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991.
Hopke PK Cohen DD Begum BA Biswas SK Ni B Pandit GG Santoso M Chung YS Rahman SA Hamzah MS Davy P Markwitz A Waheed S Siddique N Santos FL Pabroa PC Seneviratne MC Wimolwattanapun W Bunprapob S Vuong TB Duy Hien P Markowicz A 《The Science of the total environment》2008,404(1):103-112
Over the past decade, member states of the Regional Co-operation Agreement (RCA), an intergovernmental agreement for the East Asia and Pacific region under the auspices of the IAEA with the assistance of international organizations and financial institutions such as the World Bank and the Asian Development Bank, have started to set in place policies and legislation for air pollution abatement. To support planning and evaluate the effectiveness of control programs, data are needed that characterizes urban air quality. The focus of this measurement program describe in this report is on size segregated particulate air pollution. Such airborne particulate matter can have a significant impact on human health and urban visibility. These data provide the input to receptor models that may permit the mitigation of these impacts by identification and quantitative apportionment of the particle sources. The aim of this report is to provide an overview of the measurements of concentrations and composition of particulate air pollution in two size fractions across the participating countries. For many of the large cities in this region, the measured particulate matter concentrations are greater than air quality standards or guidelines that have been adopted in developed countries. 相似文献
992.
993.
Abdelazim Abbas Ahmed Afaque Ahmed Ismail Mohd Saaid Mirza Khurram Baig Rashidah M.Pilus 《石油科学(英文版)》2020,(3):722-733
Recently, nanoparticles have proven to enhance oil recovery on the core-flood scale in challenging high-pressure high-temperature reservoirs. Nanomaterials generally appear to improve oil production through wettability alteration and reduction in interfacial tension between oil and water phases. Besides, they are environmentally friendly and cost-effective enhanced oil recovery techniques. Studying the rheological properties of nanoparticles is critical for field applications. The instability of nanoparticle dispersion due to aggregation is considered as an unfavorable phenomenon in nanofluid flooding while conducting an EOR process. In this study, wettability behavior and rheological properties of surface-treated silica nanoparticles using internal olefins sulfonates(IOS_(20–24) and IOS_(19–23)), anionic surfactants were investigated. Surface modification effect on the stability of the colloidal solution in porous media and oil recovery was inspected. The rheology of pure and surfacetreated silica nanoparticles was investigated using a HPHT rheometer. Morphology and particle size distributions of pure and coated silica nanoparticles were studied using a field emission scanning electron microscope. A series of core-flood runs was conducted to evaluate the oil recovery factor. The coated silica nanoparticles were found to alter rheological properties and exhibited a shear-thinning behavior as the stability of the coated silica nanoparticles could be improved considerably.At low shear rates, the viscosity slightly increases, and the opposite happens at higher shear rates. Furthermore, the surfacemodified silica nanoparticles were found to alter the wettability of the aqueous phase into strongly water-wet by changing the contact angle from 80° to 3° measured against glass slides representing sandstone rocks. Oil–water IFT results showed that the surface treatment by surfactant lowered the oil–water IFT by 30%. Also, the viscosity of brine increased from 0.001 to 0.008 Pa s by introducing SiO_2 nanoparticles to the aqueous phase for better displacement efficiency during chemicalassisted EOR. The core-flood experiments revealed that the ultimate oil recovery is increased by approximately 13% with a surfactant-coated silica nanofluid flood after the conventional waterflooding that proves the potential of smart nanofluids for enhancing oil recovery. The experimental results imply that the use of surfactant-coated nanoparticles in tertiary oil recovery could facilitate the displacement efficiency, alter the wettability toward more water-wet and avoid viscous fingering for stable flood front and additional oil recovery. 相似文献
994.
Mohd Nabil Bin Muhtazaruddin Jasrul Jamani Bin Jamian Goro Fujita 《IEEJ Transactions on Electrical and Electronic Engineering》2014,9(4):351-359
Transformation of a distribution network into an intelligent and efficient system meets with many difficulties. One of most important challenges for engineers is to achieve a more economical distribution network. In addition, fluctuation in the price of oil and gas makes this task more complex. Therefore, the introduction of distributed generation (DG) in the system promises to be a good solution to reduce the dependency on oil and gas sources. However, the location and output power of DG are still an issue that needs to be solved by the utility. In previous studies, determination of DG output power and DG location are executed separately, which means a different technique is applied to each of them. Thus, it will lead the solution getting trapped in a local minimum because the calculation of optimal DG output power does not depend on the optimal DG location. This paper presents a solution to determine the location and output power of DGs simultaneously by using simultaneous artificial bee colony (SABC) to reduce the total power losses. The performance of SABC is compared with that of separate analysis, which is a combination of a single DG placement algorithm and artificial bee colony (ABC). The analysis shows that determining simultaneously the DG's location and the output gives lower total power losses and better voltage profile compared to separately analyzing the two. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
995.
Ibrahim bin Jantan Isruana Basni Abu Said Ahmad Nor Azah Mohd Ali Abdul Rashih Ahmad Halijah Ibrahim 《Flavour and Fragrance Journal》2001,16(2):110-112
The rhizome oils of Boesenbergia pandurata (Roxb.) Schlecht, water‐distilled from samples obtained from two different sites in Malaysia, Medan in Indonesia and Bangkok in Thailand, were analysed by gas chromatography on two columns of different polarity, retention indices and GC–MS. The oils were found to possess some compositional differences and considerable variation in the levels of some individual constituents, suggesting the existence of chemical varieties, which could be distinguished according to their ocimene contents. (E)‐β‐Ocimene and (Z)‐β‐ocimene, which were present in appreciable amounts in three samples, were conspicuously absent in one sample. The major constituents of the oils were camphor (16.1–32.1%), geraniol (16.2–26.0%), (E)‐β‐ocimene (19.0–23.7%), 1,8‐cineole (7.5–13.9%), camphene (5.4–6.0%) and methyl cinnamate (2.2–5.8%). Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
996.
Ling‐Zhi Cheong Chin‐Ping Tan Kamariah Long Mohd Suria Affandi Yusoff Oi‐Ming Lai 《Journal of the science of food and agriculture》2010,90(13):2310-2317
BACKGROUND: Diacylglycerol (DAG), which has health‐enhancing properties, is sometimes added to bakery shortening to produce baked products with enhanced physical functionality. Nevertheless, the quantity present is often too little to exert any positive healthful effects. This research aimed to produce bakery shortenings containing significant amounts of palm diacyglycerol (PDG). Physicochemical, textural and viscoelastic properties of the PDG bakery shortenings during 3 months storage were evaluated and compared with those of commercial bakery shortening (CS). RESULTS: PDG bakery shortenings (DS55, DS64 and DS73) had less significant increments in slip melting point (SMP), solid fat content (SFC) and hardness during storage as compared to CS. Unlike CS, melting behaviour and viscoelastic properties of PDG bakery shortenings remained unchanged during storage. As for polymorphic transformation, CS contained only β crystals after 8 weeks of storage. PDG bakery shortenings managed to retard polymorphic transformation for up to 10 weeks of storage in DS55 and 12 weeks of storage in DS64 and DS73. CONCLUSION: PDG bakery shortenings had similar if not better storage stability as compared to CS. This is mainly due to the ability of DAG to retard polymorphic transformation from β′ to β crystals. Thus, incorporation of DAG improved physical functionality of bakery shortening. Copyright © 2010 Society of Chemical Industry 相似文献
997.
Ahmad Shakerardekani Roselina Karim Hasanah Mohd Ghazali Nyuk Ling Chin 《Journal of food science》2013,78(3):S484-S489
Pistachio nut (Pistacia vera L.) is one of the most delicious and nutritious nuts in the world. Pistachio spreads were developed using pistachio paste as the main component, icing sugar, soy protein isolate (SPI), and red palm oil (RPO), at different ratios. The highest mean scores of all the sensory attributes were depicted by spreads that were made without addition of SPI. It was found that the work of shear was 0 to 11.0 kg s for an acceptable spread. Sensory spreadability, overall texture, spreadability, and overall acceptability were negatively correlated (R > 0.83) with the work of shear of spreads. The findings indicated that the presence of RPO had a direct effect on the viscoelastic behavior of the pistachio spreads. The a values, which are related to the green color of the pistachio product ranged from 1.7 to 3.9 for spread without addition of RPO, and 4.0 to 5.3 in the presence of RPO. Practical Application The development of pistachio spread would potentially increase the food uses of pistachio and introduce consumers with a healthier snack food. 相似文献
998.
Residual native starch was extracted from sago pith residue using two types of commercial cell‐wall degrading enzymes, Pectinex Ultra SP‐L and Ultrazyme 100G. The first increased starch yield with a shorter incubation period than the second. The superior effect of Pectinex Ultra SP‐L was observed already at 0.5 h, where a wide granule size distribution (8—87 μm) was obtained. A slight increase in the release of granules ranging from 30—60 μm was noted within a 2 h incubation period. However, upon further incubation, the distribution pattern was similar to that of untreated samples. Samples treated with Ultrazyme 100G exhibited a unimodal distribution pattern, with larger granules, ranging from 40—70 μm, being released upon further incubation within a 2 h incubation period. However, all samples exhibited a bimodal distribution upon further incubation. 相似文献
999.
1000.