Prague's Emission Fourier Transform Microwave Spectrometer - Design and Preliminary Results

The design, performance and operation of the high resolution microwave spectrometer are described. The spectrometer is based on the Fabry-Perot resonator supplemented by a pulsed supersonic nozzle for adiabatic cooling of the sample. The spectrometer’s high sensitivity and resolution are demonstrated by several examples

Optimization of Transient Response Radiation of Printed Ultra Wideband Dipole Antennas (Using Particle Swarm Optimization Method)

In case of particular ultra wideband applications (i.e. radar, positioning, etc.), it is crucial to know the transient responses of antennas. In the first part of the paper, the optimization process searches for the dipole shape that accomplishes two required parameters i.e. a good matching and a minimal distortion. The particle swarm optimization method was used in the process of the dipole shape optimization. As a result, the optimized ultra wideband dipole is perfectly matched. Moreover, it minimally distorts the applied signal. The second part of the paper discusses the influence of the feeding circuit on radiating parameters and on the dipole antenna matching

Elliptic and Hyperbolic Dielectric Lens Antennas in mm-Waves

Dielectric lenses can substantially improve antenna parameters, especially the planarity of radiated waves and the antenna gain. The paper deals with their application in millimeter-wave band. The main goal concerns the introduction of characteristics and differences between the most commonly used types of dielectric lens antennas, i.e. elliptic and hyperbolic. Their particular features as well as behavior of radiating systems incorporating the lenses are investigated. Specific features of these lenses are discussed for both, near-field and farfield based on simulation and measurement results

Magnetic Field Uniformity Across the GF 9-2 YSO, L1082C Dense Core, and GF 9 Filamentary Dark Cloud

The orientation of the magnetic field (B-field) in the filamentary dark cloud GF 9 was traced from the periphery of the cloud into the L1082C dense core that contains the low-mass, low-luminosity Class 0 young stellar object (YSO) GF 9-2 (IRAS 20503+6006). This was done using SOFIA HAWC+ dust thermal emission polarimetry (TEP) at 216 um in combination with Mimir near-infrared background starlight polarimetry (BSP) conducted at H-band (1.6 um) and K-band (2.2 um). These observations were augmented with published I-band (0.77 um) BSP and Planck 850 um TEP to probe B-field orientations with offset from the YSO in a range spanning 6000 AU to 3 pc. No strong B-field orientation change with offset was found, indicating remarkable uniformity of the B-field from the cloud edge to the YSO environs. This finding disagrees with weak-field models of cloud core and YSO formation. The continuity of inferred B-field orientations for both TEP and BSP probes is strong evidence that both are sampling a common B-field that uniformly threads the cloud, core, and YSO region. Bayesian analysis of Gaia DR2 stars matched to the Mimir BSP stars finds a distance to GF 9 of 270 +/- 10 pc. No strong wavelength dependence of B-field orientation angle was found, contrary to previous claims.Comment: 18 pages, 6 figures ApJ, accepte

Air-conditioning in the cabins of passenger cars

ArticleThe objective of this paper is to analyse the current state of the constructional design and operational conditions of air - conditioning device in passenger cars. The research was focused on the function of air - conditioning equipment of passenger cars Skoda and KIA in various modes of operation during the winter, spring and summer season at different levels of air conditioning (without air - conditioning, minimum, medium and maximum level). Air temperature, air humidity, globe temperature, CO 2 concentration, dust concentration and noise inside the cabin w ere measured. Solar radiation plays a big role to rise up temperature inside the cabin. It resulted in the higher values of globe temperature than temperature of the air. The results of the measurements showed that CO 2 values were significantly lower than 2,500 ppm at minimum air - conditioning, lower than 600 ppm at medium and lower than 500 ppm at maximum level of air - conditioning. For all vehicles, dust concentration was greater when it measured with the air conditioning switched off than with the air con ditioning system turned on. The measurements confirmed that the total dust concentration was not more than 47 μg m - 3 , PM 10 lower than 28 μg m - 3 and PM 1 lower than 27 μg m - 3 . The noise levels ranged from 49.1 to 68.7 dB(A). The air - conditioning had very positive impact on the inside comfort in car cabins from all points of view during all periods of the year

Cyclopropylamine inactivation of cytochromes P450: Role of metabolic intermediate complexes

NOTICE: this is the author’s version of a work that was accepted for publication in Archives of Biochemistry and Biophysics. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Archives of Biochemistry and Biophysics, Volume 436, Issue 2, 15 April 2005 doi:10.1016/j.abb.2005.02.020The inactivation of cytochrome P450 enzymes by cyclopropylamines has been attributed to a mechanism involving initial one-electron oxidation at nitrogen followed by scission of the cyclopropane ring leading to covalent modification of the enzyme. Herein, we report that in liver microsomes N-cyclopropylbenzylamine (1) and related compounds inactivate P450 to a large extent via formation of metabolic intermediate complexes (MICs) in which a nitroso metabolite coordinates tightly to the heme iron, thereby preventing turnover. MIC formation from 1 does not occur in reconstituted P450 systems with CYP2B1/2, 2C11 or 2E1, or in microsomes exposed to gentle heating to inactivate the flavin-containing monooxygenase (FMO). In contrast, N-hydroxy-N-cyclopropylbenzylamine (3) and N-benzylhydroxylamine (4) generate MICs much faster than 1 in both reconstituted and microsomal systems. MIC formation from nitrone 5 (PhCH = N(O)cPr) is somewhat faster than from 1, but very much faster than the hydrolysis of 5 to a primary hydroxylamine. Thus the major overall route from 1 to a P450 MIC complex would appear to involve FMO oxidation to 3, further oxidation by P450 and/or FMO to nitrone 5′ (C2H4C = N(O)CH2Ph), hydrolysis to 4, and P450 oxidation to α-nitrosotoluene as the precursor to oxime 2 and the major MIC from 1