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AN OBSERVATION OF THE γ-RAYS FROM 100 keV TO 830 keV IN ATMOSPHERE AT SEA LEVEL DURING ANNULAR ECLIPSE OF THE SUN

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Chinese Science Bulletin 1990年第5期35卷 413-414页

作者：卞祖和林翔鸿万恩三许红兵吴秋文刘作屏吴铁军唐孝威 Department of Modem Physics University of Science and Technology of China Hefei 230026 PRC

People have long begun considering the relativity of the atmospheric radioactivity with the sun activity and the atmospheric conditions.An annular eclipse of the sun took place in China on the 23rd September, 1987. On this occasion, we performed an experimental observation of the γ-rays from 100 keV to 830 keV in atmosphere at sea level at Tianchang County in Anhui Province which is located at the southern edge of the annular eclipse band, i. e. at longitude 119°01′E, latitude 30°41′N, at an altitude of 20.8 m. The exact time of the annulr eclipse of the

关键词： annular eclipse of the sun radioactivity in atmosphere.

RADIATION FIELD FROM A RECTANGULAR PLAQUE SOURCE FOR RADIATION PROCESSING

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Nuclear Science and Techniques 1993年第3期4卷 171-175页

作者：冯永样李志良李盘林许梦杰 Shanghai University of Science and Technology Shanghai 201800 China. Institute of Nuclear Research Academia Sinica Shanghai 201800 China

Evaluation of the Hubbell integral for an omnidirectional detector response to a rectangular plaque gamma emitting radiation source using a different numerical computation method on a personal computer was made. For a plaque consisting of several strip gamma emitters, exposure rates at different positions above the source were calculated using ’exact’ evaluation and an approximate method. Optimization method is used to find source activity of each strip, so as to acquire desirable dose uniformity of the irradiated products. In uses of the Hubbell integral, by introducing appropriate programming, computation time can be saved.

关键词： Numerical solution 60Co source radioactivity Hubbell integral

Assessment of Activity Concentration of Radionuclides in Sediment from Oil Producing Communities of Delta State, Nigeria

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Journal of Environmental Protection 2015年第6期6卷 640-650页

作者： Caroline Nihinlola Iwetan Ibiyinka Agboola Fuwape Adeseye Muyiwa Arogunjo Ganiyu Obor Physics Department Federal University of Technology Akure Nigeria Biochemistry Department Federal University of Technology Akure Nigeria

Activity concentrations of twenty-six (26) samples of sediment collected from rivers from eleven (11) oil-producing communities and two (2) non-oil producing communities in Delta state of Nigeria were studied. Hyper Purity Germanium (HPGe) Detector was used for counting and detection of radionuclide content of all samples. Results of the samples analysed showed that the radioactivity concentrations of K40, Th232 and U238 in the sediment samples from oil-producing areas range from 32.47 Bq·kg-1 to 525.1 Bq·kg-1 with an average of 302.15 Bq·kg-1, 6.31 Bq·kg-1 to 19.33 Bq·kg-1 with an average of 11.66 Bq·kg-1, and 4.45 Bq·kg-1 to 18.69 Bq·kg-1 with an average of 8.66 Bq·kg-1 respectively. Activity concentrations at the control site ranged from 3.15 Bq·kg-1 to 4.80 Bq·kg-1, 2.27 Bq·kg-1 to 4.18 Bq·kg-1 and 1.15 Bq·kg-1 to 1.76 Bq·kg-1 for K40, Th232 and U238. These values are within the world average;natural radioactivity mapping of the study area is carried out using the Surfer software. Statistical analysis of the results showed that there is a significant difference between the radionuclide concentrations of the sediment samples from rivers in the oil producing site compared to results from non-oil producing communities, except for one of the oil producing site samples (Idumuesah) which has values that are close to those from the control sites for K40. The values of the radiological assessment indices obtained were observed to be within the permissible maximum values;hence the radiation hazard at study areas are negligible. However, concentration values of studied radionuclide at the oil-producing study areas were observed to be higher than values from the non-oil producing sites in most cases. It could therefore be reported that the operations of the oil companies in Delta state of Nigeria may have contributed to the high radioactivity level of the river sediments. Although the concentration at the time of this study poses no risk, further industrial activities in the study area may raise the activity concentrati

关键词： Sediment Natural radioactivity TENORM HPGe Detector

Increases in Mortality for All Causes and All Cancers Combined before and after Startup of a Nuclear Power Plant in New Jersey, USA

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Journal of Environmental Protection 2019年第4期10卷 488-499页

作者： Joseph Mangano Janette Sherman Radiation and Public Health Project New York NY USA

The Salem/Hope Creek nuclear plant in southern New Jersey is one of just four U.S. plants with three large reactors (all others consist of one or two). These reactors started operations in 1976, 1980, and 1986 and routinely released toxic radioactive gases and particles into the environment. Only a single study has been performed by federal officials on cancer near nuclear plants—a study now 30 years old. A review of official mortality data using four-year periods shows the Salem County cancer death rate was consistently just below that of other New Jersey counties up to the mid-1980s. However, from 1983-1986 to 2015-2017, the county rate soared from -5.4% below the rest of the state to +32.6% above. The county/state mortality ratio for all causes also increased rapidly in these periods, from +0.6% above to +28.4% above the state. Salem now has the highest cancer death rate, and the 2nd highest total death rate of any New Jersey county. Had the 1983-1986 county-state ratios not changed in the following 31 years, 3493 fewer deaths (1018 of them from cancer) would have occurred among Salem County residents. The lack of any apparent etiologies that could have caused such a dramatic and unexpected change, plus the fact that the Salem/Hope Creek reactors are aging, corroding, and more prone to leaking radionuclides, emphasizes the immediate need for more studies of this type, and the inclusion of local health as a crucial factor in public decisions on the plant’s future.

关键词： Radiation Nuclear Power Nuclear Reactors radioactivity Cancer

Quality Characteristics and Radioactive Contamination of Wood Pellet Imported in Italy

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Open Journal of Applied Sciences 2015年第5期5卷 183-190页

作者： Massimo Calabrese Matteo Quarantotto Chiara Cantaluppi Andrea Fasson Paolo Bogoni Department of Economics Business Mathematics and Statistics University of Trieste Trieste Italy University of Trieste Trieste Italy Institute for Energetics and Interphases National Research Council of Italy Padova Italy

The problem of Caesium-137 (137 Cs) contamination of the imported wood pellet used for burning has been reported in Italy since June 2009. Since then, sampling and analysis were performed at the crossing border points of the provinces of Trieste and Gorizia, on request of the Health and Customs Border Bureau. This paper presents the results of the analysis performed on 65 samples from August 2010 to March 2012, which covered a total of products over 1500 tons of various origins, imported from Eastern Europe and the Balkans. Most of the samples showed very low 137 Cs activity concentrations;only a few hot spots showed 137 Cs activity concentrations higher than 100 Bq·kg-1. The results of dose evaluations for wood pellet stoves users under the hypotheses assumed in this study were largely below the threshold of radiological relevance.

关键词： radioactivity Wood Pellet Biofuels Caesium-137 Radioprotection

Measurement of Radon Exhalation Rate in Some Building Materials Using Nuclear Track Detectors

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World Journal of Nuclear Science and Technology 2015年第3期5卷 141-148页

作者： Hesham A. Yousef A. H. El-Farrash A. Abu Ela Q. Merza Physics Department Faculty of Science Suez University Suez Egypt Physics Department Faculty of Science Mansoura University Mansoura Egypt

In this paper, forty samples of building materials collected from local market in Dakahlia Governorate, Egypt. The radon concentration in these samples were measured using solid state nuclear track detector. Solid state nuclear track detectors have become an important tool in every investigation of the radon levels in the surrounding environment. The obtained results have shown that the highest average of radon concentration in granite samples and the average value is 845.43 Bqm-3, while the lowest average value is white cement 68.42 Bqm-3. The present work is important to detect any harmful radiation in our houses that affect human and to establish a data base for building materials which, used in a local market. The obtained results show that the radon concentrations of the most samples are below the allowed limit of ICRP.

关键词： Radon radioactivity Building Materials Radiation LR-115

Method to Measure Indoor Radon Concentration in an Open Volume with Geiger-Mueller Counters: Analysis from First Principles

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World Journal of Nuclear Science and Technology 2016年第4期6卷 232-260页

作者： M. P. Silverman Department of Physics Trinity College Hartford CT USA

A simple method employing a pair of pancake-style Geiger-Mueller (GM) counters for quantitative measurement of radon activity concentration (activity per unit volume) is described and demonstrated. The use of two GM counters, together with the basic theory derived in this paper, permit the detection of alpha particles from decay of and progeny ( 218Po, 214Po) and the conversion of the alpha count rate into a radon concentration. A unique feature of this method, in comparison with standard methodologies to measure radon concentration, is the absence of a fixed control volume. Advantages afforded by the reported GM method include: 1) it provides a direct in-situ value of radon level, thereby eliminating the need to send samples to an external testing laboratory;2) it can be applied to monitoring radon levels exhibiting wide short-term variability;3) it can yield short-term measurements of comparable accuracy and equivalent or higher precision than a commercial radon monitor sampling by passive diffusion;4) it yields long-term measurements statistically equivalent to commercial radon monitors;5) it uses the most commonly employed, overall least expensive, and most easily operated type of nuclear instrumentation. As such, the method is par-ticularly suitable for use by researchers, public health personnel, and home dwellers who prefer to monitor indoor radon levels themselves. The results of a consecutive 30-day sequence of 24 hour mean radon measurements by the proposed GM method and a commercial state-of-the-art radon monitor certified for radon testing are compared.

关键词： radioactivity Radon Concentration Geiger-Mueller Counter Alpha Particle Diffusion Alpha Range

Theoretical Determination and Experimental Verification of Transport Index of Rectangular Shaped Radioactive Containers

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World Journal of Nuclear Science and Technology 2014年第2期4卷 73-80页

作者： Khalid Jamil Muhammad Asim Majid Irfat Shahid Manzoor Department of Physics and Applied Mathematics Pakistan Institute of Engineering and Applied Sciences Islamabad Pakistan Radiation Physics Laboratory Physics Department COMSATS Institute of Information Technology Islamabad Pakistan

Ionizing radiations are widely used to sustain and enhance our quality of life in the areas such as medical diagnosis, therapy, scientific research and industry etc. Ionizing radiations are available from radioactive sources which are made of radioactive materials. The radioactive materials are produced in either nuclear power or research reactors or nuclear accelerators or extracted from the naturally found radioactive ores. These radioactive sources and radioactive materials need to be transported from their places of production to the places of applications and finally to waste repositories. The radioactive materials are transported in well designed packages having various shapes and sizes. In the field of radioactive transport, it is a mandatory to find the Transport Index (TI) to be mentioned on each package for transportation. This research is focused on the determination of the maximum γ-ray radiation dose at one meter from the surface of cubic and rectangular shaped package or containers. A computer code “Solid Angle for Transport Index” (SAFTI) has been developed using MATLAB to determine the location of maximum value of the radiation dose rate from the surface of a rectangular or square container. This maximum dose rate is used to determine the transport index. Some of the results of the code have been compared with the experimental results. The results of this research are useful not only to determine TI for individual packages but also to find the TI of the vehicles carrying the transport packages.

关键词： Ionization Radiations radioactivity Industry Therapy Nuclear Waste Transport Index

Investigation of Heavy Metals and Radionuclide’s Impact on Environment Due to The Waste Products of Different Iron Processing Industries in Chittagong, Bangladesh

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Journal of Environmental Protection 2017年第9期8卷 974-989页

作者： Mohammad Saifur Rahman Bijoy Sonker Barua Md. Rezaul Karim Masud Kamal Department of Chemistry Chittagong University of Engineering and Technology Chittagong Bangladesh Department of Civil Engineering Southern University Bangladesh Chittagong Bangladesh Bangladesh Atomic Energy Commission Dhaka Bangladesh

The waste products, such as induction furnace slag, ladle furnace slag, air pollution control dust, and ramming mass collected from major iron processing industries in Chittagong, Bangladesh were analyzed for heavy metals and naturally radioactive elements. The concentrations of heavy metals Fe, Cr, Mn, Co, Cd, Ni, Pb, Cu and Zn were obtained from atomic absorption spectrophotometer (AAS) analysis with flame atomizer and the radioactivities due to 226Ra, 232Th and 40K were determined using high purity germanium (HPGe) detector of well shielded gamma-ray counting system. From the mean specific activities of the above three natural radionuclides in the investigated samples, the radium equivalent activity (Raeq) and the external hazard index (Hex) were calculated. The study showed the prospect of contamination of environmental materials (viz., soil, water, air, plant) due to many of these investigated elements by using the collected waste products in landfill. The chemical process of ion exchange indicates that the elevated heavy metals in soil can play a role to increase the natural radioactivity of the soil. The obtained Raeq as well as Hex indicated the insignificant radiation hazard due to the activities of primordial radionuclides found in the investigated samples.

关键词： Heavy Metals Natural radioactivity Slag Air Pollution Control Dust Ramming Mass Iron Processing Industries