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Different Vertical (different + vertical)
Selected AbstractsContinuous Flow Radio Frequency Heating of Water and Carboxymethylcellulose SolutionsJOURNAL OF FOOD SCIENCE, Issue 1 2003Q. Zhong ABSTRACT Tap water and 1% CMC solutions were heated in a 40.68 MHz, 30 kW continuous flow radio frequency unit. Temperatures at different vertical and radial locations were monitored by fiber optic probes during batch heating of tap water and 1% CMC solution. Temperatures at different locations were similar during batch heating of tap water, while a significant temperature difference was observed for 1% CMC solutions, with the temperature close to the wall being higher than that at the center. Similar trends were observed during continuous heating of tap water and 1% CMC solutions, with Twall > TR/2 > Tcenter for the latter. The observations were a result of different dielectric properties of these 2 fluids, as well as the fluid flow characteristics during continuous heating. [source] Structural acclimation and radiation regime of silver fir (Abies alba Mill.) shoots along a light gradientPLANT CELL & ENVIRONMENT, Issue 3 2003A. CESCATTI ABSTRACT Shoot architecture has been investigated using the ratio of mean shoot silhouette area to total needle area ( ) as a structural index of needle clumping in shoot space, and as the effective extinction coefficient of needle area. Although can be used effectively for the prediction of canopy gap fraction, it does not provide information about the within-shoot radiative regime. For this purpose, the estimation of three architectural properties of the shoots is required: needle area density, angular distribution and spatial aggregation. To estimate these features, we developed a method based on the inversion of a Markov three-dimensional interception model. This approach is based on the turbid medium approximation for needle area in the shoot volume, and assumes an ellipsoidal angular distribution of the normals to the needle area. Observed shoot dimensions and silhouette areas for different vertical and azimuth angles (AS) are used as model inputs. The shape coefficient of the ellipsoidal distribution (c) and the Markov clumping index (,0) are estimated by a least square procedure, in order to minimize the differences between model prediction and measurements of AS. This methodology was applied to silver fir (Abies alba Mill.) shoots collected in a mixed fir,beech,spruce forest in the Italian Alps. The model worked effectively over the entire range of shoot morphologies: c ranged from 1 to 8 and ,0 from 0·3 to 1 moving from the top to the base of the canopy. Finally, the shoot model was applied to reconstruct the within-shoot light regime, and the potential of this technique in upscaling photosynthesis to the canopy level is discussed. [source] Home Range Size of Sympatric Squirrel Species Inhabiting a Lowland Dipterocarp Forest in Malaysia,BIOTROPICA, Issue 2 2001A. A. Saiful ABSTRACT Home range sizes and spatial overlap of four sympatric squirrel species were investigated in a lowland dipterocarp forest in Malaysia using a radio-tracking method. The population density of Callosciurus caniceps was highest and C. notatus was next highest, while C. nigrovittatus and Lariscus insignis were scarce. C. caniceps was larger than C. nigrovittatus and C. notatus while L. insignis was extremely small. For females, home range size was smaller in L. insignis than Callosciurus spp., which may support the body weight hypothesis: larger species have larger home ranges. Among the three Callosciurus species, female C. caniceps had the smallest home range. These differences were accounted for by habitat characteristics rather than by density or body weight; C. caniceps was dominant in bushy areas and used crowded small trees while C. notatus and C. nigrovittatus used large trees in the forest. In this study, home range size did not change seasonally; this differs from studies in temperate regions, possibly because food availability is much less variable among seasons in tropical rain forest. Home range overlap among heterospecific individuals was common but different species seemed to partition space by using different vertical levels of the forest. Consequently, the home range size and spatial overlap of sympatric squirrel species may be affected by habitat diversity in tropical rain forest. [source] ADV measurements of velocity distributions in a gravel-bed flumeEARTH SURFACE PROCESSES AND LANDFORMS, Issue 7 2003Vito Ferro Abstract Velocity measurements carried out by an acoustic doppler velocimeter (ADV) in a rectangular laboratory ,ume having a gravel bed are presented. The velocity pro,les are measured in six verticals of the channel cross-section having an increasing distance (from 4 to 38·5 cm) from the ,ume wall. The experimental runs are carried out for ,ve different bed arrangements, characterized by different concentrations of coarser elements, and for the two conditions of small- and large-scale roughness. For both hydraulic conditions, the velocity measurements are ,rst used to test the applicability of the Dean pro,le and of the logarithmic pro,le corrected by a divergence function proposed in this paper. Then, for each value of the depth sediment ratio h/d84, the non-dimensional friction factor parameter is calculated by integration of the measured velocity distributions in the different verticals of the cross-section. Finally a semi-logarithmic ,ow resistance equation is empirically deduced. Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||