The study on thiourea derivatives and its coordination complexes have been well documented with majority of the synthesized compounds have high potential to be used as antibacterial agents. In line with this interest, two thiourea ligands derived from amino acids, namely 2-(3-dodecanoyl-thioureido)-3-methylbutyric acid (L1) and 2-(3- dodecanoylthioureido)-3-phenylpropionic acid (L2) have been reacted with ZnCl2 and CuCl2, to produce three new complexes with general formula of [Zn(L1)Cl2] (1), [Zn(L2)Cl2] (2) and [Cu(L2)Cl2] (3) as suggested by elemental analysis. The complexes were characterized by spectroscopic techniques such as Fourier Transform Infrared (FTIR) and Ultraviolet-Visible (UV-Vis). The antibacterial activities of the complexes were evaluated against three common Gram-positive strains (S. aureus, S. epidermidis and B. subtilis) and two Gram-negative strains (E. coli and S. typhimurium). This study revealed that complex 3 had a good antibacterial activity towards Gram-pos.....

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An extremely easy method is presented for producing TiO2 nanoparticles (NPs) films as photoanode in dye-sensitized solar cell applications. This paper presents the study on the effect of Polyethylene glycol 20000 (PEG 20000) on the properties of TiO2 NPs films. The amount of PEG 20000 were varied between 0.1 and 0.5 g. Sonication and stirring of commercial TiO2 NPs Degussa P25 and PEG 20000 in ethanol results in highly homogeneous dispersions which are used to prepare TiO2 films. The use of optimum amount of PEG 20000 will increase the light absorption due to the increment of the surface area within the film. The films were characterised using ultraviolet-visible-near infrared spectrometer, field emission scanning electron microscopy and current-voltage measurement...

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Snail allergy is rare, but it can lead to severe allergic reactions. Life-threatening reactions including anaphylactic shock have been often reported after snail consumption. Cerithidea obtusa is a commonly consumed sea snail in Malaysia and other Asian countries. The purpose of this study was to determine the frequency of immediate hypersensitivity reactions to this species of snail by skin prick test (SPT). Snail proteins were extracted from the snail flesh. A total of 131 patients with atopic diseases were skin prick tested with the snail extract. Out of 131 subjects, 10 (8%) were sensitized to C. obtusa extract. Most of these subjects are allergic rhinitis (70%), allergic conjunctivitis (60%), asthma (20%) and food allergic (20%) patients. As a conclusion, this study showed that the immediate hypersensitivity to marine snail, C. obtusa exists among local atopic patients at a low frequency of 8%. It seems like a patient with C. obtusa sensitization is also probably to be sensitized .....

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The aim of this study is to determine the effectiveness of multi-frames video recorded experiments (MFVREs) on pre-university students’ achievement for capacitor topic. This study was carried out among 60 Diploma Science students of Universiti Pendidikan Sultan Idris, Malaysia. Students’ pre-test and post-test scores were analyzed using independent sample t-test. The effectiveness of MFVREs on students’ achievement were analyzed for four subtopics of capacitor: basic concept of capacitor (S1), series connection of capacitors (S2), parallel connection of capacitors (S3) and combination of series and parallel connection of capacitors (S4). Findings revealed that MFVREs give significant effects on students’ achievement for S2, S3 and S4 subtopics but no significant effect to students’ achievement for S1 subtopic compared to PowerPoint slides. Thus, MFVREs approach can be used either as a teaching aid in normal classroom or a student-centered learning video in order to improve th.....

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The increasingly widespread of using computers in daily life has brought the piranti as assistant for human. One of the application computer in the field of security has increased it is role is in terms of facial recognition. Face recognition is the process of human identification with the face image. With the increasingly widespread use of computers, is expected to face recognition capabilities can be adapted on the smart device. The adaption process became possible with the discovery of variety of facial recognition methods, one of which is the Principal Component Analysis (PCA). Research began by designing a computer program using the programming language Matlab. The program is used to test the results of PCA with several facial image. At the end it can be concluded that PCA is quite worthy of a face recognition method. The research data shows recognition results were pretty good with quite small error rate...

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Thiourea is known to be a unique class of organic compounds especially acylthiourea since they consist excellent Hbonds donor and acceptor where it has strong ability to form metal complexation with various metal salts. Therefore, six members of acylthiourea derivatives (TH1-TH6) have been successfully synthesized and characterised using selected spectroscopic and analytical methods namely Fourier-Transform Infrared (FT-IR) spectroscopy, UV-visible (UV-vis) spectrophotometer, and CHNS elemental analysis. In turn, all the synthesised TH1-TH6 were used to investigate the anti-bacterial activity towards selected bacteria of both Gram-negative and positive namely Salmonella typhi and Bacillus cereus respectively. TH1-TH6 revealed to have good activity towards S. typhi and B. cereus with specific and broad-range spectrum activity...

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In this study, new members of alkyl substituted thiourea derivatives of (RC(O)NHC(S)NHCH2CH(CH3)NHC(S)NHC(O)-R) in which R represents alkyl group namely isobutyryl and pivaloyl were successfully synthesized for their antibacterial activities. The compounds were spectroscopically and analytically characterized via infrared (IR) spectroscopy, ultraviolet–visible (UV– vis) spectroscopy, CHNS elemental analysis as well melting point analysis. In turn, they were screened for antibacterial activity using selected bacteria namely, Micrococcus sp., Salmonella typhi, Aeromonas sp., Klebsiella pneumoniae, Bacillus cereus and also Escherichia coli. From the antibacterial test, all synthesized compounds were found to exhibit great potential results as antibacterial agents, except for 1 which did not show inhibition activity towards Klebsiella pneumoniae. Thus, these proposed molecular structures have given ideal indication to act as antibacterial agents which have utmost potential in pharmaceu.....

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Synthesis of graphene with the high surface area has been very attractive for various energy storage applications. In this work, we describe a scalable method for producing edge scrolled reduced graphene oxide (r-GO) with the high surface area by modified Hummer’s method. Strong acid treated graphite flakes were used to synthesis reduced graphene oxide. Few layered, edge scrolled reduced graphene oxide was obtained by low temperature (200℃) thermal treatment in a hydrogen atmosphere. The formation of few layered graphitic structure of reduced graphene oxide was confirmed by TEM analysis. The specific surface area of the reduced graphene oxide was measured by nitrogen adsorption technique. The reduced graphene oxide derived from acid treated graphite flakes exhibits high surface area (~ 500 m2/g) than non acid treated graphite flakes (214.4 m2/g)...

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Recently, porous silicon (PS) gains a lot of research interest with its potential applications in optoelectronics, flat panel displays technology, and chemical sensor. In this work, PS was chemically etched on p-type silicon (Si) wafer by hydrofluoric acid (HF) with 40% nitric acid (HNO3) concentration at different etching time. The PS has porosity dependent on etching time in the range (38-60) % that gives orange-red photoluminescence (PL) between 657 nm to 661 nm. The PL intensity increases and the peak wavelength shows slight blue shift as etching time increases. The energy gap obtained are higher than pure Si (1.11eV). Meanwhile, the conductivity of the PS decreases as the porosity and energy gap increase...

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Synthesis of carbon nanotubes with different concentrations of ferrocene (C10H10Fe) as catalyst (5.33, 10.66, 13.99- 19.99 wt%) from waste engine oil precursor has been done to study its effects on the growth of carbon nanotubes. Thermal chemical vapor deposition method was used in this study. The synthesis process lasted for 30 minutes under argon gas ambient in constant precursor vaporization and synthesis temperature of 450°C and 750°C respectively. The characterization of prepared samples were done using field emission scanning electron microscopy, micro-Raman spectroscopy and thermogravimetric analysis. High density carbon nanotubes was produced at 17.99 wt% catalyst concentration with purity of 72%. The results show that the structure, diameter size and quality of carbon nanotubes are highly affected by the catalyst concentrations...

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