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50 lat działalności Polskiego Towarzystwa Badań Radiacyjnych im. M. Skłodowskiej-Curie: 1967-2017

Sommer S.

Postępy Techniki Jądrowej

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2017

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z. 3

12--17

PL

W 2017 r. Polskie Towarzystwo Badań Radiacyjnych (PTBR) obchodzi 50-lecie swojego powstania. Utworzenie Towarzystwa miało na celu: rozwój kontaktów naukowych między poszczególnymi instytutami, laboratoriami, grupami badawczymi i stowarzyszeniami w kraju i za granicą, zajmującymi się tematami związanymi z promieniowaniem, organizację spotkań naukowców z różnych dziedzin, wymianę doświadczeń, organizację kursów doszkalających, działalność wydawniczą, a także popularyzację nauki. Te funkcje wypełniane są z powodzeniem do dnia dzisiejszego. Zebranie założycielskie PTBR odbyło się 29 czerwca 1967 r. w Pałacu Kultury i Nauki w Warszawie i tę datę uznajemy za dzień narodzin Towarzystwa. Od 1969 r. PTBR organizuje Zjazdy Naukowe - do tej pory odbyło się ich 17, a od 1970 r. - Szkoły Jesienne (odbyło się ich 24). W trakcie Zjazdów wręczane są nagrody naukowe oraz (od 1983 r.) prestiżowe medale im. Marii Skłodowskiej-Curie. W artykule omówiono narodziny Towarzystwa i główne formy jego działalności oraz osiągnięcia.

EN

In 2017, Polish Radiation Research Society (PRRS) celebrates the 50th anniversary of its founding. The formation of the Society was aimed at: the development of scientific contacts between various institutes, laboratories, research groups and associations in the country and abroad, dealing with radiation related topics in the country and abroad, organizing meetings of scientists of various fields, exchange of experiences, organization of refresher courses, publishing activities, and popularization of science. These functions are successfully fulfilled to this day. The founding meeting of PRRS took place on June 29, 1967, at the Palace of Culture and Science in Warsaw, and we recognize this date as the day of the birth of the Society. Since 1969 the PRRS has organized Scientific Meetings - which so far have been held 17 times, and since 1970 - the Autumn Schools (held 24 times). During the meetings Scientific Awards of PRRS and (since 1983) the prestigious medals of Maria Skłodowska-Curie are awarded. The article describes the birth of the Society, the main forms of its activity, and achievements.

2

Ambient fields generated by a laser spark

Rohlena K., Mašek M.

Nukleonika

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2016

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Vol. 61, No. 2

119--124

EN

The electric and magnetic fields surrounding a laser spark formed after an optical breakdown due to a focused nanosecond laser beam in a gaseous environment are examined in order to assess their possible influence on the processes going on in the gas medium, mainly chemical reactions triggered by the spark plasma radiation. The magnetic field is generated by the standard mechanism of crossed electron density and temperature gradients, the electric field is supposed to be produced by the plasma polarization due to its radial expansion across the self-generated magnetic field. A simple model of spark plasma formation near the tip of the focal cone is assumed, with a delayed breakdown, which allows the focused laser light to sweep the whole volume of the forming spark right down to the focal caustic and thus to form a centimeter long plasma cone. In this conical geometry, the value of plasma electric dipole moment is evaluated as a measurable quantity as well as approximate values of the electric and magnetic field near the focal caustic, where they both tend to grow in magnitude.

3

Od Marii Skłodowskiej-Curie do współczesnych technologii radiacyjnych

Głuszewski W., Zagórski Z. P.

Kwartalnik Historii Nauki i Techniki

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2012

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R. 57, nr 1

71--88

EN

The article was written on the occasion of the 100. anniversary of the Nobel Prize in Chemistry awarded to Maria Skłodowska-Curie. The United Nations General Assembly honoured this event by announcing the year 2011 the International Year of Chemistry. Maria Skłodowska-Curie was i.a. the initiator of radiation chemistry, a branch of science analyzing the chemical effects that matter shows when exposed to ionizing radiation. The development of this branch resulted in radiation technologies’ applications in many fields of industry, medicine, agriculture, protection of the environment, space research and science. Our point of departure was the article Sur l’étude des courbes de probabilité relatives à l’action des rayons X sur les bacilles that Maria Skłodowska-Curie published in 1929 in the Bulletin of the Académie des sciences. In this study, she presented - for the first time ever - the curves of the so called radiation inactivation, i.e. the relationship between the bacteria life expectancy and the dose of radiation absorbed by it. From the today’s point of view, it can be stated that the researcher laid the foundations of the methods of radiation sterilization and material processing by means of radiation. In this context, we recall the history of the first accelerator installation devised and built in 1968 at the Institute of Nuclear Chemistry and Technology in Warsaw. Basing on experiences with the linear electron accelerator, the LAE 13/9 was completed in 1992 as the so far only Polish industrial installation for radiation sterilization of medical products and transplants as well as for food irradiation.

4

Radiacyjna modyfikacja elastomerów

Zagórski Z. P., Rajkiewicz M., Głuszewski W.

Przemysł Chemiczny

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2011

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T. 90, nr 6

1191-1194

5

Historic landmarks in radiation chemistry since early observations by Marie Skłodowska-Curie and Pierre Curie

Belloni J.

Nukleonika

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2011

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Vol. 56, No. 3

203-211

EN

The origin of the radiation chemistry history is contemporary with the X-rays and uranic rays discoveries. The complexity of the phenomena induced by the radiation effects, which involve electrons, ions and free radicals and a specific spatial distribution of the energy deposit along the tracks, was progressively understood, particularly when pulse radiolysis and time-resolved detection permitted to observe the short-lived transient species and to explain the chemical or biochemical mechanims. This short review summarizes the most important landmarks of the concepts and their applications.

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Zastosowanie chemii radiacyjnej w modyfikacji materiałów i ochronie środowiska

Chmielewski A.G.

Wiadomości Chemiczne

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2007

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[Z] 61, 7-8

515-546

EN

Radiation chemistry is a part of the physical chemistry similary like photo-chemistry, plasma-chemistry, ultrasonic-chemistry etc. Ionizing radiation produces abundant secondary electrons. Following these primary events, the ions, secondary electrons and excited molecules undergo further transformations, exchanging charges and energy and reacting with surrounding molecules, thereby producing free radicals and other reactive species which finally evolve into new stable products. Three main sources of radiation are applied for radiation processing]. These are electron accelerators], gamma sources and X-ray unit based on e-/X conversion process. Radiation processing was used early on for polymer modification. The intermediates formed during material irradiation can follow several reaction paths that result in disproportion, hydrogen abstraction, arrangements and/or the formation of new bonds. Nowadays, the modification of polymers covers radiation cross-linking, radiation-induced polymerization (graft polymerization and curing) and the degradation of polymers. Some polymers predominantly undergo crosslinking other degradation. However new techniques allow crosslinking of polymers which were considered to be degradable only, like PTFE and cellulose derivatives. Regarding natural polymers the biggest application concerns rubber pre-crosslinking in tire industry. The processing of natural polymers is also being developed to elaborate new biodegradable materials. The radiation crosslinked wires and cables show excellent heat resistance (long-term thermal stability and short-term thermal stability) as well as abrasion resistance. Other big application is crosslinking of XLPE type pipes which are widely used for hot water and floor heating. Polybutelene terephtalate (PBT), which is a plastic for electronic industry, can be crosslinked by radiation and lead free soldering materials can be applied in such a case. This method of crosslinking is also applied to manufacture thermoshrinkable tubes and types possessing "memory effect". Through radiation, grafting metal adsorbents and ion exchange membranes can be developed. Radiation is early applied tool in the area of nanomaterials engineering; arrangement of atoms and ions has been performed using ion or electron beams for many years. New trends concern surface curing and development of ion track membranes and controlled release drug-delivery systems. Finally, radiation processing concerns gem stones colorization, development of high temperature resistant fibers (SiC) and semiconductor modification. Over the past few years, radiation processing technologies aimed at ensuring the safety of gaseous and liquid effluents discharged to the environment have been developed. It has been demonstrated that radiation processing based technologies for flue gas treatment (SOX and NOX removal), wastewater purification, and sludge hygienization can be effectively deployed to mitigate environmental degradation. Electron beam technology is among the most promising advanced technologies of new generation. This is a dry-scrubbing process of simultaneous SO2 and NOx removal, where no waste except the fertilizer by-product are generated.The other possibility is application of the process for VOC removal. Tests at the pilot plant constructed at a coal-fired power station were performed with the purpose of estimating the influence of electron beam on VOCs present in flue gas, during SO2 and NOx removal. The removal efficiencies have been ranged from 40% up to 98%. The chlorocarbons including dioxins may be removed with high efficiency as well. During the radiolysis of water reactive radicals of strong oxidizing or reducing properties are formed that can transform the pollutants in the liquids wastes. A large number of substances such as hard surfactants, lignin, pesticides cannot be degraded by conventional biochemical methods and thus escape from decomposition in biological treatment. Research and industrial treatments testify significant improvement of pollutant biodegradability after radiation-oxidation in aerated wastewater.

7

Praktyczne aspekty chemii radiacyjnej

Chmielewski A. G.

LAB Laboratoria, Aparatura, Badania

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2007

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R. 12, nr 1

10-18

8

Radiation chemistry in exploration of Mars

Zagórski Z.

Nukleonika

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2005

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Vol. 50,suppl.2

59-63

EN

Problems of exploration of Mars are seldom connected with radiation research. Improvements in such approach, more and more visible, are reported in this paper, written by the present author working on prebiotic chemistry and origins of life on Earth. Objects on Mars subjected to radiation are very different from those on Earth. Density of the Martian atmosphere is by two orders smaller than over Earth and does not protect the surface of Mars from ionizing radiations, contrary to the case of Earth, shielded by the equivalent of ca. 3 meters of concrete. High energy protons from the Sun are diverted magnetically around Earth, and Mars is deprived of that protection. The radiolysis of martian "air" (95.3% of carbon dioxide) starts with the formation of CO2 +, whereas the primary product over Earth is N2 + ionradical. The lack of water vapor over Mars prevents the formation of many secondary products. The important feature of Martian regolith is the possibility of the presence of hydrated minerals, which could have been formed milliards years ago, when (probably) water was present on Mars. The interface of the atmosphere and the regolith can be the site of many chemical reactions, induced also by intensive UV, which includes part of the vacuum UV. Minerals like sodalite, discovered on Mars can contribute as reagents in many reactions. Conclusions are dedicated to questions of the live organisms connected with exploration of Mars; from microorganisms, comparatively resistant to ionizing radiation, to human beings, considered not to be fit to manned flight, survival on Mars and return to Earth. Pharmaceuticals proposed as radiobiological protection cannot improve the situation. Exploration over the distance of millions of kilometers performed successfully without presence of man, withstands more easily the presence of ionizing radiation.

9

Chemia radiacyjna a elastomery

Zagórski Z.P., Rajkiewicz M.

Elastomery

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2003

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T. 7, nr 4

9-17

PL

W artykule omówiono elementy chemii radiacyjnej wspólne wszelkim polimerom, a więc dotyczące i elastomerów, na tle chemii radiacyjnej ośrodków stałych. Omówiono dotychczasowe publikacje na temat chemii radiacyjnej wybranych elastomerów, ze szczególnym uwzględnieniem wcześniejszego dorobku w tej dziedzinie Zakładu Chemii Radiacyjnej Instytutu Badań Jądrowych w Warszawie. Zwrócono uwagę na elementy chemii i fizykochemii elastomerów w przebiegu reakcji inicjowanych promieniowaniem jonizującym. Przedstawiono prognozy, co do kierunku dalszego rozwoju obróbki radiacyjnej elastomerów wiązką elektronów dużej mocy. Przegląd dotyczy założeń grantu KBN zrealizowanego w latach 2001-2004.

EN

Elements of radiation chemistry common for elastomers and all other polymers, on the background of radiation chemistry of solid phase are presented in this article. The discussion of publications dealing with radiation chemistry of selected elastomers, with consideration of early achievments of the Department of Radiation Chemistry in the Institute of Nuclear Research. Elements of chemistry and physical chemistry of elastomers, which influence the course of reactions initiated by ionizing radiation, are discussed. Assumptions are expressed, concerning the future developments of applications of high power EB radiation processing of elastomers. The present survey is connected with the grant of Polish Committee of Scientific Research, realized in 2001-2004.

10

Chemia radiacyjna i powstanie życia na Ziemi

Zagórski P.

Wiadomości Chemiczne

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2001

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[Z] 55, 11-12

965-985

EN

Radiation chemistry, i.e. the chemical changes initiated by the absorption of ionizing radiations, have to be considered in three chapters of discussions on the mechanisms of origins of life on Earth. i: Much higher level of ionizing radiations on Earth than now, has given rise to intensive radiation chemistry. It played an important rôle in the formation of prebiotic organic compounds, by the abstraction of electrons from simple compounds, and leaving positive species, also very reactive. In the subsequent processes, free radicals were formed, which created new combinations and even the formation of compounds of increased molecular weight; chemical chain reactions were also initiated, all entirely at ambient temperature. However, all these reactions were not chiral in their nature, and, as far as the experiments indicate, were not able to replicate or to be amplified. ii: In the stadium of the creation of life in the "soup" formed by different variations of high energy chemistry, radiation chemistry does not seem to be important. In spite of initial great hopes, created by physicists, the reactions initiated by ionizing radiations were of low enantioselectivity i.e. were not able to enrich one of the enantiomere, or amplify effects which could appear initially. In particular, the hopes laid in the role of the violation of parity, e.g. in the case of b-radiation, as the force promoting chirality, were not fulfilled [c.f. 16]. iii: In the lack of reasonable mechanisms for the origins of life on Earth, many researchers are looking for origins of life from the outside of the Earth. However, that approach does not solve the problem of chiral synthesis and creates additional problems of the transportation of living matter. In that respect the radiation chemistry and its biological consequence - radiobiology is univocal: ionizing radiations, filling the universe, of action extended for years, cause total inactivation of every life, even the primitive one, like in the shape of viruses. The main destructive chemistry is dehydrogenation of live organisms and dry spores, which occurs even at low temperatures, close to absolute zero. Much lower doses, of single Gy (grays) to the whole body are sufficient to destroy the human life, already during the travel to and back from Mars. The shielding atmosphere of gases around the Earth is equivalent to 10 meters thick layer of concrete. A construction and operation of a ship, which could secure the survival of the crew, by making conditions of radiation background as safe as on Earth, is impossible. For the same reasons, radiation chemistry excludes the arrival of "aliens", E.T. etc on Earth. Radiation chemistry does not exclude the possibility of Life in any part of the Universe, sufficiently shielded, but shows impossiblity of the transportation of live precursors of our life to the Earth. The Life on Earth originated here and any models of its formation, if true, have to be a subject of reconstruction in the laboratory.

11

Radiation chemistry of solid thiosulfate: optical absorption spectra

Zagórski Z., Rafalski A.

Nukleonika

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2000

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Vol. 45, nr 1

109-113

EN

Solid sodium thiosulfate, anhydrous and hydrated (5 H2O), was irradiated with 10 MeV electrons in a pulsed, high-dose (30 kGy) rate regime. The resulting optical absorption was measured by diffuse reflection spectophotometry (DRS) (absorption band in anhydrous salt at 360 nm, in hydrated salt at 418 nm). Absorption decays occurred at t1/2 = 80 h (anhydrous) and t1/2 = 9 h (hydrated) at room temperature. The yellowish radical ion formed in irradiated anhydrous thiosulfate was identified as [źS2O3]-, and not [źS2O3]3-, as proposed in previous nonoptical (EPR) investigations. The absorption spectrum of [źS2O3]- in a solid matrix was similar to the transient spectrum ascribed to the same radical, obtained by pulse radiolysis in aqueous solution, and had a lifetime many orders of magnitude shorter. A similar radical anion, but in the complex with adjacent water molecules from the hydration moiety, was observed in hydrated thiosulfate (Na2S2O3ź5 H2O).