Atom Indonesia (E-Journal)
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On the Temperature Dependence of the Rate Constant of the Bimolecular Reaction of Two Hydrated Electrons
Get PDFIt has been a longstanding issue in the radiation chemistry of water that, even though H2 is a molecular product, its “escape” yield g(H2) increases with increasing temperature. A main source of H2 is the bimolecular reaction of two hydrated electrons (e-aq). The temperature dependence of the rate constant of this reaction (k1), measured under alkaline conditions, reveals that the rate constant drops abruptly above ~150°C. Recently, it has been suggested that this temperature dependence should be regarded as being independent of pH and used in high-temperature modeling of near-neutral water radiolysis. However, when this drop in the e-aq self-reaction rate constant is included in low (isolated spurs) and high (cylindrical tracks) linear energy transfer (LET) modeling calculations, g(H2) shows a marked downward discontinuity at ~150°C which is not observed experimentally. The consequences of the presence of this discontinuity in g(H2) for both low and high LET radiation are briefly discussed in this communication. It is concluded that the applicability of the sudden drop in k1 observed at ~150°C in alkaline water to near-neutral water is questionable and that further measurements of the rate constant in pure water are highly desirable.Received:13 June 2013; Revised: 27 August 2013; Accepted: 28 August 201
Physicochemical and Biological Analysis of 99mTc-Glutathione Radiopharmaceuticals
Get PDF99mTc-glutation (99mTc-GSH) radiopharmaceutical is available in the GSH lyophilized-kit in which ready to use directly after adding 99mTc radionuclide. In nuclear medicine, 99mTc-GSH diagnostic kit is a radiopharmaceutical commonly utilized for cancer diagnoses using imaging method. This paper described the physicochemical and biological characteristics as well as the quality of 99mTc-GSH diagnostic kit prepared from the GSH lyophilized-kit. The radiochemical purity was determined with thin layer chromatography (TLC) method, performed on a TLC-SG stationary phase with a mobile phase of a dried acetone and 0,9% of NaCl solution. Studies on the effect of volume and radioactivity of Na99mTcO4 solution to the radiochemical purity of 99mTc-GSH were carried out. The sterility of GSH-lyophilized kit and toxicity of 99mTc-GSH were also investigated. The stability test on GSH lyophilized kit and 99mTc-GSH in several storage conditions, as well as the plasma stability of 99mTc-GSH was performed. The analysis result showed that the GSH lyophilized-kit was sterile; the 99mTc-GSH was non toxic with 99.54 ± 0.01% of radiochemical purity and remained stable 5 hours either at room temperature or 4 oC. The volume more than 4 mL of Na99mTcO4 solution on the labeling of GSH could decreased the 99mTc-GSH radiochemical purity, while the radioactivity more than 20 mCi in 7 mL of volume extended the incubation time. In-vitro stability test of 99mTc-GSH in plasma showed that in the two hours of storage, the radiochemical purity decreased to 51.84 ± 2.52%, and until 5 hours of storage it did not change significantly. From the result, it can be concluded that the GSH lyophilized-kit was remained stable after 13 month of storage either at room temperature or at 4 oC with 99% of 99mTc-GSH radiochemical purity.Received: 16 January 2013; Revised: 23 August 2013; Accepted: 24 August 201
Reduction of Radioactive Waste Through the Reuse and Recycle Policy of the Sealed Radioactive Sources Management
Get PDFIn the past few years, the utilization of sealed source for medical, industrial and research purposes has shown an accelerating increase. This situation will lead to increases in the amount of sealed radioactive. During its use, a sealed radioactive waste will eventually become either a spent sealed source or disused sealed radioactive source (DSRS), due to certain factors. The reduction of the amount of radioactive waste can be executed through the application of reuse and recycle of sealed source. The reuse and recycle policy for spent and disused sealed sources are not already specified yet. The reuse of spent sealed sources can be applied only for the sources which had been used in the medical field for radiotherapy, namely the reuse of a teletherapy Co-60 source in a calibration facility. The recycle of a spent sealed source can be performed for radioactive sources with relatively high activities and long half-lives; however, the recycling activity may only be performed by the manufacturer. To avoid legal conflicts, in the amendment to the Government Regulation No.27 Year 2002 on Management of Radioactive Waste, there will be a recommendation for a new scheme in the management of radioactive waste to facilitate the application of the principles of reduce, reuse, and recycle.Received: 20November 2010; Revised: 11 June 2012; Accepted: 30 August 201
Bacterial Protein Characterization of Streptococcus agalactiae by SDS-page Method for Subclinical Mastitis Irradiated Vaccine Materials in Dairy Cattle
Get PDFA study have been conducted to isolate and characterize bacterial protein S. agalactiae, which is antigenic and can be used to test immunogenicity of vaccine in order to manufacture irradiated mastitis (inflammation of the udder) vaccine in ruminant. The study aims to determine the Molecular Weight (MW) bacterial protein S. agalactiae irradiation, which can be used to test the nature of its antigenic caharacteristic. The character of S. agalactiae antigenic stimulates antibody induction of the immune system, in which case is the body's defense system against mastitis disease in cattle. In this study, irradiation of gamma ray is used to attenuate the pathogenicity of bacteria by reducing S. agalactiae antigenic caharacteristic. Previous research, in irradiation dose orientation before antigenic protein isolation of S. agalactiae, indicated that irradiation lethal dose to 50% (LD50) is 17 Gy. The characterization of S. agalactiae bacteria isolate using SDS-page method results in no significance different between irradiated and non-irradiated group, which indicated by MW range 75 – 100 kDa base on marker standard which used, or 99 kDa by the linier equation of Y = 11,60 – 0.05X (where Y = bands distance; X = MW standard protein); r2 = 0.99. In conclusion, 17 Gy irradiation dose does not impair antigenic property of S. agalactiae and therefore, can be applied to produce base material of irradiated vaccine for mastitis. Received: 04 May 2012; Revised: 27 November 2012; Accepted: 27 August 201
Measuring the BNF of Soybean Using 15N-Labelled Urea with Different Atom Excess (A.E.) Content
Get PDFThe soybean is a legume which has an ability to supply its major nitrogen need by the biological nitrogen fixation (BNF) process. This process is made possible by nodules formed in their roots, colonized by Rhizobium sp.bacteria. An accurate estimation of N gained by BNF is necessary to predict the increase or decrease of chemical fertilizer-N requirements to increase soybean production. Among several methods, the 15N method was used to estimate the ability of legumes to perform BNF. The study involved soybean var. Willis (W) and a completely non-BNF soybean var. CV, which is termed as a standard crop. The standard crop is non-nodulated soybean, but it has the same main physiological traits with var. Willis. The aim of this study was to determine whether15N-labelled fertilizer with different %a.e. given to nodulated and non-nodulated soybean would not be of significant consequences for the calculation of N-BNF of W. The treatments applied were different rates of urea (20 kg N/ha and 100 kg N/ha) combined with different atom excess percentages (%a.e.)15N (2% and 10%). Thus, the combination of treatments were as follows:(1) W-ll (20 kg N; 2% a.e); (2) CV-hl (100 kg N; 2% a.e); (3) W-lh (20 kg N; 10% a.e); (4) CV-hh (100 kg N; 10% a.e); (5) CV-ll (20 kg N; 2% a.e); (6) W-hl (100 kg N; 2% a.e); (7) CV-lh (20 kg N; 10% a.e); (8) W-hh (100 kg N; 10% a.e). The result of the experiment showed that a high %a.e. with a low rate of 15N and a low %a.e. with a high rate of N should be used to study the %N-BNF of nodulated plants.Received: 16 March 2012; Revised: 14 December 2012; Accepted: 17 December 201
Development of a PIGE-Detection System for in-situ Inspection and Quality Assurance in the Evolution of Fast Rotating Parts in High Temperature Environment Manufactured from TiAl
Get PDFIntermetallic γ-titanium aluminides are a promising material in high temperature technologies. Their high specific strength at temperatures above 700°C offers the possibility for their use as components of aerospace and automotive industries. With a specific weight of 50% of that of the widely used Ni-based superalloys TiAl is very suitable as material for fast rotating parts like turbine blades in aircraft engines and land based power stations or turbocharger rotors. Thus lower mechanical stresses and a reduced fuel consumption and CO2-emission are expected. To overcome the insufficient oxidation protection the halogen effect offers an innovative way. After surface doping using F-implantation or liquid phase-treatment with an F-containing solution and subsequent oxidation at high temperatures the formation of a protective alumina scale can be achieved. By using non-destructive ion beam analyses (PIGE, RBS) F was found at the metal/oxide interface. For analysis of large scale components a new vacuum chamber at the IKF was installed and became operative. With this prototype of in-situ quality assurance system for the F-doping of manufactured parts from TiAl some performance test measurements were done and presented in this paper.Received: 01 March 2013; Revised: 24 April 2013; Accepted: 25 April 201
Clinical Application of Renograph IR-03 for the Hospital
Get PDFThe renography using renograph is one of clinical modality to investigate the renal function among other such as laboratory medical check up and X-rays. The prototype of renograph IR-03 designed by BATAN has been constructed and the laboratory tests as well as clinical tests have been carried out at PRPN-BATAN Serpong and General Hospital Dr. Sardjito Jogyakarta, respectively. Cost associated with the clinical use of renograph at the hospital are analyzed according to the two major components: radiopharmaceutical cost and the use of equipment. Annual cost of operational of renograph by estimate number of patient is about 2,000 is IDR. 30.0 millions for radiopharmaceutical 131Iodine. Total Direct Cost is about IDR. 212.5 millions and the Capital Cost for one unit renograph is IDR. 250 millions. The Break Event Point of invest one unit renograph is 1194 procedures (0.597%), or about IDR. 209,475 millions, which the cost for each procedure is IDR. 85,000.-. This value is depending on several variables, especially number of procedure can be reached. The cash flow analyses by Rate of Return (ROR) showed that the value of i* is 22.6% is much greater than the value of MARR or saving rate of interest in the Bank now is about 10%. The Payback Period calculation to see on how interesting the investment of renograph and its prospect for application in the hospitals showed about 1.818 years, that is good prospect economically. Received: 28 April 2011; Revised: 03 July 2012; Accepted: 07 July 201
Comparison of Gamma Irradiated and Raw Lignite in Bioliquefaction Process by Fungus T5
Get PDFThe bioliquefaction of coal is a processing technology for converting solid coal to liquid oil at ambient temperature by helping microorganism. The pretreated of lignite is important to decrease the hydrofobic of lignite surface. One of pretreated method was irradiation by gamma rays. Aim of this research was to compare the gamma irradiated lignite and raw lignite in bioliquefaction process by selected fungus T5. The fungus was identified by molecular method using 18S rDNA. Treatments were A (MSS + gamma irradiated lignite 5% + T5) and B (MSS + raw lignite 5% + T5) and culture type was sub-merged. The parameters observed were colonization, bacterial and fungal enumeration, identify of dominant bacteria using 16S rDNA and characterization of bioliquefaction product by UV-Vis spectroscopy dan gas chromatography – mass spectrometry (GCMS). The results showed that fungus T5 belongs to Ascomycota, Trichoderma asperellum. Fungus has the ability to growth and liquefy gamma irradiated and raw lignite. Bacteria were detected in raw lignite treatment and dominant bacteria were identified as Bacillus megaterium and Bacillus thuringensis. UV-Vis analysis showed that boliquefaction product mainly contained naphtacene, naphthalene, and anthracene for gamma irradiated lignite, but anthracene and benzene for raw lignite. For GCMS analysis, 22 and 38 compounds were identified for gamma irradiated and raw lignite. Both treatment had different number of hydrocarbon, i.e. C6 – C35 (A) and C10 – C35 (B) and dominated by aromatic acids, aliphatic and phenylethers. Percent area of gasoline (C7 – C11) and diesel (C10 – C24) fractions on the treatment B was 7.23% and 62.35%, while in treatment A was 7.22% and 44.27%. Based on the results, pretreated of lignite by gamma irradiation could be increased the bioliquefaction product.Received: 5 December 2011; Revised: 21 May 2012; Accepted: 11 June 201
Stopping Powers and Inelastic Mean Free Path of 100 eV to 30 keV Electrons in Zirconium Silicates
Get PDFWe have determined the electron stopping power (SP) and inelastic mean free path (IMFP) of (ZrO2)x(SiO2)1-x (x=1, 0.75, 0.5, 0.25, 0) for electron energies from 100 eV to 30 keV by means of modified Born–Ochkur equations. The energy loss function (ELF) is required in the calculation of SP and IMFP. We used the electron energy losses from 0 to 80 eV obtained by quantitative analysis of reflection electron energy-loss spectroscopy (REELS) spectra. The values of SP and IMFP for high contents of ZrO2 (x=50% and x=75%) in Zr-silicates are similar to those of ZrO2, and similar to those of SiO2 for low contents of ZrO2 (x=25%) in Zr-silicates. There are small differences in the values of SP and IMFP for ZrO2 and SiO2.We found that the SP decreases while the IMFP increases with increasing electron energy. We have demonstrated that the ELF obtained from the quantitative analysis of REELS spectra provide us with a straightforward way to determine SP and IMFP for alloy materials by using modified Born-Ochkur equations. Received: 04 December 2012; Revised: 18 December 2012; Accepted: 19 December 201
Y-Spect: A Multi-Method Gamma Spectrometry Analysis Program
Get PDFTo accomplish a more accurate, precise and correct interpretation and analysis of spectrum data collecting from a gamma spectrometry counting system, a fully interactive computer code, named Y-Spect, has been developed by using the Delphi 7.0 programming language. The code combines several popular methods for peak search, i.e.: Mariscotti, Phillips-Marlow, Robertson et al., Routti-Prussin, Black, Sterlinski, Savitzky-Golay and Block et al. Any combinations of those methods can be chosen during a peak searching process, which can be performed in automatic or manual mode. Moving Window Average- and Savitzky-Golay-methods are available for spectrum data smoothing. Peak fitting is done by using a non-linear least square method of Levenberg-Marquardt for either a pure Gaussian peak shape or one with an additional Right/Left Tail function. Other than standard features, such as: peak identification and determination of: continuum, region of interest (ROI), and peak area, etc., Y-Spect has also a special feature which can predict the existence of escape- and/or sum peaks that belong to a certain radioisotope. Aside from displaying the complete spectrum graph, including: singlet or multiplet ROIs and peak identifications, Y-Spect can also display the first- or second-derivative of the spectrum data. Data evaluation is given as: isotope names, peak energy, Net-Count(-Rate), etc. Y-Spect is provided with a complete ENDF/B-VII.0 gamma-ray library file that contains of 16089 gamma energy lines from 1420 different radioisotopes. Other general specifications are: maximum number of: spectrum's channels = 16*1024; ROIs = 2*1024; ROI’s width = 2*1024 channels; Overlapping peaks (multiplet) = 20; Identified isotopes = 3*1024, and Isotope library's energy lines = 16*1024.Received: 16 January 2013; Revised: 21 April 2013; Accepted: 25 April 201