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Estimation of the radionuclide distribution in sediment in coast area

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Journal of Environmental Sciences 2001年第4期13卷 398-400页

作者： SHEN Zhen-yao YANG Zhi-feng LI Wei-juan NI Shi-wei YAO Lang-gen CAI Yuan Institute of Environmental Science Beijing Normal UniversityState Key Joint Laboratory of Environmental Simulation and Pollution ControlBeijing 100875China China Institute for Radiation Protection Key Laboratory of Nuclear Radiation Environmental SimulationTaiyuan 030006China

The study of the radionuelide distribution in sediment is a very important aspect in environmental impact of the low level radioactive liquid waste (LLW) from coastal nuclear facilities or nuclear power plant. Even now we do not know much about it. In this paper, a simple and useful method is put forward and it is used to estimate the nuclide distribution in sediment. The result showed that the LLW from nuclear facility or nuclear power plant will do a little harm to the sediment nearby. But the harm is not very serious. Much works have to be done before full understanding of the situation.

关键词： radionuclide coast area deposit characteristic sediment

Dating sediments on several lakes inferred from radionuclide profiles

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Journal of Environmental Sciences 1998年第1期10卷 58-65页

作者： Xiang Liang Lake Sediment and Environment Laboratory,Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences,Nanjing 210008,China

In this paper, several sediment cores from three lakes (Gucheng Lake, Dianchi Lake and Dabusopao Lake) in the different regions of China were dated radiometrically by 210 Pb, 137 Cs and in Dianchi also by 241 Am. The study shows that the profiles of 137 Cs in lake sediment of China generally have 2—4 distinct chronological markers, i.e. the onset of fallout in 1954 and peak fallout in 1963, 1974 and 1986. As many places of the northern hemisphere, the peak fallout in 1963 was the result of the atmospheric atomic weapons test. But in some areas of China, there may be have one or two other peaks of 137 Cs fallout, one can derive from Chernobyl fallout in 1986 and the other is caused by the nuclear testing fallout in early 1970s. So in these areas, the profiles of 137 Cs can have 2 or 3 peaks as the time markers. 241 Am, which is another fallout product from nuclear weapons testing, also provides a useful dating marker in Dianchi. These time markers are of considerable value to confirm 210 Pb dates in the three lakes. Despite there are some questions remain concerning the interpretation of these radionuclide records in lake sediments, coupling with 210 Pb and 137 Cs (and/or 241 Am) is suggested to be a valuable limnological tool for establishing sediment chronologies for the lake sediments in China.

关键词： lake sediment radionuclide dating method.

Effects of Food Diet Preparation Techniques on radionuclide Intake and Its Implications for Individual Ingestion Effective Dose in Abeokuta, Southwestern Nigeria

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World Journal of Nuclear Science and Technology 2012年第3期2卷 106-113页

作者： Nnamdi Norbert Jibiri Tolulope Hadrat Abiodun Radiation and Health Physics Research Laboratory Department of Physics University of Ibadan Ibadan Nigeria

The radioactivity measurements in food crops and their diet derivatives and farm soil samples from Abeokuta, one of the elevated background radiation areas in Nigeria have been carried out in order to determine the concentration levels of natural radionuclides (40K, 226Ra and 232Th). The activity concentrations of the natural radionuclides in the samples were determined via gamma-ray spectrometry using a 76 mm × 76 mm NaI(Tl) detector. Different common food crops representing the major sources of dietary requirements to the local population were collected for the measurements. The collected food crops were prepared into their different derivable composite diets using preparation techniques locale to the population. Using available food consumption data and the activity concentrations of the radionuclides, the ingestion effective doses were evaluated for the food crops and diet types per preparation techniques. For the tuberous food crop samples, the annual ingestion effective doses in the raw and different composite diets were 0.02 - 0.04 μSv and cumulatively 0.04 - 0.05 μSv while in the non-tuberous crops the doses were 0.44 - 0.70 μSv and cumulatively greater than 1 μSv respectively. Results of the study indicate that method of diet preparation is seen to play a major role in population ingestion dose reduction especially for tuberous crops than in non-tuberous crops. The study also showed that more ingestion dose could be incurred in diets prepared by roasting techniques. The result of the study will serve as a useful radiometric data for future epidemiological studies in the area and for food safety regulations and policy implementations in the country.

关键词： Natural radionuclides radionuclide Intake Gamma Ray Spectroscopy Food Crops Radiation Effective Ingestion Dose Diet Preparation Techniques

Imaging assessment of photosensitizer emission induced by radionuclide-derived Cherenkov radiation using charge-coupled device optical imaging and long-pass filters

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World Journal of Radiology 2023年第11期15卷 315-323页

作者： Winn Aung Atsushi B Tsuji Kazuaki Rikiyama Fumihiko Nishikido Satoshi Obara Tatsuya Higashi Department of Molecular Imaging and Theranostics Institute for Quantum Medical ScienceNational Institutes for Quantum Science and TechnologyChiba 263-8555Japan Department of Advanced Nuclear Medicine Sciences Institute for Quantum Medical ScienceNational Institutes for Quantum Science and TechnologyChiba 263-8555Japan

BACKGROUND radionuclides produce Cherenkov radiation(CR),which can potentially activate photosensitizers(PSs)in *** groups have studied Cherenkov energy transfer to PSs using optical imaging;however,cost-effectively identifying whether PSs are excited by radionuclide-derived CR and detecting fluorescence emission from excited PSs remain a *** laboratories face the need for expensive dedicated *** To cost-effectively confirm whether PSs are excited by radionuclide-derived CR and distinguish fluorescence emission from excited *** The absorbance and fluorescence spectra of PSs were measured using a microplate reader and fluorescence spectrometer to examine the photo-physical properties of *** mitigate the need for expensive dedicated equipment and achieve the aim of the study,we developed a method that utilizes a chargecoupled device optical imaging system and appropriate long-pass filters of different wavelengths(manual sequential application of long-pass filters of 515,580,645,700,750,and 800 nm).Tetrakis(4-carboxyphenyl)porphyrin(TCPP)was utilized as a model *** doses of copper-64(^(64)CuCl_(2))(4,2,and 1 mCi)were used as CR-producing *** and data acquisition were performed 0.5 h after sample *** image analysis was conducted by using ImageJ software(National Institutes of Health)to visually evaluate TCPP *** The maximum absorbance of TCPP was at 390-430 nm,and the emission peak was at 670 *** CR and CRinduced TCPP emissions were observed using the optical imaging system and the high-transmittance long-pass filters described *** emission spectra of TCPP with a peak in the 645-700 nm window were obtained by calculation and subtraction based on the serial signal intensity(total flux)difference between^(64)CuCl_(2)+TCPP and^(64)CuCl_(2).Moreover,the differential fluorescence images of TCPP were obtained by subtracting the^(64)CuCl_(2)image from the^

关键词： Tetrakis(4-carboxyphenyl)porphyrin Photosensitizer emission radionuclide Cherenkov radiation Optical imaging Long-pass filters

Role of radionuclide imaging for diagnosis of device and prosthetic valve infections

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World Journal of Cardiology 2016年第9期8卷 534-546页

作者： Jean-Fran?ois Sarrazin Francois Philippon Mikael Trottier Michel Tessier Department of Cardiology Institut Universitaire de Cardiologie et Pneumologie de QuébecLaval University Department of Nuclear Medicine Institut Universitaire de Cardiologie et Pneumologie de QuébecLaval University

Cardiovascular implantable electronic device(CIED) infection and prosthetic valve endocarditis(PVE) remain a diagnostic *** imaging plays an important role in the diagnosis and management of patients with CIED infection or *** the past few years,cardiac radionuclide imaging has gained a key role in the diagnosis of these patients,and in assessing the need for surgery,mainly in the most difficult *** ^(18)F-fluorodeoxyglucose positron emission tomography/computed tomography(^(18)F-FDG PET/CT) and radiolabelled white blood cell single-photon emission computed tomography/computed tomography(WBC SPECT/CT) have been studied in these *** their 2015 guidelines for the management of infective endocarditis,the European Society of Cardiology incorporated cardiac nuclear imaging as part of their diagnostic algorithm for PVE,but not CIED infection since the data were judged insufficient at the *** article reviews the actual knowledge and recent studies on the use of ^(18)F-FDG PET/CT and WBC SPECT/CT in the context of CIED infection and PVE,and describes the technical aspects of cardiac radionuclide *** also discusses their accepted and potential indications for the diagnosis and management of CIED infection and PVE,the limitations of these tests,and potential areas of future research.

关键词： Device Endocarditis Fluorodeoxyglucose Imaging Infection Leukocytes Positron emission tomography/computed tomography Prosthetic valve radionuclide Scintigraphy

Right Ventricular Dysfunction in Patients with Acute STEMI, radionuclide-Based Assessment

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World Journal of Cardiovascular Diseases 2019年第12期9卷 915-929页

作者： Samir El-Hadidy Abdalla Mohammed Shaaban Alramlawy Waheed Radwan Mohamed Affify Critical Care Medicine Department Cairo Egypt Biophysics Department Faculty of Medicine Cairo University Cairo Egypt

Background: An acute myocardial infarction, particularly one that is large and transmural, can produce alterations in the topography of both the infarcted and noninfarcted regions of the ventricle. Cardiac remodeling after acute myocardial infarction (AMI) is characterized by molecular and cellular mechanisms involving both left and right ventricles. Objective: To study the right ventricular affection in patients with acute myocardial infarction of the left ventricle and treated with primary PCI. Methods: The study was done in the critical care department, Cairo University (in which 2,500 primary percutaneous coronary interventions (PCIs) are done annually). Forty patients with acute ST-elevation myocardial infarction (STEMI) were subjected to primary (PCI), we excluded all patients with RV infarction and patients with pulmonary hypertension. RV function was assessed by first pass radionuclide angiocardiography within 48 hours of admission. Results: Regarding the incidence of right ventricular dysfunction in patients with acute left ventricular STEMI who treated with 1ry PCI, there were 21 patients (52.5%) with RV EF% patients (47.5%) with RV time to peak filling rate (TPFR) > 180 msec. There was a significant relationship between right ventricular dysfunction and duration of ICU stay, impairment of LV systolic function, failure of complete resolution of ST segment elevation, failure of early peaking of cardiac enzymes, occurrence of in-hospital complications and one year mortality. Conclusion: The incidence of right ventricular dysfunction in patients with acute left ventricular STEMI is higher than expected and has a negative impact on their outcome.

关键词： STEMI RV Affection First Pass radionuclide

EVALUATION OF radionuclide BONE IMAGING FOR SKELETAL DISEASE

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Medical Bulletin of Shanghai Jiaotong University 1993年第2期16卷 37-39页

作者：林奋袁济民 Department of Orthopaedics Renji HospitalSSMU Department of Nuclear Medicine Renji HospitalSSMU

Whole body bone scan imaging of 99mTc-MDP was performed in 80 casesfrom Sept 1991 to Feb 1992. Among them 20 patients showed negtive bone imaging and56 patients showed positive bone imaging. There were false-positive bone imaging in 4 pa-tients. Bone scan imaging has been regarded as a useful method in the early diagnosis ofshelatal disease, especially in old patients with bone metastasis. But the final confirmationof malignancy should be still cautious.

关键词： radionuclide scan imaging nuclear medicine skelatal disease

Frequency domain cardiography and radionuclide ventriculography for evaluation of left ventricular function in coronary artery disease

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Journal of Medical Colleges of PLA(China) 1991年第1期6卷 93-97页

作者：赖世忠刘池李崇信 Department of Cardiology Nanfang HospitalFirst Military Medical UniversityGuangzhou 510515

Fifty-six patients with chest pain underwent selective coronaryangiography,radionuclide ventriculography (RNV) and frequency domaincardiography (FCG) to evaluate left ventricular function in coronary artery dis-ease (CAD).The sensitivity,specificity and accuracy of FCG were 87.5%,77.8%and 82.9%,respectively,which were slightly less than those of RNV (92.5%,88.9% and 90.8%,respectively).The changes of FCG scores were negatively corre-lated with changes of LVEF (r=-0.586,P<0.01),and TS (r=-0.679,P<0.01).These results indicate that FCG may be useful for the evaluation of leftventricular function in patients with CAD.

关键词： frequency domain cardiography coronary disease radionuclide ventriculography left ventricular ejection traction myocardial infarction heart function tests

Estimation of Soot and Airborne radionuclide Emission Factors from Coal-Fired Power Plants in China

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Estimation of Soot and Airborne Radionuclide Emission Factor...