• Title/Summary/Keyword: Radiations

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Detection and Measurement of Non-ionizing Radiations (비전리방사선의 검출 및 측정)

  • Lee, Jai-Ki
    • Journal of Radiation Protection and Research
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    • v.20 no.3
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    • pp.155-162
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    • 1995
  • The state-of-the art of detection and measurements of non-ionizing radiations are reviewed in relation to protection requirements, especially for electromagnetic and ultraviolet radiations. Dosimetric quantities, instruments and considerations needed for measurement are briefly explained. For electromagnetic radiation, the power density levels from various practical sources are summarized for reference uses. Large errors remain in the measurements of non-ionizinf radiations in general. Technical needs of development in measurement and dosimetry of non-ionizing radiations, therefore, are promissing when the increasing public concerns about the adverse health effects of non-ionizing radiations and proliferation of their uses are taken into account.

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Sensitivity and uncertainty quantification of neutronic integral data in the TRIGA Mark II research reactor

  • Makhloul, M.;Boukhal, H.;Chakir, E.;El Bardouni, T.;Lahdour, M.;Kaddour, M.;Ahmed, Abdulaziz;Arectout, A.;El Yaakoubi, H.
    • Nuclear Engineering and Technology
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    • v.54 no.2
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    • pp.523-531
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    • 2022
  • In order to study the sensitivity and the uncertainty of the Moroccan research reactor TRIGA Mark II, a model of this reactor has been developed in our ERSN laboratory for use with the N-Particle MCNP Monte Carlo transport codes (version 6). In this article, the sensitivities of the effective multiplication factor of this reactor are evaluated using the ENDF/B-VII.0, ENDF/B-VII.1 and JENDL-4.0 libraries and in 44 energy groups, for the cross sections of the fuel (U-235 and U-238) and the moderator (H-1 and O-16). However, the quantification of the uncertainty of the nuclear data is performed using the nuclear code NJOY99 for the generation and processing of covariance matrices. On the one hand, the highest uncertainty deviations, calculated using the ENDFB-VII.1 and JENDL4.0 evaluations, are 2275, 386 and 330 pcm respectively for the reactions U235(n, f), $ U_{235}(n\bar{\nu})$ and H1(n, γ). On the other hand, these differences are very small for the neutron reactions of O-16 and U-238. Regarding the neutron spectra, in CT-mid plane, they are very close for the three evaluations (ENDF/B-VII.0, ENDF/B-VII.1 and JENDL-4.0). These spectra present two peaks (thermal and fission) around the energies 0.05 eV and 1 MeV.

Trichel Pulse in Negative DC Corona discharge and Its Electromagnetic Radiations

  • Zhang, Yu;Liu, Li-Juan;Miao, Jin-Song;Peng, Zu-Lin;Ouyang, Ji-Ting
    • Journal of Electrical Engineering and Technology
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    • v.10 no.3
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    • pp.1174-1180
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    • 2015
  • We investigate in this paper the radiated electromagnetic waves together with the discharge characteristics of Trichel pulse of negative DC corona discharge in air in pin-to-plate and wire-to-plate configurations. The feature of the current pulse and the frequency spectrum of the electromagnetic radiations were measured under various pressures and gas gaps. The results show that the repetition frequency and the amplitude of Trichel pulse current depend on the discharge conditions, but the rising time of the pulse relates only to the radius of needle or wire and keeps constant even if the other conditions (including the discharge current, the gas gap and the gas pressure) change. There exists the characterized spectrum of electromagnetic waves from negative corona discharge in Trichel pulse regime. These characterized radiations do not change their frequency at a given cathode geometry even if the averaged current, the gas gap or the air pressure changes, but the amplitude of radiations changes accordingly. The characterized electromagnetic radiations from Trichel pulse corona relate to the formation or the rising edge of current pulse. It confirms that the characterized radiations from Trichel pulse supply information of discharge system and provide a potential method for detecting charged targets.

NTP-ERSN verification with C5G7 1D extension benchmark and GUI development

  • Lahdour, M.;El Bardouni, T.;El Hajjaji, O.;Chakir, E.;Mohammed, M.;Al Zain, Jamal;Ziani, H.
    • Nuclear Engineering and Technology
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    • v.53 no.4
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    • pp.1079-1087
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    • 2021
  • NTP-ERSN is a package developed for solving the multigroup form of the discrete ordinates, characteristics and collision probability of the Boltzmann transport equation in one-dimensional cartesian geometry, by combining pin cells. In this work, C5G7 MOX benchmark is used to verify the accuracy and efficiency of NTP-ERSN package, by treating reactor core problems without spatial homogenization. This benchmark requires solutions in the form of normalized pin powers as well as the vectors and the eigenvalue. All NTP-ERSN simulations are carried out with appropriate spatial and angular approximations. A good agreement between NTP-ERSN results with those obtained with OpenMC calculation code for seven energy groups. In addition, our studies about angular and mesh refinements are carried out to produce better quality solution. Moreover, NTP-ERSN GUI has also been updated and adapted to python 3 programming language.

Attitudes on the Use of Radiations in Some College Students (일부 대학생의 방사선이용에 대한 태도)

  • Han, Eun-Ok;Lee, Joon-Il
    • Journal of Radiation Protection and Research
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    • v.31 no.4
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    • pp.219-235
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    • 2006
  • Based on the fact that studies on the use of radiations have not been largely conducted reflected on the importance of the use of radiations, the survey was performed to investigate the attitude on the use of radiations for some university students who have a high level of knowledges among average persons in order to extract certain directions for the education program to provide right information. The survey was performed for 517 university students from Oct. 10 to Oct. 15, 2005. The results of this survey can be summarized as follows. 1. Students who have experienced in the radiation related education presented statical differences in the results according to the majoring and monthly incomes. 2. Regarding the survey on the attitude of the use of radiations, the item of 'I agree to build a general hospital or university hospital where I lives in' was presented as the highest points of $3.73{\pm}1.004$, and the lowest point was recorded in the item of 'I agree to build an atomic wastes treatment facility where I live in' as the point of $2.63{\pm}1.091$. 3. The level of attitudes on 'I agree to build an atomic power plant or atomic wastes treatment facility where I live in' presented lower levels than that of the attitude on 'I agree to build an atomic power plant or atomic wastes treatment facility in my country'. 4. The lowest level recorded in the level of attitudes on 'I agree to build an atomic wastes treatment facility where I live in 'presented a significant difference according to the sex and grade.

Knowledges, consciousnesses, and attitudes of some university students on the use of radiations (일부 대학생의 방사선이용에 대한 지식, 의식도 및 태도)

  • Han, Eun-Ok;Park, Byung-Sub
    • Journal of Radiation Protection and Research
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    • v.30 no.4
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    • pp.221-230
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    • 2005
  • This study attempts to extract certain directions for the education program to provide right information by investigating knowledges, consciousnesses, and attitudes of some university students. They have a high level of knowledges among average persons on the use of radiations in order to recognize the radiation safety in daily lives including the change in national recognitions for radiations safety that is consistent with the situation in these days. The survey was performed for 528 university students from Oct. 10 to Oct. 15, 2005. The results of this survey can be summarized as follows; students who didn't get educations for the use of radiations were recorded as 415 students (80.7%) in which the reason that they didn't get such educations was there were no chances to receive the education' as 265 students (77.9%). The basic knowledge on the use of radiations was presented as a low level of $5.96{\pm}2.90$ points based on the sum of 15 points, and the consciousness on the use of radiations was investigated as $3.65{\pm}0.50$ points based on the sum of 5 points. In addition, the attitude on the use of radiations was investigated as $3.23{\pm}0.46$ points based on the sum of 5 points.

Synthesis, physical, optical and radiation shielding properties of Barium-Bismuth Oxide Borate-A novel nanomaterial

  • B.M. Chandrika;Holaly Chandrashekara Shastry Manjunatha;K.N. Sridhar;M.R. Ambika;L. Seenappa;S. Manjunatha;R. Munirathnam;A.J. Clement Lourduraj
    • Nuclear Engineering and Technology
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    • v.55 no.5
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    • pp.1783-1790
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    • 2023
  • Barium Bismuth Oxide Borate (BBOB) has been synthesized for the first time using solution combustion technique. SEM analysis reveal flower shape of the nanoparticles. The formation of the nanoparticles has been confirmed through XRD & FTIR studies which gives the physical and chemical structure of the novel material. The UV light absorption is observed in the range 200-300 nm. The present study highlights the radiation shielding ability of BBOB for different radiations like X/Gamma rays, Bremsstrauhlung and neutrons. The gamma shielding efficiency is comparable to that of lead in lower energy range and lesser than lead in the higher energy range. The bremsstrauhlung exposure constant is comparably larger for BBOB NPs than that of concrete and steel however it is lesser than that of lead. The beauty of BBOB nanoparticles lies in, high absorption of radiations and low emission of secondary radiations when compared to lead. In addition, the neutron shielding parameters like scattering length, absorption and scattering cross sections of BBOB are found to be much better than lead, steel and concrete. Thus, BBOB nanoparticles are highly efficient in absorbing X/Gamma rays, neutrons and bremsstrauhlung radiations.

4th Generation Light Source: X-ray Free Electron Laser (4세대 방사광: 엑스선 자유전자레이저)

  • Han, Jang-Hui
    • Vacuum Magazine
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    • v.3 no.4
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    • pp.4-7
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    • 2016
  • An X-ray Free Electron laser facility (PAL-XFEL) has been built in Pohang Accelerator Laboratory to provide X-ray FEL radiations for photon users. The machine consists of a 10 GeV normalconducting S-band linear accelerator and two undulator beamlines. The hard and soft X-ray beamlines will provide FEL radiations with wavelengths of 0.6 to 0.1 nm and 4.5 to 1 nm, respectively. Beam commissioning of PAL-XFEL is ongoing and user service will start in 2017. In this report, the PAL-XFEL layout and the working principle are discussed.

Application of Radiations for Random Noise (형광물질의 방사선을 응용한 Random Nois)

  • J. K. Lee
    • 전기의세계
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    • v.13 no.3
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    • pp.8-12
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    • 1964
  • The study of the research for Random process have been recently increasing rapidly. There are many methods in generating of Random signal, however, mainly these are dependent upon utilizing of hot noise of resistance and noise of discharge tube. Consequently, it is not easy to obtain of Random Noise of stabilized low frequency. Therefore, I like to study over the result of principle and design in the method of obtaining the Random Noise with faint radiations of fluoresence materials.

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Dose metrology: TLD/OSL dose accuracy and energy response performance

  • Omaima Essaad Belhaj;Hamid Boukhal;El Mahjoub Chakir;Meryeme Bellahsaouia;Siham Belhaj;Younes Sadeq;Mohammed Tazi;Tahar El Khoukhi;Maryam Hadouachi;Khaoula Laazouzi
    • Nuclear Engineering and Technology
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    • v.55 no.2
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    • pp.717-724
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    • 2023
  • An essential step in evaluating and comparing the performance of two passive radiation dosimeter types, thermosluminescent (TLD) and optically stimulated luminescence (OSL), used by workers in environments with ionizing radiation for individual radiological monitoring and control of external exposure at various times (cumulative dose for 1 month), is to compare the measured dose accuracy, energy response, and coefficient of variation. In fact this performance study consists in determining the accuracy of both R(10) and R(0.07) which are considered as the ratios of the measured dose (Hp(10) or Hp(0.07)) to the delivered dose (Hp(10) or Hp(0.07)) for each photon energy. The validity of the results of this test is based on the acceptance limits of the ICRP and the international standard IEC-62387. The relative energy response used is normalized to the 137Cs 662 keV energy to find which energy response is closest to the ideal case, and the coefficient of variation that allows to determine the statistical fluctuation of the Hp(10) and Hp(0.07) doses. The results of the accuracy test for the OSL and TLD dosimeters are acceptable because they fall within the ICRP limits. For the energy response, the OSL performs better than the TLD for Hp(10) and Hp(0.07), and for the coefficient of variation, the OSL satisfies the requirements of ISO 62387 for both Hp(10) and Hp(0.07), while the TLD satisfies these requirements only for the measurement of Hp (0.07).