Abstract:

This study investigated the potential use of olive pomace (OP) as an adsorbent to

reduce the concentration of methyl orange (MO) in aqueous solutions. The effect of

some important parameters on the process of adsorption was examined, including

pH, adsorbent weight, temperature, contact time, agitation speed, and the initial

concentration of MO. The results showed that the optimum concentration of MO was

10 ppm and the optimum pH = 2, indicating that the process of MO adsorption on the

surface of the OP was better in acidic medium. The equilibrium time was 80 min at a

speed of 100 rpm. The results of the study showed the significant role of OP weight,

agitation speed, temperature and the contact time in increasing the adsorption

efficiency. On comparing the pseudo first order and pseudo second order models, the

results showed that the pseudo second order model fitted the experimental data well.

The study also included testing of Langmuir and Freundlich models on the

adsorption isotherm data, and it was found that experimental data obey the

Freundlich isotherm. To sum up, the study showed that OP has high adsorption

efficiency to remove MO by applying a simple, inexpensive method.

This study investigate the removal efficiency of chromium (VI) from water by using (R-AgCl) Silver chloride resin (SCR) as selective sorbent material for removal chromium (VI) from aqueous solution; the study was carried out by sorption batch experiments at room temperature(25°C). Efficiency of Cr(VI) removal was determined by measuring the chromium concentration before and after the sorption process. Atomic absorption spectroscopy (AAS) method has been applied as analytical method for determination of Cr concentration in water. Governing factors for removal efficiency were proposed, analyzed and compared. It was conducted that the process is mostly affected by pH value of solution, mass of sorbent and concentration of Cr(VI) , which was the most efficient sorbent showed maximal efficiency and maximal sorption capacity, 1.5g of SCR after 60 min at 25 °C and pH 6.5 recovered 98% of Cr(VI) from 100 mL of water polluted with 20 mg of Cr(VI).

Abstract- Many methods have been applied in order to reduce nitrate concentration in aqueous solutions, among them

is the adsorption onto the surface of agricultural wastes. In this study, batch experiments were carried out to investigate

the adsorption of nitrate onto olive pomace (OP), a solid by-product of olive oil industry. To achieve this, six parameters

were studied by varying only one parameter at a time. These parameters were the effect of: pH, contact time,

temperature, adsorbent weight, agitation speed and nitrate concentration. The optimum pH was found to be 5, while the

optimum time was 75 minutes. Nitrate removal percentage was found to increase with increasing adsorbent weight or

temperature, with 92.5% of nitrate removed by using 2 g of OP and 48% of nitrate was removed at 60ºC. Generally,

agitation speed increased the nitrate removal percentage, while high initial concentration of nitrate was found to decrease

its removal percentage. These findings, combined with the low cost of OP and its abundance, suggest that OP is a

potential adsorbent for nitrate removal provided that the optimum conditions are applied. Applying this method for

nitrate removal will make drinking water safer to drink and wastewater safer to discharge.

A convenient method of preparing ultrafine polystyrene latex nano-particles with amino groups on the surface is developed. polystyrene latexes in the size range 50–400 nm were prepared via emulsion polymerization, using sodium dodecyl sulfate (SDS) as surfactant. The poly styrene with amino groups on the surface will be fine to use as organic filler to modify rubber. Transmission electron microscopy (TEM) was used to observe the morphology of silicon dioxide and functionalized polystyrene nanoparticles. The nature of bonding between the polymer and the reactive groups on the filler surfaces was analyzed using Fourier transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) was employed to examine the filler surface.  

Luotonins and its derivatives (Isoluotonins) are alkaloids from the aerial parts of Peganum nigellastrum Bunge. that display three major skeleton types. Luotonins A, B, and E are pyrroloquinazolinoquinoline alkaloids,. A few methods were known for the sysnthesis of Isoluotonin All luotonins have shown promising cytotoxicities towards selected human cancer cell lines, especially against leukemia P-388 cells. Luotonin A is the most active one, with its activity stemming from topoisomerase I-dependent DNAcleavage. Such intriguing biological activities and unique structures have led not only to the development of synthetic methods for the efficient synthesis of these compounds, but also to interest in structural modifications for improving the biological properties. Recent progress in the study of luotonins is covered. 

Brominated butyl rubber (BIIR) was crosslinked through an esterification reaction using the sodium salt of dicyclopentadiene dicarboxylic acid (DCPDCA) as crosslinking agent. The crosslinked BIIR could de-crosslink upon heating and re-crosslink upon cooling due to Diels-Alder type reversible de-dimerization/re-dimerization of dicyclopentadiene moieties in the rubber networks. Torque measurement of the crosslinked rubber was conducted at various temperatures using a typical curemeter to investigate the thermo-reversibility. It was revealed that proper temperature for thermal processing of the crosslinked BIIR would be around 174 °C, at which the crosslinked polymer exhibits good flowability and is not too high to induce unexpected side reactions. The torque measurement was also carried out to investigate the efficiency of antioxidant on retarding the loss of the thermo-reversibility of the crosslinked polymer during heating-cooling cycles. It was found that addition of antioxidant 2246 [2,2′-methylenebis(6-tert-butyl-4-methylphenol)] into BIIR could significantly improve the thermo-reversibility of DCPDCA crosslinked BIIR. Torque measurement provides a convenient and sensitive method to understand the thermal behavior of reversible covalent crosslinked polymer.