Stark broadening data for spectral lines of rare-earth elements: Nb III

The electron-impact widths for 15 doubly charged Nb ion lines have been theoretically determined by using the modified semiempirical method. Using the obtained results, we considered the influence of the electron-impact mechanism on line shapes in spectra of chemically peculiar stars and white dwarfs.Comment: 10 pages, 2 figures, 1 table, accepted in Advances in Space Researc

Piezoresistant probe for measurement of velocity in one-dimensional incompressible flow

Radeći na problemu kalibracije sondi sa zagrejanim vlaknima u okviru rada [3], javila se potreba za sondom kojom se može meriti trenutna brzina u jednodimenzijskom vazdušnom mlazu. Ubrzo potom na Mašinskom fakultetu u Beogradu je razrađena ideja o prvoj domaćoj piezorezistivnoj sondi kojom se meri trenutni diferencijalni pritisak. Sonda je realizovana u saradnji sa IHTM, Centrom za mikroelektronske tehnologije i monokristale. Probna ispitivanja su pokazala da se sonda može uspešno koristiti za merenje trenutne brzine jednodimenzijskog nestišljivog strujanja. U tom smislu je posle prvenac sonde napravljeno još nekoliko sličnih sondi. U radu su dati osnovni elementi tehnološkog postupka za dobijanje senzora pritiska. Pored detaljnog opisa senzorskog čipa ovde su prikazani i drugi elementi sonde JR-p. Pre svakog merenja sondom ona mora da se baždari. Sonda JR-p se baždari statički i u kvazistacionarnom vazdušnom mlazu. Ovde su prikazani rezultati jednog takvog baždarenja.Working on the problem of calibration of hot wire probes within (3), we came to the need to have a probe for measuring the instantaneous velocity in a one-dimensional air jet. Soon after the idea concerned with the first domestic piezoresistant probe by means of which the instantaneous differential pressure can be measured was developed on the Faculty of Mechanical Engineering. The probe was realized in the collaboration with IHTM, the Center for microelectronic technology and monocrystals. First tests with the probe showed that it could be successfully used for measuring the instantaneous velocity in one-dimensional incompressible flows. In that sense, some more similar probes were produced after the pioneering one. In this paper the basic elements of the technological procedure for the production of the pressure sensor are given. In addition to a detailed description of the sensor chip we show here some other elements of the probe JR-p also. Before any use the probe must be calibrated. The probe JR-p is calibrated statically in a quasi-steady air jet. The results of such a calibration are presented here

Piezoresistant probe for measurement of velocity in one-dimensional incompressible flow

Radeći na problemu kalibracije sondi sa zagrejanim vlaknima u okviru rada [3], javila se potreba za sondom kojom se može meriti trenutna brzina u jednodimenzijskom vazdušnom mlazu. Ubrzo potom na Mašinskom fakultetu u Beogradu je razrađena ideja o prvoj domaćoj piezorezistivnoj sondi kojom se meri trenutni diferencijalni pritisak. Sonda je realizovana u saradnji sa IHTM, Centrom za mikroelektronske tehnologije i monokristale. Probna ispitivanja su pokazala da se sonda može uspešno koristiti za merenje trenutne brzine jednodimenzijskog nestišljivog strujanja. U tom smislu je posle prvenac sonde napravljeno još nekoliko sličnih sondi. U radu su dati osnovni elementi tehnološkog postupka za dobijanje senzora pritiska. Pored detaljnog opisa senzorskog čipa ovde su prikazani i drugi elementi sonde JR-p. Pre svakog merenja sondom ona mora da se baždari. Sonda JR-p se baždari statički i u kvazistacionarnom vazdušnom mlazu. Ovde su prikazani rezultati jednog takvog baždarenja.Working on the problem of calibration of hot wire probes within (3), we came to the need to have a probe for measuring the instantaneous velocity in a one-dimensional air jet. Soon after the idea concerned with the first domestic piezoresistant probe by means of which the instantaneous differential pressure can be measured was developed on the Faculty of Mechanical Engineering. The probe was realized in the collaboration with IHTM, the Center for microelectronic technology and monocrystals. First tests with the probe showed that it could be successfully used for measuring the instantaneous velocity in one-dimensional incompressible flows. In that sense, some more similar probes were produced after the pioneering one. In this paper the basic elements of the technological procedure for the production of the pressure sensor are given. In addition to a detailed description of the sensor chip we show here some other elements of the probe JR-p also. Before any use the probe must be calibrated. The probe JR-p is calibrated statically in a quasi-steady air jet. The results of such a calibration are presented here

The shape of Fe Kα\alpha line emitted from relativistic accretion disc around AGN black holes

The relativistically broadened Fe K$\alpha$ line, originating from the accretion disc in a vicinity of a super massive black hole, is observed in only less than 50\% of type 1 Active Galactic Nuclei (AGN). In this study we investigate could this lack of detections be explained by the effects of certain parameters of the accretion disc and black hole, such as the inclination, the inner and outer radius of disc and emissivity index. In order to determine how these parameters affect the Fe K $\alpha$ line shape, we simulated about 60,000 Fe K $\alpha$ line profiles emitted from the relativistic disc. Based on simulated line profiles, we conclude that the lack of the Fe K$\alpha$ line detection in type 1 AGN could, be caused by the specific emitting disc parameters, but also by the limits in the spectral resolution and sensitivity of the X-ray detectors.Comment: Based on the talk presented Balkan Workshop BW2018 (10-14 June 2018, Ni\v{s}, Serbia), accepted for publishing in International Journal of Modern Physics A, 8 figures, 1 table, 15 page

Market and performance implications of fast fit service concepts in automotive maintenance systems

This paper presents research related to fast fit service concepts in the automotive maintenance at authorized services, as tool usefull that service provider increase competitiveness. Implementation process of fast fit maintenance service concept in two authorized service networks is shown as well as the results of its empirical implementation, by using descriptive, comparative and statistical analysis method. Implementation of new maintenance service approach shows that its application leads to an improve of the after-sales work performances, relevantly affects the result of the whole business. In particular, in relation to the period when this service concept was not implemented new approach resulted in an increase in the number of total service visits. This research is limited to the automotive maintenance service industry especially as place for an improvement in authorized workshops. But some further studies could refine those measures and process of implementation for the applicability in some other service context

Mercuration of Some Aliphatic Aldehydes. The Crystal Structure of 2,2-Bis(chloromercuri)butyraldehyde

Tris ( chloromercuri)acetaldehyde (1), 2,2-bis( chloromercuri)propionaldehyde (II) and 2,2-bis(chloromercuri)butyraldehyde (III) were obtained by mercuration of the corresponding aldehyde in an aqueous mercury(II) chloride solution containing sodium acetate. The mercurated aldehydes (II) and (III) are described for the first time. The crystal structure of (III) was determined by means of Patterson and Fourier syntheses based on threedimensional X-ray diffractometer intensity data and refined by the full-matrix least- squares method to an R value of 0.049. Crystals are orthorhombic, space group Pna21 with z = 4 formula units in the unit cell of the dimensions : a= 1114.6(6), b = 1121.3(5), c = 657.3(3) pm, Dots= 4.51and Deale = 4.38 Mg m-3• The structure consists of discrete moleculesof 2,2-bis(chloromercuri)butyraldehyde. The Hg-C bond lengthsare 216(2) and 209(2) pm. The Hg-C-Hg bond angle is 103(1) 0 and the C-Hg-Cl bond angles are 173(2)0 and 172(2)0 , respectively

Management of joint-stock companies and farms by using fair value of agricultural equipment in financial statements on the example of IMT 533 tractor

More demanding management requires management to foster the application of different mechanisms. One of the upcoming ways of improving management is the use of the fair value of property and equipment in the business books of the company. The authors of this study emphasize the importance of fair valuation of agricultural equipment, processing surveyed 382 legal entities of the Republic of Serbia, in the case of widespread tractor IMT 533 agricultural holdings in 207 and 175 joint-stock companies. To show the real application of fair value, the research period lasted from 2015 to 2018. We came to the basic conclusion that there is a statistically significant relationship between organizations, enterprises and the age of the tractor to the application of the fair value of the tractor in the business books of the company. There is also a conclusion that fair financial reporting brings about benefits to agricultural entities of other legal forms

Cardiopulmonary assessment of patients diagnosed with Gaucher’s disease type I

Background: Understanding the basis of the phenotypic variation in Gaucher's disease (GD) has proven to be challenging for efficient treatment. The current study examined cardiopulmonary characteristics of patients with GD type 1. Methods: Twenty Caucasian subjects (8/20 female) with diagnosed GD type I (GD-S) and 20 age- and sex-matched healthy controls (C), were assessed (mean age GD-S: 32.6 ± 13.1 vs. C: 36.2 ± 10.6, p >.05) before the initiation of treatment. Standard echocardiography at rest was used to assess left ventricular ejection fraction (LVEF) and pulmonary artery systolic pressure (PASP). Cardiopulmonary exercise testing (CPET) was performed on a recumbent ergometer using a ramp protocol. Results: LVEF was similar in both groups (GD-S: 65.1 ± 5.2% vs. C: 65.2 ± 5.2%, p >.05), as well as PAPS (24.1 ± 4.2 mmHg vs. C: 25.5 ± 1.3 mmHg, p >.05). GD-S had lower weight (p <.05) and worse CPET responses compared to C, including peak values of heart rate, oxygen consumption, carbondioxide production (VCO2), end-tidal pressure of CO2, and O2 pulse, as well as HR reserve after 3 min of recovery and the minute ventilation/VCO2 slope. Conclusions: Patients with GD type I have an abnormal CPET response compared to healthy controls likely due to the complex pathophysiologic process in GD that impacts multiple systems integral to the physiologic response to exercise

Analysis of Comfort Parameters in Special Purpose Vehicles from Technological Development Point of View

The analysis of comfort parameters in the crew cabin space of two variants of the special purpose off-road vehicle is presented, taking technological development aspects into account. Tests of noise, vibration and heating - cooling efficiency have been performed in realistic operating conditions, during the intensive driving on three selected test tracks, in order to ensure the repeatability of the obtained results. Measuring of noise and vibration levels at the drivers, co-drivers and crew members' seats were performed at strictly defined vehicle speed. Heating efficiency tests for the cabin have been performed in laboratory conditions, inside a cold chamber with the constant temperature of (-16 degrees C), whereas cooling efficiency tests were conducted in the hot chamber at the temperature of (+ 40 degrees C). The results of these tests enable the selection of a more comfortable variant of vehicle, wherein the one with less seats for passengers in the cabin which, in addition to more comfort also has the advantage of greater storage space, and from the application flexibility standpoint, which is offered by the possibility of transporting more passengers and less load, such vehicles offer better environment control from within the vehicle

Juvenilni polip kod odraslih osoba

Colorectal juvenile polyp as a pathologic entity was first described by Verse. These non-neoplastic lesions are most commonly found in children and infants, while in older children after the age of 14 and adults are a rare phenomenon. A 75-year-old female underwent colonoscopy. There was a pedunculated polyp in the transverse colon. Complete endoscopic electroresection of this polyp was performed and the polyp was sent for histopathologic analysis. Macroscopically, the polyp was described as a fragment of irregular round shape, size of about 2.5x2x1 cm, with fine-grained, reddish surface, showing dark red color on serial sections. Histologic examination of the polyp showed some irregularly distributed glands, some of which were cystically dilated. All glandular formations were coated with normal intestinal epithelium. The surface of the polyp was partially eroded and replaced by non-specific cellular granulation tissue. There were some signs of hemorrhagic infarction in the stroma of the polyp. Histopathologic examination indicated that histopathologic characteristics of this polyp corresponded to juvenile polyp. Juvenile polyps are very rarely found in adults. Therefore, we describe a case of this patient in her eighties with juvenile polyp localized in the transverse colon.Kolorektalni juvenilni polip kao patološki entitet prvi opisuje Verse. Ove ne-neoplastične lezije najčešće susrećemo kod djece i dojenčadi, dok kod starije djece i odraslih poslije 14. godine života predstavljaju rijetku pojavu. Osobi ženskoga spola u dobi od 75 godina napravljena je kolonoskopija. Na transverzalnom dijelu kolona nađen je pedunkularni polip. Načinjena je kompletna endoskopska elektroresekcija polipa, a polip poslan na patohistološku analizu. Polip je makroskopski opisan kao nepravilan okruglasti fragment dimenzija oko 2,5x2x1 cm, sitnozrnate, crvenkaste površine, koji je na serijskim rezovima tamno-crvene boje. Histološkim pregledom u polipu su nađene i opisane nepravilno raspoređene žljezdane formacije cističnog izgleda od kojih su pojedine dilatirane. Sve žljezdane formacije su obložene pravilnim epitelom intestinalnog tipa, a površina polipa je dijelom erodirana i zamijenjena staničnim nespecifičnim granulacijskim tkivom. U stromi polipa se uočavaju znaci hemoragijskog infarkta. Patohistološki nalaz pokazao je da polip po svojim patohistološkim karakteristikama odgovara juvenilnom polipu. Pojava juvenilnih polipa kod odraslih predstavlja jako rijetku pojavu i zbog toga opisujemo ovaj slučaj bolesnice s juvenilnim polipom otkrivenim u osmom desetljeću života s lokalizacijom na transverzalnom kolonu