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Convenient Debonding Strength Evaluation for Spray Coating Based on Intensity of Singular Stress
No full textHearth rolls are used in continuous annealing furnace to produce thin steel sheet. The roll surface is usually coated by using thermal spraying, which has high adhesive strength and wears resistance. However, in the ceramics coating, thermal stress caused during heating and cooling process in the furnace may lead to debonding due to the low toughness of ceramics. In order to improve the heat resistance of the thermally sprayed coating, it is essential to evaluate the debonding strength. Generally, heat resistance of thermal spray coating is evaluated by thermal shock test prescribed by JIS H8304 although few research is available in terms of singular stress at the end of the interface for JIS specimen under thermal shock. This paper focuses on the intensity of the singular stress at the end of interface. Then, the most suitable conditions are discussed with varying the coating material and the coating thickness
コバルト電解液を用いた透明導電膜を必要としないバックコンタクト色素増感太陽電池
No full text九州工業大学博士学位論文 学位記番号:生工博甲第245号 学位授与年月日:平成27年9月25日1. Introduction||2. Measurement procedures and methods||3. Transparent conductive oxide-less (TCO-less) back contact (BC) dye-sensitized solar cells based on cobalt electrolyte employing organic Indoline D-205 dye||4. Transparent conductive oxide-less back contact dye-sensitized solar cells using Zinc porphyrin dye employing cobalt complex redox shuttle||5. TCO-less DSSCs based on cobalt electrolyte employing nanoporous TiO2 film used as an electrolyte absorbing layerThe central theme of this thesis moves around the technical overview regarding the two bottlenecks
of dye-sensitized solar cells such as removal of costly TCO components by employing flexible
stainless steel metal mesh to pave the way towards low-cost DSSCs. At the same time, utilization
of cobalt complex based redox shuttle to incorporate merits like weak visible light absorption, less
corrosive nature to the metallic grid and more positive redox potential to produce higher opencircuit
potential as compared to the most commonly employed iodine based electrolyte in TCOless
back contact DSSCs. Attempts have been made to understand the limiting factors and to search
for their amicable solutions towards enhancing the overall photoconversion efficiency in such
TCO-less DSSCs utilizing cobalt electrolyte.
TCO-less back contact dye-sensitized solar cells were conveniently fabricated using
nanoporous TiO2 layer (particle size 15-20 nm) screen-printed onto the stainless steel metal mesh
and adsorbed with D-205 dye used as flexible photoanode based on cobalt based redox shuttle.
Surface protection of the metal mesh was found to be highly beneficial to suppress the back
electron transfer from the bare metal mesh to the oxidized species of cobalt redox electrolyte.
Protection of metal mesh by a thin layer of Ti metal (sputtered) acting as charge recombination
blocking layer led to the enhancement in the photoconversion efficiency of TCO-less back contact
DSSC from 0.66% to 3.33%, which was little a less than that of the conventional DSSC consisting
of TCO glasses (4.02%). Co-sensitization of D-205 dye with D-131 dye provided even further
increase in the photoconversion efficiency to 3.59% because of their complementary photon
harvesting properties in the region from 400-500 nm.
In order to enhance the photoconversion efficiency even further, TCO-less back contact
DSSCs using nanoporous TiO2 layer having comparatively larger particle size of 30 nm expediting
the mass transport of the [Co(bpy)3]2+/3+ species in combination with porphyrin sensitizer coded
with YD2-o-C8 having magnificent photon harvesting over the whole visible region was also
investigated. In this case, protection of metal mesh by a thin layer of Ti (sputtered) led to
enhancement in the photoconversion efficiency to 4.53% as compared to the unprotected one
(3.12%). Increasing the pore size of porous polymer PTFE film from 0.1 μm to 0.2 μm led to the
further increase in the photoconversion efficiency to 4.89%. Moreover, Co-sensitization of YD2-
o-C8 dye with Y123 organic sensitizer led to the further enhancement in the photoconversion
efficiency up to 5.25% along with the impressive open-circuit voltage of 0.88 V.
Finally, to enhance the photoconversion efficiency even further by enhancing the diffusion
of [Co(bpy)3]2+/3+ species, TCO-less back contact DSSCs have been fabricated using
comparatively thinner nanoporous TiO2 layer (5.5 μm) employed as an electrolyte absorbing layer
coated onto to the Pt counter electrode. This modification was implemented as a replacement for
the thick porous polymer PTFE film (35 μm). Protection of bare TiO2 layer (5.5 μm) used as an
electrolyte absorbing layer with YD2-o-C8 dye retards the electrostatic binding very effectively
between the negatively charged TiO2 surface and the positively charged Co3+ species owing to
their long alkyl chain and provides the facile diffusion of the Co3+ species through the nanoporous
TiO2 layer providing the best photoconversion efficiency of 6.42%
Particle Simulation on Epidermal Skin Formation - Mechanism of Basal Layer Formation -
Get PDFThe 6th TSME International Conference on Mechanical Engineering, 16-18 December 2015, the Regent Cha-am beach Resort, Hua-Hin, Thailand.Skin is the largest organ of the human body. The bottom of the epidermis is called the basal layer and is very uneven. However, the mechanism of uneven formation of the basal layer has not yet been elucidated. Computational simulation can be useful in further understanding the mechanisms of skin formation. We propose a particle model that can handle complex biological phenomena, including cell interactions and is a suitable method for the simulation of skin formation. In this study, we created a model similar to the actual skin using three-dimensional analysis and elucidated the formation mechanism of the basal layer. Particularly, each basal cell of this model is subjected to three patterns of cell division, which can simulate skin formation with an increase and decrease of basal cells and the consequent generation of upper cell layers. Therefore, we analyzed the association between these cell division patterns and the uneven formation of the cell layer
In vitro apatite formation and visible-light photocatalytic activity of Ti metal subjected to chemical and thermal treatments
Get PDFIn this study, we investigated the surface structure, apatite formation in simulated body fluid (SBF), and visible-light photocatalytic activity of Ti metal subjected to chemical and thermal treatments. Ti metal samples treated with NaOH, a nitrogen-containing solution (0.1 M HNO3, 0.1–1.0 M (H2N)2Cdouble bond; length as m-dashO, or 0.1–1.0 M NH4Cl), and heat showed apatite formation on their surfaces in SBF, whereas those treated with NaOH, 0.5 or 1.0 M HNO3, and heat did not. In the former case, apatite formation may be attributable to the fine network structure of anatase-type TiO2 doped with a small amount of nitrogen on the surface of the Ti metal. The Ti metal treated with the latter treatment showed higher methylene blue decomposition than the untreated sample and the one treated with the former treatment. This preliminary result suggests that Ti metal treated with NaOH, 0.1 M HNO3, and heat can potentially show visible-light-induced antibacterial property as well as bone-bonding ability
半導体パルスレーザー照射による神経細胞の機能破壊に関する研究 －てんかん外科手術の新手法提案に向けて－
Get PDF九州工業大学博士学位論文（要旨） 学位記番号:生工博甲第226号 学位授与年月日:平成26年9月26
Development of high-ZT organic -inorganic hybrid materials
No full text九州工業大学博士学位論文 学位記番号:工博甲第359号 学位授与年月日:平成26年3月25日第1章 序論||第2章 耐熱性ユニットを有するブロックコポリマーを用いたポーラス構造体の作製||第3章 ミクロポーラス構造を有するテンプレートフィルムを用いたフレキシブル熱電変換モジュールの作製||第4章 印刷法を用いた導電性ポリマーを有するビスマステルル熱電薄膜の作製||第5章 耐熱性樹脂とイオン液体を用いた高性能塗布型熱電変換素子の作製||第6章 結
UKF によるセルフセンシング磁気浮上系の磁気飽和に対する補償
Get PDF九州工業大学博士学位論文 学位記番号:工博甲第384号 学位授与年月日:平成27年3月25日1 序論||2 原理||3 実験装置||4 磁気飽和の影響||5 検出範囲を限定した磁気飽和に対するセルフセンシング制御法||6 UKF を用いた磁気飽和に対するセルフセンシング制御法||7 結
ステンレス溶射皮膜の溶融酸化物による浸透処理に関する研究
No full text九州工業大学博士学位論文 学位記番号:生工博甲第230号 学位授与年月日:平成27年3月25日1. Introduction||2. Literature Review||3. Experimental||4. Wettability of SUS316L Stainless Steel by Molten SiO2-Al2O3-K2O-Na2O Oxides|| 5. Wettability of SUS316L Stainless Steel by Molten MnO-SiO2 Oxides|| 6. Penetration Treatments of Stainless Steel Coating by SiO2-Al2O3-K2O-Na2O Oxides||7. Penetration Treatments of Stainless Steel Coating by MnO-SiO2 Oxides||8. Conclusio
アブラヤシ葉柄の糖類とバイオエタノールへの変換
Get PDF九州工業大学博士学位論文 学位記番号:生工博甲第224号 学位授与年月日:平成26年9月26日CHAPTER 1 Introduction and Literature Review||CHAPTER 2 Investigation of Oil Parm Frond Properties for use as Biomaterials and Bioenergy||CHAPTER 3 Superheated Steam as an Appropriate Pretreatment to Improve Fermentable Biosugars Yield from Oil Parm Frond Petiole Residue||CHAPTER 4 Bioethanol from Oil Parm Frond Petiole Induced by Natural Micronutrients from Petiole's Juice||CHAPTER 5 Concluding Remarks and Suggestions for Future Research||ReferencesPalm oil industry is one of the Malaysian top commodities, producing abundant of lignocellulosic biomass as waste. Although a lot of studies have been done for these biomass, oil palm frond (OPF) has been neglected due to the current good agricultural practise, where it is required to be left in the oil palm plantation for nutrient recycling. However, a recent finding showed that the petiole parts of the OPF is rich in sugars, which can be extracted by pressing the petiole. As for the petiole biomass after pressing, it require pretreatment to allow enzymatic hydrolysis to take place smoothly. In the first chapter, a literature studies was carried out to understand the gap in the research for OPF, while trying to relate it with excessive energy of palm oil industry. OPF from the oil palm plantation involves a volume of 83 million tons in Malaysia alone. As it was suggested earlier that the petiole alone is a good source for sugars, its utilization is restricted due to the good agricultural practise. Therefore, the second chapter discuss the comparison of oil palm biomass volume to justify the reason of OPF selection. Detailed composition of the OPF components was also studied to understand which parts of the fronds actually contribute to the nutrient recycling, as well as to suggest whether it is safe or not to take the petiole out of the plantation. Amongst the four components, namely petiole, stem, rachis and leaflet, we found that the main contributor for the nutrient recycling by OPF is actually the leaflet, while the petiole has only a little effect. We also suggest that the logistic issues regarding the transportation of the OPF petiole from the plantation to the palm oil mill, can be solved by adding extra cart behind the existing truck. Therefore we do not need extra truck and driver. Third chapter is mainly about the pretreatment and cellulose hydrolysis of the petiole residue. We suggest that reuse of the oil palm steam (superheated steam, SHS) for pretreatment of petiole residue will be beneficial and profitable for the palm oil mill. The use of SHS is found to be superior as compared to a wet disc milling (WDM) in term of pretreatment duration and practicality in the palm oil mill. Upon treating the pressed petiole, we found that pretreatment of petiole at 180°C for 10 minutes yielded the highest sugars yield amongst the range of the treatment, which was achieved by using a low 10 FPU cellulase activity. This resulted in improvement of specific biosugars yield by 79.91% from untreated petiole residue. This short time pretreatment improvement is mainly due to the changes in specific surface area, particle size and properties of lignocellulose components which are discussed in detail throughout this study. We also suggest that pretreatment time also affected by residual oil such as found in oil palm empty fruit bunches (OPEFB) and oil palm mesocarp fibre (OPMF), therefore the petiole has advantage for not containing the oil residue. In the fourth chapter, we study the effect of replacing the commercial nutrients for yeast by petiole’s juice in bioethanol fermentation. This is due to a parallel study’s finding which shows that the juice is rich in nutrients and some vitamins, which can support the yeast fermentation. Usage of petiole’s juice to replace commercial nutrients in bioethanol production may reduce the production cost. We found that there was no significant difference in the fermentation performance when we replaced commercial medium with petiole juice. This concludes that the petiole juice is suitable as a supplement for bioethanol fermentation of OPF petiole hydrolysate