An optimal test method for paint is proposed; additionally, the Field and Laboratory Emission Cell (FLEC) method used in Europe is applied as a substitute for the 20 L small chamber method. The emission factors of t...An optimal test method for paint is proposed; additionally, the Field and Laboratory Emission Cell (FLEC) method used in Europe is applied as a substitute for the 20 L small chamber method. The emission factors of total volatile organic compounds (TVOC) and formaldehyde from oil-based paint, emulsion paint, and water-dispersion paint with a coating weight of 300 g/m2, cured for 24/48 hours, were measured using the 20 L small chamber method. The emission rate of TVOC and formaldehyde from all paints began to stabilize after approximately 7 days after 24/48 hours of curing even though Korean standards stipulate that paint should be measured and analyzed after the third day of application. The emission factor of TVOC and formaldehyde from oil-based, emulsion, and water-dispersion paints were also measured using the FLEC method. There was good correlation between the 20 L small chamber method and the FLEC method for oil-based, emulsion, and water-dispersion paint emissions. With the FLEC method, using paints prepared under identical conditions, the emission rate was stable 24 hours after installation of samples because the air flow rate of FLEC is much higher than that of a 20 L small chamber, and the relative cell volume of FLEC is much smaller than that of a 20 L small chamber.展开更多
AFoCo(Asian Forest Cooperation)Project in 2011 has funded a research and development project in Malaysia for enriching a mono-species stand established in an ex-tin mine.The project covered only for a period of 12 mon...AFoCo(Asian Forest Cooperation)Project in 2011 has funded a research and development project in Malaysia for enriching a mono-species stand established in an ex-tin mine.The project covered only for a period of 12 months.A study plot of 1 ha size was established in TTAC(Tin Tailings Afforestation Centre).Twenty indigenous tropical rainforest tree species were planted and their five year-old survival count,diameter and H(top height)growths are reported in this study.Some of them are red list species of IUCN(International Union of Conservation of Nature).The survival of the 1 ha planting trial was 53%.Mortality of the tree species is mainly caused by wild boars.The tropical rainforest tree species in this planting trial had similar growth to those planted at good mineral soils.This paper also documented the tending treatments which were implemented during post-planting that have contributed to healthy growth of the mixed-species stand.The mixed-species stand is being properly tended till to-date and hence sustained growth of the stand is anticipated.展开更多
The flowability of a root canal sealer is clinically important because it improves the penetration of the sealer into the complex root canal system. The purpose of this study was to compare the flowabilities of four r...The flowability of a root canal sealer is clinically important because it improves the penetration of the sealer into the complex root canal system. The purpose of this study was to compare the flowabilities of four root canal sealers, measured using the simple press method (ISO 6876), and their viscosities, measured using a strain-controlled rheometer. A newly developed, calcium phosphate-based root canal sealer (Capseal) and three commercial root canal sealers (AH Plus, Sealapex and Pulp Canal Sealer EWT) were used in this study. The flowabilities of the four root canal sealers were measured using the simple press method (n= 5) and their viscosities were measured using a strain-controlled rheometer (n=5). The correlation between these two values was statistically analysed using Spearman's correlation test. The flow diameters and the viscosities of the root canal sealers were strongly negatively correlated (p= -0.8618). The viscosity of Pulp Canal Sealer EWT was the lowest and increased in the following order: AH Plus〈Sealapex〈Capseal (P〈0.05). All of the tested root canal sealers showed characteristic time- and temperature-dependent changes in their rheological properties. The viscosities measured using the strain-controlled rheometer were more precise than the flowabilities measured using the simple press method, suggesting that the rheometer can accurately measure the rheological properties of root canal sealers.展开更多
基金Supported by the National Research Foundation of Korea (NRF) by the Korea Government (MEST) (No. 2011-0001031)
文摘An optimal test method for paint is proposed; additionally, the Field and Laboratory Emission Cell (FLEC) method used in Europe is applied as a substitute for the 20 L small chamber method. The emission factors of total volatile organic compounds (TVOC) and formaldehyde from oil-based paint, emulsion paint, and water-dispersion paint with a coating weight of 300 g/m2, cured for 24/48 hours, were measured using the 20 L small chamber method. The emission rate of TVOC and formaldehyde from all paints began to stabilize after approximately 7 days after 24/48 hours of curing even though Korean standards stipulate that paint should be measured and analyzed after the third day of application. The emission factor of TVOC and formaldehyde from oil-based, emulsion, and water-dispersion paints were also measured using the FLEC method. There was good correlation between the 20 L small chamber method and the FLEC method for oil-based, emulsion, and water-dispersion paint emissions. With the FLEC method, using paints prepared under identical conditions, the emission rate was stable 24 hours after installation of samples because the air flow rate of FLEC is much higher than that of a 20 L small chamber, and the relative cell volume of FLEC is much smaller than that of a 20 L small chamber.
文摘AFoCo(Asian Forest Cooperation)Project in 2011 has funded a research and development project in Malaysia for enriching a mono-species stand established in an ex-tin mine.The project covered only for a period of 12 months.A study plot of 1 ha size was established in TTAC(Tin Tailings Afforestation Centre).Twenty indigenous tropical rainforest tree species were planted and their five year-old survival count,diameter and H(top height)growths are reported in this study.Some of them are red list species of IUCN(International Union of Conservation of Nature).The survival of the 1 ha planting trial was 53%.Mortality of the tree species is mainly caused by wild boars.The tropical rainforest tree species in this planting trial had similar growth to those planted at good mineral soils.This paper also documented the tending treatments which were implemented during post-planting that have contributed to healthy growth of the mixed-species stand.The mixed-species stand is being properly tended till to-date and hence sustained growth of the stand is anticipated.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (2011-0014231)supported by the National Research Foundation of Korea funded by Ministry of Education, Science and Technology (2009-0086835)+1 种基金supported by a grant from the Kyung Hee University in 2013 (KHU-20131045)supported by Grant No. 04-2009-0032 from the SNUDH Research Fund
文摘The flowability of a root canal sealer is clinically important because it improves the penetration of the sealer into the complex root canal system. The purpose of this study was to compare the flowabilities of four root canal sealers, measured using the simple press method (ISO 6876), and their viscosities, measured using a strain-controlled rheometer. A newly developed, calcium phosphate-based root canal sealer (Capseal) and three commercial root canal sealers (AH Plus, Sealapex and Pulp Canal Sealer EWT) were used in this study. The flowabilities of the four root canal sealers were measured using the simple press method (n= 5) and their viscosities were measured using a strain-controlled rheometer (n=5). The correlation between these two values was statistically analysed using Spearman's correlation test. The flow diameters and the viscosities of the root canal sealers were strongly negatively correlated (p= -0.8618). The viscosity of Pulp Canal Sealer EWT was the lowest and increased in the following order: AH Plus〈Sealapex〈Capseal (P〈0.05). All of the tested root canal sealers showed characteristic time- and temperature-dependent changes in their rheological properties. The viscosities measured using the strain-controlled rheometer were more precise than the flowabilities measured using the simple press method, suggesting that the rheometer can accurately measure the rheological properties of root canal sealers.