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"This second edition of Nanocrystalline materials provides updated information on the development and experimental work on the synthesis, properties, and applications of nanocrystalline materials. Nanocrystalline materials with new functionalities show great promise for use in industrial applications, such as reinforcing fillers in novel polymer composites and substantial progress has been made in the past decade in their synthesis and processing. This book focuses primarily on 1D semiconducting oxides and carbon nanotubes, 2D graphene sheets and 0D nanoparticles (metals and inorganic semiconductors). These materials are synthesized under different compositions, shapes and structures, exhibiting different chemical, physical and mechanical properties from their bulk counterparts. This second edition presents new topics relevant to the fast-paced development of nanoscience and nanotechnology, including the synthesis and application of nanomaterials for drug delivery, energy, printed flash memory, and luminescent materials. With contributions from leading experts, this book describes the fundamental theories and concepts that illustrate the complexity of developing novel nanocrystalline materials, and reviews current knowledge in the synthesis, microstructural characterization, physical and mechanical behavior, and application of nanomaterials."

"Material Perovskite-like layered structrure (PLS) La2Ti2O7 merupakan material feroelektrik yang sangat aplikatif dengan didasarkan pada sifat piezoelektrik, piroelektrik, dan elektro optik yang dimilikinya. Feroelektrik dikatakan unggul ketika memiliki sifat dielektrik yang tinggi yang dapat diaplikasikan untuk DRAM (Dynamic Random Access Memory) pada kapasitornya. PLS La2Ti2O7 dengan substitusi Zn2+ di situs Ti (La2Ti2- xZnxO7) dengan x = 0.0, 0.1, 0.2 berhasil disintesis menggunakan metode sol-gel yang dilanjutkan dengan proses sintering. Karakterisasi sampel telah dilakukan untuk mempelajari sifat struktur dengan data hasil XRD, SEM-EDS, UV-Vis dan sifat listrik dengan metode sprektoskopi impedansi. Hasil uji XRD menunjukkan bahwa semua sampel La(Ti,Zn)O single phase dan memiliki struktur stabil monoklinik dengan space group P21. Jari-jari atom doping Zn2+ (0.74 Ǻ) yang lebih besar dari atom Ti4+(0.61 Ǻ) menyebabkan pergeseran sudut 2θ lebih rendah sehingga parameter kisi akan lebih besar dan sebanding dengan volumenya. Hasil uji SEM menunjukkan bahwa penambahan konsentrasi Zn2+ menyebabkan grain size menurun yang konsisten dengan hasil yang diperoleh XRD yang mengkonfirmasi terjadinya penurunan cristalllite size seiring dengan kenaikan konsentrasi doping. Hasil EDX menunjukkan pada sampel murni tidak terdapat Zn di dalamnya dengan nilai persen atomic dan persen berat unsur Ti4+ menurun dan menunjukkan kenaikan pada unsur Zn2+ seiring kenaikan konsentrasi x. Hasil uji UV- Vis dengan data absorbansi diplot menggunakan metode tauc dan menghasilkan nilai energy band gap yang meningkat seiring kenaikan konsentrasi x. Hasil ini dikonfirmasi dengan hasil uji listrik yang menunjukkan nilai konstanta dielektrik yang meningkat dan konduktivitas yang meningkat seiring peningkatan konsentrasi x dikarenakan ada banyak kekosongan oksigen yang berkorelasi dengan hasil SEM.

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Perovskite-like layered structure (PLS) La2Ti2O7 is a highly applicable ferroelectric material based on its piezoelectric, pyroelectric, and electro-optic properties. Ferroelectric is said to be superior when it has high dielectric properties that can be applied to DRAM (Dynamic Random Access Memory) in the capacitor. PLS La2Ti2O7 with Zn2+ substitution at the B-site (La2Ti2-xZnxO7) with x = 0.0, 0.1, 0.2 was successfully synthesized using the sol-gel method followed by a sintering process. Sample characterization was carried out to study the structural properties using XRD, SEM-EDS, UV-Vis, and electrical properties using impedance spectroscopic methods. XRD test results showed that all samples of La(Ti,Zn)O were single phase and had a stable monoclinic structure with space group P21. The atomic radius of Zn2+ doped (0.74 ) which is larger than that of Ti4+ (0.61 ) causes a lower 2θ angular shift so that the lattice parameters (a, b, c) will be larger and proportional to the volume. The SEM test results show that the addition of Zn2+ concentration causes the grain size to decrease which is consistent with the results obtained by XRD which confirms a decrease in crystallite size along with the increase in doping concentration. The EDX results show that in the pure sample there is no Zn in it with the atomic percent and weight percent values of Ti4+ decreasing and showing an increase in Zn2+ as the concentration of x increases. The results of the UV-Vis test with absorbance data plotted using the tauc method and resulted in an energy band gap value that increased with the increase in x concentration. This result was confirmed by the electrical test results which showed an increasing dielectric constant value and an increasing conductivity with an increase in x concentration due to the presence of many oxygen vacancies which correlated with the SEM results."

"Aplikasi serat alam terus berkembang di berbagai sektor industri. Serat kenaf merupakan serat alam yang digunakan dalam penelitian ini karena memiliki sifat mekanik yang cukup tinggi. Busa poliuretan (PU) banyak digunakan sebagai lapisan inti dalam konstruksi komposit sandwich untuk menghasilkan suatu material ringan. Penelitian ini bertujuan menganalisa hasil karakterisasi nanoselulosa dari serat kenaf, menganalisa pengaruh nanoselulosa / Cellulose Nanofiber (CNF) serat kenaf sebagai pengisi (filler) dalam komposit busa PU-CNF, serta merumuskan formulasi komposit busa PU-CNF yang memberikan sifat mekanik terbaik sebagai material kuat dan ringan dalam aplikasi struktural. Nanoselulosa merupakan nanomaterial alami yang dapat diekstrak dari dinding sel tanaman yang memiliki sifat-sifat menarik seperti kekuatan yang tinggi, kekakuan yang sangat baik, dan luas permukaan yang tinggi. Variasi berat CNF yang ditambahkan ke dalam busa PU adalah 0, 3, 5, 7, dan 10 wt%. Proses ekstraksi CNF dari serat kenaf dimulai dengan pre-treatment serat meliputi proses alkalisasi dengan natrium hidroksida dan proses bleaching dengan natrium hipoklorit lalu selanjutnya diberikan perlakuan mekanik dengan alat Ultra Fine Grinder untuk menghasilkan suspensi CNF. Fabrikasi komposit PU-CNF menggunakan metode in-situ polimerization. Karakterisasi CNF meliputi TEM, XRD, dan FT-IR. Hasil TEM pada CNF mengkonfirmasi dimensi berskala nano dari CNF yaitu memiliki diameter pada kisaran 40-70 nm. Hasil FT-IR yang menunjukkan tidak adanya puncak pada daerah panjang gelombang 1700–1740 cm-1 menyatakan pre-treatment pada serat kenaf berhasil mengurangi kandungan non-selulosa. Hasil XRD menunjukkan bahwa kritastalinitas CNF setelah perlakuan mekanik adalah menjadi 75,22%. Karakterisasi komposit busa PU-CNF meliputi uji tekan, uji lengkung-3-titik, dan SEM. Nilai kuat tekan optimal diperoleh pada komposit busa KFCNF3/PU dengan nilai kuat tekan dan modulus tekan optimal masing-masing adalah 284,434 kPa dan 7,32 MPa. Nilai kuat lengkung-3-titik optimal juga diperoleh pada komposit busa PU berpenguat 3wt% CNF yaitu 734,145 kPa. Komposit busa PU berpenguat 3 wt% CNF merupakan komposit terbaik yang memiliki nilai optimum dari hasil uji tekan dan uji lengkung-3-titik.

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Natural fiber applications continue to grow in various industrial sectors. Kenaf fiber is a natural fiber that was used in this study because it has high mechanical properties. Polyurethane (PU) foam is widely used as a core layer in sandwich composite construction to produce a lightweight material. The objective of this research was to analyze the results of nanocellulose characterization from kenaf fibers, to analyze the effect of nanocellulose / Cellulose Nanofiber (CNF) kenaf fiber as a filler in PU-CNF foam composites, and to formulate a PU-CNF foam composite formulation that provided the best mechanical properties as strong and lightweight materials in structural applications. Nanocellulose is a natural nanomaterial that can be extracted from plant cell walls which has attractive properties such as high strength, excellent stiffness and high surface area. The CNF weight variations in PU foam were 0, 3, 5, 7, and 10 wt%. The CNF extraction process from kenaf fiber started with fiber pre-treatment including alkalization with sodium hydroxide and bleaching with sodium hypochlorite and then mechanical treatment with an Ultra Fine Grinder to produce CNF suspension. PU-CNF composites were fabricated using in-situ polymerization method. CNF characterization included TEM, XRD, and FT-IR. TEM results on CNF confirmed that the CNF diameter was in the range of 40-70 nm. FT-IR results showed that no peaks in the 1700-1740 cm-1 wavelength region and this confirmed that pre-treatment on kenaf fibers succeeded in reducing the non-cellulose content. XRD results showed that the crystallinity of CNF after mechanical treatment was 75.22%. The PU-CNF foam composite characterization included compressive test, 3-point bending test, and SEM. The optimal compressive strength values obtained in the PU foam reinforced 3 wt% CNF composites with the optimal compressive strength and modulus values were 284,434 kPa and 7,32 MPa, respectively. The optimal 3-point bending strength value was also obtained in the PU foam reinforced 3 wt% CNF composites, which was 734.145 kPa. PU foam reinforced 3 wt% CNF composites were the best composites that have the optimum value from the results of the compressive and 3-point-bending tests."

"This book gives an overview of nanostructures and nanomaterials applied in the fields of energy and organic electronics. It combines the knowledge from advanced deposition and processing methods of nanomaterials such as laser-based growth and nanopatterning and state-of-the-art characterization techniques with special emphasis on the optical, electrical, morphological, surface and mechanical properties. Furthermore it contains theoretical and experimental aspects for different types of nanomaterials such as nanoparticles, nanotubes and thin films for organic electronics applications. "

"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."

"This volume is concerned with functional nanomaterials: materials containing specific, predictable nanostructure whose chemical composition or interfacial structure enable them to perform a specific job? destroy, sequester or detect some material that constitutes an environmental threat. Nanomaterials have a number of features that make them ideally suited for this job: high surface area, high reactivity, easy dispersability, and rapid diffusion. The purpose of this book is to showcase how these features can be tailored to address some of the environmental remediation and sensing/detection pr."

"Materials science and engineering of carbon : fundamentals provides a comprehensive introduction to carbon, the fourth most abundant element in the universe. The contents are organized into two main parts. Following a brief introduction on the history of carbon materials, Part 1 focuses on the fundamental science on the preparation and characterization of various carbon materials, and Part 2 concentrates on their engineering and applications, including hot areas like energy storage and environmental remediation. The book also includes up-to-date advanced information on such newer carbon-based materials as carbon nanotubes and nanofibers, fullerenes and graphenes."