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The most challenging aspect in petroleum industry is high produced water accompanying crude oil extraction. In modern days, environmental attention has become very significant due to large quantity of produced water. Produced water in crude oil extraction consists of a mixture of several compounds, including inorganic, organic and other elements. The elements in produced water have a wide environmental influence and sometimes cause poisonous impact on sounded area. Meanwhile, there are several techniques to treat produced water. However, a major part of produced water is an emulsion and this leads to a major problem associated with crude oil treatment and transport. At the same time, limitations in treatment techniques for produced water have been demanding researchers to investigate on demulsification techniques for several years. Researchers also noted that there are a lot of elements influencing emulsion stability and interfacial film, including asphaltenes, resins, solid particles, water and oil content, PH, etc. However, one of the techniques that has received attention in enhanced oil recovery is a chemical method by using surface active agents (surfactant). Keywords: Emulsion, Produced water, Interfacial stability, Demulsification mechanism, Surfactant

Latex production from Hevea brasiliensis rubber tree is the second most important commodity in Malaysia, but this industry is threatened by the white root rot disease (WRD) caused by Rigidoporus microporus that leads to considerable latex yield loss and tree death. This study aimed to characterize and compare the virulence of five R. microporus isolates obtained from infected rubber trees located at different states in Malaysia. These isolates were subjected to morphological and molecular characterization for species confirmation and pathogenicity test for the determination of virulence level. BLAST search showed that the ITS sequences of all the pathogen isolates were 99% identical to R. microporus isolate SEG (accession number: MG199553) from Malaysia. The pathogenicity test of R. microporus isolates conducted in a nursery with 24 seedlings per isolate showed that isolate RL21 from Sarawak has developed the most severe above- and below-ground symptoms of WRD on the rubber clone RRIM600 as host. Six months after being infected with R. microporus, RL21 was evaluated with the highest average of disease severity index of 80.52% for above- and below-ground symptoms, followed by RL22 (68.65%), RL20 (66.04%), RL26 (54.38%), and RL25 (43.13%). The in vitro growth condition tests showed that isolate RL21 of R. microporus has optimum growth at 25–30 °C, with the preference of weakly acidic to neutral environments (pH 6–7). This study revealed that different virulence levels are possessed among different R. microporus isolates even though they were isolated from the same host species under the same climate region. Taken together, field evaluation through visual observation and laboratory assays have led to screening of the most virulent isolate. Determination of the most virulent isolate in the present study is vital and shall be taken into consideration for the selection of suitable pathogen isolate in the development of more effective control measures in combating tenacious R. microporus.

Electric Arc Furnace steel slag (EAFS) is the waste produced in steelmaking industry. Environmental problem such as pollution will occur when dumping the steel slag waste into the landfill. These steel slags have properties that are suitable for various applications such as water treatment and wastewater. The objective of this study is to develop efficient and economical chlorination route for EAFS extraction by using leaching process. Various parameters such as concentration of hydrochloric acid, particle size of steel slag, reaction time and reaction temperature are investigated to determine the optimum conditions. As a result, the dissolution rate can be determined by changing the parameters, such as concentration of hydrochloric acid, particle size of steel slag, reaction time and reaction temperature. The optimum conditions for dissolution rates for the leaching process is at 3.0 M hydrochloric acid, particle size of 1.18 mm, reaction time of 2.5 hour and the temperature of 90°C.

The application of solar drying (SD) and heat pump-assisted solar drying (HPSD) on the retention of flavonoid components, total color changes, and water activity ofClinacanthus nutansLindau leaves were investigated. Analysis of data shows significantly higher extractable yield and flavonoid (orientin and vitexin) percentage during the drying with HPSD. The same drying technique also revealed optimum color values and low water activity. Thin-layer models fitted to the experimental data show that Hii and Law model is suitable for SD, while logarithmic model is able to give a good fit to HPSD. [ABSTRACT FROM AUTHOR]

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Extensive employment of biomaterials in the areas of biomedical and microbiological applications is considered to be of prime importance. As expected, oil based polymer materials were gradually replaced by natural or synthetic biopolymers due to their well-known intrinsic characteristics such as biodegradability, non-toxicity and biocompatibility. Literature on this subject was found to be expanding, especially in the areas of biomedical and microbiological applications. Introduction of porosity into a biomaterial broadens the scope of applications. In addition, increased porosity can have a beneficial effect for the applications which exploit their exceptional ability of loading, retaining and releasing of fluids. Different applications require a unique set of pore characteristics in the biopolymer matrix. Various pore morphologies have different characteristics and contribute different performances to the biopolymer matrix. Fabrication methods for bio-based porous materials more related to the choice of material. By choosing the appropriate combination of fabrication technique and biomaterial employment, one can obtain tunable pore characteristic to fulfill the requirements of desired application. In our previous review, we described the literature related to biopolymers and fabrication techniques of porous materials. This paper we will focus on the biomedical and microbiological applications of bio-based porous materials. [ABSTRACT FROM AUTHOR]

Blends of ethylene vinyl acetate (EVA) copolymer and recycled nitrile rubber (rNBR) were prepared using an internal mixer. N,N'-m-phenylenedimaleimide (HVA-2) was added into the blend composed of 70 wt % of EVA and 30 wt % of rNBR, and served as a crosslinking agent. The HVA-2 concentration was varied from 0 to 5 phr. The changes in the compatibility of the blends were investigated before and after electron beam irradiation by means of physical and morphological tests. The results obtained from these tests were then analysed, namely tensile strength (TS), modulus 100 (M100), elongation at break, gel content and scanning electron microscopy (SEM). The results showed that the TS and elongation at break had decreased with increasing in HVA-2 concentration and electron beam irradiation dose, while the M100 had increased. It is believed that the blends had undergone early crosslinking reaction during mixing. Hence, the brittleness of the materials had increased upon exposure to electron beam irradiation due to the excessive crosslinking bonds. This observation was supported by the gel content and SEM micrographs. [ABSTRACT FROM AUTHOR]

Redox polymerization of poly(acrylonitrile-co-acrylic acid) (poly(AN-co-AA)) is performed at 40 °C under N2 gas by varying the ratio of acrylonitrile (AN) and acrylic acid (AA) in the feed. The yield production of poly(acrylonitrile) (PAN) is 73% and poly(AN-co-AA) with a feed ratio of 93:7 is the highest yield (72%). The PAN and poly(AN-co-AA) are further chemically modify with hydroxylamine hydrochloride. The FTIR spectroscopy is used to confirm the copolymerization of poly(AN-co-AA) and chemical modification of poly(AN-co-AA). Elemental microanalysis shows that the overall trend percentage of carbon, hydrogen, and nitrogen for all feed ratios are slightly decreasing as the feed ratio of AA is increasing except for poly(AN-co-AA) 93:7. The SEM images shows that spherical diameter of poly(AN-co-AA) is smaller compared to the PAN and amidoxime (AO) modified poly(AN-co-AA). The TGA (thermogravimetric analysis) analysis reveals that the poly(AN-co-AA) degrades at lower temperatures compared to the PAN but higher than AO modified poly(AN-co-AA). The case study adsorption test showed that the AO modified poly(AN-co-AA) 93:7 had the highest percentage removal of Cd2+ and Pb2+. [ABSTRACT FROM AUTHOR]

ABSTRACT Scrap rubber reclamation is one of the most desirable approaches to solve the disposal problem of used tires. However, reclaimed tire rubber (RTR) has not gained enough attention due to its poor properties. In this work, the effects of poly(ethylene- co-vinyl acetate) (EVA) addition and electron beam (EB) irradiation on the properties of RTR were studied. The RTR/EVA blends containing 100-0 wt % of RTR were prepared in the internal mixer followed by EB irradiation with doses ranging from 50 to 200 kGy. The RTR/EVA blends were subjected to mechanical, gel content, thermal, and morphological analysis. It was found that the addition of EVA to RTR improved the mechanical properties of RTR. However, results revealed that RTR undergoes irradiation-induced crosslinking in a relatively lesser extent as compared to EVA. This observation is associated with the stabilization and radical scavenging effects of additives, which are present in the RTR matrix. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41649. [ABSTRACT FROM AUTHOR]

Rheology is the science of deformation and flow behavior of fluid. Knowledge of rheological properties of fluid foods and their variation with temperature and concentration have been globally important for industrialization of food technology for quality, understanding the texture, process engineering application, correlation with sensory evaluation, designing of transport system , equipment design (heat exchanger and evaporator ), deciding pump capacity and power requirement for mixing. The aim of this study was to determine the rheological behavior of pomelo juice at different concentrations (20-60.4%) and temperatures (23-60°C) by using a rotational rotational Haake Rheostress 600 rheometer. Pomelo juice was found to exhibit both Newtonian and Non-Newtonian behavior. For lower concentration the Newtonian behavior is observed while at higher concentration Non-Newtonian behavior was observed. Standard error (SE) method was selected on the basis to carry out the error analysis due to the best fit model. For the four models the values of SE show that the Herschel-Bulkley and Power Law models perform better than the Bingham and Casson models but Herschel- Bulkley model is true at higher concentration. The rheological model of pomelo juice, incorporating the effects of concentration and temperature was developed. The master-curve was investigated for comparing data from different products at a reference temperature of 40°C. Multiple regression analysis indicated Master-Curve presents good agreement for pomelo juice at all concentrations studied with R2>0.8. [ABSTRACT FROM AUTHOR]

Low-density polyethylene (LDPE) nanocomposites with alumina as filler were prepared by melt intercalation process by using Haake Rheomix at 125°C for 12 min followed by compression moulding. Prior to blending of the alumina with LDPE, alumina particles were dispersed by using ultrasonication process. Surfactant was used to modify the alumina surface in order to enhance the interaction between alumina and LDPE. The melting temperature and crystallinity of nanocomposites were investigated by differential scanning calorimetry (DSC). Studies on dynamic mechanical analysis (DMA) were made to follow the changes in dynamic mechanical properties upon addition of nanoalumina to LDPE. Thermal stability of the nanocomposites was studied by using thermal gravimetric analysis (TGA). It was found that the crystallinity and melting temperature of LDPE/alumina decreased with the increase in alumina content. The results on TGA and DMA analysis revealed that the thermal stability of LDPE improved with the addition of alumina particle. [ABSTRACT FROM PUBLISHER]

The effect of irradiation on a 90/10 ethylene vinyl acetate/waste tire dust (EVA/WTD) blend was studied in the presence of 4 phr trimethylolpropane triacrylate (TMPTA) or tripropyleneglycol diacrylate (TPGDA). The blend was irradiated using a 3.0-MeV electron beam machine at 0, 50, 100, 150, and 200 kGy irradiation doses. The properties studied include gel content, tensile properties, hardness, morphology, and dynamic mechanical properties. The result revealed that the increment in irradiation doses will increase the percentage of gel content. The gel content further increased with the introduction of TMPTA and TPGDA. This is attributed to the increase in crosslink density. Tensile properties of EVA/WTD blend increase with the introduction of irradiation except for elongation at break. The tensile-fractured surface of EVA/WTD blends showed ductile type of failure upon irradiation of the blends in the presence of crosslinking agent. One glass transition temperature obtained from dynamic mechanical analysis for 90/10 EVA/WTD blend after irradiation indicates that compatibility between EVA and WTD phases increased. [ABSTRACT FROM PUBLISHER]

Crude palm oil (CPO) is a renewable bio-based resource. It is an attractive alternative fuel which provides the potential to reduce emission problems. CPO is an example of biofuels that can be blended with petroleum distillates as a fuel in mobile engines and industrial processes to help offset the increasing energy demand This paper highlights the results of blended Crude palm oil (CPO)/Medium fuel oil (MFO) as an alternative environmentally friendly boiler's fuel. Physical properties and heating values of the blended fuels been presented Emission test of a blend containing 50% CPO in MFO fuel was also examined using a commercial boiler had been conducted in a local oil palm mill in Malaysia. The blend burned satisfactorily without major modification to the appliance and fuel delivery system. Emission of SO2, H2S and NOx were very much reduced as compared to the combustion of MFO. Results indicate potential replacement for the petroleum distillates with this blend. [ABSTRACT FROM AUTHOR]