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Nuclear batteries based on silicon carbide betavoltaic cells have been studied extensively in the literature. This paper describes an analysis of design parameters, which can be applied to a variety of materials, but is specific to silicon carbide. In order to optimize the interface between a beta source and silicon carbide p-n junction, it is important to account for the specific isotope, angular distribution of the beta particles from the source, the energy distribution of the source as well as the geometrical aspects of the interface between the source and the transducer. In this work, both the angular distribution and energy distribution of the beta particles are modeled using a thin planar beta source (e.g., H-3, Ni-63, S-35, Pm-147, Sr-90, and Y-90) with GEANT4. Previous studies of betavoltaics with various source isotopes have shown that Monte Carlo based codes such as MCNPX, GEANT4 and Penelope generate similar results. GEANT4 is chosen because it has important strengths for the treatment of electron energies below one keV and it is widely available. The model demonstrates the effects of angular distribution, the maximum energy of the beta particle and energy distribution of the beta source on the betavoltaic and it is useful in determining the spatial profile of the power deposition in the cell. [ABSTRACT FROM AUTHOR]

Monte Carlo computer simulation of beta radiation transport within radioactively-contaminated food samples was studied and compared with experimental results. We used the Monte Carlo code PENELOPE-2008. The basic geometry of a hand-held contamination monitor and the geometry of beta-emitting food samples and surface sources were modeled, and the detection efficiency of the device was determined. Possibilities to improve the detection efficiency were tested by simulation. [ABSTRACT FROM AUTHOR]

We describe an attempt at the development of an in situ detector for beta ray measurements in underwater environment. The prototype of the in situ detector is based on a CaF2: Eu scintillator using crystal light guide and Si photomultiplier. Tests were conducted using various reference sources for evaluating the linearity and stability of the detector in underwater environment. The system is simple and stable for long-term monitoring, and consumes low power. We show here an effective detection distance of 7 mm and a 2.273 MeV end-point energy spectrum of 90 Sr/ 90 Y when using the system underwater. The results demonstrate the feasibility of in situ beta ray measurements in underwater environment and can be applied for designing an in situ detector for radioactivity measurement in underwater environment. The in situ detector can also have other applications such as installation on the marine monitoring platform and quantitative analysis of radionuclides. [ABSTRACT FROM AUTHOR]

In this study thin LiF:Mg,Cu,P dosimeters (trade name MCP-Ns) designed for measurements in beta radiation fields were tested in comparison with classical LiF:Mg,Cu,P ones (trade name MCP-N). The readout stability as well as TLD response in low (∼kBq) and high (∼MBq) radioactivity fields (beta and beta-gamma) were verified. The stability of MCP-Ns decreased during first 10 complete measuring cycles and then detectors appeared to be stable. Unfortunately, around 60 th cycle the stability was lost. In the MCP-N group the stabilization was observed from 20th cycle but it was maintained in further measuring cycles. The MCP-Ns response in low radioactivity fields (∼kBq) was difficult to verify (dose values oscillated around the “zero dose reading”), reliable results were observed for high radioactivity fields (∼MBq). The dose measured by MCP-Ns was ten times higher in beta fields and around five times higher in mixed beta-gamma fields in comparison to the MCP-N. MCP-Ns seems to be adequate and more sensitive to measure beta dose or mixed beta-gamma dose, however the uncertainty of a single measurement has to be under more careful control compared to MCP-N which have higher repeatability and stability. [ABSTRACT FROM AUTHOR]

Beta radioisotope energy sources, such as tritium ( 3 H), have shown significant potential in satisfying the needs of a sensor-driven world. The limitations of current beta sources include: (i) low beta-flux power, (ii) intrinsic isotope leakage and (iii) beta self-absorption. The figure of merit is the beta-flux power ( dP β /dS in μW n /cm 2 ), where an optimal portion of incident beta particles penetrates the semiconductor depletion region. Thus, the goal of this research was to identify a compound to contain a beta emitter that can permit beta-flux power of at least 0.73 μW n /cm 2 from one side, where it can be used for both planar and textured semiconductor structures. Nitroxides were chosen because of previous demonstrated deuteration, ease of synthesis, diversity of structure, and pliability. As a proof-of-principle, nitroxide [ 1 ] was prepared and tritiated with a specific activity of 103 Ci/g. The corresponding tritiated nitroxide in toluene was found to have no measurable 3 H 2 outgassing after 27 days, thus it was considered stable. After 256 days in solution, analysis of the compound showed only 2% tritium loss, whereas in solid form, there was approximately 50% of tritium loss after 21 days. To compare with the performance of a typical metal tritide carrier, the standard MCNPX Monte Carlo code was used to calculate the beta-flux power of tritiated nitroxide and titanium tritide (0.2 μW n /cm 2 and 0.70 μW n /cm 2 ), respectively. The difference between numerical and empirical results of titanium tritide was 4%, showing the model validity. For the tritiated nitroxide to be comparable to titanium tritide in a planar configuration (2-D), the gravimetric density ( 3 H weighted percentage) would need to be at least 9%. [ABSTRACT FROM AUTHOR]

The classical over-barrier ionization model (COBI) method and trajectory calculations were utilized to simulate the ionization of He impacted by a positron. The calculated ionization cross sections of He agree with other theoretical data. Additionally, we found that the double ionization of He has a definite association with the positron-He impact. This result can explain why doubly ionized He seemed to be positron-scattered by the rest of the He in our previous study. The COBI model was also extended to study the double ionization caused by positron-Ne impacts. Our theoretical results agree with the experimental data. Graphical abstract: [ABSTRACT FROM AUTHOR]

The prevalent algorithm for the estimation of beta dose, which in turn is used for estimation of skin dose for exposures involving beta radiations was observed to significantly overestimate the dose in individual monitoring based on CaSO4:Dy TLD badge in India. A new algorithm has been developed by estimating the correction factor from the response of dosemeter to different beta sources at various angles of incidence. The correction factor was observed to vary linearly with the ratio of the responses of dosemeter element without filter (D3) and dosemeter element under Perspex filter (D2). The correction factor determined using the ratio of D3 and D2 was applied to the response (D3) of dosemeter element without filter for estimation of beta dose. Protocol for identification of beta in the mixed gamma beta fields was defined such that it resulted in nearly same correction factor for given beta source in both gamma beta mixed fields and pure beta fields. The beta dose evaluation algorithm has provided the beta dose estimation within the required accuracy for >90% cases obtained from national quality assurance test data from different laboratories. [ABSTRACT FROM AUTHOR]

In this work, we report the dosimetric characterization and the evaluation of the kinetics parameters of trapping states of ZnO phosphors obtained thought a chemical route. Pellet-shaped samples present thermoluminescence (TL) properties suitable for use as radiation detectors and dosimeters. The glow curve is composed of three peaks with the maxima at about 412, 530 and 600 K. The last peak is located into the temperature range considered most suitable for TL dosimetry applications. The activation energies and the frequency factors of trapping states involved in the TL emission were evaluated using the initial rise method, peak shape methods, and glow curve deconvolution (GCD). The values of the activation energies obtained using peak shape methods agree with those computed from GCD. [ABSTRACT FROM AUTHOR]

Purpose: The absorbed doses for two radioisotopes, 99mTc and 131I, between previously validated Zubal phantom and the recently developed XCAT phantom were compared. Materials and methods: GATE Monte Carlo code was used to simulate the statistical process of radiation. A XCAT phantom with voxel and matrix sizes similar to a standard Zubal phantom was generated. According to Medical International Radiation Dose formalism, specific absorbed fraction (SAF) values for photons and S-factors for beta particles were tabulated. The amounts of absorbed doses were calculated and compared in different organs. Results: The differences of gamma radiation doses, SAFs, between Zubal and XCAT are >50% in adrenal from adrenal, pancreas from pancreas and thyroid from thyroid, in lung from kidney, kidneys from lungs and in kidneys from thyroid and thyroid from kidneys. The beta radiation doses differences between Zubal and XCAT are >50% in thyroid from thyroid, bladder from bladder, kidney from kidney, liver from bladder, thyroid from bladder and kidney from thyroid. The size and distances of the organs were different between XCAT and Zubal phantoms. Denoted differences of SAF and S-factors correspond to the different organ geometries in phantoms. Conclusion: The results of absorbed doses in Zubal and XCAT phantoms are different. The variations prohibit easy comparison or interchangeability of dosimetry between these phantoms. [ABSTRACT FROM AUTHOR]

The results for the comparison of Hp(0.07, 0°) in 90Sr/90Y, carried out by the SSDL-ININ (pilot) and CPHR, are presented. Four calibration curves (CCs) are constructed with 32 TLD-200 dosimeters irradiated on a PMMA phantom. The CCs, TLD's Response RTLD (nC) vs Hp(0.07, 0°), are in the range 0.2-100 mSv. The SSDL-ININ rate Hp(0.07, 0°) value is (43.85 ± 0.57) µSv s-1 obtained with a primary extrapolation chamber serial 040. These same dosimeters are irradiated at the CPHR with a rate of Hp(0.07, 0°) = (14.94 ± 0.36) µSv s-1, also calibrated with another primary standard extrapolation chamber serial 105. After irradiation at CPHR, the dosimeters are returned to the SSDL-ININ for reading, and then irradiated again to construct the fourth CC (CC4). The comparison is based on a modification of the standard ANSI/HpS N13.11-2009, where the reference values are [Hp]ININ,ref. For the values of [Hp]CPHR the statistics bias B = 0.002; standard deviation, S = 0.099; and tolerance level L = 0.099 are determined. The homoscedasticity test is performed for the variances associated to the mean performance quotient B. [ABSTRACT FROM AUTHOR]

To better understand the distribution of deposited energy of beta and gamma rays according to changes in shielding materials and thicknesses when radionuclides are used for therapeutic nuclear medicine, a simulation was conducted. The results showed that due to the physical characteristics of each therapeutic radionuclide, the thicknesses of shielding materials at which beta-ray shielding takes place varied. Additional analysis of the shielding of gamma ray was conducted for radionuclides that emit both beta and gamma rays simultaneously with results showing shielding effects proportional to the atomic number and density of the shielding materials. Also, analysis of bremsstrahlung emission after beta-ray interactions in the simulation revealed that the occurrence of bremsstrahlung was relatively lower than theoretically calculated and varied depending on different radionuclides. [ABSTRACT FROM AUTHOR]

An intercomparison of eye lens dosemeters has been conducted in terms of the quantity Hp(3). For the first time, besides photon radiation also beta radiation qualities were included. Three dosemeter types designed for the quantity Hp(3) and ten for Hp(0.07) took part in the intercomparison. As shown in a previous intercomparison for photon radiation only, the dosemeters designed for Hp(0.07) and calibrated in terms of Hp(3) performed well in photon radiation fields. But for beta radiation, it turned out that Hp(0.07) dosemeters over-responded up to a factor of 5 000 (with respect to the true Hp(3) dose) in the medium beta energy range (85Kr with a beta endpoint energy of 0.69 MeV), while some Hp(3) dosemeters performed quite well. For medium (57 keV) and high (662 keV) energy photon radiation, all dosemeter types showed response values well within the trumpet curve according to the current draft of ISO 14146. [ABSTRACT FROM AUTHOR]

Traditional fixed-filter radon progeny monitors are usually clogged with the loading of dust and cannot be used for radon progeny continuous measurement for long period. To solve this problem, a step-advanced filter (SAF) monitor for radon progeny measurement was developed. This monitor automatically roll and stop the filter at each interview. Radon progeny is collected on a 'fresh' filter at a flowrate of 3 L/min. At the same time, alpha and beta particles emitted from filter are recorded by a PIPS detector. A newly developed alpha-beta spectrum method was used for radon progeny concentration calculation. The 218Po, 214Pb and 214Bi concentrations as well as equilibrium equivalent concentration (EEC) could be worked out at the same time. The lower level limit detection of this monitor is 0.48 Bq m-3 (EEC) for 1h interval. Comparison experiments were carried out in the radon chamber at the National Institute of Metrology of China. The measurement results of this SAF monitor are consistent with EQF3220 (SARAD GmbH, Germany), and the uncertainty is smaller. Due to its high sensitivity, the periodical variation of radon progeny concentration can be easily observed by this monitor. The SAF moniter is suitable for continuous measurement in both indoor and outdoor environments. [ABSTRACT FROM AUTHOR]

Glioblastoma is one of the lethal brain tumors and one of the resistant tumors against radiotherapy. Multiple treatment methods and different types of radiation and Radiosensitizers drugs have been combined to optimize the efficacy of radiotherapy. Radiosensitizers are employed to reinforce tumor cell killing and have much fewer effects on the normal tissue. Inducing DNA double strand break in tumoral cells is a major goal of radiation sensitivity. In this study, the level of DNA double strand break in glioblastoma spheroids irradiated by 2 Gy beta particles of iodine-131 and 6 MV X-rays in the presence of 2-Methoxyestradiol (2ME2), iodo-deoxy-uridine (IUdR) and Topotecan (TPT) was measured using the PicoGreen method. Spheroids of the U87MG cell line were cultured to reach a 300 µm diameter. In the phase one of the study, the spheroids were treated in four groups individually, including 2 Gy of iodine-131, TPT+iodine-131, IUdR+iodine-131, IUdR+2ME2+iodine-131. In the next phase, the cells were treated with 2 Gy of 6 MV X-ray, TPT+6 MV X-ray, IUdR+6 MV X-ray, TPT+IUdR+6 MV X-ray. DSB lesions were measured by the Pico Green assay. The amount of DSB lesions in groups irradiated with iodine-131 individually was greater than the group irradiated with 6 MV X-ray (p<0.05). DNA double strand breaks became more significant in combination with TPT. However, the amount of DSBs in the two independent groups of TPT+IUdR+2ME2+iodine-131 and TPT+IUdR+2ME2+6 MV X-ray was approximately in the same range (P>0.05). The level of DNA double strand breaks in cells irradiated with Iodine-131 was higher than cells irradiated with 6 MV X-ray at the same dose and Topotecan had a positive effect on inducing the damage. The role of 2ME2+IUdR in increasing the damage caused by beta particles of iodine-131 was not significant. Iodine-131 could lead to major DSB damage than 6 MV X-ray at the same dose due to its cross fire effect and spatial distribution of energy in different angels. This study showed that a combination of chemotherapy and iodine-131 had better efficacy than radiotherapy with 6 MV X-ray in the treatment of glioblastoma. [ABSTRACT FROM AUTHOR]

Calcium Sulfate (CaSO 4 ) is one of the most investigated materials used as Thermally Stimulated Luminescence Dosimeter (TLD). It has been experimentally modified with several dopants to increase/modify its Thermoluminescent (TL) sensitivity. Mn (Manganese) doping in CaSO 4 being the first to be investigated. CaSO 4 : Mn inspite of high sensitivity, lost its popularity due to its high fading (40–85% in the first 3 days after exposures). Another potential limitation in the use of this material was its sensitivity to light. We have attempted to turn its limitation to its advantage by discovering its Opticaly Stimulated Luminescence (OSL) properties. Till now no study has been reported in this material for its OSL characteristics. This paper investigates the preliminary studies CaSO 4 :Mn as a new material for OSL dosimetry. The irradiation was carried out from Sr-90 (beta) and Cs-137 (gamma) sources. Synthesis was carried out by recrystallization method using Calcium sulfate with concentrated sulfuric acid. Formation of the compound was confirmed by the X-ray diffraction (XRD) study. In addition to the study of variation of dose (beta and gamma) on the OSL signal, effect of light induced fading, effect of excitation source, effect of power and time on stimulation signal, effect of thermal and optical annealing have also been examined and reported. The paper also explores the dependence of temperature on the OSL intensity popularly known as Thermally Assisted OSL (TA–OSL) which showed a correlation between the TL and OSL traps. Theoretical analysis of OSL curves for three excitation sources were performed in order to have a deeper understanding of the OSL phenomena. OSL response to a wide range of beta and gamma doses of CaSO 4 :Mn and excellent reusability confirm its suitability as an effective OSL material and explore its potential for tremendous applications in radiation dosimetry. [ABSTRACT FROM AUTHOR]

Rapid determination of gross alpha and beta emitters in urine by liquid scintillation counting is discussed. This method is based on direct addition of urine into scintillation cocktail. Am, Pu and Sr were selected as model radionuclides. The LSA Hidex 300 SL equipped with Triple-Double-Coincidence-Ratio technique was used for sample measurement. The work focused on optimizing the LSC cocktail to urine volume ratio with respect to the model radionuclides. The overall efficiencies for Am, Pu and Sr were greater than 92 %; therefore, this method would be suitable for rapid determination of gross alpha/beta activity. [ABSTRACT FROM AUTHOR]

Introduction: Targeted radionuclide therapy (TRT) has been demonstrated to be an effective therapeutic tool in patients with disseminated bone metastasis. TRT is generally performed with a single radionuclide. In this study we investigated the feasibility of combined TRT with a high-energy beta emitter (153Sm) and a low energy beta emitter (177Lu) in wistar rats. Methods: The cocktail complex of 153Sm/177Lu-EDTMP was prepared. To determine the effect of metal-to-ligand (Me:EDTMP) molar ratio on labeling yield, several complex were analyzed after changing Me:EDTMP molar ratio from 1:1 to 1:50. 153Sm/177Lu- EDTMP was administered intravenously through the tail vein of wistar rats. Biodistribution data were collected at 2 hours to 7 day post injection and scintigraphic images were taken at 24 hours and 1, 2 week after administration of radiopharmaceutical. Results: The results revealed high skeletal uptake (3.5% and 3.4% ID/g at 24 hours post injection for 153Sm and 177Lu, respectively) with rapid blood clearance and minimal uptake in any of the major organs. Scintigraphic images verified high skeletal uptake. Conclusion: Our results indicate that the combination of 153Sm and 177Lu is feasible and safe. This study suggests that the combination of different radionuclides with different radiation energies and half-life, such as 153Sm and 177Lu, could be advantageous in patients with tumoral lesions of different sizes. [ABSTRACT FROM AUTHOR]

Copper-64 was produced in large scales and high specific activities in late 1990s' using compact cyclotrons based by 64Ni(p,n)64Cu reaction and many radiopharmaceuticals developed since then by various groups based on interesting physicochemical and nuclear properties of the radionuclide. The unique emission of beta particles as well as positron particles offers a spectacular real therapeutic/diagnostic ("Theranostic") radionuclide in nuclear medicine. Although the development of copper-64 radiopharmaceuticals continued with a slower rate in 2010s' due to availability of 68Ga-tracers, however recent advances in application of therapeutic doses of 64Cu has emerged a new trend in the radiopharmaceutical development based on coppe-64. In this review, recent advances in the copper-64 theranostic radiopharmaceuticals including introduction of new chelating groups with enhanced stability as well as radiolabelling conditions as well as application of simple 64CuCl2 radiopharmaceutical as areal theranostic agent in human subjects are summarized. A proposed strategy for development of peptide based copper-64 radiopharmaceuticals with high and low dose therapeutic applications has been suggested. [ABSTRACT FROM AUTHOR]

A new version of the Iranian Noble Gas Analyzing System (INGAS) has been improved to facilitate measurement of beta-gamma coincidence events. It employs a new prototype list-mode multi-parameter data analyzer system, MPA4300. In order to test the new version performance, it has used to obtain energy spectra from radioxenon isotopes using the detector assembly of the Iranian Noble Gas Analyzing System. The MPA4300 is able to set the coinciding parameters, extract the corresponding spectrum, and through the use of event by event list file, can replay the measurement in offline mode. A great novelty of this work is the use of internal timing circuit in MPA4300 instead of using standard pick up time modules to identify coincidence events of detectors. A detailed description of the measuring 222 Rn and 131 m Xe is presented. [ABSTRACT FROM AUTHOR]

Highly optical transparent tellurite glasses are attractive and viable as alternative materials for absorbing gamma-ray photons in the design of radiation protection structures. This report examines the potential of new tellurite glass systems (TeO 2 -ZnO-WO 3 -Bi 2 O 3) doped with Er3+ (TZWB-Er), Tm3+ (TZWB-Tm), and Nd3+ (TZWB-Nd) as shielding materials against charged and uncharged radiation. The mass attenuation coefficient, μ / ρ of the glasses was computed by XCOM software and data from simulations of photon transmission in the PHIT code. The total stopping powers and range of beta particles β, H+, He2+, and C6+ in the glasses were estimated by ESTAR, PSTAR, ASTAR, and SRIM software at particle kinetic energies within 0.1–10 MeV. The fast neutron (FN) removal and thermal neutron absorption cross-sections in the glasses were also computed. The stopping powers and ranges of the considered charged particles showed variations that depended on the kinetic energy of the particles and chemical composition of the glasses. The TZWB-M glasses are better alternatives as gamma-radiation shields compared to traditional shielding substances such as concrete, some commercial glass shields, and recently recommended glass shields. The glasses are thus recommended for the design of radiation safety structures. [ABSTRACT FROM AUTHOR]

Aiming at improving reaction selectivity of zeolite Beta-catalyzed isomerization of normal alkane, we reported a facile but efficient route to prepare the Beta@SBA-15 composite supports with low surface diffusion barriers in isomers formation from normal alkane. Microporous Beta zeolite and mesoporous SBA-15 zeolite were physically mixed and milled by high-energy planetary ball-mill. The addition of SBA-15 and milling, which have little effect on the acid properties of Beta zeolites, disaggregate the Beta particles and anchor the Beta nanocrystals on the surface of SBA-15 mesostructure. The apparent diffusivities of 2-methyl pentane measured by zero-length column method increased by 50%. n -Hexane isomerization tests show that the Pt/Beta@SBA-15 catalysts exhibit much higher selectivity to isomers, especially the dibranched isomers and lower selectivity to cracking reaction, owning to the reduced transport limitation of composite supports. [Display omitted] • Beta@SBA-15 was facilely prepared by physical mixing and high-energy milling. • Milling disaggregates Beta particles and anchors Beta nanocrystals on SBA-15 surface. • Pt/Beta@SBA-15 exhibit much higher alkane isomerization selectivity. [ABSTRACT FROM AUTHOR]

In this work, we report the Persistent Luminescence (PLUM) of ZrO 2 :Tb3+ samples synthesized by a conventional solid-state reaction and its performance in radiation dosimetry. X-ray diffraction shows the formation of the monoclinic phase of ZrO 2 and the doping of the samples with Tb3+ ions and a mixture of Tb 2 O 3. The ZrO 2 :Tb3+ 1% sample was exposed to beta particle irradiation in a dose range from 0.5 to 256 Gy. Immediately after removing the beta particle source, the PLUM response was measured for 600 s. The integrated area of the PLUM decay curves shows a sublinear dependence in the dose range from 0.5 to 64 Gy. The TL glow curve of the ZrO 2 :Tb3+ 1% sample showed two maxima at 79 and 150 °C after beta particle irradiation, suggesting that the trapping states associated with the maximum at 79 °C are responsible for the PLUM at room temperature. Computational deconvolution showed that the maximum at 79 °C consisted of two traps with first-order kinetics. The results suggest that the ZrO 2 :Tb3+ 1% sample has potential applications as a dosimeter for beta particle irradiation. [Display omitted] • Luminescence Persistence of the ZrO2:Tb3+ 1% 600 s after beta particle irradiation is reported. • The Integrated PLUM decay curves show a sublinear dependence in the dose range from 0.5 to 64 Gy. • The lifetime τ were computed for each PLUM decay curves with bi-exponential fit. • TL glow curve of the ZrO2:Tb3+ 1% showed that the maximum at 79 °C consisted of two traps with first-order kinetics responsible for PLUM. [ABSTRACT FROM AUTHOR]

In the present work, we investigate the thermoluminescence (TL) and optically stimulated luminescence (OSL) from strontium molybdate SrMoO 4 powders designed with different capping agents. The samples were prepared through co-precipitation and processed in a Microwave-Assisted Hydrothermal (MAH) system. The structural, optical, and morphological characteristics were investigated using Raman, Fourier transform infrared spectroscopy (FTIR), DRX, ultraviolet-visible (UV–Vis) absorption, and Scanning electron microscopy (SEM). The TL glow curves recorded from as-prepared and irradiated samples with beta particles reveal that their intensity and profile depend on the used capping agent. The trapping depth energy, determined from the TL glows curves, ranges from 1.02 to 2.23 eV for the as-prepared samples and from 0.9 to 2.33 eV for the irradiated phosphors. The residual TL spectra, registered from successive readouts, indicate that the thermal treatment shifts the glow curve to lower temperatures suggesting the formation of shallower trap states. The outcomes reveal that the OSL signal and its behaviors with the radiation dose depend on the employed capping agent. The results show the TL and OSL signal's dependence on the structural properties and support the potential application of SrMoO 4 powders as an OSL detector. • SrMoO 4 powders were synthesized via co-precipitation and processed in a microwave-hydrothermal system. • The influence of different capping agents on the material properties was investigated. • The intensity and profile of the glow curves depend on the adopted capping agent. • The OSL signal exhibits a linear variation with the beta radiation dose for the samples designed with PEG400. [ABSTRACT FROM AUTHOR]

With the aid of thermoluminescence (TL), we have extensively studied YAl 3 (BO 3) 4 host matrices incorporat e d with Tb3+ at different doping contents, which have been produced by combustion. The measured the TL glow curves exposed to beta rays at different doses consisted of four broad peaks located at around 76, 126, 230, and 378 °C. The peak maximum of the 230 °C TL peak shifts toward higher temperatures after 5 Gy beta irradiation while the other peak maxima almost remain constant. It is peculiar that 230 °C peak maximum shifts to higher temperatures with increased radiation dose and can be attributed to the multiple phases of the sample. A TL glow curve exhibits a proportional increase in intensity with increased the heating rate. A discussion of the possible causes of this pattern is provided. Observed peaks using the T m ─ T stop method are due to the presence of a quasi-continuous distribution of traps. The parameters of the traps have also been estimated using various heating rate methods in excellent agreement with one another. • The effect of heating rate on the glow curve of YAl 3 (BO 3) 4 :Tb was studied. • The activation energy and the frequency factor were analysed using VHR method. • Peaks from Tm-Tstop are due to the presence of quasi-continuous distribution of traps. [ABSTRACT FROM AUTHOR]

This study aims to perform dosimetry and defect analysis of different Al concentrations in AZO after being irradiated for 91 days using 90Sr/90Y. Particle interaction was also simulated using MCNPX to confirm the effect of Al addition on the radiation dose received. AZO films were prepared using the sol-gel spin coating method with Al concentrations ranging from 0 wt%, 3 wt%, 6 wt%, and 9 wt%, while the structure was characterized with XRD and FTIR. The beta dose received for 91 days was calculated by direct measurement using a gamma survey meter and simulation by MCNPX, both culminating in the order of 102 Gy. The results showed that the damage to AZO crystallization increased with rising Al concentrations. Moreover, the deposited energy received by AZO increased with increasing concentrations of Al. The 9 wt% Al concentration caused the most significant damage to AZO crystallization compared to lower concentrations. • Al addition in ZnO increase the damage to AZO crystallization by beta radiation. • Deposited energy by beta particles was found to increase with Al addition in ZnO. • The absorbed dose was calculated using radiation dose measured by a survey meter. [ABSTRACT FROM AUTHOR]

An earlier publication "The implication of the atomic effects in neutrinoless double beta (0 ν β β) decay" written by Mei and Wei has motivated us to compare the decay Q value (Q β β) derived from the decay of the parent nucleus to the daughter nucleus with the two ejected beta particles in the final state to the Q β β directly derived from the decay of the initial neutral atom to the final state of double-ionized daughter ion with the two ejected beta particles in the final state. We show that the results are the same, which is the mass-energy difference (Δ M c 2) subtracted by the total difference of the atomic electron binding energy (Δ E b) between the ground states of initial and final neutral atoms. We demonstrate that Δ M c 2 is the sum of Q β β and the atomic relaxation energy (Δ E b) of the atomic structure after the decay. Depending on the atomic relaxation time, the release of the atomic binding energy may not come together with the energy deposition of the two ejected beta particles. [ABSTRACT FROM AUTHOR]

Introduction: Radiation is the emission of a particle or energy in waveform. This is known as electromagnetic radiation. Examples consist of radio waves, microwaves, ultraviolet and infrared lights, X-rays, and gamma rays. Radiation can be described as two basic types, ionizing and non-ionizing radiation. The three main kinds of ionizing radiation are alpha rays, beta rays, and gamma rays. Radioactive pollution has adverse effects when it comes to genetics. It leads to damage of DNA which leads to genetic breakdown in the course of time. Pregnant women exposed to radiations can give birth to children with adverse effects due to genetic mutations. Cancer is the most dominant disease caused due to radioactive pollution. Longterm exposure to heavy radiation causes cancer. Materials and Methods: A self-administered questionnaire was prepared based on radioactive pollution; its causes, health effects and circulated among 80 college students. The data were collected in SurveyPlanet and the results were statistically analyzed. Results and Discussion: About 91% of college students are aware of radioactive pollution. About 90% of students are aware of the three types of radiations. About 87% of students are aware that the effects of radioactive pollution can be passed down to future generations. 91% of students are aware that long time exposure to radioactive pollution can cause cancer. Conclusion: Radioactive pollution is due to the presence or depositions of radioactive materials in the atmosphere or environment, especially where their presence is accidental, presents an environmental threat. The destruction caused by the radioactive substances is due to hazardous ionizing radiations such as alpha, beta, and gamma. Cancer is the most dominant disease caused due to radioactive pollution. About 91% of college students are aware of radioactive pollution. [ABSTRACT FROM AUTHOR]

Radiation has negative deterministic and stochastic effects on the human body, such as decreased repairability of cells and DNA damage. In order to avoid the effects of exposure to external radiation, the need for shielding is also very important, along with observing the rules of time and distance. In this study, Ni–Co–B material was produced on steel substrates as an alternative to existing shielding materials, and hexagonal boron nitride was doped into these structures at different proportions. Structural and morphological properties of the produced materials were obtained with XRD and SEM images. Then, these samples were irradiated with alpha, beta, and gamma rays and their radiation attenuation properties were examined according to the current types in the production phase. To verify the results, stopping power and range values of the materials were calculated for the same beams. It was determined that the hexagonal boron nitride incorporating levels increased as one went from direct current to alternating current. The maximum incorporation level was approximately 1.1%. It was specified that the amount of boron in the material was directly proportional to the current intensity. It was observed that finer granular structures were formed under alternating current compared to direct current. It was found that gamma rays were absorbed the most and positrons were absorbed the least in the samples. According to the increasing hexagonal boron nitride ratios, the absorption percentages of alpha, electron, positron, and gamma rays varied as 0.13–3.75, 0.51–2.24, 0.015–1.04, and 0.72–8.37, respectively. As the hexagonal boron nitride ratios increased and changed from direct current to alternating current, both radiation absorption rates and stopping power increased. It was understood that gamma photons had a greater range in alternating current, and the range increased non-uniformly with the hexagonal boron nitride ratio. • Ni–Co–B/hBN structures were generated according to different production conditions. • These structures were irradiated with alpha, beta and gamma rays for shielding. • The absorption percentages increased from direct current to alternating current. • The absorption rates of the samples raised with the amount of hBN doped. • The findings were confirmed by the calculated stopping power and range data. [ABSTRACT FROM AUTHOR]

[Display omitted] • Interaction of beta particles with ECSs was simulated using Monte Carlo method. • ZrO 2 @Ar-TNRAs structure was used as the beta-anode of EBCs. • Photoelectrochemical performance was used to optimize the ECSs. • TiO 2 /ZrO 2 heterojunction with type-I band alignment can enhance the electrochemical redox reaction. Direct energy conversion from beta radiation to electricity using betavoltaic effect is a promising energy conversion technology for a long-time and highly efficient power supply. This work presents an electrochemical betavoltaic cell (EBC), consisting of a beta-anode with TiO 2 nanorod arrays (TNRAs) modified with ZrO 2 nanoparticles, a polyiodide (I −/ I 3 −) electrolyte, and a 63Ni/Ni counter electrode. Free-standing TNRAs structures were fabricated using hydrothermal method and post-annealed in Ar atmosphere to enable a rutile TiO 2 material with excellent electrochemical performance. Monte Carlo (MC) method was used to determine the optimum length (∼2.5 μm) of the TiO 2 nanorods. Investigation on ultraviolet photoelectrochemical performance of EBCs was used to evaluate and optimize the content of ZrO 2 (thickness of ∼10 nm) modified on the TNRAs. The EBCs demonstrated an energy conversion efficiency of 9.27% with an open-circuit voltage of 0.276 V and short-circuit current density of 1.041 μA·cm−2 when using a 10 mCi 63Ni source. The enhanced performance can be ascribed to the three-dimensional ZrO 2 /TiO 2 heterojunction with a large specific area in favor of the interface carrier transfer as well as the suppression of carrier recombination through the type-I band barrier, effectively promoting the electrochemical redox reaction. [ABSTRACT FROM AUTHOR]

Combination of two or three dissimilar scintillator materials as a radiation detector has found major role in environmental radiation monitoring. In this paper, a three-layer Phoswich detector including BC-400, YAG, and CsI was designed to efficiently discriminate gamma-ray in the beta events up to 3.2 MeV using a simple rise-time discrimination method. MCNPX Monte Carlo code was used to obtain interaction probability of beta and gamma-rays as well as optimum thicknesses of the layers in the designing process. The optical transport of the system was simulated by GEANT4. In this regard, the pulses from simultaneous beta-gamma emitter sources were detected and discriminated based on pulse's rise-time so that the minimum number of gamma-ray contaminating events was observed in the beta spectrum. The results showed that using the proposed configuration and the method, output pulses with a rise-time shorter than 9 ns have been successfully detected as a beta particle while those with rising time longer than 15 ns have been identified as gamma-ray events. Overall results revealed that using the proposed system, an individual spectrum of beta particles or gamma-rays can be recorded from a simultaneous beta-gamma emitter source that minimizes contribution of the other radiation. • A Phoswich detector was designed for simultaneous beta-gamma radiation. • Scintillator materials used in the detector structure should have different decay time constant. • GEANT4 simulation was used for scintillation lights transport. • A pulse discrimination method based on the pulse rise time has been proposed for pulse processing. • Beta-rays were successfully discriminated against gamma-rays by the proposed detector and associated pulse processing method. [ABSTRACT FROM AUTHOR]

In this work, we report the thermoluminescence (TL) response of a zeolite (Chabazite-Ca) from Divisaderos Sonora region northwestern Mexico and its performance in dosimetry applications. X-ray diffraction, scanning electron microscopy, and Energy Dispersive X-ray Spectroscopy were performed to obtain the structural, morphological, and elemental composition of the prepared zeolite samples. Zeolite samples were exposed to beta particle irradiation in the dose range from 5 to 7017 Gy. The TL glow curves of zeolite display a broad curve shape indicating the overlap of several TL glow peaks. The TL glow curve shows a maximum emission located at ∼174 °C and a prominent shoulder at 280 °C. The TL signal increases as the dose increase, keeping a linear dependence from 5 to up 690 Gy. A remarkable reproducibility of integrated TL response in 10 irradiation- TL readout cycles was observed, indicating zeolite samples are reusable. The fading signal is around ∼50 % in 3 days. The reported results suggest that Sonoran zeolites have potential applications as detectors and dosimeters for ionizing radiation. • TL response of a natural zeolite from Divisaderos, Sonora region in north-western Mexico. • Natural Zeolites thermally treated are very promising new solid state TL dosimeters. • The ZEOTT sample was exposed to beta particle radiation displayed linear behavior in the region of 5 up 690 Gy. [ABSTRACT FROM AUTHOR]

Direct reading survey meters, designed for the measurement of shallow dose rates, are commercially available. Examples of such instruments include the Fluke 451B, the BOT P200 m with SM20 probe, the Eberline RO-2A and the RAM-Ion. We investigated the potential use of these instruments, as eye lens dose rate meters, with the addition of low-Z filters of suitable thicknesses. Their responses to 90Sr/90Y beta particles and to photons of varied qualities, as functions of angles of incidence, were measured. It was determined that most instruments can be suitably modified to operate as useful eye-lens dose rate meters. Their use in the field could assist radiation protection professionals in the assessment of radiological risk to the lens of the eye. This will allow recommendations on appropriate PPE and dosimetry in individual workplace settings. • Four commercially available were tested for their accuracy in for the measurement of H p (0.07) and H p (3). • Radiation survey meters can be modified for the accurate measurement of H p (0.07) and H p (3) for photons and beta particles. • The addition of low-Z filters to the thin window of survey meters allows conservative estimates of H p (0.07) and H p (3). [ABSTRACT FROM AUTHOR]

Alpha contamination and high concentrations of beta contamination can be found inside the reactor buildings at the Fukushima Daiichi Nuclear Power Station (FDNPS). This study proposes a newly developed phoswich alpha/beta detector that can discriminate alpha and beta particles emitted from the alpha and beta contaminations in the FDNPS site. The phoswich alpha/beta detector is made up of two layers of scintillators that detect alpha and beta particles. The first layer is an octagonal, 50 mm diameter, 40-μm-thick plastic scintillator that measures alpha particles, while the second layer is an octagonal, 50 mm diameter, 50-μm-thick Gd₂Si₂O₇ (GPS) scintillator that measures beta particles. The combination of the two scintillators improves the ability to distinguish between alpha and beta particles. The two layers of scintillators were optically coupled to an 8 × 8 multianode photomultiplier tube (MA-PMT) with 50 mm × 50 mm through a 3-mm-thick light guide (glass plate). An eight-channel 14-bit 500 MS/s digitizer was fed with four output signals. Python programming was used to analyze the collected voltage waveforms. The pulse shape discrimination (PSD) method was used to detect alpha particles in high beta particle and high gamma-ray (comparable to gamma-ray dose rate near the FDNPS reactor building) environments. Due to a 23.3% full width at half maximum (FWHM) energy resolution for alpha particles, the detector can be used to distinguish between nuclear fuel materials such as plutonium and its radon progeny (Po-214). Moreover, the detector could distinguish alpha particles from 137Cs gamma rays with a dose rate background up to 9.0 mSv/h. It is the first to demonstrate that the developed phoswich detector can be used to discriminate and measure alpha and beta particles of the actual contaminated FDNPS samples. As a result, this detector will be effective as an air monitoring device for alpha and beta radionuclide contamination measurement in real time. • We developed a new alpha/beta phoswich detector for the Fukushima Daiichi Nuclear Power Station (FDNPS) site. • The first layer is a 40-µm-thick plastic scintillator, while the second layer is a 50-μm-thick Gd₂Si₂O₇ (GPS) scintillator. • The PSD method was used to detect alpha particles from high beta particle and high gamma-ray environments. • The developed phoswich detector can be used to discriminate and measure alpha and beta particles of the actual contaminated FDNPS samples. [ABSTRACT FROM AUTHOR]

Calcium Aluminate nanoparticles were prepared by the successful sol-gel route adopting hydrolysis of organometallic precursors. The crystalline properties, morphology, sample composition, and nanostructure of the as-synthesized samples were investigated by X-ray diffraction (XRD), Photoluminescence (PL), and Fourier transformer infrared (FTIR). Careful XRD analysis reveals the generation of orthorhombic CaAl 2 O 4 with 54.23 nm crystalline size. The prepared sample was irradiated with beta particles for different doses from 0.11 Gy to 330 Gy. The Thermoluminescence (TL) glow curves of the samples were deconvoluted using newly designed TL software. The deconvolution displayed 14 overlapping glow peaks composing the glow curves. The prepared samples have shown a linear beta dose response in the range of 11 Gy–330 Gy. The minimum detectable dose of the prepared samples was 262 μGy. The sensitivity and reproducibility of the TL response of the prepared samples were studied and were found to be very good. [Display omitted] • Calcium Aluminate nanoparticles were prepared by sol-gel. • The crystalline properties, morphology, and sample composition were investigated. • The TL glow curves of prepared samples were deconvoluted using new design TL software. • The prepared samples showed a linear beta dose response in the range up to 330 Gy. • The minimum detectable dose of the prepared samples was calculated as 262 μGy. [ABSTRACT FROM AUTHOR]

Microspheres for liver radioembolization for human use have high requirements in terms of their toxicity and biocompatibility on the one hand, but also typical properties such as physical and chemical durability or specific activity on the other hand. Developed manufacturing process based on the sol-gel method allowed to obtain spherical, yttrium trioxide grains of fully polycrystalline structure with diameters between 20 μm and 100 μm. The work is focused on a further investigation concerning the Y 2 O 3 microspheres including physical, radiometric, dosimetric, and biological experiments. Neutron activation analysis confirmed a high concentration of radioactive 90Y in the sample. The developed procedure for determining the specific activity of a single microsphere showed that at the time of administration, the activity can be specified at the level of 2600–3200 Bq per microsphere. FLUKA Monte Carlo code was used to prepare model for the calculation of dose distributions at the microscopic level, indicating that locally occurring heterogeneities can lead to cold spots during radioembolization. The data obtained from the simulation enabled analysis of the absorbed dose delivered by gel 90Y 2 O 3 microspheres as a function of radioactivity concentration, initial specific activity, or microsphere concentration in the sample. The reduction in colorectal cancer cell proliferation in vitro confirms the significant influence of beta ray radiation from yttrium-90 trioxide microspheres. Histopathological examination of the distribution of microspheres in the porcine model confirmed the proper location of yttrium trioxide microspheres inside blood vessels in a porcine model. Gel Y 2 O 3 microspheres manufactured using the sol-gel method showed relevant properties, indicating the possible use of microspheres for further biological and preclinical studies. • Gel Y 2 O 3 microspheres were manufactured using developed sol-gel method. • Specific activity was specified as 2500–3200 Bq per microsphere. • HCT116 cell proliferation was reduced in in-vitro experiment with Y 2 O 3 microspheres. • Histopathological examination proved proper location of the microspheres in tissue. • Monte Carlo-based model allowed to analyse the spatial distribution of microspheres. [ABSTRACT FROM AUTHOR]

This paper contains the results of studies into the possibilities and limitations of the use of UD-807 Panasonic dosimeters in extremity dosimetry. Detection efficiency, critical levels, detection limits, energy and angular dependence were determined with respect to the beta radiation emitted by 90 Sr| 90 Y and photon radiation in the range of 33 keV–662 keV. The calibration coefficients, expressed in units of personal dose equivalent H p (0.07), differed by no more than 10% for all types of radiation when the radiation reached the dosimeters at an angle of 0°. In other configurations, if the angle between the normal to the dosimeter surface and the radiation direction increased, the detection efficiency rapidly decreased - to a lesser extent in relation to the 33 keV photon radiation than to the beta radiation. The reduction was insignificant for photon radiation emitted by 137 Cs. [ABSTRACT FROM AUTHOR]

As a model for human tissue, this report considers the rate of free radical generation in a dilute solution of water in which a beta-emitting radionuclide is uniformly dispersed. Each decay dissipates a discrete quantity of energy, creating a large number of free radicals in a short time within a small volume determined by the beta particle range. Representing the instantaneous dissipated power as a train of randomly-spaced pulses, the time-averaged dissipated power p ¯ and rate of free radical generation g ¯ are derived. The analogous result in the theory of electrical circuits is known as the shot noise theorem. The reference dose of X-rays D ref producing an identical rate of free radical generation and level of oxidative stress is shown a) to increase with the square root of the absorbed dose, D, and b) to be far larger than D. This finding may have important consequences for public health in cases where the level of shot noise exceeds some noise floor corresponding to equilibrium biological processes. An estimate of this noise floor is made using the example of potassium-40, a beta-emitting radioisotope universally present in living tissue. [ABSTRACT FROM AUTHOR]

The U.S. Navy uses a dosimetric system, which employs the LiF:Mg,Cu,P thermoluminescence dosimeters (TLDs), developed and produced by Thermo Fisher Scientific. Every two years, the Naval Dosimetry Center (NDC) performs proficiency testing to maintain its national accreditation. Since 2007, the U.S. Navy has also tested InLight Basic - OSLN Optically Stimulated Luminescence Al 2 O 3 :C dosimeters (OSLD) manufactured by Landauer. In 2011 and 2013, the Naval Dosimetry Center performed proficiency testing for both systems. Here we present a comparison of the performance of TLDs (LiF:Mg,Cu,P) and OSLDs (Al 2 O 3 :C) in five categories of proficiency testing. The testing included irradiation with photons, neutrons, beta particles and selected mixtures of these radiations. All irradiations were performed at the Pacific Northwest National Laboratory (PNNL). The delivered doses were not reported to the NDC. The official comparison of delivered and reported doses was conducted by PNNL in terms of dose bias and its standard deviation for each category of accreditation. In total, the NDC reported to the PNNL doses for 147 dosimeters of each type (TLD and OSLD). Both NDC tested dosimetric systems have passed established limits. The comparison of OSLD and TLD system performance in each category is discussed. Advantages and disadvantages of both systems are analyzed. [ABSTRACT FROM AUTHOR]

Radiation processing of polymers is a well-established and economical commercial method of precisely modifying the properties of polymers, especially mechanical properties. The mechanical properties of modified low density polyethylene samples by beta rays were measured at the ambient temperature and after temperature load above the pure low density polyethylene melting temperature. The tested samples showed significant changes of mechanical behaviour before and after temperature load. From this point of view, new applications could also be seen in areas with service temperatures higher than their former melting point, especially for application with short time exposure of temperature load. [ABSTRACT FROM AUTHOR]

Introduction: In an African setting surgery is generally accepted as the treatment of first choice for glaucoma. A problem with trabeculectomy surgery for the glaucomas is the frequent co-existence and exacerbation of cataract. We report a randomized controlled trial to compare the use of beta radiation with 5FU in combined cataract and glaucoma surgery. Participants and Methods: Consenting adults aged >40 years with glaucoma, an IOP>21mmHG and cataract were enrolled and randomised to receive either 1000cG β radiation application or sub-conjunctival 5fluorouracil (5FU) at the time of combined trabeculectomy and phaco-emulsification with lens implant surgery. Results: 385 individuals were eligible for inclusion of whom 301 consented to inclusion in the study (one eye per patient). 150 were randomised to the 5FU arm and 151 received β radiation. In the 12 months following surgery there were 40 failures (IOP>21mmHg) in the 5FU arm and 34 failures in the beta arm. The hazard ratio for the beta radiation arm compared to the 5FU arm, adjusted for IOP at baseline, was 0.83 (95% c.i. 0.54 to 1.28; P = 0.40). The improvement from mean presenting visual acuities of 0.91 and 0.86 logMAR to 0.62 and 0.54 in the 5FU and beta arms respectively was comparable between groups (P = 0.4 adjusting for baseline VA). Incidence of complications did not differ between the two groups. Discussion: This study highlights several important issues in the quest for a therapeutic strategy for the glaucomas in an African context. Firstly, there is no evidence of an important difference between the use of 5FU and beta radiation as an anti-metabolite in phacotrabeculectomy. Secondly phacotrabeculectomy is a successful operation that improves visual acuity as well as controlling IOP in a majority of patients. Although the success of trabeculectomy in lowering IOP is reduced when combined with phacoemulsification compared with trabeculectomy alone, this finding has to be set against the possible need for subsequent cataract surgery following trabeculectomy alone, which represents a second trip and expense for the patient and results in 10–61% failure of the trabeculectomy at one year post-cataract surgery. Trial Registration: ISRCTN Registry [ABSTRACT FROM AUTHOR]

In the present paper, the formation of bremsstrahlung spectra by ordinary bremsstrahlung (OB) and polarization bremsstrahlung (PB) in metallic targets by 35 S beta particles has been investigated in the photon energy region of 1–100 keV. From the experimental measurements and the theoretical results obtained from Elwert corrected (non-relativistic) Bethe Heitler (EBH) theory, modified Elwert factor (relativistic) (F mod BH) theories for OB and Avdonina and Pratt (F mod BH+PB) theory for total bremsstrahlung (BS) having the contribution of PB into OB, it has been found that the contribution of PB into BS in a target is limited to a low energy region only and also varies with the atomic number of target material. The F mod BH+PB theory is in agreement with the experimental results in low energy regions of the target, whereas at high energy region F mod BH is found to give better agreement. Further, the present experimental results indicate that the screening effects in the Coulombic bremsstrahlung process cannot be neglected in the high energy region, and the multiple scattering and secondary electron emissions effects in thick target are required to be taken into account in describing the bremsstrahlung process. [ABSTRACT FROM AUTHOR]

A separation study using a 176 Yb target for the preparation of nca 177 Lu, which is a beta-emitting nuclide used not only in radioimmunotherapy applications but also in the treatment of various lesions, has been performed. A material having a better selectivity and separation efficiency for Lu than Yb was developed, and the separation conditions of 177 Lu were derived using this from a neutron irradiated 176 Yb target. The separation material was an organo-ceramic hybrid material containing a phosphate group. Adsorption behavior was determined through batch experiments, and 177 Lu separation from the Yb target was evaluated through column experiments. The Yb target, with a 99.72% in 176 Yb, was irradiated in the irradiation hole of HANARO, which has a thermal neutron flux of 1.6E+14 n cm −2 s −1 . The batch experiments revealed that the organo-ceramic hybrid material (Sol-POS) had a separation factor of 1.6 at 0.5 M HCl. Separation was performed through extraction chromatography using a 5 mg enriched Yb target, and the separation yield of the NCA 177 Lu was about 78%. If the amount of Yb target is increased to produce curies level 177 Lu, additional purification will be needed. [ABSTRACT FROM AUTHOR]

In this research gas sealed Multi-Wire Proportional Counter (MWPC) including blades between anode wires and beta particles of 90 Sr with 196 keV mean energy were considered. Ten different gases such as Noble gases mixtures with methane and several other pure gases were studied. In this type of detector, by using Garfield and Maxwell codes and for each of the gases, variation of different parameters such as first Townsend, electron attachment coefficients with variable electric field and their effects on pulse height or collected charge and in turn on Signal to Noise Ratio (SNR) were studied. Also the effect of anode voltage and its diameter and the pressure of gas on the pulse height were studied. Results show that Garfield and Maxwell codes can be used to study and improve the design of other gaseous detectors. [ABSTRACT FROM AUTHOR]