Surface charging of thick porous water ice layers relevant for ion sputtering experiments

We use a laboratory facility to study the sputtering properties of centimeter-thick porous water ice subjected to the bombardment of ions and electrons to better understand the formation of exospheres of the icy moons of Jupiter. Our ice samples are as similar as possible to the expected moon surfaces but surface charging of the samples during ion irradiation may distort the experimental results. We therefore monitor the time scales for charging and dis- charging of the samples when subjected to a beam of ions. These experiments allow us to derive an electric conductivity of deep porous ice layers. The results imply that electron irradiation and sputtering play a non-negligible role for certain plasma conditions at the icy moons of Jupiter. The observed ion sputtering yields from our ice samples are similar to previous experiments where compact ice films were sputtered off a micro-balance.Comment: arXiv admin note: text overlap with arXiv:1509.0400

A miniature mass analyser for in-situ elemental analysis of planetary material-performance studies

The performance of a laser ablation mass analyser designed for in-situ exploration of the chemical composition of planetary surfaces has been investigated. The instrument measures the elemental and isotopic composition of raw solid materials with high spatial resolution. The initial studies were performed on NIST standard materials using IR laser irradiance (< 1 GW cm−2) at which a high temporal stability of ion formation and sufficiently low sample consumption was achieved. Measurements of highly averaged spectra could be performed with typical mass resolution of m/Δm ≈ 600 in an effective dynamic range spanning seven decades. Sensitive detection of several trace elements can be achieved at the ~ ppm level and lower. The isotopic composition is usually reproduced with 1% accuracy, implying good performance of the instrument for quantitative analysis of the isotopic fractionation effects caused by natural processes. Using the IR laser, significant elemental fractionation effects were observed for light elements and elements with a high ionization potential. Several diatomic clusters of major and minor elements could also be measured, and sometimes these interfere with the detection of trace elements at the same nominal mass. The potential of the mass analyser for application to sensitive detection of elements and their isotopes in realistic samples is exemplified by measurements of minerals. The high resolution and large dynamic range of the spectra makes detection limits of ~100ppb possible. Figure The mass spectrum of Allende meteorite measured by a miniature laser ablation mass spectrometer. Similar mass spectra of planetary materials in-situ could be measured with spatial resolution of 10-100 μm (white circles) providing means for chemical analysis of planetary surface

Optical diagnostics of diesel spray injections and combustion in a high-pressure high-temperature cell

We report on spatially and temporally resolved optical diagnostic measurements of propagation and combustion of diesel sprays introduced through a single-hole fuel injector into a constant volume, high-temperature, high-pressure cell. From shadowgraphy images in non-reacting environments of pure nitrogen, penetration lengths and dispersion angles were determined for non-vaporizing and vaporizing conditions, and found to be in reasonable agreement with standard models for liquid jet propagation and break-up. Quasi-simultaneous two-dimensional images were obtained of laser elastic light scattering, shadowgraphs and spectrally integrated flame emission in a reacting environment (cell temperature 850 K). In addition laser-induced incandescence was employed for the identification of soot-loaded regions. The simultaneously recorded spray images exhibit remarkable structural similarity and provide complementary information about the spray propagation and combustion process. The measurements also reveal the fuel vapor cloud extending well beyond the liquid core and close to the nozzle tip. Ignition takes place close to the tip of the spray within the mixing layer of fuel vapor and surrounding air. Soot is formed in the vapor core region at the tip of the liquid fuel jet. Our results support recently developed phenomenological model on diesel spray combustio

Studies of Diffuse Interstellar Bands. V. Pairwise Correlations of Eight Strong DIBs and Neutral Hydrogen, Molecular Hydrogen, and Color Excess

We establish correlations between equivalent widths of eight diffuse interstellar bands (DIBs), and examine their correlations with atomic hydrogen, molecular hydrogen, and EB-V . The DIBs are centered at \lambda\lambda 5780.5, 6204.5, 6283.8, 6196.0, 6613.6, 5705.1, 5797.1, and 5487.7, in decreasing order of Pearson\^as correlation coefficient with N(H) (here defined as the column density of neutral hydrogen), ranging from 0.96 to 0.82. We find the equivalent width of \lambda 5780.5 is better correlated with column densities of H than with E(B-V) or H2, confirming earlier results based on smaller datasets. We show the same is true for six of the seven other DIBs presented here. Despite this similarity, the eight strong DIBs chosen are not well enough correlated with each other to suggest they come from the same carrier. We further conclude that these eight DIBs are more likely to be associated with H than with H2, and hence are not preferentially located in the densest, most UV shielded parts of interstellar clouds. We suggest they arise from different molecules found in diffuse H regions with very little H (molecular fraction f<0.01). Of the 133 stars with available data in our study, there are three with significantly weaker \lambda 5780.5 than our mean H-5780.5 relationship, all of which are in regions of high radiation fields, as previously noted by Herbig. The correlations will be useful in deriving interstellar parameters when direct methods are not available. For instance, with care, the value of N(H) can be derived from W{\lambda}(5780.5).Comment: Accepted for publication in The Astrophysical Journal; 37 pages, 11 figures, 6 table

Dzieło Świętego Jakuba Apostoła

Utworzone w maju 1948 r. Państwo Izrael określiło nowe ramy prawne dla Kościołów znajdujących się na jego terytorium. W Deklaracji Niepodległości zagwarantowano wolność wyznania i kultu dla wszystkich obywateli. Jednakże od samego początku pojawił się problem w odniesieniu do Żydów, którzy przeszli na chrześcijaństwo, a których należało objąć opieką duszpasterską, posługując się w tym celu także w liturgii językiem hebrajskim. Wśród pionierów znaleźli się ojcowie: Jean-Roger Héné AA, Joseph Stiassny NCD i Bruno Hussar OP. Pewna niechęć ze strony duchowieństwa arabskiego i europejskiego została przezwyciężona poparciem ze strony zarówno miejscowej hierarchii, jak i watykańskiej. 11 lutego 1955 r. Dzieło Świętego Jakuba zostało zatwierdzone ad experimentum ad annum, a po roku próby 11 lutego 1956 r. Patriarcha zatwierdził jego statuty. Pionierzy Dzieła widzieli w tym wydarzeniu powrót do początku, kiedy to pierwszą kościelną wspólnotą była jerozolimska gmina judeochrześcijańska. Ta próba odtworzenia Kościoła początków miałaby przywrócić element hebrajski utracony w historycznym rozwoju Kościoła. Zagadnieniem do rozstrzygnięcia pozostaje jego kształt i sposób realizacji

Dzieło Świętego Jakuba Apostoła: Powstanie Kościoła języka hebrajskiego w Łacińskim Patriarchacie Jerozolimy

The State of Israel, established in May 1948, defined a new legal framework for the Churches located on its territory. The Declaration of Independence guaranteed freedom of religion and worship for all citizens. From the very beginning, however, there was a problem with regard to the Jews who had converted to Christianity and who had to be given pastoral care, also using Hebrew in the liturgy. Among the pioneers were Fathers Jean-Roger Héné AA, Joseph Stiassny NCD and Bruno Hussar OP. A certain reluctance on the part of the Arab and European clergy was overcome by the support from both the local hierarchy and the Vatican. On 11th February 1955, the Work of St. James was approved ad experimentum ad annum, and after a year of probation, on 11th February 1956, the Patriarch approved its statutes. The pioneers of the Work saw in this event a return to the beginning, when the first ecclesial community was the Judeo-Christian community in Jerusalem. This attempt to reconstruct the early Church was intended to restore the Hebrew element lost in the historical development of the Church. The issue to be resolved is its shape and the way it is implemented.Utworzone w maju 1948 r. Państwo Izrael określiło nowe ramy prawne dla Kościołów znajdujących się na jego terytorium. W Deklaracji Niepodległości zagwarantowano wolność wyznania i kultu dla wszystkich obywateli. Jednakże od samego początku pojawił się problem w odniesieniu do Żydów, którzy przeszli na chrześcijaństwo, a których należało objąć opieką duszpasterską, posługując się w tym celu także w liturgii językiem hebrajskim. Wśród pionierów znaleźli się ojcowie: Jean-Roger Héné AA, Joseph Stiassny NCD i Bruno Hussar OP. Pewna niechęć ze strony duchowieństwa arabskiego i europejskiego została przezwyciężona poparciem ze strony zarówno miejscowej hierarchii, jak i watykańskiej. 11 lutego 1955 r. Dzieło Świętego Jakuba zostało zatwierdzone ad experimentum ad annum, a po roku próby 11 lutego 1956 r. Patriarcha zatwierdził jego statuty. Pionierzy Dzieła widzieli w tym wydarzeniu powrót do początku, kiedy to pierwszą kościelną wspólnotą była jerozolimska gmina judeochrześcijańska. Ta próba odtworzenia Kościoła początków miałaby przywrócić element hebrajski utracony w historycznym rozwoju Kościoła. Zagadnieniem do rozstrzygnięcia pozostaje jego kształt i sposób realizacji

CubeSatTOF: Planetary Atmospheres Analyzed with a 1U High-Performance Time-Of-Flight Mass Spectrometer

This paper presents design and performance of a miniature time-of-flight mass spectrometer of 1U size for a CubeSat platform for quantitative chemical composition analysis of thin atmospheres. The atmospheres of solar system bodies harbor key information to answer questions about its origin and evolution, night-side transport, satellite drag including seasonal variation of it, chemical sputtering of satellites, and even the feasibility of earthquake forecast system has been suggested. Highly sensitive chemical analyses with our mass spectrometer will allow to obtain insight into atmospheric processes. We designed a compact multipurpose instrument. Its applicationis discussed for two mission concepts, namely orbiting Earth in a terrestrial swarm configuration or descending through the atmosphere of a planetary object during a flyby. Our measurements demonstrate that the instrument has mass range of about m/z 1 – 300 and a mass resolution so that the heavy noble gases such as krypton and xenon can be quantified in situ. Thanks to its ion optical performance, the CubeSatTOF instrument serves as a baseline technology for future analysis of both the terrestrial and extraterrestrial exospheres

FEATURES OF WEEDINESS OF THE FIELD BY ROOT RESIDUES OF CORN

The presence of a large amount of root residues after harvesting corn creates problems for the processing of the field. On the basis of field and laboratory studies, the character of weediness and the main physical and morphological characteristics of rhizomes were revealed. Analysis of the variation curves of the dimensional characteristics of root residues and the mass graphical dependences of rhizomes made it possible to develop a general approach to freeing fields from plant residues of corn

Life Detection Beyond Earth: Laser-Based Mass Spectrometry for Organics Detection on Solar System Objects

The detection and identification of the building blocks of life, from amino acids to more complex molecules such as certain lipids, is a crucial but highly challenging task for current and future space exploration missions in our Solar System. To date, Gas Chromatography Mass Spectrometry has been the main technology applied. Although it has shown excellent performance in laboratory research, it has not yet been able to provide a conclusive answer regarding the presence or absence of a signature of life, extinct or extant, in space exploration. In this contribution we present the current measurement capabilities of our space prototype laser-based mass spectrometer for organics detection. The developed mass spectrometer currently allows the detection and identification of small organic molecules, such as amino acids and nucleobases, at sample concentrations at the level of femtomole mm-2, using the same measurement protocol. The latter is highly relevant to space exploration, since with the instrumentation in use so far only one class of organics can be measured with one instrument configuration