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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Penzion / Guesthouse

Havranová, Veronika January 2017 (has links)
This thesis deals with the project documentation of the accommodation facility.Guest house kapacity is 26 beds and 32 seated restaurant. The object is designed as a threefloor. In the first floor is located main entrance, reception desk and restaurant with facilities and wellness.In the sekond and thirt floor are rooms for guests and five other beds for a staffs. On second floor has been situated room for invalids also. The building is walled with saddle roof. The project was processed by a computer program ArchiCAD.
92

A systems chemistry approach to understanding cucurbit[7]uril-guest dynamics

Vos, Kevin Andrew 05 June 2020 (has links)
Systems chemistry is an emerging field of chemistry that studies complex mixtures of molecules that give rise to emergent properties that are not always predictable when studying the components of the mixtures in isolation. A systems chemistry approach has been adopted in fields such as self-assembly and self-sorting, where the dynamic recognition of complementary binding motifs to organize molecules is the central focus. Supramolecular systems are assembled through reversible, non-covalent interactions. The reversibility of supramolecular systems makes them dynamic. Understanding the dynamic nature of complex systems will allow for a bottom-up approach to the rational design of complex mixtures, such as kinetically trapped self-sorting systems. The first objective of this work was to understand the effects the identity and concentration of biologically relevant metal cations have on a the mechanism of binding and rate of kinetics of a cucurbit[7]uril (CB[7])-guest complex. Metal cations are frequently added to cucurbit[n]uril (CB[n]) systems. While metal cations are known to decrease the overall equilibrium constant of a CB[n]-guest complex, there has not been much consideration about how different metal cations can affect the CB[n]-guest binding mechanism beyond introducing competitive equilibria. Kinetic studies of the interactions between CB[7] and 1-(2-naphthyl)-ethylammonium (NpH+) in the presence of Ca2+ and Na+ were investigated. It was found that the binding mechanism between NpH+ and CB[7] was the formation of an exclusion complex and an inclusion complex. An exclusion complex is the formation of a complex where the cationic ammonium group of the guest associates to the carbonyl lined portals of CB[7], while the aromatic group remains exposed to the surrounding; while an inclusion complex is formed when the aromatic group of the guest enters the hydrophobic cavity of CB[7]. By increasing the metal cation concentrations, the exclusion complex was seen to disappear from the overall kinetics. When Ca2+ cations were used instead of Na+ cations, a Ca2+ cation capped inclusion complex was formed. The Ca2+ cation capped inclusion complex was found to have a lower dissociation rate constant than the uncapped complex between NpH+ and CB[7]. The second objective of this work was to understand how the structure of guest molecules effected the kinetic time scale of reaction with CB[7]. The kinetics between CB[7] and three different aromatic dications were measured to understand the structural features that influence the change in kinetic time scales: methyl viologen (MV2+), benzidine (Bn2+) and 2,7’-dimethyl-diazapyrenium (MDAP2+). It was found that moving the cationic charges further apart slowed down the kinetics from the sub millisecond time scale (MV2+) to the millisecond time scale (Bn2+); further, it was found that adding rigidity and width to the molecule (MDAP2+) slowed down the kinetics onto the minute time scale. The final objective of this work was to use the understanding of complexity gained in the metal cation project and the guest design for kinetic time scales project to rationally design a kinetically-trapped self-sorting system. The equilibrium constants and time scale of kinetics between a ditopic guest molecule and three host molecules (CB[6], CB[7] and β-CD) were determined to investigate the feasibility of the kinetically-trapped self-sorting system. Due to the complexity introduced by metal cations discovered earlier, β-cyclodextrin (β-CD) was used to modulate the concentration of guest that could be bound by CB[n]s. As a concentration modulator the requirements of β-CD were that the kinetics must be faster than the millisecond time scale and the equilibrium constant with the guest must be much lower than the equilibrium constants between the guest and CB[n]s. CB[6] was proposed as a thermodynamic sink due to its slow kinetics for complex formation with benzyl ammonium. The requirements for the guest complexation with CB[6] were that the kinetics had to be on the minute to hour time scale and the equilibrium constant with the guest had to be the highest of the three host molecules. CB[7] was chosen as the kinetic trap of the self-sorting system. The requirements for the CB[7] complex were that the kinetics had to be on the millisecond to second time scale and the equilibrium constant needed to be lower than the equilibrium constant of the guest@CB[6] complex, but higher than the guest@β-CD complex. The kinetic and thermodynamic requirements between the guest molecule and CB[7], and between the guest molecule and β-CD were met. The kinetics between CB[6] and the guest molecule were on the hour time scale, meaning the kinetic requirement was met, however, the equilibrium constant was found to be lower than the equilibrium constant between the guest molecule and CB[7]. The results in this work showed that the rational design of kinetically-trapping self-sorting systems is possible, but some modifications to the structure of the guest molecule is required to make this self-sorting system work. / Graduate / 2021-06-05
93

Adsorption and Diffusion Phenomena in Crystal Size Engineered ZIF‑8 MOF

Tanaka, Shunsuke, Fujita, Kosuke, Miyake, Yoshikazu, Miyamoto, Manabu, Hasegawa, Yasuhisa, Makino, Takashi, Van der Perre, Stijn, Cousin Saint Remi, Julien, Van Assche, Tom, Baron, Gino V., Denayer, Joeri F. M. 18 September 2018 (has links)
ZIF-8 is a flexible zeolitic imidazole-based metal−organic framework whose narrow pore apertures swing open by reorientation of imidazolate linkers and expand when probed with guest molecules. This work reports on the crystal size dependency of both structural transitions induced by N2 and Ar adsorption and dynamic adsorption behavior of n-butanol using well-engineered ZIF-8 crystals with identical surface area and micropore volume. It is found that the crystal downsizing of ZIF-8 regulates the structural flexibility in equilibrium adsorption and desorption of N2 and Ar. Adsorption kinetics of n-butanol in ZIF-8 are strongly affected by the crystal size, however, not according to a classical intracrystalline diffusion mechanism. Our results suggest that structural transitions and transport properties are dominated by crystal surface effects. Crystal downsizing increases the importance of such surface barriers.
94

Structures, Stabilities and Electronic Properties of Endo- and Exohedral Dodecahedral Silsesquioxane (T <sub>12</sub>-POSS) Nanosized Complexes with Atomic and Ionic Species

Hossain, Delwar, Hagelberg, Frank, Saebo, Svein, Pittman, Charles U. 04 May 2010 (has links)
The structures of endohedral complexes of the polyhedral oligomeric silsesquioxane (POSS) cage molecule (HSiO 3/2) 12, with both D 2d and D 6h starting cage symmetries, containing the atomic or ionic species: Li 0, Li +, Li -, Na 0, Na +, Na -, K 0, K +, K -, F -, Cl -, Br -, He, Ne, Ar were optimized by density functional theory using B3LYP and the 6-311G(d,p) and 6-311 ++G(2d,2p) basis sets. The exohedral Li +, Na +, K +, K -, F -, Cl -, Br -, He, Ne, Ar complexes, were also optimized. The properties of these complexes depend on the nature of the species encapsulated in, or bound to, the (HSiO 3/2) 12 cage. Noble gas (He, Ne and Ar) encapsulation in (HSiO 3/2) 12 has almost no effect on the cage geometry. Alkali metal cation encapsulation, in contrast, exhibits attractive interactions with cage oxygen atoms, leading to cage shrinkage. Halide ion encapsulation expands the cage. The endohedral X@(HSiO 3/2) 12 (X = Li +, Na +, K +, F -, Cl -, Br -, He and Ne) complexes form exothermically from the isolated species. The very low ionization potentials of endohedral Li 0, Na 0, K 0 complexes suggest that they behave like "superalkalis". Several endohedral complexes with small guests appear to be viable synthetic targets. The D 2d symmetry of the empty cage was the minimum energy structure in accord with experiment. An exohedral fluoride penetrates the D 6h cage to form the endohedral complex without a barrier.
95

Synthesis, Characterization and Host-Guest Complexation Studies of Dendritic and Linear Pyridinium Derivatives

Murugavel, Kathiresan 20 December 2010 (has links)
Convergent and divergent strategies for the synthesis of viologen dendrimers with 1,3,5-tri-methylene branching units are presented. The synthesis of 3,5-bis(hydroxymethyl) benzyl bromide was optimized. The analysis of the crystal structure of 1-[3,5-bis(hydroxymethyl)benzyl]-4-(pyridin-4-yl) pyridinium hexafluorophosphate together with PM3 calculations opens an avenue to judge the structure and conformation of benzylic viologen dendrimers. In order to study chemical trigger induced conformational changes, viologen dendrimers were spin-labeled via a divergent approach. 1-(2,4-dinitrophenyl)-4-(pyridin-4-yl)pyridinium hexafluorophosphate was used as the end group to yield an activated dendrimer of the respective generation. The corresponding dendrimers were spin-labeled by reacting the active functionality with 4-amino TEMPO. The products were characterized by ESR (spin-label efficiency) and conventional cyclic voltammetry. Dynamic ESR studies are planned. New trimethylene-dipyridinium dendrimers were synthesized via a divergent approach using 4-tert-butylbenzyl group as the peripheral group. These dendrimers are well soluble in DMF or DMSO as PF6 salts and they act as a host for anthraquinone-2,6-disulfonate (AQDS). They can be stoichiometrically titrated with AQDS as shown by 1H-NMR, DOSY and cyclic voltammetry. Upon loading them with AQDS, the dendrimers undergo first a contraction, they reach a minimum hydrodynamic radius for complete charge compensation and they re-open when overcharging takes place. The contraction is supported by MM+ calculations. Upon stepwise loading of G2 (42 positive charges) with AQDS (2 negative charges), the first 3 molar equivalents (6 neg. charges) occupy the innermost dendrimer shell (consisting of 6 pos. charges), the next 6 equivalents (12 neg. charges) occupy the middle shell (12 pos. charges) and the last 12 equivalents AQDS (24 neg. charges) occupy the outermost shell of the dendrimer (24 pos. charges), as supported by 1H-NMR titrations yielding the magic equivalent numbers of 3, 9=3+6, and 21=3+6+12. Such stepwise radial complexations again in DMSO were further demonstrated using other molecular guests (mono-, di- and trianionic) as well as with on purpose synthesized viologen dendrimers. α,ω-dibromoalkanes were bifunctionalized in two steps to yield alkyl phosphonates with pyridinium, trimethylenedipyridinium, bipyridinium or a sulfonate at their ω end. These compounds were used as surface modifiers to build biomimetic membranes on the pore walls of mesoporous TiO2. Host-guest interaction studies with on purpose synthesized viologen compounds have been performed in collaboration.
96

Penzion Zátoka / Guesthouse Zátoka

Rajchl, Filip Unknown Date (has links)
The aim of my thesis is to design new Guest house called Zátoka near the Pozlovice dam. Thesis is divided in three parts. First is part is focused on building design and construction. Second part is focused on HVAC design and renewable energy sources. Third part is focused on advanced application of BIM in building design. Guest house is two – storey building but there is one more underground storey for sport activities which is not part of the building service, but it is part of the design. Ground floor contains three guest rooms, office, utility room and air condition room and of course wind lobby and entrance hall with stairs. In the second floor we can find four guest rooms and corridor. Heating in the building is secured by pellet boiler with storage reservoir. Ventilation is provided by two air condition units. And cooling is secured by one cooling unit on the roof. Each room has radiators and cooling distribution units and ventilation. On the roof we can find 26 photovoltaic panels. Third part is focused on digital model of the building. Each part of the model contains information and whole model is one big database of information about the building which can be used through the whole life cycle of the building.
97

Studies on Relationship between Layer Structures and Functions in Hofmann-type Coordination Polymers / ホフマン型配位高分子の層構造と機能の相関に関する研究

Ohtani, Ryo 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18234号 / 工博第3826号 / 新制||工||1586(附属図書館) / 31092 / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 北川 進, 教授 松田 建児, 教授 濵地 格 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
98

Studies on Synthesis and Host-Guest Chemistry of Cycloparaphenylenes / シクロパラフェニレンの合成法とホストゲスト化学に関する研究

Iwamoto, Takahiro 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18298号 / 工博第3890号 / 新制||工||1597(附属図書館) / 31156 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 山子 茂, 教授 中條 善樹, 教授 村田 靖次郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
99

Synthesis and Properties of P-Stereogenic Cyclic Phosphines / 不斉リン原子を有する光学活性環状ホスフィンの合成と性質

Kato, Ryosuke 23 March 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19744号 / 工博第4199号 / 新制||工||1648(附属図書館) / 32780 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 中條 善樹, 教授 赤木 和夫, 教授 松原 誠二郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
100

The design, synthesis and evaluation of synthetic transcription factors (Syn-TFs) / 人工転写因子Syn-TFsのデザイン、合成、及び評価に関する研究 / # ja-Kana

Yu, Zutao 25 September 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第21332号 / 理博第4428号 / 新制||理||1636(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)教授 杉山 弘, 教授 秋山 芳展, 准教授 竹田 一旗 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

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