476 research outputs found

    Cobalt oxide-modified titanium dioxide nanoparticle photocatalyst for degradation of 2,4-dichlorophenoxyacetic acid

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    2,4-dichlorophenoxyacetic acid (2,4-D) has been recognized as a possibly carcinogenic compound to human, therefore, 2,4-D should be treated before it is discharged to the environment. Photocatalytic degradation of 2,4-D has been proposed as one of the best methods that offer environmentally safe process. In the present research, titanium dioxide (TiO2) was modified with cobalt oxide (CoO) and tested for photocatalytic degradation of 2,4-D under UV light irradiation. Different amounts of CoO (0.1, 0.5, 1 and 5 mol%) were added onto TiO2 by an impregnation method. The photocatalytic reaction was monitored and analyzed by measurement of 2,4-D absorbance using UV spectrophotometer. After 1 h photocatalytic reaction, it was confirmed that the sample with low loading of 0.1 mol% gave the highest photocatalytic activity among the bare and modified TiO2 photocatalysts. The photocatalytic activity was decreased with the increase of CoO loading, suggesting that the optimum amount of CoO was an important factor to improve the performance of TiO2. Based on fluorescence spectroscopy, such addition of CoO resulted in the reduced emission intensity, which showed the successful decrease in the electron-hole recombination

    UPC barcode apps for drug registered verification

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    In pharmacology, drug is used to prevent and cure diseases and to improve the physical or mental well-being. All medicinal products must be registered with Drug Control Authority (DCA) of Malaysia before being marketed. However, there are still numerous unregistered products being sold in night markets and grocery stalls that contained unknown materials that could harm our bodies. As nowadays most people own smartphones, thus it will be great if the smartphone is being utilized to become a mobile apps that can prevent consumers from buying unregistered products. This study described the process of creating a barcode reader application for drug registered verification. The application is created using Android Studio software, Java programming language and source code from GitHub, which is then synchronized with the database of some medicinal products. The barcode scanner is then tested to read the UPC barcode on the products and the result of registration confirmation will be shown on the screen of the smartphone. Thus, it will aware the user from buying the unregistered products

    Turning Natural Fiber Reinforced Cement Composite as Innovative Alternative Sustainable Construction Material: A Review Paper

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    In recent years, a great deal of interest in concrete leads to the most frequently used sustainable construction material. Using of natural fiber as fiber reinforcement effectively improved strength, ductility and durability requirements of high performance cement composites. Regretly, natural fibers are dumped as agricultural waste (e.g. coconut, bamboo, wood or chips, bast fiber, leaf fiber, seed and fruit fibers, etc), so can be easily available low cost. The applications of natural fiber for sustainable construction material design can be done as filler or masonry composites, reinforcement, thermal conductivity, cementations/binder, etc. Previous and current researchers focusing the natural fiber to improve the properties of lightweight composites still required a lot of investigations to make it improved. However, the present work consists of the availability of natural fiber waste substance, sustainable construction materials are evaluated for their physico-mechanical properties of sustainable construction materials, method of production and environmental impact of several materials. No doubt, the application of natural fiber provides a solution to conservation of natural resource and energy

    Influence of yarn parameters on cotton/kenaf blended yarn characteristics

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    Spinning kenaf fibers into yarns is challenging due to the stiffness and lack of cohesiveness of the fibers. Alkali treatment is known to remove hemicellulose, wax, and breaks down lignin, reducing stiffness of kenaf fiber and improving its spinnability. Kenaf fibers were treated at percentages of 4% and 6% and blended with cotton fibers at blend ratios of 40:60 and 50:50 prior to a ring spinning process to produce a double ply yarn of 70 tex. Yarn were twisted at three sets of twist. The responses were measured in terms of carding waste percentages and yarn strength. The results showed that the optimized yarn structural parameter is kenaf fiber treated at 6% and with a kenaf/cotton 40/60 blending ratio based on its tenacity and minimum carding waste. ANOVA shows that there is a good interaction effect between NaOH and kenaf/cotton ratio, and NaOH concentration and twist

    Graphic Organizer in Action: Solving Secondary Mathematics Word Problems

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    Mathematics word problems are one of the most challenging topics to learn and teach in secondary schools. This is especially the case in countries where English is not the first language for the majority of the people, such as in Brunei Darussalam. Researchers proclaimed that limited language proficiency and limited Mathematics strategies are the possible causes to this problem. However, whatever the reason is behind difficulties students face in solving Mathematical word problems, it is perhaps the teaching and learning of the Mathematics that need to be modified. For example, the use of four-square-and-a-diamond graphic organizer that infuses model drawing skill; and Polya\u27s problem solving principles, to solve Mathematical word problems may be some of the strategies that can help in improving students\u27 word problem solving skills. This study, through quantitative analysis found that the use of graphic organizer improved students\u27 performance in terms of Mathematical knowledge, Mathematical strategy and Mathematical explanation in solving word problems. Further qualitative analysis revealed that the use of graphic organizer boosted students\u27 confidence level and positive attitudes towards solving word problems

    Hollow-core photonic crystal fiber refractive index sensor based on modal interference

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    A refractive index sensor based modal interference in hollow core photonic crystal fiber (HCPCF) is proposed and demonstrated. The sensor is realized by splicing both ends of a HCPCF section to single mode fiber (SMF). At both splicing points, the HCPCF air holes are fully collapsed by the arc discharge. The collapsed regions excite and recombine core and cladding modes which formed modal interference for sensing purpose. The HCPCF sensor is tested in sugar solution and the response is measured from the wavelength shift in the interference spectra. The achieved sensitivity and resolution are 36.184 nm/RIU and 5.53-10-4 RIU, respectively, in refractive index range between 1.3330 and 1.3775. Result also shows that the sensor has a small temperature sensitivity of 19 pm/°C in the range of 35.5°C to 60.5 °C. The propos sensor potentially can be applied in biomedical, biological and chemical applications

    Diuretic properties of Orthosiphon stamineus Benth.

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    Ethnopharmacological relevance: Orthosiphon stamineus has been used in traditional medicine for centuries especially to treat diseases of the urinary system. Aim of the study: To investigate the diuretic activity, to elucidate its possible mechanism and to evaluate the renal effects of Orthosiphon stamineus extract. Materials and methods: Water extracts were administered orally at doses of 5 and 10 mg/kg to Sprague-Dawley rats and the control groups were given commercial diuretic drugs either furosemide or hydrochlorthiazide at 10 mg/kg. Urine volume, urine pH, urine density and urine electrolytes were determined every hour for 4 h. Blood was assayed for glucose, albumin, blood urea nitrogen (BUN) and creatinine. Results: O. stamineus extract exhibited dose-dependent diuretic activity. However, excretion of Na+ and Cl- was not markedly elevated, but urinary excretion of K+ was significantly increased. O. stamineus extracts slightly increased the serum BUN, creatinine and blood glucose level. Although these levels were statistically significant when compared to control, these levels were still within normal range. Conclusions: O. stamineus exhibited diuretic activity, but was less potent than furosemide and hydrochlorothiazide. Care should be taken when consuming this herb as slight increase of kidney function enzymes was recorded

    Deforestation awareness among the community living near mangroves in Mukim Tanjung Kupang, Johor, Malaysia

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    A study was carried out on the deforestation awareness among the community living nearest to Sungai Pulai mangrove forest under mukim (sub-district) Tanjung Kupang in Johor Bahru, Peninsular Malaysia. A Structured questionnaire was used to collect data on respondents’ socioeconomic condition, their familiarity to mangroves and awareness from six villages which have been selected randomly. Majority of the respondents were male, Malay, Muslim and from middle aged group. About 82% respondents had some level of education. Average household size was 5.5. About 71% respondents’ livelihoods were dependent on mangrove ecosystem of which 65% were fishermen, 5% aquaculture and 1% tourism. Mean monthly income of respondents was quite lower than national average income. Moreover, monthly average income of mangrove dependent group was lower than the non mangrove dependent group. About 93% of the respondents were somehow familiar to mangroves. Responden ts mean awareness score of 3.78 indicates respondents were aware about the mangroves. It was also found that male had significantly higher awareness than female for two out of ten awareness components. Likewise,mangrove dependent group had significantly higher awareness than the non- mangrove dependent group for six out of ten awareness components

    Effect of nano-sized Co3O4 addition on the transport properties of YBa2Cu3O7−δ

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    The effect of nano-sized Co3O4 (10 - 30 nm) addition on YBa2Cu3O7−δ(Co3O4)x with x = 0 to 0.12 wt.% has been investigated by powder X-ray diffraction method, dc electrical resistance measurements and scanning electron microscopy. The Co3O4 particle size was larger than the coherence length but smaller than the penetration depth of the YBa2Cu3O7−δ superconductor. The onset transition temperature (T c onset) showed no significant changes for low Co3O4 addition (x ≤ 0.02 wt. %) and then decreased monotonically with the increase in Co3O4 content indicating a pair-breaking like mechanism in T c suppression for x = 0.03 to 0.12 wt. %. A sudden broadening of the superconducting-transition-width for x ≥ 0.11 wt. % was also observed. The transport properties were measured and related to the microstructure. Scanning electron micrographs showed homogeneous distribution of Co3O4 throughout the samples and the distance between particles was smaller than 1 μm but larger than the typical Abrikosov vortex lattice constant

    In vitro antiproliferative and antioxidant activities of the extracts of Muntingia calabura leaves.

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    The in vitro antiproliferative and antioxidant activities of the aqueous, chloroform and methanol extracts of Muntingia calabura leaves were determined in the present study. Assessed using the 3,(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay, the aqueous and methanol extracts of M. calabura inhibited the proliferation of MCF-7, HeLa, HT-29, HL-60 and K-562 cancer cells while the chloroform extract only inhibited the proliferation of MCF-7, HeLa, HL-60 and K-562 cancer cells. Interestingly, all extracts of M. calabura, which failed to inhibit the MDA-MB-231 cells proliferation, did not inhibit the proliferation of 3T3 (normal) cells, indicating its safety. All extracts (20, 100 and 500 μg/ml) were found to possess antioxidant activity when tested using the DPPH radical scavenging and superoxide scavenging assays with the methanol, followed by the aqueous and chloroform, extract exhibiting the highest antioxidant activity in both assays. The total phenolic content for the aqueous, methanol and chloroform extracts were 2970.4 ± 6.6, 1279.9 ± 6.1 and 2978.1 ± 4.3 mg/100 g gallic acid, respectively. In conclusion, the M. calabura leaves possess potential antiproliferative and antioxidant activities that could be attributed to its high content of phenolic compounds, and thus, needs to be further explored
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