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31.
J. Młyńczak K. Kopczyński Z. Mierczyk M. Zygmunt S. Natkański M. Muzal J. Wojtanowski P. Kirwil M. Jakubaszek P. Knysak W. Piotrowski A. Zarzycka A. Gawlikowski 《Opto-Electronics Review》2013,21(3):332-337
The paper describes practical application of pulsed microchip laser generating at 1535-nm wavelength to a laser rangefinder. The complete prototype of a laser rangefinder was built and investigated in real environmental conditions. The measured performance of the device is discussed. To build the prototype of a laser rangefinder at a reasonable price and shape a number of basic considerations had to be done. These include the mechanical and optical design of a microchip laser and the opto-mechanical construction of the rangefinder. 相似文献
32.
Fluorescence amplification by electrochemically deposited silver nanowires with fractal architecture
Goldys EM Drozdowicz-Tomsia K Xie F Shtoyko T Matveeva E Gryczynski I Gryczynski Z 《Journal of the American Chemical Society》2007,129(40):12117-12122
Electrochemically deposited silver structures with nanowires 50-100 nm in diameter show high fluorescence amplification and strongly reduced fluorescence lifetimes. Both quantities depend on the structure thickness. With increasing thickness the fluorescence amplification proportionally increases and the fluorescence lifetime decreases. This thickness dependence is caused by fluorophore interaction with a system of plasmon excitations in coupled nanowires extending over micrometer size regions. Thus the amplification is attributed to a combination of extended structure area and strong plasmonic coupling between nanowires which also help to radiatively scatter the fluorescence emission. 相似文献
33.
Investigation of adsorption and vertical migration of137Cs in three kinds of soil at Lublin vicinity
S. Chibowski J. Zygmunt Z. Klimowicz 《Journal of Radioanalytical and Nuclear Chemistry》1999,242(2):287-295
The results of field, column and laboratory studies carried out on three types of mineral soils are encloses presented. Based
on the field tests, average migration rates of137Cs were calculated. The highest rate was found for the brown soil (FAO/UNESCO—Cambisol). Cesium migrated with the lowest rate
in the podzol soil (FAO/UNESCO—Cambic Podzol). The column experiments confirmed the above observation. In laboratory tests
the adsorption and desorption isotherms of Cs were determined on samples taken from 0–2 cm layers of each soil profile. It
was found from the calculated partition coefficients that Cs is always irreversibly bonded to some extent, but it appears
to be completely and irreversibly immobilized on the podzol soil. The permanent retention of cesium in the podzol soil was
also confirmed by microcalorimetric studies. The desorption energy was negligibly small and amounted to −0.21 mJ/g. In the
brown soil, containing prevailing amounts of loamy minerals, the desorption energy was found to be 106.89 mJ/g. The investigations
are supplemented by the sorption kinetics measurements. These indicate that the adsorption equilibrium is reached after a
dozen, up to twenty or so minutes. 相似文献
34.
Danuta Gorlo Bogdan Zygmunt Marta Dudek Anna Jaszek Michał Pilarczyk J. Namieśnik 《Analytical and bioanalytical chemistry》1999,363(7):696-699
Practical application of Solid-Phase Microextraction (SPME) for the assessment of the quality of indoor air is presented.
SPME was used to sample selected organic pollutants (carbon tetrachloride, benzene, toluene, chlorobenzene, p-xylene and n-decane). An SPME fiber was coated with a 100 μm film of polydimethylsiloxane. The analytes extracted were analysed with a
gas chromatograph directly coupled with a mass spectrometer (GC-MS). The method was used to assess the indoor air quality
in a few selected flats. The concentrations ranged from below detection limits to 6.9 mg/m3 for benzene depending on the flat; they were relatively high for newly built or freshly renovated flats.
Received: 14 July 1998 / Revised: 17 November 1998 / Accepted: 21 November 1998 相似文献
35.
Zygmunt Bak 《Czechoslovak Journal of Physics》1999,49(11):1525-1529
Within an analytical approach we study the RKKY interaction mediated by the electron gas, which shows fractional spectral
dimensionality. We derive formula for the RKKY exchange integral in a system of nonintegral dimensionality. Also the modifications
of magnetic interaction and magnetic moments in metallic overlayers due to the surface/interface effects are considered.
Presented at the VIII-th Symposium on Surface Physics, Třešt’ Castle, Czech Republic, June 28 – July 2, 1999. 相似文献
36.
The role of water’s H-bond percolation network in acid-assisted proton transfer was studied in water and glycerol solutions
and in sugar glasses. Proton transfer rates were determined by the fluorescence of pyrene-1-carboxylate, a compound with a
higher pK in its excited state relative to the ground state. Excitation of pyrene-1-COO− produces fluorescence from pyrene-1-COOH when a proton is accepted during the excited singlet state lifetime of pyrene-1-COO−. The presence of glycerol as an aqueous cosolvent decreases proton transfer rates from phosphoric and acetic acid in a manner
that does not follow the Stokes relationship on viscosity. In sugar glass composed of trehalose and sucrose, proton transfer
occurs when phosphate is incorporated in the glass. Sugar glass containing phosphate retains water and it is suggested that
proton transfer requires this water. The infrared (IR) frequency of water bending mode in sugar glass and in aqueous solution
is affected by the presence of phosphate and the IR spectral bands of all phosphate species in water are temperature dependent;
both results are consistent with H-bonding between water and phosphate. The fluorescence results, which studied the effect
of cosolvent, highlight the role of water in assisting proton transfer in reactions involving biological acids, and the IR
results, which give spectroscopic evidence for H-bonding between water and phosphate, are consistent with a mechanism of proton
transfer involving H-bonding. The possibility that the phosphate-rich surface of membranes assists in proton equilibration
in cells is discussed. 相似文献
37.
For the anisotropic Universe filled with massless vector field in the General Relativity frame we obtain bouncing solution for one of scale factors. We obtain the Universe with finite maximal energy density, finite value of R,RμνRμν,RμναβRμναβ and non-zero value of a scale factor for directions transverse to a vector field. Such a bounce can be also obtained for a massive vector field with kinetic initial conditions, which gives isotropic low energy limit. We discuss the existence of a bounce for a massless vector field with additional matter fields, such as cosmological constant or dust. We also discuss bouncing solution for massless vector field domination in n+2-dimensional space-time. 相似文献
38.
P. Konieczka M. Prokopowicz B. Zygmunt J. F. Biernat J. Namieśnik 《Chromatographia》2000,51(1):S249-S260
A new approach to the preparation of standard gaseous mixtures based on thermal decomposition of surface compounds, has been
reviewed. The method is used to prepare standard mixtures containing volatile analytes such as thiols, isothiocyanates, carbon
monoxide, carbon dioxide, ammonia, amines, ethylene and methyl chloride. The method enables the preparation of the standard
immediately before a calibration step. It is specially useful for the generation of standard mixtures containing volatile,
malodorous, unstable and toxic compounds.
Presented at Balaton Symposium on High Performance Separation Methods, Siófok, Hungary, September 1–3, 1999 相似文献
39.
Badral Gansukh Qiuyue Zhang Zygmunt Flisak Tongling Liang Yanping Ma Wen-Hua Sun 《应用有机金属化学》2020,34(4):e5471
The five unsymmetrical 2-[1-(2,4-dibenzhydryl-6-chlorophenylimino)ethyl]-6-[1-(arylimino)ethyl]pyridine compounds (aryl: 2,6-Me2Ph L1 , 2,6-Et2Ph L2 , 2,6-iPr2Ph L3 , 2,4,6-Me3Ph L4 and 2,6-Et2–4-MePh L5 ) were prepared and characterized with FT-IR and 1H/13C NMR spectroscopy as well as elemental analysis. The treatment of L1 – L5 with CrCl3·3THF affords the corresponding chromium chloride complexes ( Cr1 – Cr5 ) in excellent yields. The molecular structures of Cr2 and Cr3 characterized by X-ray diffraction show a distorted octahedral geometry with three nitrogen atoms and three chlorine atoms around the metal center. On activation with either MAO or MMAO, Cr1 – Cr5 collectively display high activity (up to 14.96 × 106 g (PE) mol−1 (Cr) h−1 at 60 °C) affording highly linear polyethylene with low molecular weight distribution (Mw/Mn) ranging from 1.06 to 2.81. An in-depth catalytic evaluation of Cr1 was conducted in order to investigate how the cocatalyst type and its amount, reaction temperature and polymerization time affect the catalytic activities and polymer properties. 相似文献
40.
We consider a class of algebras whose Auslander-Reiten quivers have starting components that are not generalized standard.
For these components we introduce a generalization of a slice and show that only in finitely many cases (up to isomorphism)
a slice module is a tilting module.
The first named author was supported by the Polish Scientific Grant KBN No 1 P03A 018 27 相似文献