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Production of green biofuel by using a goat manure supported Ni–Al hydrotalcite catalysed deoxygenation process
No full textThe high oxygen content in natural biomass resources, such as vegetable oil or biomass-pyrolysed bio oil, is the main constraint in their implementation as a full-scale biofuel for the automotive industry. In the present study, renewable fuel with petrodiesel-like properties was produced via catalytic deoxygenation of oleic acid in the absence of hydrogen (H 2 ). The deoxygenation pathway of oleic acid to bio-hydrocarbon involves decarboxylation/decarbonylation of the oxygen content from the fatty acid structure in the form of carbon dioxide (CO 2 )/carbon monoxide (CO), with the presence of a goat manure supported Ni-Al hydrotalcite (Gm/Ni-Al) catalyst. Goat manure is an abundant bio-waste, containing a high mineral content, urea as well as cellulosic fiber of plants, which is potentially converted into activated carbon. Synthesis of Gm/Ni-Al was carried out by incorporation of pre-activated goat manure (GmA) during co-precipitation of Ni-Al catalyst with 1 : 3, 1 : 1 and 3 : 1 ratios. The physico-chemical properties of the catalysts were characterized by X-ray diffractometry (XRD), Brunauer-Emmet-Teller (BET) surface area, field emission surface electron microscopy (FESEM) and temperature program desorption ammonia (TPD-NH 3 ) analysers. The catalytic deoxygenation reaction was performed in a batch reactor and the product obtained was characterized by using gas chromatography-mass spectroscopy (GCMS) for compound composition identification as well as gas chromatography-flame ionisation detector (GC-FID) for yield and selectivity determination. The optimization and evaluation were executed using response surface methodology (RSM) in conjunction with central composite design (CCD) with 5-level-3-factors. From the RSM reaction model, it was found that the Gm/Ni-Al 1 : 1 catalysed deoxygenation reaction gives the optimum product yield of 97.9% of hydrocarbon in the range of C 8 -C 20 , with diesel selectivity (C 17 : heptadecane and heptadecene compounds) of 63.7% at the optimal reaction conditions of: (1) reaction temperature: 327.14 °C, (2) reaction time: 1 h, and (3) catalyst amount: 5 wt%
Space Science Education in Malaysia: A review based on performance improvement framework in complex systems
No full textThis paper focused on reviewing space science education in Malaysia based on the performance improvement framework in complex systems. Therefore, not all articles were reviewed but only randomly selected ones to find the pattern by analyzing activities commenced and compared to the performance improvement framework in complex systems. The data were then analyzed by using the continuous comparison method. The findings from this study implied that to improve space science education for the younger generation, it was important to view the direction of education and to understand in depth the complex systems of education as a whole. The direction of the younger generation's education system should enable them to solve complex problems efficiently. Space science education could be set as an example of how to move forward in this direction. This is due to the nature of space science education itself which is multidisciplinary. Transdisciplinary methods could be used in space science education and might act as a case of an integrated STEM model for the Malaysian Education System. Other implications of the transdisciplinary method implementation are exposure to systems thinking among scientists, teachers, educators, administrators, authorities, students and the public. The changes will take effect only if more people are aware of the importance of systems thinking as the basis in life so as to be able to understand that all the elements are interconnected in the complex systems as a whole
Digital Matched Filtering (DMF) Technique for the Performance Enhancement of Few-Mode Fiber Bragg Grating Sensor
No full textIn this paper, the digital matched filtering (DMF), a signal processing technique, has been proposed to identify the multiple peak wavelengths more accurately from the reflection spectra of etched few-mode fiber Bragg grating (FM-FBG) sensor. The etched FM-FBG has been fabricated and its intrinsic property of having different sensitivities for different reflection peaks in the spectrum has been used for sensing the multiple parameters, such as temperature and refractive index of the ambient environment. The experimental characterization of the fabricated etched FM-FBG sensor has been carried out by using six samples of standard sodium chloride (NaCl(aq)) solutions with refractive indices (RIs) ranging from 1.3159 to 1.3375 at 24 °C temperature. The reflection spectra have been acquired for each sample by varying the temperature from 24 °C to 80 °C. The temperature and RI sensitivities have been investigated from the acquired spectra by using DMF. The obtained sensor results have been compared with conventional peak detection (CPD) method results for the same spectra. It has been observed that the results obtained by the DMF technique are closer to the reference sensor values and has shown more accuracy than the results obtained by the CPD technique. It has been shown that the DMF has better performance in terms of the accuracy of measured results than that of CPD. In addition, to eliminate the effect of the cross-sensitivity issue of the sensor, the 3 × 3 order characteristic matrix has been used. Hence, the etched FM-FBG can be used as multi-parameter measurements with better performance using the DMF technique
Surface modification of Ti64-Alloy with silver silicon nitride thin films
No full textTi6Al4V (Ti64) alloys is an alpha-beta titanium alloy with good corrosion resistance, high strength-to-weight ratio, excellent physiochemical stability and good biocompatibility. However, Ti64 alloy loses its biocompatibility when it is introduced into human tissues due to possible toxic of Vanadium (V) and Aluminum (Al) ion release. Thus, modification using silver silicon nitride films onto Ti64 via magnetron sputtering technique was proposed. In this study, a set of experimental depositing AgSiN films on Ti64 alloys using different bias voltage (0, −75, −150 and −200 V) were fabricated. The surface characterization and mechanical performance of the thin films with respect to bias voltage were studied using scanning electron microscope (SEM), atomic force microscope (AFM), X-ray diffraction (XRD), nanoindentation and scratch test. Meanwhile, the biological function of the films was tested through wettability and antibacterial tests. According to the results, all thin films showed similar morphology with the highest adhesion strength (596 mN) was obtained for AgSiN thin film deposited at −75 V. The hardness (5.5 GPa) and elastic modulus (211.0 GPa) of sample deposited at −150 V showed an improvement for about 50% compared to the Ti64 substrate (H = 2.75, E = 113.8). The lowest compressive residual stress 0.06 GPa was noted for samples that have highest adhesion strength and highest thickness. In terms of biological functionality, all films showed hydrophilic property with wetting angle observed were below 90°. An inhibition zone area that observed on Bulkholderia pseudomallei (B.Psudomallei) and Escherichia coli (E.coli) were 7 and 10 mm respectively, which proved the AgSiN films as a promising candidate to be used in antibacterial applications
Logo Hari Kebangsaan 2018: Analisis Teori Seni dan Aplikasi Komunikasi Visual (Malaysian National Day Logo 2018: An Analysis Based on the Theory of Arts and Visual Communication)
No full textA logo is an important tool for visual communication especially for promotional activity, brand identity and campaigns. It is also an important means to disseminate public information. Additionally, a logo is normally used in creating and representing the corporate image for an event or entity. As a coat of arms for a country, a logo is embedded with deep meaning depicted through various elements on a heraldic visual design. Meanings of a logo can be associated with the local sociocultural context it represents as every design element of a logo has its own significant message or value. This research analyses the logo for the 2018 Independence Day for Malaysia by focusing on the design and the application on the medium it is based on. Every element used in the design is analysed according to art and design elements and principals which includes line, form, colour-tone, space, balance, contrast and pattern. The logo is also analysed based on visual communication theory. This research shows that the structure and design management (which includes colour element and design principles) of the 2018 Independence Day logo is imperfect and has affected the ideal function of a logo as a visual communication tool. Suggestions for futher improvements which will not change the main structure and meaning of the logo design are enclosed in this paper
Process intensification of cellulase and bioethanol production from sugarcane bagasse via an integrated saccharification and fermentation process
No full textThe production of value-added products such as cellulase and ethanol via a consolidated bioprocess could be realized by tapping into the multiple actions of a microbial community. For this purpose, an in situ saccharification and fermentation process through a sequential co-culture white-rot fungus and Saccharomyces cerevisiae on NaOH-pretreated sugarcane bagasse (SCB) was investigated. In the present work, white rot fungus plays a role in the production of cellulase enzymes. With the produced cellulase, an in situ saccharification process took place in the reactor to depolymerize pretreated SCB into reducing sugar. The reducing sugar was converted into ethanol via fermentation by S. cerevisiae, which was added into the system sequentially. White rot fungus Pycnoporus sanguineus was selected due to its competency in producing cellulase and reducing sugar production. The operating condition to maximize the production of reducing sugar in situ was obtained through a Central Composite Design method. A total of 3.13 g reducing sugar/100 g SCB was obtained when P. sanguineus was cultivated at 0.6% inoculum loading, 70% moisture content and 4 days. Subsequently, 4.5 g ethanol/100 g SCB was obtained from the in situ saccharification and fermentation system after S. cerevisiae was sequentially inoculated
Novel natural rubber-based epoxy coating
No full textThe use of renewable resources in development of polymeric products is becoming more relevant in the current times, braced by the scarcity of fossil resources and threat from global warming. The manuscript describes the preparation of epoxy resin from epoxidized natural rubber (ENR) via ultraviolet (UV) treatment, followed by investigation on the film properties of the coating produced by blending the natural rubber-based epoxy resin with pentaerythritol tetrakis(3-mercaptopropionate), PETMP as the hardener. The UV treatment involved is responsible to break down the natural rubber into smaller molecular weight fractions so that it becomes more compatible with common solvents and chemicals, and at the same time improves the solubility and viscosity of the resin. The results obtained are very encouraging, with significant reduction in the molecular weight of the rubber observed after 6 hours of UV treatment, and spectroscopic characterization suggests that substantial amount of epoxide group in the ENR was effectively preserved during the treatment for subsequent reaction with PETMP. The epoxide group in the UV-degraded ENR was found to react with the –SH group of PETMP after the two were blended, applied into film, and heated at 80 °C. The properties of the coatings produced were investigated via pencil hardness test, crosshatch adhesion tape test, thermal stability test, water, and chemical resistance test. Most of the coating formulations produced film with excellent hardness, adhesion and chemical resistance. Coating B and C are among the best coating formulations, with both recorded pencil hardness grade ≥ 4H, zero film removal in the adhesion test, no film defect observed during saltwater, acid and alkaline resistance test, and reasonably good thermal stability with onset of degradation above 200 °C
In vivo administration of quercetin ameliorates sperm oxidative stress, inflammation, preserves sperm morphology and functions in streptozotocin-nicotinamide induced adult male diabetic rats
No full textIntroduction: Diabetes mellitus (DM) has been associated with sperm damage. In view of the fact that quercetin possesses antioxidant and anti-inflammatory activities, this compound may help to protect sperm against damage in DM. In this study, in-vivo effects of quercetin on sperm parameters in DM were investigated. Material and methods: Quercetin (10, 25 and 50 mg/kg/b.w.) was given orally to streptozotocin-nicotinamide induced adult male diabetic rats for 28 days. Following treatment completion, rats were sacrificed and sperm were harvested from the cauda epididymis. Sperm count, motility, viability, hyperosmotic swelling (HOS) tail-coiled sperm and morphology were assessed. Levels of lipid peroxidation (LPO) and anti-oxidative enzymes (SOD, CAT and GPx) in sperm with and without H 2 O 2 incubation were determined by biochemical assays. Expression levels of SOD, CAT and GPx mRNAs in sperm were evaluated by qPCR. Sperm DNA integrity was estimated by flow cytometry while expression levels of the inflammatory markers NF-κβ and TNF-α in sperm were determined by Western blotting. Results: In diabetic rats receiving quercetin, sperm count and motility, viability and HOS tail-coiled sperm increased (p < 0.05) while sperm with abnormal morphology decreased. Moreover, sperm SOD, CAT, GPx activities and their mRNA expression levels increased while sperm LPO, NF-κβ and TNF-α levels decreased. In normal and diabetic rat sperm incubated with H 2 O 2 , a further increase in MDA and further decreases in SOD, CAT and GPx were observed, and these were ameliorated by quercetin treatment. Conclusions: In-vivo administration of quercetin to diabetic rats helps to ameliorate sperm damage and improves sperm morphology and functions in DM
Synergistic Growth Inhibition by Afatinib and Trametinib in Preclinical Oral Squamous Cell Carcinoma Models
No full textBackground: Given that aberrant activation of epidermal growth factor receptor family receptors (ErbB) is a common event in oral squamous cell carcinoma, and that high expression of these receptor proteins is often associated with poor prognosis, this rationalizes the approach of targeting ErbB signaling pathways to improve the survival of patients with oral squamous cell carcinoma. However, monotherapy with the ErbB blocker afatinib has shown limited survival benefits. Objectives: This study was performed to identify mechanisms of afatinib resistance and to explore potential afatinib-based combination treatments with other targeted inhibitors in oral squamous cell carcinoma. Methods: We determined the anti-proliferative effects of afatinib on a panel of oral squamous cell carcinoma cell lines using a crystal violet-growth inhibition assay, click-iT 5-ethynyl-2′-deoxyuridine staining, and cell-cycle analysis. Biochemical assays were performed to study the underlying mechanism of drug treatment as a single agent or in combination with the MEK inhibitor trametinib. We further evaluated and compared the anti-tumor effects of single agent and combined treatment by using oral squamous cell carcinoma xenograft models. Results: In this study, we showed that afatinib inhibited oral squamous cell carcinoma cell proliferation via cell-cycle arrest at the G0/G1 phase, and inhibited tumor growth in xenograft mouse models. Interestingly, we demonstrated reactivation of the mitogen-activated protein kinase (ERK1/2) pathway in vitro, which possibly reduced the effects of ErbB inhibition. Concomitant treatment of oral squamous cell carcinoma cells with afatinib and trametinib synergized the anti-tumor effects in oral squamous cell carcinoma-bearing mouse models. Conclusions: Our findings provide insight into the molecular mechanism of resistance to afatinib and support further clinical evaluation into the combination of afatinib and MEK inhibition in the treatment of oral squamous cell carcinoma. © 2019, Springer Nature Switzerland AG
Large-scale structure formation in ionic solution and its role in electrolysis and conductivity
No full textThat water may not be an inert medium was indicated by the presence at water’s interfaces a negatively charged solute free zone of several hundred microns in thickness called the exclusion zone (EZ). Further evidence was demonstrated by Ovchinnikova’s experiments (2009) showing that water can store and release substantial amount of charge. We demonstrate that the charge storage capacity of water arises from highly stable large-scale ionic structures with measurable charge imbalances and discrete levels of charge density. We also show evidence that the charge zones formation requires ionic solutes, and their formation correlate to large change in conductivity, by as much as 250%. Our experiments indicate that large-scale structuring plays a pivotal role in electrolysis and conductivity in ionic solution. We propose that water is an electrochemically active medium and present a new model of electrolysis and conductivity in ionic solution. © 2019 Yee et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited