Integrated nuclear techniques for sedimentation assessment in Latin American region

The paper shows the novel techniques introduction in the region of Latin America and the Caribbean in order to strengthen the surveillance and monitoring of the sedimentation phenomenon in the surface water reservoirs.The integrated use of the nuclear techniques allows a more complete assessment of water and land sustainability.With the development of a regional project,supported by the International Agency of Atomic Energy,Cuba participates as technical leader for 15 countries,to encourage and implement the integrated application of 3 nuclear techniques(Fallout Radionuclides(137Cs,7Be,210pb),Compound Specific Stable Isotopes(fatty acids of the(e)13C)and the Isotopic Hydrology(18O,2H,3H).The methodology used in the last studies referred to RLA 5076 Project is to apply the integration of these three techniques allows evaluating,in the hydraulic facilities and surface water reservoirs,the negative sedimentation impacts in natural and anthropic process as environmental and social risk.These techniques evaluate the sedimentation process and its synergy,obtaining since the soil quantification in the landscape,definition the soil origin deposited until the dynamic characterization of the water body as soil receptor.The integrated application of these nuclear techniques in the Project RLA-5076 confirms it as a useful tool to support the decisions makers in the definition of the national strategies and programs related to the land and the water resources sustainability.With the support of the IAEA projects in the Latin American and Caribbean region,has been evidenced an important increment in the use of these novel techniques.

Nuclear Science and Techniques收录情况简介

自2006年起,Nuclear Science and Techniques(《核技术》(英文版))加入ScienceDirect数据库。ScienceDirect(www.sciencedirect.com)是全球最著名的科技医学全文数据库之一,

NUCLEAR SCIENCE AND TECHNIQUES A comprehensive table of contents of Vol.14, 2003

SYNCHROTRON TECHNOLOGY AND APPLICATIONSNo.1 1 Intermediate energy light sources and the SSRF project ZHAO Zhen—Tang9 Multiple scattering approach to X-ray absorption spectroscopyM.BENFATTO,Zi—Yu WU20 Electron gun for SSRFSHENG Shu—Gang,LIN Guo—Qiang,GU Qiang,LI De—Ming24 A new digital beam position monitor in SSRFCHENG Wei—Xing,LIU

Preliminary Research Results for the Generation and Diagnostics of High Power Ion Beams on FLASH II Accelerator

The preliminary experimental results of the generation and diagnostics of high power ion beams on FLASH II accelerator are reported. The high-power ion beams presently are being produced in a pinched diode. The method for enhancing the ratio of ion to electron current is to increase the electron residing time by pinching the electron flow. Furthermore, electron beam pinching can be combined with electron reflexing to achieve ion beams with even higher efficiency and intensity. The anode plasma is generated by anode foil bombarded with electron and anode foil surface flashover. In recent experiments on FLASH II accelerator, ion beams have been produced with a current of 160 kA and an.energy of 500 keV corresponding to an ion beam peak power of about 80 GW. The ion number and current of high power ion beams were determined by monitoring delayed radioactivity from nuclear reactions induced in a 12C target by the proton beams. The prompt 7-rays and diode bremsstrahlung X-rays were measured with a PIN semi-conductor detector and a plastic scintillator detector. The current density distribution of ion beam were measured with a biased ion collector array. The ion beams were also recorded with a CR-39 detector.

Density Assessment of Different Metals and Alloys by Gamma-Ray Transmission Technique via Using Co-60 Radioactive Source

In this study, density measurements were observed by using gamma transmission technique. Co-60 gamma emitter was used as gamma radioisotope source. Regarding the gamma-ray transmission method, initial radiation intensity （I0） and radiation intensity （I） determined experimentally and [I/I0] rates were calculated and then density of materials could be determined by using Beer-Lambert Equation. Experimental application performed on widespread industrial metals or metal alloys e.g. lead, copper and steel, brass. With this study, it is shown that gamma transmission technique can be used for density measurements.

Nuclear Technique and Agriculture in China

Nuclear technique is a powerful scientific tool in agricultural research, an area with fruitful achievements in China. Application of nuclear technique in agriculture (Nuclear Agricultural Sciences) based on the development of related science and technology is a high-tech area, and also a significant aspect of non-electrical power application of nuclear technique. As an important component of agricultural science and technology, Nuclear technique application in agricultural field has achieved a lot and made remarkable contributions to the economic, social and ecological development of China. The current paper reviews the achievements, and presents the situation of the application of nuclear technique in the Chinese a-griculture briefly. The author strongly suggests that Chinese government should pay more attention to the study on the application of nuclear technique in agriculture, in order to promote its development and contribute more to the Chinese society and agriculture.

Assessment of deforestation impact on soil erosion in loess formation using 137Cs method (case study: Golestan Province, Iran)

Golestan,a province in the North-East of Iran,is characterized by high coverage of loess deposits.Since 1963,the area has experienced approximately 200,000 ha deforestation due to land-use changes in agriculture and increasing demand for wood.Approximately,110,000 ha of the clear-cut lands are under dry-farming,mainly for wheat cropping,and about 86,000 ha have been reforested.This IAEA funded project is the first attempt to use nuclear techniques in the East of Hircanian Forest for determination of on-site impacts of deforestation due to two land-use changes(i.e.dry farming and reforestation).Practicing long-term dry-farming led to 60%soil losses with a mean rate of 2 mm per year.The net erosion rate of croplands on loess deposits in the study area was 32.27 t ha-1 yr-1.Reforestation,cultivation of even-aged Cypress trees since 1993,showed 13 to 60 percent effectiveness in soil conservation.Dry-farming land use resulted in the loss of 95 t ha-1 soil organic carbon(SOC)stock at a mean rate of 1.7 t ha-1 over 54 years.Cultivating Cypress trees successfully restored the SOC content by 100%compared with the SOC in original forests.The conversion of dry-farming lands to orchards of olive trees since 2004,brought more income for farmers but were less effective in soil conservation because of low canopy cover of olive trees.Our data provide key information and guidance for land users and decisionmakers about implementing strategic and sustainable conservation practices to restore degraded land.