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The study presented herein is a continuation of investigations on the choice of a Theological model that would best describe the real processes of soil deformation. The study was carried out for three soil samples of the granulometric compositions of a weakly loamy sand, a strongly loamy sand, and a light silty loam, using the triaxial consolidation test with no water filtration at a steady rate of deformation. Comparing the experimental characteristics with the solution of a non-linear equation of a standard model, the author determined the quantitatively variable coefficients of viscosity and elasticity.
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Procesy zniszczenia w komorkowym osrodku roslinnym

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Prezentowana praca przedstawia teoretyczny model zniszczenia materiału zbudowanego z komórek o elastycznej ścianie otaczającej wnętrze złożone z cieczy i gazu oraz metody eksperymentalne obserwacji i ilościowej analizy zmian parametrów struktury w czasie badanego procesu. Uzyskane wyniki pokazują, że zniszczenie w komórkowym materiale Roślinnym pod wpływem sił zewnętrznych ma charakter pęknięć i związane jest z rozerwaniem ścian komórkowych.
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W pracy przedstawiono badania prowadzone w Instytucie Agrofizyki PAN pod kierunkiem Profesora Janusza Hamana w wyniku współpracy z Wydziałem Techniki Rolniczej AR w Lublinie. Badania te zmierzają do sformułowania wspólnej mechaniki dla ośrodków biologicznych pochodzenia rolniczego.
Soil, as a tractive surface for agricultural tractors as well as military and off-road vehicles, is required to withstand dynamic loads occuring under wheels or tracks. mechanical properties of soil medium result in dependence between load, velocity of sytain and stress- deformation relationships. These information are of the major importance when considering soil compaction as well as tractive performaces of the vehicles. Having analyzed results pulished by many researches, the autors of this work haveconcluded the lack of a proper method for soil stress- deformation measurements. Therefore, the aim of the work is to desing and research some new methods of soil stress- deformation measurements. In the second chapter results of experimental research with a SST transducer are shown. The transducer allows to measure strasses for complete soil stress state calculations. Additionally, a mechanical system was used for soil deformations measurements in the three direction in space.The third chapter contains numerous details on desing of an improved version of the measuring system with an triaxal head. Soil deformations are measured with a novel method, which uses laser and a CCD camera.The next chapter describes another version, which is suitable for field experiments. Detailed descriptions of field procedures are given. A system for soil stress- deformation measurements developed with laser and optical fibers is shown in the last numbered chapter. There are also described some future designs, containing nanotechnology and telemetries.
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Agrophysics is a science dealing with physical properties and processes affecting plant production. The main topics of agrophysical investigations are mass ( water, air, plant nutrients) and energy (light, heat) exchange in the soil-plant-atmosphere continuum and way their regulation to reach biomass of high quantity and quality. Agrophisical investigations can be presented in the form of a tree - parameter system of classification. the term "Agrophysics" similarly to "Agrochemistry" "Agrobiology" "Agromelioration""Agroclimatology" or "Agroecology" has been fully accepted as an agricultural specialization. Agrophysics research are developed by meny scientific institutes but only the Instituí of Agrophysics in Lublin (Poland) is the strongest unit for a complex investigations in the field of agrophysics.AC The Institute of Agrophysics (IA PAN) is one of the institutes of the Polish Academy of Sciences, It was founded by Professor Bohdan Dobrzański in 1968 in Lublin who was the first and long-term director of the Institute (till 1980). The staff of the Institute consists of 100 workers including 68 scientific representing various specializations: physics, physicochemistry, soil science, agricultural engineering, mechanics, mathematics, electronics, geography and biology. These scientists have ery high qualifications achieved during long trainings in domestic and foreign centres. They were employed as postgraduate students and got their scientific degree on agrophysics. The Institute uses it's own building covering a surface of about 5 000 m2 situated in Lublin-Felin. The scientific structure of the Institute consists of six departments: 1. Hydrolherrnophysics of Soil Hnvironment and Agricultural Materials. 2. Aeration and Gas Exchange of Soil Environment and Agricultural Materials. 3. Mechanics of Agricultural Materials. 4. Physicochemistry of Agricultural Materials. 5. Agrophysical Bases of Soil Environment Management. 6. Physical Bases of the Evaluation and Improvement of Plant Materials, The Institute is a coordinator of agrophysical investigations in Poland and cooperates with meny scientific institutions over the world. The agrophysicial investigations carried out by the Institute and under its coordination allow us to deepen our fundamental knowledge about the physical and physicochemical properties and processes concerning agricultural materials. They also have introduced new elements to environmental protection which are significant to the economy. The results from these investigations may be used to: decrease soil physical degradation caused by erosion, soil crusting, sealing, compaction and structure destruction; increase the efficiency of water and fertilizer use; improve the technology of harvesting, storing and processing of plant materials to decrease quantitative ad qualitative losses of these materials; improve plant breading through formulation of physical properties of plants. The development of a theoretical basis in the field of agrophysics is of great importance for many agricultural specialization, e.g., soil science, soil technology, land reclamation, agricultural engineering, agroclimatology, agrochemistry, plant breeding and plant technology.
W wyniku odkształcania tkanki roślinnej zachodzą w niej nieodwracalne procesy fizyczne, prowadzą w konsekwencji do osiągnięcia stanu wytrzymałości. Jednym z tych nieodwracalnych procesów jest niszczenie struktury komórkowej, które zachodzi poprzez pękanie błon komórkowych oraz utratę spójności w warstwie pektynowych lamelli. W wyniku tych zjawisk emitowany jest sygnał emisji akustycznej. W pracy opisano metodę emisji akustycznej i jej zastosowanie do badań procesów pękania tkanek roślinnych.
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