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131.
The effects of steeping starch (sago, corn, and potato), in 0.025 M of sodium hydroxide for 0, 15, and 30 days at 30 °C, on its granular structure and other physicochemical properties were investigated. Changes in the morphology of starch granules indicated that the alkaline solution affected the granular structure of the starch. Pasting studies showed that the peak viscosity, breakdown, and setback of sago and potato starch decreased significantly, whereas that of corn starch increased significantly, when steeping time was prolonged. Swelling power increased significantly for treated potato and corn starches, but it decreased for sago starch. The amylose content of all alkali-treated starches also decreased significantly after treatment. Onset and peak temperatures of gelatinization (as analyzed with a differential scanning calorimeter) increased significantly, but the enthalpy decreased, for both gelatinization and retrogradation. The results showed that the physicochemical properties of starch of various botanical origins were affected to variable degrees when it was treated with alkaline solution. 相似文献
132.
Kin-Weng Kong Nor Fadilah Rajab K. Nagendra Prasad Amin Ismail Masturah Markom Chin-Ping Tan 《Food chemistry》2010
Effects of solvent and supercritical carbon dioxide (SC-CO2) extraction on antioxidant and cytotoxic activities of lycopene-rich fractions of decanted pink guava by-product (decanter) were determined with lycopene-equivalent antioxidant capacity, β-carotene bleaching and MTT (3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide) assays. Extraction with SC-CO2 gave a higher yield than solvent extraction (3.15 vs. 0.68 mg/100 g dried decanter, corresponding to 42.99 and 33.63 mg of lycopene). No cytotoxicity was found in Chang liver cells supplemented with either extracts (6.25–200 μg/ml). Solvent extract at 25 μg/ml (2.32 μM lycopene) and SC-CO2 extract at 200 μg/ml (5.09 μM lycopene) had protective effect against hydrogen peroxide-induced cytotoxicity. However, only high concentrations of solvent extract (200 μg/ml; lycopene = 18.65 μM) or lycopene standard (10 μM) protected cells against DNA damage. Supercritical fluid extraction demonstrated a higher yield in lycopene-rich fraction from decanter. These fractions have the potential to be developed as a functional ingredient to prevent oxidative stress and other related diseases. 相似文献
133.
Maznah Ismail Nordiana Abdul Hadi Rafiuz-Zaman Haroun Siti Nor Asma Musa Mustapha Umar Imam 《International Journal of Food Properties》2013,16(7):1449-1459
In this study, the mineral composition of germinated brown rice, brown rice, and white rice was evaluated. Brown rice grain was processed through a combination of chemical pretreatment and low oxygen treatment, after which germination was confirmed through imaging under a microscope. Using energy dispersive X-ray analysis, Mg, Al, and Cl were found to be slightly higher in germinated brown rice than in brown rice and white rice. These variations in the mineral content of germinated brown rice were attributed to the joint effect of the germination process and the prior soaking. The inability of energy dispersive X-ray to detect other minerals suggested that it was not sensitive and, hence, it was not suitable for studying elemental distribution in rice grains, or maybe the elements were not present in the rice grains studied. 相似文献
134.
Nor Azwadi Che Sidik Maysam Khakbaz Leila Jahanshaloo Syahrullail Samion Amer Nordin Darus 《Nanoscale research letters》2013,8(1):178
This paper presents a numerical study of the thermal performance of fins mounted on the bottom wall of a horizontal channel and cooled with either pure water or an Al2O3-water nanofluid. The bottom wall of the channel is heated at a constant temperature and cooled by mixed convection of laminar flow at a relatively low temperature. The results of the numerical simulation indicate that the heat transfer rate of fins is significantly affected by the Reynolds number (Re) and the thermal conductivity of the fins. The influence of the solid volume fraction on the increase of heat transfer is more noticeable at higher values of the Re. 相似文献
135.
Abdul Halim Abdullah Nor Hayati Mohd Noor Irmawati Ramli Mansor Hashim 《Materials Chemistry and Physics》2008,111(2-3):201-204
Antimony trioxide was prepared, using antimony potassium tartarate as starting material, via forward and reverse precipitation technique. The characteristics of the resulting antimony oxides were determined by BET surface area method, differential thermogravimetry analysis (DTG), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR) and SEM. The DTG curves for all uncalcined samples showed only a single endothermic peak which indicated that the sample is antimony trioxide. Unlike forward precipitation technique which resulted in a single antimony trioxide phase which is senarmontite, reverse precipitation technique produced antimony trioxide with both senarmontite and valentinite phase. Upon calcinations at 723 K, a small amount of Sb2O4 with cervantite phase was formed at the expense of Sb2O3 senarmontite phase as detected from the XRD pattern and infrared spectrum of RSb. The effect of preparation route on the properties of the antimony trioxide produced was clearly demonstrated. 相似文献
136.
Gene-Expression Programming for the Development of a Stage-Discharge Curve of the Pahang River 总被引:3,自引:2,他引:1
Hazi Mohammad Azamathulla Aminuddin Ab. Ghani Cheng Siang Leow Chun Kiat Chang Nor Azazi Zakaria 《Water Resources Management》2011,25(11):2901-2916
This study presents Gene-Expression Programming (GEP), an extension of Genetic Programming (GP), as an alternative approach
to modeling the stage-discharge relationship for the Pahang River. The results are compared to those obtained by more conventional
methods, i.e., the stage rating curve (SRC) and regression techniques. Additionally, the explicit formulations of the developed
GEP models are presented. The performance of the GEP model was found to be substantially superior to both GP and the conventional
models. 相似文献
137.
G. Niklas Norén Roland Orre Andrew Bate I. Ralph Edwards 《Data mining and knowledge discovery》2007,14(3):305-328
The WHO Collaborating Centre for International Drug Monitoring in Uppsala, Sweden, maintains and analyses the world’s largest
database of reports on suspected adverse drug reaction (ADR) incidents that occur after drugs are on the market. The presence
of duplicate case reports is an important data quality problem and their detection remains a formidable challenge, especially
in the WHO drug safety database where reports are anonymised before submission. In this paper, we propose a duplicate detection
method based on the hit-miss model for statistical record linkage described by Copas and Hilton, which handles the limited
amount of training data well and is well suited for the available data (categorical and numerical rather than free text).
We propose two extensions of the standard hit-miss model: a hit-miss mixture model for errors in numerical record fields and
a new method to handle correlated record fields, and we demonstrate the effectiveness both at identifying the most likely
duplicate for a given case report (94.7% accuracy) and at discriminating true duplicates from random matches (63% recall with
71% precision). The proposed method allows for more efficient data cleaning in post-marketing drug safety data sets, and perhaps
other knowledge discovery applications as well.
Responsible editor: Hannu Toivonen. 相似文献
138.
News
Technical news feature Palm carotenoids, tocopherols and tocotrienols 相似文献139.
The crystal structure of a low temperature modification of Mg2NiH4(LT), stable below 235°C, has been determined from Guinier-Hägg powder diffraction data. The unit cell dimensions are , , and β = 93.23(2)°. The structure has been refined by profile analysis from a sample also containing MgH2 and small amounts of two other phases, viz. the high temperature modification Mg2NiH3.9(HT) and Mg2NiHx(LT). It is indicated that the phase transformation of Mg2NiH3.9 (HT) at 235°C is eutectoid, giving mainly Mg2NiH4(LT) but also small amounts of a less hydrogen containing phase Mg2NiHx(LT) (x≈2). 相似文献
140.
Nor Hassifi Shuib Khozirah Shaari Alfi Khatib Maulidiani Ralf Kneer Seema Zareen Salahudin Mohd. Raof Nordin Hj. Lajis Victor Neto 《Food chemistry》2011
The ‘Ulam’, a traditional Malay dish, are plants that can be eaten raw, as a form of local salad. The shoots and young leaves of Melicope ptelefolia are among the popular species, believed to be high in nutritional and medicinal values. The metabolomic fingerprinting analysis of the ethanolic extracts of leaves of M. ptelefolia was carried out using 1H Nuclear Magnetic Resonance (NMR) spectroscopy and multivariate data analysis in order to differentiate young and mature leaves and to evaluate the variation of their chemical composition. Principle component analysis (PCA) of the 1H NMR spectra showed a clear discrimination between the young and mature leaves extracts by PC3 and PC4. The compounds responsible for the differentiation were identified by comparison of 1H NMR chemical shifts and qualitative HPLC. The young leaves were found to be richer in fatty acids and the levels of the three marker compounds, p-O-geranylcoumaric acid, 2,4,6-trihydroxy-3-geranylacetophenone and 2,4,6-trihydroxy-3-prenylacetophenone, were clearly higher. The mature leaves contain higher levels of sugars and glycosidic components. 相似文献