Displaying publications 1361 - 1380 of 10538 in total

Abstract:
Sort:
  1. Torch Ginger (Etlingera elatior): A Review on its Botanical Aspects, Phytoconstituents and Pharmacological Activities
    Juwita T, Melyani Puspitasari I, Levita J
    Pak J Biol Sci, 2018 Jan;21(4):151-165.
    PMID: 30311471 DOI: 10.3923/pjbs.2018.151.165
    In order to propose a prospective candidate for novel complementary phytopharmaceuticals, one of Zingiberaceae family plant, Etlingeraelatior or torch ginger, was being evaluated. The aim of this review was to provide a comprehensive literature research focused on the botanical aspects, nutritional quality, phytoconstituents and pharmacological activities of E. elatior. Researches on this particular plant were conducted in Malaysia (55.5%), Indonesia (33.3%), Thailand (8.3%) and Singapore (2.7%). This review article has revealed that the most prominent pharmacological activities were anti-microbial, anti-oxidant and anti-tumor activities in consistent with the dominated levels of flavonoids, terpenoids and phenols. However, extended and integrated research should be converged towards intensive investigations concerning to isolated phytoconstituents and its bioactivities, pharmacokinetics, bioavailability, molecular mechanism of its specific pharmacological activities, safety and efficacy studies for further development.
    Matched MeSH terms: Plant Extracts/chemistry*; Ginger/chemistry*
  2. Development of a novel direct compressible co-processed excipient and its application for formulation of Mirtazapine orally disintegrating tablets
    Loke YH, Chew YL, Janakiraman AK, Lee SK, Uddin ABMH, Goh CF, et al.
    Drug Dev Ind Pharm, 2024 Jan;50(1):36-44.
    PMID: 38149637 DOI: 10.1080/03639045.2023.2294095
    INTRODUCTION: Orally disintegrating tablets (ODTs) are designed to dissolve in the oral cavity within 3 min, providing a convenient option for patients as they can be taken without water. Direct compression is the most common method used for ODTs formulations. However, the availability of single composite excipients with desirable characteristics such as good compressibility, fast disintegration, and a good mouthfeel suitable for direct compression is limited.

    OBJECTIVE: This research was proposed to develop a co-processed excipient composed of xylitol, mannitol, and microcrystalline cellulose for the formulation of ODTs.

    METHODS: A total of 11 formulations of co-processed excipients with different ratios of ingredients were prepared, which were then compressed into ODTs, and their characteristics were thoroughly examined. The primary focus was on evaluating the disintegration time and hardness of the tablets, as these factors are important in ensuring the ODTs meet the desired criteria. The model drug, Mirtazapine was then incorporated into the chosen optimized formulation.

    RESULTS: The results showed that the formulation comprised of 10% xylitol, 10% mannitol and 80% microcrystalline cellulose demonstrated the fastest disintegration time (1.77 ± 0.119 min) and sufficient hardness (3.521 ± 0.143 kg) compared to the other formulations. Furthermore, the drug was uniformly distributed within the tablets and fully released within 15 min.

    CONCLUSION: Therefore, the developed co-processed excipients show great potential in enhancing the functionalities of ODTs, offering a promising solution to improve the overall performance and usability of ODTs in various therapeutic applications.

    Matched MeSH terms: Mannitol/chemistry; Tablets/chemistry
  3. Sargassum myriocystum-mediated TiO2-nanoparticles and their antimicrobial, larvicidal activities and enhanced photocatalytic degradation of various dyes
    Balaraman P, Balasubramanian B, Liu WC, Kaliannan D, Durai M, Kamyab H, et al.
    Environ Res, 2022 Mar;204(Pt C):112278.
    PMID: 34757031 DOI: 10.1016/j.envres.2021.112278
    Recently, the phyco-synthesis of nanoparticles has been applied as a reliable approach to modern research field, and it has yielded a wide spectrum of diverse uses in fields such as biological science and environmental science. This study used marine natural resource seaweed Sargassum myriocystum due to their unique phytochemicals and their significant attributes in giving effective response on various biomedical applications. The response is created by their stress-tolerant environmental adaptations. This inspired us to make an attempt using the above-mentioned charactersitics. Therfore, the current study performed phycosynthesis of titanium dioxide nanoparticles (TiO2-NPs) utilising aqueous extracts of S. myriocystum. The TiO2-NPs formation was confirmed in earlier UV-visible spectroscopy analysis. The crystalline structure, functional groups (phycomolecules), particle morphology (cubic, square, and spherical), size (∼50-90 nm), and surface charge (negative) of the TiO2-NPs were analysed and confirmed by various characterisation analyses. In addition, the seaweed-mediated TiO2-NPs was investigated, which showed potential impacts on antibacterial activity and anti-biofilm actions against pathogens (Staphylococcus aureus, S. epidermidis, Escherichia coli, Proteus vulgaris, Pseudomonas aeruginosa, and Klebsiella pneumoniae). Additionally, some evaluations were performed on larvicidal activities of TiO2-NPs in oppose to Aedes aegypti and Culex quinquefasciatus mosquitos and the environmental effects of photocatalytic activities against methylene blue and crystal violet under sunlight irradiation. The highest percent of methylene blue degradation was observed at 92.92% within 45 min. Overall, our findings suggested that S. myriocystum mediates TiO2-NPs to be a potent disruptive material for bacterial pathogens and mosquito larvae and also to enhance the photocatalytic dye degradation.
    Matched MeSH terms: Anti-Bacterial Agents/chemistry; Titanium/chemistry
  4. Isolation, purification and characterization of β-glucan from cereals - A review
    Sujithra S, Arthanareeswaran G, Ismail AF, Taweepreda W
    Int J Biol Macromol, 2024 Jan;256(Pt 1):128255.
    PMID: 37984576 DOI: 10.1016/j.ijbiomac.2023.128255
    β-glucans are soluble fibers found in cereal compounds, including barley, oats etc., as an active component. They are used as a dietary fiber to treat cholesterol, diabetes and cardiovascular diseases. These polysaccharides are important because they can provide many therapeutic benefits related to their biological activity in human like inhibiting tumour growth, anti-inflammatory action, etc. All these activities were usually attached to their molecular weight, structure and degree of branching. The present manuscript reviews the background of β-glucan, its characterization techniques, the possible ways to extract β-glucan and mainly focuses on membrane-based purification techniques. The β-glucan separation methods using polymeric membranes, their operational characteristics, purification methods which may yield pure or crude β-glucan and structural analysis methods were also discussed. Future direction in research and development related to β-glucan recovery from cereal were also offered.
    Matched MeSH terms: Edible Grain/chemistry; Avena/chemistry
  5. Thermal properties analysis and thermal cycling of HITEC molten salt with h-BN nanoparticles for CSP thermal energy storage applications
    Suraparaju SK, Aljaerani HA, Samykano M, Kadirgama K, Noor MM, Natarajan SK
    Environ Sci Pollut Res Int, 2024 Aug;31(38):50166-50178.
    PMID: 38625473 DOI: 10.1007/s11356-024-33151-x
    Molten salts are the operational fluid for most concentrated solar power (CSP) systems, which has attracted more attention among the scientific community due to the augmentation of their properties with the doping of nanoparticles. Hexagonal boron nitride (h-BN) nanoparticles were dispersed in HITEC molten salt to create a novel nanofluid and evaluate the h-BN nanoparticles' influence on HITEC thermophysical properties. The influence of nanoparticle concentration (0.1, 0.5, and 1wt.%) of h-BN and HITEC was studied in this research. HITEC and nano-enhanced HITEC molten salt (NEHMS) were characterized using energy-dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FESEM), and Fourier transform infrared spectroscopy (FT-IR). Specific heat capacity, latent heat, and melting temperature were assessed using differential scanning calorimetry (DSC). The maximum working temperature was evaluated with thermogravimetric analysis (TGA). The ideal nanoparticle concentration is 0.1 wt.% h-BN, which results in a 27% increase in heat capacity, a 72% increase in latent heat, and a 7% enhancement in thermal stability. The thermal cycling stability test proved the stability of the enhanced thermophysical properties. The material characterization revealed that the samples with improved thermophysical properties have a homogeneous dispersion of nanoparticles with minor nanoparticle agglomeration. The system advisor model (SAM) simulation comparison of the optimum sample with solar salt and HITEC salt revealed that using the optimum sample increases CSP plant efficiency by 0.4% and reduces power costs by 0.13¢/kWh.
    Matched MeSH terms: Boron Compounds/chemistry; Salts/chemistry
  6. Optimization of subcritical water extraction for pectin extraction from cocoa pod husks using the response surface methodology
    Anoraga SB, Shamsudin R, Hamzah MH, Sharif S, Saputro AD, Basri MSM
    Food Chem, 2024 Nov 30;459:140355.
    PMID: 38986202 DOI: 10.1016/j.foodchem.2024.140355
    This study optimized subcritical water extraction (SWE) conditions to maximize pectin yield from cocoa pod husk (CPH) and compared the characteristics of CPH pectin extracted through SWE with those of CPH pectin obtained through conventional extraction (CE) with citric acid. The Box-Behnken experimental design was employed to optimize SWE and examine the influence of process parameters, including temperature (100 °C-120 °C), extraction time (10-30 min), and solid:liquid ratio (SLR) (1:30-2:30 g/mL), on pectin yield. The maximum pectin yield of 6.58% was obtained under the optimal extraction conditions of 120 °C for 10 min with 1:15 g/mL SLR and closely corresponded with the predicted value of 7.29%. Compared with CE, SWE generated a higher yield and resulted in a higher degree of esterification, methoxyl content, and anhydrouronic acid value but a lower equivalent weight. The extracted pectin was pure, had low-methoxyl content, and similar melting and degradation temperatures.
    Matched MeSH terms: Plant Extracts/chemistry; Water/chemistry
  7. Colorimetric and fluorometric sensing of polar E120 in juice and environmental water samples using mannitol-functionalized magnetic nanoparticles and nitrogen-doped carbon dots
    Aburub SS, Rahim NY, Mahmoud AM, Maluin FN
    Spectrochim Acta A Mol Biomol Spectrosc, 2025 Feb 15;327:125380.
    PMID: 39522227 DOI: 10.1016/j.saa.2024.125380
    In this study, mannitol-functionalized magnetic nanoparticles (MMNPs) as a unique nanosorbent and N-doped fluorescent carbon dots (N-CDs) as a cost-effective nanosensor were created and utilized, for the first time, for dispersive micro-solid-phase extraction (Dµ-SPE) to determine carmine (E120) dye in water samples and juices. The modification of the magnetic nanoparticles with mannitol was designed to enhance the responsive potential for adsorption of the polar E120 dye from complex sample matrices through electrostatic interaction. The as-fabricated N-CDs fluorescent probe exhibited a high fluorescence quantum yield (Φs) of 43.1 %, allowing for accurate fluorometric detection of E120 dye. The as-synthesized MMNPs nanosorbent and fluorescent N-CDs nanoprobe were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), energy dispersive X-ray (EDX), thermogravimetric analysis (TGA), and vibrating-sample magnetometer (VSM). Density functional theory (DFT) studied the E120 dye structure using Gaussian 09 to explore the interactions between E 120 dye molecules and MMNPs/N-CDs. The impact of the critical adsorption and detection experimental factors was investigated and adjusted. A minimal amount of MMNPs nanosorbent (150 mg) is sufficient for E120 extraction in an acceptable time of 15 min. Furthermore, with a high determination coefficient, the adsorption characteristics fit with the models of Langmuir isotherm and first-order kinetics. The maximum adsorption capacity (qm) of the as-fabricated MMNPs was 87.7 mg.g-1. After adsorption, E120 dye was fluorometrically analyzed using nitrogen-doped carbon dots as a fluorescent nanosensor via the inner filter effect (IFE) mechanism. Under the optimized conditions, the proposed fluorometric procedures showed a linear increase in the fluorescence ratio with increasing the E120 concentration in the range of 1.0 - 160.0 μg.mL-1 with detection (LOD) and quantitation (LOQ) limits of 0.27 and 0.83 μg.mL-1, respectively. The relative standard deviation (%RSD) did not exceed 2.34 %. The proposed methodology was successfully applied to determine E120 dye in juice and environmental water samples with % recovery ranged from 89.2-106.1 % and 92.9-107.2 %, respectively offering a reliable and environmentally friendly alternative to traditional detection methods with potential applications across various industries.
    Matched MeSH terms: Water/chemistry; Magnetite Nanoparticles/chemistry
  8. An Overview of Crosslinked Enzyme Aggregates: Concept of Development and Trends of Applications
    Bouguerra OM, Wahab RA, Huyop F, Al-Fakih AM, Mahmood WMAW, Mahat NA, et al.
    Appl Biochem Biotechnol, 2024 Sep;196(9):5711-5739.
    PMID: 38180645 DOI: 10.1007/s12010-023-04809-y
    Enzymes are commonly used as biocatalysts for various biological and chemical processes in industrial applications. However, their limited operational stability, catalytic efficiency, poor reusability, and high-cost hamper further industrial usage. Thus, crosslinked enzyme aggregates (CLEAs) are developed as a better enzyme immobilization tool to extend the enzymes' operational stability. This immobilization method is appealing because it is simpler due to the absence of ballast and permits the collective use of crude enzyme cocktails. CLEAs, so far, have been successfully developed using a variety of enzymes, viz., hydrolases, proteases, amidases, lipases, esterases, and oxidoreductase. Recent years have seen the emergence of novel strategies for preparing better CLEAs, which include the combi- and multi-CLEAs, magnetics CLEAs, and porous CLEAs for various industrial applications, viz., laundry detergents, organic synthesis, food industries, pharmaceutical applications, oils, and biodiesel production. To better understand the different strategies for CLEAs' development, this review explores these strategies and highlights the relevant concerns in designing innovative CLEAs. This article also details the challenges faced during CLEAs preparation and solutions for overcoming them. Finally, the trending strategies to improve the preparation of CLEAs alongside their industrial application trends are also discussed.
    Matched MeSH terms: Cross-Linking Reagents/chemistry; Lipase/chemistry
  9. Fulltext Unveiling the role of mechanical process intensifications and chemical additives in boosting lipase-catalyzed hydrolysis of vegetable oil for fatty acid production: A comprehensive review
    Ng WZ, Chan ES, Gourich W, Adiiba SH, Liow MY, Ooi CW, et al.
    Int J Biol Macromol, 2025 Jan;284(Pt 1):138144.
    PMID: 39613062 DOI: 10.1016/j.ijbiomac.2024.138144
    The enzymatic production of fatty acids from vegetable oils is becoming a preferred method due to its mild conditions, simplicity, and scalability. This review analyzes studies on enzymatic hydrolysis, exploring various feedstocks, lipases, reaction conditions, and conversion yields. However, a key limitation is the longer reaction time compared to conventional methods. This limitation is primarily due to the immiscibility of triacylglycerols (TAGs) with water at low temperatures and pressures, as well as the lower activity of enzymes compared to chemical catalysts. To overcome these issues, chemical additives are identified as the most effective process intensification strategy. They are easy to implement, cause less damage to lipases, and are more efficient than mechanical methods. The impact of various chemical additives was thoroughly examined for potential improvements in the enzymatic hydrolysis of vegetable oils. A synergistic combination of chemical additives comprising ionic liquids (ILs) and polyols, along with ultrasound, as well as the consideration of immobilization techniques were explored. Overall, this review highlights the potential of chemical additives and their synergistic feasibility in enhancing the enzymatic performance of lipase-catalyzed hydrolysis reactions.
    Matched MeSH terms: Enzymes, Immobilized/chemistry; Ionic Liquids/chemistry
  10. Evaluation of in vitro antidiabetic and antioxidant characterizations of Elettaria cardamomum (L.) Maton (Zingiberaceae), Piper cubeba L. f. (Piperaceae), and Plumeria rubra L. (Apocynaceae)
    Ahmed AS, Ahmed Q, Saxena AK, Jamal P
    Pak J Pharm Sci, 2017 Jan;30(1):113-126.
    PMID: 28603121
    Inhibition of intestinal α-amylase and α-glucosidase is an important strategy to regulate diabetes mellitus (DM). Antioxidants from plants are widely regarded in the prevention of diabetes. Fruits of Elettaria cardamomum (L.) Maton (Zingiberaceae) and Piper cubeba L. f. (Piperaceae) and flowers of Plumeria rubra L. (Apocynaceae) are traditionally used to cure DM in different countries. However, the role of these plants has been grossly under reported and is yet to receive proper scientific evaluation with respect to understand their traditional role in the management of diabetes especially as digestive enzymes inhibitors. Hence, methanol and aqueous extracts of the aforementioned plants were evaluated for their in vitro α-glucosidase and α-amylase inhibition at 1 mg/mL and quantification of their antioxidant properties (DPPH, FRAP tests, total phenolic and total flavonoids contents). In vitro optimization studies for the extracts were also performed to enhance in vitro biological activities. The % inhibition of α-glucosidase by the aqueous extracts of the fruits of E. cardamomum, P. cubeba and flowers of P. rubra were 10.41 (0.03), 95.19 (0.01), and -2.92 (0.03), while the methanol extracts exhibited % inhibition 13.73 (0.02), 92.77 (0.01), and -0.98 (0.01), respectively. The % inhibition of α-amylase by the aqueous extracts were 82.99 (0.01), 64.35 (0.01), and 20.28 (0.02), while the methanol extracts displayed % inhibition 39.93 (0.01), 31.06 (0.02), and 39.40 (0.01), respectively. Aqueous extracts displayed good in vitro antidiabetic and antioxidant activities. Moreover, in vitro optimization experiments helped to increase the α-glucosidase inhibitory activity of E. cardamomum. Our findings further justify the traditional claims of these plants as folk medicines to manage diabetes, however, through digestive enzymes inhibition effect.
    Matched MeSH terms: Methanol/chemistry; Antioxidants/chemistry; Biphenyl Compounds/chemistry; Chlorides/chemistry; Ferric Compounds/chemistry; Fruit/chemistry; Hypoglycemic Agents/chemistry; Picrates/chemistry; Plant Extracts/chemistry; Solvents/chemistry; Water/chemistry; Lignans/chemistry; Apocynaceae/chemistry*; Zingiberaceae/chemistry*; Piper/chemistry*; Flowers/chemistry
  11. One-pot synthesis of carbon dots using two different acids and their respective unique photoluminescence property
    Loi E, Ng RW, Chang MM, Fong JF, Ng YH, Ng SM
    Luminescence, 2017 Feb;32(1):114-118.
    PMID: 27166514 DOI: 10.1002/bio.3157
    Carbon dots, a new class of nanomaterial with unique optical property and have great potential in various applications. This work demonstrated the possibility of tuning the emission wavelength of carbon dots by simply changing the acid type used during synthesis. In particular, sulfuric and phosphoric acids and a mixture of the two were used to carbonize the same starting precursor, sucrose. This resulted in the isolation of carbon dots with blue (440 nm) and green (515 nm) emission. Interestingly, the use of an acid mixture at various ratios did not shift the initial emission profile, but did obviously alter the fluorescence efficiency of the peaks. This clearly showed that acid type can be used as an alternative tool to produce carbon dots that have different emissions using the same starting precursor. Copyright © 2016 John Wiley & Sons, Ltd.
    Matched MeSH terms: Carbon/chemistry*; Phosphoric Acids/chemistry*; Sulfuric Acids/chemistry*
  12. Structure identification of a polysaccharide purified from litchi (Litchi chinensis Sonn.) pulp
    Yang B, Prasad KN, Jiang Y
    Carbohydr Polym, 2016 Feb 10;137:570-575.
    PMID: 26686165 DOI: 10.1016/j.carbpol.2015.10.088
    As a health-beneficial fruit, litchi is widely accepted by people in subtropical and tropical regions. However, the critical chemicals responsible for the health benefits are not clear yet. As a large amount of polysaccharides are present in litchi, they might play an important role in the health benefits. In this work, the main water-soluble polysaccharide (LPPBa) was purified from litchi pulp. The chemical structure was characterized as arabinogalactan by gas chromatography and nuclear magnetic resonance spectrometry (NMR). NMR data revealed the glycosidic linkages and their locations in backbone and branches. The precise structure was putatively identified as below, and it was different to those commonly occurred arabinogalactans. The molecular weight was determined to be 2.4 × 10(6)Da by gel permeation chromatography.
    Matched MeSH terms: Plant Extracts/chemistry*; Polysaccharides/chemistry*; Litchi/chemistry*
  13. Synthesis of flexirubin-mediated silver nanoparticles using Chryseobacterium artocarpi CECT 8497 and investigation of its anticancer activity
    Venil CK, Sathishkumar P, Malathi M, Usha R, Jayakumar R, Yusoff ARM, et al.
    Mater Sci Eng C Mater Biol Appl, 2016 Feb;59:228-234.
    PMID: 26652368 DOI: 10.1016/j.msec.2015.10.019
    In this work, the synthesis of silver nanoparticles from a pigment produced by a recently-discovered bacterium, Chryseobacterium artocarpi CECT 8497, was achieved, followed by an investigation of its anticancer properties. The bacterial pigment was identified as flexirubin following NMR ((1)H NMR and (13)C NMR), UV-Vis, and LC-MS analysis. An aqueous silver nitrate solution was treated with isolated flexirubin to produce silver nanoparticles. The synthesised silver nanoparticles were subsequently characterised by UV-Vis spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), X-Ray Diffraction (XRD), and Fourier Transform Infrared (FTIR) Spectroscopy methodologies. Furthermore, the anticancer effects of synthesised silver nanoparticles in a human breast cancer cell line (MCF-7) were evaluated. The tests showed significant cytotoxicity activity of the silver nanoparticles in the cultured cells, with an IC50 value of 36μgmL(-1). This study demonstrates that silver nanoparticles, synthesised from flexirubin from C. artocarpi CECT 8497, may have potential as a novel chemotherapeutic agent.
    Matched MeSH terms: Polyenes/chemistry*; Chryseobacterium/chemistry*; Metal Nanoparticles/chemistry*
  14. Fulltext Thickness Dependent Nanostructural, Morphological, Optical and Impedometric Analyses of Zinc Oxide-Gold Hybrids: Nanoparticle to Thin Film
    Perumal V, Hashim U, Gopinath SC, Haarindraprasad R, Liu WW, Poopalan P, et al.
    PLoS One, 2015;10(12):e0144964.
    PMID: 26694656 DOI: 10.1371/journal.pone.0144964
    The creation of an appropriate thin film is important for the development of novel sensing surfaces, which will ultimately enhance the properties and output of high-performance sensors. In this study, we have fabricated and characterized zinc oxide (ZnO) thin films on silicon substrates, which were hybridized with gold nanoparticles (AuNPs) to obtain ZnO-Aux (x = 10, 20, 30, 40 and 50 nm) hybrid structures with different thicknesses. Nanoscale imaging by field emission scanning electron microscopy revealed increasing film uniformity and coverage with the Au deposition thickness. Transmission electron microscopy analysis indicated that the AuNPs exhibit an increasing average diameter (5-10 nm). The face center cubic Au were found to co-exist with wurtzite ZnO nanostructure. Atomic force microscopy observations revealed that as the Au content increased, the overall crystallite size increased, which was supported by X-ray diffraction measurements. The structural characterizations indicated that the Au on the ZnO crystal lattice exists without any impurities in a preferred orientation (002). When the ZnO thickness increased from 10 to 40 nm, transmittance and an optical bandgap value decreased. Interestingly, with 50 nm thickness, the band gap value was increased, which might be due to the Burstein-Moss effect. Photoluminescence studies revealed that the overall structural defect (green emission) improved significantly as the Au deposition increased. The impedance measurements shows a decreasing value of impedance arc with increasing Au thicknesses (0 to 40 nm). In contrast, the 50 nm AuNP impedance arc shows an increased value compared to lower sputtering thicknesses, which indicated the presence of larger sized AuNPs that form a continuous film, and its ohmic characteristics changed to rectifying characteristics. This improved hybrid thin film (ZnO/Au) is suitable for a wide range of sensing applications.
    Matched MeSH terms: Gold/chemistry*; Zinc Oxide/chemistry*; Metal Nanoparticles/chemistry*
  15. Fulltext Investigation of Embedded Si/C System Exposed to a Hybrid Reaction of Centrifugal-Assisted Thermite Method
    Mahmoodian R, Yahya R, Dabbagh A, Hamdi M, Hassan MA
    PLoS One, 2015;10(12):e0144632.
    PMID: 26641651 DOI: 10.1371/journal.pone.0144632
    A novel method is proposed to study the behavior and phase formation of a Si+C compacted pellet under centrifugal acceleration in a hybrid reaction. Si+C as elemental mixture in the form of a pellet is embedded in a centrifugal tube. The pellet assembly and tube are exposed to the sudden thermal energy of a thermite reaction resulted in a hybrid reaction. The hybrid reaction of thermite and Si+C produced unique phases. X-ray diffraction pattern (XRD) as well as microstructural and elemental analyses are then investigated. XRD pattern showed formation of materials with possible electronic and magnetic properties. The cooling rate and the molten particle viscosity mathematical model of the process are meant to assist in understanding the physical and chemical phenomena took place during and after reaction. The results analysis revealed that up to 85% of materials converted into secondary products as ceramics-matrix composite.
    Matched MeSH terms: Carbon/chemistry*; Ceramics/chemistry*; Silicon/chemistry*
  16. Fulltext The surface structure and thermal properties of novel polymer composite films based on partially phosphorylated poly(vinyl alcohol) with aluminum phosphate
    Mohamed Saat A, Johan MR
    ScientificWorldJournal, 2014;2014:439839.
    PMID: 25506069 DOI: 10.1155/2014/439839
    Partially phosphorylated polyvinyl alcohol (PPVA) with aluminum phosphate (ALPO4) composites was synthesized by solution casting technique to produce (PPVA)(100-y) - (ALPO4)(y) (y = 0, 1, and 2). The surface structure and thermal properties of the films were characterized using Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). The results showed that the films have higher thermal stability with strong bonding between PPVA and ALPO4.
    Matched MeSH terms: Phosphates/chemistry*; Polyvinyl Alcohol/chemistry*; Aluminum Compounds/chemistry*
  17. Trans- and cis-urocanic acid, biogenic amine and amino acid contents in ikan pekasam (fermented fish) produced from Javanese carp (Puntius gonionotus) and black tilapia (Oreochromis mossambicus)
    Ezzat MA, Zare D, Karim R, Ghazali HM
    Food Chem, 2015 Apr 1;172:893-9.
    PMID: 25442635 DOI: 10.1016/j.foodchem.2014.09.158
    Ikan pekasam is a fermented fish product produced in Malaysia and is usually made from freshwater fish with ground roasted uncooked rice as the main source of carbohydrate. In this study, the amino acid, biogenic amine, and trans- and cis-urocanic acid (UCA) contents of fifteen commercial samples of Ikan pekasam made from Javanese carp and black tilapia, that had undergone either natural or acid-assisted fermentation, were quantified. The latter includes either tamarind (Tamarindus indica) pulp or dried slices of Garcinia atroviridis fruit in the fermentation process. Results showed that there are no significant differences in most of the biogenic amines including histamine, while there are significant differences in total UCA content, and trans- and cis-UCA contents between the two samples. Differences in the amino acid contents were largely fish-dependent.
    Matched MeSH terms: Amino Acids/chemistry*; Biogenic Amines/chemistry*; Urocanic Acid/chemistry*
  18. Fulltext New coumarin derivative as an eco-friendly inhibitor of corrosion of mild steel in Acid medium
    Al-Amiery AA, Al-Majedy YK, Kadhum AA, Mohamad AB
    Molecules, 2014 Dec 29;20(1):366-83.
    PMID: 25551187 DOI: 10.3390/molecules20010366
    The anticorrosion ability of a synthesized coumarin, namely 2-(coumarin-4-yloxy)acetohydrazide (EFCI), for mild steel (MS) in 1 M hydrochloric acid solution has been studied using a weight loss method. The effect of temperature on the corrosion rate was investigated, and some thermodynamic parameters were calculated. The results indicated that inhibition efficiencies were enhanced with an increase in concentration of inhibitor and decreased with a rise in temperature. The IE value reaches 94.7% at the highest used concentration of the new eco-friendly inhibitor. The adsorption of inhibitor on MS surface was found to obey a Langmuir adsorption isotherm. Scanning electron microscopy (SEM) was performed on inhibited and uninhibited mild steel samples to characterize the surface. The Density Function theory (DFT) was employed for quantum-chemical calculations such as EHOMO (highest occupied molecular orbital energy), ELUMO (lowest unoccupied molecular orbital energy) and μ (dipole moment), and the obtained results were found to be consistent with the experimental findings. The synthesized inhibitor was characterized by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopic studies.
    Matched MeSH terms: Acids/chemistry*; Coumarins/chemistry*; Steel/chemistry*
  19. Fulltext Artificial neural network modelling of photodegradation in suspension of manganese doped zinc oxide nanoparticles under visible-light irradiation
    Abdollahi Y, Zakaria A, Sairi NA, Matori KA, Masoumi HR, Sadrolhosseini AR, et al.
    ScientificWorldJournal, 2014;2014:726101.
    PMID: 25538962 DOI: 10.1155/2014/726101
    The artificial neural network (ANN) modeling of m-cresol photodegradation was carried out for determination of the optimum and importance values of the effective variables to achieve the maximum efficiency. The photodegradation was carried out in the suspension of synthesized manganese doped ZnO nanoparticles under visible-light irradiation. The input considered effective variables of the photodegradation were irradiation time, pH, photocatalyst amount, and concentration of m-cresol while the efficiency was the only response as output. The performed experiments were designed into three data sets such as training, testing, and validation that were randomly splitted by the software's option. To obtain the optimum topologies, ANN was trained by quick propagation (QP), Incremental Back Propagation (IBP), Batch Back Propagation (BBP), and Levenberg-Marquardt (LM) algorithms for testing data set. The topologies were determined by the indicator of minimized root mean squared error (RMSE) for each algorithm. According to the indicator, the QP-4-8-1, IBP-4-15-1, BBP-4-6-1, and LM-4-10-1 were selected as the optimized topologies. Among the topologies, QP-4-8-1 has presented the minimum RMSE and absolute average deviation as well as maximum R-squared. Therefore, QP-4-8-1 was selected as final model for validation test and navigation of the process. The model was used for determination of the optimum values of the effective variables by a few three-dimensional plots. The optimum points of the variables were confirmed by further validated experiments. Moreover, the model predicted the relative importance of the variables which showed none of them was neglectable in this work.
    Matched MeSH terms: Cresols/chemistry*; Manganese/chemistry*; Zinc Oxide/chemistry*
  20. Highly sensitive silicon nanowire biosensor with novel liquid gate control for detection of specific single-stranded DNA molecules
    Adam T, Hashim U
    Biosens Bioelectron, 2015 May 15;67:656-61.
    PMID: 25453738 DOI: 10.1016/j.bios.2014.10.005
    The study demonstrates the development of a liquid-based gate-control silicon nanowire biosensor for detection of specific single-stranded DNA (ssDNA) molecules. The sensor was fabricated using conventional photolithography coupled with an inductively coupled plasma dry etching process. Prior to the application of DNA to the device, its linear response to pH was confirmed by serial dilution from pH 2 to pH 14. Then, the sensor surface was silanized and directly aminated with (3-aminopropyl) triethoxysilane to create a molecular binding chemistry for biofunctionalization. The resulting Si‒O‒Si‒ components were functionalized with receptor ssDNA, which interacted with the targeted ssDNA to create a field across the silicon nanowire and increase the current. The sensor shows selectivity for the target ssDNA in a linear range from target ssDNA concentrations of 100 pM to 25 nM. With its excellent detection capabilities, this sensor platform is promising for detection of specific biomarkers and other targeted proteins.
    Matched MeSH terms: DNA, Single-Stranded/chemistry; Silicon/chemistry; Nanowires/chemistry*
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links