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Małgorzata Murat, Iwona Malinowska, Holger Hoffmann and Piotr Baranowski

Abstract

Meteorological time series are used in modelling agrophysical processes of the soil-plant-atmosphere system which determine plant growth and yield. Additionally, long-term meteorological series are used in climate change scenarios. Such studies often require forecasting or projection of meteorological variables, eg the projection of occurrence of the extreme events. The aim of the article was to determine the most suitable exponential smoothing models to generate forecast using data on air temperature, wind speed, and precipitation time series in Jokioinen (Finland), Dikopshof (Germany), Lleida (Spain), and Lublin (Poland). These series exhibit regular additive seasonality or non-seasonality without any trend, which is confirmed by their autocorrelation functions and partial autocorrelation functions. The most suitable models were indicated by the smallest mean absolute error and the smallest root mean squared error.

Open access

J.A. Schmidt

Abstract

Since 1960 the blue mould disease caused by Peronospora tabacina Adam (PtA) and which leads to considerable losses, has been occurring epidemically in tobacco grown in Europe and parts of Asia and Africa. All varieties cultivated are susceptible to this fungus, which is an inevitable tobacco parasite, and must either be protected prophylactically by weekly spraying with dithiocarbamate, which leaves residues, or be replaced by new, PtA-resistant strains based on wild forms of Nicotiana. In investigations of our own - published in 5 parts in the "Zeitschrift fuer Naturforschung" - the fundaments of a third way of combatting this disease were worked out using the very PtA-susceptible German, high-quality strains "Badischer Geudertheimer'', ''Badischer Burley E'' and "Virgin SCR''. This present paper contains, summarized, the state of this work at the end of 1971. It was observed that the PtA-resistant hybrid strains (U. S. Bel.-61 types) were also infected by PtA, but this infection was stopped by the synthesis of antibodies, and that there are reciprocal effects of the substances triggering off resistance and microorganisms. The antibodies were separated out electrophoretically, established chemically and ascertained to be nucleoproteid or nucleotides, and to be an alloxazin compound closely related to vitamin B2. Their delivery, via the roots, to the cotyledons of the said German high-quality strains produced in them, during the 2-month observation period possible, absolute resistance to Peronospora, with no external change in the varieties. The observation results and the methods for separating the substances triggering off resistance are shown in two stages of development, and the results discussed. Within the scope of the interreaction with other microorganisms a special bacteria was discovered which made it possible to also identify the substances which trigger off PtA-resistance in the commercial Difco yeast extract, and to separate them out. After delivery of these separated substances to the cotyledons of the said German varieties, the same positive resistance-triggering results were ascertained. These substances, originating from yeast extract, were compared chromatographically with those extracted from the Bel. varieties and proved to be chemically equivalent. All these results were secured over a period of several years. A curative effect which lasted up to 48 hours after PtA infection, was established. These results with the special bacteria are given in a later stage of development. This special bacteria (Micrococcus spec.) considerably accelerated the operations, which, for technical plant protection reasons, are possible only up to 5 months a year. In a first field trial in 1971, and once Peronospora had occurred naturally, the resistance behaviour of var. ''Badischer Geudertheimer'', after a single prior treatment of the cotyledons was observed throughout the whole of the tobacco crop. The results and their scientific fundaments are discussed and their possible uses, also within the scope of pollution control, are listed

Open access

H. Elmenhorst

Abstract

The purpose of this work was to compare the composition of the semi-volatile fraction of the smoke of different tobacco types. A German blend cigarette without any additive and further three cigarettes made from Virginia, Burley and Oriental tobaccos were compared. The composition of the acidic fraction of the "semi-volatiles" of the smoke was analysed. 22 substances including the newly identified octadeca-9,12,15-trien-1-ol were identified by GC and mass spectrometry and quantitatively determined by GC-methods. Although in general all the smoke samples were qualitatively similar in volatile acid and phenol composition, there were, quantitatively, remarkable differences between the different tobacco types. In the semi-volatile fraction of the smoke of the Oriental cigarette, the level of 3-methylvaleric acid and isovaleric acid was highly increased. The semi-volatile fraction of the smoke of the Virginia cigarette showed an overall increased level for the rest of the aliphatic acids which we analysed. Especially the amount of palmitic acid is increased. Phenol, cresol, catechol, guajacol and benzoic acid were also increased compared with the Burley and Oriental cigarettes. In the semi-volatile fraction of Burley smoke all analysed substances were diminished

Open access

Pradyuman Barnwal, Ashish M. Mohite, Krishna K. Singh and Pankaj Kumar

Abstract

In this communication, selected physicomechanical characteristics of ground turmeric (cv. Prabha) were investigated for cryogenic and ambient grinding conditions of turmeric at different moisture contents (4, 6, 8 and 10% w.b.). A cryogenic grinder (Model: 100 UPZ, Hosokawa Alpine, Germany) and a micro pulverizer (hammer mill) were used for cryogenic and ambient grinding, respectively. The ground turmeric was graded in three grades viz. Gr-I, Gr-II and Gr-III with a sieve shaker using BSS Nos. 40, 85 and pan, respectively. Tap densities for cryogenic and ambient ground turmeric decreased from 678.7 (Gr-I) to 546.7 kgm-3 (Gr-III) and from 642.3 (Gr-I) to 468.6 kgm-3 (Gr-III), respectively, with the moisture increase. The angle of repose for cryogenic and ambient ground turmeric increased linearly from 26.85 (Gr-I) to 34.0° (Gr-III) and from 23.10 (Gr-I) to 28.06° (Gr-III), respectively with the increase in moisture content. The static coefficient of friction was the highest on plywood surface followed by mild steel sheet and galvanized iron sheet. The cryoground samples were found better in colour. Thermal conductivity of cryo-ground samples was higher than that of ambient ground samples. These physico-mechanical characteristics of cryogenic and ambient ground turmeric will be helpful for packaging, handling, and storage.

Open access

Lea Reger, Julia Moß, Harald Hahn and Jürgen Hahn

Summary

Although smoking is responsible for a huge variety of diseases which result in ~16% of the fatalities in the United States and Europe respectively, cigarettes are still being sold far and wide. Mentholated cigarettes were introduced in 1920, since then to today social recognition and the use of flavored tobacco products is still increasing especially within young people. The EU adopted as its measure to reduce tobacco use among adolescents the prohibition of tobacco products with a characteristic flavor by means of the directive 2014/40/EU of the European Parliament and the Council.

For this reason, we developed a method for the simultaneous determination of 14 tobacco flavors like menthol, menthol-like and other compounds via gas-chromatography coupled with mass-spectrometry (GC/MS) and analyzed 21 different tobacco products (mentholated and non-mentholated cigarettes, as well as electrically heated tobacco products (EHTPs)) of the German market regarding their flavoring compound patterns. The highest amounts of flavoring compounds were determined in menthol cigarettes (~10,000 μg/stick) whereas non-mentholated cigarettes and EHTPs featured only ~10 μg/stick. In total, seven flavoring compounds like menthol, L-menthone, L-linalool, isopulegol, geraniol, camphor and WS-3 (cooling agent) were available within the samples. Mentholated cigarettes could be clearly identified since > 99% of the measured flavoring compounds was represented by menthol. Although flavoring compounds in non-mentholated cigarettes and EHTPs were quite comparable, they could be differentiated due to different flavoring compound patterns. Brandspecific flavoring compound patterns were not recognized.

Open access

Magdalena Orszulik, Adam Fic and Tomasz Bury

Abstract

This study deals with numerical modeling of passive autocatalytic hydrogen recombiners (PARs). Such devices are installed within containments of many nuclear reactors in order to remove hydrogen and convert it to steam. The main purpose of this work is to develop a numerical model of passive autocatalytic recombiner (PAR) using the commercial computational fluid dynamics (CFD) software ANSYS-FLUENT and tuning the model using experimental results. The REKO 3 experiment was used for this purpose. Experiment was made in the Institute for Safety Research and Reactor Technology in Julich (Germany). It has been performed for different hydrogen concentrations, different flow rates, the presence of steam, and different initial temperatures of the inlet mixture. The model of this experimental recombiner was elaborated within the framework of this work. The influence of mesh, gas thermal conductivity coefficient, mass diffusivity coefficients, and turbulence model was investigated. The best results with a good agreement with REKO 3 data were received for k-ɛ model of turbulence, gas thermal conductivity dependent on the temperature and mass diffusivity coefficients taken from CHEMKIN program. The validated model of the PAR was next implemented into simple two-dimensional simulations of hydrogen behavior within a subcompartment of a containment building.

Open access

Thomas Sajeev, Mohamed Mustafa and Sanjay Supe

Dosimetrical evaluation of Leksell Gamma Knife 4C radiosurgery unit

A number of experiments was performed using standard protocols, in order to evaluate the dosimetric accuracy of Leksell Gamma Knife 4C unit. Verification of the beam alignment has been performed for all collimators using solid plastic head phantom and Gafchromic™ type MD-55 films. The study showed a good agreement of Leksell Gammaplan calculated dose profiles with experimentally determined profiles in all three axes. Isocentric accuracy is verified using a specially machined cylindrical aluminium film holder tool made with very narrow geometric tolerances aligned between trunnions of 4 mm collimator. Considering all uncertainties in all three dimensions, the estimated accuracy of the unit was 0.1 mm. Dose rate at the centre point of the unit has been determined according to the IAEA, TRS-398 protocol, using Unidose-E (PTW-Freiburg, Germany) with a 0.125 cc ion chamber, over a period of 6 years. The study showed that the Leksell Gamma Knife 4C unit is excellent radiosurgical equipment with high accuracy and precision, which makes it possible to deliver larger doses of radiation, within the limits defined by national and international guidelines, applicable for stereotactic radiosurgery procedures.

Open access

Michał Półtorak, Edyta Fujak and Paweł Kukołowicz

Abstract

The aim of the study was to investigate the influence of thermoplastic masks material (Klarity Medical&Equipment Co., Guangzhou, China) with different diameters of holes (ϕ 0.25 cm and ϕ 0.40 cm) on the dose distribution in the build-up region for photon beams. Measurements were made for external radiation beams produced by the linear accelerator (TrueBeam, Varian Medical Systems, Inc., Palo Alto, CA, USA) using the Markus parallel plane ionization chamber and the Unidos electrometer (both from PTW, Freiburg, Germany). Measurements were made in a solid water phantom for two photon energies 6 MV and 15 MV, at 90 cm source to skin distance, for four fields of 5 cm × 5 cm, 10 cm × 10 cm, 15 cm × 15 cm and 20 cm × 20 cm. Compared to the open field, the maximum dose with mask was closer to the surface of the phantom by about 1.4 mm and 1.2 mm for 6 MV and 15 MV X-Rays, respectively. The surface dose increase from 10% to 42% for 6 MV and from 5% to 28% for 15 MV X-Rays.

Open access

Natalia Krawczyk, Jacek Kaczmarczyk, Monika Kubkowska and Leszek Ryć

Abstract

The paper presents comparison of two silicon drift detectors (SDD), one made by Amptek, USA, and the second one by PNDetector, Germany, which are considered for a soft X-ray diagnostic system for W7-X. The sensitive area of the first one is 7 mm2 × 450 μm and the second one is 10 mm2 × 450 μm. The first detector is cooled by a double-stage Peltier element, while the second detector is cooled by single-stage Peltier element. Each one is equipped with a field-effect transistor (FET). In the detector from Amptek, the FET is mounted separately, while in the detector from PNDetector, the FET is integrated on the chip. The nominal energy resolution given by the producers of the first and the second one is 136 eV@5.9 keV (at -50°C) and 132 eV@5.9 keV (at -20°C), respectively. Owing to many advantages, the investigated detectors are good candidates for soft X-ray measurements in magnetic confinement devices. They are suitable for soft X-ray diagnostics, like the pulse height analysis (PHA) system for the stellarator Wendelstein 7-X, which has been developed and manufactured at the Institute of Plasma Physics and Laser Microfusion (IPPLM), Warsaw, in collaboration with the Max Planck Institute for Plasma Physics (IPP), Greifswald. The diagnostic is important for the measurements of plasma electron temperature, impurities content, and possible suprathermal tails in the spectra. In order to choose the best type of detector, analysis of technical parameters and laboratory tests were done. Detailed studies show that the most suitable detector for the PHA diagnostics is the PNDetector.

Open access

Yashashri Patil, S. Khirwadkar, S. M. Belsare, Rajamannar Swamy, M. S. Khan, S. Tripathi and K. Bhope

Abstract

This paper is focused on various aspects of the development and testing of water cooled divertor PFCs. Divertor PFCs are mainly designed to absorb the heat and particle fluxes outflowing from the core plasma of fusion devices like ITER. The Divertor and First Wall Technology Development Division at the Institute for Plasma Research (IPR), India, is extensively working on development and testing of divertor plasma facing components (PFCs). Tungsten and graphite macro-brush type test mock-ups were produced using vacuum brazing furnace technique and tungsten monoblock type of test mock-ups were obtained by hot radial pressing (HRP) technique. Heat transfer performance of the developed test mock-ups was tested using high heat flux tests with different heat load conditions as well as the surface temperature monitoring using transient infrared thermography technique. Recently we have established the High Heat Flux Test Facility (HHFTF) at IPR with an electron gun EH300V (M/s Von Ardenne Anlagentechnik GmbH, Germany) having maximum power 200 kW. Two tungsten monoblock type test mock-ups were probed using HHFTF. Both of the test mock-ups successfully sustained 316 thermal cycles during high heat flux (HHF) tests. The test mock-ups were non-destructively tested using infrared thermography before and after the HHF tests. In this note we describe the detailed procedure used for testing macro-brush and monoblock type test mock-ups using in-house transient infrared thermography set-up. An acceptance criteria limit was defined for small scale macro-brush type of mock-ups using DTrefmax value and the surface temperature measured during the HHF tests. It is concluded that the heat transfer behavior of a plasma facing component was checked by the HHF tests followed by transient IR thermography. The acceptance criteria DTrefmax limit for a graphite macro-brush mock-up was found to be ~3°C while for a tungsten macro-brush mock-up it was ~5°C.