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"The aim of this study was to synthesize high luminescence materials containing the optimal combination of ternary europiumpicrate complex and matrices. The ternary europium-picrate-triethylene glycol (Eu-EO3-Pic) complex was doped in poly(methyl methacrylate), PMMA. The composites were impregnated in several matrices to form thin filmsvia spin coating technique. The microparticles of Eu-EO3-Piccomplex were prepared by reprecipitation-evaporation, then they were compared to analogous complex or microcomposite prepared by in-situ method. The Eu-EO3-Pic/PMMA microcomposites were characterized by fluorescence spectroscopy in acetone solution. The particle sizes distribution of microcomposites synthesized by reprecipitation-evaporation method (110.3 to 426.8 nm) were smaller compared to the microcomposites by in-situ method (641.7 nm). The PMMA was able to significantly enhance the fluorescence intensity of Eu-EO3-Pic microparticles. The fluorescence intensity of microcomposite by in situ-preparation was lower than that found in the microcomposites by reprecipitation-evaporation method. We also investigated the effect of different matrices on the photophysical properties. The effective intermolecular energy transfer from PMMA to the Eu-EO3-Pic complex would produce high sensitization efficiency. These microcomposites are very potential used as the emission material for organic light emitting devices."

"Triethylene glycol dimethacrylate (TEGDMA) is a common component of the bonding agents and resin composites used in dentistry for restorative dentistry. However, TEGDMA could be released from composite resins following incomplete polymerization and degradation processes by salivary enzymes in the mouth. Subsequently, TEGDMA is available in saliva and diffuses toward and affects the dental pulp which contains various cells, and thus may cause severe cytotoxic effects. Objectives: To determine the total protein concentration of human dental pulp cells following exposure to TEGDMA. Materials & methods: Dental pulp cells were isolated from the pulp of the freshly extracted teeth and cultured in DMEM for 48 h (37°C, 5% CO2). Then, 2 mM, 4mM and 8 mM TEGDMA were added to these cells and incubated for 24 h. The total protein was measured by Bradford Protein Assay. Results: The total protein concentration of dental pulp cell after expsured to 4 mM, 8mM, and 12 mM TEGDMA were statistically lower (22762.27 ug/ml ± 3385.87; 20268.44 ug/ml ± 1701.14; 23706.51 ug/ml ± 3214.52; respectively) than the control group (24253.77 ug/ml ± 3072.88). Furthermore, the total protein concentration of culture medium after exposured to 4 mM, 8mM, and 2 mM TEGDMA, were statustically higher (28635 ug/ml ± 2373.4; 35288.41 ug.ml ± 3469.48; 38199.79 ug/ml ± 2752.47; respectively) when compared with the controls (27073.85 ug/ml ± 2772.47). Conclusion: 2 mM, 4 mM, and 8 mM TEGDMA caused cytotoxicity to human dental pulp cells showed by decreasing the total protein of cells and increasing total protein of the culture medium."

"Lapangan gas X merupakan lapangan produksi gas alam yang memiliki produk samping berupa CO₂. Dikarenakan sifatnya yang korosif dan dapat menurunkan nilai jual gas, gas tersebut umumnya akan dibuang ke atmosfer. Akan tetapi CO₂ sebenarnya memiliki nilai ekonomis yang tinggi jika dapat dimanfaatkan untuk Enhanced Oil Recovery (EOR). Pada proses injeksi EOR untuk lapangan minyak Y, dibutuhkan CO₂ dengan tingkat kemurnian lebih dari 95 %. Tingkat kemurniaan CO₂ sangat berperan dalam menentukan banyaknya minyak yang yang dapat dipulihkan sedangkan CO₂ dari lapangan gas X hanya memiliki tingkat kemurnian sebesar 76,2 % dengan kandungan air mencapai 16,5 %. Oleh karena itu dibutuhkan proses tambahan untuk dapat menaikkan tingkat kemurnian CO₂. Pressure Swing Adsorption (PSA) dan Triethylene Glycol (TEG) Absorption dapat digunakan untuk menghilangkan kandungan air yang terkandung dalam CO₂. Setelah dimurnikan, CO₂ akan ditransmisikan untuk kemudian digunakan untuk injeksi CO₂ sehingga didapat rancangan fasilitas integrasi CO₂-EOR yang utuh. Berdasarkan hasil analisa ekonomi diperoleh penggunaan PSA pada fasilitas integrasi memiliki nilai NPV sebesar 349.376.372,23 USD, IRR sebesar 19,87 % , dengan biaya investasi sebesar 214.918.114 USD . Sedangkan penggunaan TEG memiliki nilai NPV sebesar 390.869.013,8 USD, IRR sebesar 20,37 %, dan biaya investasi sebesar 240.111.000 USD. Berdasarkan hasil analisis yang telah dilakukan penggunaan PSA dan TEG meskipun memiliki nilai investasi yang besar diperoleh hasil yang paling optimal dari segi net present value (NPV) sebesar 423.392.895,6 USD, Internal return rate (IRR) sebesar 20,71 %, dan payback periode selama 4,06 tahun. Selanjutnya dengan membandingkan skema PSC dan gross split pada penggunaan PSA dan TEG dapat diketahui bahwa gross split lebih optimal dengan nilai NPV sebesar 155 juta USD dan sebesar 19,68 % dibandingkan PSC dengan NPV sebesar 60,53 juta USD dan IRR sebesar 14,32 %. Faktor lain adalah ketahanan terhadap laju produksi minyak dan perubahan harga minyak gross split lebih baik dibanding PSC. Sehingga rancangan fasilitas integrasi CO₂-EOR yang paling layak adalah dengan penggunaan Pressure Swing Adsorption (PSA) dan Triethylene Glycol (TEG) Absorption sebagai unit pemurnian CO₂ dengan mengunakan skema keekonomian gross split.

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The X gas field is a natural gas production field that has a CO₂ product. Due to its corrosive nature and can reduce the selling value of gas, the gas will generally be discharged into the atmosphere. But CO₂ actually has a high economic value if it can be used for Enhanced Oil Recovery (EOR). In the EOR injection process for the Y oil field, CO₂ is needed with a purity of more than 95%. The level of purity of CO₂ plays an important role in determining the amount of oil that can be recovered while CO₂ from the gas field X only has a purity level of 76.2% with a water content reaching 16.5%. Therefore an additional process is needed to be able to increase the CO₂ purity level. Pressure Swing Adsorption (PSA) and Triethylene Glycol (TEG) Absorption can be used to eliminate the water content contained in CO₂. Once purified, CO₂ will be transmitted and then used for CO₂ injection so that a complete design of CO₂-EOR integration facilities is obtained.

Based on the results of economic analysis obtained the use of PSA at the integration facility has an NPV value of 349,376,372.23 USD, an IRR of 19.87%, with an investment cost of 214,918,114 USD. Whereas the use of TEG has an NPV value of 390,869,013.8 USD, an IRR of 20.37%, and an investment cost of 240,111,000 USD. Based on the results of the analysis that has been carried out using PSA and TEG even though having a large investment value, the most optimal results obtained in terms of net present value (NPV) of 423,392,895.6 USD, Internal return rate (IRR) of 20.71%, and payback period of 4.06 years. Furthermore, by comparing the PSC and gross split schemes on the use of PSA and TEG, it can be seen that gross split is more optimal with NPV value of 155 million USD and 19.68% compared to PSC with NPV of 60.53 million USD and IRR of 14.32% . Another factor is the resistance to the rate of oil production and the change in gross split oil prices better than the PSC. So that the most feasible design of CO₂-EOR integration facilities is to use Pressure Swing Adsorption (PSA) and Triethylene Glycol (TEG) Absorption as CO₂ purification units using gross split economic schemes."

"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 volume highlights the latest developments and trends in advanced materials and their properties, the modeling and simulation of non-classical materials and structures, and new technologies for joining materials. It presents the developments of advanced materials and respective tools to characterize and predict the material properties and behavior."

"Dilute Magnetic Semiconductors (DMS) merupakan material yang ideal untuk aplikasi spintronik bahwasanya bukan hanya muatan elektron namun juga spin dari pembawa muatan digunakan untuk proses penyimpanan informasi magnetik. Meskipun telah diketahui bahwa defek berperan penting untuk struktur elektronik dan sifat magnetik DMS, namun pada DMS yang berbasis semikonduktor ZnO, defek mana yang berperan pada kondisi ruang masih diperdebatkan. Skripsi ini menjelaskan interaksi defek yang mungkin terjadi di dalam ZnO didop Cr dan pengaruhnya. Dalam kerangka Density Functional Theory (DFT) kami telah mempelajari struktur elektronik dan sifat magnetik ZnO wurtzite didop dengan Cr, serta dengan keberadaan beberapa varian defek (vakansi oksigen(Vo), impuritas hidrogen(H), dan keduanya(VoH)). Kami menggunakan supersel 2x2x2 untuk mempertahankan konsentrasi dopan Cr rendah (6.25%), pseudopotensial standar Projector Augmented Wave (PAW) untuk menyatakan elektron dekat inti atom maupun elektron valensi, dan pendekatan GGA-PBE untuk energi exchange-correlation yang dikombinasikan dengan pendekatan Hubbard untuk memperhitungkan korelasi elektron yang kuat pada keadaan 3d. Hasil spektrum pita energi, densitas keadaan (DOS), proyeksi densitas keadaan (PDOS), dan distribusi densitas-spin telah diinvestigasi. Hasil investigasi tersebut menunjukkan bahwa keberadaan Vo dalam ZnO:Cr membuat sistem tersebut memiliki keadaan feromagnetik yang lebih stabil daripada ZnO:Cr murni, akibat didapatkan magnetisasi serta densitas keadaan pada level energi Fermi yang lebih tinggi. Keberadaan H dalam ZnO:Cr menyumbang elektron donor pada ZnO:Cr namun hanya terpolarisasi pada daerah pita konduksi sehingga tidak banyak merubah sifat magnetiknya. Dan adapun keberadaan VoH dalam ZnO:Cr ternyata mampu menunjukkan sifat half-metallic. Dengan demikian, dapat dikatakan bahwa untuk memperoleh sifat tertentu dari ZnO didop Cr dapat dilakukan dengan mengatur keberadaan dari ketiga varian defek tersebut.

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Dilute Magnetic Semiconductors (DMS) are ideal materials for applications in spintronics where not only the electron charge but also the spin of the charge carrier is used for information processing. However, the origin of observed interaction in DMS is still a subject of debate. This bachelor thesis put forward an explanation of defect interaction which may occur and the effects within Cr-doped ZnO. Within the framework of Density Functional Theory (DFT) we have studied the electronic and the magnetic properties of wurtzite ZnO doped with transition-metal Cr in the presence of some defects (Vo, H, VoH). We used a 2x2x2 supercell to maintain dilute Cr concentration, the standard Projector Augmented Wave (PAW) pseudopotentials to describe the core electrons and valence electrons, and the exchange-correlation energy of the electrons is treated within the Generalized Gradient Approximation of Perdew, Burke, and Ernzerhof (GGA-PBE) which is combined with a Hubbard approach to include strong electron correlations within the 3d state. The spectrum of band structure, density of states (DOS) and projected density of states (PDOS), and spin-density distribution in this system were investigated. The results of investigation shows that the existence of Vo in ZnO:Cr could stabilize ferromagnetic state of the system, due to the large magnetization and density of states at Fermi level. While, the existence of H introduce donor in ZnO:Cr but just polarized above Fermi level so there is no much change observed in its magnetic properties. And as for the existence of VoH in ZnO:Cr, it turn out able to show the half-metallic properties. Thus, it can be said that we could determine some characteristics of ZnO:Cr by controlling the existence of those defects."

"Dilute Magnetic Semiconductors (DMS) merupakan material yang ideal untuk aplikasi spintronik bahwasanya bukan hanya muatan elektron namun juga spin dari pembawa muatan digunakan untuk proses penyimpanan informasi magnetik. Meskipun telah diketahui bahwa defek berperan penting untuk struktur elektronik dan sifat magnetik DMS, namun pada DMS yang berbasis semikonduktor ZnO, defek mana yang berperan pada kondisi ruang masih diperdebatkan. Skripsi ini menjelaskan interaksi defek yang mungkin terjadi di dalam ZnO didop Cr dan pengaruhnya. Dalam kerangka Density Functional Theory (DFT) kami telah mempelajari struktur elektronik dan sifat magnetik ZnO wurtzite didop dengan Cr, serta dengan keberadaan beberapa varian defek (vakansi oksigen(Vo), impuritas hidrogen(H), dan keduanya(VoH)). Kami menggunakan supersel 2x2x2 untuk mempertahankan konsentrasi dopan Cr rendah (6.25%), pseudopotensial standar Projector Augmented Wave (PAW) untuk menyatakan elektron dekat inti atom maupun elektron valensi, dan pendekatan GGA-PBE untuk energi exchange-correlation yang dikombinasikan dengan pendekatan Hubbard untuk memperhitungkan korelasi elektron yang kuat pada keadaan 3d. Hasil spektrum pita energi, densitas keadaan (DOS), proyeksi densitas keadaan (PDOS), dan distribusi densitas-spin telah diinvestigasi. Hasil investigasi tersebut menunjukkan bahwa keberadaan Vo dalam ZnO:Cr membuat sistem tersebut memiliki keadaan feromagnetik yang lebih stabil daripada ZnO:Cr murni, akibat didapatkan magnetisasi serta densitas keadaan pada level energi Fermi yang lebih tinggi. Keberadaan H dalam ZnO:Cr menyumbang elektron donor pada ZnO:Cr namun hanya terpolarisasi pada daerah pita konduksi sehingga tidak banyak merubah sifat magnetiknya. Dan adapun keberadaan VoH dalam ZnO:Cr ternyata mampu menunjukkan sifat half-metallic. Dengan demikian, dapat dikatakan bahwa untuk memperoleh sifat tertentu dari ZnO didop Cr dapat dilakukan dengan mengatur keberadaan dari ketiga varian defek tersebut.

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Dilute Magnetic Semiconductors (DMS) are ideal materials for applications in spintronics where not only the electron charge but also the spin of the charge carrier is used for information processing. However, the origin of observed interaction in DMS is still a subject of debate. This bachelor thesis put forward an explanation of defect interaction which may occur and the effects within Cr-doped ZnO. Within the framework of Density Functional Theory (DFT) we have studied the electronic and the magnetic properties of wurtzite ZnO doped with transition-metal Cr in the presence of some defects (Vo, H, VoH). We used a 2x2x2 supercell to maintain dilute Cr concentration, the standard Projector Augmented Wave (PAW) pseudopotentials to describe the core electrons and valence electrons, and the exchange-correlation energy of the electrons is treated within the Generalized Gradient Approximation of Perdew, Burke, and Ernzerhof (GGA-PBE) which is combined with a Hubbard approach to include strong electron correlations within the 3d state. The spectrum of band structure, density of states (DOS) and projected density of states (PDOS), and spin-density distribution in this system were investigated. The results of investigation shows that the existence of Vo in ZnO:Cr could stabilize ferromagnetic state of the system, due to the large magnetization and density of states at Fermi level. While, the existence of H introduce donor in ZnO:Cr but just polarized above Fermi level so there is no much change observed in its magnetic properties. And as for the existence of VoH in ZnO:Cr, it turn out able to show the half-metallic properties. Thus, it can be said that we could determine some characteristics of ZnO:Cr by controlling the existence of those defects."