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2.
J Res Natl Inst Stand Technol ; 110(3): 185-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-27308119

RESUMO

A test experiment has shown that the number of ultracold neutrons (UCN) of one polarization state, transmitted through a 100 µm Al foil when placed in a 5 T magnetic field, is greater by 3.8 times. The increased transmission is due to the higher velocity of the UCN passing through the foil.

3.
J Res Natl Inst Stand Technol ; 110(3): 289-91, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-27308138

RESUMO

A silicon ultracold neutron (UCN) detector with an area of 45 cm(2) and with a (6)LiF converter is developed at St. Petersburg Nuclear Physics Institute (PNPI). The spectral efficiency of the silicon UCN detector was measured by means of a gravitational spectrometer at Institut Max von Laue - Paul Langevin (ILL). The sandwich-type detector from two silicon plates with a (6)LiF converter placed between them was also studied. Using this type of technology the UCN detector with analysis of polarization was developed and tested. The analyzing power of this detector assembly reaches up 75 % for the main part of UCN spectrum. This UCN detector with analysis of UCN polarization can be used in the new electric dipole moment (EDM) spectrometer.

4.
J Res Natl Inst Stand Technol ; 110(4): 333-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-27308146

RESUMO

We present a new value for the neutron lifetime of 878.5 ± 0.7stat. ± 0.3syst. This result differs from the world average value by 6.5 standard deviations and by 5.6 standard deviations from the previous most precise result. However, this new value for the neutron lifetime together with a ß-asymmetry in neutron decay, A 0, of -0.1189(7) is in a good agreement with the Standard Model.

5.
J Res Natl Inst Stand Technol ; 110(4): 345-50, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-27308148

RESUMO

Further improvement in the accuracy of any neutron lifetime experiment by means of ultracold neutrons (UCN) in material bottles is limited due to unavoidable systematic effects when the UCN are reflected from the walls. However, such effects can be excluded in principle if magnetic trapping of UCN is used. The storage of UCN in a small magnetic trap made of permanent magnets was demonstrated for the first time ever. The measured storage time in this feasibility study was (882 ± 16) s. At this level of accuracy no depolarization was observed.

6.
J Res Natl Inst Stand Technol ; 110(4): 383-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-27308154

RESUMO

We are going to use a polarized cold neutron beam and an axial magnetic field in the shape of a bottle formed by a superconducting magnetic system. Such a configuration of magnetic fields allows us to extract the decay electrons inside a well-defined solid angle with high accuracy. An electrostatic cylinder with a potential of 25 kV defines the detected region of neutron decays. The protons, which come from this region will be accelerated and registered by a proton detector. The use of coincidences between electron and proton signals will allow us to considerably suppress the background. The final accuracy of the A-asymmetry will be determined by the uncertainty of the neutron beam polarization measurement which is at the level of (1-2) × 10(-3), as shown in previous studies.

7.
J Res Natl Inst Stand Technol ; 110(4): 461-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-27308168

RESUMO

An experiment aiming at the simultaneous determination of both transversal polarization components of electrons emitted in the decay of free neutrons begins data taking using the polarized cold neutron beam (FUNSPIN) from the Swiss Neutron Spallation Source (SINQ) at the Paul-Scherrer Institute, Villigen. A non-zero value of R due to the e(-) polarization component, which is perpendicular to the plane spanned by the spin of the decaying neutron and the electron momentum, would signal a violation of time reversal symmetry and thus physics beyond the Standard Model. Present status of the project and the results from analysis of the first data sample will be discussed.

8.
J Res Natl Inst Stand Technol ; 110(4): 491-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-27308173

RESUMO

Solid deuterium (sD2) will be used for the production of ultra-cold neutrons (UCN) in a new generation of UCN sources. Scattering cross sections of UCN in sD2 determine the source yield but until now have not been investigated. We report first results from transmission and scattering experiments with cold, very cold and ultra-cold neutrons on sD2 along with light transmission and Raman scattering studies showing the influence of the sD2 crystal properties.

9.
Ter Arkh ; 70(2): 50-4, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9551574

RESUMO

AIM: Assessment of the antihypertensive effect of doxazosin, alpha-1 blocker, as well as its action on lipid and carbohydrate metabolism, microcirculation and platelet function in patients with non-insulin-dependent diabetes mellitus (NIDDM). MATERIALS AND METHODS: Doxazosin (tonocardin) treatment was given for 11 weeks to 33 NIDDM patients with concomitant hypertension. The clinical examination comprised evaluation of central hemodynamics, vessels of the fundus of eye, lipid and carbohydrate metabolism, renal function, platelet aggregation. RESULTS: Tonocardin produced a fall in the systolic blood pressure (BP) by 14%, in the diastolic BP--by 17%. The 24-h profile of BP, lipid and purine metabolism, microcirculation of the vessels of the fundus of eye also improved. Total peripheral vascular resistance, left ventricular myocardial mass and platelet aggregation. Carbohydrate metabolism remained unchanged. CONCLUSION: Monotherapy with tonocardin (2-8 mg/day) is effective and safe in the treatment of arterial hypertension in NIDDM patients.


Assuntos
Anti-Hipertensivos/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Doxazossina/uso terapêutico , Hipertensão/tratamento farmacológico , Idoso , Anti-Hipertensivos/efeitos adversos , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Doxazossina/efeitos adversos , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Hipertensão/sangue , Hipertensão/fisiopatologia , Resistência à Insulina , Masculino , Estatísticas não Paramétricas , Fatores de Tempo
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