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"Kebutuhan manusia akan minyak bumi sebagai sumber bahan baku industri petrokimia semakin besar. Sehingga, diperlukan sumber bahan baku alternatif sebagai pengganti minyak bumi, salah satunya adalah gliserol yang keberadaannya sangat melimpah di alam sehingga perlu dimanfaatkan. Gliserol merupakan produk hasil samping pembuatan biodiesel yang terbentuk dari trigliserida melalui proses transesterifikasi. Tujuan penelitian ini adalah untuk mempelajari proses konversi gliserol menjadi hidrokarbon aromatik dengan katalis Al2O3 dan HZSM-5 serta mengusahakan agar yield mencapai nilai setinggi-tingginya. Konversi gliserol dilakukan pada reaktor semi-batch dengan memvariasi suhu reaktor dan rasio massa umpan terhadap katalis. Produk yang dihasilkan dianalisis menggunakan instrument GC-FID.

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Humans need of petroleum as feedstock source in petrochemical industry is getting bigger from year to year. Therefore, we need alternative feedstock source replacing the petroleum, such as glycerol of which there are plenty in nature so that it needs to be used. Glycerol is a byproduct of biodiesel production which is formed from triglycerides through transesterification process. The purpose of this research is to study about conversion process from glycerol to aromatic hydrocarbons using catalyst of Al2O3 and HZSM-5 alloys and also to achieve high aromatic yield. Glycerol conversion was done in a half-batch reactor with varying the reactor temperature and feed-to-catalyst mass ratio. The final products were analyzed using GC-FID instrument."

"Polisiklik Aromatik Hidrokarbon (PAH) merupakan salah satu jenis bahan pencemar organik yang dapat dihasilkan dari pembakaran yang tak sempurna (pirogenik) ataupun dari kegiatan perminyakan (petrogenik). Pertambakan adalah salah satu kawasan yang rentan akan bahan pencemar organik. Pada penelitian ini dilakukan analisis terhadap sedimen dan Udang Windu (Penaeus monodon) di pertambakan untuk mengetahui kadar senyawa PAH yang dipengaruhi oleh tataguna lahan dan vegetasi mangrove. Sampel yang sudah kering kemudian diekstraksi dengan soxhlet selama ± 18 jam dengan 250 mL pelarut campuran (1:1) n-heksan : diklorometan (DCM) lalu di fraksinasi menggunakan kolom berisi silika gel, alumina dan natrium sulfat dengan 40 mL pelarut campuran (1:1) n-heksan : diklorometan (DCM) untuk mendapatkan fraksi aromatik. Hasil fraksinasi kemudian dievaporasi dan diblow up dengan gas helium hingga tepat 1 mL, lalu diambil 2 μL untuk analisa dengan GC-MS (Gas Chromatography-Mass Spectrometry). Hasil analisa menunjukkan bahwa konsentrasi Naphthalene di sedimen Blanakan dan Marunda berkisar antara 0.0944 ng.g-1 - 9.9069 ng.g-1 dan 0.1691 ng.g-1 - 8.3503 ng.g-1. Sedangkan untuk konsentrasi benzo(a)pyrene di sedimen blanakan dan Marunda berkisar antara 2.6294 ng.g-1 - 5.2302 ng.g-1 dan 4.0760 ng.g-1 - 6.3368 ng.g-1. Konsentrasi senyawa naphthalene pada tubuh udang windu di kawasan Marunda dan Blanakan sebesar 4.7080 ng.g-1 dan 1.6322 ng.g-1 serta untuk senyawa benzo(a)pyrene di kawasan Marunda dan Blanakan sebesar 1.5367 ng.g-1 dan 1.2910 ng.g-1.

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Polycyclic Aromatic Hydrocarbons (PAH) is one type of organic pollutants can be produced from incomplete combustion (pyrogenic) or from petroleum activities (petrogenik). Aquaculture is one of the areas that are vulnerable to organic pollutants. In this research, analysis of sediment and tiger prawn (Penaeus monodon) in aquaculture to determine levels of PAH compounds that are affected by land use and mangrove vegetation. The dried samples were then extracted by Soxhlet for ± 18 hours with 250 mL solvent mixture (1:1) n-hexane: dichloromethane (DCM) and fractionated using a column containing silica gel, alumina and sodium sulfate with 40 mL of solvent mixture (1 : 1) n-hexane: dichloromethane (DCM) to obtain the aromatic fraction. Results of fractionation then evaporated and blow up with helium gas to exactly 1 mL, 2 μL of result then taken for analysis by GC-MS (Gas Chromatography-Mass Spectrometry). The analysis shows that the concentration of Naphthalene in sediments Blanakan and Marunda ranged between 0.0944 ng.g-1 - 9.9069 ng.g-1 and 0.1691 ng.g-1 - 8.3503 ng.g-1. As for the concentration of benzo(a)pyrene in sediment Blanakan and Marunda range between 2.6294 ng.g-1 - 5.2302 ng.g-1 and 4.0760 ng.g-1 - 6.3368 ng.g-1. The concentration of naphthalene compound in prawn's body in the Marunda and Blanakan ranged from 4.7080 ng.g-1 to 1.6322 ng.g-1 and for benzo(a)pyrene compound in the Marunda and Blanakan from 1.5367 ng.g-1 to 1.2910 ng.g-1."

"Kebakaran hutan dan lahan menghasilkan asap yang diketahui mengandung Polycyclic Aromatic Hydrocarbon (PAH). Efek adanya kerusakan oksidatif pada DNA akibat paparan asap kebakaran hutan dan lahan terhadap risiko kanker diselidiki melalui deteksi biomarker 8-Hidroksi-2’-Deoksiguanosin (8-OHdG) dan 1-Hidroksipiren (1- OHP), metabolit utama piren, sebagai indikator paparan PAH dalam urin. Analisis biomarker paparan PAH dalam urin 24 jam dilakukan secara acak dalam suatu populasi di Kota Dumai, Provinsi Riau. Kandungan 8-OHdG dalam sampel urin dianalisis menggunakan HPLC detektor UV dengan fasa gerak buffer natrium fosfat 0,1 M pH 6,7 dan metanol (85:15, v/v). Sementara, kandungan 1-OHP dalam urin dideteksi menggunakan HPLC detektor flourosens dengan eluen metanol dan air (60:40, v/v). Analisis kedua senyawa tersebut dilakukan dengan kromatografi fasa terbalik mode isokratik. Hasil pengujian menunjukan bahwa 8-OHdG terdeteksi pada seluruh sampel dalam rentang konsentrasi 25,29 g/L hingga 2,16 mg/L urin (n = 11), lebih tinggi dibandingkan dengan konsentrasi 8-OHdG dalam urin individu sehat (1,42 μg/L – 4,25 μg/L). 1-OHP dalam urin juga terdeteksi dalam empat dari lima sampel yang diuji, menandakan bahwa terdapat potensi besar kerusakan oksidatif DNA akibat paparan PAH

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orest fires generate woodsmoke that contain Polycyclic Aromatic Hydrocarbon (PAH). The effect of DNA oxidative damage due to woodsmoke exposure on cancer risk can be investigated through the detection of urinary 8-Hydroxy-2’-Deoxyguanosin (8-OHdG) and 1-Hydroxypyrene, main metabolite of pyrene, as indicators of PAH exposure. Analysis biomarkers of PAH exposure in 24 hours urine was performed within a population randomized in Dumai City, Riau Province. The 8-OHdG levels in urine samples were analyzed by using HPLC with UV detector using sodium phosphate buffer 0.1 M pH 6.7 and methanol (85:15, v/v) as mobile phase. Meanwhile, 1-OHP levels in urine was detected by using a HPLC with fluorosens detector using methanol and water (60:40, v/v) eluent. Analysis of both compounds was performed by reverse phase chromatography with isoratic mode. The results showed that 8-OHdG was detected in all samples with concentration range of 25.29 μg/L to 2.16 mg/L urine (n = 11), higher than urinary 8-OHdG of health person (1,42 μg/L – 4,25 μg/L). Urinary 1- OHP was also detected in four of five samples. It indicates that there was a high potential of DNA damage caused by PAH exposure"

"Written by an award-winning naval architecture author and former vice-president of the Royal Institution of Naval Architects (RINA), the fifth edition of Introduction to naval architecture has been fully updated to take in advances in the field and is ideal both for those approaching the subject for the first time and those looking to update or refresh their knowledge on areas outside of their direct expertise.This book provides a broad appreciation of the science and art of naval architecture, explaining the subject in physical rather than in mathematical terms. While covering basic principles, such as hull geometry, propulsion, and stability, the book also addresses contemporary topics, such as computer aided design and computer aided manufacture (CAD/CAM). The new edition reflects the continuing developments in technology, changes in international regulations and recent research."

"Senyawa turunan tiohidantoin memiliki aktivitas biologis yang beragam seperti antioksidan, antikonvulsan, dan antimikroba. Pada penelitian ini telah dilakukan sintesis turunan 2-tiohidantoin melalui intermediet tiosemikarbazon menggunakan aldehida aromatik (vanilin, benzaldehida, 4-hidroksibenzaldehida, dan sinamaldehida) sebagai prekursor dan tiosemikarbazida dengan adanya katalis nanopartikel ZnO. Nanopartikel ZnO yang digunakan disintesis melalui metode green synthesis dari ekstrak daun teh (Camellia sinensis) dan dikarakterisasi menggunakan FTIR, XRD, SEM, dan BET. Dari spekrum XRD dikonfirmasi bahwa ZnO yang disintesis memiliki fase heksagonal wurtzite dengan ukuran kristal sebesar ~36,54 nm yang dihitung melalui persamaan Debye-Scherer. Kondisi optimum untuk reaksi sintesis turunan tiosemikarbazon adalah dengan menggunakan katalis ZnO sebesar 5 mol%. Senyawa turunan tiosemikarbazon yang diperoleh merupakan intermediet dari reaksi sintesis senyawa turunan 2-tiohidantoin. Pada penelitian ini diperoleh senyawa sinamaldehida tiohidantoin dengan yield sebesar 82,42%, vanilin tiohidantoin 78,44%, benzaldehida tiohidantoin 78,26%, dan 4-hidroksibenzaldehida tiohidantoin 76,58%. Senyawa turunan 2-tiohidantoin memiliki aktivitas antioksidan yang berbeda-beda ketika dilakukan variasi menggunakan senyawa aldehida aromatik. Aktivitas antioksidan dari senyawa turunan 2-tiohidantoin ditentukan dari nilai IC50 dimana vanilin tiohidantoin memiliki nilai IC50 sebesar 153,07 ppm, kemudian senyawa 4-hidroksibenzaldehida tiohidantoin sebesar 296 ppm, sinamaldehida tiohidantoin sebesar 377,31 ppm, dan benzaldehida tiohidantoin 475,47 ppm.

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Thiohydantoin derivarive compounds are known to have biological activities, such as antioxidants, anticonvulsants, and antimicrobials. In this study, the synthesis of 2-thiohydantoin derivatives via thiosemicarbazone intermediates was carried out using aromatic aldehydes (vanillin, benzaldehyde, 4-hydroxybenzaldehyde, and cinnamaldehyde) as precursors and thiosemicarbazide in the presence of ZnO nanoparticles as a catalyst. The ZnO nanoparticles were synthesized through the green synthesis method from tea leaf extract (Camellia sinensis) and were characterized using FTIR, XRD, SEM, and BET. The hexagonal phase with wurtzite structure was confirmed by X-ray diffraction study. The size of the ZnO NPs were calculated using the Debye-Scherer equation and it was found to be ∼36,54 nm. The optimum conditions for the synthesis reaction of thiosemicarbazone derivatives is to use 5 mol% of ZnO NPs. The thiosemicarbazone derivatives are intermediates from the synthesis reaction of 2-thiohydantoin derivatives. In this study, cinnamaldehyde thiohidantoin was obtained with a yield of 82,34%, vanillin thiohydantoin 78,25%, benzaldehyde thiohidantoin 78,26%, 4-hydroxybenzaldehyde thiohidantoin 76.51%. The antioxidant ability of the 2-thiohydantoin derivatives was assessed from the IC50 value where the vanillin thiohydantoin compound was 153,07 ppm, 4-hydroxybenzaldehyde thiohydantoin compound was 296 ppm, cinnamaldehyde thiohydantoin was 377,31 ppm, and benzaldehyde thiohydantoin was 475,47 ppm."