In the present work, the feasibility of chitosan-graphene oxide (CS-GO) nanocomposites, namely CS-GO 1% (w/w), CS-GO 2% (w/w) and CS-GO 3% (w/w) as water-solubilising agents for rotenone pesticide was evaluated for the first time. The CS-GO nanocomposites were characterised by using FTIR, SEM, TEM and XRD analyses. The interaction of nanocomposites with rotenone was investigated through adsorption study involving several experimental parameters such as solution pH, initial concentration and contact time. Additionally, the desorption study was carried out using HCl and NaOH as desorption agents. Based on correlation coefficient (R²), the adsorption kinetic data were best described by the pseudo-first order equation while the adsorption equilibrium data were correlated well with the Langmuir isotherm model. The GO nanoparticle aggregates have a spherical shape with size ranged from 1.40 to 34.7 nm. The crystallinity of CS was increased following interaction with GO, whereby the intensit.....

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Absract Here, we have studied the behavior of ZnO based piezoelectric mechanical transducer in the presence of CO2. We have analyzed reduction-oxidation mechanism of CO2 gas on ZnO nanowire surface and studied its behavior for the enhancement piezoelectric output voltage. Rise in piezoelectric potential for various CO2 exposures time intervals from 30min to 3 h has been observed. Chemiresistive behavior of CO2 modified ZnO nanowires, is being explained by the generation of high piezoelectric voltage. ZnO nanowires based nanogenerator has been exposed to 30 min, 60 min, 90 min, 120 min and 3 h in a sealed chamber at 20 ppm, corresponding output piezoelectric voltages of 503.9 mV, 1.15 mV, 1.559 V and 1.795 V have been recorded respectively by using Picoscope 5204. It has also been observed that output voltage value has been saturated after 2 h of CO2 exposure. ZnO nanowire based VING (vertically integrated nanowire generator) structure is being used for the study under minute external f.....

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As part of our continuing search to explore novel natural compounds from Beilschmiedia species, we have carried out a phytochemical study of the leaves and stem bark extracts of B. penangiana. As a result, four alkaloids, (+)-reticuline (1) [8], (+)-boldine (2) [9], (+)-norboldine (3) [10], and lindcarpine (4) [10] together with five other compounds, β-sitosterol (5) [7], β-sitostenone (6) [7], lupeol (7) [6], lupenone (8) [6], and taraxerol (9) [7], were successfully isolated  ..

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This study aims to assess the chemical compositions of the essential oils from three Horsfieldia species namely H. fulva Warb., H. sucosa Warb. and H. superba Warb., which are found in Malaysia. The essential oils were derived from the samples through hydro-distillation which were then characterised by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Based on the findings, the H. fulva, H. sucosa and H. superba essential oils represented 98.2%, 98.7% and 98.5% of the total oils, respectively. The major component of H. fulva oil was identified to be germacrene D (20.8%), H. sucosa oil mainly contained a-cadinol (17.5%), whereas H. superba oil was rich in d-cadinene (18.2%). To the best of our knowledge, this is the first study of the composition of the essential oils from these selected Horsfieldia species. ARTICLE HISTORY  ..

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Polyalthia is one of the largest genera in the Annonaceae family, and has been widely used in folk medicine for the treatment of rheumatic fever, gastrointestinal ulcer, and generalized body pain. The present investigation reports on the extraction by hydrodistillation and the composition of the essential oils of four Polyalthia species (P. sumatrana, P. stenopetalla, P. cauliflora, and P. rumphii) growing in Malaysia. The chemical composition of these essential oils was determined by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The multivariate analysis was determined using principal component analysis (PCA) and hierarchical clustering analysis (HCA) methods. The results revealed that the studied essential oils are made up principally of bicyclogermacrene (18.8%), cis-calamenene (14.6%) and β-elemene (11.9%) for P. sumatrana; α-cadinol (13.0%) and δ-cadinene (10.2%) for P. stenopetalla; δ-elemene (38.1%) and β-cubebene (33.1%) for P. cauliflora; a.....

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The chemical composition of the essential oil from the leaves of Diospyros wallichii (Ebenaceae) growing in Malaysia was investigated for the first time. The essential oil was obtained by hydrodistillation and fully characterized by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). A total of 34 components (95.8%) were successfully identified in the essential oil which were characterized by high proportions of β-eudesmol (28.5%), caryophyllene oxide (9.5%), β-caryophyllene (7.2%), α-eudesmol (6.5%) and germacrene D (6.2%).   ..

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Pegangan hidup berbudaya telah menyebabkan manusia mempercayai akan wujudnya alam lain selepas kehidupan. Bagi masyarakat Iban di Sarawak mereka percaya akan alam kematian selepas kehidupan yang disebut sebagai alam Sebayan. Alam Sebayan diceritakan secara turun temurun oleh generasi Iban secara lisan dan banyak mempengaruhi dalam cerita dongeng Iban dan budaya ketara dan tidak ketara masyarakat Iban. Dalam budaya Iban terdapat pelbagai adat dan pantang larang yang telah ditetapkan oleh pencipta yang dipanggil sebagai Petara dalam menjaga keseimbangan hubungan dunia kosmologi Iban. Dalam adat kematian Iban, satu upacara khas iaitu upacara Nyabak harus dilakukan dengan mengupah khidmat Tukang Sabak. Tukang Sabak memainkan peranan penting bagi menghantar roh si mati ke tempat yang sepatutnya dengan lancar. Penyelidikan ini membincangkan terhadap budaya Nyabak dan peranan Tukang Sabak dalam adat kematian masyarakat Iban di Sarawak...

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Kajian ini dibuat sempena pameran Negaraku 2017 di Balai Seni Visual Negara, Kuala Lumpur. Karya yang dipilih dalam pameran ini berbentuk nasionalisme mengupas tentang apreasasi karya berbentuk nasionalisme dalam pameran Negaraku 2017 memfokuskan kedua menyatakan ciri-ciri subjek nasionalisme yang terkandung dalam karya dan fokus seterusnya menginterpretasi makna karya nasionalisme dalam konteks seni moden Malaysia. Karya untuk pameran “Negaraku” bertujuan untuk mengenalpasti bentuk karya-karya nasionalisme dalam pameran seni Negaraku manakala ia menyatakan ciri-ciri subjek nasionalisme yang terkandung dalam karya-karya seni rupa di dalam pameran seni “Negaraku” dan ingin menginterpretasi makna karya nasionalisme dalam konteks seni moden Malaysia. Penyelidik menggunakan pendekatan kualitatif kajian kes. Kaedah pengumpulan data melalui penelitian (observasi), temubual, rakaman visual dan dokumentasi. Seterusnya data ini di analisis menggunakan model kajian Edmund Burke Feldmen (.....

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Kajian rintis yang dilaksanakan ini merupakan program seni sebagai terapi melalui program seni kreatif di penjara Kajang Malaysia. Ia terdiri daripada aktiviti melukis menggunakan pelbagai medium seni yang melibatkan 20 orang banduan lelaki dan 20 orang banduan wanita berumur antara 21 hingga 63 tahun. Tempoh program ini adalah selama 12 minggu dan 3 jam bagi setiap sesi. Rangka kerja untuk program ini disediakan hasil dari tinjauan literatur dan input dari sesi temubual berstruktur yang dijalankan dengan pakar psikologi dari Universiti Utara Malaysia (UUM) serta pegawai psikologi penjara dari Pusat Koreksional Perlis. Program akan dijalankan di bengkel vokasional penjara berdasarkan tema spesifik menggunakan medium seni seperti kertas lukisan, pen dakwat dan cat air. Kajian ini juga membincangkan tentang kaedah untuk memperkenalkan rangka program yang dicadangkan di penjara Malaysia. Aktiviti seni sebagai terapi dalam program ini bermula dengan sesi pengenalan dan beberapa latihan unt.....

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Makalah ini adalah satu semakan terhadap program CuratorsLAB yang pernah dijalankan pada 2015 sehingga 2017. Ianya dianjurkan oleh Goethe Institut Indonesia, Institut Teknologi Bandung dan Portikus Am Main, Frankfurt, Jerman yang menemukan kurator-kurator muda dari Asia Tenggara. Tujuannya adalah untuk mencari kesefahaman dan melihat permasalahan yang terdapat di Asia Tenggara. Kaedah pengumpulan data termasuk temuduga, pemerhatian dan penglibatan secara langsung selama dua tahun mengikut fasa-fasa tertentu bermula dari Fasa 1: Bandung, Fasa 2: Lawatan ke galeri-galeri di Jerman, Fasa 3: Ribut Akal di Bangkok, Thailand dan Fasa 4: Mutual Unknown- pameran kontemporari Asia Tenggara di Jakarta, Indonesia. Kepentingan program ini adalah ianya mendedahkan para kurator muda di Asia Tenggara tentang ilmu kuratorial, memahami budaya di setiap negara-negara yang mengambil bahagian dan akhirnya mengetahui apa permasalahan sebenar yang terdapat di Asia Tenggara. Persoalan yang terdapat pada Asia.....

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