Pyrolysis properties of lignin separated from four different kinds of wood （fir, larch, poplar, and eucalyptus） compared with commercial lignin were investigated using a thermogravimetric analyzer coupled to a...Pyrolysis properties of lignin separated from four different kinds of wood （fir, larch, poplar, and eucalyptus） compared with commercial lignin were investigated using a thermogravimetric analyzer coupled to a Fourier-transform infrared spectrometer（TG-FTIR）. Kinetic parameters of lignin thermal cracking reaction, such as activation energy and pre-exponential factor, were calculated using a three-dimensional diffusion model. The carbon residue rate and activation energy of softwood lignin were higher than those of hardwood lignin, showing that the decomposition of the former is relatively more dif？cult than that of the latter during pyrolysis. The distinct characteristic peaks of small-molecule gases and oxygenated chemicals such as ethers, phenols, acids, aldehydes, and alcohols were observed near the maximum weight loss rate by analyzing the 3D IR spectrum of the gas phase products. The formation routes of the main gaseous products were discussed, and the following order of releasing amounts was noted： CO2〉CH4〉H2O〉CO. It is believed that these results will provide valuable information for the thermo-chemical conversion process of lignin from the point of view of feedstock.展开更多
This study was undertaken to determine the bending strength properties of off-cut Yellow Meranti wood by applying the finger jointed techniques. The finger orientations that were used in this study are vertical and ho...This study was undertaken to determine the bending strength properties of off-cut Yellow Meranti wood by applying the finger jointed techniques. The finger orientations that were used in this study are vertical and horizontal finger orientation. Specimens were bonded with PVAc （polyvinyl acetate）. The bending strength properties were determined by the three point and four point bending test method. The results show that vertical finger orientation has the higher mean of modulus of rupture and the modulus of elasticity value of 24.49 MPa （28.91 MPa） and 8,814 MPa （11,668 MPa） respectively. However, the tested specimen properties did not meet the minimum strength of the solid （control） specimens.展开更多
Are Austrian mountain wood harvesting techniques more ecological than techniques applied in the lowlands of southern Germany？ For this comparative study, the authors selected the area of Lower Bavaria for lowland woo...Are Austrian mountain wood harvesting techniques more ecological than techniques applied in the lowlands of southern Germany？ For this comparative study, the authors selected the area of Lower Bavaria for lowland wood, as a great deal of wood is imported from this region to western Austria. At first, the felling area is described for both regions, from forest site to sawmill. Thereby, the authors create mean values related to timber harvesting and transportation, which are applicable to the whole of western Austria and Lower Bavaria, southern Germany. Secondly, the eco-balance of mountain and lowland wood is established. It is based on the following impact categories： global warming potential, acidification potential, eutrophication potential, ozone depletion potential and non-renewable primary energy. The environmental impact is more expressive if the results are applied to a specific construction part （i.e., glued laminated timber-ceiling）. Our research study showed the eco-balance of western Austrian mountain wood is more favourable than the environmental impact of harvesting lowland wood in southern Germany.展开更多
Climate events pose major challenges to food production and the livelihoods of rural inhabitants in northern Laos, where upland rice using swidden production is an important crop. The onset of the rainy season in this...Climate events pose major challenges to food production and the livelihoods of rural inhabitants in northern Laos, where upland rice using swidden production is an important crop. The onset of the rainy season in this area is one such climate event, and it has occurred earlier and with less regularity in recent years. Not all households are able to cope with these changes. This study examines the ability of local farmers to cope with rice insufficiency. This investigation also clarifies household strategies in dealing with the climate event. We randomly interviewed 63 of 95 household heads, and performed a paired sample t test to examine the significance of differences in three household groups between the 2010 normal climate and the 2011 climate event. The groups were categorized according to rice selfsufficiency in 2011: groups I are households with rice self-sufficiency, group II are those facing a rice shortage of up to 3 months, and group III are those with insufficient rice for over 3 months. We also conducted a one-way ANOVA to examine the significance of differences in livelihood strategies among the three groups. We found that the household labor force was the most important factor in enhancing the villagers' ability to deal with the climate event and that the level of impact of that event shaped their coping strategies. Households with substantial labor force had more options for coping strategies than those with smaller ones. The villagers faced different levels of impact and adopted differentcoping strategies accordingly. Non-timber forest product collection was the principle livelihood strategy in response to non-climate factors such as education, access to health services, provision of equipment and clothing, and overcoming the impact of the climate event. Households heavily affected by the early rainy season onset tended to engage in intensive activities such as off-farm activity and outside work, rather than their major livelihood activities in the village(upland crop and livestock production).展开更多
This article analyzes the factors shaping commercial timber profit distribution in China’s Southern Collective Forest Region (hereinafter SCFR). The article first describes the setting and distribution of a national ...This article analyzes the factors shaping commercial timber profit distribution in China’s Southern Collective Forest Region (hereinafter SCFR). The article first describes the setting and distribution of a national harvest quota and analyzes its equity impacts on farmer households. Based on access mapping of the commercial timber commodity chain, profit distribution and mechanisms for controlling and maintaining access to profit are analyzed for different actors along the chain. The data show that farmers do not benefit to a great extent from the commerce, even if they are endowed with rights to manage and harvest forests and freely sell commercial timber in the region. There are a number of institutional and non-institutional factors that determine the extent of benefits farmers and other actors along the timber commodity chain can seek. Under current arrangements, the devolution of forest property in the SCFR does not ensure that farmer households benefit from commercial timber marketing. In order to stimulate farmers’ enthusiasm for forest rehabilitation and management, beyond the devolution of forest property, it is firstly necessary to take effective measures to improve farmer access to commercial timber profits.展开更多
文摘Pyrolysis properties of lignin separated from four different kinds of wood （fir, larch, poplar, and eucalyptus） compared with commercial lignin were investigated using a thermogravimetric analyzer coupled to a Fourier-transform infrared spectrometer（TG-FTIR）. Kinetic parameters of lignin thermal cracking reaction, such as activation energy and pre-exponential factor, were calculated using a three-dimensional diffusion model. The carbon residue rate and activation energy of softwood lignin were higher than those of hardwood lignin, showing that the decomposition of the former is relatively more dif？cult than that of the latter during pyrolysis. The distinct characteristic peaks of small-molecule gases and oxygenated chemicals such as ethers, phenols, acids, aldehydes, and alcohols were observed near the maximum weight loss rate by analyzing the 3D IR spectrum of the gas phase products. The formation routes of the main gaseous products were discussed, and the following order of releasing amounts was noted： CO2〉CH4〉H2O〉CO. It is believed that these results will provide valuable information for the thermo-chemical conversion process of lignin from the point of view of feedstock.
文摘This study was undertaken to determine the bending strength properties of off-cut Yellow Meranti wood by applying the finger jointed techniques. The finger orientations that were used in this study are vertical and horizontal finger orientation. Specimens were bonded with PVAc （polyvinyl acetate）. The bending strength properties were determined by the three point and four point bending test method. The results show that vertical finger orientation has the higher mean of modulus of rupture and the modulus of elasticity value of 24.49 MPa （28.91 MPa） and 8,814 MPa （11,668 MPa） respectively. However, the tested specimen properties did not meet the minimum strength of the solid （control） specimens.
文摘Are Austrian mountain wood harvesting techniques more ecological than techniques applied in the lowlands of southern Germany？ For this comparative study, the authors selected the area of Lower Bavaria for lowland wood, as a great deal of wood is imported from this region to western Austria. At first, the felling area is described for both regions, from forest site to sawmill. Thereby, the authors create mean values related to timber harvesting and transportation, which are applicable to the whole of western Austria and Lower Bavaria, southern Germany. Secondly, the eco-balance of mountain and lowland wood is established. It is based on the following impact categories： global warming potential, acidification potential, eutrophication potential, ozone depletion potential and non-renewable primary energy. The environmental impact is more expressive if the results are applied to a specific construction part （i.e., glued laminated timber-ceiling）. Our research study showed the eco-balance of western Austrian mountain wood is more favourable than the environmental impact of harvesting lowland wood in southern Germany.
基金funded by Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research (Kakenhi), Scientific Research (A)
文摘Climate events pose major challenges to food production and the livelihoods of rural inhabitants in northern Laos, where upland rice using swidden production is an important crop. The onset of the rainy season in this area is one such climate event, and it has occurred earlier and with less regularity in recent years. Not all households are able to cope with these changes. This study examines the ability of local farmers to cope with rice insufficiency. This investigation also clarifies household strategies in dealing with the climate event. We randomly interviewed 63 of 95 household heads, and performed a paired sample t test to examine the significance of differences in three household groups between the 2010 normal climate and the 2011 climate event. The groups were categorized according to rice selfsufficiency in 2011: groups I are households with rice self-sufficiency, group II are those facing a rice shortage of up to 3 months, and group III are those with insufficient rice for over 3 months. We also conducted a one-way ANOVA to examine the significance of differences in livelihood strategies among the three groups. We found that the household labor force was the most important factor in enhancing the villagers' ability to deal with the climate event and that the level of impact of that event shaped their coping strategies. Households with substantial labor force had more options for coping strategies than those with smaller ones. The villagers faced different levels of impact and adopted differentcoping strategies accordingly. Non-timber forest product collection was the principle livelihood strategy in response to non-climate factors such as education, access to health services, provision of equipment and clothing, and overcoming the impact of the climate event. Households heavily affected by the early rainy season onset tended to engage in intensive activities such as off-farm activity and outside work, rather than their major livelihood activities in the village(upland crop and livestock production).
文摘This article analyzes the factors shaping commercial timber profit distribution in China’s Southern Collective Forest Region (hereinafter SCFR). The article first describes the setting and distribution of a national harvest quota and analyzes its equity impacts on farmer households. Based on access mapping of the commercial timber commodity chain, profit distribution and mechanisms for controlling and maintaining access to profit are analyzed for different actors along the chain. The data show that farmers do not benefit to a great extent from the commerce, even if they are endowed with rights to manage and harvest forests and freely sell commercial timber in the region. There are a number of institutional and non-institutional factors that determine the extent of benefits farmers and other actors along the timber commodity chain can seek. Under current arrangements, the devolution of forest property in the SCFR does not ensure that farmer households benefit from commercial timber marketing. In order to stimulate farmers’ enthusiasm for forest rehabilitation and management, beyond the devolution of forest property, it is firstly necessary to take effective measures to improve farmer access to commercial timber profits.
