Until now, holography experiments in the terahertz frequency range have been performed using only pulsed broadband sources and the time domain imaging technique. In this paper, we study the ...feasibility of the classical holographic technique in this spectral region using the Novosibirsk free electron laser as a high-power monochromatic terahertz source. Gabor (in-line) holograms of amplitude objects (metal masks) are recorded with the help of a temperature-sensitive phosphor image plate and a CCD camera operated in the visible range at a wavelength of 130 μm. The holograms are reconstructed by the Fresnel–Kirchhoff integral calculation in the image plane. Contrast of the images increases when several individually reconstructed holograms are summed up in a standard way. Spatial resolution of the reconstructed images amounts to 0.4 mm.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Incidence of cerebrovascular diseases (CVD) has been studied in a cohort of 12210 workers first employed at one of the main plants (reactors, radiochemical or plutonium) of the Mayak nuclear facility ...during 1948-1958 and followed up to the end of 2000. Information on external gamma doses is available for virtually all (99.9%) of these workers; the mean (+/- one standard deviation) total gamma dose was 0.91 +/- 0.95 Gy (99% percentile 3.9 Gy) for men and 0.65 +/- 0.75 Gy (99% percentile 2.99 Gy) for women. Plutonium body burden was measured only for 30.0% of workers. Amongst those monitored, the mean (+/- standard deviation) cumulative liver dose from plutonium alpha exposure was 0.40 +/- 1.15 Gy (99% percentile 5.88 Gy) for men and 0.81 +/- 4.60 Gy (99% percentile 15.95 Gy) for women 4418 cases (first diagnosis) of CVD were identified in the studied cohort. A statistically significant increasing trend in CVD incidence with total external gamma dose was revealed after adjustment for non-radiation factors and internal exposure from incorporated plutonium-239. Excess relative risk per Gy was 0.464 (95% confidence interval 0.360-0.567). Incidence of CVD was statistically significantly higher for the workers chronically exposed to external gamma rays at a dose above 1.0 Gy A statistically significant increasing trend in CVD incidence with internal liver dose from plutonium alpha exposure was observed after adjustment for non-radiation factors and external exposure. ERR per Gy was 0.155 (95% confidence interval 0.075-0.235). CVD incidence was statistically significantly higher among workers with a plutonium liver dose above 0.1 Gy, although the trend estimates differed between workers at different plants. The incidence risk estimates for external radiation are generally compatible with estimates from the study of Chernobyl clean-up workers, although the incidence data point to higher risk estimates compared to those from the Japanese A-bomb survivors.
The aza analogues of carboxylic acids chlorides containing the
NSO
2CF
3 and
NSO
2CH
3 groups instead of oxygen atom were used in the Arndt–Eistert reaction. It was found that
...N-trifluoromethylsulfonyl-(4-fluorophenyl)-carboximidoyl chloride
1 reacts with diazomethane vigorously even at −70
°C with formation of 1-trifluoromethylsulfonylamino-2-(4-fluorophenyl)-2,3-dimorpholine-4-yl-propane
3, 2-trifluoromethylsulfonylamino-2-(4-fluorobenzyl)-7-oxa-4-azonia-spiro3.5nonane
4, 2-trifluoromethylsulfonylamino-2-(4-fluorobenzyl)-1,3-dimorpholine-4-yl-propane
5 and 1-trifluoromethylsulfonylamino-2-(4-fluorobenzyl)-2,3-dimorpholine-4-yl-propane
6. Reaction of
N-methylsulfonylbenzcarboximidoyl chloride
8 with diazomethane proceeds at −15
°C yielding 4-chloro-4-methylsulfonylaminomethyl-3-phenyl-4,5-dihydro-1H-pyrazoline
9.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The analogues of carboxamides in which the sp
2-hybridized oxygen atom is replaced by more electron-withdrawing groups,
NSO
2CF
3 and
NSO
2C
4F
9, have been synthesized. The resulting
...N-perfluoroalkylsulfonyl arenecarboxamidines ArC(
NSO
2R
f)NH
2 (R
f
=
CF
3, C
4F
9) undergo an oxidative Hofmann-type rearrangement to the corresponding carbodiimides ArN
C
NSO
2R
f under the action of (diacyloxyiodo)arenes. Rearrangement of related compounds ArC(
NSO
2R)NH
2 (R
=
CH
3, Ph) containing fluorine-free substituents at the sulfonyl group also occurs in similar conditions. It was found that the reactivity of amidines rises with the increasing electron-withdrawing ability of the substituent R.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The chelates of 2-hydroxy(aminophenylnaphthyl)-azo-1-alkylbenzimidazoles were obtained from electrochemical (anodic dissolution of zero-valent d-metals) and chemical (from acetates of the same ...metals) syntheses in methanol. The EXAFS and X-ray single crystal diffraction data revealed the existence of octahedral nickel, zinc, and cadmium complexes containing four five-membered metallocycles with the N
4
О
2
or N
6
ligand environments. The formation of five-membered coordination units, non-typical for azo ligands, is explained on the basis of inner-chelate competitive metal binding of ambidentate ligand systems.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The photoluminescence of SiO
x
films deposited on
c
-Si wafers by the thermal evaporation of SiO in a vacuum and, for the first time, doped with ErF
3
by coevaporation is studied. It is shown that, ...like undoped SiO
x
films, the unannealed SiO
x
:ErF
3
films passivate the surface of the Si wafers and, thus, increase their edge photoluminescence intensity almost fivefold. A similar increase is observed after annealing of the doped films in air at 750°C. Doping with ErF
3
suppresses the photoluminescence of Si nanoclusters, if the films have been subjected to high-temperature annealing (at 750°C). In this case, the PL intensity of the band with a peak at ∼890 nm decreases as well. The ∼890 nm band is observed for the first time and, due to its features, is attributed to transitions in SiO
x
matrix defects. The experimentally observed effect of ErF
3
doping on SiO
x
film photoluminescence is interpreted. An intense photoluminescence signal from Er
3+
ions in the nearinfrared spectral region (the
4
I
11/2
→
4
I
15/2
and
4
I
13/2
→
4
I
15/2
transitions) is observed in the SiO
x
:ErF
3
films annealed in air at 750°C. This finding shows that 1.54 μm luminescent emitters, which are currently in popular demand, can be produced by a simple low-cost method.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The CERN RD39 Collaboration is developing super-radiation hard cryogenic Si detectors for applications in experiments of the LHC and the future LHC Upgrade. Radiation hardness up to the fluence of 10
...16
n
eq/cm
2 is required in the future experiments. Significant improvement in the radiation hardness of silicon sensors has taken place during the past years. However, 10
16
n
eq/cm
2 is well beyond the radiation tolerance of even the most advanced semiconductor detectors made by commonly adopted technologies. Furthermore, at this radiation load the carrier trapping will limit the charge collection depth to the range of 20–30
μm regardless of the depletion depth. The key of our approach is freezing the trapping that affects Charge Collection Efficiency (CCE).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This paper considers the problem of an interface for educational platform, which is fully effective for achieving the outcomes of educational activity. The current research is a theoretical analysis ...of existing recommendations on UI/UX design, applied when creating educational systems, as well as of research papers that study user interface (UI) usability and evaluate user experience (UX) in designing on-line platforms. This article describes a mechanism for evaluating usability with the help of baseline and final evaluation tool. It also studies UX components, that ensure its high quality. A list of standard components of web-design is being discussed in the present paper; modern trends in web-design of educational platforms are identified. The paper provides the description of an on-line course model, which is built on the basis of analysis of the prerequisites for existing and functioning of educational on-line systems and which is aimed at achieving outcomes of educational activity. There is ground to believe that the design of educational on-line courses will contribute to achieving the outcomes of educational activity, if user interface components comply with a list of criteria, such as easy-to-perceive content, no extra information, easy and simple navigation on the pages of the course, following the principles of usability.
The mechanisms of the laser-stimulated diffusion of indium in CdTe have been studied. The structures of a thin In film on the CdTe substrate were irradiated by nanosecond pulses of ruby, KrF excimer ...and Nd：YAG lasers. It is established that the dominanting mechanism of In diffusion in CdTe at solid-phase （before CdTe melting） doping is baro-diffusion. The diffusion coefficient and average drift velocity of indium are determined. The temperature dynamics and kinetics of laser-induced phase transitions are studied by numerical simulation on the basis of Stefan problem.
