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"Nanocomposite thin films consisting of titanium oxide, or TiO2, nanoparticles embedded in apolymer matrix represent a new class of potential materials for optoelectronic applications such as optical switches, waveguides, high refractive indices and non-linear optical devices. Among the various processing techniques under development for these nanocomposites, the in situ sol−gel process is known to be versatile as it enables control of the inorganic-organic interaction at various molecular, nanometer, and micrometer scales. However, the sol−gel process has a major limitation, which is the low crystallinity in the resulting TiO2 phase due to relatively low processing temperatures. Therefore, the current research is aimed at investigating the nanostructural evolution of theTiO2 crystallite during the in situ sol−gel process to gain a better understanding of the mechanisms responsible for the largely amorphous nature of TiO2 nanoparticles. For this purpose, two sol−gel parameters, i.e., the hydrolysis ratio (Rw) and pH value of the TiO2 precursor solution were varied. On the basis of XRD and FTIR analyses, it was found that the largely amorphous TiO2 state is related to the fast development of stiff Ti−OH networks during the hydrolysis and condensation stag es of the sol−gel process, and concurrently worsened by the formation of the rigid PMMA matrix upon thermal annealing."

"Nanopartikel hybrid oksida besi/oksida tembaga/oksida seng telah disintesis dengan menggunakan metode sol-gel untuk tiga variasi molar. Seluruh sampel dikarakterisasi dengan spektroskopi X-Ray Diffraction, Field Emission Scanning Electron Microscopy, Vibrating Sample Magnetometer, Energy Dispersive X-Ray, Ultraviolet-visible Reflectance dan Fourier-Transform Infrared. Nanopartikel hybrid yang dihasilkan menunjukkan karakteristik feromagnetik dengan morfologi yang merupakan gabungan spherical-like dari oksida besi dan oksida seng dan clews-like dari oksida tembaga. Keempat unsur penyusunan nanopartikel hybrid hadir dalam bentuk ikatan Zn-O, Fe-O dan Cu-O dengan kehadiran fase dan struktur tunggal dari inverse cubic spinel magnetite, hexagonal wurtzite oksida seng dan monoclinic oksida tembaga. Celah energi nanopartikel hybrid cenderung turun dengan berkurangnya rasio molar oksida seng yang berhubungan dengan peningkatan kuantitas oksida besi dan oksida tembaga. Kondisi optimum aktivitas fotokatalitik nanopartikel hybrid dalam mendegradasi methylene blue dengan pemaparan cahaya ultraviolet diperoleh pada kondisi basa untuk pH 13. Nanopartikel hybrid dengan rasio molar 1:1:5 mampu menghasilkan degradasi maksimum dengan laju degradasi yang lebih tinggi dibandingkan nanopartikel oksida seng. Hole ditemukan sebagai spesies yang berperan aktif dalam aktivitas fotokatalitik nanopartikel hybrid dalam mendegradasi methylene blue.Iron oxide/cuprix oxide/zinc oxide hybrid nanoparticles with three variation of molar ratio have been synthesized using sol-gel methods. All samples were characterized by X-Ray Diffraction, Field Emission Scanning Electron Microscopy, Vibrating Sample Magnetometer, Energy Dispersive X-Ray, Ultraviolet-visible Reflectance and Fourier-Transform Infrared Spectroscopies. The resulting hybrid nanoparticles show ferromagnetic behaviour and have combination of spherical-like of iron oxide and zinc oxide morphologies with clews-like of cuprix oxide morphology. The four elements of the hybrid nanoparticles present in the form of Zn-O, Fe-O and Cu-O bonds and form individual crystal structures and phases of cubic inverse spinel of iron oxide, hexagonal wurtziteof zinc oxide and monoclinic of cuprix oxide. Energy gap of the hybrid nanoparticles tend to shift to lower energy that associates with increasing quantity of iron oxide and cuprix oxide with decreasing zinc oxide molar ratio. Optimum condition for photocatalytic activity of the hybrid nanoparticles in degrading methylene blue under ultraviolet light irradiation is obtained under alkaline conditions for pH 13. Hybrid nanoparticles with a molar ratio of 1:1:5 is able to produce the maximum degradation with higher degradation rate than zinc oxide nanoparticles. Hole found as species that plays an active role in photocatalytic activity of the hybrid nanoparticles to degrade methylene blue."

"Concerns about global warming and the depletion of oil reserves have led to significant research into more sustainable composite materials made from natural materials. Recently, research has focussed on the development of nanoscale reinforcements for this new group of composites, significantly improving and extending their range of desirable properties. Environmentally friendly polymer nanocomposites summarises this wealth of research and its practical implications.After an introduction to the subject, part one looks at matrix and reinforcement materials as well as their characterisation. Part two reviews key properties such as tensile and dynamic mechanical properties and thermal stability. It also considers issues such as barrier properties, biodegradability, rheology, electrical and thermal conductivity. The book concludes by reviewing potential applications."

"Aplikasi praktis dari solusi nanopartikel telah dibatasi karena memiliki dampak yang buruk pada degradasi mekanik. Tujuan penelitian ini adalah untuk menguji karakteristik aliran nanofluida. Hasil percobaan berupa kurva aliran dari nanofluida pada sebuah pipa kapiler yang mempunyai variabel tekanan. Yang diameter pipa tersebut adalah sebesar 3 mm. Tegangan geser dan regangan geser dihitung dengan mengukur pressure drop dan laju aliran volumetrik. Pengukuran pressure drop dilakukan untuk Al2O3 dan TiO2 (konsentrasi 1%, 3% dan 5%) dengan menggunakan pressure tranducer. Power Law Index berada pada kisaran harga 0,95 ~ 1,0. Koefisien gesekan nanofluida yang telah didapat, dibandingkan dengan data dari air murni yang digambarkan dengan persamaan Blasius.

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The practical application of the nanoparticle of solutions has been limited because it has an adverse effect on mechanical degradation. The aim of this study is to examine characteristics of flow properties of nanofluid. Experiments are carried out the measurement of the flow curve of the nanofluid by a capillary pipe applying variable pressure driven flow. It is 3 mm in the diameter of the capillary. The shear stress and the shear strain are calculated by measuring the pressure drop and the volumetric flow rate, respectively. Measurements of pressure drop are carried out for Al2O3 and TiO2 at 1%, 3%, 5% particle volume with pure water by a pressure transducer. The power law exponent are about 0.95 ! 1.0. The friction coefficient of nanofluid in a capillary pipe are fit with pure water data as Blasius's equation."

"Nanotubes mendapat perhatian yang sangat besar karena memiliki rasio luas permukaan yang tinggi, hal ini penting dalam aplikasinya sebagai elektroda Dye Sensitized Solar Cell (DSSC). Pada penelitian ini telah difabrikasi nanotubes TiO2 melalui teknik hidrotermal standar dimana serbuk nano TiO2 P25 Degussa dilarutkan pada larutan alkalin sodium hidroksida berkonsentrasi tinggi di dalam otoklaf tersegel. Untuk meningkatkan nanokristalinitas, dilakukan sebuah modifikasi dimana proses anil konvensional dikombinasikan dengan pasca hidrotermal. Detail struktur, morfologi dan kristalinitas diuji dengan XRD, spektroskopi Raman, SEM dan TEM, sedangkan sifat optik dari nanotubes diinvestigasi dengan spektroskopi UV-Vis.Hasil investigasi menunjukkan bahwa dengan memberikan kombinasi anil konvensional dan pasca hidrotermal pada nanotubes, nanokristalinitas dapat ditingkatkan secara signifikan pada saat yang sama integritas struktur hollow tetap terjaga. Untuk sampel nanotube yang sebelumnya diberikan anil 150°C, ukuran kristalit anatase bertambah dari 6,93 sampai 7,82 nm setelah perlakuan pasca hidrotermal 80-150°C. Peningkatan nanokristalinitas lebih besar ditunjukkan ketika temperatur anil dinaikkan sampai 300°C kemudian dilanjutkan pasca hidrotermal yang sama, menghasilkan peningkatatan ukuran kristalit mulai dari 17,20 sampai 18,30 nm. Energi celah pita yang dihasilkan nanotubes berbanding terbalik dengan ukurun kristalit, dimana nilai terendah sebesar 3,19 eV didapatkan dari ukuran kristalit terbesar yaitu 18,30 nm. Nanotubes ini juga memberikan sirkuit tegangan terbuka pada DSSC hasil fabrikasi sebesar 108 mV.

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TiO2 nanotubes have attracted extensive attention because it has a high surface area to volume ratio, which is important for its application as electrodes in dye sensitized solar cells (DSSC). In this study, TiO2 nanotubes have been fabricated through a standard hydrothermal technique where TiO2 P25 Degussa nanopowder was dissolved in highly concentrated alkaline solution of sodium hydroxide (NaOH) in a sealed autoclave. For nanocrystallinity improvement, a modification route was carried out where the conventional annealing process was combined with post-hdyrothermal treatment. The detail of the structure, morphology and crystallinity of the resulting nanotubes were examined by XRD, Raman spectroscopy, SEM and TEM, while the optical properties of nanotubes was investigated by UV-visible spectroscopy.

The result of investigation showed that by subjecting the nanotubes to the combined treatment of annealing and post-hydrothermal, the nanocrystallinity of nanotubes can be enhanced significantly while the integrity of the hollow structure can be well-maintained. For the nanotube sample which has been previously annealed at 150°C, the crystallite size of anatase TiO2 in nanotubes increased from 6.93 to 7.82 nm after being subjected to post-hydrothermal treatment at 80 to 150°C. Further improvement in nanocrystallinity was obtained when the temperature of annealing process was raised up to 300°C prior to the same post-hydrothermal procedure, resulting in nanocrystallite size enhancement from 17.20 to 18.30 nm. The band gap energy of the resulting nanotubes is inversely proportional to the crystallite size of anatase phase where the lowest value of 3.19 eV was obtained from the nanotube sample with a biggest crystallite size of 18.30 nm. This nanotube also provided the highest open circuit votage in the fabricated DSSC of 108 mV."

"This thesis addresses the fabrication and investigation of the optical response of gold nanoparticle arrays supported on insulating LiF(110) nanopatterned substrates. Motivated by the discovery of the intriguing effects that arise when electromagnetic radiation interacts with metallic nanostructures, the thesis focuses on the application of bottom-up approaches to the fabrication of extended-area plasmonic nanostructures, and the optimization of their optical response. By developing a sophisticated effective-medium model and comparing the experimental findings with model calculations, the author explores the role of the interparticle electromagnetic coupling and array dimensionality on the collective plasmonic behavior of the array, giving insights into the physical mechanisms governing the optical response."

"Health and environmental safety of nanomaterials addresses concerns about the impact of nanomaterials on the environment and human health, and examines the safety of specific nanomaterials. Understanding the unique chemical and physical properties of nanostructures has led to many developments in the applications of nanocomposite materials. While these materials have applications in a huge range of areas, their potential for toxicity must be thoroughly understood.Part one introduces the properties of nanomaterials, nanofillers, and nanocomposites, and questions whether they are more toxic than their bulk counterparts. Part two looks at the release and exposure of nanomaterials. The text covers sampling techniques and data analysis methods used to assess nanoparticle exposure, as well as protocols for testing the safety of polymer nanocomposites. It explains characterization techniques of airborne nanoparticles and life cycle assessment of engineered nanomaterials. Part three focuses on the safety of certain nanomaterials, including nanolayered silicates, carbon nanotubes, and metal oxides. In particular, it explores the potential ecotoxicological hazards associated with the different structures of carbon nanotubes and the safe recycling of inorganic and carbon nanoparticles. The final two chapters address the risks of nanomaterials in fire conditions, their thermal degradation, flammability, and toxicity in different fire scenarios."

"Tribology of polymeric nanocomposites provides a comprehensive description of polymeric nanocomposites, both as bulk materials and as thin surface coatings, and provides rare, focused coverage of their tribological behavior and potential use in tribological applications.Providing engineers and designers with the preparation techniques, friction and wear mechanisms, property information and evaluation methodology needed to select the right polymeric nanocomposites for the job, this unique book also includes valuable real-world examples of polymeric nanocomposites in action in tribological applications."

"Metilen biru merupakan salah satu limbah industri yang berbahaya bagi lingkungan dan tidak terdegradasi secara alami. Pada penelitian ini digunakan green synthesis Au/ZnO menggunakan daun Ocimum americanum untuk mendegradasi metilen biru. Ekstrak daun kemangi berperan sebagai pereduksi dan penstabil dalam proses modifikasi Au pada permukaan ZnO. AuNP optimum terbentuk pada cahaya ruang dengan konsentrasi EDK 0.1% (w/v). Karakterisasi dengan spektrofotometer UV-Vis dan Particle Size Analyzer (PSA) menunjukkan AuNP mempunyai panjang gelombang maksimum (max) 531nm dengan ukuran 2.875 nm. Karakterisasi XRD dan TEM-SAED menunjukkan AuNP memiliki kristalin fcc dan memiliki diameter dengan ukuran rata-rata 20nm dengan bentuk spheric (bulat). Au/ZnO dikarakterisasi menggunakan spektrofotometer UV-Vis DRS untuk mengetahui nilai band gap. Karakterisasi UV-Vis DRS menunjukkan adanya absorbsi pada panjang gelombang 525 nm yang menghasilkan nilai band gap sebesar 3.09 eV setelah dilakukan perhitungan. Hasil karakterisasi XRD dan TEM-SAED menunjukkan bahwa terdapat AuNP pada permukaan ZnO. Fotodegradasi metilen biru diamati menggunakan radiasi lampu natrium selama 60 menit yang selanjutnya dikarakterisasi menggunakan spektrofotometer UV-Vis. Persentase degradasi dari ZnO dan Au/ZnO terhadap metilen biru adalah 16.13% dan 82.50%. Dalam studi kinetika reaksi didapatkan bahwa tetapan laju degradasi untuk Au/ZnO mengikuti kinetika orde 1.

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Methylene blue is one of hazardous industrial waste for the environment and non biodegradable. In this research, modification AuNP on ZnO were prepared by green synthesis using leaf extract Ocimum americanum for photodegradation methylene blue. Extract of Ocimum americanum was acts as reducing agents and stabilizer in modification of AuNPs on ZnO. The optimum condition of AuNPs was synthesized using visible light with the concentration of EDK 0.1% (w/v). Characterization of UV-Vis spectrophotometer and Particle Size Analyzer (PSA) shows AuNP has maximum wavelength (max) 531 nm with size 2.875 nm. Characterization of XRD and TEM-SAED shows AuNP has fcc crystaline and range diameter of AuNP 20nm with spheric shape. Au/ZnO were characterized using spectrophotometer UV-Vis DRS to examined the band gap value. Characterization of UV-Vis DRS shows absorption at wavelength 525 nm and then the band gap value was calculated to be 3.09 eV. The characterization results of XRD and TEM-SAED indicate the presence of AuNP on ZnO surface. Photodegradation of methylene blue was observed using radiation of natrium lamp through 60 minutes and then characterized using UV-Vis spectrophotometer. Degradation percentage of ZnO and Au/ZnO towards methylene blue is 16.13% and 82.50%. In study of reaction kinetics shows that degradation for Au/ZnO followed the first order kinetics."

"Pada penelitian ini telah dilakukan sintesis nanostruktur TiO2 melalui proses sol- gel dengan variasi pengaruh surfaktan, metodologi, waktu kalsinasi dan suhu kalsinasi dari larutan TiOSO4 hasil ekstraksi Ilmenit (FeTiO3) yang merupakan produk sampingan dari proses mineral dressing bijih timah (cassiterit) di pulau Bangka. Karakterisasi XRD dilakukan untuk mengukur besar ukuran kristalit nanostruktur TiO2 yang dihasilkan. Dari hasil perhitungan besar ukuran kristalit diperoleh hasil Sampel P-25 Degussa memiliki ukuran Kristalit 21,08 nm diikuti dengan sampel penambahan surfaktan F127+TEOS 12 nm, penambahan surfaktan Dextrin 9,45 nm, tanpa penambahan surfaktan 5,71 nm, penambahan surfaktan F127 4,95 nm. Setelah itu dilakukan karakterisasi UV-Vis untuk mengetahui Energi Celah pita untuk memastikan nanostruktur TiO2 tersebut merupakan material semikonduktor, hasil yand diperoleh dari perhitungan yang mempunyai energi celah pita tertinggi adalah sampel TEOS 3,8 eV, diikuti oleh sampel Dextrin 3,28 eV, sampel F127 3,2 eV, sampel P-25 Degussa 3,19 dan sampel tanpa surfaktan 3,19 selanjutnya karakterisasi menggunakan PSA untuk mengetahui ukuran dan distribusi partikel sampel dengan ukuran partikel terbesar adalah sampel sampel F127+TEOS yakni 1840 nm diikuti sampel tanpa penambahan surfaktan 858,3 nm, sampel F127 530nm, dan sampel Dextrin 92,8nm. Dan detil struktur dan morfologi diperoleh dari hasil karakterisasi SEM, diperoleh struktur spheroida pada sampel Dextrin dan berukuran nano.

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In this study has been conducted through the synthesis of nanostructured TiO2 sol-gel process with surfactant variation influences, methodology, calcination time and calcination temperature of the extraction solution TiOSO4 ilmenite (FeTiO3) which is a by product of the process mineral ore dressing (cassiterit) on the Bangka Island . XRD characterization performed to measure the size of the resulting TiO2 nanostructured crystallites. From the calculation of the crystallite size of the obtained results Sample P-25 Degussa has Crystallite size of 21.08 nm followed by sample the addition of surfactant F127 + TEOS 12 nm, the addition of surfactant dextrin 9.45 nm, without the addition of surfactant 5,71 nm, the addition of surfactant F127 4.95 nm. After that UV-Vis characterization to determine the energy band gap to ensure nanostructured TiO2 is a semiconductor material, were associated with the results obtained from the calculations that have the highest energy band gap of 3.8 eV is a sample of TEOS, followed by dextrin samples 3.28 eV, sample F127 3.2 eV, sample P-25 Degussa 3.19 and samples without surfactant. further characterization using PSA to determine particle size and distribution of the sample with the largest particle size of a sample is a sample F127 + TEOS followed the 1840 nm sample without the addition of surfactant 858.3 nm, 530nm F127 samples, and samples dextrin 92.8 nm. And the detailed structure and morphology obtained from SEM characterization results, obtained on samples dextrin spheroida structures and nano-sized."