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191.
Simultaneous adsorption of a mixture of paraquat and dye by NaY zeolite covered with alkylsilane 总被引:1,自引:0,他引:1
The surfaces of NaY zeolite particles were modified by the alkylsilylation of n-octadecyltrichlorosilane (OTS). Two kinds of modified NaY zeolites were prepared; one with its external surface partially and the other fully covered with alkylsilyl groups. Since the size of OTS is bigger than the pore diameter of NaY, it is attached on the external surface, leaving the internal pore accessible to adsorbate molecules. As a result of alkylsilylation, the adsorption properties of these sorbents were improved. The adsorption properties of these materials were tested by their reaction in a mixture of paraquat and blue dye. The results demonstrate that the alkysilylated NaY materials are capable of simultaneous adsorption of paraquat and blue dye. Paraquat was selectively adsorbed into the internal pore of the zeolite whereas the dye on the externally attached alkylsilyl groups of the sorbent; displaying the unique bimodal amphiphilic character of the alkylsilylated NaY zeolites. 相似文献
192.
Ibrahim F Taib MN Abas WA Guan CC Sulaiman S 《Computer methods and programs in biomedicine》2005,79(3):273-281
Dengue fever (DF) is an acute febrile viral disease frequently presented with headache, bone or joint and muscular pains, and rash. A significant percentage of DF patients develop a more severe form of disease, known as dengue haemorrhagic fever (DHF). DHF is the complication of DF. The main pathophysiology of DHF is the development of plasma leakage from the capillary, resulting in haemoconcentration, ascites, and pleural effusion that may lead to shock following defervescence of fever. Therefore, accurate prediction of the day of defervescence of fever is critical for clinician to decide on patient management strategy. To date, no known literature describes of any attempt to predict the day of defervescence of fever in DF patients. This paper describes a non-invasive prediction system for predicting the day of defervescence of fever in dengue patients using artificial neural network. The developed system bases its prediction solely on the clinical symptoms and signs and uses the multilayer feed-forward neural networks (MFNN). The results show that the proposed system is able to predict the day of defervescence in dengue patients with 90% prediction accuracy. 相似文献
193.
Shahin Roohinejad Alireza Omidizadeh Hamed Mirhosseini Nazamid Saari Shuhaimi Mustafa Rokiah Mohd Yusof Anis Shobirin Meor Hussin Azizah Hamid Mohd Yazid Abd Manap 《Journal of the science of food and agriculture》2010,90(2):245-251
BACKGROUND: Brown rice is unpolished rice with immeasurable benefits for human health. Brown rice (BR) and pre‐germinated brown rice (PGBR) are known to contain various functional compounds such as γ‐oryzanol, dietary fibre and γ‐aminobutyric acid (GABA). In the present study, the experimental diets containing BR and PGBR (24, 48 h pre‐germination) were used to investigate the influence of pre‐germination time of brown rice on blood cholesterol in Sprague–Dawley male rats. RESULTS: Hypercholesterolaemia and elevation of LDL‐cholesterol were successfully ameliorated by the experimental diets containing BR and PGBR (24 and 48 h pre‐germination). As compared to the control sample, the pre‐germination time had a significant (P < 0.05) effect on blood cholesterol of Sprague–Dawley male rats. It was also found that the significantly (P < 0.05) better effect on lipid profile of hypercholesterolaemic rats was observed by prolonging the pre‐germination time. As compared to non‐germinated brown rice, the germinated brown rice showed the higher cardio‐protective effect on hypercholesterolaemic Sprague–Dawley male rats. CONCLUSION: The present study suggests that the changes of blood cholesterol can be mainly modulated by using the PGBR rather than BR. The prolonging of pre‐germination time led to an increase in the bioactive components, thereby providing a more efficient functional diet affecting the high blood cholesterol. This study suggests that PGBR can be used instead of BR and polished rice in the human diet. Copyright © 2009 Society of Chemical Industry 相似文献
194.
Rasif Mohd Zain Ruzairi Abdul Rahim Mohd Hafiz Fazalul Rahiman Jaafar Abdullah 《Sensing and Imaging: An International Journal》2010,11(2):33-50
This paper presents a novel method of combining dual modality electrical capacitance and optical tomography for applications
in monitoring and investigating solid/gas flow. The objective of this method is to obtain a good quality image of the full-scale
concentration distribution of solid/gas flow. A new image reconstruction algorithm fused the dual modality images is developed
and evaluated. 相似文献
195.
Mohd.Zahed M.Khan 《光电子快报》2009,5(3):198-201
A waveguide crossing utilizing a high index contrast material system is presented. The structure is based on coupling with an octagonal resonant cavity inserted at the waveguide junction. It also employs four identical square metal strips placed at the four comers of the waveguide crossing. The spectral response of the structure calculated using the method of line numerical technique, in general, shows a high power transmission in the forward arm with sufficiently low crosstalk and fraction of radiated power. 相似文献
196.
Ethanol and lactic acid production using sap squeezed from old oil palm trunks felled for replanting
Akihiko Kosugi Ryohei Tanaka Kengo Magara Yoshinori Murata Takamitsu Arai Othman Sulaiman Rokiah Hashim Zubaidah Aimi Abdul Hamid Mohd Khairul Azri Yahya Mohd Nor Mohd Yusof Wan Asma Ibrahim Yutaka Mori 《Journal of Bioscience and Bioengineering》2010,110(3):322-325
Old oil palm trunks that had been felled for replanting were found to contain large quantities of high glucose content sap. Notably, the sap in the inner part of the trunk accounted for more than 80% of the whole trunk weight. The glucose concentration of the sap from the inner part was 85.2 g/L and decreased towards the outer part. Other sugars found in relatively low concentrations were sucrose, fructose, galactose, xylose, and rhamnose. In addition, oil palm sap was found to be rich in various kinds of amino acids, organic acids, minerals and vitamins. Based on these findings, we fermented the sap to produce ethanol using the sake brewing yeast strain, Saccharomyces cerevisiae Kyokai no.7. Ethanol was produced from the sap without the addition of nutrients, at a comparable rate and yield to the reference fermentation on YPD medium with glucose as a carbon source. Likewise, we produced lactic acid, a promising material for bio-plastics, poly-lactate, from the sap using the homolactic acid bacterium Lactobacillus lactis ATCC19435. We confirmed that sugars contained in the sap were readily converted to lactic acid with almost the same efficiency as the reference fermentation on MSR medium with glucose as a substrate. These results indicate that oil palm trunks felled for replanting are a significant resource for the production of fuel ethanol and lactic acid in palm oil-producing countries such as Malaysia and Indonesia. 相似文献
197.
Wan Azelee Wan Abu Bakar Mohd Yusuf Othman Rusmidah Ali Ching Kuan Yong 《Catalysis Letters》2009,128(1-2):127-136
Supported nickel oxide based catalysts were prepared by wetness impregnation method for the in-situ reactions of H2S desulfurization and CO2 methanation from ambient temperature up to 300 °C. Fe/Co/Ni (10:30:60)–Al2O3 and Pr/Co/Ni (5:35:60)–Al2O3 catalysts were revealed as the most potential catalysts, which yielded 2.9% and 6.1% of CH4 at reaction temperature of 300 °C, respectively. From XPS, Ni2O3 and Fe3O4 were suggested as the surface active components on the Fe/Co/Ni (10:30:60)–Al2O3 catalyst, while Ni2O3 and Co3O4 on the Pr/Co/Ni (5:35:60)–Al2O3 catalyst. 相似文献
198.
Ahmad Adlie Shamsuri Rusli Daik Ishak Ahmad Mohd Hafizuddin Hj. Jumali 《Journal of Polymer Research》2009,16(4):381-387
Nylon-6 is widely used as engineering plastic because it is easy to process, high tensile properties, resistant to chemical
and abrasion. However, poor impact strength at low temperature makes it limitedly used in some applications. Nylon-6/liquid
natural rubber (LNR) blends were prepared via emulsion dispersion with composition of 100nylon-6/0LNR, 95nylon-6/5LNR, 90nylon-6/10LNR,
85nylon-6/15LNR, 80nylon-6/20LNR and 75nylon-6/25LNR. Nylon-6 was dissolved in a 2,2,2-trifluoroethanol and chloroform mixture
(1:1 TFE/CHCl3) and emulsified with hexadecyltrimethylammonium bromide (HTAB). LNR was dispersed into the nylon-6 emulsion to form homogeneous
nylon-6/LNR emulsions and the emulsions were de-emulsified with methanol, filtered and dried. High impact behaviour was achieved
at 85nylon-6/15LNR composition. DSC thermogram indicated a single glass transition temperature, T
g and SEM images showed no phase separation between blend components implying homogeneous blends were obtained. 相似文献
199.
Hongngee Lim Anuar Kassim Nayming Huang Mohd. Ambar Yarmo 《Journal of surfactants and detergents》2009,12(4):355-362
In the present study, a series of as-synthesized palm-based nonionic surfactants with various hydrophile–lipophile balance values were successfully synthesized. The critical micelle concentration and the Gibbs energy of the surfactants were determined and discussed. For the first time, the surfactants were used to stabilize three-component olein oil-in-water high internal phase emulsions, with an oil volume fraction of 0.85, and which were easily prepared by one-pot homogenization. Proof of high stability was confirmed by the satisfactory rheological profiles and further enhanced by a three-month storage exercise at an elevated temperature which showed no significant physical and rheological changes. These results suggest that low concentration of the surfactants efficiently stabilized the emulsions with high content of oil. Based on the optical micrograph observation, an average droplet size of less than 10 μm increased with increasing ethylene oxide chain length and temperature. The varying degree of viscosity resulted from the various ethylene oxide chain lengths of the surfactants. The hydration efficacy of the emulsions was examined in vivo using a corneometer. The impressive hydration efficacy of olein oil suggests that it could well be a potential moisturizing lipid which might interest dermatologists. 相似文献
200.
Pooria Pasbakhsh Hanafi Ismail Mohd Noor Ahmad Fauzi Azhar Abu Bakar 《应用聚合物科学杂志》2009,113(6):3910-3919
The effect of partial replacement of silica or calcium carbonate (CaCO3) by halloysite nanotubes (HNTs) on the curing behavior, tensile properties, dynamic mechanical properties, and morphological characteristics of ethylene propylene diene monomer (EPDM) composites was studied. Five different compositions of EPDM/Silica/HNT and EPDM/CaCO3/HNT compounds (i.e. 100/30/0, 100/25/5, 100/15/15, 100/5/25, and 100/0/30 parts per hundred rubber (phr)) were prepared on a two‐roll mill. The results indicated that the replacement of CaCO3 by HNTs increased the tensile strength, elongation at break (Eb), and tensile modulus of composites from 0 to 30 phr of HNTs whereas for silica, the maximum tensile strength and Eb occurred at 5 phr loading of HNTs with an enhanced stress at 300% elongation (M300). The curing results show that, with replacement of silica or CaCO3 by HNTs, the cure time (t90) and cure rate (CRI) were decreased and increased, respectively. Scanning electron microscopy investigation confirmed that co‐incorporation of 5 phr of HNTs with silica would improve the dispersion of silica and enhanced the interactions between fillers and EPDM matrix. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献