UPSI Digital Repository (UDRep) : Guest Mode

Search Results

6 record(s) found

Determination of mercury(II) by single-walled carbon nanotubes paste electrode modified with zincaluminium layered double hydroxide-3(4-methoxyphenyl) propionate nanocomposite

Sharifah Norain Mohd Sharif

Abstract

This study aimed to develop a mercury(II) sensor and to identify its ability in mercury(II) determination. A mercury(II) sensor was developed by using singlewalled carbon nanotubes (SWCNTs) paste electrode modified with ZnIAl layered double hydroxide-3(4-methoxyphenyl)propionate nanocomposite (ZnIAI-LDH-MPP). Determination of optimum conditions for the detector was done by voltammetry method and subsequently confirmed by the double potential-step chronocoulometry. The results show that the optimum conditions were observed at electrode composition 2.5% (w/w) of ZnIAI-LDH-MPP/SWCNTs, OA M potassium chloride, pH 4.0, and scan rate of 100 mV S-I. The sensor exhibited wide linear range from 1.0 x l O" M to 1.0 x1O-3 M mercury(II) and 1.0 xl O" M to 1.0 xlO-7M mercury(II), with a detection limit of 1.0 xlO-lO M mercury(II). The high sensitivity of the proposed electrode towards mercury(II) was confirmed by double potential-step chronocoulometry which indicated these values; diffusion coeffic.....

Thesis Published 2015 2058 hits Available

Synthesis and characterisation of Zinc/Aluminium-Layered Double Hydroxide-L-Phenylalanate Nanocomposites using ION exchange method

Mohd Sharif Sharifah Norain, Hashim Norhayati, Md Isa Illyas, Mohd Ali Noorshida, Muhamad Damanhuri Muhd Ibrahim,

Article Published 2017 3603 hits Available

Adventure learning in basics statistics: Impact on students critical thinking

Norain Mohd Tajudin

Abstract

Malaysia Ministry of Education has put critical thinking skills elements into one of the six aspirations that pupils need to achieve. This was a turning point that teaching methods should be transformed. Therefore, innovation of teaching methods needs to be done. One of the strategies suggested is adventure-based learning (ABL). The main objective of this study is to examine the impact of ABL methods in the teaching of Basic Statistics on critical thinking skills. This study uses a quantitative approach with quasi experimental pre and post design. Only one group of students is formed. The study was based on the cluster sampling method and involving the semester two students of the Preparation Programme of Teaching Bachelor (PPTB). Instruments used are modules of adventure-based teaching methods and critical thinking skills tests. The findings of this study are to prove that this adventure-based learning can be used as an alternative method to assist the lecturers of the Teacher Educati.....

Article Published 2019 1134 hits Available

Controlled release formulation of paddy pesticides intercalated layered metal hydroxide via polysaccharide encapsulation

Sharifah Norain Mohd Sharif

Abstract

This research aimed to synthesis intercalated nanocomposites of paddy pesticides for controlled release formulation (CRF), namely zinc/aluminium–layered double hydroxide–quinclorac (Zn/Al–LDH–QC), zinc hydroxide nitrate–sodium dodecylsulphate–bispyribac (ZHN–SDS–BP) and zinc hydroxide nitrate–sodium dodecylsulphate–imidacloprid (ZHN–SDS–IC) using coprecipitation method. Surface modification of the nanocomposites, were then performed using carboxymethyl cellulose (CMC) and chitosan coatings. The physicochemical properties, CRF and kinetic behaviour were monitored using powder X–ray diffraction (PXRD), thermogravimetric analysis, Fourier transform infrared spectroscopy (FTIR), elemental analysis, field emission scanning electron microscopy (FESEM), gas sorption analysis and ultraviolet–visible spectrometer. The appearance of intercalation peaks at lower 2θ angle in the PXRD pattern, 15.8–16.7 ? (Zn/Al–LDH–QC), 28.2–28.6 ? (ZHN–SDS– BP).....

Thesis Published 2019 2364 hits Available

The effect of swellable carboxymethyl cellulose coating on the physicochemical stability and release profile of a zinc hydroxide nitrate-sodium dodecylsulphate-imidacloprid

Sharifah Norain Mohd Sharif

Abstract

The environmental pollution that results from the excessive usage of pesticides has been threatening the communities for decades. In this study, carboxymethyl cellulose (CMC) is proposed as a coating agent to encapsulate zinc hydroxide nitrate?sodium dodecylsulphate?imidacloprid (ZHN?SDS?IC) for the implementation of controlled release formulation (CRF) in pesticide. The physicochemical properties of the ZHN?SDS?IC?CMC were characterised so that their crystallinity, thermal behaviour and surface morphology could be examined. The findings from the release study revealed the potential for CMC to prolong the release of imidacloprid (IC). A strong hygroscopic and adequate swelling characteristic enabled the CMC to develop an external gel layer on the surface of the ZHN?SDS?IC?CMC that acted as an additional barrier and slowed the release of the intercalated IC. The ZHN?SDS?IC?CMC that was synthesised can contribute to overcoming the environmental issues due to excessive usage of pesticides.....

Article Published 2021 1127 hits Available

Tween–80 coating in enhancing physicochemical stability, kinetics and release mechanism of layered double hydroxide-ferulate

Sharifah Norain Mohd Sharif

Abstract

This study aims to enhance the targeted delivery of a powerful antioxidant, ferulate (FA), by developing a controlled release formulation (CRF) based on the incorporation of layered double hydroxide and Tween-80 polymeric surfactant. The layered double hydroxide-ferulate (LDH-FA) synthesized by co-precipitation method was homogenously mixed with the Tween-80 coater under continuous stirring. The successful Tween-80 coating was verified with PXRD analysis and supported by FTIR. No changes in interlayer distance between LDH-FA (at 17.4 and 8.7 A) and LDH-FA-T80 (at 17.6 and 8.6 A) were observed in the PXRD pattern. TGA/DTG analysis demonstrated good thermal stability of LDH-FA-T80, with the ability to withstand extreme temperatures up to 460 _C. The association of Tween-80 with LDH-FA progressively sustained the release time of FA in each aqueous solution, with a release time of up to 440 min. For both LDH-FA and LDH-FA-T80, the release of FA is through dissolution and anion exchange rel.....

Article Published 2024 519 hits Available

Search Results

Filter

Specific Period

Recently Accessed