей Шептицький на владичому престолі (1889-1900 рр.) в Станіславові
Актуальність проблеми, зв’язок її з важливими науковими та практичними завданнями полягає в тому, що призначення Андрея Шептицького ЧСВВ третім Станіславівським Єпископом різко змінило подальший розвиток Станіславівської Української Греко-Католицької Єпархії. Як зазначає д-р Г.Лужницький, “після такого науковця, як Єпископ Ю.Пелеш, та хворого і розчарованого ідеаліста, яким був Юліан Куїловський, молодий, повний ініціативи, Кир Андрей Шептицький був Божою благодаттю нової і ще не зорганізованої як слід Станіславівської Єпархії”
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