Solid waste (SW) from a biodiesel plant has been successfully used for the removal of the hazardous cationic water soluble dye methylene blue (MB) from an aqueous phase. Batch adsorption studies were carried out by monitoring the pH, amount of adsorbent, initial dye concentration and contact time. Attempts have also been made to monitor the adsorption process through Langmuir, Freundlich, Temki...

Chemical modifications of clay to remove methylene blue (MB) from aqueous solutions at room temperature were compared. Natural bentonite (NC) was modified by cation exchange with hexadecyltrimethylammonium chloride (HC), bencyltriethylammonium chloride (BC), and tetramethylammonium chloride (TC) to reverse the surface polarity of the hydrophilic bentonite. The adsorption of MB was studied and f...

Water pollution caused by the lead(II) from the spent liquor has caught much attention. The research from the theoretical model to application fundaments is of vital importance. In this study, lead(II) adsorption isotherms are investigated using a series of hybrid membranes containing mercapto groups (-SH groups) as the hybrid adsorbents. To determine the best fitting equation, the experimental...

In this paper, an iterative method based on the transfer matrix approach was developed for evaluating sound speed and attenuation constant of air. If the air inside the impedance tube is treated as the tested material, such as porous materials, the transfer matrix approach can be easily used to identify the air’s acoustic properties. Then an iterative method can be applied in the post-processin...

Cameron and Erdős [6] asked whether the number of maximal sum-free sets in {1, . . . , n} is much smaller than the number of sum-free sets. In the same paper they gave a lower bound of 2bn/4c for the number of maximal sum-free sets. Here, we prove the following: For each 1 ≤ i ≤ 4, there is a constant Ci such that, given any n ≡ i mod 4, {1, . . . , n} contains (Ci + o(1))2 n/4 maximal sum-free...

The role of FTIR speetroscopy in catalytic studies is briefly discussed and some typical examples are shown. IR spectra of weakly bound hydrogen on PtjSi02 reveal surface heterogeneity; The hydrogen concentration on the surface is described by a Temkin isotherm. Adsorption of unsaturated C6 ring compounds on hydrogen poor PtjSi02 is essentially a self'-hydrogenation process resulting in the for...

In this paper, the ability of coconut bunch waste (CBW), an agricultural waste available in large quantity in Malaysia, to remove basic dye (methylene blue) from aqueous solution by adsorption was studied. Batch mode experiments were conducted at 30 degrees C to study the effects of pH and initial concentration of methylene blue (MB). Equilibrium adsorption isotherms and kinetics were investiga...

A detailed experimental study is presented of a 1 MW, 170 GHz gyrotron oscillator whose design is consistent with the ECH requirements of the International Thermonuclear Experimental Reactor (ITER) for bulk heating and current drive. This work is the first to demonstrate that megawatt power level at 170 GHz can be achieved in a gyrotron with high efficiency for plasma heating applications. Maxi...

The theory, design and experimental results of a wideband 140 GHz, 1 kW pulsed gyro-traveling wave amplifier are presented. The gyro-TWA operates in the HE(0,6) mode of a novel cylindrical confocal waveguide using a gyrating electron beam. The electromagnetic theory, interaction theory, design processes and experimental procedures have been described in detail. The experiment has produced over ...