Environmental Radionuclides in Surface Soils of Vietnam

A database on 238U, 232Th, 40K, and 137Cs in surface soils was established to provide inputs for the assessment of the collective dose to the population of Vietnam and to support soil erosion studies using 137Cs as a tracer. A total of 292 soil samples was taken from undisturbed sites across the territory and the concentrations of radionuclides were determined by gamma spectrometry method. The multiple regression of 137Cs inventories against characteristics of sampling locations allowed us to establish the distribution of 137Cs deposition density and its relationship with latitude and annual rainfall. The 137Cs deposition density increases northward and varies from 178 Bq m–2 to 1,920 Bq m–2. High rainfall areas in the northern and central parts of the country have received considerable 137Cs inputs exceeding 600 Bq m–2, which is the maximum value that can be expected for Vietnam from the UNSCEAR global pattern. The mean activity concentrations of naturally occurring radionuclides 238U, 232Th, and 40K are 45, 59, and 401 Bq kg–1, respectively, which entail an average absorbed dose rate in air of 62 nGy h–1, which is about 7% higher than the world average

The role of rainfalls for erosion and sedimentation in the degraded mangroves, Can Gio district, Vietnam

Joint Research on Environmental Science and Technology for the Eart

FAMEBASE VER. 2.0 – Hệ quản trị cơ sở dữ liệu cho người sử dụng đầu cuối

FAMEBASE VER. 2.0 – Hệ quản trị cơ sở dữ liệu cho người sử dụng đầu cuối

Héritages du musical dans la pop culture contemporaine

International audienc

Greenhouse Gas Emission from Freight Transport-Accounting for the Rice Supply Chain in Vietnam

AbstractThe freight transport related greenhouse gas emission has been increasing quickly in Vietnam. Vietnamese government is aiming for CO2 reduction, which focuses on accurate definition of the contribution of different industry sectors to greenhouse gas emission. The objective of this paper is a summary of studies on transport emission factors in Vietnam and other countries in the world. As a consequence, the conclusion on emission factors currently used in Vietnam is generated. The study takes the rice industry in Vietnam as an example sector for the detailed examination of total emission. The preliminary results show that nearly 100 tons of CO2 were emitted from freight movement in the rice industry in 2011, approximately 0.8% of total CO2 emission borne by freight transport sector of Vietnam. Besides, modal shift from the road to inland waterway transport in the rice supply chain can bring benefits for not only the rice industry but also environmental protection

My Sister Eileen : classique et atypique

International audienc

Mettre en scène. Théâtre et cinéma

International audienc

\uc9valuation et protection parasismiques des b\ue2timents

Whether or not a building can survive an earthquake depends primarily on its behaviour when horizontally shaken. This behaviour can be predicted and remedial measures, if necessary, invoked. To determine whether a building needs such remedial measures, building owners and professionals would first subject it to a seismic screening process. The screening process determines which buildings should be slated for a detailed evaluation. This usually includes those buildings where the potential for loss of life can be high. Once they have been screened and evaluated, buildings can be retrofitted for seismic resistance using various measures.La r\ue9sistance d'un b\ue2timent \ue0 un tremblement de terre d\ue9pend principalement de son comportement face \ue0 des secousses horizontales. Ce comportement est pr\ue9visible et des mesures pour y rem\ue9dier peuvent \ueatre prises. Pour d\ue9terminer s'il faut prendre de telles mesure pour tel ou tel b\ue2timent, les propri\ue9taires de b\ue2timents et les sp\ue9cialistes soumettront en premier le b\ue2timent \ue0 une s\ue9lection sismique. Ce processus permet de d\ue9terminer quels sont les b\ue2timents qui doivent subir une \ue9valuation plus compl\ue8te. Parmi ceux-l\ue0 sont g\ue9n\ue9ralement compris les b\ue2timents o\uf9 le risque de pertes humaines peut \ueatre \ue9lev\ue9. D\ue8s que les b\ue2timents ont \ue9t\ue9 s\ue9lectionn\ue9s et \ue9valu\ue9s, ils peuvent alors \ueatre prot\ue9g\ue9s de diff\ue9rentes mani\ue8res contre les s\ue9ismes.Also available in English: Seismic evaluation and upgrading of buildingsPeer reviewed: NoNRC publication: Ye

Economic and nutrient discharge tradeoffs of excreta-fed aquaculture in the Mekong Delta, Vietnam

The present study quantifies the effects on production, nutrient discharge and economic return of the use of pig and human excreta in pond tanning. On-farm data from various studies were integrated and analyzed applying single and multiple regression methods. Pond-dissolved oxygen concentration, water exchange and nutrient discharge interacted and were strongly affected by input level. Increased input levels coincided with farmers exchanging more water and discharging more chemical oxygen demand (COD), nitrogen (N), phosphorus (P) and total suspended solids (TSS). Fish yield and the accumulation of organic carbon, N and P in pond sediments increased with the excreta input level. Using a regression model, it was predicted that with an excreta input of 5 kg N ha(-1) day(-1), a fish yield of 8380 kg and an economic return of 52 million VND ha(-1) year(-1) can be obtained while about 2060 kg COD, 645 kg N, 210 kg P and 39,200 kg TSS ha(-1) year(-1) will be discharged. At this input level, it was estimated that about 9% of input-N will be recovered in harvested fish while 52% will accumulate in the pond sediment. Hence, fish culture reduces nutrient discharge from excreta by 61% while generating income for resource-poor farmers. However, in the long run such a system will become unsustainable when more farmers take up this farming practice. The challenges are to reduce nutrient discharges from ponds while maintaining high production and profitability and to use the nutrients accumulated pond sediments more efficiently. (c) 2007 Elsevier B.V. All rights reserved