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"Covering more than 7,800 organic and inorganic chemicals and hydrocarbons, Transport properties of chemical and hydrocarbons, second edition is an essential volume for any chemist or chemical engineer. Spanning gases, liquids, and solids, the book covers all critical properties (including viscosity, thermal conductivity, and diffusion coefficient).From C1 to C100 organics and Ac to Zr inorganics, the data in this handbook is a perfect quick reference for field, lab, or classroom use. By collecting a massive – but relevant – amount of information in one source, the handbook enables engineers to spend more time developing new designs and processes, and less time collecting vital properties data."

"The series of hybrid organic-inorganic silica materials have been prepared by introducing organic ligands materilas based on sol-gel processing of alkoxysilanes for potential applications in membrane design for pervaporation....."

"Buku yang berjudul "Handbook on semiconductors : band theory and transport properties" ini merupakan sebuah buku panduan mengenai semikonduktor. "

"Poliuretan merupakan senyawa polimer tersegmentasi oleh hard segment dan soft segment. Modifikasi lanjut dari poliuretan memungkinkan untuk dijadikan produk busa, dengan berbagai macam sifat. Busa poliuretan memiliki kecenderungan bersifat rigid maupun fleksibel, dengan pengaturan oleh rasio segmen serta penambahan chain extender selama proses sintesis. Bahan dasar yang digunakan dalam sintesis busa bio-poliuretan yaitu Polipropilen Glikol (PPG) 2000, Toluene Diisosianat 80 (TDI 80), katalis Amina, katalis Tin, surfaktan, dan penambahan biomassa lignin sebagai chain extender dan sebagai variabel bebas dari penelitian ini dengan variasi penambahan 1, 2, 3 pbw. Metode sintesis yang digunakan ialah one shot method. Untuk mengetahui sifat penambahan chain extender lignin, maka dilakukan pengujian antara lain uji tarik, uji morfologi, uji kandungan senyawa dan uji stabilitas termal. Dari sintesis yang dilakukan, didapat busa bio-poliuretan dengan bentuk pori tertutup. Memiliki kekuatan tarik meningkat, namun sifat elongasi yang cenderung menurun seiring dengan bertambahnya biomassa lignin yang ditambah. Dari pengujian stabilitas termal, didapat bahwa, penambahan biomassa lignin memberikan efek stabilitas termal yang lebih baik dari PUF-Virgin jika dilihat dari perilaku degradasi yang terjadi selama pemanasan.

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Polyurethane is a polymer compound segmented by hard segment and soft segment. Further modifications of polyurethane make it possible to make foam products, with a variety of properties. Polyurethane foam has a tendency to be rigid and flexible, by adjusting the segment ratio and adding chain extenders during the synthesis process. The basic ingredients used in bio-polyurethane foam synthesis are Polypropylene Glycol (PPG) 2000, Toluene Diisocyanate 80 (TDI 80), Amine catalyst, Tin catalyst, surfactant, and the addition of lignin biomass as a chain extender and as independent variables of this study with variations addition of 1, 2, 3 pbw. The synthesis method used is one shot method. To determine the nature of the addition of the lignin chain extender, tests were carried out including tensile test, morphological test, compound content test and thermal stability test. From the synthesis carried out, bio-polyurethane foam with closed pore shape was obtained. It has increased tensile strength, but the nature of elongation tends to decrease with increasing lignin biomass. From testing thermal stability, it was found that, the addition of lignin biomass had a better thermal stability effect than PUF-Virgin when viewed from the degradation behavior that occurred during heating."

"Sifat transportasi elektron di molekul DNA poly dA -poly dT telah dipelajari. Kami menggunakan dua model DNA yang berbeda, yang direpresentasikan secara matematis dengan model ikatan kuat Hamiltonian dan teori Slater-Koster. Panjang molekul DNA yang digunakan 32 pasangan basa. Kedua ujung rantai molekul dikoneksikan dengan elektroda. Sifat transportasi elektron dipelajari dari probabilitas transmisi dan karakteristik I-V. Probabilitas transmisi dihitung dengan metode transfer matriks dan matriks hamburan. Formula Landauer Buttiker digunakan untuk menghitung karakteristik I-V. Selanjutnya, sifat transportasi elektron dibandingkan di variasi temperatur, frekuensi getar gerak memutar dan energi gangguan lingkungan luar. Hasilnya menunjukan bahwa pada kedua model mengalami peningkatan probabilitas transmisi elektron dan arus seiring meningkatnya frekuensi getar gerak memutar rantai DNA. Namun saat temperatur ditingkatkan, probabilitas transmisi dan arusnya menurun dan tegangan ambang membesar di tiap variasi frekuensi getar. Kemudian ketika energi gangguan luar meningkat, probabilitas transmisi dan arus semakin kecil, demikian pula tegangan ambangnya. Nilai puncak-puncak probabilitas transmisi di model B lebih besar dari model A, namun kurva I-V model B dapat lebih besar atau lebih kecil. Peningkatan maupun penurunan transmisi dan arus di model A lebih besar ketika tidak ada gangguan backbone, tendensi terbalik ketika terdapat energi gangguan backbone.

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The properties of electron transport in poly dA poly dT DNA molecules have been studied. We use two models of DNA which are represented mathematically by tight binding Hamiltonian model and Slater Koster theory. DNA molecules which are used have 32 base pairs long. Each end of DNA chain are connected to metallic electrodes. The properties of electron, are studied from transmission probability and I V characteristic curves. The transmission probabilities are calculated using transfer matrix and scattering matrix methods. The Landauer Buttiker formula is used in computing I V characteristics. The properties of transport electron are compared in variation of temperatures, frequencies of twisting motion and disorder energy due to environment. The results show that the transmission probability and current values increase as frequency of twisting motion increases in both of models. However, as temperature become higher, the transmission probability and current values decrease, but the treshold voltages increase for all frequency variations. Then, as disorder energy becomes higher, the transmission probability and current values decrease, and the threshold voltages decrease, too. Transmission probability values of model B are higher than model A, but the I V curve of model B can be higher and lower. Both of the enhancement or reduction of transmission and current in model A is higher for without backbone disorder energy condition, but the tendency reversed when in backbone disorder energy condition."

"Diantara tiga struktur TiO₂, anatase TiO₂ telah mendapat banyak perhatian karena sifatnya yang menarik serta potensinya untuk dimanfaatkan dalam berbagai aplikasi. Berbagai aplikasi tersebut bergantung pada sifat transpor material ini. Beberapa penelitian terdahulu mengenai sifat transport anatase TiO₂ menunjukkan adanya kopling antara elektron dan fonon yang membentuk suatu kuasi partikel bernama polaron. Namun, belum ada penjelasan mengenai bagaimana keberadaan polaron pada anatase TiO₂ mempengaruhi sifat transpor terutama resistivitas. Oleh karena itu, kami melakukan studi teoretik terhadap sifat transport anatase TiO₂ yang dipengaruhi oleh kehadiran polaron. Kami menggunakan model Holstein, di mana menggunakan dua pita anatase TiO₂ yaitu pita konduksi dan pita valensi yang diselesaikan dalam kerangka Dynamical Mean Field Theory (DMFT) untuk menjelaskan interaksi antar elektron dan fonon. Kami menghitung densitas keadaan sistem dan nilai dari invers kuadrat dari densitas keadaan yang berkorespondensi pada potensial kimia, di mana nilai ini sebanding dengan nilai resistivitas, sebagai fungsi temperatur. Dengan menggunakan nilai densitas pembawa muatan seperti pada eksperimen, hasil perhitungan menunjukkan pada resistivitas turun seiring dengan pertambahan temperatur pada seluruh nilai densitas pembawa muatan. Hal ini menunjukkan bahwa model yang digunakan hanya baik dalam mendeskripsikan efek trapping namun kurang baik dalam menjelaskan efek hamburan.

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We present a theoretical study on the effects of electron-phonon interactions on the transport properties of anatase TiO₂. Temperature-dependent resistivity measurement on anatase TiO₂ thin film has shown that carrier concentrations and temperatures affect the resistivity of this material. At low carrier concentrations, a metal to insulator transition could be observed, while at high carrier concentrations this material only shows metal-like resistivity. In this study we aim to investigate the behavior of temperature-dependent resistivity at various carrier concentrations as revealed in the experimental study. We hypothesize that electron-phonon interactions with intermediate coupling constant govern the transport properties of this material. We construct Holstein model Hamiltonian incorporating both conduction and valence bands of anatase TiO₂ within parabolic dispersion approximation. We solve the model within the Dynamical Mean Field Theory (DMFT). We calculate the density of states of the system and the corresponding inverse of the square of the density of states at the chemical potential, which is approximately proportional to the resistivity, as a function of temperature. Using carrier concentration values taken as in the experimental data, the calculations show that only the trends of decreasing resistivity with increasing temperature is found in all carrier concentrations value. The results show that our model is good in the describing the trapping effects due to the electron-phonon interaction but the model is doing poorly in capturing the scattering effects."