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"In this thesis, Claudia Backes guides the reader through her multidisciplinary research into the non-covalent functionalization of carbon nanotubes in water. Although one of the most remarkable materials of the 21st century, carbon nanotubes often have limited application because of their intrinsically low solubility and polydispersity. The author shows that rational surfactant design is a powerful tool for chemists because it can unmask the key to solubilization and allow us to tailor nanotube surface and optical properties in a fully reversible fashion. Aspects of organic, physical and analytical chemistry, as well as colloidal sciences are covered in this outstanding work which brings us one step closer to exploiting this super-material to its full potential."

"Chapters review analysis and remediation of pollutants such as greenhouse gases, chiral pharmaceuticals, dyes, chlorinated organics, arsenic, toxic metals and pathogen in air, water, plant and soil. Several highlights include the overlooked impact of air pollutants from buildings for health risk, innovative remediation techniques such as bioreactors for gas treatment, electrochemical cleaning of pharmaceuticals, sequestration on Fe-Mn nodules, phytoremediation and photocatalytical inactivation of microbial pathogens."

"David I.A. Millar's thesis explores the effects of extreme conditions on energetic materials. His study identifies and structurally characterises new polymorphs obtained at high pressures and/or temperatures. The performance of energetic materials (pyrotechnics, propellants and explosives) can depend on a number of factors including sensitivity to detonation, detonation velocity, and chemical and thermal stability. Polymorphism and solid-state phase transitions may therefore have significant consequences for the performance and safety of energetic materials. In order to model the behaviour of these important materials effectively under operational conditions it is essential to obtain detailed structural information at a range of temperatures and pressures."

"This compendium focuses on what the research community labels as solid state gas sensors, where a gas directly changes the electrical properties of a solid, serving as the primary signal for the transducer. It starts with a visionary approach to how life in future buildings can benefit from the power of gas sensors. The requirements for various applications. Further contributions highlight current trends in new sensing principles, such as the use of nanomaterials and how to use new sensing principles for innovative applications in e.g. meteorology. "

"Material semikonduktor TiO2 yang digunakan sebagai fotoelektroda hanya dapat diaktifkan pada daerah sinar UV karena memiliki energi band gap yang relative besar. Untuk memperbaiki respon cahaya fotoelektroda, dilakukan pengembangan metode yang dapat mengubah respon fotokatalisis dari sinar UV ke sinar visible dengan menambahkan dopan karbon pada TiO2 nanotube. Menarik pula untuk diinvestigasi apabila sebelum dilakukan proses doping karbon, matriks TiO2 nanotube diperkaya terlebih dahulu dengan spesi Ti3+. Adanya spesi Ti3+ dapat memberikan hasil lebih baik daripada hanya menambahkan dopan karbon pada TiO2 nanotube. Spesi Ti3+ yang terdapat di dalam C-TiO2 nanotube diharapkan dapat memperkecil nilai energi band gap sehingga respon serapan sinar tampak lebih baik, arus cahaya yang dihasilkan lebih besar, dan meningkatkan kinerja fotoanoda dalam menghasilkan gas H2. Berdasarkan karakterisasi SEM, diameter tabung TiO2 nanotube yang dihasilkan rata-rata sebesar 68,92 nm. Dari karakterisasi XRD, didapatkan TiO2 nanotube yang berfasa anatase. Dari persamaan Kubelka-Munk, diperoleh nilai energi celah pita TiO2 nanotube sebesar 3,18 eV. Dari hasil MPA, arus cahaya TiO2 nanotube yang dihasilkan sinar UV (0,000011 mA/cm2) lebih tinggi daripada sinar visible (0,000007 mA/cm2). Hal ini menunjukkan bahwa TiO2 nanotube memiliki aktivitas fotokatalitik pada daerah sinar UV.

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Material of TiO2 semiconductor as a photoelectrode can only be activated in the UV light region because it has a relatively large band gap energy. To improve the photoelectrode, an effort was developed to shift the photocatalytic response visible light by adding carbon dopant in to TiO2 nanotube. It is also interesting to investigate if before the carbon doping process is carried out, the TiO2 nanotube matrix is enriched first with the Ti3+ species. The presence of Ti3+ species can give better results than just adding carbon dopant to TiO2 nanotube. Ti3+ species contained in C-TiO2 nanotube are expected to reduce the band gap energy value better response in visible light absorption, resulting higher photocurrent, and improve the performance of photoanode in producing H2 gas. Based on SEM characterization, tube diameter of TiO2 nanotube on average is 68,92 nm. From XRD characterization, obtained TiO2 nanotube which has an anatase phase. From Kubelka-Munk equation, band gap energy of TiO2 nanotube is 3,18 eV. From MPA result, photocurrent of TiO2 nanotube produced by UV light (0.000011 mA/cm2) is higher than visible light (0.000007 mA/cm2). This shows that TiO2 nanotube has photocatalytic activity in the UV light region."

"Carbon Nanotube (CNT) merupakan material multifungsi yang akan dibutuhkan dalam jumlah besar di masa depan. Terdapat metode yang sangat menjanjikan untuk memproduksi CNT dalam jumlah besar yaitu dengan Chemical Vapor Deposition (CVD) dalam reaktor unggun terfluidisasi. Oleh karena itu, penelitian ini difokuskan untuk dapat menghasilkan model reaktor unggun terfluidsasi sehingga dapat dikembangkan menjadi reaktor skala pabrik yang mampu memproduksi CNT dalam skala besar secara efisien. Persamaan peristiwa perpindahan untuk fenomena fisik yang berlangsung dalam reaktor akan dikombinasikan dengan persamaan kinetika reaksi dengan menggunakan Computational Fluid Dynamics (CFD) dalam COMSOL Multiphysics sehingga dihasilkan sebuah model reaktor. Selanjutnya model akan disimulasikan dengan variasi parameter proses. Hasil simulasi menunjukkan bahwa profil konsentrasi metana dipengaruhi oleh suhu dinding reaktor, rasio umpan, laju alir gas, tekanan umpan, dan ukuran katalis. Konversi metana dan yield karbon meningkat seiring dengan peningkatan suhu dinding reaktor, kandungan hidrogen dalam umpan, dan kecepatan fluida di dalam reaktor. Sedangkan konversi metana menurun seiring meningkatnya tekanan umpan dan ukuran katalis. Konversi metana pada model reaktor unggun terfluidisasi yang disimulasikan adalah sebesar 77% dengan Yield CNT yang dihasilkan sebesar 0.66 gCNT/gCat dalam waktu reaksi selama 5 jam.

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Carbon Nanotube (CNT) is well known material having an unique properties and will become future materials. Promising way to synthesize a large scale of CNT is through the Chemical Vapor Deposition in fluidized bed reactor. Focus of this research is to get fluidized bed reactor model which representate the condition and performance in the real reactor. Method of this research is develop model of mathematic equation based on mass, momentum, and energy balance. COMSOL Multiphysics is used to develop the model and for running simulation for several process parameter such as temperature, pressure, etc.

The simulation results show that the methane concentration profile is influenced by the temperature of the walls of the reactor, the feed ratio, gas flow rate, feed presure, and radius of catalyst particles. Conversion of methane and carbon yield increases with increasing temperature of the reactor wall, the addition hydrogen in reactant and the velocity of the fluid in the reactor. Conversion of methane decreases with increasing of feed pressure and radius of catalyst particles. In this model, conversion of methane was about 77% and Yield of CNT was about 0.66 gCNT/gCat for 5 hours of reaction."

"ABSTRAKProduksi nanotube karbon jenis Single Walled Nanotube Carbon (SWNT) danFew Walled Nanotube Carbon (FWNT) masih sulit untuk dilakukan. Salah satupenyebab utama adalah pemilihan katalis yang kurang tepat. Penelitian inimenggunakan katalis Fe/Mo/MgO untuk menghasilkan SWNT atau FWNT(diameter luar nanotube karbon kurang dari 10 nm). Katalis Fe/Mo/MgOdipreparasi dengan metode sol gel/spray coating. Nanokarbon akan dihasilkanmelalui reaksi dekomposisi katalitik metana pada suhu 850oC dengan katalisFe/Mo/MgO. Hasil penelitian menunjukkan konversi metana tertinggi mencapai97,64% dan yield karbon sebesar 1,48 gc/gkat. Nanokarbon kemudiandikarakterisasi dengan Transmission Electron Microscope (TEM). Nanokarbonyang dihasilkan pada penelitian ini terdiri atas nanotube karbon jenis FWNT(range diameter luar 4,5 nm ? 10 nm). Selain itu, MWNT (Multi Walled NanotubeCarbon, range diameter luar 10 nm ? 89,5 nm), carbon nanofiber, coil nanotube,dan bamboo-shaped carbon juga telah dihasilkan. Jenis nanokarbon yangdihasilkan bukan hanya jenis nanotube karbon disebabkan oleh waktu reaksi yangterlalu panjang serta diameter partikel katalis 20 nm hingga 100 nm yangterdeteksi dari hasil X-Ray Diffraction (XRD) dan Field Emmision ScanningElectron Microscope (FE SEM). Untuk memperbaiki hasil ini, running padapenelitian ini dilakukan sekali lagi dengan waktu reaksi 30 menit dengan waktureduksi 30 menit di suhu 850oC dan suhu kalsinasi 550oC di udara. Hasilnanokarbon yang diperoleh memiliki range diameter luar yang lebih kecil danberkisar antara 8,5 nm hingga 66,85 nm yang terukur pada FE SEM. Namun, jenisnanokarbon belum diketahui berupa FWNT atau MWNT atau nanokarbonlainnya.

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AbstractProduction of Single Walled Nanotubes Carbon (SWNT) dan Few WalledNanotubes Carbon (FWNT) is really hard to do recently. It occured due toinappropriate catalyst selection. Fe/Mo/MgO catalyst, used in literature, was usedto make nanotubes carbon. Fe/Mo/MgO catalyst was prepared by sol gel/spraycoating method and it would be reacted with methane in 850oC (methanedecomposition catalytic reaction). The research result shows that the highestmethane conversion reached 97,64% and carbon yield is 1,48 gc/gkat.Transmission Electron Microscope (TEM) indicated that the synthesized productwas FWNT (carbon nanotubes with outer diameter between 4,5 nm ? 10 nm),MWNT (Multi Walled Nanotubes Carbon, outer diameter between 10 nm ? 89,5nm), coil nanotube, carbon nanofiber, dan bamboo-shaped carbon. It is happeneddue to longer time reaction and catalyst diameters have range between 20 nm ?100 nm which detected by XRD and SEM characterization. Then, methanedecomposition catalytic reaction to get nanotube carbon was done once again inshorter times (30 minutes), longer time of reduction (40 minutes), and lowercalcination temperature (550oC) in air. FE SEM indicated that range of outerdiameter nanocarbon between 8,5 nm ? 66,85 nm but its types can not bedetermined by FE SEM."