No abstract

In this study, two different one-dimensional tests (only vertical flow) (pressure filtration test and suction filtration test) were compared to determine variability in the results due to different forms of pressure application. In addition, an innovative two-dimensional filtration apparatus (with both vertical and radial flow) was developed in order to determine the effect of radial flow on the results. This apparatus will more accurately imitate the real-life dewatering application of geotextile tubes. Unlike on-site ''hanging bag'' and ''pressurized geotextile dewatering'' tests, this laboratory apparatus was designed in a form that will facilitate the studying of dewatering rate vertically and radially separately. It will also be used by mathematicians, as its geometric form will be more conducive to the analysis of dewatering. This will aid in the creation of a simple and fast mathematical model to determine geotextile dewatering rate, which will reduce the need and cost of experimental testing during prior to actual dewatering in the site.

No abstract

Sr 4 Ru 2 O 9 has a P62C space group and differs from the Ruddelsden-Popper series of the strontium ruthenate family where Ru is distinctly present in Ru +5 state with no Jahn-Teller activity. A significant increase in magnetic moment and coercivity is observed along with lowering of resistivity, especially around a critical concentration of x = 0.2 in Sr 4−x La x Ru 2−x Mn x O 9 . Such an unusual effect is correlated to the mixed magnetic pair effect arising out from the variable oxidation states of Ru as suggested by x-ray photoelectron spectroscopic studies. pure oxides were mixed thoroughly according to the desired stoichiometric, calcined at 850°C for 36 h in the presence of O 2 atmosphere, and subsequently sintered under O 2 atmosphere at 950°C for 36 h. The homogeneity of the samples was checked with x-ray powder diffraction. Standard fourprobe techniques were employed to study the transport properties. Magnetization measurements were carried out using a vibrating-sample magnetometer ͑VSM͒ Oxford instrument.