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This paper presents the thermoluminescence properties of K2GdF5:Tb material irradiated in a reference neutron-gamma field and its possibility to be used in neutron dosimetry. Double fluoride of K2GdF5 doped with 10 at% Tb3+ ions was synthesized under solid-state reaction conditions and irradiated in the reference neutron-gamma field of 241Am-Be source. The thermoluminescence glow curves were measured by the Rexon UL-320 TLD reader connected with the WinRex-320 processing program for obtaining the integrated thermoluminescence signals (counts). The results show that the temperature peaks of the irradiated K2GdF5:Tb material concerning the gamma and neutron fields at the distance of 100 cm from the source are at 230°C and 300°C, respectively. The sensitivity ratios of fast-to-thermal neutron and gamma-to-thermal neutron are 6.3 % and 18.2 %, respectively. The batch homogeneity and reproducibility are less than 30 % and 7.5 %, respectively. The linearity is less than 10 % in the dose range of less than 24 mSv. The detection threshold is less than 0.1 mSv, and the fading is 10.7 % after 90 days of irradiation. These thermoluminescence properties of K2GdF5:Tb material considerably satisfy the requirements to be used in neutron dosimetry.

Assessment of the characteristics of natural radionuclides and 137Cs in soil in Phonsavan district, Xiengkhouang province, Laos has been conducted using a standard electrode coaxial Ge (SEGe) detector. Soil samples were collected at 20 locations close to the populated and agricultural area in Phonsavan district. The average activity concentrations of 226Ra, 238U, 232Th, 40K and 137Cs are 54.0 ± 2.5, 65.1 ± 4.4, 96.9 ± 3.7, 433.2 ± 20.7, and 1.54 ± 0.13 Bqkg-1, respectively. The average radium equivalent activity Raeq is 225.9 ± 7.8 Bqkg-1. The highest Raeq of 269.9 Bqkg-1 is still lower than the safety limit of 370 Bqkg-1. Associated radiological hazard indices, such as absorbed gamma dose rate, outdoor annual effective dose equivalent, excess lifetime cancer risk, external and internal hazard indices, and gamma index, were also calculated and presented.

Purpose: Innovation is considered as a core element of sustainable competitive advantage in the rapidly changing environment. However, in Vietnam, researches on innovation are very rare, which are mostly general reports without underlying analyses of innovation in firms, especially determinants for innovation. Therefore, this paper focuses on analyzing critical successful factors for innovation in Vietnamese firms. Design/methodology/approach: This study used primary data through questionnaire survey from November 2015 to February 2016. Respondents were senior managers of firms located mostly at Hanoi (Northern), Hochiminh (Southern) and Danang city (Central). The questionnaire included multi-items designed to measure factors. Each item was measured by 5 point Likert scale: 1 (strongly disagree) to 5 (strongly agree). Questionnaires were administerd to 500 firms belonging to list of Vietnam Chamber of Commerce and Industry (VCCI) in these three cities with rate of 40% (Hochiminh city), 40% (Hanoi city) and Danang (20%). However, there were 360 returned questionnaires and valid to next analyses. Analysis methodologies of reliability, factor analysis and regression are utilized in this paper. Findings: We developed and tested a model of determinants for Innovation in Vietnamese firms. The major contribution of this study is testing six determinants for innovation in Vietnamese companies. The results showed that awareness of innovation, innovation strategy and policy, organization for innovation, HR for innovation and building capabilities have positive impact on innovation. Originality/value: This study makes a contribution for both academics and practitioners. For academics, this study provided one more empirical evidence of the determinants for innovation. Regarding practical implications, this study suggests that Vietnamese companies have to strengthen capabilities for employees through training, encourage generation of new ideas, rule breaking, and innovative behaviors by organizational members. Together, having high awareness of innovation, building rational innovation strategy and policy is essential factors that firms should possess and develop to enhance innovation performance. Although there is no confirmation for impact of finance on innovation level, firms should understand that increasing innovation investment can bring favorable condition to create innovation especially in SMEs.