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"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."

"Residual stresses are a common phenomenon in composite materials. They can either add to or significantly reduce material strength. Because of the increasing demand for high-strength, light-weight materials such as composites and their wide range of applications in the aerospace and automotive industries, in civil infrastructure and in sporting applications, it is critical that the residual stresses of composite materials are understood and measured correctly.The first part of this important book reviews destructive and non-destructive testing (NDT) techniques for measuring residual stresses. Various mathematical (analytical and numerical) methods for calculation of residual stresses in composite materials are also presented. Chapters in the first section of the book discuss the simulated hole drilling method, the slitting/crack compliance method, measuring residual stresses in homogeneous and composite glass materials using photoelastic techniques, and modeling residual stresses in composite materials. The second part of the book discusses residual stresses in polymer matrix, metal-matrix and a range of other types of composites. Moreover, the addition of nanoparticles to the matrix of polymeric composites as a new technique for reduction of residual stresses is discussed."

"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."

"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."

"Polimer Blend (PB) merupakan s-alah satu alternatif dalam rangka mezuingkatkan laju perkembangan ilmu bahan. PB ~PP/PS adalah salah satu jenis polimer blend yang sedang dikembangkan, namun sayangnya, bahan PB ini memiliki sifat mekanjk yang kurang n1enguntungkan_ Hal ini dilcarenakan mereka memiliki sifat daya adhesi yang km-ang baik pada daerah antar permukaan fasanya, sehingga menghalangi perpindahan tegangan-tegangan antar fasa-fasa. Selain itu, mereka umumnya memiliki tegangan antar permukaan yang relatif besar sehingga fasa-fasa yang terdispersi memiliki ukuran yang relatif besar pula. Oleh karena itu, dalam penelitian ini dilakukan penambahan Sant0prene°, sebagai zat pemantap (compatibilizer agent) dengan harapan sifat-sifat mekanik bahan PB ini dapat meningkat. Dalam penelitian ini, dilakukan pengamatan terhadap sifat-sifat mekanik bahan PB (PP/20%PS) akibat penambahan konsentrasi berat Santoprene° sebesar 0%. 5%, 10%, 15%, dan 20%, guna mengetahui bagaimana pengaruh penambahan Santoprene° tersebut terhadap sifat-sifat mekanik PB ini dan sifat aclhesi antar permukaan fasanya. Adapun sifat-sifat mekanik yang diamari adalah kekuatan tarik (MPa), elongasi saat putus (%), kekuatan irnpak (I/rn), kekerasan (Rockwell R), tegangan maksimum Heksural (MPa), dan modulus elastisitas Heksural (GPa). Selain itu, dilakukan pula pengamatan terhadap sl-rukl-ur mikro hasil campuran dengan bantuan scanning electron microscope (SEM). Dari hasil penelitian ini diperoleh kesimpulan bahwa sifat kekuatan impak dan elongasi bahan PB (PP/20%PS) + X%Santoprene° rneningkat seiring dengan meningkatnya konsentrasi berat Santoprene°. Namun di pihak lainnya, bahan PB (PP/2D%PS) +X% Santoprene° ini mengalami penumnan sifat kekuatan tari.k, fleksural, kekerasan, dan kekakuarmya seiring dengan bertambahnya komposisi Santoprene°. Walaupun Sa.ntoprene° telah dapat meningkatkan sifat kekuatan impak dan elongasi bahan PB PP/ PS, Santoprene° belum dapat memperbaiki sifat antar perrnukaan fasa dalam bahan ini."

"Gas merupakan energi transisi yang mampu menekan emisi karbon sehingga dapat menyebabkan perubahan iklim. Pengembangan lapangan gas merupakan implementasi transisi energi sebelum menuju energi baru terbarukan (EBT). Lapangan Natuna D Alpha dengan kandungan CO₂ sebesar 71% dan CH₄ 28%. Sehubungan hal tersebut perlu dilakukan studi untuk membuat gas bumi terproduksi sesuai dengan spesifikasi gas jual. Studi pengembangan lapangan gas ini meninjau dari aspek teknis dan aspek keekonomian yang disebut dengan metode Tekno-Eknomi. Aspek teknis melakukan simulasi teknik membran dengan material polimer tipe Polysulfone dengan rumus matematis kedalam Python dan hasil dari Python dimasukkan kedalam unisim. Teknologi membran untuk memisahkan CO₂ dari gas bumi. Selanjutnya melakukan injeksi CO₂ kembali kebawah permukaan bumi sebagai penerapan carbon capture storage & utilization dengan ruang lingkup menghitung kapasitas penyimpanan CO₂ sequestration dan enhanced gas recovery Sedangkan, pada aspek keekonomian sebagai penentuan  kelayakan proyek dengan menggunakan skema production sharing contract cost recovery yakni Pemerintah dan Kontraktor. Hasilnya mampu memurnikan CH₄ hingga 95,02% dengan kandungan CO₂ sebesar 4,89% dengan nilai investasi sebesar 5.451.869 MUSD. Aspek keekonomian Pengembangan lapangan gas Natuna D Alpha dapat lanjut ketahap eksekusi dengan net present value sebesar 2.595.638 MUSD, kemudian  internal rate of return sebesar 13,84%, dan payback periode pada tahun ke 7,05.

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The gas is an energy transition that can reduce carbon emissions cause its climate change. Implementation of energy transition by plan of gas field development (POFD). The Natuna D Alpha Field with 71% of CO₂ content and 28% of CH₄ content. It is necessary to study upgrading natural gas specification in accordance with the sales gas specifications. Natuna D Alpha development study using Techno-Economics method. For technical aspect, we design polymer membrane technology with Polysulfone  into Python then input to unisim.  Membrane technology is to separate CO₂ from natural gas. Furthermore, CO₂ captured will re inject to subsurface as the implementation of carbon capture storage & utilization  through estimating CO₂ storage capacity for sequestration and enhanced gas recovery . Meanwhile, the economic aspect is to determine project feasibility using a production sharing contract cost recovery scheme, whose are the Government and the Contractor. The result is 95,02% of CH₄ content with 4,89% of CO₂ content. It needs investment cost of 5.451.869 MUSD. Based on the economic aspect Natuna D Alpha gas field development can proceed to the execution stage that determined net present value (NPV) of USD 24,960 million then IRR is about 13,84%, Payback Period (PBP) in 7,05 year.

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"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."

"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."

"One of the critical issues in semiconductor technology is the precise electrical characterization of ultra-shallow junctions. Among the plethora of measurement techniques, the optical reflectance approach developed in this work is the sole concept that does not require physical contact, making it suitable for non-invasive in-line metrology. This work develops extensively all the fundamental physical models of the photomodulated optical reflectance technique and introduces novel approaches that extend its applicability from dose monitoring towards detailed carrier profile reconstruction. It represents a significant breakthrough in junction metrology with potential for industrial implementation."