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"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."

"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."

"The increased use of polymer matrix composites in structural applications has led to the growing need for a very high level of quality control and testing of products to ensure and monitor performance over time. Non-destructive evaluation (NDE) of polymer matrix composites explores a range of NDE techniques and the use of these techniques in a variety of application areas.Part one provides an overview of a range of NDE and NDT techniques including eddy current testing, shearography, ultrasonics, acoustic emission, and dielectrics. Part two highlights the use of NDE techniques for adhesively bonded applications. Part three focuses on NDE techniques for aerospace applications including the evaluation of aerospace composites for impact damage and flaw characterisation. Finally, the use of traditional and emerging NDE techniques in civil and marine applications is explored in part four.With its distinguished editor and international team of expert contributors, Non-destructive evaluation (NDE) of polymer matrix composites is a technical resource for researchers and engineers using polymer matrix composites, professionals requiring an understanding of non-destructive evaluation techniques, and academics interested in this field."

"This book presents a comprehensive knowledge-set of matrix, fiber and interphase behavior under long-term aging conditions, theoretical modeling and experimental methods. This book covers long-term constituent behavior, predictive methodologies, experimental validation and design practice. Readers will also find a discussion of various applications, including aging air craft structures, aging civil infrastructure, in addition to engines and high temperature applications."

"ABSTRAKPenelitian bertujuan untuk mengetahui pengaruh sistem pemolesan terhadap perubahan warna Nano-ionomer. Nano-ionomer dibagi menjadi empat kelompok; dipoles dengan Sof-LexTM XT, PoGOTM, OptraPol®, dan tidak dipoles. Seluruh spesimen direndam dalam larutan kopi selama tujuh hari. Perubahan warna dinilai dengan sistem CIELAB. Hasil dianalisis dengan uji One Way Anova dan PairedSamples T Test. Nilai L* mengalami penurunan yang signifikan (p < 0,05) setelah dilakukan pemolesan. OptraPol® mengalami perubahan warna terkecil. Setelah perendaman, terjadi perubahan nilai L*, a*, dan b* yang signifikan (p < 0,05) pada seluruh kelompok. OptraPol® mengalami perubahan warna terkecil namun tidak berbeda bermakna terhadap PoGOTM dan tidak dipoles.

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ABSTRACTThe aim of this study was to assess the influence of polishing systems on color change of Nano-ionomer. Specimens were divided into four groups; polished with Sof-LexTM XT, PoGOTM, OptraPol® and unpolished. Color values were evaluated using CIELAB system. Data were analyzed using One Way Anova and Paired Samples T Test. L* values were significantly lowered (p < 0,05) after polishing procedures. OptraPol® showed the least colour change. After immersion, therewere significant changes in L*, a* and b* values (p < 0,05) in all groups.OptraPol® showed the littlest colour change but it was not statistically significant compared to PoGOTM and unpolished."

"Komposit hijau merupakan komposit yang salah satu bahan penyusunnya terdiri dari bahan ramah lingkungan. Salah satunya menggunakan serat alam sebagai penguat. Salah satu jenis serat alam yang sering digunakan adalah kenaf. Penelitian ini bertujuan untuk mendapatkan pemodelan sifat elastis komposit berpenguat serat kenaf Sumberejo dengan berbagai variasi matriks polimer. Variasi matriks polimer yang digunakan adalah polipropilena, poli asam laktat, epoksi dan poliester. Pemodelan komposit ini menggunakan teori Rule of mixture dan teori lamina yaitu specially orthotropic. Hasil penelitian menunjukkan bahwa komposit epoksi/ serat kenaf Sumberejo memiliki regangan yang lebih rendah dibandingkan dengan tiga matriks polimer lainnya yaitu sebesar 0,61% untuk longitudinal dan 0,90% untuk transversal. Namun, komposit epoksi/ serat kenaf Sumberejo memiliki modulus elastisitas yang lebih tinggi dibandingkan dengan tiga matriks polimer lainnya yaitu sebesar 9174 MPa untuk longitudinal dan 6639 MPa untuk transversal. Pemodelan sifat elastis komposit pada penelitian ini menunjukkan bahwa komposit epoksi/ serat kenaf Sumberejo memliki sifat mekanik terbaik dibandingkan komposit berpenguat serat kenaf dengan matriks tiga polimer lainnya.

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Green composite is a composite of which one of the constituent materials consists of environmentally friendly materials. One of them uses natural fiber as a reinforcement. One type of natural fiber that is often used is kenaf. This study aimed to obtain an elastic property model of Sumberejo kenaf fiber reinforced composites with a variety of polymer matrix variations. Polymer matrix variations used were polypropylene, polylactic acid, epoxy, and polyester. Rule of mixture and specially orthotropic lamina theories were applied to these composite models. The results of the study indicated that the epoxy/ Sumberejo kenaf fiber composite had lower strain compared to other three polymer matrices with the result of 0,61% for the longitudinal and 0,90% for the transverse. However, the epoxy/ Sumberejo kenaf fiber composite had higher elasticity modulus compared to the other three polymer matrices with the result of 9174 MPa and 6639 MPa for longitudinal and transverse directions respectively. The elastic property modeling from this study indicated that epoxy reinforced Sumberejo kenaf fiber composites had the best mechanical properties compared to the other three polymers reinforced Sumberejo kenaf fiber composites."

"ABSTRAKSenyawa turunan piridin merupakan senyawa yang cukup penting karena memiliki aplikasi dibidang bioaktivitas dan farmasi. Senyawa turunan piridin dapat disintesis dengan metode Hantzsch. Sintesis dilakukan dengan mereaksikan aldehid, etil asetoasetat, dan amonium asetat dengan bantuan nanopartikel CuI sebagai katalis. Pada penelitian ini dilakukan sintesis dua senyawa turunan piridin yang dilakukan dengan memvariasikan aldehid yang digunakan benzaldehid senyawa 1, sinamaldehid senyawa 2. Kondisi optimum yang didapatkan untuk sintesis senyawa ini yaitu dengan menggunakan pelarut etanol, menggunakan jumlah katalis 10 mol, dan dengan waktu reaksi 2 jam. Persen yield yang di hasilkan pada kondisi optimum tersebut yaitu produk dari benzaldehida sebesar 85,11, dan produk dari sinamaldehida sebesar 90,14. Karakterisasi produk hasil sintesis dikonfirmasi dengan KLT, FTIR, spektrofotometer UV-Vis, dan GC-MS. Dari uji antioksidan didapatkan nilai IC50 untuk produk dari benzaldehida sebesar 5.966,92 ppm dan produk dari sinamaldehida sebesar 7.905,45 ppm. Katalis CuI merupakan katalis heterogen dengan ukuran nano yang dapat digunakan kembali. Pada penelitian ini nanokatalis CuI berhasil disintesis dengan ukuran rata-rata 78,44 nm. Karakterisasi nanokatalis dilakukan dengan FTIR, SEM-EDX, dan XRD. Nanokatalis CuI dapat digunakan kembali untuk sintesis turunan piridin, namun dapat mengalami penurunan aktivitas katalitik

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ABSTRACTPyridine derivative compounds is an important compound because it has applications in the field of bioactivity and pharmaceutical. The pyridine derivative compounds can be synthesized by Hantzsch method. Synthesis is carried out by reacting aldehyde, ethyl acetoacetate, and ammonium acetate with the help of CuI nanoparticles as catalysts. In this study, the synthesis of two pyridine derivative compounds was performed by varying the aldehyde benzaldehyde compound 1, cinnamaldehyde compound 2. The optimum condition obtained for the synthesis of this compound is by using ethanol solvent, using the amount of 10 mole catalyst, and with a reaction time of 2 h. Percent yield at the optimum condition from the product of benzaldehyde equal to 85.11, and from cinnamaldehyde equal to 90.14. Characterization of synthesis products with TLC, FTIR, UV Vis spectrophotometer, and GC MS. From the antioxidant test, IC50 value for the product from benzaldehyde was 5,966.92 ppm and product from cinnamaldehyde was 7,905.45 ppm. CuI catalysts are heterogeneous reusable catalysts with nano sizes. In this study, CuI nanocatalysts were successfully synthesized with an average size of 78.44 nm. Characterization of the nanocatalyst was performed with FTIR, SEM EDX, and XRD. The CuI nanocatalyst can be reused for synthesis of pyridine derivatives but may decrease catalytic activity."

"Penggunaan serat alami seperti serabut kelapa pada bahan semen memodifikasi sifat reologi dari bahan pada kondisi segar dan sifat mekanik pada kondisi keras. Sifat fisik dan kimia dapat mengubah interface antara serat dan matriks selama pengerasan. Pada penelitian ini dilakukan pengujian terhadap matriks dan serat yang digunakan. Kemudian dilakukan proses fabrikasi sampel. Langkah terakhir dipelajari pengaruh beban yang diterapkan pada matriks terhadap ikatan antara matriks dan serat. Hasil pengujian menunjukkan bahwa penambahan serabut dalam air yang digunakan dalam pasta menurunkan kekuatan matriks. Sedangkan adhesi antara makriks dengan serat meningkat seiring dengan meningkatnya konsolidasi matriks.

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The use of natural fibers such as coconut fiber in cementitious materials modifies the rheological properties of the fresh material and mechanical properties in the hardened state. Its physical and chemical properties can modify the interface between fiber and matrix during hardening. Initially the study and presentation of matrix and fiber used are provided. Then the process of samples fabrication is presented. In the last step, the influence of the load applied on the matrix to the adhesion between the matrix and fibers. Test results show that the addition of coir in the water used in the paste decreases the strength of matrix and the fiber-matrix adhesion increases with the growth of the matrix consolidation."

"This book presents the fabrication of optoelectronic nanodevices. The structures considered are nanowires, nanorods, hybrid semiconductor nanostructures, wide bandgap nanostructures for visible light emitters and graphene. The device applications of these structures are broadly explained. The book deals also with the characterization of semiconductor nanostructures. "