Displaying publications 61 - 80 of 442 in total

Abstract:
Sort:
  1. Fulltext Bio-asphalt concrete: From waste product to green aggregate replacement
    Resdiansyah, Amidah Mohd Ujang, Zarinah Zaini
    Pertanika Journal of Science & Technology, 2017;25(105):145-154.
    MyJurnal
    Malaysia has over 5 million hectares of land planted with palm oil, divided almost equally between peninsula Malaysia and East Malaysia. This paper presents a laboratory evaluation of the performance of the waste product palm kernel shell (PKS) in creating plant-based asphalt concrete (bio-asphalt concrete). PKS aggregate partially replaced granite aggregate in preparing the mixes (10%, 30%, and 100%) in the range of 5mm-14mm in ACW 14 mixed with 5% to 7% of bitumen content. 35 blows and 50 blows compaction of mixes was used to evaluate the potential of palm kernel shells in the preparation of bitumen to deal with light to medium traffic. Results showed that PKS aggregate can be used up to 30% PKS replacement for the light traffic design and only 10% PKS replacement was potential to be used in medium traffic design.
    Matched MeSH terms: Silicon Dioxide
  2. Grafting Behavior for the Resonating Variants of Ethynylaniline on Hydrogenated Silicon (100) Surfaces under Thermal Hydrosilylation
    Tung J, Tew LS, Coluccini C, Lin YD, Khung YL
    Chemistry, 2018 Jun 22.
    PMID: 29932257 DOI: 10.1002/chem.201802003
    This work reports the outcome of thermal grafting of 2-ethynylaniline, 3-ethynylaniline, and 4-ethynylaniline on a hydrogenated Si(100) surface. Using high-resolution XPS and AFM, it was found that the grafting of these compounds could be attributed to resonating structures that arise from the position of an electron-donating NH2 group and an electron-withdrawing acetylene group. For the ortho- and para-positioned acetylene group, surface reactions were observed to proceed predominantly via the acetylene to form a Si-C bond, whereas the meta-positioned acetylene group was found to have undergone nucleophilic grafting through the NH2 group onto the silicon surface to form a Si-N bond. Furthermore, a tert-butoxycarbonyl-protected derivative for a meta-positioned ethynylaniline was synthesized to exclusively force the reaction to react with the acetylene group and subsequent analysis confirmed that unprotected 3-ethynylaniline had indeed reacted through the nucleophilic NH2 group as hypothesized. Thus, for the first time, the interplay between resonance structures and their effects on silicon surface modifications were systematically catalogued.
    Matched MeSH terms: Silicon
  3. Altering fiber density of cockscomb-like fibrous silica-titania catalysts for enhanced photodegradation of ibuprofen
    Fauzi AA, Jalil AA, Mohamed M, Triwahyono S, Jusoh NWC, Rahman AFA, et al.
    J Environ Manage, 2018 Dec 01;227:34-43.
    PMID: 30172157 DOI: 10.1016/j.jenvman.2018.08.073
    Fibrous silica-titania (FST) catalysts were synthesized by microemulsion followed by silica seed-crystal crystallization methods under various molar ratios of toluene to water (T/W). The catalysts were characterized by XRD, UV-DRS, FESEM, TEM, AFM, N2 adsorption-desorption, FTIR, and ESR. The results revealed that altering the T/W ratio affected the growth of the silica and titania and led to different size, fiber density, silica-titania structure, and number of hydroxyl groups, as well as oxygen vacancies in the FSTs, which altered their behavior toward subsequent application. Photodegradation of ibuprofen (IBP) are in the following order: FST(6:1) (90%) > FST(5:1) (84%) > FST(7:1) (79%) > commercial TiO2 (67%). A kinetics study using Langmuir-Hinshelwood model illustrated that the photodegradation followed the pseudo-first-order and adsorption was the rate-limiting step. Optimization by response surface methodology (RSM) showed that the pH, initial concentration, and catalyst dosage were the remarkable parameters in photodegradation of IBP. The FST (6:1) maintained its photocatalytic activities for up to five cycles reaction without serious catalyst deactivation, and was also able to degrade other endocrine-disrupting chemicals, indicating its potential use for the treatment of those chemicals in wastewater.
    Matched MeSH terms: Silicon Dioxide
  4. Fulltext Evaluation of the Properties, Gas Permeability, and Selectivity of Mixed Matrix Membrane Based on Polysulfone Polymer Matrix Incorporated with KIT-6 Silica
    Ding SH, Ng TYS, Chew TL, Oh PC, Ahmad AL, Ho CD
    Polymers (Basel), 2019 Oct 23;11(11).
    PMID: 31652828 DOI: 10.3390/polym11111732
    Mixed matrix membranes (MMMs) separation is a promising technology for gas permeation and separation involving carbon dioxide (CO2). However, finding a suitable type of filler for the formation of defect-free MMMs with enhancement in gas permeability remains a challenge. Current study focuses on synthesis of KIT-6 silica and followed by the incorporation of KIT-6 silica as filler into polysulfone (PSF) polymer matrix to fabricate MMMs, with filler loadings of 0-8 wt %. The effect of KIT-6 incorporation on the properties of the fabricated MMMs was evaluated via different characterization techniques. The MMMs were investigated for gas permeability and selectivity with pressure difference of 5 bar at 25 °C. KIT-6 with typical rock-like morphology was synthesized. Incorporation of 2 wt % of KIT-6 into PSF matrix produced MMMs with no void. When KIT-6 loadings in the MMMs were increased from 0 to 2 wt %, the CO2 permeability increased by ~48%, whereas the ideal CO2/CH4 selectivity remained almost constant. However, when the KIT-6 loading in PSF polymer matrix was more than 2 wt %, the formation of voids in the MMMs increased the CO2 permeability but sacrificed the ideal CO2/CH4 selectivity. In current study, KIT-6 was found to be potential filler for PSF matrix under controlled KIT-6 loading for gas permeation.
    Matched MeSH terms: Silicon Dioxide
  5. Comparison analysis on scaling the vertical and lateral NMOSFET in nanometer regime
    Ismail Saad, Razali Ismail, Ima Sulaiman
    Sains Malaysiana, 2008;37:233-237.
    Conventional lateral and vertical n-channel MOS transistors with channel length in the range of 100nm to 50nm have been systematically investigated by means of device simulation. The comparison analysis includes critical parameters that govern device performance. Threshold voltage VT roll-off, leakage current Ioff, drain saturation current IDsat and sub-threshold swing S were analyze and compared between the device. Due to double gate (DG) structure over the side of silicon pillar a better electrostatics potential control of channel is obtained in vertical device shown by an analysis on VT roll-off. A two decade higher of Ioff in planar device is observed with Lg=50nm. A factor of three times larger IDsat is observed for vertical MOSFETs compared to planar device. The sub-threshold swing S remains almost the same when the Lg larger than 80 nm. It increased rapidly when the Lg is scaled down to 50 nm due to the short channel effect SCE. However, the vertical device has a steady increase whereas the planar device has suffered immediate enhance of SCE. The analysis results confirmed that vertical MOSFET with double-gate structure is a potential solution to overcome SCE when scaled the channel length to 50nm and beyond.
    Matched MeSH terms: Silicon
  6. Optimization of fluorescent silicon nanomaterial production using peroxide/acid/salt technique
    Abu Hassan LH
    Sains Malaysiana, 2009;38.
    Silicon nanomaterial was prepared using the peroxide/acid/salt technique in which an aqueous silicon-based salt solution was added to H2O2/HF etchants. In order to optimize the experimental conditions for silicon nanomaterial production, the amount of nanomaterial produced was studied as a function of the volume of the silicon salt solution used in the synthesis. A set of samples was prepared using: 0, 5, 10, 15, and 20 mL of an aqueous 1 mg/L metasilicate solution. The area under the corresponding peaks in the infrared (ir) absorption spectra was used as a qualitative indicator to the amount of the nanomaterial present. The results indicated that using 10 mL of the metasilicate solution produced the highest amount of nanomaterial. Furthermore, the results demonstrated that the peroxide/acid/salt technique results in the enhancement of the production yield of silicon nanomaterial at a reduced power demand and with a higher material to void ratio. A model in which the silicon salt forms a secondary source of silicon nanomaterial is proposed. The auxiliary nanomaterial is deposited into the porous network causing an increase in the amount of nanomaterial produced and a reduction in the voids present. Thus a reduction in the resistance of the porous layer, and consequently reduction in the power required, are expected.
    Matched MeSH terms: Silicon
  7. Konglomerat di Jalur Timur: Hubungan Genetik di antara Konglomerat Murau, Pulau Redang, Pulau Kapas dan Bukit Keluang
    Che Aziz Ali, Kamal Roslan Mohamed
    Sains Malaysiana, 1997;26.
    Conglomerates of continental origin are widely distributed in the Eastern Belt of the Malay Peninsular. Murau Conglomerate is the best example. Similar deposits outcrop at Pulau Redang, Pulau Kapas and Bukit Keluang. With an exception of Pulau Redang Conglomerate, similarities in lithologic, sedimentologic and stratigraphic characters of these conglomerates suggested that they can be combined into one group. Their stratigraphic position that is overlying the Upper Paleozoic unconformities reveals that these rock units are representing the basal part of the continental sediments that are found in the Eastern Belt. The sediments have been deposited as early as in the Late Permain and the deposition continued until Triassic. This interpretation is based on the occurrence of the Upper Paleozoic unconformities in the Eastern Belt and also on the age of sediments beneath the unconformities at Pulau Redang. The uplift that gives rise to this unconformity may be attributed to the granite emplacement in the Eastern Belt in the Late Permian-Early Triassic time. This was followed by depositions of the basal conglomerate mentioned above. The basal conglomerates were then overlain by fined grained sediments which are represented by Panti Sandstone, Lotong Sandstone and other equivalent deposits of Jurassic Cretaceous age.
    Konglomerat endapan benua banyak tertabur di lalur Timur Semenanjung Malaysia. Konglomerat Murau adalah satu contoh yang terbaik. Konglomerat yang mempunyai, ciri-ciri yang sama terdapat di beberapa lokaliti di Pulau Redang, Pulau Kapas dan Bukit Keluang. Ciri-ciri litologi sedimentologi dan stratigrafi kesemua konglomerat ini mencadangkan bahawa mereka boleh dikumpulkan di dalam satu kumpulan yang. sama kecuali Konglomerat Pulau Redang. Kedudukannya langsung di atas satah ketakselarasan Paleozoik Atas mencadang unit-unit konglomerat ini merupakan bahagian dasar kepada sedimen kebenuaan yang terdapat di Jalur Timur dan mungkin juga di jalur Tengah. Sedimen ini mula terendap semenjak Perm Akhir hingga Trias berdasarkan ketakselarasan yang terdapat di Jalur Timur dan juga usia sedimen di bawah satah ketakselarasan yang terdapat di Pulau Redang. Pengangkatan yang berkaitan mungkin terhasil daripada perejahan granit di Jalur Timur semasa Perm Akhir-Trias Awal. Pengangkatan ini diikuti oleh pemendapan konglomerat dasar yang disebut di atas. Pengenapan seterusnya diikuti oleh sedimen berbutir lebih halus yang menindihnya yang diwakili oleh Batu Pasir Panti, Batu Pasir Lotong dan yang lain-lain yang setara dengannya yang mungkin berusia Jura-Kapur.
    Matched MeSH terms: Silicon Dioxide
  8. Potential alkali-reactivity of granite aggregates in the Bukit Lagong area, Selangor, peninsular Malaysia
    Ng TF, Raj JK, Ghani AA
    Sains Malaysiana, 2013;42:773-781.
    The Bukit Lagong area is the most important aggregate supply centre in Selangor. Geological studies were carried out in four quarries in the Bukit Lagong area and samples were subjected to petrographic examination and accelerated expansion tests to assess the potential alkali-aggregate reactivity of granite aggregates. The granitic rocks comprise mainly of coarse grained megacrystic granite, minor medium grained megacrystic granite and microgranite. Petrographic examination showed that the primary minerals in these undeformed granitic rocks are not alkali reactive. Faulting and related alteration and mineralization have produced potentially alkali reactive minerals including microcrystalline and strained quartz and fine phyllosilicates. Marginally deleterious and deleterious expansion is shown by the accelerated mortar bar tests. Although alkali reactive rocks are present in some quarries in Bukit Lagong, their volume is small. When blended with the undeformed granitic rocks, the aggregates produced are not expected to cause alkali-aggregate reaction in concrete.
    Matched MeSH terms: Silicon Dioxide
  9. Current and conductance modulation at elevated temperature in siliconand InAs-based spin field-effect transistors
    Osintsev D, Sverdlov V, Makarov A, Selberherr S
    Sains Malaysiana, 2013;42:205-211.
    Spin field-effect transistors (SpinFETs) are promising candidates for future integrated microelectronic circuits. A SpinFET is composed of two ferromagnetic contacts (source and drain), which sandwich a semiconductor channel. Current modulation is achieved by electrically tuning the gate voltage dependent strength of the spin-orbit interaction in the semiconductor region. We investigated the properties of SpinFETs for various parameters - the band mismatch, the barrier height between the contacts and the channel and the strength of the spin-orbit coupling, for various temperatures. We demonstrated that the creation of Schottky barriers between the channel and the contacts guarantees a pronounced modulation of the magnetoresistance sufficient to open a possibility to operate SpinFETs at room temperature. We also demonstrated that silicon fins with [100] orientation exhibit a stronger dependence on the value of the spin-orbit interaction and are thus preferable for practical realization of silicon-based SpinFETs.
    Matched MeSH terms: Silicon
  10. Application of spectral analysis of surface waves (SASW) method: rock mass characterization
    Goh T, Abdul Rahim Samsudin, Abdul Ghani Rafek
    Sains Malaysiana, 2011;40.
    A geotechnical study needs to be carried out to determine the engineering parameters of the rock mass at the project site in executing construction projects such as tunnels, dams, highways and buildings. Design and safety factor of the construction are highly dependent on soil and rock engineering parameters which are usually determined by in-situ test such as Standard Penetration Test (SPT) and seismic tests. The SPT test which normally involves drilling and laboratory works always incur high operating cost, while seismic tests on the other hand are fast, cheap, non-destructive and an easy to operate method for rock mass characterization. The spectral analysis of surface waves (SASW) method is an in situ and non-destructive measurement that is rapid and cost effective. The aims of this study were to determine Rock Quality Designation (RQD) value, excavation classification analysis as well as site characterization by using the SASW method. WinSASW 3.1.3 was used for inversion processing of the SASW data to produce shear wave velocity (Vs) versus depth profiles. The profiles were then analyzed and correlated with rock mass engineering geological parameters such as RQD and site characterization as well as excavation classification of rock mass. Twenty (20) SASW tests were conducted on the granitic rock mass and four (4) SASW tests were conducted on a cut hill slope of metasedimentary rocks. RQD values were computed based on shear wave velocities and ultrasonic velocities of intact (fresh) rock. The differences between RQD obtained from SASW method and those from discontinuity survey were found to be less than 10%. Excavation classification for granitic rock mass at JKR Quarry was empirically determined using both SASW and ultrasonic velocities as well as RQD value of the rock mass. Site characterization for metasedimentary rocks mass at Bukit Tampoi was determined based on shear wave velocities from SASW method.
    Matched MeSH terms: Silicon Dioxide
  11. Fulltext Fabrication of Si Micropore and Graphene Nanohole Structures by Focused Ion Beam
    Md Ibrahim NNN, Hashim AM
    Sensors (Basel), 2020 Mar 12;20(6).
    PMID: 32178225 DOI: 10.3390/s20061572
    A biosensor formed by a combination of silicon (Si) micropore and graphene nanohole technology is expected to act as a promising device structure to interrogate single molecule biopolymers, such as deoxyribonucleic acid (DNA). This paper reports a novel technique of using a focused ion beam (FIB) as a tool for direct fabrication of both conical-shaped micropore in Si3N4/Si and a nanohole in graphene to act as a fluidic channel and sensing membrane, respectively. The thinning of thick Si substrate down to 50 µm has been performed prior to a multi-step milling of the conical-shaped micropore with final pore size of 3 µm. A transfer of graphene onto the fabricated conical-shaped micropore with little or no defect was successfully achieved using a newly developed all-dry transfer method. A circular shape graphene nanohole with diameter of about 30 nm was successfully obtained at beam exposure time of 0.1 s. This study opens a breakthrough in fabricating an integrated graphene nanohole and conical-shaped Si micropore structure for biosensor applications.
    Matched MeSH terms: Silicon/chemistry*; Silicon Compounds/chemistry
  12. Lead adsorption behaviours on nanoscale zero valent irons (nZVI) coupled with rice husk MCM-41
    Kaewbuddee C, Chanpiwat P, Kidkhunthod P, Wantala K
    Sains Malaysiana, 2016;45:1155-1167.
    The aims of this work were to investigate the characteristics of nanoscale zero valent irons (nZVI) coupled with mesoporous
    materials (RH-MCM-41) adsorbent and to study the removal mechanisms of Pb (II) from synthetical solutions using full
    pictorial design batch experiments. Synthetic nZVI coupled with RH MCM-41 as Pb (II) adsorbent were characterized
    by XRD, TEM, BET and XANES. The results of XANES analyses confirmed the ability of RH-MCM-41 to prevent oxidations of
    Fe0
    to Fe2+ and Fe3+. XANES results also verified the oxidation states of Pb (II). The solution pH was the most significant
    positive effect in controlling Pb (II) adsorption. The equilibrium and kinetic adsorption isotherms well fitted with the
    Langmuir isotherm. The pseudo-second order kinetic adsorption indicated that the adsorption process is the rate limiting
    step for Pb (II) removal. Furthermore, Langmuir-Hinshelwood confirmed the obvious Pb (II) adsorption at the active
    site of adsorbents. The reduction rate constant (kr
    = 5,000 mg/L.min) was higher than the adsorption rate constant (Kad
    = 0.0002 L/mg). Regarding the research results, four pathways including: reduction process, adsorption on FeOOH,
    adsorption on RH-MCM-41 and complex reaction between Fe and Pb ions were suggested for Pb (II) removal by nZVI
    coupled with RH-MCM-41.
    Matched MeSH terms: Silicon Dioxide
  13. Assessment of ultimate bearing capacity based on the hoek-brown failure criterion
    Lai OT, Md. Selim Reza, Abdul Ghani Rafek, Ailie Sofyiana Serasa, Azimah Hussin, Ern LK
    Sains Malaysiana, 2016;45:1603-1607.
    The ultimate bearing capacity is an essential requirement in design quantification for shallow foundations especially
    for structures built on large rock masses. In many engineering projects, structures built on foundation of heavily jointed
    rock masses may face issues such as instability and sudden catastrophic rock slope failure. Determination of the ultimate
    bearing capacity (Qult) of foundations resting on rock mass has traditionally been determined by employing several
    strength criterions. One of the accepted and widely implemented methods is to use the Hoek-Brown failure criterion 2002,
    where the required parameters are determined from a rock mass classification system, Geological Strength Index (GSI).
    This paper defines an assessment for ultimate bearing capacity (Qult) based on the Hoek-Brown failure criterion 2002
    for a granitic rock slope beneath a 20 m diameter concrete water tank at Bandar Mahkota Cheras, Kajang, Selangor.
    Based on the Hoek-Brown failure criterion 2002, the ultimate bearing capacity (Qult) of rock mass was 7.91 MPa. The
    actual stress acting on the rock mass was 0.32 MPa. The assessment showed that the rock mass is safe since the ultimate
    bearing capacity (Qult) is 24.7 times higher than the actual stress acting on the rock mass.
    Matched MeSH terms: Silicon Dioxide
  14. Compressibility characteristics of compacted clay treated with cement, peat ash and silica sand
    Mousavi S, Leong SW
    Sains Malaysiana, 2017;46:97-106.
    This paper investigates the compressibility characteristics of compacted clay treated with cement, peat ash and silica
    sand. For this purpose, one dimensional consolidation tests were conducted to determine the soil consolidation properties.
    The test specimens were trimmed from the compaction test specimen. The 1D consolidation test specimen was subjected
    to the normal pressures of 2.5, 5, 10, 20, 40, 80 and 160 kPa in sequence on the test specimen which was saturated with
    distilled water. At the end of the loading period of 80 kPa, the vertical load was removed and the specimen was allowed
    to expand for 24 h for the purpose of evaluating of its swelling behavior. The results showed that void ratio of the soil
    specimens decreased with increasing effective normal pressure. The laboratory investigation clearly demonstrates that,
    settlement is as the compression of a soil specimen due to vertical loading applied at the top surface of the 1D consolidation
    test specimen. It was concluded that, the compression settlement of the stabilized soil with the binder composition of
    18% cement, 2% peat ash and 5% silica sand improved by almost 1.3-fold. A notable discovery is the suitability of the
    stabilized soil for road embankment and low lying marginal area for foundation works; also solving the environmental
    problems in relation to peaty ground. However, sufficient laboratory and field testing are required.
    Matched MeSH terms: Silicon Dioxide
  15. Combination of gamma irradiation and sodium carbonate pretreatment on oil palm empty fruit bunch (efb) for high acidic hydrolysis yield
    Siew XC, Chin HC, Sarani Zakaria, Sahrim Ahmad, Siti Masrinda Tasirin
    Sains Malaysiana, 2017;46:167-173.
    Oil palm empty fruit bunch (EFB) fibres were pretreated by gamma irradiation followed by sodium carbonate (Na2
    CO3
    )
    before the acid hydrolysis process to produce reducing sugars using diluted sulphuric acid (H2
    SO4
    ). In this study, EFB
    fibres were irradiated at different doses, i.e. 0, 100 and 200 kGy. Meanwhile, the gamma irradiated sample were then
    subjected to Na2
    CO3 pretreatment with 0 and 5% total titratable alkali (TTA). The effect of the pretreatment using gamma
    irradiation and Na2
    CO3
    on the physical and chemical properties of the EFB fibres and the yield of the reducing sugar
    obtained from the acid hydrolysis process was investigated. The obtained results showed that the content of holocellulose
    was increased significantly with the increase of irradiation doses combined with Na2
    CO3 pretreatment, whereas lignin
    content of the EFB was decreased. The gamma irradiation and Na2
    CO3 pretreatment resulted in structure breakage
    and removal of silica of EFB fibres which can be due to the swelling of the fibres. A synergistic effect between gamma
    irradiation and Na2
    CO3 was observed, in which the yield of reducing sugars was increased by combining the gamma
    irradiation and Na2
    CO3 pretreatment.
    Matched MeSH terms: Silicon Dioxide
  16. Shear strength of cemented sand gravel and rock materials
    Zhongwei Liu, Jinsheng Jia, Wei Feng, Fengling Ma, Cuiying Zheng
    Sains Malaysiana, 2017;46:2101-2108.
    Shear strength is currently a significant parameter in the design of cemented sand gravel and rock (CSGR) dams. Shear strength tests were carried out to compare material without layers noumenon and layer condition. The experimental results showed good linearity in the curves of shear strength and pure grinding tests with correlation coefficients of nearly 97%. The friction coefficient was similar to that of C10 roller-compacted concrete (RCC), but the cohesion value was weaker than that of RCC. The shear strength of the CSGR layers decreased by 40% when retarding mixtures were not added and the layer was paved immediately after 4 h of waiting interval.
    Matched MeSH terms: Silicon Dioxide
  17. Fulltext Silicon-based induced resistance in maize against fall armyworm [Spodoptera frugiperda (Lepidoptera: Noctuidae)]
    Haq IU, Khurshid A, Inayat R, Kexin Z, Changzhong L, Ali S, et al.
    PLoS One, 2021;16(11):e0259749.
    PMID: 34752476 DOI: 10.1371/journal.pone.0259749
    The fall armyworm (Spodoptera frugiperda) is a major economic pest in the United States and has recently become a significant concern in African and Asian countries. Due to its increased resistance to current management strategies, including pesticides and transgenic corn, alternative management techniques have become more necessary. Currently, silicon (Si) is being used in many pest control systems due to its ability to increase plant resistance to biotic and abiotic factors and promote plant growth. The current experiments were carried out at the College of Plant Protection, Gansu Agricultural University, Lanzhou, China, to test the effect of Si on lifetable parameters and lipase activity of fall armyworm and vegetative and physiological parameters of maize plants. Two sources of Si (silicon dioxide: SiO2 and potassium silicate: K2SiO3) were applied on maize plants with two application methods (foliar application and soil drenching). The experiment results revealed that foliar applications of SiO2 and K2SiO3 significantly (P≤0.05) increased mortality percentage and developmental period and decreased larval and pupal biomass of fall armyworm. Similarly, both Si sources significantly (P≤0.05) reduced lipase activity of larvae, and fecundity of adults, whereas prolonged longevity of adults. Among plant parameters, a significant increase in fresh and dry weight of shoot, stem length, chlorophyll content, and antioxidant activity was observed with foliar applications of Si. Root fresh and dry weight was significantly (P ≤ 0.05) higher in plants treated with soil drenching of SiO2 and K2SiO3. Moreover, SiO2 performed better for all parameters as compared to K2SiO3 and control treatment. The study conclusively demonstrated a significant negative effect on various biological parameters of fall armyworm when plants were treated with Si, so it can be a promising strategy to control this pest.
    Matched MeSH terms: Silicon Dioxide
  18. Aluminum Microcomb Electrodes on Silicon Wafer for Detecting Val66Met Polymorphism in Brain-Derived Neurotrophic Factor
    Li Z, Cui L, Zhao H, Du J, Gopinath SCB, Lakshmipriya T, et al.
    Dev Neurosci, 2021;43(1):53-62.
    PMID: 33849012 DOI: 10.1159/000515197
    OBJECTIVE: Brain-derived neurotrophic factor (BDNF) dysregulation is widely related with various psychiatric and neurological disorders, including schizophrenia, depression, Rett syndrome, and addiction, and the available evidence suggests that BDNF is also highly correlated with Parkinson's and Alzheimer's diseases.

    METHODS: The BDNF target sequence was detected on a capture probe attached on aluminum microcomb electrodes on the silicon wafer surface. A capture-target-reporter sandwich-type assay was performed to enhance the detection of the BDNF target.

    RESULTS: The limit of detection was noticed to be 100 aM. Input of a reporter sequence at concentrations >10 aM improved the detection of the target sequence by enhancing changes in the generated currents. Control experiments with noncomplementary and single- and triple-mismatches of target and reporter sequences did not elicit changes in current levels, indicating the selective detection of the BDNF gene sequence.

    CONCLUSION: The above detection strategy will be useful for the detection and quantification of BDNF, thereby aiding in the provision of suitable treatments for BDNF-related disorders.

    Matched MeSH terms: Silicon
  19. Determination of rare earth elements concentration at different depth profile of Precambrian pegmatites using instrumental neutron activation analysis
    Sadiq Aliyu A, Musa Y, Liman MS, Abba HT, Chaanda MS, Ngene NC, et al.
    Appl Radiat Isot, 2018 Jan;131:36-40.
    PMID: 29107886 DOI: 10.1016/j.apradiso.2017.10.046
    The Keffi area hosts abundant pegmatite bodies as a result of the surrounding granitic intrusions. Keffi is part of areas that are geologically classified as North Central Basement Complex. Data on the mineralogy and mineralogical zonation of the Keffi pegmatite are scanty. Hence the need to understand the geology and mineralogical zonation of Keffi pegmatites especially at different depth profiles is relevant as a study of the elemental composition of the pegmatite is essential for the estimation of its economic viability. Here, the relative standardization method of instrumental neutron activation analysis (INAA) has been used to investigate the vertical deviations of the elemental concentrations of rare earth elements (REEs) at different depth profile of Keffi pegmatite. This study adopted the following metrics in investigating the vertical variations of REEs concentrations. Namely, the total contents of rare earth elements (∑REE); ratio of light to heavy rare earth elements (LREE/HREE), which defines the enrichment or depletion of REEs; europium anomaly (Eu/Sm); La/Lu ratio relative to chondritic meteorites. The study showed no significant variations in the total content of rare elements between the vertical depth profiles (100-250m). However, higher total concentrations of REEs (~ 92.65ppm) were recorded at the upper depth of the pegmatite and the europium anomaly was consistently negative at all the depth profiles suggesting that the Keffi pegmatite is enriched with light REEs.
    Matched MeSH terms: Silicon Dioxide
  20. Fulltext Effect of Silica Nanoparticles in Kenaf Reinforced Epoxy: Flexural and compressive properties
    Bajuri, F., Mazlan, N., Ishak, M.R.
    Pertanika Journal of Science & Technology, 2017;25(3):1029-1038.
    MyJurnal
    Kenaf natural fibre is used as a sustainable form of material to reinforce polymeric composite. However, natural fibres usually do not perform as well as synthetic fibres. Silica nanoparticle is a material with high surface area and its high interfacial interaction with the matrix results in its improvement. In this research, silica nanoparticles were introduced into epoxy resin as a filler material to improve the mechanical properties of the kenaf-reinforced epoxy. They were dispersed into the epoxy using a homogeniser at 3000 rpm for 10 minutes. The composites were fabricated by spreading the silica filled epoxy evenly onto the kenaf mat before hot pressing the resin wet kenaf mat. The results show for flexural properties, composites with higher fibre and silica volume content generally had better properties with specimen 601 (60 vol% kenaf and1 vol% silica) having the highest strength at 68.9 MPa. Compressive properties were erratic with specimen 201 (20 vol% kenaf and 1 vol% silica) having the highest strength at 53.6 MPa.
    Matched MeSH terms: Silicon Dioxide
Related Terms
Filters
Contact Us

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

External Links