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"Struktur nano ZnO merupakan salah satu material semikonduktor yang banyak diteliti untuk diaplikasikan dalam devais optoelektronik, fotokatalis dan sensor. Dalam penelitian ini dilakukan proses sintesis nanorod ZnO diatas substrat kaca yang terdiri dari dua tahap yaitu proses pembenihan dengan metode ultrasonic spray pyrolysis dan proses penumbuhan nanorod ZnO dengan metode hidroterma l dengan bantuan gelombang mikro. Fokus penelitian ini adalah mengamati pengaruh konsentrasi bahan penumbuh hexamethyelenentetramine dan zinc nitrate tetrahydrate 0,05 M, 0,1 M dan 0,15 M. Dari hasil SEM, XRD dan UV-Vis menunjukkan bahwa penambahan konsentrasi larutan penumbuh mengakibatka n peningkatan parameter kisi, volume unit sel, ukuran kristalit dari 268 menjadi 426 hingga diameter nanorod dari 89-183 nm menjadi 118-216 nm, serta peningkatan band gap dari 3,20 eV menjadi 3,22 eV. Larutan penumbuh dengan konsentrasi 0,15 M merupakan konsentrasi prekursor terbaik karena dapat menghasilkan absorbansi ultraviolet yang paling tinggi.

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ZnO nanostructure is one of the most studied semiconductor materials for optoelectronic devices, photocatalysts and sensors applications. One way to accelerate the reaction is using microwaves. In this research, ZnO nanorods were grown on glass substrates via seeding process via ultrasonic spray pyrolysis method and growth process via hydrothermal method. The focus of this study is to observe the effect of growth solution concentration of hexamethyelenentetramine and zinc nitrate tetrahydrate 0,05 M, 0,1 M and 0,15 M on the morphology, microstructure and optical properties of ZnO nanorods.

By using Scanning Electron Microscoupe SEM, x ray diffraction XRD and UV VIS spectrometers it is seed that an increase of growth solution concentration resulted in the increases of lattice parameters, unit cell volume, crystallite size of 268 to 426 , and diameter of ZnO nanorods from 89 183 nm to 118 216 nm. And also increase the band gap from 3,20 eV to 3,22 eV. Growth solution with a concentration of 0.15 M is the best precursor concentration as it could produce the highest ultraviolet absorbance."

"Lectures : G. Toraldo di Francia, lezioni sulla teoria della diffrazione elettromagnetica. C.J. Bouwkamp, theorie des multipoles, de l'antenne et de la diffraction des ondes. Seminars, G. Eckart, sur le fading des ondes ultracourtes et son analyse. G. Agostinelli, sulla teoria delle guide d´onda. D. Graffi, guide d´onda con dielettrico eterogeneo."

"Penggunaan kalsium fosfat sebagai bahan pengganti tulang sudah banyak diaplikasikan, khususnya pengaplikasian hidroksiapatit karena kemiripannya dengan mineral tulang manusia. Hidroksiapatit merupakan senyawa kalsium fosfat yang paling stabil dan telah banyak digunakan sebagai implan tulang, namun hidroksiapatit memiliki sifat brittle yaitu mudah rapuh dan mempunyai sifat resorbabilitas yang sangat rendah. Untuk memenuhi kebutuhan biomaterial pada jaringan tulang, selain mineral diperlukan material organik sebagai penyusun matriks. Salah satu yang dapat digunakan adalah kolagen yang merupakan protein fungsional yang ada didalam tubuh dan memiliki peran penting dalam menjalankan fungsi tubuh. Kombinasi antara hidroksiapatit dan kolagen memiliki potensi untuk rekayasa jaringan tulang karena kesamaan dan sifat biologis alaminya. Pada penelitian ini komposit hidroksiapatit/kolagen disintesis secara In-situ menggunakan metode iradiasi gelombang mikro dengan daya sebesar 400 Watt selama 10, 20, dan 30 menit. Penggunaan iradiasi gelombang mikro digunakan karena dapat memicu pertumbuhan kristal hidroksiapatit dengan waktu yang relatif cukup singkat dibandingkan dengan metode konvensional seperti konduksi dan konveksi. Pada hasil karakterisasi menggunakan difraksi sinar-x didapatkan pola puncak puncak yang mengindikasikan terbentuknya fasa hidroksiapatit yang di berada pada sudut 2θ 25°, 28°, 32°, 39°, 53° dan bidang miller (002), (210), (300), (310), (004) pada seluruh komposit yang di iradiasi selama 10, 20, dan 30 menit serta diperoleh ukuran kristal sebesar 21,94 - 22,65 nm serta indeks kristalinitas sebesar 0,269 - 0,297. Hasil ini menujukan bahwa semakin lama waktu radiasi yang diberikan maka ukuran kristal serta nilai indeks kristalinitas juga meningkat. Hasil karakterisasi FTIR menandakan adanya karakteristik serapan dari hidroksiapatit dan kolagen pada komposit yang ditandai dengan terdapatnya gugus fosfat (PO4) pada bilangan gelombang 564 cm-1, 603-602 cm-1, 1032 cm-1 dan 961-962 cm-1, gugus karbonat (CO3) pada bilangan gelombang 875-876 cm-1, gugus hidroksil (OH) pada bilangan gelombang 3566 cm-1, Amida A (N-H) pada bilangan gelombang 3423-3442 cm-1, Aminda B (C-H) pada bilangan gelombang 2963-2964 cm-1, Amida I (C=O) pada bilangan gelombang 1646-1650 cm-1, Amida II (N-H) pada bilangan gelombang 1540-1542 cm-1 serta Amida III (C-H) pada bilangan gelombang 1260-1263 cm-1. Hasil karakterisasi menggunakan SEM memperlihatkan bahwa hidroksiapatit telah terpresipitasi dan menyelimuti pori kolagen.

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Calcium phosphate has been widely applied as a bone substitute, especially hydroxyapatite, because of its similarity with human bone minerals. Hydroxyapatite is the most stable calcium phosphate compound, However, hydroxyapatite has brittle properties and very low resorbability. To meet the biomaterials needs of bone tissue, in addition to minerals, organic materials are needed as matrix compounds. Collagen, a functional protein found in the body, can fulfill this role. A hydroxyapatite and collagen combination has the potential to be engineered into bone tissue because of its similarity and natural biological properties. In this study, the hydroxyapatite/collagen composite was synthesized in situ using the microwave irradiation method with a power of 400 Watt for 10, 20, and 30 minutes. Microwave irradiation is used because it can trigger the growth of hydroxyapatite crystals in a relatively short time compared to conventional methods, such as conduction and convection. In the results, using x-ray diffraction, the peak pattern showed the formation of the hydroxyapatite phase indicated at an angle of 2θ 25°, 28°, 32°, 39°, 53° and the miller indices (002), (210), (300), (310), (004) in all composites that were irradiated for 10, 20, and 30 minutes obtained a crystal size of 21.94 nm - 22.65 nm, and a crystallinity index of 0.269 - 0.297. This shows that the longer the composite is exposed to radiation, the crystal size, and value of the crystallinity index also increase. The results of the use of FTIR shows the absorption characteristics of hydroxyapatite and collagen in the composite that were characterized by the presence of a phosphate group (PO4) on wavenumber 564 cm-1, 603-602 cm-1, 1032 cm-1 and 961-962 cm-1, a carbonate group (CO3) on wavenumber 875-876 cm-1, a hydroxyl group (OH) on wavenumber 3566 cm-1, Amide A (N-H) on wavenumber 3423-3442 cm-1, Amide B (C-H) on wavenumber 2963-2964 cm-1, Amide I (C=O) on wavenumber 1646-1650 cm-1, Amide II (N-H) on wavenumber 1540-1542 cm-1, Amide III (C-H) on wavenumber 1260-1263. Characterization using SEM showed that hydroxyapatite had precipitated and covered the collagen pores."

"Biomaterial pada rekayasa jaringan tulang harus memenuhi karakteristik yaitu biokompatibilitas, efektivitas, dan non-toksisitas. Penelitian ini bertujuan untuk mempelajari karakteristik komposit hidroksiapatit dan fibroin sutra dengan dan tanpa gelatin yang disiapkan dengan ex-situ berbantukan iradiasi gelombang mikro. Pengujian karakterisasi yang dilakukan pada penelitian ini adalah X-Ray Diffraction, Fourier Transform Infared, dan Scanning Electron Microscopy. Pengujian mekanik yang dilakukan pada penelitian ini adalah micro-Vickers. Hasil XRD menyatakan ukuran kristalin pada sampel HA80/SF20/Gel5% bernilai 166 Å sedangkan pada sampel HA70/SF30/Gel5% bernilai 134 Å. Hal ini menunjukkan bahwa pelebaran puncak dipengaruhi oleh ukuran kristalin. Karakteristik FTIR untuk gugus fungsi pada sampel HA70/SF30/Gel5% lebih lemah dibandingkan dengan HA70/SF30, artinya kandungan H2O HA70/SF30/Gel5% lebih rendah daripada HA70/SF30. Selanjutnya hasil analisis morfologi permukaan didapatkan partikel aglomerat dengan pori-pori yang saling berhubungan serta penambahan gelatin dapat menyebabkan aglomerasi partikel berbentuk serpihan. Pada hasil uji micro-Vickers menunjukkan dugaan sementara bahwa gelatin dalam komposit HA/SF/Gel mengakibatkan nilai kekerasan semakin tinggi, yaitu pada HA70/SF30/Gel5% dengan nilai 0,049 Hv.

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Biomaterials in bone tissue engineering must meet the characteristics, namely biocompatibility, effectiveness, and non-toxicity. This research aims to study the characteristics of hydroxyapatite and silk fibroin composites with and without gelatin prepared by ex-situ assisted by microwave irradiation. The characterization tests carried out in this research were X-Ray Diffraction, Fourier Transform Infrared, dan Scanning Electron Microscopy. The mechanical tests carried out in this research were micro-Vickers. The XRD results show that the crystalline size in the HA80/SF20/Gel5% sample is 166 Å, while in the HA70/SF30/Gel5% sample it is 134 Å. This shows that peak broadening is influenced by crystalline size. The FTIR characteristics for functional groups in the HA70/SF30/Gel5% sample are weaker than those of HA70/SF30, meaning that the H2O HA70/SF30/Gel5% lower than HA70/SF30. Furthermore, the results of surface morphology analysis showed agglomerate particles with interconnected pores and the addition of gelatin could cause agglomeration of flake-shaped particles. On test results micro-Vickers shows a temporary assumption that gelatin in the HA/SF/Gel composite results in a higher hardness value, namely at HA70/SF30/Gel5% with a value of 0,049 Hv."

"Detailed tutorials are included on all major topics required to understand fundamental principles behind both the main sub-circuits required to design an RF transceiver and the whole communication system. Starting with review of fundamental principles in electromagnetic (EM) transmission and signal propagation, through detailed practical analysis of RF amplifier, mixer, modulator, demodulator, and oscillator circuit topologies, all the way to the system communication theory behind the RF transceiver operation."

"Modeling, simulation, design and engineering of WDM systems and networks provides readers with the basic skills, concepts, and design techniques used to begin design and engineering of optical communication systems and networks at various layers. The latest semi-analytical system simulation techniques are applied to optical WDM systems and networks, and a review of the various current areas of optical communications is presented. Simulation is mixed with experimental verification and engineering to present the industry as well as state-of-the-art research. This contributed volume is divided into three parts. The first part of the book presents modeling approaches and simulation tools mainly for the physical layer including transmission effects, devices, subsystems, and systems), whereas the second part features more engineering/design issues for various types of optical systems including ULH, access, and in-building systems. The third part of the book covers networking issues related to the design of provisioning and survivability algorithms for impairment-aware and multi-domain networks."

"Recent technological breakthrough in the field of Terahertz radiation has triggered new applications in biology and biomedicine. Particularly, biological applications are based on the specific spectroscopic fingerprints of biological matter in this spectral region. Historically with the discovery of new electromagnetic wave spectrum, we have always discovered new medical diagnostic imaging systems. The use of terahertz wave was not realized due to the absence of useful terahertz sources. Now after successful generation of THz waves, it is reported that a great potential for THz wave exists for its resonance with bio-molecules.There are many challenging issues such as development of THz passive and active instrumentations, understanding of THz-Bio interaction for THz spectroscopy, THz-Bio nonlinear phenomena and safety guideline, and THz imaging systems. Eventually the deeper understanding of THz-Bio interaction and novel THz systems enable us to develop powerful THz biomedical imaging systems which can contribute to biomedical industry.This is a truly interdisciplinary field and convergence technology where the communication between different disciplines is the most challenging issue for the success of the great works. "

"The research described here develops and applies novel, ultra-wideband (UWB) antipodal Vivaldi antennas for high-resolution detection of defects and damages in composite construction materials and structures using their microwave and millimeter wave imaging. The author examines the challenges of applying the UWB microwave technique in that the technique is dependent on the operating frequency used for the specified material under test. In this context, the objectives of this research volume include, but are not limited to, development of a small UWB antenna at frequency range from 5 GHz-50 GHz for microwave and millimeter wave imaging of wide range of low loss construction materials, design of a small UWB antenna operating for microwave and millimeter wave imaging of low loss and high loss materials for the purpose of detection of surface damages of concrete under low loss materials, and development of a UWB antenna at frequency range from 2 GHz-27 GHz for microwave imaging of low loss and high loss materials such as concrete structures and layered structures for the purpose of detection of cavities inside concrete.;"