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"Reaksi katalisis heterogen telah banyak diaplikasikan untuk menggantikan reaksi katalisis homogen dimana katalis yang digunakan umumnya sulit dipisahkan dengan produk hasil reaksi. Terlebih lagi pada beberapa katalis homogen bersifat tidak ramah lingkungan seperti reaksi nitrasi yang menggunakan katalis homogen asam sulfat pekat. Pada penelitian ini dilakukan modifikasi struktur eugenol hasil isolasi dari minyak cengkeh melalui reaksi nitrasi pada aromatik eugenol. Reaksi nitrasi dilakukan melalui katalisis homogen asam sulfat pekat dan katalisis heterogen dengan SiO2 - H2SO4 sintesis sebagai katalis heterogen. Hasil produk nitro-eugenol tersebut dikarakterisasi menggunakan TLC-Scanner, LC-MS, dan GC. Hasil TLC mengindikasikan hasil reaksi selama 5 jam dengan katalis asam SiO2 - H2SO4 terdapat eugenol yang belum terkonversi sehingga dilakukan variasi waktu reaksi: 6, 12, dan 18 jam reaksi. Hasil analisis MS pada katalisis heterogen 18 jam reaksi menunjukan terdapat dua gugus nitro yang tersubstitusi pada aromatik eugenol sedangkan pada katalisis homogen tersubstitusi tiga gugus nitro. Berdasarkan analisis GC didapatkan %konversi nitro-eugenol hampir mencapai 100% pada 6, 12, dan 18 jam reaksi, dan %yield sebesar 78,394%; 87,371% dan 99,960% secara berurutan.

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Heterogeneous catalysis reactions have been applied to replace homogeneous catalysis reactions in which the catalyst are generally difficult to separate from the reaction products. Moreover some of homogeneous catalysis reaction are environmentally unfriendly such as nitration reactions using concentrated sulfuric acid. In this study, the structure of isolated eugenol from clove oil was modified through the aromatic nitration reaction. The nitration reaction were performed over homogeneous catalysis and heterogeneous catalysis reaction using SiO2 - H2SO4 as the heterogenous catalyst.

The reaction products nitro-eugenol were characterized using TLC-Scanner, LC-MS, and GC. The identifications by TLC indicated that the heterogenous nitration reactions of eugenol had not succeded converted most of the eugenol in 5h reaction time, so that the reaction times were varied from 6h to 18h. The MS analysis showed that two nitro groups were bound to the aromatic ring of eugenol over heterogenous catalysis, whereas over the homogenous catalysis three nitro groups were bound to the aromatic ring of eugenol. Based on GC analysis, the %conversion of eugenol were almost 100% for 6h, 12h, and 18h of reaction times and the %products distribution were 78.39%, 87.37% and 99.96% successively."

"Analisa pelumas adalah bagian dari kegiatan pemeliharaan prediktif yang dilakukan secara rutin pada banyak industry karena lebih efektif dan efisien untuk mencegah kemungkinan kerusakan lebih dini dan pemborosan dalam biaya pemeliharaan. Sehingga pada Penelitian ini dikembangkan prototype sensor berbasis near infra red untuk menganalisa sisa umur pelumas. Sensor mendeteksi gugus N-H pada bilangan gelombang 9000-10000 cm-1 yang merupakan hasil dari proses degradasi pelumas.Hasil penelitian menunjukkan sensor near infra read dapat mendeteksi perubahan sisa umur pelumas dan menunjukkan kecenderungan yang sama dengan p.

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Lubricant analysis is part of routine predictive maintenance in many industry because more effective and efficient to avoid possible engine failure and unnecessary cost. So in this research was developed a prototype near infra red sensor to analysis remaining useful lubricant life. This sensor detected N-H spectrum at 9000-10000 cm-1 where is lubricant degraded.The result was shown near infra red detected the change of remaining useful lubricant life and shown similar trend with the change of lubricant viscosity, lubricant acidity (Total Acid Number), and FTIR spectrum."

"Isatin atau 1H-indol-2,3-dion, merupakan senyawa bahan alam yang dapat ditemukan dalam tanaman dari genus Isatis. Studi terhadap bioaktivitas isatin menunjukkan potensi sebagai antivirus, anti-HIV, antimikroba, antitumor, antiinflamasi, antikejang, antibakteri, dan antijamur. Pada penelitian ini, sintesis senyawa turunan oxindol dilakukan melalui dua tahap. Pertama, prekursor isatin direaksikan dengan TCCA untuk memperoleh intermediet 1, 5-kloroisatin, dan juga dengan NaNO3 untuk memperoleh intermediet 2, 5-nitroisatin. Diperoleh yield intermediet 1 sebesar 45% dan intermediet 2 sebesar 58,2%. Kemudian, senyawa prekursor, intermediet 1, dan intermediet 2 direaksikan dengan malononitril melalui reaksi Kondensasi Knoevenagel terkatalisis I2 untuk memperoleh senyawa turunan oxindol. Reaksi dioptimasi dan diperoleh kondisi optimum untuk memperoleh senyawa turunan oxindol yaitu pada 10% mol katalis, suhu reaksi 75oC, dan dalam pelarut protik, etanol. Keberhasilan sintesis senyawa intermediet dan senyawa turunan oxindol dianalisa menggunakan kromatografi lapis tipis (KLT), UV-Vis, FTIR, GC-MS, LC-MS, dan Melting Point-Apparatus. Diperoleh yield senyawa turunan oxindol 1 dengan prekursor isatin sebesar 71,13%, senyawa turunan 2 dengan prekursor 5-kloroisatin 61,39%, dan senyawa turunan 3 dengan prekursor 5-nitroisatin sebesar 67,39%. Hasil uji aktivitas antimikroba pada senyawa turunan oxindol 1, 2, dan 3 menunjukkan aktivitas yang lemah terhadap bakteri uji S. aureus dan E. coli. Uji aktivitas antioksidan dengan DPPH memberikan nilai IC50 masing-masing 266,47 ppm, 220,43 ppm, dan 654,85 ppm untuk senyawa turunan oxindol 1, 2, dan 3.

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Isatin or 1H-indole-2,3-dione, is a natural compound that can be found in plants of the genus Isatis. Studies on the bioactivity of isatin show potential as antiviral, anti-HIV, antimicrobial, antitumor, anti-inflammatory, anticonvulsant, antibacterial, and antifungal properties. In this study, the synthesis of oxindol derivatives was carried out in two stages. First, isatin was reacted with TCCA to obtain intermediate 1, 5-chloroisatin, and also with NaNO3 to obtain intermediate 2, 5-nitroisatin. The yield obtained of intermediate 1 is 45% and intermediate 2 is 58.2%. Then, the precursor compounds, intermediate 1, and intermediate 2 were reacted with malononitrile through the I2-catalyzed Knoevenagel condensation reaction to obtain oxindole derivatives. The reaction was optimized and optimum conditions were obtained to obtain oxindole derivatives, namely at 10% mole of catalyst, reaction temperature of 75oC, and in protic solvent, ethanol. The success of the synthesis of intermediates and oxindol derivatives was analyzed using thin layer chromatography (TLC), UV-Vis, FTIR, GC-MS, LC-MS, and Melting Point-Apparatus. The yield of oxindol derivative compound 1 with isatin as the precursor was 71.13%, derivative compound 2 with 5-chloroisatin as the precursor was 61.39%, and derivative compound 3 with 5-nitroisatin as the precursor was 67.39%. The results of the antimicrobial activity test on oxindol derivatives 1, 2, and 3 showed weak activity against both test bacteria, S. aureus and E. coli. The antioxidant activity test with DPPH gave IC50 values of 266.47 ppm, 220.43 ppm, and 654.85 ppm for oxindol derivatives 1, 2, and 3, respectively. "