Objective] To analyze the aroma constituents of essential oils from Chi-monanthus praecox. [Method] Extracted by microwave-assisted hydrodistil ation （MAHD）, aroma constituents of essential oils of Chimonanthus prae...Objective] To analyze the aroma constituents of essential oils from Chi-monanthus praecox. [Method] Extracted by microwave-assisted hydrodistil ation （MAHD）, aroma constituents of essential oils of Chimonanthus praecox flowers were analyzed by gas chromatography-mass spectrometry （GC-MS）. Normalization method was used to determine the constituents quantitatively. [Result] Total y 27 compounds were identified, accounting for 98.85% of total amounts. The main aroma con-stituents are terpenes, aldehydes, esters, alcohols and hydrocarbons. Main compo-nents with relative percentage over 5% are germacrene D （25.62%）, bornyl acetate （16.71%）, caryophyl ene （10.51%）, cis-α-ocimene （5.18%）, γ-elemene （8.05%）, β-linalool （5.01%）, 1-ethenyl-1-methyl-2,4-bis （1-methylethenyl）-cyclohexane （7.18%） and 2,3,4,4α,5,6-hexahydro-1,4αdimethyl-7-（1-methylethyl）-naphthalene （5.20%）. [Conclu-sion] The study provided a theoretical reference for the development and utilization of Chimonanthus praecox resources.展开更多
Wood transportation begins from the landing or the forest road where the processed wood assortments are placed, they are loaded on trucks and then transported to the wood-working industry and/or the consumption center...Wood transportation begins from the landing or the forest road where the processed wood assortments are placed, they are loaded on trucks and then transported to the wood-working industry and/or the consumption centers. Wood transportation in Greece is carried out, almost exclusively, by trucks. The aim of this study is to analyze the evolution of timber trucking in Greece through the analysis of wood transportation waybills. A total of 1,471 waybills have been collected and analyzed that cover the period 1981-2008 from nine of the most productive and representative forest districts in Greece, in terms of timber production. The final dataset included information on the type and technical characteristics of truck types, the transported wood quantities and haulage distances. Furthermore, data on the wood transportation cost for the year 2010 have been collected and analyzed. According to the results, the number of two-axle trucks that dominated in the 1980s is reducing rapidly, mostly to the benefit of larger three-axle and four-axle trucks. More than three quarters （77%） of wood transportation is conducted in the period June-October. Mean vehicle load per vehicle type differs between conifer and broadleaved species from 7.1% up to 23.9%. Transportation of stacked wood with semitrailers is conducted with overloaded trucks, which could entail serious problems for public safety and the condition of road network. New design standards will enhance serviceability of the wood transportation routes and environmental protection.展开更多
基金Supported by the Research Fund from Guizhou Academy of Agricultural Science(2013009)Innovation Capacity Platform Construction Project of Guizhou Science and Technology Department(20104008)~~
文摘Objective] To analyze the aroma constituents of essential oils from Chi-monanthus praecox. [Method] Extracted by microwave-assisted hydrodistil ation （MAHD）, aroma constituents of essential oils of Chimonanthus praecox flowers were analyzed by gas chromatography-mass spectrometry （GC-MS）. Normalization method was used to determine the constituents quantitatively. [Result] Total y 27 compounds were identified, accounting for 98.85% of total amounts. The main aroma con-stituents are terpenes, aldehydes, esters, alcohols and hydrocarbons. Main compo-nents with relative percentage over 5% are germacrene D （25.62%）, bornyl acetate （16.71%）, caryophyl ene （10.51%）, cis-α-ocimene （5.18%）, γ-elemene （8.05%）, β-linalool （5.01%）, 1-ethenyl-1-methyl-2,4-bis （1-methylethenyl）-cyclohexane （7.18%） and 2,3,4,4α,5,6-hexahydro-1,4αdimethyl-7-（1-methylethyl）-naphthalene （5.20%）. [Conclu-sion] The study provided a theoretical reference for the development and utilization of Chimonanthus praecox resources.
文摘Wood transportation begins from the landing or the forest road where the processed wood assortments are placed, they are loaded on trucks and then transported to the wood-working industry and/or the consumption centers. Wood transportation in Greece is carried out, almost exclusively, by trucks. The aim of this study is to analyze the evolution of timber trucking in Greece through the analysis of wood transportation waybills. A total of 1,471 waybills have been collected and analyzed that cover the period 1981-2008 from nine of the most productive and representative forest districts in Greece, in terms of timber production. The final dataset included information on the type and technical characteristics of truck types, the transported wood quantities and haulage distances. Furthermore, data on the wood transportation cost for the year 2010 have been collected and analyzed. According to the results, the number of two-axle trucks that dominated in the 1980s is reducing rapidly, mostly to the benefit of larger three-axle and four-axle trucks. More than three quarters （77%） of wood transportation is conducted in the period June-October. Mean vehicle load per vehicle type differs between conifer and broadleaved species from 7.1% up to 23.9%. Transportation of stacked wood with semitrailers is conducted with overloaded trucks, which could entail serious problems for public safety and the condition of road network. New design standards will enhance serviceability of the wood transportation routes and environmental protection.
