Ayat Bozeya

Geranyl acetate emulsions: surfactant association structures and emulsion inversion.

Three emulsions of geranyl acetate (GA)-in-water (W) with identical GA/W ratios and varying surfactant (S), Laureth 4, a commercial C(12)EO (4) compound, fractions were investigated for nature and stability. The emulsions with up to 6% surfactant were W/O, as expected with respect to the solubility of the surfactant in the oil. At 10% surfactant, the aqueous phase became the continuous one and the apparent stability of the emulsion was significantly enhanced. Analysis of the phase diagram and experimental evidence showed the high water content emulsion to be a liquid crystal-in-water emulsion; a kind that did not change even at extreme O/W and LC/W ratios.

Spontaneous Emulsification and Phase Equilibria in the System Water, Ethanol, and Benzene

A layer of a water/ethanol/benzene solution, with a composition close to the plait point in the system water/benzene/ethanol, was slowly applied on top of a layer of water of the same dimension avoiding mixing. Immediate spontaneous emulsification was observed in both phases, but most extensively in the aqueous phase. The increase in aqueous phase volume during this initial emulsification stage was significantly less than that, which occurred during a second stage lasting several days of individual transfer of compounds between the layers, with little additional emulsification, The calculated diffusion path for the initial stage of this experiment was consistent with the observation of the emulsification and provided insight on the relative magnitudes of fluxes and the directions of transport of each compound in each phase.

Spontaneous emulsification between incompatible aqueous solutions in the water/ethanol/benzene system.

Two aqueous solutions on the de-mixing line in the water/benzene/ethanol system formed an O/W emulsion, when mixed. Contacting the solutions without mixing gave a slow spontaneous emulsification over several hours. The emulsion in question was found exclusively in the solution of greater water fraction and the dimension of the emulsion layer expanded as the square root of time. The reduction in the volume fraction the solution with less water was divided by the volume fraction of the emulsion, giving an - albeit exaggerated - measure of the volume fraction of the dispersed phase in the emulsion. It reached 0.6 after 1h, after which it remained constant for 3h. The composition change from the initial stage to the final equilibrium was calculated using a combination of the phase diagram features and earlier diffusion flux calculations in a similar system to estimate the fraction of the compounds transferred between the layers. These transfers were unexpectedly clear-cut, 95 wt% of the water in the less water solution was transferred into the water rich solution as was 80% of the ethanol. In the same manner 95% of the benzene in the water rich solution was relocated into the water poor solution.

Adsorption of Pb(II) on raw and organically modified Jordanian bentonite

Abstract A comparative study using bentonite (BT), hexadecyltrimethylammonium-modified bentonite (BT-HDTMA) and phenyl fatty hydroxamic acid-modified bentonite (BT-PFHA) as adsorbents for the removal of Pb(II) has been proposed. These adsorbents were characterized by X-ray diffraction, X-ray fluorescence, Fourier-transform infrared spectroscopy and surface area measurement. Cation exchange capacity was also determined in this study. The adsorbent capabilities for Pb(II) from aqueous solution were investigated, and the optimal experimental conditions including adsorption time, adsorbent dosage, the initial concentration of Pb(II), pH and temperature that might influence the adsorption performance were also investigated. The experimental equilibrium adsorption data were tested by four widely used two-parameter equations, the Langmuir, Freundlich, Dubinin- Radushkevich (D-R) and Temkin isotherms. The monolayer adsorption capacities of BT, BT-HDTMA and BT-PFHA for Pb(II) were 149.3, 227.3 and 256.4 mg/g, respectively. The experimental kinetic data were analysed by pseudo-first order, pseudo-second order and intraparticle diffusion kinetics models. The experimental data fitted very well with the pseudo-second order kinetic model. Determination of the thermodynamic parameters, ΔG, ΔH and ΔS showed the adsorption to be feasible, spontaneous and exothermic.

Some experiments on complex spontaneous emulsification in the system water–benzene–ethanol

The system water–benzene–ethanol was used to illustrate the complexity of spontaneous emulsification, when water-poor emulsions are brought in contact with water. In the first case, an O/W emulsion located close to the plait point in the system was used. The aqueous phase in the emulsion was incompatible with water, and a strong spontaneous emulsification to an O/W between the two liquids took place in the water layer close to the interface between layers. In the second case, a W/O emulsion, also close to the plait point, was brought in contact with water. Now, the spontaneous emulsification between the water and the oil phase of the original emulsion to an O/W emulsion also took place in the water layer forming a distinct emulsion layer beneath the interface.

Jordan Conservation of Cultural Heritage in ERA

The Jordan Conservation of Cultural Heritage in ERA - JOCHERA project is aiming at overall reinforcement of University of Jordan (UJ), Hamdi Mango Center for Scientific Research (HMCSR) in Jordan cooperation capacities for cultural heritage protection research in the context of the European Research Area and development to the Conservation centre of excellence to respond to Jordans socio-economic needs. The JOCHERA impact will be increased capacities of the UJ in terms of (i) better research and innovation management, (ii) improved international Science & Technology cooperation and participation in FP7, (iii) enhanced cultural heritage protection research capacities, and (v) defined strategic development framework in order to increase UJ visibility and scope. Likewise, JOCHERA will increase research and innovation linkages within Jordan in particular with SMEs, enable better opportunities to young researchers and enhance EU-JO RTD cooperation landscape. The project duration is 24 months, started in 1st D...

Assessment of Some Heavy Metals in the Dead Sea Mud and Treatment Optimization

ABSTRACT This paper describes the experimental remediation of the Dead Sea mud and the quantitative determination of some heavy metals. Herein, two chelating agents were employed as extracting aqueous solution: ethylenediaminetetraacetic acid (EDTA) and citric acid. The study focused on the main known heavy metals that were reported previously to be in the Dead Sea mud, which are Co, Ni, Pb, Zn, and Cr. Findings had indicated that citric acid was efficient in the removal of the aforementioned heavy metals. Physicochemical parameters that were expected to affect the removal of metals in the Dead Sea mud were optimized. Those parameters were the chelating agent concentration, mixing time and speed, type of washing water, temperature, and pH. The results showed that the best removal of heavy metals from Dead Sea mud can be achieved under optimum citric acid concentration, 1.5 g/50 mL for treatment of 10 g mud. Optimum mixing speed and time were found to be 800 rpm and 1 hr, respectively. Regarding washing water, it was found that the use of the same water for repeated washing provided better removal percentages. pH values and temperature had effect on removal percentages of the heavy metals from mud. However, working at pH 7 and room temperature would provide convenient results for heavy metal removal.

Fungicidal and nematicidal activities for essential oils formulated in Janus emulsion

ABSTRACT This study investigated the nematicidal and fungicidal activities of the two immiscible camphor and orange oils formulated in Janus emulsion (JE). JE was prepared from camphor and orange oils by a single-step emulsification with different concentrations chosen from an established phase diagram. Camphor oil nematicidal activity was studied against the root knot nematode Meloidogyne incognita, while orange oil fungicidal activity was studied against the wilt fungus Fusarium oxysporum f. sp. lycopersici (Fol). For a comparison study, different concentrations of JE and double emulsions were prepared. Results showed that JE had a significant mortality effect on the second-stage juveniles (J2s) M. incognita with 81% mortality and was able to delay the growth of Fol four and seven days after exposure, while changes in the efficiency of DE were recorded. Prepared JEs were shown to maintain the efficiency and to have slow release profiles for encapsulated oils. GRAPHICAL ABSTRACT