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"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."

"Provides a thorough overview of the role of fluorine in pharmaceutical science and development Includes chapters on fluorinated analogues of natural products, fluorinated amino acids and peptides, and derivatives of sugars classifies marketed and in-development fluorinated pharmaceuticals according to their therapeutic classes."

"Heterocycles have played a crucial role in the biological and industrial development of society, becoming one of the most researched areas within organic chemistry.The first chapter, is based on microwave theory, the latest developments in instrumentation technology, and the various microwave technologies used for synthesis. The remainder of the chapters are divided into two sections. Section A deals with the five-membered heterocycles (pyrazoles, isoxazoles, triazoles, oxadiazoles, thiazoles, imidazoles, oxazoles, oxazolines etc.) and in Section B, various six-membered heterocycles (triazines, benzoxazoles, benzimidazoles, benzothiazoles) are presented. Both sections contain a detailed, recent literature review of microwave assisted synthesis and its applicability to various aromatic heterocyclics."

"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."

"Senyawa turunan tiosemikarbazon merupakan senyawa yang mempunyai aktivitas biologis yang baik, yaitu sebagai antioksidan, antitumor, dan antimikroba. Pada penelitian kali ini, telah dilakukan sintesis senyawa turunan tiosemikarbazon dengan menggunakan limonen dan empat senyawa aldehid aromatik yang berbeda yaitu benzaldehid, 4-hidroksibenzaldehid, sinamaldehid, dan vanilin. Produk akhir senyawa turunan tiosemikarbazon yang terbentuk diidentifikasi menggunakan KLT serta dikarakterisasi menggunakan Fourier Transform Infrared spectroscopy (FTIR), Spektrofotometri UV-Vis, dan Gas Chromatography Mass Spectrometry (GC-MS). Produk akhir senyawa turunan tiosemikarbazon diuji aktivitas antioksidannya dengan menggunakan metode 1,1-Difenil-2-pikril-hidrazil (DPPH). Pada penelitian ini diperoleh produk benzaldehid limonen tiosemikarbazon dengan persen rendemen sebesar 58,18%, 4-hidroksibenzaldehid limonen tiosemikarbazon dengan persen rendemen sebesar 49,47%, vanilin limonen tiosemikarbazon dengan persen rendemen sebesar 43,91%, dan sinamaldehid limonen tiosemikarbazon dengan persen rendemen sebesar 73,01%. Kemampuan antioksidan tertinggi diperoleh oleh senyawa vanilin limonen tiosemikarbazon dengan nilai IC50 sebesar 108,8 ppm dan kemampuan antioksidan terendah diperoleh oleh senyawa benzaldehid limonen tiosemikarbazon dengan nilai IC50 sebesar 177,2 ppm.

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Thiosemicarbazone derivatives are compounds that have good biological activity, such as antioxidant, antitumor, and antimicrobial. In this study, thiosemicarbazones derivative compounds were synthesized using limonene and four different aromatic aldehydes, such as benzaldehyde, 4-hydroxybenzaldehyde, cinnamaldehyde, and vanillin. The final product of the thiosemicarbazone derivatives were identified using TLC and characterized using Fourier Transform Infrared spectroscopy (FTIR), UV-Vis Spectrophotometry, and Gas Chromatography-Mass Spectrometry (GC-MS). The final product of the thiosemicarbazone derivatives were tested for its antioxidant activity using the 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) method. In this study, the products obtained were benzaldehyde limonene thiosemicarbazone with a yield percentage of 58.18%, 4-hydroxybenzaldehyde limonene thiocarbazone with a yield percentage of 49.47%, vanillin limonene thiosemicarbazone with a yield percentage of 43.91%, and cinnamaldehyde limonene thiosemicarbazone with a yield percentage of 73.01%. The highest antioxidant ability was obtained by vanillin limonene thiosemicarbazone with an IC50 value of 108.8 ppm and the lowest antioxidant ability was obtained by benzaldehyde limonene thiosemicarbazone with an IC50 value of 177.2 ppm."

"Latar Belakang: Remineralisasi dentin dapat dicapai melalui beberapa metode, diantaranya secara Guided Tissue Remineralization (GTR) dalam sistem Polymer-Induced Liquid Precursor (PILP). Remineralisasi secara GTR terbukti dapat meremineralisasi affected dentin dengan membentuk mineral intrafibrillar dan ekstrafibrillar. Melalui sistem PILP, kristal terbentuk dengan ukuran kecil sehingga remineralisasi lebih banyak terjadi secara intrafibrillar. Penambahan fluor dalam sistem PILP diharapkan dapat membentuk kristal fluoroapatit yang berukuran lebih besar dan mampu menyempurnakan remineralisasi hingga ke ekstrafibrillar. Penelitian yang ada selama ini hanya berfokus pada permukaan dentin, sedengkan belum terdapat penelitian untuk membuktikan remineralisasi dengan penambahan fluor yang terjadi pada dinding tubulus dentin. Tujuan: Mengetahui pengaruh penambahan fluor 5ppm dan 25ppm dalam sistem PILP terhadap perubahan topografi dinding tubulus dentin dan persentase fluoroapatit. Metode: Sampel blok dentin terdemineralisasi direndam pada larutan remineralisasi dengan penambahan 5ppm dan 25ppm fluor. Sampel blok dentin kemudian akan dipotong lintang menggunakan metode fraktur lalu diamati dan dianalisis menggunakan uji FE-SEM dan XRD. Hasil: Terjadi perubahan topografi pada dinding tubulus dentin setelah dilakukan remineralisasi melalui proses PILPdengan penambahan 5ppm dan 25ppm fluor selama 14 hari yang dievaluasi secara deskriptif menggunakan FE-SEM. Hasil analisis XRD menunjukkan tidak ada perbedaan bermakna secara statistik penambahan fluor pada larutan remineralisasi PILP terhadap persentase fasa mineral fluoroapatit, namun secara substansi terjadipeningkatan persentase fluorapatit. Kesimpulan: Penambahan fluor dalam sistem PILP berpengaruh terhadap perubahan topografi dinding tubulus dentin dan persentasefluoroapatit.

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Background: Dentine remineralization can be achieved through several methods,

including Guided Tissue Remineralization (GTR) in the Polymer-Induced Liquid

Precursor (PILP) system. GTR remineralization has been shown to remineralize

affected dentin by forming intrafibrillar and extrafibrillar minerals. Through the PILP

system, crystals are formed with small sizes so that more remineralization occurs

intrafibrillarly. The addition of fluorine in the PILP system is expected to form larger

fluoroapatite crystals and be able to complete the remineralization to extrafibrillar. Existing research so far has only focused on the dentin surface, although there has been no research to prove remineralization with the addition of fluorine that occurs in the dentine tubule walls. Objective: To determine the effect of adding 5ppm and 25ppm fluorine in the PILP system on changes in the topography of the dentinal tubule walls and the percentage of fluoroapatite. Methods: Demineralized dentine block samples were immersed in remineralization solution with the addition of 5 ppm and 25 ppm fluorine. The dentine block samples will then be cross-sectioned using the fracture method and then observed and analyzed using the FE-SEM and XRD tests. Results: Topographical changes occurred in the dentinal tubule walls after remineralization through the PILP process with the addition of 5ppm and 25ppm fluorine for 14 days which were evaluated descriptively using FE-SEM. The results of the XRD analysis showed that there was no statistically significant difference in the addition of fluorine to the percentage of fluoroapatite mineral phase in the addition of fluorine to the percentage of fluoroapatite, but in substance there was an increase in the percentage of fluorapatite. Conclusion: The addition of fluorine in the PILP system affected the topography of the dentinal tubule walls and the percentage of fluoroapatite."

"Fluorine-doped tin oxide (FTO) is one of the conductive glasses that have strategic functions in various important applications, including dye-sensitized solar cell (DSSC). In the current work, the effects of deposition time (5, 10, 20, 30, and 40 minutes) upon the fabrication process of FTO thin film using spray pyrolysis technique with modified ultrasonic nebulizer has been studied in regard to its microstructural, optical, crystallinity, and resistivity characteristics. The variation was also performed by comparing the pure tin chloride precursor and the solution that was doped with fluor (F) at 2 wt% in order to see the doping effect on the properties of thin film. The thin films were characterized using x-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis) spectroscopy, and digital multimeter. On the basis of current investigation, it has been found that the best FTO was obtained through the pyrolysis technique of 20-minute deposition time, providing optical transmittance of 74%, a band gap energy (Eg) of 3.85 eV and sheet resistance (Rs) of 7.99 ?/sq. The fabricated FTO in the present work is promising for further development as conducting glass for dye-sensitized solar cell (DSSC)."

"This article provides a comprehensive review of the contamination by Butylin compounds (BTa) and its possible implications on the marine and coastal environments of the Philippines...."

"Telah dilakukan pengkajian tentang pengaruh pemberian fluorine terhadap strukturmikro fasa terpisah, dan sifat permukaan serta antarmuka poliuretan (PU). Fluorine dimasukkan ke bagian segmen lunak PU. Struktur fasa terpisah diuji dengan X-ray diffraction and a small angle X-ray scattering. Sedangkan sifat permukaan dan antarmuka dikarakterisasi dengan X-ray photoelectron spectroscopy adan sudut kontak dinamis. Daya rekat juga telah diinvestigasi dengan metode cross-cut tape test dan peel test. Hasil penelitian menunjukkan adanya lokalisasi fluorine di permukaan tanpa ada perubahan yang nyata pada strukturmikro fasa terpisah PU. Dari hasil penelitian juga diketahui bahwa sifat pelepasan PU meningkat seiring dengan kandungan fluorine. Hasil-hasil dari penelitian ini menunjukkan dengan nyata bahwa strukturmikro fasa terpisah dan sifat permukaan PU dapat dikontrol dengan mengatur kandungan fluorine yang dimasukkan ke dalam segmen lunak."