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"ABSTRAKKaries gigi masih menjadi masalah kesehatan gigi di Indonesia, sehingga pencegahan menjadi penting. Email gigi merupakan lapisan terluar gigi yang berperan dalam ketahanan gigi terhadap penyebab karies. Biji Kakao Sulawesi Tengah merupakan bahan alam hasil perkebunan unggulan Indonesia, mengandung senyawa alkaloid yang berpotensi meningkatkan ketahanan host email gigi . Penelitian ini merupakan studi biomimetika eksperimental laboratorik in vitro, yang mencakup identifikasi karakteristik senyawaan alkaloid biji kakao klon Sulawesi-1 S1 dan Sulawesi-2 S2 asal Sulawesi Tengah untuk mendapatkan prototype biomimetika, uji khasiat formula alkaloid pada email gigi berupa uji kekerasan email gigi, karakteristik permukaan dan kristal apatit email, serta uji karakteristik permukaan email setelah proses demineralisasi dan remineralisasi email gigi. Hasil penelitian menunjukkan bahwa senyawaan alkaloid klon biji kakao klon S1 dan S2 asal Sulawesi Tengah teridentifikasi mengandung Teobromin T , Teofilin TF dan Kafein K , dengan komposisi T : TF : K = 6 : 1 : 1 untuk S1 dan T : TF : K = 4 : 1 : 1 untuk S2. Formula alkaloid biomimik S1 lebih bermakna dalam meningkatkan kekerasan mikro email gigi dibandingkan S2. Formula alkaloid biomimik S1 dapat mempengaruhi karakteristik permukaan dan meningkatkan derajat kristalinitas apatit email gigi, serta berkhasiat terhadap remineralisasi email gigi. Dengan demikian alkaloid biji kakao Sulawesi Tengah dalam bentuk formula biomimik, berpotensi sebagai alternatif agen remineralisasi email gigi.

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ABSTRACTDental caries is still a major dental health problem in Indonesia, and preventive measures needs to be done to resolve it. The enamel is the outermost layer of teeth in which play a role in resistance to the cause of dental caries. Central Sulawesi cacao beans are natural materials featured Indonesian plantation crops, contains the alkaloid compounds that could potentially increase the resistance of the host the enamel . The research was a biomimetic study laboratory experiment in vitro, which covered identification of the characteristics of cacao beans s alkaloid compounds of clones Sulawesi 1 S1 and Sulawesi 2 S2 from Central Sulawesi, to obtain biomimetics prototype, to test the efficacy of the alkaloid formula to tooth enamel i.e. enamel microhardhess, surface and apatite crystal characteristics test, and also enamel surface characteristics test after demineralization and remineralization process of tooth enamel. The results of this research showed that the cacao beans s alkaloid compounds of clones S1 and S2 from Central Sulawesi contains Theobromine T , Theophylline TF and Caffeine K , with composition T TF K 6 1 1 for S1 and T TF K 4 1 1 for S2. The S1 biomimic alkaloid formula was more significant in increasing tooth enamel microhardness than S2. S1 biomimic alkaloid formula affected the characteristics of the surface and increased the degree of apatite crystallinity of tooth enamel, as well as efficacious against the remineralization of tooth enamel. Thus Central Sulawesi cacao beans alkaloid in the form of biomimic formula, have potential as an alternative remineralization agents of tooth enamel."

"Elektrokatalis OER merupakan komponen penting dalam penyimpanan energi, konversi energi, dan elektrolisis air. Penelitian ini bertujuan untuk mendapat elektrokatalis berbasis BaFe12O19 (BHF) dan BaTiO3(BTO) terdoping nikel dengan komposit polianilina. Material elektrokatalis BaFe12O19 terdoping Ni dibuat melalui teknik kopresipitasi pada suhu 4oC dengan suhu sintering 750oC. Material BaTiO3 terdoping Ni dibuat melalui teknik sinter berbantuan hidrotermal tekanan rendah. Komposit BHF dengan polianilina (PANI) dan BTO dengan polianilina dilakukan dengan teknik polimerisasi in situ. Berdasarkan pengukuran XRD, diperoleh BHF fase tunggal dan ada pengotor Fe2O3 pada BHF terdoping Ni (BHFNi) dan kompositnya dengan PANI. Doping Ni dan komposit PANI meningkatkan volume unit sel dari BHF. BTO fase tunggal diperoleh pada suhu sinter 800oC selama 2 jam, sedangkan pada BTO doping Ni terdapat fase BaCO3 dan pada komposit PANI terdapat pengotor BaSO4. Kinerja elektrokatalis Oxygen Evolution Reaction (OER) dalam medium NaOH meningkat dengan adanya doping Ni dan komposit polianilina pada BHF dan BTO. Campuran BHFNi-BTONi-PANI (25:75) menunjukkan kinerja elektrokatalis OER terbaik dalam medium NaOH berdasarkan parameter nilai densitas arus dan potensial berlebihnya. Sistem redoks Ni3+/2+, Fe4+/3+, Ti4+/3+ dan sistem lokalisasi elektron dalam PANI menjadi faktor yang mempengaruhi kinerja OER yang baik.

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Oxygen Evolution Reaction (OER) electrocatalyst is an important component in energy storage, energy conversion and electrolysis of water. This study was aimed to obtain oxygen evolution reaction electrocatalyst based on BaFe12O19 (BHF), BaTiO3 (BTO), Ni-doped BaFe12O19 (BHFNi), and Ni-doped BaTiO3 (BTONi), and its composite with polyaniline. Electrocatalyst of BHF and BHFNi were synthesized by co-precipitation at 4oC with sintering temperature of 750oC. BTO and BTONi were prepared through a low pressure hydrothermal assisted sintering technique. the polyaniline composites were carried out by in situ polymerization at 0-4oC. A single phase BHF was obtained on undoped BHF, and Fe2O3 impurities were presence on BHFNi and its composite with PANI. Ni doping decrease on cell unit volume of BHF, while PANI composite increases cell unit volume of BHF. Single phase BTO was obtained through sintering at 800oC during 2 hours, while BaCO3 phase was appeared on Ni-doped BTO and BaSO4 was appeared on its PANI composite.

Based on overpotential and charge transfer coefficient, BHF and BTO performances as OER electrocatalytic in the NaOH medium were increased with present nickel and composite of polyaniline. The mixture of BHFNiPANI-BTONiPANI (25:75) shows the best performance of OER electrocatalyst in NaOH medium based on the parameters of current density and overpotential. The Ni3+/2+, Fe4+/3+, Ti4+/3+ redox systems and the electron localization system in PANI are factors that influence the good performance of there OER electrocatalysts"

"Riset polimerisasi kationik minyak sawit berbantuan gelombang mikro belum pernah dilakukan. Dalam penelitian ini, minyak sawit dan hasil olahannya dipolimerisasi kationik dengan katalis borontriflorida eteral berbantuan gelombang mikro menggunakan oven gelombang mikro komersial. Komposisi bahan baku prekursor dianalisis menggunakan kromatografi gas. Bilangan iodin, gugus fungsi, serapan ultraviolet prekursor dan produk polimerisasinya dianalisis masing-masing dengan titrimetri, dan spektrofotometri inframerah Transformasi Fourier dan spektrofotometri ultraviolet. Pemindaian kalorimetrik diferensial (DSC) digunakan untuk mengamati ciri termal polimer yang terbentuk. Proses inklusi urea terhadap minyak sawit meningkatkan komponen asam lemak tak jenuh seperti yang ditunjukkan oleh peningkatan fraksi asam lemak tidak jenuh, bilangan iod, intensitas penyerapan pita alkena dalam spektrum inframerah, dan absorbansi spektrum ultraviolet. Polimerisasi kationik minyak sawit terkatalisis borontrifluorida eteral menghasilkan padatan. Pembentukan polimer mengubah gugus C=C menjadi C-C, hal ini ditunjukkan dengan menurunnya bilangan iodin dari produk polimer yang dihasilkan dan menurunnya intensitas pita alkena pada bilangan gelombang 3025 cm-1 (regang =C-Hcis, 1654 cm-1 dan 1648 cm-1 (regang C=C), dan 723 cm-1 (tekuk -HC=CH-) pada spektrum inframerah. Disamping itu terjadi reaksi isomerisasi cis-trans yang ditunjukkan munculnya serapan pada bilangan gelombang 968 cm-1 (regang C=C trans). Kurva termogram DSC membuktikan bahwa produk polimerisasi adalah polimer termoplastik dan memerlukan perlakuan curing. Perlakuan panas dapat menyebabkan deformasi polimer yang terbentuk, yang ditunjukkan oleh penurunan bilangan iod, penurunan serapan ultraviolet dan perubahan serapan inframerah serta kurva termogram DSC. Kopolimerisasinya bersama divinyil benzena menghasilkan polimer termoset.

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Microwave assisted cationic polymerization of palm oil study has never been done yet. In this study, palm oil, and processed products have been cationic polymerized with borontrifluoride-etheral catalyst under microwave irradiation using commercial microwave ovens. The composition of the feedstock was analyzed with gas chromatography. Iodine number, functional groups, ultraviolet absorption of precursor and the polymerization products were analyzed respectively by titrimetry, and Fourier transform infrared spectrophotometry and ultraviolet spectrophotometry. Differential Scaning Calorimetric (DSC) is used to observe the thermal characteristics of polymers. The process of inclusion of Urea to palm oil increases the component of unsaturated fatty acids as indicated by the increase in the fraction of unsaturated fatty acids, iodine numbers, the intensity of alkene band absorption in the infrared spectrum, and the absorbance of the ultraviolet spectrum. The cationic polymerization of oil palm catalyzed by borontrifluoride etheral produces solids. The formation of the polymer converts the C=C group to C-C, this is indicated by the decrease of the iodine number of the resulting polymer product and the decrease of the intensity of the alkene band at wave number 3025 cm-1 (streching =C-Hcis), 1654 cm-1 and 1648 cm (streching C=C), and 723 cm-1 (bending -HC=CH-) in the infrared spectrum. The other process was cis-trans isomerization reaction showed absorption band at wave number 968 cm-1 (streching C=Ctrans. The DSC thermogram curve proves that polymerization products are thermoplastic polymers and require curing treatment. The heat treatment can cause the deformation of the formed polymer shown by changes in iodine number, infrared absorption spectrum, ultra-violet absorption spectrum and DSC thermogram curve. Copolymerization with divinyl benzene produces thermoset polymers."

"ABSTRAKKajian agen antikaries propolis Trigona spp. telah dilakukan dengan pendekatan analisis kimia dipandu dengan bioassay. Metode ekstraksi berbantuan gelombang mikro (MAE) paling efisien dibanding metode maserasi dan refluks. Profil kimia EEP menunjukkan komposisi kimia yang kompleks dan didominasi oleh komponen dengan kepolaran rendah. Fraksi kloroform merupakan fraksi potensial sebagai agen anti karies dengan karakteristik: MIC = 50 ? 100 g/ml, MBC = 400 ? 800 g/ml, adherence = 6,02% (penurunan sekitar 60% relatif terhadap media tanpa fraksi kloroform), dan dengan komposisi kimia didominasi oleh senyawa bernitrogen.

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ABSTRACTStudy of anticaries agents in propolis Trigona spp. has been done using bioassayguided chemical analysis approach. The microwave-assisted extraction (MAE) was the most efficient compared to maceration and reflux methods. Chemical profile of EEP showed a complex chemical composition and dominated by low polarity components. The fraction of the chloroform has a potential as an anticaries agent with its characteristics as follows: MIC = 50 ? 100 g/ml, MBC = 400 ? 800 g/ml, adherence characteristic = 6.02% (approximately 60% decrease relative to the media without chloroform fraction) and its chemical composition dominated by nitrogenous compounds."

"ABSTRAKDalam masa perawatan ortodontik, kejadian lepasnya breket sering terjadi sehinggadiperlukan metode pembersihan yang cepat, efektif dan ekonomis. Hal terpenting adalahkarakter breket yang lepas setelah dibersihkan, kualitas tidak berubah sehingga dapatdipasang kembali. Penelitian ini bertujuan untuk mendapatkan sistem pelarut yang dapatmelepas bahan adesif dari basis breket metal berbasis solvolis tanpa mengubahkarakteristik breket metal dan lebih efektif dibandingkan metode yang umum digunakanyaitu sandblasting dan pembakaran. Penelusuran sistem pelarut melibatkan berbagaijenis pelarut dan faktor pendukungnya: termal, katalis dan surfaktan. Kinerja pelepasanbahan adesif dipantau dengan uji Shear Bond Strength SBS pada gigi Reused dan gigibaru, pengamatan topografi permukaan dan komposisi dengan Scanning ElectronMicroscopy SEM dan Electron Dispersive X-ray Spectroscopy EDAX sertagambaran sisa bahan adesif dengan Modifikasi Adhesive Remnant Index ARI .Spesimen penelitian terdiri atas tujuh puluh breket metal Stainless Steel Mini DynaLock dan seratus gigi Premolar satu dengan adesif Transbond XT. Hasil penelusurandiperoleh sistem pelarut dengan susunan pelarut organik N-Methyl-2-Pyrrolidone,katalis Zn Asetat, surfaktan Triton X-100 dan gelombang mikro. Uji Two Way Anovadari nilai SBS sandblasting, pembakaran dan solvolisis menunjukkan perbedaanbermakna p

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ABSTRACTDuring orthodontic treatment, the bracket loose often occurs so that a fast, effective andeconomical cleaning method is needed. The most important thing is the character of thecleaned bracket, the quality does not change so it can be reinserted. The objective of thisresearch is to find a solvent that can remove adhesive material from base metal bracketwithout changing the metal bracket characteristics and more effective than commonlyused method i.e. sandblasting and burning. The search for a solvent system involvesvarious types of solvents and their supporting factors thermal, catalyst and surfaceagent. The adhesive release was monitored by Shear Bond Strength SBS test onreused tooth and new tooth, surface topography observation and composition withScanning Electron Microscopy SEM and Electron Dispersive X Ray Spectroscopy EDAX as well as an overview of residual adhesive with Modified Adhesive RemnantIndex ARI . The study specimens consisted of seventy metal brackets of Stainless SteelMini Dyna Lock and one hundred first Premolar teeth with Transbond XT adhesives.The result of this research is the solvent system with organic solvent N Methyl 2 Pyrrolidone, catalyst Zn Acetate, surfactant Triton X 100 and microwave. Two wayAnova Test of SBS sandblasting, burning and solvolysis values showed significantdifferences p "