462 research outputs found
CARS diagnostics of near-critical fluid in small mesopores
Due to the high spacial resolution and theinterference nature, coherent anti-Stokes Ramanscattering (CARS) spectroscopy is well suited forthe diagnostics of composites based on transparentnanoporous hosts. In particular, the adsorption of afluid on the walls of nanopores and the formation ofa condensed phase in their volume leads to obvioustransformation of the CARS spectra. Recently wehave developed a model which describes thebehavior of molecular spectra at isothermalcompression in cylindrical nanopores. Calculationsbased on the model have shown a good agreementwith the experimental results for carbon dioxide innanoporous glass with pores of diameter of severalnanometers. Here we use the developed approach toinvestigate the phase behavior of carbon dioxide inglass nanopores at near-critical temperatures. It hasbeen experimentally shown that condensation innanopores occurs at relatively low pressures atsubcritical and even at supercritical temperatures.The analysis based on the developed model allowsto reveal some qualitative and quantitativecharacterizations of the shift of critical point
Generation and Collection of Biological Nanoaerosols
The report describes new technologies in generation and collection of biological nanoaerosol (NA) developed
in the laboratory of Nanostructures and Nanotechnologies, ITEB RAS. NA generator to be used for
pulmonary delivery of antibiotics, anti-inflammatory and other drugs and vaccines employs a new atomization
principle based on a gas-phase neutralization of electrospray-generated drug nanoclusters with small
counter-ions produced by electrospraying of a volatile solvent like ethanol. It was demonstrated that a variety
of biological substances including proteins can be atomized into NA of 20-100 nm in size, using this
generator without affecting functional properties of the atomized substance. Several approaches have been
developed to measure doses of inhaled NA including standard condensation particle counter, quartz resonator
and filters from polyvinylpirrolidone nanofibers. It was demonstrated that water-soluble electrospun
nanofilters may also be employed to capture pathogens and pathogen biomarkers for analysis of nosocomial
infections in clinics wards, in collection of non-volatile biomarkers in the exhaled breath, in testing
working places for NA pollution and in other applications.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3543
Development of a Momentum Determined Electron Beam in the 1 -45 GeV Range
A beam line for electrons with energies in the range of 1 to 45 GeV, low
contamination of hadrons and muons and high intensity up to 10^6 per
accelerator spill at 27 GeV was setup at U70 accelerator in Protvino, Russia. A
beam tagging system based on drift chambers with 160 micron resolution was able
to measure relative electron beam momentum precisely. The resolution sigma_p p
was 0.13% at 45 GeV where multiple scattering is negligible. This test beam
setup provided the possibility to study properties of lead tungstate crystals
(PbWO_4) for the BTeV experiment at Fermilab.Comment: 12 pages, 8 figures; work done by the BTeV Electromagnetic
Calorimeter grou
Comparison of Radiation Damage in Lead Tungstate Crystals under Pion and Gamma Irradiation
Studies of the radiation hardness of lead tungstate crystals produced by the
Bogoroditsk Techno-Chemical Plant in Russia and the Shanghai Institute of
Ceramics in China have been carried out at IHEP, Protvino. The crystals were
irradiated by a 40-GeV pion beam. After full recovery, the same crystals were
irradiated using a -ray source. The dose rate profiles along
the crystal length were observed to be quite similar. We compare the effects of
the two types of radiation on the crystals light output.Comment: 10 pages, 8 figures, Latex 2e, 28.04.04 - minor grammatical change
Correlation of Beam Electron and LED Signal Losses under Irradiation and Long-term Recovery of Lead Tungstate Crystals
Radiation damage in lead tungstate crystals reduces their transparency. The
calibration that relates the amount of light detected in such crystals to
incident energy of photons or electrons is of paramount importance to
maintaining the energy resolution the detection system. We report on tests of
lead tungstate crystals, read out by photomultiplier tubes, exposed to
irradiation by monoenergetic electron or pion beams. The beam electrons
themselves were used to measure the scintillation light output, and a blue
light emitting diode (LED) was used to track variations of crystals
transparency. We report on the correlation of the LED measurement with
radiation damage by the beams and also show that it can accurately monitor the
crystals recovery from such damage.Comment: 9 pages, 6 figures, LaTeX2
LED Monitoring System for the BTeV Lead Tungstate Crystal Calorimeter Prototype
We report on the performance of a monitoring system for a prototype
calorimeter for the BTeV experiment that uses Lead Tungstate crystals coupled
with photomultiplier tubes. The tests were carried out at the 70 GeV
accelerator complex at Protvino, Russia.Comment: 12 pages, 8 figures, LaTeX2e, revised versio
Design and performance of LED calibration system prototype for the lead tungstate crystal calorimeter
A highly stable monitoring system based on blue and red light emitting diodes
coupled to a distribution network comprised of optical fibers has been
developed for an electromagnetic calorimeter that uses lead tungstate crystals
readout with photomultiplier tubes. We report of the system prototype design
and on the results of laboratory tests. Stability better than 0.1% (r.m.s.) has
been achieved during one week of prototype operation.Comment: 10 pages, 6 figures, LaTeX2
Spin alignment of mesons produced in neutron-carbon interactions
A new precise measurements of spin density matrix element of
mesons produced inclusively in neutron-carbon interactions at
\~60 GeV have been carried out in the EXCHARM experiment at the Serpukhov
accelerator. The values of obtained in the transversity frame are
for and
for . Significant
dependence of has been observed in production.Comment: 8 pages, LaTeX, 3 eps figure
Study of Radiation Damage in Lead Tungstate Crystals Using Intense High Energy Beams
We report on the effects of radiation on the light output of lead tungstate
crystals. The crystals were irradiated by pure, intense high energy electron
and hadron beams as well as by a mixture of hadrons, neutrons and gammas. The
crystals were manufactured in Bogoroditsk, Apatity (both Russia), and Shanghai
(China). These studies were carried out at the 70-GeV proton accelerator in
Protvino
Measurement of and between 3.12 and 3.72 GeV at the KEDR detector
Using the KEDR detector at the VEPP-4M collider, we have measured
the values of and at seven points of the center-of-mass
energy between 3.12 and 3.72 GeV. The total achieved accuracy is about or
better than at most of energy points with a systematic uncertainty of
about . At the moment it is the most accurate measurement of in
this energy range
- …