Atom Indonesia (E-Journal)
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Analysis of Radiation Exposure Level on Linen and Other Objects in Patient Rooms at Nuclear Medicine Installation
Full text linkAnalysis of radiation contamination levels has been carried out using an Atomtex surveymeter in the patient rooms after thyroid cancer ablation therapy, in the Nuclear Medicine Installation, Abdoel Wahab Sjahranie Hospital. This study aims to measure the level of radiation exposure based on the rate of radiation exposure and radiation contamination of objects in the patient rooms after ablation therapy, and to find out how long linen can be washed since the first measurement. Data collection was carried out once a week, on the same weekday, for five weeks for objects in the patient rooms by using the surveymeter at a fixed distances from the objects’ surfaces. Radiation contamination measurements for linen items were carried out for 3 d by aiming the surveymeter to container containing linen items from certain distances. Based on this study, the level of radiation exposure obtained is categorized as low because the value range is below 10 μSv/h. The radiation contamination for some objects are categorized as low-level exposure because the value is less than 3.7 Bq/cm2. Other objects tend to be in the moderate-level category because the value is more than 3.7 Bq/cm2 and less than 37 Bq/cm2. The values obtained refer to the standard issued by BATAN. It can be concluded that the patient rooms in the Nuclear Medicine Installation of Abdoel Wahab Sjahranie Hospital are safe
Ʌ-Hypernuclear States as Dihadronic Molecules
No full textThe study of exotic hypernuclei attracts a great deal of interest in nuclear physics. The reality of heavy hyperon hypernuclei is the subject of intense concern among theoreticians and experimenters in recent years. The core-hyperon model uses to explain abnormal nuclei spectra, recent observations of new exotic heavy hyperon hypernuclei cannot be explained or predicted by ordinary heavy core nuclei. These exotic hypernuclei states are a two-cluster bound states. We calculate the mass spectrum and constituent mass of particles in hypernuclei using the relativistic Schrödinger equation with molecular pseudoharmonic-type potential between particles inside the core and hyperon. Such calculations represent the interaction between the hyperon and the nuclei core. I review recent theoretical studies on the ground states and the excited states of hypernuclei bound states. Finally, we present explicit predictions of the exotic bound states based on the interactions obtained from quantum field theory and the projective unitary representation model. Studies have shown that by increasing the mass number of hyperon-core states, the value of the constituent mass and energy eigenvalue of Ʌ-hypernucleus increases. Also, by growing and increasing the proton number in the (Ʌ-N) states the value of the constituent mass of Ʌ-hyperon increases
Assessment of Computed Tomography Dose Index (CTDI) During CT Pelvimetry Using Monte Carlo Simulation
Full text linkA pelvimetry examination is sometimes prescribed to a pregnant woman at the end of her pregnancy in order to assess the dimensions of her pelvis prior to childbirth. This examination has long been performed by using X-ray, but is now increasingly being replaced by CT-scan The objective of this study is to assess the radiation doses received during a practical CT pelvimetry examination performed using a Hitashi Supria 16-slice CT scanner. The radiation doses were estimated using Monte Carlo (MC)-based simulation with GATE code to model the 16-slice CT scanner machine. The GATE code operates using GEANT4 libraries. A polyymethyl metacrylate (PMMA) acrylic phantom of 32 cm diameter was modeled to represent the patient's body. X-ray energy spectrum generated using the SRS-78 spectrum processor was used for simulation. The simulation was executed with the same exposure parameters as the practical CT pelvimetry examination with dose parameters of 1 mGy, 0.9 mGy, and 36.6 mGy.cm, respectively, for the weighted CT dose index (CTDIw), the volume CT dose index (CTDIvol), and dose-length product (DLP). The MC simulation results provide dose parameters of 1.16 mGy, 1.07 mGy, and 43.6 mGy.cm, respectively, for the CTDIw, CTDIvol, and DLP. The differences between the simulation and the practical examination were 16 %, 18 %, and 18 %, respectively. These differences are considered in a quite good agreement. The results were also consistent with other similar studies. This work proves that the Monte Carlo simulation with the GATE code is usable to assess the patient doses during a CT pelvimetry examination
A Modified Method for Increasing Radiochemical Purity of I-125 for Radiopharmaceuticals
Full text linkIodine-125 (125I) is one of the radioisotopes widely used in radiopharmaceuticals for diagnosis and therapy of various cancers. Recent reports indicate that there has been shortages in the world supply of this radioiodine isotope. One of the absolute requirements good radiopharmaceuticals must meet is radiochemical purity, which generally has to be above 95 %, with an efficiency of over 90 %. The previous investigation shows that the radiochemical purity is low and does not meet the radiochemical requirement. In this work, we aim at improving the previous method by modifying the Jones reductor-based method. The modified method includes reduction and uniformization of Zn particle sizes, Zn particle compaction, and the performance of reduction process in a closed process flow. The Jones reductor converted impurities into products; in this case, iodate (IO3-) and periodate (IO4-) impurities were converted into iodide (I-), so that 125I product fulfills the radiochemical purity requirements and yielded high efficiency. In this investigation, the 125I previous product was, for the first time, improved with a radiochemical purity of 99.24 % and an efficiency of 97.98 %
Radon Concentration in Urban Areas in the North and West of Morocco
Full text linkRadon is a colorless, odorless radioactive gas produced by the decay of uranium and radium. It is the second cause of cancer of the lungs after smoking. It has been present in Earth's crust since the creation of Earth. Uranium-rich rocks in the deep crust are the main source of radon. Its emanation from the ground surface varies from one point to another depending on the physical characteristics of the terrain crossed as observed in this study between North and West Morocco. A dosimetric study of those emanations was performed by using the LR-115 solid-state nuclear track detector (SSNTD) which was subsequently processed by techniques developed and calibrated in the laboratory. The study revealed high concentrations of this gas in confined spaces at ground level and, in particular, in basements and less-ventilated ground floor rooms. In order to reduce these concentrations of radon and the probability of carcinogenic attacks by these accumulations of this gas, it is recommended to ventilate these premises well. Good air circulation allows the removal of this harmful gas
External Bremsstrahlung Studies on Films of Lead Monoxide Filled Polycarbonate Composite
Full text linkThe development of high-Z (high atomic number) radiation shielding materials is vital in order to protect personnel who work with harmful gamma radiation sources. At the same time, the emission of external bremsstrahlung (EB) radiation in those shielding materials when the radiation source emits beta particles as well as gamma radiation is also of prime concern.The production of EB in films of lead monoxide (PbO) loaded polycarbonate (PC) composite at eleven different filler levels (FLs) varying, in terms of weight fraction, from 0.0 % up to 10.0 % were investigated experimentally by using beta particles from strontium-90/yttrium-90 (90Sr/90Y) radioactive source. A nonlinear relation is observed between EB intensity and target thickness. The effective atomic numbers of the prepared PbO-filled PC composite films (at different FLs) were determined via EB measurements, followed by calculations, and the values obtained were compared with the modified atomic numbers which were determined for the same composite films (at different FLs) using the Markowicz and Van Grieken equation, and it was found that they are in good agreement. Finally, the atomic number dependence of EB in these composite films (PbO-filled PC composites) has been studied. It is obtained that the intensity of EB spectra depends on the square of the atomic number of the target material
Analytical Studies on the Radionuclide Levels of Sediment and Water in an Agricultural Environment in the Egyptian Delta
Full text linkThis paper is an environmental investigation of the concentration values of radioisotopes and hazardous elements, aimed to shed light on industrial pollution and the effect of using fertilizers in the period of irrigation water drainage from cultivated lands, especially in the River Nile, irrigated, and draining channels in the middle portion of the Egyptian river delta. Different samples were analyzed, both for water and sediment. Many physical and chemical characteristics of samples were investigated. Among them are the quantitative measure of the acidity or basicity of aqueous or other liquid solutions (pH), grain size, and the total organic matter content (TOM) have been determined for sediments. pH and TDS, beside other types of pollutants, were determined for water samples. The water and sediment samples pH are slightly alkaline. The mean value of TDS for water samples is 488 mg/l, while he usual TDS value in river is 500 mg/l. The TOM values show that the sediment samples are poor in organic matter content. The bicarbonate range in the water samples is smaller than the same range in river water. The levels of Ra-226, Th-232, and K-40 activity in sediments are highly correlated. Natural radionuclides seem to correlate with the artificial Cs-137 in sediment. For this peruse, a 240 cm3 high-purity germanium reagent Type-B was used to quantify the levels in each sample with a relative accuracy of 50 %. The radioactive element K-40 is having a typical value of 12.5 Bq/kg. The concentrations of both Cu beside Zn in water samples is smaller if compared with values that quoted by the WHO, the US-EPA, and the EC. It was also found that the average levels for both Cd and Mn are found to be close to the internationally recommended levels. The water and sediments in the southern part of the canal contain higher concentrations of heavy metals and radioactive isotopes than in the rest of the canal
Determination of the Diagnostic Reference Level (DRL) in Samarinda Hospitals
Full text linkThe diagnostic reference level (DRL) is a form of investigative level used as a tool to help optimize protection to radiation exposure for diagnostic and interventional procedures. The purpose of this study was to determine the local DRL values for the examination of the abdomen, thorax, and head at radiology installations. The modality used was 128-slice CT scan. The numbers of patients whose data were used were 200 for abdominal examinations, 160 for thoracic examinations, and 100 for head examinations. Overall, the total patient whose data was used was 460. Data processing in this study was carried out with a quantitative analysis technique, namely descriptive statistics. This analysis technique used secondary data obtained from the results of recaptures or archival books for examination of the abdomen, thorax, and head. Data processing was carried out with a measure of diversity through the calculation of the third quartile in the data distribution. It was assumed that 75 % of patients performed examinations with a common diagnosis. The results of these calculations are visualized in the form of graphs of the relationship of computed tomography dose index volume (CTDIvol) with the number of patients and a graph of the relationship of dose length product (DLP) with the number of patients. In the abdominal examination, a CTDIvol of 12 mGy and a DLP of 1545.5 mGy·cm. In the thoracic examination, a CTDIvol of 11 mGy and a DLP of 903 mGy·cm were obtained. For the head examination, a CTDIvol of 34.25mGy and a DLP of 2190.25 mGy·cm were obtained. The conclusion obtained from this study is that the DRLs are relatively low, but they still need to be optimized by medical physicists