Thermal Alteration of Labile Elements in Carbonaceous Chondrites

Carbonaceous chondrite meteorites are some of the oldest Solar System planetary materials available for study. The CI group has bulk abundances of elements similar to those of the solar photosphere. Of particular interest in carbonaceous chondrite compositions are labile elements, which vaporize and mobilize efficiently during post-accretionary parent-body heating events. Thus, they can record low-temperature alteration events throughout asteroid evolution. However, the precise nature of labile-element mobilization in planetary materials is unknown. Here we characterize the thermally induced movements of the labile elements S, As, Se, Te, Cd, Sb, and Hg in carbonaceous chondrites by conducting experimental simulations of volatile-element mobilization during thermal metamorphism. This process results in appreciable loss of some elements at temperatures as low as 500 K. This work builds on previous laboratory heating experiments on primitive meteorites and shows the sensitivity of chondrite compositions to excursions in temperature. Elements such as S and Hg have the most active response to temperature across different meteorite groups. Labile element mobilization in primitive meteorites is essential for quantifying elemental fractionation that occurred on asteroids early in Solar System history. This work is relevant to maintaining a pristine sample from asteroid (101955) Bennu from the OSIRIS-REx mission and constraining the past orbital history of Bennu. Additionally, we discuss thermal effects on surface processes of near-Earth asteroids, including the thermal history of "rock comets" such as (3200) Phaethon. This work is also critical for constraining the concentrations of contaminants in vaporized water extracted from asteroid regolith as part of future in situ resource utilization for sustained robotic and human space exploration.Comment: 12 pages of text, 3 tables, 7 figures, accepted by Icaru

EFECT OF SMOKING ON THE ACCUMULATION OF POLYCYCLIC AROMATIC HIDROCARBONS, IN M. LONGISIMUS DORSI FROM PIGS AND POSSIBILITIES FOR REDUCING THEIR CONTENT

This study deals with the effect of smoking process and the accumulation of toxic polycyclic aromatic hydrocarbons in Musculus Longissimus dorsi from pigs and studies the possibilities to reduce their content. The studies were conducted on two samples boiled-smoked fillet – one salted with brine and added proteincoating, whereas the second one salted with brine and added ascorbic acid.Qualitative identification and quantification of polycyclic aromatic hydrocarbons is done by gas hromotograph Hewlett Packard 5890 with LG 85 B spectrophotometric detector. It was found that the use of proteincoatings, significantly reduces the amount of polycyclic aromatic hydrocarbons in the smoking of Musculus Longissimus dorsi from pigs. The addition of ascorbic acid in conjunction with protein salting coatings technology represents a significant option for reducing the content of the benzo(a)pyrene , which contributes to the safety in the final products. In studies of the samples of proteins and ascorbic acid, the inner layers i.e the muscle tissue was found to contain significantly less amount of benzo(a)pyrene (1,75 ± 0,06 μ/kg) compared with the values found in the surface layers (2,31 ± 0,02 μg/kg)

Plasma Enhanced Chemical Vapor Deposited Materials and Organic Semiconductors in Photovoltaic Devices

Introduction. PECVD enables fabrication of wide range of advanced materials with various structure such as amorphous, polymorphous, nano-crystalline, nanostructured, microcrystalline etc. and with various electronic properties. The latter can be also changed by different dopingl. PECVD silicon materials are commercially employed in multi-layered PV structures (including ones on flexible substrates). Combining these materials with crystalline silicon active substrate resulted in significant improvement of PCE in hetero junction technology PV structures. Existence of new organic semiconductors (OS) together with understanding of physical properties resulted in fast development of OC PV devicesAim. To consider both PECVD and OS materials and to present description of fabrication, structure and electronic properties for device application.Materials and methods. Devices based on non-crystalline materials, devices based on OS, hybrid devices. PECVD and Spin coating technique was used to deposit materials with tunable properties enabling device engineering possibilities.Results. PECVD and OS materials were analyzed. These materials have different levels of characterization (data volume, interpretation of the results etc.) and of understanding of physics determining device performance. Some examples of these materials in PV including structures with crystalline silicon were considered.Conclusion. Important advantage of both PECVD and OS materials is that fabrication methods are compatible and allow fabrication of great variety of hybrid device structures on crystalline semiconductors. Advantages of such devices are difficult to predict because of lack of data in scientific literature. However a new area in material science and related devices for further exploring and exploiting has appeared.Introduction. PECVD enables fabrication of wide range of advanced materials with various structure such as amorphous, polymorphous, nano-crystalline, nanostructured, microcrystalline etc. and with various electronic properties. The latter can be also changed by different dopingl. PECVD silicon materials are commercially employed in multi-layered PV structures (including ones on flexible substrates). Combining these materials with crystalline silicon active substrate resulted in significant improvement of PCE in hetero junction technology PV structures. Existence of new organic semiconductors (OS) together with understanding of physical properties resulted in fast development of OC PV devices.Aim. To consider both PECVD and OS materials and to present description of fabrication, structure and electronic properties for device application.Materials and methods. Devices based on non-crystalline materials, devices based on OS, hybrid devices. PECVD and Spin coating technique was used to deposit materials with tunable properties enabling device engineering possibilities.Results. PECVD and OS materials were analyzed. These materials have different levels of characterization (data volume, interpretation of the results etc.) and of understanding of physics determining device performance. Some examples of these materials in PV including structures with crystalline silicon were considered.Conclusion. Important advantage of both PECVD and OS materials is that fabrication methods are compatible and allow fabrication of great variety of hybrid device structures on crystalline semiconductors. Advantages of such devices are difficult to predict because of lack of data in scientific literature. However a new area in material science and related devices for further exploring and exploiting has appeared

Ocenjivanje performansi zaposlenih kao društvena odgovornost preduzeća

Evaluating the performance of employees in the meat industry is the process by which evaluate the contribution of employees and their responsibility in achieving organizational objectives in some defined time period. The responsibility is a moral action of people and companies. Performance or effects, may be any measurable results achieved, any behavior or personal characteristics necessary to perform certain activities. Social responsibility includes economic, legal, ethical and philanthropic responsibility. Corporate social responsibility is seen as a promotion of some social goods above the interests of the company, than what the law requires. It is possible to determine the level of social responsibility to maximize profit while satisfying the demands of many consumers, who consume meat and meat products. Activities in promoting social responsibility in this regard should be viewed from the perspective of benefits and costs.Ocenjivanje performansi zaposlenih u mesnoj industriji je proces u kojem se ocenjuje doprinos zaposlenih i njihova odgovornost u ostvarenju organizacionih ciljeva u nekom definisanom vremenskom periodu. Odgovornost je moralna akcija ljudi i preduzeća. Performansa ili učinak može biti bilo koji merljiv rezultat koji je ostvaren, bilo ponašanje ili lićne karakteristike neophodne za obavljanje odredene aktivnosti. Društvena odgovornost uključuje ekonomsku, pravnu, etičku i filantropsku odgovornost. Društvena odgovornost preduzeća se posmatra kao unapređenje nekih društvenih dobara iznad interesa preduzeća od onoga što traži zakon. Moguće je ustanoviti nivo društvene odgovornosti koji maksimira dobit uz istovremeno zadovoljavanje zahteva brojnih potrošača Koji konzumiraju meso i mesne prоizvode. Aktivnosti na unapređenju društvene odgovornosti u tom smislu treba posmatrati sa stanovišta koristi i troškova

Učešće sadržaja proteina dobijenih od svinjskih kožica u barenim kobasicama proizvedenim od svinjskog mesa

The aim of our study was to determine the participation of protein content received from pork skins in cooked pork sausage and their economic cost-effectiveness. Taken were frozen pork skins from Macedonian origin. Tested were chemical and microbiological composition of pork skins and emulsion before and after cuterring. First, the pork skins are thawed and 24 hours immersed in a solution of the acid, then washed with water and well drained. Emulsion of skins are prepared in that manner: 20 kg skins + 20 kg water (ice) + 200 g soy proteins. Approximately, 20% of the emulsion of skins were been installed in seven different batches of cooked pork sausage, in which after the heat treatment is determined by the chemical and microbiological composition. With chemical analysis we found, the amount of protein in the pork skin several lower of emulsions of the skin, while the quantity of protein in cooked pork sausage in the range of 12.20 to 14.82 %. With microbiological analysis we not found bacteria of the genus Clostridium, Staphylocoscus, Proteus, Escherichia in the skin and emulsion of skins and cooked pork sausages. The total number of bacteria (Bacillus) is increased after cuttering in the emulsion of skins (2.90 log CFU/g) in comparisons with pork skins (2.44 log CFU/g), while the finished product after thermal treatment of the total number of bacteria in the border from 1.30 to 1.69 log CFU/g.Cilj našeg istrażivanja bio je da se utvrdi učešče sadrżaja proteina dobijenih od svinjskih kożica u barenim kobasicama proizvedenim od svinjskog mesa i ekonomska isplatlivost njihove primene. Uzete su zamrznute svinjske kożice makedonskog porekla i ispitan je hemijski i mikrobiološki sastav svinjskih kożica i emulzije od kożica, pre i nakon kuterovanja. Prvo su svinjske kożice odmrznute i 24 časa potopljene u rastvor kiselina, potom isprane vodom i isceđene. Emulzija od kożica je pripremljena u odnosu: 20 kg svinske kožice + 20 kg vode (leda) + 200 g proteina od soje. Pribliżno, 20% od emulzija kożice je bilo ugraðeno u sedam različitih šarżi barene svinjske kobasice, kojoj je nakon termičke obrade određivan hemijski i mikrobiološki sastav. Hemijskom analizom utvrdili smo da je sadržaj proteina u svinskoj kożici nekoliko puta niżi od sadržaja proteina u emulziji kożice, dok je sadržaj proteina u barenoj svinjskoj kobasici u opsegu od 12,20 do 14,82%. Mikrobiološkom analizom nismo utvrdili bakterije iz roda Clostridium, Staphylocoñcus, Proteus, Escherichia u kożicama, emulziji od kożica i u barenoj svinjskoj kobasici. Ukupan broj bakterija (Bacillus) je uvećan posle kuterovanja u emulziji od kożica (2,90 log CFU/g) u poređenju sa svinjskim kożicama (2,44 log CFU/g) dok je u gotovom proizvodu posle termičke obrade ukupan broj bakterija u granici od 1,30 do 1,69 log CFU/g

In search for fingerprints of an extraterrestrial event: Trace element characteristics of sediments from the lake Medvedevskoye (Karelian Isthmus, Russia)

Concentration and distribution of trace elements across the sequence of the Late Pleistocene sediments from the lake Medvedevskoye suggest the addition of materials other than those from a common source for the lake sediments of the region. The sediments of the lake Medvedevskoye carry some geochemical fingerprints which could be related the ET event that occurred at ca. 12.9 ka. Because such fingerprints are extremely subtle, the NW Russia can be considered to be the most remote eastern region of the extent of the Late Pleistocene airborne ET material. The sediments of the lake Medvedevskoye can also contain volcanic material from the eruption of the Laacher See (Germany) volcano and probably from other Late Pleistocene volcanoes of Western Europe and/or Iceland. © 2014 Pleiades Publishing, Ltd

Paleolimnological studies in Russian northern Eurasia: A review

© 2017, Pleiades Publishing, Ltd. This article presents a review of the current data on the level of paleolimnological knowledge about lakes in the Russian part of the northern Eurasia. The results of investigation of the northwestern European part of Russia as the best paleolimnologically studied sector of the Russian north is presented in detail. The conditions of lacustrine sedimentation at the boundary between the Late Pleistocene and Holocene and the role of different external factors in formation of their chemical composition, including active volcanic activity and possible large meteorite impacts, are also discussed. The results of major paleoclimatic and paleoecological reconstructions in northern Siberia are presented. Particular attention is given to the databases of abiotic and biotic parameters of lake ecosystems as an important basis for quantitative reconstructions of climatic and ecological changes in the Late Pleistocene and Holocene. Keywords: paleolimnology, lakes, bottom sediments, northern

OSIRIS-REx Contamination Control Strategy and Implementation

OSIRIS-REx will return pristine samples of carbonaceous asteroid Bennu. This manuscript describes how pristine was defined based on expectations of Bennu and on a realistic understanding of what is achievable with a constrained schedule and budget, and how that definition flowed to requirements and implementation. To return a pristine sample, the OSIRIS-REx spacecraft sampling hardware was maintained at Level 100 A/2 and less than 180 nanograms per square centimeter of amino acids and hydrazine on the sampler head through precision cleaning, control of materials, and vigilance. Contamination is further characterized via witness material exposed to the spacecraft assembly and testing environment as well as in space. This characterization provided knowledge of the expected background and will be used in conjunction with archived spacecraft components for comparison with the samples when they are delivered to Earth for analysis. Most of all, the cleanliness of the OSIRIS-REx spacecraft was achieved through communication between scientists, engineers, managers, and technicians