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Abstrak :
ABSTRAK
The interaction of cationic surfactant (CTAB, Cationic surfactant hexadecyl trimethyl ammonium bromide ((C₁₆H₃₃)N(CH₃)₃BR and TTAB, Tetradecyl trimethyl ammonium bromide ( )), a prevalent chemical in the industrial and natural processes, with water ( ) has been studied using GROMACS program and VMD program. In the following project, to simulate the CTAB and TTAB at air-water interface, GROMACS (Groningen Machine for Chemical Simulations) software is used. GROMACS is a molecular dynamics package designed for primary use of simulation of biochemical molecules like proteins, lipids, and nucleic acids that have a many complicated bonded interactions (GROMACS, 2010). Furthermore, to model and display the simulation, VMD (Visual Molecular Dynamics) program is used. VMD is intended for modeling, visualization and analysis of biological systems such as proteins, nucleic acids, lipid bilayer assemblies, etc. In this research project 13 simulations, 6 of these are successive simulations and the other 7 simulations have been included in the appendix. The simulations have been simulated to prove the following 3 hypotheses which are ssurfactants has an amphiphilic nature, surfactants adsorb on the interface between oil and water, lowering the interfacial tension and promoting mixing and surface potential measurement at the air-water interface increases surfactant-dependent manner in the air-water expanded transition region. Therefore with the addition of surfactant to the air-water interface, there will be a sudden increase of surface potential. The first seven simulations that have been included in the appendix were simulated to find the right charge distribution. All the observed results shown by these 13 simulations are not yet predictable or reliable; this is due to not the right amount of simulation time or the charge distribution of the cationic surfactant. The three kinds of observations (the density profile of the cationic surfactant, the surface tension of the cationic surfactant with water, and the surface potential of cationic surfactant with water) are very uncertain and therefore many more simulations are required to be completed in the future.

Abstrak :
Penelitian keragaman genetik tanaman buah merupakan salah satu kegiatan penting untuk mendukung pemuliaan tanaman. Perbedaan tanaman dapat dideteksi melalui beberapa penanda, antara lain dengan pola pita DNA (Lamadji 1998) yang sering disebut sebagai penanda molekuler....

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Modifikasi perlu dilakukan pada CNT agar dapat digunakan dalam aplikasi penghantar obat. Modifikasi permukaan CNT dilakukan dengan surfaktan CTAB dan minyak zaitun. Tahapan modifikasi CNT melalui sonikasi, pencucian, pengeringan, hingga karakterisasi. Variasi yang digunakan pada CNT-CTAB adalah 100mg CNT dengan penambahan 80, 90, 100, 110, dan 120mg CTAB. Sedangan variasi untuk CNT-minyak zaitun adalah 100mg CNT dengan 60, 80, 100, 120, dan 140ml minyak zaitun. Setelah tahap sonikasi, kecenderungan CNT untuk beragregasi dapat menurun dan mampu terdispersi lebih stabil. Hal ini ditunjukkan dari hasil Zeta Potensial (ZP) CNT-CTAB dan CNT-minyak zaitun yang memiliki nilai ZP lebih tinggi dari CNT murni. CNT-CTAB dan CNTminyak zaitun juga dapat terdispersi 68 jam lebih stabil dibandingkan CNT murni. Setelah sampai pada tahap akhir modifikasi, melalui uji SEM dihasilkan CNTCTAB dan CNT-minyak zaitun dengan morfologi permukaan yang tidak mengalami kerusakan secara struktural dan telah berhasil memecah partikel CNT hingga memiliki ukuran diameter 31% lebih kecil. Berdasarkan hasil EDX, CNTCTAB dan CNT-minyak zaitun menunjukkan sifat hidrofilik dengan meningkatnya persentase massa unsur O sebesar 137%. Selain itu, unsur Ni sebagai pengotor yang bersifat toksik juga mengalami penurunan rata-rata 68%. Interaksi antara gugus kepala surfaktan CTAB (N+) dengan permukaan CNT yang terjadi pada panjang gelombang 1221 cm-1 (C-N). Sedangkan gugus hidroksil muncul pada CNT-minyak zaitun pada 2340 cm-1. Kondisi optimum untuk modifikasi dengan CTAB adalah CNT-110mg CTAB dan untuk minyak zaitun adalah CNT-120ml minyak zaitun. ......Modification is needed on CNTs to be used in drug delivery applications. CNT surface modification with CTAB surfactant and olive oil. Stages of CNT modification through sonication, washing, drying, to characterization. The variation used in CNT-CTAB is 100mg CNT with the addition of 80, 90, 100, 110, and 120mg CTAB. The variation for CNT-olive oil is 100mg CNT with 60, 80, 100, 120, and 140ml olive oil. After the sonication stage, tendency of CNTs to aggregate may decrease and be dispersed more stable. The result of Zeta Potensial (ZP) CNT-CTAB and CNT-olive oil which has a higher ZP value than pristine CNT. CNT-CTAB and CNT-olive oil can also dispersed 68 hours more stable than pristine CNT. At the final stages of modification, SEM tests are produced by CNT-CTAB and CNT-olive oils with undamaged surface morphology and have succeeded in breaking CNT particles into 31% smaller diameter sizes than pristine CNT. Based on the EDX results, CNT-CTAB and CNT-olive oil exhibit hydrophilic properties with the mass saving element of 137% O. In addition, the Ni element as a continuous toxic impurities also decreases 68%. The interaction between the CTAB surfactant head group (N +) with the CNT surface occurring at a wavelength of 1221 cm-1 (C-N). While the hydroxyl group appears on the CNTolive oil at 2340 cm-1. The optimum condition for modification with CTAB is CNT-110mg CTAB and for olive oil is CNT-120ml olive oil.

Abstrak :
Penggunaan bahan bakar fosil yang berlebihan disertai dengan degradasi lingkungan yang terjadi dalam beberapa dekade terakhir, menghadirkan Fatty acid monoalkyl ester atau biodiesel sebagai salah satu sumber bahan bakar mesin diesel yang sustainable. Limbah minyak goreng merupakan salah satu pilihan tepat untuk menjadi prekursor utama dari biodiesel ini dengan asam laurat sebagai penyumbang komposisi asam lemak terbesar didalamnya. Asam laurat ini dapat diesterifikasi membentuk metil laurat  dengan bantuan katalis asam heterogen salah satunya adalah Metal Organic Frameworks (MOF) berbasis zirconium (Zr) dengan ligan BDC atau dikenal luas sebagai UiO-66. Semakin berjalannya waktu, kebutuhan akan peningkatan efektifitas dari katalis semakin besar sehingga ditemukan suatu cara meningkatkan aktivitas katalisis dari MOF salah satunya dengan cara penambahan suatu surfaktan capping agent seperti Cetyltrimethylammonium bromide (CTAB) ke dalam campuran sintesis. Pada penelitian ini, hasil karakterisasi volume pori akumulatif variasi UiO66 menunjukkan peningkatan yang signifikan yaitu dari tanpa penambahan (0,7199 cc/g) ke penambahan CTAB sebanyak 0,5 ekivalen (0,7312 cc/g). Meski luas permukaan BET menurun dari 1202.855 m²/g (tanpa CTAB) ke 1178.861 m²/g (dengan CTAB 0,5 ekivalen) performa katalisasi lebih baik pada UiO66 dengan penambahan CTAB 0,5 ekivalen dengan persen konversi sebesar 29,41% dan kadar methyl laurat sebesar 57,02% dibandingkan dengan UiO66 tanpa penambahan CTAB dengan persen konversi sebesar 29,01% dan kadar methyl laurat sebesar 45,04%. Secara keseluruhan, performa dari katalis UiO66 untuk mengkatalisasi reaksi esterifikasi asam laurat menjadi metil laurat lebih baik seiring dengan ditambahkannya CTAB pada saat sintesis. ......The excessive use of fossil fuels and environmental degradation that occurred in recent decades, has triggered the discovery of fatty acid monoalkyl ester as one of the sustainable source for diesel fuel. Waste cooking oil is preferably used to be the main precursor with lauric acid as the largest contributor to the fatty acid composition in it. lauric acid can be esterified to form methyl laurate with a presence of heterogeneous acid catalysts, which Metal Organic Frameworks (MOF) based on zirconium (Zr) with BDC ligand or widely known as UiO66 that playing role as one of the best of a kind. Hereinafter, the need to increase the effectiveness of the catalyst is getting further so that the addition of capping agent such as CTAB is found as an interesting procedure to be applied at. In this study, CTAB is added to the process with the results as the significant grow of accumulative pore volume  from 0,7199 cc/g (without the addition of CTAB) to 0,7312 cc/g (with the addition of 0,5 equivalent CTAB). Although the surface area of  BET decreased from 1202,855 m²/g (without CTAB) to 1178,861 m²/g (with CTAB 0.5 equivalent) the catalyst performance was better on UiO66 with the addition of CTAB 0.5 equivalent with a conversion percentage 29.41% and methyl laurate content 57.02%. This number is bigger compared to to UiO66 without the addition of CTAB with a conversion percentage 29.01% and methyl laurate content 45.04%. Overall, the performance of the UiO66 catalyst in this esterification reaction of lauric acid to methyl laurate was better with the addition of CTAB during the synthesis.

Abstrak :
ABSTRAK
Nanostruktur TiO2 sebagai semikonduktor memiliki sifat-sifat unggul yang menjadikannya menarik untuk diteliti dan dikembangkan hingga sekarang. Sintesis dari nanostruktur TiO2 telah dilakukan pada penelitian ini dengan teknik presipitasi menggunakan prekursor TiOSO4.xH2O dan template kombinasi surfaktan P123 dan CTAB. Variabel yang diteliti berupa jenis pelarut yang digunakan untuk membuat larutan precursor (air dan ethanol), perlakuan hidrotermal, dan temperatur kalsinasi (200 dan 400 oC) yang bertujuan untuk menginvestigasi pengaruhnya terhadap kristalinitas fasa dan ukuran kristalit dari nanostruktur TiO2 yang dihasilkan. Karakterisasi dilakukan menggunakan XRD, TEM, dan UV-Vis. Hasil yang didapatkan menunjukkan parameter terbaik dalam sintesis nanostruktur TiO2 adalah dengan menggunakan pelarut air suling dalam pembuatan larutan prekursor, perlakuan hidrotermal untuk metode sintesisnya, dan temperatur kalsinasi 400 oC dimana didapatkan nanostruktur TiO2 dengan fasa anatase yang memiliki ukuran kristalit mencapai 8,02 nm. Hasil nanostruktur yang diperoleh ini menjanjikan untuk dipakai dalam aplikasi sel surya tersensitasi zat pewarna dan fotokatalisis.

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ABSTRACT
TiO2 nanostructure as semiconductor has distinguished properties that makes this material attractive to be studied and developed up until now. In this study, synthesize of TiO2 nanostructure was carried out by precipitation technique, using TiOSO4.xH2O as precursor and combination of P123 and CTAB surfactant as template. Variables investigated were solvent for preparing precursor solution (distilled water and ethanol), hydrothermal treatment, and calcination temperature (200 and 400 oC), which were aimed to investigate their effects of phase cristallinity and crystallite size of TiO2 nanostructure. Characterizations were performed by using XRD, TEM, and FTIR. The results showed that the best parameters in synthesizing TiO2 nanostructure are by using distilled water as solvent for preparing precursor solution, hydrothermal treatment for the synthesize method, and calcination temperature of 400 oC which successfully obtained nanostructure TiO2 with anatase phase and its crystallite size reached 8,02 nm. The obtained TiO2 nanostructure promises to be used in dye sensitized solar cell and photocatalytic applications.

Abstrak :
Nanopartikel ZnO didop Cr disintesis menggunakan metode kopresipitasi untuk empat variasi konsentrasi Cr. Karakteristik nanopartikel dipelajari menggunakan Energy Dispersive X-Ray (EDX), X-Ray Difraction (XRD), Electron Spin Resonance (ESR), Field Emision - Scanning Electron Microscope (FESEM), Fourier Transform-Infrared (FTIR), and spektroskopi Ultra Violet- Visible (UV- Vis). Uji aktivitas nanopartikel diukur melalui degradasi Methyl Orange (MO) dan Methylene Blue (MB) pada daerah sinar Ultraviolet (UV). Hasil menunjukkan keberadaan Cr dan cetyltrimethylammonium bromide (CTAB) dalam sistem ZnO nanopartikel. Nanopartikel yang dihasilkan berfase tunggal dengan struktur heksagonal wurtzite dan mempunyai bentuk spherical-like. Peningkatan konsentrasi dopan Cr dan kehadiran surfaktan kationik CTAB menyebabkan berkurangnya celah energi dan lebih lanjut lagi meningkatkan aktivitas fotokatalitik. Kehadiran surfaktan kationik CTAB menyebabkan nanopartikel ZnO didop Cr lebih efektif dalam mendegradasi zat pewarna anionik MO dibanding kationik MB. ...... Cr doped ZnO nanoparticles were synthesized by coprecipitation methods with four variation Cr concentrations. The nanoparticles were characterized by using Energy Dispersive X-Ray (EDX), X-Ray Difraction (XRD), Electron Spin Resonance (ESR), Field Emision - Scanning Electron Microscope (FESEM), Fourier Transform-Infrared (FTIR), and UltraViolet-Visible (UV-Vis) Spectroscopy. The photocatalytic activity of nanoparticles were evaluated by measuring degradation of Methyl Orange (MO) and Methylene Blue (MB) in Ultraviolet (UV) region. The results confirmed the presence of Cr dopant and cationic surfactant cetyltrimethylammonium bromide (CTAB) in the ZnO nanoparticles system. The resulting nanoparticles have single-phases with hexagonal wurzite structures and spherical-like shapes. Increasing the Cr dopant concentrations and the presence of cationic surfactant CTAB cause a reduction in energy gap and more futher improve the photocatalytic activity. The presence of cationic surfactant CTAB causes the Cr doped ZnO nanoparticles were more effective in degrading MO anionic dyes than MB cationic dyes.

Abstrak :
Kemampuan adsorpsi pada silika mesopori dapat dimanfaatkan sebagai bahan penyerapan limbah zat warna pada industri tekstil. Namun, bahan baku prekursor TEOS dan TMOS untuk sintesis silika mesopori relatif mahal. Oleh karena itu, tongkol jagung dengan kandungan silika yang cukup tinggi dapat dijadikan alternatif bahan prekursor silika yang murah dan mudah didapat. Pada penelitian lain, sintesis silika mesopori dengan tongkol jagung sudah berhasil dilakukan. Untuk meningkatkan karakteristik silika mesopori dilakukan modifikasi jenis dan variasi rasio surfaktan. Sehingga pada penelitian ini dilakukan sintesis silika mesopori menggunakan bahan baku tongkol jagung dengan variasi rasio Pluronic 123 dan cetrimonium bromide sebagai template pori. Variasi rasio Pluronic 123/cetrimonium bromide yang digunakan pada penelitian ini adalah 1:0; 1:3; 1:1 dan 3:1 yang akan menghasilkan karakteristik silika mesopori dan daya serap terhadap zat warna yang berbeda. Adsrobat yang digunakan pada penelitian ini adalah zat warna kationik yaitu methylene blue dan brilliant green serta zat warna anionik yaitu methyl orange. Kemudian untuk jenis pengujian yang dilakukan pada penelitian ini adalah SAXS, SEM, FTIR, BET, dan UV-Vis. Dimana sintesis silika mesopori yang dihasilkan memiliki luas permukaan sebesar 127 m2/g – 425 m2/g dengan kapasitas adsorpsi sebesar 7,47 mg/g – 9,84 mg/g pada zat warna kationik dan 0,67 mg/g – 1,3 mg/g pada zat warna anionik. Silika mesopori dengan luas permukaan dan kapasitas adsorpsi tertinggi dimiliki oleh silika mesopori dengan rasio Pluronic 123/ cetrimonium bromide 1:1. Selain itu diketahui bahwa silika mesopori lebih efektif untuk mengadsorpsi zat warna kationik dibandingkan zat warna anionik. ......The adsorption ability of mesoporous silica can be used as an adsorben for dye waste in the textile industry. However, the raw materials of precursor, such as TEOS and TMOS are relatively expensive. Therefore, corn cobs which have a fairly high silica content can be used as a cheap and easy-to-obtain alternative for silica precursor material. In another study, the synthesis of mesoporous silica with corn cobs has been successfully carried out. To improve the characteristics of mesoporous silica, modification of the type and variation of surfactant ratio was conducted. Therefore, in this study, mesoporous silica was synthesized using corn cobs as raw material with various ratios of Pluronic 123 and cetrimonium bromide as a pore template. Variations in the ratio of Pluronic 123/cetrimonium bromide used in this study were 1:0; 1:3; 1:1 and 3:1 which will produce different mesoporous silica characteristics and absorption capacity toward dyes. The adsorbate used in this study was a cationic dye, namely methylene blue and brilliant green, and an anionic dye, methyl orange. Then for the types of tests carried out in this study are SAXS, SEM, FTIR, BET, and UV-Vis. Where the resulting mesoporous silica synthesis has a surface area of 127 m2/g – 425 m2/g with an adsorption capacity of 7.47 mg/g – 9.84 mg/g on cationic dyes and 0.67 mg/g – 1.93 mg/g on anionic dyes. . Mesoporous silica with the highest surface area and adsorption capacity is owned by mesoporous silica with Pluronic 123/cetrimonium bromide ratio of 1:1. In addition, it is known that mesoporous silica is more effective in adsorption of cationic dyes than anionic dyes

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Perkembangan teknologi pendinginan sangat berpengaruh terhadap hasil dari perlakuan panas yang dilakukan pada sebuah material. Media pendingin yang efektif dinilai mampu menghasilkan kecepatan pendinginan yang cepat sehingga dapat menghasilkan baja dengan kekerasan yang tinggi. Penelitian ini bertujuan untuk memanfaatkan grafit dan oli 5W-40 untuk membuat nanofluida sebagai media pendingin. Grafit yang digunakan terlebih dahulu digerus sebelum dicampurkan dengan oli 5W-40. Pada penelitian ini juga dilihat pengaruh dari penambahan surfaktan berupa sodium dodecylbenzenesulfonate (SDBS), cetyltrimethylammonium-bromide (CTAB), dan polyethylene glycol (PEG) untuk membandingkan efektivitas nanofluidanya. Konsentrasi grafit yang digunakan juga beragam, yaitu 0.1%w/v, 0.3%w/v, dan 0.5%w/v sehingga dapat dilihat pengaruh yang dihasilkan dari perubahan konsentrasi tersebut. Berdasarkan hasil penelitian, didapatkan bahwa penambahan surfaktan dapat meningkatkan nilai konduktivitas termal dari nanofluidanya. Diketahui bahwa penambahan CTAB dengan konsentrasi partikel 0.1%w/v menghasilkan nanofluida dengan nilai konduktivitas tertinggi, yaitu 0.173 W/mK. Sementara itu, kekerasan baja tertinggi dihasilkan oleh nanofluida dengan penambahan PEG dan konsentrasi partikel 0.1%w/v, yaitu sebesar 38 HRC dan diikuti oleh nanofluida dengan penambahan CTAB dan konsentrasi partikel 0.1%w/v, yaitu sebesar 36 HRC. Hal ini disebabkan karena adanya mekanisme penyerapan yang berbeda-beda dari surfaktan pada lingkungan yang berbeda. ...... The development of quenching technology will highly influence the results of materials’ heat treatment process. An effective quenchant obtained fast cooling rate during the quenching process so that the steel’s hardness increased. This study aims to utilize graphite as nanoparticles and 5W-40 engine oil as the base fluid to make a nanofluid quenchant. The graphite was being milled before mixed with the oil. This study also studied the effect of surfactants addition in the form of sodium dodecylbenzenesulfonate (SDBS), cetyltrimethylammonium-bromide (CTAB), and polyethylene glycol (PEG) to compare the effectiveness of the nanofluids. The graphite concentration varies as well, namely 0.1%w/v, 0.3%w/v, and 0.5%w/v to see the effect resulting from the change in concentration. Based on the results of the study, it was found that the addition of surfactants affects the nanofluids’ thermal conductivity sufficiently. It is known that the addition of CTAB with particle concentration of 0.1%w/v produces the highest conductivity value, which is 0.173 W/mK. Meanwhile, the highest steel hardness was produced by nanofluid with the addition of PEG with particle concentration of 0.1%w/v, which was 38 HRC and followed by nanofluid with the addition of CTAB with particle concentration of 0.1%w/v, which was 36 HRC. The discrepancy happened because of the surfactants’ different absorption mechanism in different environments.

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ABSTRAK
As of present, water pollution that is caused by textile dyeing factories is one of the primary concerns in Thailand. wastewater is contaminated with dyes, which results in an unpleasant watercolor. this research emphasized on the study of the adsorption of Direct Red 83 dye through the use of water hyacinths, which are abundant in number and can be easily obtained. prior to the adsorption, water hyacinths were modified with cetyltrimetylammonium bromide (CTAB). The value of pHpzc of the adsorbent was 5.15. The adsorption was most effective at the pH value of 3. After increasing the amount of adsorbent and the temperature for water treatment, the percentage of dye removal would increase. However, if the concentration of dye increases, the percentage of dye removal would decrease. Upon the addition of electrolytes into the Wastewater that contained this particular type of dye, it was found that calcium salts lowered the percentage of dye removal to a greater extent than sodium salts. The process of adsorption was in accordance with Langmuir adsorption model, with qe value equals to 66.2252 milligrams per gram, KL value equals to 1.6064 liters per milligram, and RL value equals to 0.0062. based on Dubinin-Radushkevich equation, the obtained E value represents physical adsorption. According to Redlich-Peterson equation, bR equals to 1.0797, which supported the fact that adsorption conformed to Langmuir model. This adsorption was in accordance with the model of a second-order reaction. When the temperature of the Wastewater increases, K2 value would increase. when the concentration of dye increases, qe value would increase.

Abstrak :
Nanopartikel ZnO yang dimodifikasi oleh CTAB dan didop dengan empat variasi konsentrasi atom Ni berhasil dibuat melalui metode kopresipitasi. Seluruh sampel dikarakterisasi oleh pengukuran energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy, electron spin resonance (ESR), field emission scanning electron microscope (FESEM), dan UV-Vis spectrophotometry. Hasil pengukuran memperlihatkan bahwa penambahan CTAB dan konsentrasi atom dopant mempengaruhi morfologi dan sifat optik dari seluruh sampel. Pengujian aktivitas fotokatalitik sampel dilakukan pada larutan methyl orange (MO) dan methylene blue (MB) di bawah paparan sinar UV selama 2 jam. Hasil yang diperoleh menunjukkan bahwa efisiensi kinerja degradasi fotokatalitik dari sampel meningkat seiring dengan bertambahnya konsentrasi atom dopant. ...... CTAB-modified ZnO nanoparticles doped with four different concentrations of Ni were successfully synthesized by co-precipitation method. All samples were characterized using energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy, electron spin resonance (ESR), field emission scanning electron microscope (FESEM), and UV-Vis spectrophotometry. The results demonstrated that the addition of CTAB and doping concentration affect the morphology and optical properties of the samples. The photocatalytic activity test of all samples was studied by observing the degradation of methyl orange (MO) and methylene blue (MB) under UV light irradiation. The result indicates that the performance of photocatalytic activity from all samples increases along with the increasing concentration of atomic dopant.