332 research outputs found
The magnetic field influence on magnetostructural phase transition in Ni2.19Mn0.81Ga
Magnetic properties of a polycrystalline alloy NiMnGa,
which undergoes a first-order magnetostructural phase transition from cubic
paramagnetic to tetragonal ferromagnetic phase, are studied. Hysteretic
behavior of isothermal magnetization has been observed in a temperature
interval of the magnetostructural transition in magnetic fields from 20 to 100
kOe. Temperature dependencies of magnetization , measured in magnetic fields
and 60 kOe, indicate that the temperature of the magnetostructural
transition increases with increasing magnetic field.Comment: Presented at the Second Moscow International Symposium on Magnetism
(Moscow-2002
Особенности выделения передних большеберцовых сосудов при формировании костных васкуляризированных трансплантатов
Background. The currently existing techniques for dissection the anterior tibial vascular bundle in the proximal third of the lower leg do not provide sufficient length of the vascular pedicle to rotate the tibial bone graft to the level of the middle third of the thigh.
The aim of the study to substantiate the possibility of pedicled transfer to the level of the thigh middle third of two blood-supplied bone autografts on a common permanent pedicle, including the anterior tibial vascular bundle.
Material and Methods. The study was conducted on 62 lower limbs of non-fixed (native) corpses. We studied the topographic and anatomical relationship between the anterior tibial vascular bundle and the deep peroneal nerve at the level of the proximal third of the leg.
Results. The distance between the tip of the greater trochanter of the femur and the distal edge of the anterior tibial bone graft using a combination of grafts at the same level in men was Me 176.7 [173.7; 193.9] mm, in women Me = 151.6 [146.9; 159.9] mm. An analysis of limb lengths ratios in men and women indicates standard level that can be achieved with graft rotation in each person.
Conclusion. Dissection of the anterior tibial vascular bundle at the level of the proximal third of the lower leg allows rotation of the complex of the anterior tibial bone autograft and the autograft of the second metatarsal bone into the area of the middle third of the femur on a single vascular bundle. Prevention of injury to the deep peroneal nerve branches during dissection of the vascular pedicle requires the use of microsurgical techniques and preoperative preparation.Актуальность. Существующие в настоящее время методики выделения переднего большеберцового сосудистого пучка (ПББСП) в проксимальной трети голени не обеспечивают достаточной длины сосудистой ножки для ротации костного трансплантата большеберцовой кости до уровня средней трети бедра.
Цель исследования обосновать возможность выполнения операций несвободной пересадки на уровень средней трети бедра двух кровоснабжаемых костных аутотрансплантатов на общей постоянной питающей ножке, включающей ПББСП.
Материал и методы. Исследование проведено на 62 нижних конечностях нефиксированных (нативных) трупов людей. Изучали топографо-анатомические взаимоотношения ПББСП и глубокого малоберцового нерва на уровне проксимальной трети голени.
Результаты. Расстояние между верхушкой большого вертела бедренной кости и дистальным краем костного переднего большеберцового трансплантата при использовании комбинации трансплантатов на одном уровне составило: у мужчин Ме = 176,7 [173,7; 193,9] мм, у женщин Ме = 151,6 [146,9; 159,9] мм. Анализ соотношений длины конечностей у мужчин и женщин свидетельствует о стандартном уровне, который можно достичь при ротации трансплантатов у каждого человека.
Заключение. Выделение ПББСП на уровне проксимальной трети голени позволяет ротировать на едином сосудистом пучке комплекс переднего большеберцового костного аутотрансплантата и аутотрансплантата второй плюсневой кости в зону средней трети бедренной кости. Предотвращение повреждения ветвей глубокого малоберцового нерва в ходе выделения сосудистой ножки требует использования микрохирургической техники и предоперационной подготовки
Один из способов управления технологическим процессом дуговой сталеплавильной печи
В статье приводится описание комплексной математической модели, используемой для рационального управления работой дуговых электросталеплавильных печей.In article the description of the complex mathematical model used for rational management by work of arc electrosteel-smelting furnaces is resulted
The Stress-Energy Tensor in Soluble Models of Spherically Symmetric Charged Black Hole Evaporation
We study the decay of a near-extremal black hole in AdS, related to the
near-horizon region of 3+1-dimensional Reissner-Nordstr\"om spacetime,
following Fabbri, Navarro, and Navarro-Salas. Back-reaction is included in a
semiclassical approximation. Calculations of the stress-energy tensor of matter
coupled to the physical spacetime for an affine null observer demonstrate that
the black hole evaporation proceeds smoothly and the near-extremal black hole
evolves back to an extremal ground state, until this approximation breaks down.Comment: 19 pages, 14 figure
Inhomogeneous Magnetism in La-doped CaMnO3. (II) Mesoscopic Phase Separation due to Lattice-coupled FM Interactions
A detailed investigation of mesoscopic magnetic and crystallographic phase
separation in Ca(1-x)La(x)MnO3, 0.00<=x<=0.20, is reported. Neutron powder
diffraction and DC-magnetization techniques have been used to isolate the
different roles played by electrons doped into the eg level as a function of
their concentration x. The presence of multiple low-temperature magnetic and
crystallographic phases within individual polycrystalline samples is argued to
be an intrinsic feature of the system that follows from the shifting balance
between competing FM and AFM interactions as a function of temperature. FM
double-exchange interactions associated with doped eg electrons are favored
over competing AFM interactions at higher temperatures, and couple more
strongly with the lattice via orbital polarization. These FM interactions
thereby play a privileged role, even at low eg electron concentrations, by
virtue of structural modifications induced above the AFM transition
temperatures.Comment: 8 pages, 7 figure
Coronal Shock Waves, EUV waves, and Their Relation to CMEs. I. Reconciliation of "EIT waves", Type II Radio Bursts, and Leading Edges of CMEs
We show examples of excitation of coronal waves by flare-related abrupt
eruptions of magnetic rope structures. The waves presumably rapidly steepened
into shocks and freely propagated afterwards like decelerating blast waves that
showed up as Moreton waves and EUV waves. We propose a simple quantitative
description for such shock waves to reconcile their observed propagation with
drift rates of metric type II bursts and kinematics of leading edges of coronal
mass ejections (CMEs). Taking account of different plasma density falloffs for
propagation of a wave up and along the solar surface, we demonstrate a close
correspondence between drift rates of type II bursts and speeds of EUV waves,
Moreton waves, and CMEs observed in a few known events.Comment: 30 pages, 15 figures. Solar Physics, published online. The final
publication is available at http://www.springerlink.co
Model-independent search for CP violation in D0→K−K+π−π+ and D0→π−π+π+π− decays
A search for CP violation in the phase-space structures of D0 and View the MathML source decays to the final states K−K+π−π+ and π−π+π+π− is presented. The search is carried out with a data set corresponding to an integrated luminosity of 1.0 fb−1 collected in 2011 by the LHCb experiment in pp collisions at a centre-of-mass energy of 7 TeV. For the K−K+π−π+ final state, the four-body phase space is divided into 32 bins, each bin with approximately 1800 decays. The p-value under the hypothesis of no CP violation is 9.1%, and in no bin is a CP asymmetry greater than 6.5% observed. The phase space of the π−π+π+π− final state is partitioned into 128 bins, each bin with approximately 2500 decays. The p-value under the hypothesis of no CP violation is 41%, and in no bin is a CP asymmetry greater than 5.5% observed. All results are consistent with the hypothesis of no CP violation at the current sensitivity
Search for the lepton-flavor-violating decays Bs0→e±μ∓ and B0→e±μ∓
A search for the lepton-flavor-violating decays Bs0→e±μ∓ and B0→e±μ∓ is performed with a data sample, corresponding to an integrated luminosity of 1.0 fb-1 of pp collisions at √s=7 TeV, collected by the LHCb experiment. The observed number of Bs0→e±μ∓ and B0→e±μ∓ candidates is consistent with background expectations. Upper limits on the branching fractions of both decays are determined to be B(Bs0→e±μ∓)101 TeV/c2 and MLQ(B0→e±μ∓)>126 TeV/c2 at 95% C.L., and are a factor of 2 higher than the previous bounds
Measurement of the branching fraction
The branching fraction is measured in a data sample
corresponding to 0.41 of integrated luminosity collected with the LHCb
detector at the LHC. This channel is sensitive to the penguin contributions
affecting the sin2 measurement from The
time-integrated branching fraction is measured to be . This is the most precise measurement to
date
Branching fraction and CP asymmetry of the decays B+→K0Sπ+ and B+→K0SK+
An analysis of B+ → K0
Sπ+ and B+ → K0
S K+ decays is performed with the LHCb experiment. The pp
collision data used correspond to integrated luminosities of 1 fb−1 and 2 fb−1 collected at centre-ofmass
energies of
√
s = 7 TeV and
√
s = 8 TeV, respectively. The ratio of branching fractions and the
direct CP asymmetries are measured to be B(B+ → K0
S K+
)/B(B+ → K0
Sπ+
) = 0.064 ± 0.009 (stat.) ±
0.004 (syst.), ACP(B+ → K0
Sπ+
) = −0.022 ± 0.025 (stat.) ± 0.010 (syst.) and ACP(B+ → K0
S K+
) =
−0.21 ± 0.14 (stat.) ± 0.01 (syst.). The data sample taken at
√
s = 7 TeV is used to search for
B+
c
→ K0
S K+ decays and results in the upper limit ( fc · B(B+
c
→ K0
S K+
))/( fu · B(B+ → K0
Sπ+
)) <
5.8 × 10−2 at 90% confidence level, where fc and fu denote the hadronisation fractions of a ¯b
quark
into a B+
c or a B+ meson, respectively
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