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Vol.18, No.4
SYNCHROTRON TECHNOLOGY AND APPLICATIONS
Research article 20 Aug 2007
LI Lin,SHEN Liren,ZHU Qing,WAN Tianmin
Accelerator database stores various static parameters and real-time data of accelerator. SSRF (Shanghai Synchrotron Radiation Facility) adopts relational database to save the data. We developed a data retrieval system based on XML Web Services for accessing the archive data. It includes a bottom layer interface and an interface applicable for accelerator physics. Client samples exemplifying how to consume the interface are given. The users can browse, retrieve and plot data by the client samples. Also, we give a method to test its stability. The test result and performance are described.
keywordXML;Web Service;Interface;Database;.NET;EPICS;AO;
LOW ENERGY ACCELERATOR, RAY TECHNOLOGY AND APPLICATIONS
Research article 20 Aug 2007
JING Chunguo,XING Guangzhong,LIU Bin
Online measurement of water volume fraction (WVF) in dehydrated crude oil is a difficult task due to very little water in dehydrated crude oil and high precision requirements. We presents a method to measure water volume fraction in dehydrated crude oil with γ-ray densitometry. The Monte Carlo computer simulation packet GEANT4 was used to analyze the WVF measuring sensitivity of the γ-ray densitometry at different γ-ray energies, and effects of temperature, pressure, salinity and oil components on WVF measurement. The results show that the γ-ray densitometry has high sensitivity in γ-ray energy ranges of 16~25keV, and it can distinguish WVF changes of 0.0005. The calculated WVF decreases about 0.0002 with 1℃ of temperature increase and they have approximately linear relation with temperature when water volume fraction remains the same. Effects of pressure, salinity and oil components on water volume fraction can be neglected. Experiments were done to analyze sensitivity of the γ-ray densitometry. The results , as compared with simulations, demonstrate that simulation method is reliable and it is feasible to gauge low water volume fraction using low energy γ-rays.
keywordWater volume fraction;Dehydrated crude oil;Gamma ray densitometry;Monte Carlo method;Compensation algorithm;
Research article 20 Aug 2007
R. RAVISANKAR,P. ESWARAN,N.P. SESHADERSSAN,Bramaji RAO
Element profiles of some beach rock samples collected from South East Coast of Tamilnadu, India have been determined using single comparator method of INAA. The geo-chemical behavior of the elements in the region is discussed. The irradiations were done at thermal neutron flux of ~ 1011 cm-2•s-1 at 20kW power using Kalpakkam Mini Reactor (KAMINI), IGCAR, Kalpakkam, Tamilnadu, India. Around 19 elements have been determined from 15 samples by high-resolution gamma spectrometry. The accuracy and precision were evaluated by assaying the irradiated Standard Reference Material (SRM 1646a Estuarine sediment) and were found to be in good agreement with certified values.
keywordBeach rock;Analysis;Instrumental neutron activation analysis;KAMANI Reactor;
Research article 20 Aug 2007
Hasan M. KHAN,Abdul MAHMOOD
Industrialization has led to a number of environmental problems, such as release of toxic metals and other toxic organic and inorganic compounds to the environment. Among all, the rapid expansion of leather related industries in Pakistan have resulted in considerable environmental problems and effluents from processing of both domestic and imported hides and skins have increased pollution to alarming levels. Some tannery effluents of Peshawar area investigated in the present study showed high concentrations of Cr(VI) (2.7-12.6 mg/L), Cu(II) (2.6-11.4 mg/L) and phenol (0.1-4.2 mg/L). These contaminants are very toxic and must be removed from effluents before releasing into water bodies. A new technique of gamma irradiation has been investigated to decrease the load of COD and concentrations of Cr(VI), Cu(II) and phenol associated with tannery effluents to the permitted values. It was observed that concentration of Cr(VI) in the effluents can be brought to the permitted level by applying radiation dose of 3 kGy. A radiation dose of 2.5 kGy was required to remove more than 95% of Cu(II) and 100 % degradation of phenol in tannery effluents could be achieved by only one kGy of radiation dose.
keywordRadiation induced decontamination;Tannery effluents;Cr(VI);Cu(II);Phenol;
RADIOCHEMISTRY, RADIOPHARMACEUTICALS AND NUCLEAR MEDICINE
Research article 20 Aug 2007
LEI Bei,ZHU Junqing,LU Chunxiong,JIANG Quanfu,ZOU Meifeng,WANG Songpei,LI Xiaomin,WU Chunying
ADAM (2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine) is suggested as a promising serotonin transporter (SERT) imaging agent for central nervous system. In this paper, biodistribution studies in rats showed that the initial uptake of 131I-ADAM in the brain was high (1.087%ID at 2 min post-injection), and consistently displayed the highest binding (between 60~240 min post-injection) in hypothalamus, a region known with the highest density of SERT. The specific binding((T/CB)-1) of 131I-ADAM in hypothalamus were 2.94, 3.03 and 3.09 at 60, 120 and 240 min post-injection, respectively. The (T/CB)-1 was significantly blocked by pretreatment with paroxetine, which is known as a serotonin site reuptake inhibitor, while another nonselective competing drug (5HT2A antagonist) Ketanserin, showed no block effect. The rat brain autoradiography and analysis showed that there was a high 131I-ADAM uptake in hypothalamus, the ratio of hypothalamus/cerebellum was significantly reduced from 7.94±0.39 to 1.30±0.56 by pretreatment with paroxetine at 60 min post-injection. Blood clearance kinetics was performed in rats, and the initial half-life of 13.79 min and late half-life of 357.14 min were obtained. The kinetic equation is: C=3.6147e-0.0725t + 1.0413e-0.0028t. The thyroid uptake was 0.009% ID and 1.421% ID at 2 min and 120 min post-injection, respectively, suggesting that in vivo deiodination may be the major route of metabolism. Toxicity trial showed that the dose per kilogram administered to mice was 1000 times greater than that to humans, assuming a weight of 50kg. These data suggest that 131I-ADAM may be useful for SPECT imaging of SERT binding sites in the brain.
keywordDepression;SERT;ADAM;Imaging agent;Radionuclide imaging;Biodistribution;
Research article 20 Aug 2007
LI Xiaomin,CHEN Zhengping,WANG Songpei,TANG Jie,LIN Yansong,ZHU Zhaohui,FANG Ping
The paper is to study pharmacologic characteristics of 18F-FP-β-CIT (18F-N-(3-fluoropropyl)-2β- carbomethoxy-3β- (4-iodophenyl)nortropane) as an imaging agent for dopamine transporter. The radiochemical purity of 18F-FP-β-CIT in aqueous solution was over 95% after standing at room temperature for 4h. Biodistribution displayed rapid uptake in rat brain (1.375 %ID/organ at 5min and 0.100 %ID/organ at 180 min) and the striatal uptake was 1.444, 0.731, 0.397, 0.230 and 0.146 %ID/g at 5, 30, 60, 120 and 180 min, respectively. The values of striatum/cerebellum, striatum /frontal cortex and striatum / hippocampus in rat's brain at 30 min were 3.38, 2.17 and 2.40 respectively. The uptake in striatum can be blocked by β-CFT, suggesting that 18F-FP-β-CIT binds to DAT peculiarly. The compound was rapidly cleared from monkey's blood. The striatal uptake was bilaterally decreased in the left-sided lesioned PD rats, compared with normal control. Brain PET imaging studies in normal monkey showed that 18F-FP-β-CIT was concentrated in striatum. The test of undue toxicity showed that the dose received by mice was 1250 times as by human, which indicates that 18F-FP-β-CIT is very safe. So 18F-FP-β-CIT is a promising PET imaging agent for DAT with safety and validity.
keywordParkinson';s disease;Dopamine transporter;Radionuclide imaging;18F-FP-β-CIT;Biodistribution;Pharmacokinetics;
Research article 20 Aug 2007
CHEN Yangchun,CHEN Shaoliang,JU Dianwen,SHI Hongcheng,YAO Zhifeng
The purpose of this study was to assess the absorbed dose of tumor and main critical organs in 131I labeled chimeric tumor necrotic treatment (chTNT). In 9 patients, a single intravenous dose of (29.6±3.7) MBq/kg was administered. Blood samples were drawn at different time intervals, and urine was collected for up to one week. Tissue distribution of 131I –chTNT was followed for up to one week by gamma camera imaging. Absorbed doses to the whole body and to normal organs were computed according to the MIRD scheme using Mirdose-3 software. S-factors for lung tumors were estimated by comparison with lungs of similar mass and position in the body. It was found that mean serum disappearance half time values for 131I-chTNT were (4.93±9.36) h and (61.7±21.2) h for α, β respectively, while that for whole body was(99±10) h. Mean urine biological clearance half time value was (90±10) h. The absorbed dose to tumor was (8.28±2.65) Gy, and the tumor-to-nontumor dose ratio was 3.95±1.55. And the mean effective dose to patients was (1.02±0.29) mSv/MBq.
keywordRadioimmunotherapy;Radiation dosage;Iodine radioisotopes;
Research article 20 Aug 2007
LIU Congjin,LIU Xingdang,ZHANG Guangming,LI Ding,WANG Jian,YANG Liqin,JIANG Yuping
Dopamine transporter (DAT) mediates the regulation of dopaminergic function. Two agents of TRODAT-1 and FP-CIT were observed in evaluating DAT change of Parkinson's disease (PD). The relationship between them was also evaluated. The results suggested that 99mTc-TRODAT-1 SPECT and 131I-FP-CIT SPECT may serve as sensitive and objective in vivo markers to reflect the severity of PD. The 99mTc-TRODAT-1 image is more accurate and clearer compared with 131I-FP-CIT.
keyword99mTc-TRODAT-1 SPECT;131I-FP-CIT SPECT;Parkinson';s disease;
ADVANCED NUCLEAR INSTRUMENTATION AND DETECTION
Research article 20 Aug 2007
D. Rezaei-Ochbelagh,H.Miri HAKIMABAD,R.Izadi NAJAFABADI
Experiments were carried out to investigate the possible use of neutron backscattering for the detection of polyethylene (PE) sample buried in the soil. In detection of landmine by neutrons, the neutron detector and its shield play an important role. In this paper, the effects of graphite, heavy water, polyethylene and boric acid moderators on the flux of back scattered neutrons were investigated. We have also experimentally verified the effect of BF3 detector shield and obtained good agreement with theory.
keywordLandmine;Am-Be neutron source;Neutron backscattering;Moderator;Heavy water;BF3 detector;
MISCELLANEOUS
Research article 20 Aug 2007
LIN Qian,CAO Xuewu
Fuel Coolant Interactions (FCIs) are important issues in nuclear reactor severe accident analysis. In FCIs, fragmentation model of molten droplets is a key factor to estimate degree of possible damage. In this paper, the mixing process in FCIs is studied by the simulation of MIXA experiment with hydrodynamic fragmentation model. The result shows that hydrodynamic fragmentation model underestimates the fragmentation rate of high temperature molten droplets under the condition of low Weber numbers. It is concluded that models based on thermal fragmentation mechanism should be adopted to analyze the FCI process and its consequence.
keywordSevere accident;FCI;Molten fuel droplet;Fragmentation;MIXA;
Research article 20 Aug 2007
WU Geping,QIU Suizheng,SU Guanghui,JIA Dounan
A narrow annular test section of 1.5mm gap and 1800mm length was designed and manufactured, with good tightness and insulation. Experiments were carried out to investigate characteristics of flow instability of forced-convection in vertical narrow annuli. Using distilled water as work fluid, the experiments were conducted at pressures of 1.0~3.0MPa, mass flow rates of 3.0~25kg/h, heating power of 3.0~ 6.5kW and inlet fluid temperature of 20 oC, 40 oC or 60oC. It was found that flow instability occured with fixed inlet condition and heating power when mass flow rate was below a special value. Effects of inlet subcooling, system pressure and mass flow rate on the system behavior were studied and the instability region was given.
keywordFlow instability;Experimental research;Vertical narrow annuli;Forced-convection;
Research article 20 Aug 2007
LI Tianshu,YANG Yanhua,LI Xiaoyan,HU Zhihua
A series of experiments of the premixing stage of fuel-coolant interactions (FCI), namely the particles falling into water, were carried out. The force on the particles during the course of falling has been studied. The dropping character of hot particle was influenced by three main parameters, i.e., particle temperature, particle diameter and coolant subcooling that varied over a wide range. A high-speed camera recorded the falling speed of the particle and the moving curves were obtained. The experimental results showed that for the film boiling on the surface of particle and water, the temperature increase of either particle or coolant would slow down the particle falling velocity. The falling velocity of particle in small diameter is lower than that of the bigger particle. The present work can provide an experimental foundation for further investigation of high-speed transient evaporation heat transfer.
keywordVapor explosion;FCI;Observable experiment equipment;