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分散固相萃取—气相色谱/串联质谱法测定竹笋中38种持久性有机污染物
竹笋 多环芳烃 多氯联苯 有机氯农药
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2023/6/5
建立了同时测定竹笋中9种多环芳烃(PCBs)、16种多氯联苯(PAHs)和13种有机氯农药(OCPs)的分散固相萃取-气相色谱法-串联质谱(DSPE-GC-MS/MS)分析方法。竹笋样品经乙腈提取,以无水MgSO_4、弗罗里硅土和十八烷基键合硅胶吸附剂(C18)作为分散固相萃取净化剂净化,经气相色谱-串联质谱测定,外标法定量。结果表明,方法实现了对38种持久性有机化合物的分离和定量,分析物含量在2...
Energy consumption of chipper coupled to a universal wheel skidder in the process of chipping wood
chip chipper chipping energy consumption power of cutting
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2015/3/27
The chipper for chips is an energy consuming machine. Many factors influence the result of chipping which influence the whole process. The paper deals with the process of wood chipping by a chipper in...
Comparison of automatic and interactive thresholding of hemispherical photography
image analysis LIA for Win32 light environment operator bias operator variation
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2015/3/27
This study presents the effects of operator bias and variation in interactive thresholding on the estimation of light environment using hemispherical photography. Twenty-one hemispherical photographs ...
Spatially constrained harvest scheduling for strip allocation under Moore and Neumann neighbourhood adjacency
integer programming Moore and Neumann neighbourhood adjacency Shelterwood management strip cutting
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2015/3/27
Adjacency constraints can be represented by Moore or Neumann neighbourhood adjacency, depending upon how candidate neighbours are assigned at corners adjacent to the target cell. Considering Moore and...
Density of juvenile and mature wood of selected coniferous species
density juvenile wood larch mature wood Norway spruce Scots pine
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2015/3/27
The objective of research was to determine the density of juvenile (JW) and mature wood (MW) of selected coniferous species growing in the Czech Republic. The research included the wood of Norway spru...
Harvest scheduling with spatial aggregation for two and three strip cut system under shelterwood management
aggregation connectivity GIS optimization model spatial forest planning wind-thrown risk
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2015/3/27
We propose a spatial aggregation method to solve an optimal harvest scheduling problem for strip shelterwood management. Strip shelterwood management involves either a two-cut system with a preparator...
Detrending ability of several regression equations in tree-ring research: a case study based on tree-ring data of Norway spruce (Picea abies [L.])
radial increment growth functions empirical fitting tree-ring indices dendroclimatology
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2015/3/27
The aim of this study was to investigate tree-ring width variability and to distinguish groups of trees with similar growth trends in order to study tree growth responses to various stand and site con...
Calculating the correction factor of skidding distance based on forest road network
real skidding distance theoretical skidding distance correction factor Chafrood forest
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2015/3/27
Average skidding distance for forest stands is an important parameter for the determination of the optimum road density and spacing. In this research the real mean skidding distance and theoretical me...
A linkage among whole-stand model, individual-tree model and diameter-distribution model
forecast combination linkage parameter recovery stand growth and yield model
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2015/3/19
Stand growth and yield models include whole-stand models, individual-tree models and diameter-distribution models. In this study, the three models were linked by forecast combination and parameter rec...
Phenology of four broad-leaved forest trees in a submountain beech forest
submountain beech forest phenology vegetative phenological phases
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2015/3/17
The phenology of four deciduous forest tree species (Carpinus betulus L., Fagus sylvatica L., Quercus dalechampii Ten., Tilia cordata Mill.) was studied in a submountain beech forest stand in Central ...
Productivity and cost of manual felling with a chainsaw in Caspian forests
chainsaw working efficiency unit cost
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2015/3/17
A field production study was conducted for a manual harvesting system using a chainsaw in a Caspian hardwood forest site. A selective cut was performed on a 42-hectare tract with an average slope of 3...
Assessment of tree layer biomass and structure using aerial photos in lake catchments of the 妘mava Mts.
allometry altitudinal gradient Bohemian Forest
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2015/3/16
The combination of georeferenced colour aerial photos and limited field measurements of individual trees was used to determine tree stand biomass in forests of prevailing Norway spruce. The technique ...
Development of foliage biomass of young spruce and beech stands in the mountain water balance research area
Norway spruce European beech young stand
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2015/3/16
The investigation of foliage biomass development including LAI and the growth of spruce and beech stands in the juvenile stage (age 1 to 21 years) represents a special complementary study to long-term...
Photosynthetic response to different light intensities and water status of two main Nothofagus species of southern Patagonian forest, Argentina
Nothofagus shade photosynthesis
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2015/3/16
Net photosynthetic rate (A) and stomatal conductance (gs) of leaves of Nothofagus pumilio and N. an-tarctica seedlings were measured at different photosynthetic photon flux densities (PPFDs, 20, 150, ...
Regeneration and game damage in the Kru歯?hory Mts. assessed on the basis of National Forest Inventory of the Czech Republic
National Forest Inventory game damage Kru歯 ?hory Mts.
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2015/3/16
In 2001?004 National Forest Inventory was realized in the Czech Republic. A great number of variables was measured giving rise to an extensive information database that can be used to assess the state...