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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

A numerical investigation of the effect of induced porosity on the electromechanical switching of ferroelectric ceramics

Brown, Morgan, January 2005 (has links) (PDF)
Thesis (M.S. in mechanical engineering)--Washington State University, December 2005. / Includes bibliographical references (p. 32-33).
42

Influence of subsurface drainage and subirrigation practices on soil drainable porosity

Gao, Yuncai January 1990 (has links)
Subsurface drainage affects water table fluctuation patterns by removing the excess water from the soil. The annual average water table depths of the drained (A) and undrained (D) regimes are 0.83 and 0.48 m from the soil surface respectively. Subirrigation continuously provides water to the upper soil by capillary rise. The annual water table depths of the subirrigated regimes (B and C) are 0.61 and 0.70 m respectively. It is found that there is a significant curvilinear correlationship between the drainage flow rate and the water table height above the drain. Soil drainable porosity of different regimes was investigated by using the soil water balance approach. The average drainable porosity of regimes A and B are 6.0% and 4.9% from water table rise, and 5.9% and 4.5% from water table drawdown , respectively. Subirrigation adversely affects the soil drainable porosity. Soil drainable porosity is often considered as a constant. However, the results of this study indicate that it varies with the water table height above the drain. In the case of water table drawdown, this dependence can be successfully expressed by a negative exponential equation. In the case of water table rise, the correlation is not as significant, but there is still a trend that the drainable porosity decreases with the increase of the water table height above the drain. Evapotranspiration (ET) is often neglected in soil water balance models for the drain-able porosity determination. This may result in some errors. In this study, the potential ET rate was computed by the Penman and Hargreaves methods. These two methods give very similar ET values for the studied area. It is assumed that actual ET equals to the potential ET rate when the ground water table is close to the soil surface. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
43

A new chromatographic method for estimating parameters for microporous adsorbents /

Oberoi, Agyapal S. January 1979 (has links)
No description available.
44

Flow through a packed bed

Mujumdar, A. S. January 1968 (has links)
No description available.
45

Characteristics of turbulent flow through a packed bed.

Van der Merwe, David Frederick. January 1968 (has links)
No description available.
46

Mechanism and analysis of multiphase flow through soil

Elmonayeri, Diaa S. (Diaa Salah), 1950- January 1983 (has links)
No description available.
47

Primary and secondary porosity in sandcast aluminum-silicon alloys

Dimayuga, Francisco Cruz, II. January 1981 (has links)
No description available.
48

Simulation of microporosity in aluminum plate castings

Escobar de Obaldia, Enrique R 05 May 2007 (has links)
Porosity is known to be one of the primary factors controlling fatigue life and total elongation in cast aluminum components. The thrust of this study is to examine pore nucleation and growth effects for predicting gas microporosity in A356 plates. In this work, a solidification model is used to quantify and evaluate the discrepancy between experimental data and porosity calculated with different approaches. The first approach considers hydrogen supersaturation based on the transport of dissolved hydrogen and Sievert?s law. The second approach uses the hydrogen supersaturation calculated in the first approach combined with a local solidification time. The third approach considers a new hydrogen technique based on the transport of inclusions through the liquid metal and mushy zone. Computer simulations were performed modeling aluminum plate castings.
49

Axial mixing of liquids in porous media utilizing frequency response techniques /

Stahel, Edward Paul January 1962 (has links)
No description available.
50

Transport of adsorbable gas through microporous media /

Hazlebeck, David Eppler January 1964 (has links)
No description available.

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