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oak高速冲床噪声治理

噪声与振动控制 1994年第5期 13-13页

作者：吕玉恒

ＯＡＫ高速冲床噪声治理为冲制空调器薄片零部件，上海家用空调器总厂从美国进口了三台ＯＡＫ高速冲床。该冲床外形Ｘ寸长Ｘ宽Ｘ高一５９４９Ｘ３５６８Ｘ３１９０（ｍｍ），噪声高达１０８ｄＢ（Ａ）。它不仅直接危害操作者，而且给整... 详细信息

ＯＡＫ高速冲床噪声治理为冲制空调器薄片零部件，上海家用空调器总厂从美国进口了三台ＯＡＫ高速冲床。该冲床外形Ｘ寸长Ｘ宽Ｘ高一５９４９Ｘ３５６８Ｘ３１９０（ｍｍ），噪声高达１０８ｄＢ（Ａ）。它不仅直接危害操作者，而且给整个车间带来严重的噪声污染，３台同时...

关键词：噪声治理高速冲床 oak

oak中标努奥罗(中国)公司办公楼及厂房项目

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机电信息 2011年第16期 8-8页

近日,oak成功中标努奥罗(中国)公司办公楼及厂房空调项目。作为散热器制造行业的领先企业,努奥罗在国内拥有多个生产基地,数个国家标准实验室和总面积达20万m2的厂房。此次项目包含办公楼和厂房,其中厂房分2层,共8个车间。各个车间均有... 详细信息

近日,oak成功中标努奥罗(中国)公司办公楼及厂房空调项目。作为散热器制造行业的领先企业,努奥罗在国内拥有多个生产基地,数个国家标准实验室和总面积达20万m2的厂房。此次项目包含办公楼和厂房,其中厂房分2层,共8个车间。各个车间均有不同的特殊要求:除湿(相对湿度在每个车间均有不同的要求)、热回收、新风等,若按日常设计方案只采用表冷器除湿,不能完全满足使用要

关键词：奥罗 oak 厂房地源热泵机组办公楼中华人民共和国

2014亚洲勒芒赛麟蹄开赛oak道达尔车队首战告捷

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汽车与配件 2014年第34期 20-20页

近日,2014亚洲勒芒系列赛在韩国麟蹄郡隆重开赛。作为上一届总冠军,车手程飞和董荷斌重新回到战斗状态,并带领oak道达尔车队英勇夺冠。oak道达尔车队参赛赛车是由Onroak Automotive研发的1号Morgan-Judd LM P2赛车,在道达尔润滑油(中国... 详细信息

近日,2014亚洲勒芒系列赛在韩国麟蹄郡隆重开赛。作为上一届总冠军,车手程飞和董荷斌重新回到战斗状态,并带领oak道达尔车队英勇夺冠。oak道达尔车队参赛赛车是由Onroak Automotive研发的1号Morgan-Judd LM P2赛车,在道达尔润滑油(中国)有限公司的支持下,这对中国搭档向人们证明他们在韩国所向披靡。

关键词：道达尔 oak 勒芒总冠军战斗状态 Automotive

Occurrence and Culture of Mycorrhizal Fungi Associated with oaks in Dandong Region, Liaoning Province

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Pedosphere 2005年第2期15卷 232-237页

作者： WANGHui DAILi-Min YANGBao-Shan LANGQing-Long GUHui-Yan InstituteofAppliedEcology ChineseAcademyofSciencesShenyang110016（China）／／GraduateSchoolofChineseAcademyofSciencesBeijing100039（China） InstituteofAppliedEcology ChineseAcademyofSciencesShenyang110016（China） InstituteofLiaoningSericulturalScience Fengcneng118100（China） InstituteofAppliedEcology ChineseAcademyofSciencesShenyang110016（China）／／CollegeofForestryNortheastForestryUniversityHarbin150040（China）

With both field investigation and pure culture experiments, the occurrence and optimal essential growth of mycorrhizal fungi with oaks in Dandong Region of Liaoning Province, China were investigated from 1997-2002 A total of 36 species of mycorrhizal fungi associated with oaks were observed. The results showed that the occurrence of mycorrhizal fungi was related to tree species, tree ages, and months of the year, with at least 20 fungi species being associated with more than two oak species. The highest Sim…

关键词： mycorrhizal fungi rnycorrhizal relationship oak pure culture

oakS(QUERCUS SPP.)IN NORTHEAST CHINA

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Journal of Northeast Forestry University 1990年第1期1卷 1-10页

作者： Chen DakeNortheast Forestry University, Harbin 150040, P. R. China 1. Northeast Forestry University 150040 Harbin P. R. China

There arc eight species and four varieties of oak in northeast China. This paper reports and describes the distribution and phylocoenogenesis of the Korean pine-broadleaved mixed forest and the mongolian oak formation. The close relationship between the flora of Ussuli—Amur region and Japan is discussed. Analyses of heat and energy balance, and biomass of mongolian oak forests arc provided. Many measurements indicate that, in a nonclosed stand, the wood production of a stand is positively correlated with leaf area index (LAI).

关键词： oak Phytococnogenesis Biomass Heat and energy balance

Seed loss before seed predation: experimental evidence of the negative effects of leaf feeding insects on acorn production

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Integrative Zoology 2018年第3期13卷 238-250页

作者： Tara CANELO Álvaro GAYTÁN Guillermo GONZÁLEZ-BORNAY Raul BONAL Forest Research Group INDEHESAUniversity of ExtremaduraPlasenciaSpain DITEG Research Group University of Castilla-La ManchaToledoSpain CREAF Cerdanyola del VallèsCataloniaSpain

Insect herbivory decreases plant fitness by constraining plant growth,survival and reproductive *** studies on the effects of herbivory in trees rely on correlational inter-individual comparisons and could,thus,be affected by confounding factors linked to both herbivory and plant *** the Mediterranean Holm oak(Quercus ilex)as a study model,we followed an experimental approach in which leaf-feeding insects(mainly Lepidoptera caterpillars)were excluded from some shoots in all study *** subjected to herbivore exclusion exhibited lower defoliation rates and produced more acorns than control *** constrained shoot growth throughout the study period,but had no effect on the number of female flowers produced per *** production was,however,lower in control shoots due to their higher abortion rates,and also to their greater mortality risk during summer drought,as shoots with fewer leaves were less likely to *** reaction to herbivory inhibits certain physiological pathways involved in plant growth,which,together with the effects of physical damage,reduces the amount and efficiency of the photosynthetic *** increases their vulnerability to environmental stresses,such as water deficit,which limit resource *** is likely a key factor affecting oak regeneration,as it may be a significant source of seed loss prior to pre-dispersal acorn *** experimental studies could help to elucidate its effects in contrasting *** Mediterranean regions,the harsher droughts predicted by climate change models could worsen the effects of insect herbivory on oak reproductive output.

关键词： drought stress insect defoliation oak seed abortion shoot mortality

Exploring the factors affecting carbon and nutrient concentrations in tree biomass components in natural forests,forest plantations and short rotation forestry

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Forest Ecosystems 2018年第4期5卷 498-515页

作者： Roque Rodriguez-Soalleiro Cristina Eimil-Fraga Esteban Gomez-Garda Juan Daniel Garcia-Villabrille Alberto Rojo-Alboreca Fernando Munoz Nerea Oliveira Hortensia Sixto Cesar Perez-Cruzado Sustainable Forest Management Unit (UXFS) Department of Plant Production and Engineering ProjectsUniversidade de Santiago de Compostela (USC)Rua Benigno LedoCampus Terra27002 LugoSpain Centro de Investigacion Forestal de Lourian Xunta de Galicia.Carretera de Marin km 3.536153 PontevedraSpain Sustainable Forest Management Unit (UXFS) Department of Agroforestry EngineeringUniversldade de Santiago de Compostela (USC)LugoSpain Universidad de Concepcion Facultad de Ciencias ForestalesVlctona631 ConcepcionChile Forest Systems and Resources Department Centre for Forest ResearchINIACrta. de la Coruna km 7.528040MadridSpain

Background: Coupling biomass models with nutrient concentrations can provide sound estimations of carbon and nutrient contents, enabling the improvement of carbon and nutrient balance in forest ecosystems. Although nutrient concentrations are often assumed to be constant for some species and specific tree components, at least in mature stands,the concentrations usually vary with age, site index and even with tree density. The main objective of this study was to evaluate the sources of variation in nutrient concentrations in biomass compartments usually removed during harvesting operations, covering a range of species and management conditions: semi-natural forest, conventional forest plantations and short rotation forestry(SRF). Five species(Betula pubescens, Quercus robur, Eucalyptus globulus, Eucalyptus nitens and Populus spp.) and 14 genotypes were considered. A total of 430 trees were sampled in 61 plots to obtain 6 biomass components:leaves, twigs, thin branches, thick branches, bark and wood. Aboveground leafless biomass was pooled together *** concentrations of C, N, K, P, Ca, Mg, S, Fe, Mn, Cu, Zn and B were measured and the total biomass of each sampled tree and plot were determined. The data were analysed using boosted regression trees and conventional ***: The main sources of variation in nutrient concentrations were biomass component > > genotype(species) ≈ age >tree diameter. The concentrations of Ca, Mg and K were most strongly affected by genotype and age. The concentrations of P, K, Ca, Mg, S and Cu in the wood component decreased with age, whereas C concentrations increased, with a trend to reach 50% in the older trees. In the SRF, interamerican poplar and P. trichocarpa genotypes were comparatively more efficient in terms of Ca and K nutrient assimilation index(NAI)(+65-85%) than eucalypts, mainly because leafless biomass can be removed. In the conventional eucalypt plantations(rotation 15 years), debarking the wood at logg

关键词： Nutrient removal Biomass crops Poplar genotypes Eucolyptus oak Birch Plantation sustainability

Recent shifts in shade tolerance and disturbance traits in forests of the eastern United States

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Ecological Processes 2019年第1期8卷 391-401页

作者： Brice B.Hanberry Rocky Mountain Research Station USDA Forest ServiceRapid CitySD 57702USA

Background:Current forests of the eastern USA have the potential to succeed in composition to more shade-tolerant ***,long-term processes of transition from fire-tolerant tree species to fire-sensitive species and effects of current land use on forests may interfere with successional ***:I examined if forests in three regions have increased in shade tolerance and if life history strategy groups that represent response to disturbance(i.e.,fire-tolerance,early-successional species based on low shade tolerance,mid-successional species,late-successional species,and trees valued for traits related to short harvest rotations)have changed,using Forest Inventory and Analysis surveys,adjusted for comparison,and generalized linear mixed models to assess approximately 30 year trends,with adjustments to equalize different survey ***:Although statistically significant,a slight increase of 2 to 4%in regional mean shade tolerance may not be ecologically *** the central East,mid-successional species replaced early-successional species and early-successional species replaced fire-tolerant oaks,resulting in an overall shift from fire-tolerant oaks to mid-successional *** fire-tolerant pine species and increased planted pine species were the major changes in the northern Southeast and Coastal ***:The successional process of increased composition by shade-tolerant species over time was overshadowed by land use changes that resulted in decreased fire-tolerant species and increased planted ***,frequent land use disturbance may continue to prevent the slow progress of compositional succession to very shade-tolerant species.

关键词： Disturbance Eastern United States Fire Land use Mesophication oak Pine Succession Traits

Nutrients in litterfall,forest floor and mineral soils in two adjacent forest ecosystems in Greece

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Journal of Forestry Research 2020年第1期31卷 291-301页

作者： Panagiotis Michopoulos Kostas Kaoukis George Karetsos Theodoros Grigoratos Constantini Samara H.A.O.DEMETER-Institute of Mediterranean Forest Ecosystems Terma Alkmanos11528 AthensGreece Department of Chemistry Environmental Pollution Control LaboratoryAristotle University Thessaloniki54124 ThessalonikiGreece Sustainable Transport Unit(STU) Institute for EnergyTransport and Climate Change(IETC)Joint Research Centre(JRC)Via E Fermi 274921027 IspraItaly

The fluxes of masses and the nutrients Ca,Mg,K,N,P and S were determined in the litterfall of two adjacent forest ecosystems of Hungarian oak(Quercus frainetto L.)and European beech(Fagus sylvatica L.)in a mountainous area of northeastern Greece in 2010–*** foliar litterfall for both species reached about 70%of the total litterfall,and was significantly higher from the other two fractions(woody and rest litterfall).The fluxes of masses and nutrients were compared between ecosystems for each fraction *** one significant statistical difference was found,that of K in the woody *** addition,the stocks of masses and nutrients were calculated in the forest floors and mineral soils of the two ***,the stocks of nutrients in the forest floors and mineral soils were compared between *** the L horizon of the forest floors,statistical differences,as a result of species effect,were found for the stocks of Ca and *** the FH horizons,the masses and all the nutrient stocks differed significantly,as the beech plot had much higher quantities of organic matter and *** higher quantities were probably due to low soil temperatures(microclimate)and high acidity in the beech plot(species effect)that slowed down *** the mineral soils,the propagation of random error derived from random errors of the individual soil layers was an important factor in the statistical *** of the soil acidity in the beech plot,the stocks of exchangeable base cations were significantly higher in the oak plot,whereas the other nutrient stocks did not differ.

关键词： Beech oak Litterfall Forest floor Mineral soil Nutrients