Beobachtungen in der Nähe von kohleverbrennenden Kraftwerken in Pennsylvania/USA     

D. D. Davis  F. A. Wood  R. J. Hutnik  G. C. Wiedersum  W. R. Rossman 《European Journal of Forest Research》1984,103(1):61-73

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老外教你做生意     

Elizabeth Baldwin 《国际木业》2003,(12):47-51

在我刚刚加入Maruhon的时候,公司总裁对我说:“信息是生意的生命之源”,信息流越多,生意做得越旺。在经历了15年的商场生涯后,我发现这是一句至理箴言。你学得越多,知道得越多,分享的越多,你就越能够找到对双方合作的基点。因此,请谨记,交流是促成生意成功的关键。  相似文献   

Intratree Variability of Tensile Strength Parallel to Grain in Chinese Fir and I-214 Poplar from Plantation     

XU Ming REN Haiqing LI Xiazhen Research Institute of Wood Industry  Chinese Academy of Forestry  Beijing  P.R.China 《中国林业科技(英文版)》2007,(3)

The variation of tensile strength parallel to grain in Chinese fir and I-214 poplar wood from plantations was studied in this paper. Aaccording to the national standards The Testing Methods for Physical and Mechanical Properties of Wood (GB 1927 to 1943 ? 1991), the small clear wood samples were cut and tested, which represent the south and north of trees with heights of 1.3, 3.3, 5.3 and 7.3 m. The results showed: the tensile strength parallel to grain of the north wood was higher than that of south wood. ANOVA shows that the tensile strength parallel to the grain with height is of significant difference (at 0.05 level).  相似文献   

Preparation and Characterization of Phenolated Wood Using Sulfuric Acid as a Catalyst I: Liquefaction Behavior of Plantation Wood     

Atsushi IKEDA 《中国林业科技(英文版)》2002,(4)

Chinese fir (Cunninghamia lanceolata) and poplar (Populus spp.) wood meal were phenolated in the presence of sulfuric acid used as a catalyst. The effects of reaction time and reaction temperature on the wood liquefaction were investigated. The results showed that the reaction temperature had the greater influence on the residue content than reaction time. Additionally, the liquefaction curve for the Chinese fir and Poplar were similar in general.  相似文献   

Overstory and shrub effects on natural regeneration processes in native Pinus radiata stands     

Michael J. O&#x;Brien  Kevin L. O&#x;Hara  Nadir Erbilgin  David L. Wood 《Forest Ecology and Management》2007,240(1-3):178-185

Native Monterey pine (Pinus radiata D. Don) stands on the Monterey peninsula have been significantly modified by natural and anthropogenic disturbances. The exclusion of fire and the introduction of pitch canker (caused by Fusarium circinatum Nirenberg & O’Donnell) created a need for the examination of these changing ecosystems with respect to regeneration, especially as these stands reach mature ages. We established 210 plots on 35 transects distributed throughout five stands in order to describe the current stand structure and quantify the extent and condition of regeneration. The results indicated that Monterey pine seedling establishment varies throughout the peninsula depending on percent canopy cover, duff and litter depth, and percent shrub cover while seedling growth is influenced by percent shrub cover. Canopy cover was also found to inversely influence shrub cover. Our study highlights the importance of understory removal to increase Monterey pine regeneration and seedling growth as canopy cover decreases, especially in areas where coast live oak (Quercus agrifolia Nee) and poison-oak (Toxicodendron diversilobum E. Greene) are abundant.  相似文献   

Pilot Study to Examine Radial Variation in Annual Ring Width, Density and Shrinkage     

URAKAMI Hiroyuki  HIRAKAWA Yasuhiko  YAMASHITA Kana 《中国林业科技(英文版)》2003,(4)

The annual ring width, density and shrinkage variation from pith to bark in Chinese fir (Cunninghamia lanceolata) and Boka sugi (Cryptomeria japonicd) were studied and compared. The results show that the ring width decreased sharply from pith to bark for Chinese fir. However, the ring width variation pattern for Boka sugi followed a different way, i.e., the ring width decreased to the fifth ring, increased to the tenth ring, decreased again to the fifteenth, and then increased to the twentieth, where it became constant. The large variations of Boka sugi appeared to show the maintenance of fast growth for many years. The annual ring mean density of Chinese fir increased gradually from pith to bark. However, the density changes for Boka sugi indicated the opposite trend, i.e., the mean density decreased gradually from pith to bark. The former showed a pattern as the same as a pine and a larch, and the latter was often found in a cedar and a cypress. The longitudinal shrinkage in juvenile wood was much hig  相似文献   

Growth and nutrient accumulation of Brazil nut trees (Bertholletia excelsa) in agroforestry at different fertilizer levels     

G?tz Schroth  Maria do Socorro Souza da Mota  Maria Elizabeth de Assis Elias 《林业研究》2015,26(2):347-353

The Brazil nut tree(Bertholletia excelsa) is a frequent component of agroforestry systems in the Amazon because of its adaptation to nutrient-poor upland soils and multiple uses.We investigated the aboveground biomass production(kg dry weight),nutrient uptake and requirements(N,P,Ca,Mg,K) of Brazil nut trees of different sizes grown under agroforestry conditions and fertilized at different levels.Eight of 70 experimental trees with different size were harvested and stem,branches and leaves were separated.Nutrient contents were determined for three trees of varying size.Average tree growth was fast,but variability was high,suggesting considerable potential for the improvement of this economically important species.The trees responded to increased levels of fertilizer and lime with significantly increased foliar nutrient contents and growth,probably because of the improved availability of Mg and Ca for which the species seems to have a relatively high demand.In contrast to Brazil nut trees grown in forest or dense plantations,the agroforestry trees invested a substantial part of their biomass and nutrients in large branches and developed spreading crowns.To improve stem form,reduce competition with associated crops for light and recycle nutrients,regular pruning of lower branches or planting arrangements that favor self-pruning are recommended.These measures would also increase the recycling of Ca and Mg,large quantities of which are contained in the branches.  相似文献   

Hematologic and biochemical reference intervals for adult Friesian horses from North America          下载免费PDF全文

Saundra H. Sample  Katherine M. Fox  Denise Wunn  Elizabeth Roth  Kristen R. Friedrichs 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2015,44(2):194-199

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Enhanced inactivation of avian influenza virus at ?20°C by disinfectants supplemented with calcium chloride or other antifreeze agents     

Jiewen Guan  Maria Chan  Brian W. Brooks  Elizabeth Rohonczy 《Canadian journal of veterinary research》2015,79(4):347-350

Avian influenza outbreaks have occurred during winter months, and effective disinfection of poultry premises at freezing temperatures is needed. The commercial disinfectants Virkon and Accel, supplemented with an antifreeze agent [propylene glycol (PG), methanol (MeOH), or calcium chloride (CaCl₂)], were evaluated for their effectiveness in killing avian influenza virus (AIV) at −20°C or 21°C. An AIV suspension was applied to stainless steel disks, air-dried, and covered with a disinfectant or antifreeze agent for 5 to 30 min. Virkon (2%) and Accel (6.25%) with 30% PG, 20% MeOH, or 20% CaCl₂ inactivated 6 log₁₀ AIV within 5 min at −20°C and 21°C. At these temperatures PG and MeOH alone did not kill AIV, but the 20% CaCl₂ solution alone inactivated 5 log₁₀ AIV within 10 min. The results suggested that CaCl₂ is potentially useful to enhance the effectiveness of disinfection of poultry facilities after outbreaks of AIV infection in warm and cold seasons.  相似文献   

Erythema multiforme associated with zonisamide in a dog          下载免费PDF全文

Amanda L. Ackermann  Linda A. Frank  Michael F. McEntee  Elizabeth R. May 《Veterinary dermatology》2015,26(5):391-e89

This report describes a dog that developed erythema multiforme in temporal association with administration of the sulphonamide‐based anticonvulsant drug zonisamide. Similar adverse drug reactions have been associated with sulphonamide antimicrobial drugs. Caution should be exercised when prescribing this medication for dogs with known hypersensitivity to sulphonamides.  相似文献