Báo cáo lâm nghiệp: "Detection of cavitation events upon freezing and of water in stems using ultrasound technique" pdf

... (1983) In: Xylem Structure and the Ascent of Sap. Springer-Verlag, Berlin, pp. 143 Detection of cavitation events upon freezing and thawing of water in stems using ultrasound ... place upon the freezing and the thawing of water in vessels. In fact, the existence of cavitative events as a consequence of cycles of freezing...

Ngày tải lên: 09/08/2014, 04:20

... blunt cutting edge does not cut the material in the process of chip cutting. It is mainly in the plain passing the lowest point of the cutting edge but it is also in the plain lying a little ... back and leading surfaces against the machined surface. Defining the value of individual parts of force F is quite difficult and depends on many aspects. e part of force F in...

Ngày tải lên: 07/08/2014, 03:22

... 207–216. [38] Yagüe S., Silviculture and production of stone pine (Pinus pinea L.) stands in the province of Avila (Spain), Proceedings of the IUFRO Meeting on Mountain Silviculture, Valsaín, 1984, ... model using the weigted least squares (WLS) for the site index (SI) (a) and the stand age (b). Figure 4. Ordinary kriging prediction of the age of the stand obtained using E...

Ngày tải lên: 07/08/2014, 16:20

... level of 20 min per tree to something in the order of one minute per tree, thus enabling the method to become more efficient and potentially usable in routine forest inventory. With improvements in ... abies 1. INTRODUCTION The commercial value of logs for processing into solid wood is mainly determined by the size and straightness of the tree stem, and the number and size...

Ngày tải lên: 07/08/2014, 16:21

... [14] and, perhaps, the expanding internodes of young stems. Thus, a certain number of young leaves and internodes may need to have been devel- oped in order for the auxin-dependent pre-condition ... variation in the sets of data. The number of fusiform cells in the radial files on the xylem side of the cambium varied with the time of year, increasing to a maximum of a...

Ngày tải lên: 08/08/2014, 00:22

... legitimating our approach consisting in reducing the number of input data. The validation was made on a large range of measured PACL values, ranging from 1.33% to 79.70%, including very closed stand ... (with an individual crown). In the study areas and first buffers pooled, a total of 1 182 and 177 crowns corresponding to 1 589 and 227 stems were measured in Plots 1 and...

Ngày tải lên: 08/08/2014, 00:22

... regardless of index value and not the inverse. Therefore, when dividing a tree ring into E and L zones, the aim of this method will be to classify cells in a radial cell file which contains multiple ... triangle, and square, respectively. The vertical bars indicate the mean beginning position of each intra-ring zone of tree rings which contain no problematic zone. Y-axis is a...

Ngày tải lên: 08/08/2014, 00:22

... at generating haploid lines of Poplar species for genetic manipulation and breeding programs K.E. Wolter B.H. McCown Department of Horticulture, University of Wisconsin, Madison, ... making monitoring extremely difficult. Discussion and Conclusion The conclusions from the results obtained to date are that production and mainte- nance of haploid ti...

Ngày tải lên: 09/08/2014, 04:20

... tube. Stream lines may appear irregular and fractal, reflecting the constrictions and enlarging nodes of the settling particles and cells (Batchelor, 1967). Rings on eitheir side of ... created by inanimate particles settling in the fluid (cf. Fig. 1 A-E). In suspension cultures, where viscosity is increased by high levels of sucrose, myoino...

Ngày tải lên: 09/08/2014, 04:20

... &dquo; Summary Detection of wavy grain on standing maples Portable hardness tester and ultrasonic method were used to differentiate on standing trees wavy grained maples. Only ... concepts in the de.rign of experiments, 2nd edition. Ed. Holt Rinehart, Winston. HO FFME Y ER P., The pilodyn instrumerzt as a non-destructive tester of the shock...

Ngày tải lên: 09/08/2014, 06:21