Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "nuclear reactions" wg kryterium: Temat


Wyświetlanie 1-10 z 10
Tytuł:
On the influence of gas puff loads on plasma focus dynamics
Autorzy:
Schmidt, H.
Powiązania:
https://bibliotekanauki.pl/articles/971523.pdf
Data publikacji:
2001
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
computer modelling
gas puffing
nuclear fusion
nuclear reactions
plasma focus
Z-pinch
Opis:
The plasma focus is a source of pulsed radiation, which is of interest in various fields of physics and technology. Applications include soft X-ray microscopy, soft X-ray and electron beam lithography. The plasma focus is also a highly efficient source of fast neutrons. If one applies gas puffing instead of static filling, decoupling of plasma conditions in the breakdown and compression phases can be achieved. Results of experiments with a fast valve and accompanying 2D modelling of the dynamic gas target are presented. Among other advantages of gas puffing, neutron yield could be increased up to a factor of three in appropriate experiments. The concept of gas puffing has been extensively investigated in many Z-pinch experiments including multiple gas puffs. It seems desirable to increase the efforts to understand and optimise the gas puffing option for small and large plasma focus devices.
Źródło:
Nukleonika; 2001, 46, 1; 15-19
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The “Renaissance” in Nuclear Physics: Low-Energy Nuclear Reactions and Transmutations
Autorzy:
Di Sia, Paolo
Powiązania:
https://bibliotekanauki.pl/articles/1158761.pdf
Data publikacji:
2018
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Biot-Savart law
Classical physics
Low-energy nuclear reactions
Magnetic attraction
Nuclear binding energies
Nuclear physics
Transmutations
Opis:
Nuclear structure theory has recently undergone an unexpected “renaissance” that can be attributed to two factors: (a) Since 1989, experimental findings have indicated isotopic anomalies in “chemical systems” at energies well below the expected ~10 MeV nuclear level. (b) Since 2007, remarkable ab initio super-computer calculations of nuclear properties have been made under the assumption that nucleons have well-defined intranuclear positions (x ≤ 2 fm). Assuming a magnetic structure of nucleons consistent with classical physics, we have made related lattice calculations of nuclear binding energies and magnetic moments. Our results compare favorably with results from other Copenhagen-style nuclear models.
Źródło:
World Scientific News; 2018, 114; 195-207
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis of heaviest nuclei and heaviest chemical elements
Autorzy:
Sobiczewski, A.
Powiązania:
https://bibliotekanauki.pl/articles/146684.pdf
Data publikacji:
2011
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
heaviest nuclei
heaviest chemical elements
nuclear reactions
alfa-decay energy
alfa-decay half-life
alfa-decay genetic chains
Opis:
Studies of the heaviest nuclei and heaviest chemical elements are shortly described. Methods of synthesis and identification of these nuclei are discussed. Some details of the studies are illustrated on the example of the nucleus 277Cn, the isotope of the element 112 (copernicium) the discovery of which has been recently approved by IUPAC. General results of the research on superheavy nuclei (atomic number Z = 104–118), synthesized within the period from 1969 (discovery of rutherfordium, Z = 104) up to the present are outlined.
Źródło:
Nukleonika; 2011, 56, 3; 212-216
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Production of 166Ho and 153Sm using hot atom reactions in neutron irradiated tris(cyclopentadienyl) compounds
Autorzy:
Nassan, L.
Achkar, B.
Yassine, T.
Powiązania:
https://bibliotekanauki.pl/articles/147591.pdf
Data publikacji:
2011
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
hot atom reactions
holmium-166
miniature nuclear source reactor (MNSR)
Opis:
The behavior of a recoiled 166Ho and 153Sm resulting from the reactions 165Ho(n,gamma)166Ho and 152Sm(n,gamma)153Sm in the organometallic compounds tris(cyclopentadienyl)holmium (C5H5)3Ho(III), and tris(cyclopentadienyl)samarium (C5H5)3Sm(III) were investigated. Several chemical separation methods were developed for each compound to separate the recoil products from the irradiated compound. Retention value of 0.2 �} 0.1% was obtained for (C5H5)3Ho(III) using sublimation. Another value of retention of 0.4 plus or minus 0.1% resulted when column chromatography was used. Paper chromatography (using Whatman Chr. 1 and Whatman Chr. 4) gave different retention values of about 0.11 plus or minus 0.05%, and 0.4 plus or minus 0.1%, respectively. Similar behavior of 153Sm in irradiated (C5H5)3Sm(III) was found when paper chromatography was used for separation. The different retention values given by different methods of separation were discussed. An important improvement of the specific activity was achieved as compared with other published results in this field. The obtained results pointed out that tris(cyclopentadienyl)holmium and samarium could be used to produce high specific activity of 166Ho and 153Sm in the Syrian low flux miniature nuclear source reactor (MNSR), where the averaged achieved enrichment factor for holmium compound was found to be greater than 1.6 x 107.
Źródło:
Nukleonika; 2011, 56, 4; 263-267
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative study of uni-univalent H⁺/Na⁺ and uni-bivalent H⁺/Ca²⁺ ion exchange reactions using nuclear grade resin Indion-223
Autorzy:
Singare, P. U.
Mohammed, A. L. K.
Dixit, N. N.
Powiązania:
https://bibliotekanauki.pl/articles/411747.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
ion exchange reactions
nuclear grade resins
cation exchange resins
enthalpy
equilibrium constant
Indion-223
Opis:
The present paper deals with the ion exchange equilibrium studies of uni-univalent and uni-bivalent ion exchange reactions using nuclear grade anion exchange resin Indion-223 in H⁺ form towards Na⁺ and Ca²⁺ ions in the solution. It was observed that with rise in temperature the equilibrium constants K values for H⁺/Na⁺ uni-univalet ion exchange reaction increases from 0.01389 to 0.01855. Similarly for H⁺/Ca²⁺ uni-bivalet ion exchange reaction the equilibrium constants K values increases from 0.000397 to 0.000639. The increase in equilibrium constant values with rise in temperature indicate endothermic ion exchange reactions having the enthalpy change values of 25.55 and 38.92 kJ/ mol respectively.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 14, 2; 127-135
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on preferential selectivity of nuclear grade resin Indion-223 towards some bivalent ions
Autorzy:
Singare, P. U.
Mohammed, A. L. K.
Dixit, N. N.
Powiązania:
https://bibliotekanauki.pl/articles/412085.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
bivalent exchange reactions
nuclear grade resins
cation exchange
reaction thermodynamics
enthalpy change
ionic selectivity
equilibrium constant
Indion-223
Opis:
In the present paper attempts are made to understand the selectivity of nuclear grade cation exchange resin Indion-223 in H+ form towards Ca2+ and Mg2+ bivalent ions in the solution based on thermodynamic concept. It was observed that with rise in temperature the equilibrium constant K values for H+/Ca2+ uni-bivalet ion exchange reactions increases from 0.000397 to 0.000639. Similarly for H+/Mg2+ uni-bivalet ion exchange reactions the equilibrium constant K values increases from 0.000177 to 0.000333. The increase in equilibrium constant values with rise in temperature indicate endothermic ion exchange reactions having the enthalpy change values of 38.92 and 51.46 kJ/ mol respectively. The difference in K values and enthalpy values were used to predict the selectivity behaviour of the resin towards the Ca2+ and Mg2+ bivalent ions in the solution. The thermodynamic concept of the present study can be applied to understand the selectivity behaviour of different nuclear as well as non-nuclear grade resins towards wide range of ionic species present in the exchanging liquid medium.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 15; 11-21
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermodynamic study to evaluate the selectivity behaviour of nuclear grade resin Indion-223 towards some univalent ions
Autorzy:
Singare, P. U.
Mohammed, A. L. K.
Dixit, N. N.
Powiązania:
https://bibliotekanauki.pl/articles/412486.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
uni-univalent ion exchange reactions
ionic selectivity
nuclear grade resins
cation exchangers
enthalpy change
equilibrium constant
Indion-223
Opis:
The present paper deals with the application of thermodynamic concept in understanding the preferential selectivity of nuclear grade anion exchange resin Indion-223 in H+ form towards Na+ and K+ ions in the solution. In the study it was observed that the equilibrium constants K values for H+/Na+ and H+/K+ uni-univalet ion exchange reactions increases from 0.01389 to 0.01855 and from 0.01710 to 0.02374 respectively as the temperature increases from 35.0 °C to 45.0 °C. The increase in K values with rise in temperature suggests endothermic ion exchange reactions having the enthalpy change values of 25.55 and 22.72 kJ/ mol respectively. Based on difference in K values and enthalpy values for the two uni-univalent ion exchange reactions, the preferential selectivity of the resin for the univalent ions in the solution was predicted. From the results of present study, it appears that the experimental technique used here can be applied further to understand the ionic selectivity of different industrial grade ion exchange resins. It is expected that such studies will provide valuable information in order to decide about the selection of those resins for efficient separation of various ionic species present in the industrial waste water effluents.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 15; 22-29
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on Halide Ions Selectivity of Nuclear Grade Anion Exchange Resin Auchlite ARA-9366
Autorzy:
Singare, P. U.
Patange, A. N.
Powiązania:
https://bibliotekanauki.pl/articles/412305.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
selectivity
ion exchange reactions
halide ions
nuclear grade resins
anion exchange resins
enthalpy
equilibrium constant
Auchlite ARA-9366
Opis:
The selectivity behaviour of nuclear grade anion exchange resin Auchlite ARA-9366 in chloride form towards iodide and bromide ions in the solution was studied. The trend in selectivity of the resin was predicted on the basis of thermodynamics of Clˉ/Iˉ and Clˉ/Brˉ uni-univalent ion exchange reactions. It was observed that the equilibrium constants K values for Clˉ/Iˉ ion exchange reaction were higher than that calculated for Clˉ/Brˉ exchange under identical experimental conditions. Also the enthalpy values for the two uni-univalent ion exchange reactions were calculated as -47.87 and -36.14 kJ/mol respectively. The high K and low enthalpy values obtained for Clˉ/Iˉ ion exchange reaction as compared to that obtained during Clˉ/Brˉ exchange supports higher selectivity of the resin towards iodide ions as compared to that towards bromide ions, when both the ions are present in the same solution.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 11, 1; 67-73
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Nondestructive Radio Tracer Technique in Performance Evaluation of Anion Exchange Resins Duolite ARA-9366 and Duolite A-171
Autorzy:
Singare, P. U.
Powiązania:
https://bibliotekanauki.pl/articles/412526.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
non-destructive tracer technique
radio analytical technique
radioactive tracer isotopes
131I
82Br
reaction kinetics
ion-isotopic exchange reactions
nuclear grade resin
Duolite ARA-9366
Duolite A-171
Opis:
Radio analytical technique as a non-destructive technique was used in the present investigation to trace the kinetics of ion-isotopic exchange reaction taking place in Duolite ARA-9366 (nuclear grade) and Duolite A-171 (non-nuclear grade) anion exchange resins. The kinetics data suggest that during iodide ion-isotopic exchange reactions under identical experimental conditions of 40.00C, 1.000 g of ion exchange resins and 0.003 M labeled iodide ion solution, the values of specific reaction rate (min-1), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log Kd were 0.176, 0.383, 0.067 and 7.8 respectively for Duolite ARA-9366 resin, which was higher than 0.142, 0.353, 0.050 and 7.0 respectively as that obtained for Duolite A-171 resins. Also it is observed that at a constant temperature of 40.0 °C, as the concentration of labeled iodide ion solution increases 0.001 M to 0.004 M, the percentage of iodide ions exchanged increases from 49.20 % to 51.80 % for Duolite ARA-9366 resins; and from 45.20 % to 47.80 % for Duolite A-171 resins. The similar trend was observed for the two resins during bromide ion-isotopic exchange reactions. The overall results indicate superior performance of Duolite ARA-9366 resins over Duolite A-171 resins under identical operational parameters.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 13; 63-76
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
O konieczności zmiany paradygmatu ochrony radiologicznej – Komentarz SARI – Stowarzyszenia Uczonych dla Rzetelnej Informacji o Promieniowaniu
On the Need to Replace the Present Paradigm of Radiation Protection - Comments by SARI (Scientists for Accurate Radiation Information)
Autorzy:
Dobrzyński, L.
Janiak, M. K.
Strupczewski, A.
Waligórski, M.
Powiązania:
https://bibliotekanauki.pl/articles/214587.pdf
Data publikacji:
2017
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
system ochrony radiologicznej
hipoteza LNT
hormeza radiacyjna
niskie dawki i moce dawki (LDDR)
reakcje immunologiczne
zdrowie publiczne
zdarzenia radiacyjne
radiofobia
Radiation Protection System
LNT hypothesis
radiation hormesis
low doses and dose rates (LDDR)
immune reactions
public health
nuclear accidents
radiophobia
Opis:
W jednym ze swoich pierwszych aktów wykonawczych, Prezydent Donald Trump zalecił „uwolnienie obywateli Stanów Zjednoczonych od nadmiernie uciążliwych norm i regulacji”. W odpowiedzi, Amerykańska Agencja Ochrony Środowiska (EPA) zaapelowała o propozycje, które uczyniłyby regulacje dotyczące ochrony radiologicznej „mniej uciążliwymi”. Stowarzyszenie Uczonych dla Rzetelnej Informacji o Promieniowaniu (SARI) przesłało do EPA swój Komentarz w tej sprawie, w którym proponuje, aby odrzucić hipotezę liniową bez progu dawki (Linear No-Threshold, LNT) jako podstawę przepisów ochrony radiologicznej i zastąpić ją przez hormezę - dobroczynne działanie niskich/o niskiej mocy dawek promieniowania jonizującego, uruchomiających naturalne mechanizmy obronne w organizmie człowieka, głównie poprzez pobudzenie takich reakcji jak usuwanie rodników tlenowych, naprawę DNA i funkcje immunologiczne. Oparcie przepisów ochrony radiologicznej na hormezie radiacyjnej doprowadzi do poprawy zdrowia ogółu ludności i znacznego obniżenia kosztów społecznych ochrony przed promieniowaniem oraz ograniczy negatywne skutki ewentualnych awarii jądrowych. Tekst Komentarza SARI został przetłumaczony, aby umożliwić polskiemu czytelnikowi zapoznanie się z tym krótkim, ale wnikliwym przeglądem proponowanego systemu ochrony radiologicznej, opartego o zjawisko hormezy radiacyjnej, wraz z naukowym uzasadnieniem powodów, dla których należy odrzucić obecny paradygmat tego systemu - hipotezę LNT.
By one of his first Executive Orders, President Trump established the “policy of the United States to alleviate unnecessary regulatory burdens placed on the American people.” Acting on this order, the US Environmental Protection Agency (EPA) solicited comments on making radiation protection regulations “less burdensome.” In response, SARI (Scientists for Accurate Radiation Information) submitted to EPA a document proposing that the (Linear No-Threshold, LNT) hypothesis on which radiation protection regulations are presently based should be rejected and replaced by hormesis – the beneficial action of low doses and low dose rates (LDDR) of ionizing radiation, predominantly due to activation of natural defence mechanisms of the body such as scavenging of reactive oxygen species, up-regulation of DNA repair, and boosting of immune reactions. Basing radiation protection regulations on radiation hormesis will benefit the health of the public, significantly decrease the public costs of radiation protection and reduce the adverse impact of any future nuclear accidents. The text of the SARI document has been translated to provide the Polish reader with a brief but comprehensive review of the proposed hormesis-based system of radiation protection and with science-based arguments for rejecting its present LNT paradigm.
Źródło:
Postępy Techniki Jądrowej; 2017, 3; 2-11
0551-6846
Pojawia się w:
Postępy Techniki Jądrowej
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-10 z 10

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies