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""This book will cover the development and utilization of polymer films and coatings derived from non-petroleum, renewable resources from an applications perspective rather than being designed in the form of chapters in which individual polymers or polymer types are described. It will also include the topic of sustainability and how it is defined as well as a chapter on new developments in film production or coating technology in relation to existing technology (e.g., nanocomposites, plasma or corona treatment technology and lamination)"--"

"This reference work offers a comprehensive overview of the synthesis, properties and biomedical applications of functional biopolymers. Chapters from expert contributors cover topics such as synthetic biopolymers, blood-compatible polymers, ophthalmic polymers and stimuli responsive polymers. An up-to-date review of cell encapsulation strategies and cell surface and tissue engineering is also included in this work, and readers will discover more about hydrogels and polymers from renewable resources. Edited by an international team of experts in the field, this reference work will appeal to researchers, scientists, and practitioners working in this field, or entering this vibrant research area"

"Katalis heterogen akhir-akhir ini banyak digunakan untuk produksi biodiesel karena keuntungannya yang tidak membentuk sabun dan mudah dipisahkan dari reagennya. Nanokomposit selulosa-Fe3O4/ZnO yang telah berhasil disintesis didukung dengan karakterisasi menggunakan instrumen FT-IR, XRD, dan SEM. Selanjutnya, nanokomposit yang telah berhasil disintesis dilakukan uji aktivitas katalitik dalam reaksi pembentukan Biodiesel. Hasil dari pembentukan Biodiesel dikarakterisasi menggunakan instrumen GC-MS. Konversi minyak kelapa menjadi Biodiesel yang didapakan sebesar 90,6%, konversi terjadi pada suhu 70°C selama 120 menit ,dengan rasio molar minyak dan methanol sebesar 1:6 dan jumlah katalis 0,6% wt. Biodiesel yang berhasil terbentuk diuji dengan menggunakan instrument GC-MS dan dihasilkan persen area paling besar pada waktu retensi 12,653 menit yang menunjukan senyawa dodecanoic acid methyl ester ( lauric acid methyl ester). Evaluasi terhadap kinetika reaksi mengikuti persamaan pseudo orde pertama dengan konstanta laju reaksi (k) sebesar (0,0142 min-1), nilai konstanta laju reaksi dapat memberikan gambaran seberapa lama reaksi terjadi ketika digunakan konsentrasi reaktan yang lebih banyak untuk aplikasi dalam industri. Penggunaan selulosa sebagai support katalis dengan gabungan komposit Fe3O4/ZnO menjanjikan untuk menjadi katalis yang ramah lingkungan dalam reaksi pembentukan biodiesel.

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ABSTRACTHeterogeneous catalysts have been widely used for the synthesis of methyl esters because of their advantages which do not form soap and are easily separated from their reagents. The synthesized cellulose-Fe3O4/ZnO nanocomposite was successfully supported by characterization using FT-IR, XRD, and SEM instruments. Furthermore, nanocomposites that have been successfully synthesized were tested for catalytic activity in the reaction of biodiesel formation. The results of the formation of biodiesel were characterized using GC-MS instruments. Conversion of coconut oil to biodiesel is obtained by 90.6%, conversion occurs at 70 °C for 120 minutes, with a molar ratio of oil and methanol of 1: 6 and the amount of catalyst 0,6% wt. biodiesel that were successfully formed were tested using GC-MS instruments and the largest percent area was produced at a retention time of 12,653 minutes which showed dodecanoic acid methyl ester (lauric acid methyl ester) compounds. Evaluation of reaction kinetics follows the first-order pseudo equation with a reaction rate constant (k) of (0.0142 min- 1), the value of the reaction rate constant can give an idea of how long the reaction occurs when more concentrated reactants are used for industrial applications. The use of cellulose as a catalyst support with composite Fe3O4/ZnO promises to be an environmentally friendly catalyst in the reaction of biodiesel formation."

"This book gives an introduction to molecular biophysics. It starts from material properties at equilibrium related to polymers, dielectrics and membranes. Electronic spectra are developed for the understanding of elementary dynamic processes in photosynthesis including proton transfer and dynamics of molecular motors. Since the molecular structures of functional groups of bio-systems were resolved, it has become feasible to develop a theory based on the quantum theory and statistical physics with emphasis on the specifics of the high complexity of bio-systems. This introduction to molecular aspects of the field focuses on solvable models. Elementary biological processes provide as special challenge the presence of partial disorder in the structure which does not destroy the basic reproducibility of the processes. Apparently the elementary molecular processes are organized in a way to optimize the efficiency. Learning from nature by means exploring the relation between structure and function may even help to build better artificial solar cells. The reader is exposed to basic concepts in modern biophysics, such as entropic forces, phase separation, potential of mean force, electron and proton transfer, heterogeneous reactions, coherent and incoherent energy transfer as well as molecular motors. Basic knowledge in classical and Quantum mechanics, electrostatics and statistical physics is desirable. Simplified models are presented which can be solved in limited cases analytically from the guiding lines to generate the basis for a fundamental understanding of the more complex biophysical systems. Chapters close with challenging problems whose solutions are provided at the end of the book to complete the pedagogical treatment in the book.To the second edition several new chapters were added. The medium polarization is treated self-consistently using basic elements of polaron theory and more advanced nonlinear Schrödinger equations to describe the dynamics of solvation. Ion transport through a membrane was extended by the discussion of cooperative effects. Intramolecular transitions are now discussed in the new edition in much more detail, including also radiationless transitions. Very recent developments in spectroscopy are included, especially two-dimensional and hole-burning spectroscopy. The discussion of charge transfer processes was extended by including recent results of hole transfer in DNA in connection with the super-exchange mechanism. The chapter on molecular motors was rewritten to include the most recent developments of new models. The book is a useful text for students and researchers wanting to go through the mathematical derivations in the theories presented. This book attracts a group of applied mathematically oriented students and scholars to the exciting field of molecular biophysics. "

"Turunan formula Navier-Stokes dipakai untuk menghitung kerugian tekanan aliran dalam pipa. Panjang pipa, diameter pipa, kecepatan fluida, kekasaran permukaan dan koefisien gesek yang mempengaruhi nilai kerugian tekanan. Formula tersebut tidak berlaku pada belokan/cabang pipa, setelah katup, adanya perubahan diameter (unsteady flow), adanya getaran, dll. Drag reduction dari solusi surfactant atau biopolymer telah menarik perhatian dari sisi konversi energy, dikarenakan penurunan secara mekanis tidak terjadi tetapi menghasilkan drag reduction yang besar di kondisi konsentrasi tertentu oleh karena itu solusi biopolymer banyak digunakan pada system pemipaan dan hasil percobaan dilapangan menunjukan penurunan dari tenaga yang dibutuhkan pompa mencapai 30% dari kecepatan aliran normal Penelitian ini bertujuan untuk membuktikan efek panjang aliran terhadap aliran berkembang penuh dengan membandingkan 3 macam fluida yaitu air murni ; biopolimer air tape ketan 100 ppm dan biopolimer air tape ketan 250 ppm. Di mana biopolimer merupakan hasil fermentasi beras. dan membuktikan keterbatasan penggunaan formula Navier-Stokes. Eksperimen ini menggunakan pipa acrylic berdiameter 12 mm. Variasi panjang pipa masuk terhadap titik pengukur tekanan (pressure tap) yaitu dengan menggeser pipa kecil masuk kedalam pipa uji hingga keadaan fluida mencapai kondisi berkembang penuh. Pada pipa uji dipasang 4 buah pressure tap dengan jarak masing-masing tap 250 mm. Air murni sebagai fluida uji. Debit yang keluar diukur dengan gelas ukur pada periode waktu untuk mendapatkan nilai bilangan Reynolds. Hasil menunjukkan bahwa karakteristik panjang aliran berkembang penuh untuk fluida dengan campuran konsentrasi biopolymer lebih besar dibandingkan dengan air murni.

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Navier-Stokes equations derived formula used to calculate the pressure loss in pipe flow. The length of the pipe, the pipe diameter, the fluid velocity, surface roughness and coefficient of friction that affect the value of pressure loss. The formula does not apply to the branch / branch pipes, the valves, the change in diameter (unsteady flow), the presence of vibration, etc.. Drag reduction of surfactant solution or a biopolymer has attracted attention from the conversion of energy, due to a mechanical reduction does not occur but produced a large drag reduction in a specific concentration of condition therefore biopolymer solutions are widely used in piping systems and field experimental results show a decrease of available power pumps needed to reach 30% of normal flow velocity.

This study aims to prove the effect of flow length to the flow is fully developed by comparing three kinds of fluid that is pure water, 100 ppm biopolymer and 250 ppm biopolymer. Where biopolymer is fermented rice and prove the limitations of the use of the Navier-Stokes formula. These experiments using 12 mm diameter acrylic pipe. Length variation on the point of intake pressure gauge (pressure tap) that is by sliding a small pipe into the test tube until the fluid reaches the state is fully developed conditions. In test tube fitted with a pressure tap four fruit each tap distance 250 mm. Pure water as test fluid. The exit discharge is measured with a measuring cup in the period of time to get the value of Reynolds number. Results showed that the characteristic length for the fluid flow is fully developed with a mixture of biopolymer concentration greater than pure water. "