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1
Content available remote Termofizyczne właściwości kompozytów Ag-C
PL
Praca prezentuje wyniki wstępnych badań materiałów typu Ag-C, otrzymanych metodą metalurgii proszków, domieszkowanych różnymi postaciami węgla (nanoproszek węgla, nanorurki węglowe oraz tlenek grafenu). Na podstawie, przeprowadzonych metodami skaningo- wej mikroskopii elektronowej, badań mikrostrukturalnych oraz wykonanych badań właściwości termofizycznych metodami DSC, DIL i LFA stwierdzono, że zastosowana procedura wytwarzania materiałów kompozytowych nie zapewnia zadawalającego rozmieszczenia fazy węglowej w osnowie metalowej. W celu uzyskania poprawy jednorodności materiałów typu Ag-C należy opracować sposób deaglomeracji fazy węglowej.
EN
The work presents the results of preliminary studies of Ag-C type materials obtained by the powder metallurgy method and doped by using carbon of different form, comprising carbon nanopowder, carbon nanotubes, and graphene oxide. Basing on SEM microstructural studies and DSC, DIL, and LFA measurements, it has been stated that the applied manufacturing procedure did not guarantee the satisfied distribution of the carbon phase within the metal matrix. A deagglomeration method of the carbon phase is to be developed to improve homogeneity of the Ag-C materials.
EN
The paper presents basic hydrological processes of rainfall-runoff transformation in experimental watershed of the Trzebuńka stream. Several field experiments were made to determine basic hydrological parameters, The influence of atmospheric circulation on spatial distribution of precipitation was investigated. Attempt was made to determine the influence of forest vegetation, undergrowth, forest litter retention and surface retention on water loss in the catchment. Water retention capacity of soil was also estimated. Developed mathematical model of rainfall-runoff transformation was used in several simulations. This allowed evaluating the effect of atmospheric circulation and spatial rainfall distribution on water balance, the influence of vegetation cover with forest litter on water runoff and the effect of forest litter alone in a hypothetical scenario of forest cutting.
PL
W pracy przedstawiono podstawowe procesy hydrologiczne, biorące udziałw transformacji opadu w odpływ w zlewni badawczej potoku Trzebuńka. W celu określenia podstawowych parametrów hydrologicznych na terenie zlewni tego potoku przeprowadzono badania terenowe. Między innymi podjęto próbę ustalenia wpływu cyrkulacji atmosfery na przestrzenny rozkład opadu, określono wpływ roślinności leśnej, upraw niskich oraz retencji ściółki i retencji powierzchni terenu na ilość strat wody w zlewni. Określone zostały również wielkości retencji wody w glebie. Opracowany matematyczny model transformacji opadu w odpływ o parametrach rozłożonych został wykorzystany do przeprowadzenia różnych symulacji. Między innymi posłużył do oceny wpływu: cyrkulacji atmosferycznej i przestrzennego rozkładu opadu na ogólny bilans zlewni; pokrywy roślinnej wraz z retencją ściółki leśnej na kształtowanie odpływu ze zlewni oraz retencji samej ściółki - scenariusz hipotetyczny, który może zaistnieć w przypadku wycięcia lasu.
EN
The paper presents a description of retention reservoir and the process of rainfall water storage in forest floor as a function of time. It required investigation of reservoir filling in different conditions of active experiment. Laboratory conditions were the simplest to perform and allowed determination of retention in relation to water content in forest floor before sprinkling, i.e. to the initial retention. Maximum forest floor retention capability was also evaluated. As an effect, formulas for maximum and current capacity evaluation are presented and the process of water retention in any kind of forest floor is described. Basic forest floor feature i.e. dry forest litter mass per area unit (g·cm-²) is needed to determine its retention capabilities.
PL
Prezentowane w pracy miały za cel rozpoznanie właściwości retencyjnych ściółki leśnej oraz określenie sposobów oceny tych właściwości. U podstaw realizacji tej pracy przyjęto założenia dotyczące określenia poszukiwanych wartości, zależności od wybranych cech fizycznych ściółki leśnej, które stosunkowo łatwo można byłoby ustalić poprzez wykonanie prostych pomiarów. Jednym z podstawowych celów badań było podanie sposobu określenia zdolności maksymalnej, bieżącej oraz przebiegu procesu retencji wody przez dowolną ściółkę leśną. Badania laboratoryjne obejmowały określenie: maksymalnej pojemności ściółki leśnej jako zbiornika retencyjnego oraz jej podzbiorników, tj. wody wolnej i wody zwilżającej, w zależności od wartości suchej masy ściółki leśnej przypadającej na jednostkę powierzchni terenu (1 cm²); sposobu napełniania zbiornika i opisu tego procesu poprzez podanie równań regresyjnych napełniania zbiornika wody wolnej i wody zwilżającej łącznie, decydujących o całkowitym zatrzymaniu wody w ściółce leśnej. Procesy te uzależniono od retencji maksymalnej zbiorników składowych, od natężenia zraszania i od retencji początkowej.
4
Content available remote Zbiornik intercepcyjny brzozy brodawkowej (Betula pendula Roth)
EN
The aim of the paper is the description of the tree interception reservoir which, in this case, is the reservoir of European white birch (Betula pendula Roth). The target is to determine the interception capacity of an arbitrary species tree. A method is sought for determining the interception capacity of the reservoir of a tree which retains on its surface, in its structure, certain amounts of rain water passing from the atmosphere to the ground surface here the plant lives. To give the sought reservoir the physical sense, the reservoir base was accepted as the tree surface (two-side leaf area plus bark area), while the reservoir height was defined as the average depth of water layer that can be retained on the surface. The measured leaf area and bark area exhibit strong correlation with the breast height diameter and tree shoot diameter. It is therefore possible to determine the tree leaf and bark area based on the measured breast height diameter and tree height.Experimentally determined average depth of water layer on tree green and bark surfaces enables the tree interception reservoir height to be determined. Due to this, after making inventory of trees on the representative plot of the forest area, and taking into account its age and compactness, there will be the possibility to calculate its interception capacity. In this paper a method of calculating of the interception reservoir capacity of European white birch occurring frequently as single species or as an addition to other forest communities. As regards to its structure, the birch represents a specific tree type. Up today, in the Hydrology Section of the Institute of Water Engineering and Water Management of Cracow University of Technology, there were developed descriptions of interception reservoirs of other trees, both coniferous and deciduous, as spruce (Picea abies), oak (Quercus robur), hornbeam (Carpinus betulus), and pine (Pinus silvestris).We hope that the descriptions of reservoirs of various tree species will be integrated into a common description in future.
EN
Retention capabilities were described for different vegetation types. This description was used for evaluation of influence of vegetation retention capabilities on flood run-off formation in Trzebuńka stream catchment. Mathematical model of rainfall run-off transformation WISTOO was used. Based on results of analysis, can be stated that flood waves after forest cutting increase comparing to waves in actual forestation conditions. Those differences are minor for precipitation with p=50%. For smaller probability of high intensities rainfall occurrence, flood peak run-off value is higher. Forest cutting can result in twice or even higher increase of peak run-off. In case of different catchment aforestation (according "vertical" downstream or upstream and "linear" from catchment boundary or in other direction) and different forestation coefficient, the biggest effect for sale water run-off gives afforestation of upper parts of catchment which confirms state-of-the-art.Described in article calculation methods of vegetation influence on flood run-off enable quantitative evaluation of change of flood wave shape in specific catchment conditions and rainfall distribution. Developed methods enable quantitative description of delay and decrease of flood waves depending on forest management practices in catchment. Up to now vegetation was considered affecting run-off by taking part of precipitation and by run-off delay as effect of water retention in vegetation retention reservoir. It was not mentioned however that water retention by plants enables bigger outflow to deeper soil layers eliminating additional amount of water from fast surface and subsurface run-off decreasing this way volume of flood wave.
6
EN
The paper concerns the method of determining reservoir capacity of pine trees (Pinus silvestris) commonly occurring in Poland and Europe. Based on cumbersome and many-year measurements, experimental and field studies on plots in the Trzebuńka stream experimental catchment of the Hydrology Section of the Institute of Water Engineering and Water Management of Cracow University of Technology, a physical model is presented of the interception reservoir of an individual tree. The tree green (needle) surface and surface of stem and branches is the basis of the reservoir. Its height is determined by the depth of water layer that can be retained on the surface. However, if it can be accepted that the whole green surface retains rain water of the same average depth, then the depth of this layer on the bark surface depends on the stem or branch diameter. The older the stem or branch are the greater is the possibility of intercepting water because ofincreased roughness and fracturing of the intercepting surface. The magnitude of the green and bark surface of an arbitrary tree, as well as the depth of water intercepted by these surfaces, can be made using the relation with physical characteristics of the tree that are relatively easy to be measured: tree height, breast height diameter or both. If the green and total pine surface areas are to be calculated, the pine crown height may be added. It can be then calculated the green surface area of a tree taking into account the total surface area, not only the surface of the leaf projection onto the plane surface, FL1, (so FL2), stem surface, FB, and the bark total surface, FkC, as well as the depth of water stored on the bark surface Rk, versus the stem and branch diameter d. Water storage on the green surface was divided into wetting storage which will leave the surface by evaporation, and free water storage that gravity can force to flow down.All calculation formulas have high indices of correlation significance and enable the interception calculation to be carried out of a pine canopy consisting of trees of any age and density.
EN
Analysis of forest regulation role in the rainfall-runoff process originated field studies in the Stróża experimental catchments. The study was carried out during six consecutive years (1996-2001). The aim of the study was to determine the litter retention under natural conditions. The initial retention is understood as the water layer in litter at the moment the rainfall begins. The litter initial retention is a very important factor in further considerations concerning determination of the amount of water stored in the litter during rainfall, as well as in determining relationships among maximum retention, litter dry mass and initial retention. The greatest problem is to determine the litter initial retention as no such investigations were made. Six years of study resulted in the rich and diverse material enabling statistical analysis of litter initial retention relations with meteorological parameters to be made. Simultaneous meteorological observations made in the forest and at a meteorological station made it possible to take a decision to use standard meteorological measurement to determine indices related to initial retention. The first stage of the analysis was to determine relationships between the dry mass of the litter per unit area (g/cm2) and the antecedent rainfall index. The second of the analysis was to develop relationships between the initial retention,antecedent rainfall index, moving average temperature, moving average humidity deficit and the dry mass of the litter per unit area (g/cm2). To calculate the antecedent rainfall index, Pa, the Lambor formula was applied: [Pa=1/120 ...] As the basic meteorological parameters (rainfall, temperature, humidity, deficit, litter density and its height) were available, the following formula was developed: r0=14,473Pa0,217tśr0,167Δ-0,151δ0,936 where: r0 - initial retention; Pa - antecedent rainfall index; t - moving average temperature; Δ - moving average humidity deficit; δ - dry mass of the litter per unit area. With 1338 observations, the multiple correlation coefficient was 0,91, which makes determination of forest initioal litter retention possible.
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