Gas-to-liquid (GTL) process involves the chemical conversion of natural gas (or other gas sources) into synthetic crude that can be upgraded and separated into different useful hydrocarbon fractions including liquid transportation fuels. A leading GTL technology is the Fischer Tropsch process. The objective of this work is to provide a techno-economic analysis of the GTL process and to identify optimization and integration opportunities for cost saving and reduction of energy usage and environmental impact. First, a basecase flowsheet is synthesized to include the key processing steps of the plant. Then, computer-aided process simulation is carried out to determine the key mass and energy flows, performance criteria, and equipment specifications. Next, energy and mass integration studies are performed to address the following items: (a) heating and cooling utilities, (b) combined heat and power (process cogeneration), (c) management of process water, (c) optimization of tail-gas allocation, and (d) recovery of catalystsupporting hydrocarbon solvents. Finally, an economic analysis is undertaken to determine the plant capacity needed to achieve the break-even point and to estimate the return on investment for the base-case study. After integration, 884 million $/yr is saved from heat integration, 246 million $/yr from heat cogeneration, and 22 million $/yr from water management. Based on 128,000 barrels per day (BPD) of products, at least 68,000 BPD capacity is needed to keep the process profitable, with the return on investment (ROI) of 5.1%. Compared to 8 $/1000 SCF natural gas, 5 $/1000 SCF price can increase the ROI to 16.2%.

Chemnitz, Techn. Univ., Diss., 1997.

Berlin, Humboldt-Univ., Diss., 2002. / Computerdatei im Fernzugriff.

Berlin, Humboldt-Univ., Diss., 2002. / Computerdatei im Fernzugriff.

München, Techn. University, Diss., 2005.

München, Techn. Universiẗat, Diss., 2004.

Berlin, Humboldt-Universiẗat, Diss., 2002.

This study addresses the issue of overseas news production of foreign news media when they enter the market of the Mainland China. By making an in-depth investigation of BBC’s and the FT’s operations in China and comparing the news texts of the two news media’s Chinese online portals with that of their British online portals, differences in terms of narratives, semantics, plot emphasis, and ideologies are identified and analysed, thus revealing the cross-cultural behaviour patterns of the two prominent British news media in terms of balancing between British journalistic ideology and Chinese regulations, western journalistic style and Chinese readers’ tastes, and between moral standards and commercial profit. The four online portals are compared through three Chinese news events that took place in the year 2012: the downfall of Chinese high ranking official Bo Xilai; the large-scale anti-Japan protests in the summer of 2012; and Chinese writer Mo Yan winning the Nobel Prize for Literature. The three news events covered the fields of politics, economy, society and culture. The investigating methods include quantitative analysis and framing analysis of the news reports on the three news events produced by the four online portals, translation study of the translated news reports of the four online portals and semi-structured interviews with journalists and editors of BBC Chinese and the FT. The central argument is that BBC and the FT act differently in China and in the UK so as to cater to local media markets on many aspects including journalistic practice, coverage of local news, and media policy. Such changes in some cases do not remain consistent with their claims to represent the same news media. Consequently, the Chinese branches of the two prominent British news media become neither a British journalistic ideology carrier nor a copycat of a Chinese native news producer but rather a mixture of both cultures.

No / Cocrystal monohydrate of nitrofurantoin (NF) with melamine (MELA) has been studied as NF is an antibacterial drug used for the treatment of urinary tract infections. The structure of nitrofurantoin-melamine-monohydrate (NF-MELA-H2O) is characterized by FT-IR and FT-Raman spectroscopy. The energies and vibrational frequencies of the optimized structures calculated using quantum chemical calculations. Supported by normal coordinate analyses and potential energy distributions (PEDs), the complete vibrational assignments recommended for the observed fundamentals of cocrystal hydrate. With the aim of inclusion of all the H-bond interactions, dimer of NF-MELA-H2O has been studied as only two molecules of cocrystal hydrate are present in the unit cell. By the study of dimeric model consistent assignment of the FT-IR and FT-Raman spectrum obtained. H-bonds are of essential importance in an extensive range of molecular sciences. The vibrational analyses depict existence of H-bonding (O-H⋯N) between water O-H and pyridyl N atom of MELA in both monomer and dimer. To probe the strength and nature of H-bonding in monomer and dimer, topological parameters such as electron density (ρBCP), Laplacian of electron density (∇2ρBCP), total electron energy density (HBCP) and H-bond energy (EHB) at bond critical points (BCP) are evaluated by quantum theory of atoms in molecules (QTAIM). Natural bond orbitals (NBOs) analyses are carried out to study especially the intra and intermolecular H-bonding and their second order stabilization energy (E(2)). The value of HOMO-LUMO energy band gap for NF-MELA-H2O (monomer and dimer both) is less than NF, showing more chemical reactivity for NF-MELA-H2O. Chemical reactivity has been described with the assistance of electronic descriptors. Global electrophilicity index (ω = 7.3992 eV) shows that NF-MELA-H2O behaves as a strong electrophile than NF. The local reactivity descriptors analyses such as Fukui functions, local softnesses and electrophilicity indices performed to determine the reactive sites within NF-MELA-H2O. In MEP map of NF-MELA (monomer and dimer) electronegative regions are about NO2 and C=O group of NF, although the electropositive regions are around NH2, N-H group and H2O molecule. Molar refractivity (MR) value of NF-MELA-H2O (monomer and dimer) lies within the range set by Lipinski's modified rules. This study could set as an example to study the H-bond interactions in pharmaceutical cocrystals.

Submitted by Gizele Lima (gizele.lima@inpa.gov.br) on 2017-08-07T14:59:16Z No. of bitstreams: 2 Dissertação_mestrado_Carla Lang.pdf: 1090969 bytes, checksum: 1a54204915e84b680485beadcfce6175 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-08-07T14:59:16Z (GMT). No. of bitstreams: 2 Dissertação_mestrado_Carla Lang.pdf: 1090969 bytes, checksum: 1a54204915e84b680485beadcfce6175 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2014-05-21 / Amazon species identification in different ontogenetic stages by near infrared spectroscopy Precise identification of species requires high level of knowledge by taxonomists and presence of reproductive material. This represents a major limitation for those working with seedlings and juveniles, which differ morphologically from adults and do not bear reproductive structures. Near-infrared spectroscopy (FT-NIR) was previously shown to be effective in species discrimination of adult plants, so if young and adults have the same spectral signature, discriminant functions based on FT-NIR spectra of adults can be used to identify young. We tested this with a sample of 419 plants in 16 species within Protium and Crepidospermum (Burseraceae). We obtained 12 spectral readings per leaf, from adaxial and abaxial surfaces of dried leaves and compared the rate of correct predictions of species with discriminant functions for different combinations of readings. We obtained an average, over all species, of 75% correct identifications of young plants by discriminant equations developed based only on adults, when the most informative wavelengths were selected. Most species were well predicted (75-100% correct identifications) and only three had poor predictions (27-60%). This occurred despite of the spectra of young individuals being distinct of those of adults when species were analyzed individually. When young and adults individuals are included in the same discriminant function, correct predictions of external samples attained 99%. Some of the poorly predicted species were re-evaluated by an expert in the family in a blind procedure and proven to be a mixture of samples in different species. Even considering some limitations, concluded that FT-NIR has a high potential in identification of species even in different ontogenetic stages. Key words: Burseraceae, leaves, species discrimination, FT-NIR, ontogenetic stages / A identificação das espécies de plantas exige um alto nível de conhecimento de taxonomistas e a presença de material reprodutivo. Isso representa uma das grandes limitações para quem trabalha com plântulas e juvenis, os quais diferem morfologicamente dos adultos e ainda não apresentam estruturas reprodutivas. Estudos prévios demonstraram que a espectroscopia do infravermelho próximo (FT-NIR) é eficaz na discriminação de espécies de plantas em estádio adulto, logo se indivíduos jovens e adultos possuirem uma assinatura espectral semelhante, funções discriminantes baseadas em leituras espectrais de indivíduos adultos poderiam ser usadas para identificar plântulas e juvenis. Testamos isto com uma amostra de 429 espécimes de 16 espécies dentre os gêneros Protium e Crepidospermum (Burseraceae). Para isso coletamos 12 leituras espectrais, abaxial e adaxial, de folhas secas e comparamos as taxas de predições corretas das espécies para diferentes conjuntos de dados e modelos discriminantes. Obtivemos uma média, sobre todas as espécies, de 75% de acertos nas identificações dos jovens quando as funções discriminantes foram construídas com base nos adultos e com a seleção dos comprimentos de onda mais informativos. A maior parte das espécies foi bem predita (75-100% de identificações corretas) e apenas três espécies tiveram baixas predições (27-60%). Isso ocorreu devido os espectros dos jovens serem distintos dos espectros dos adultos quando as espécies foram analisadas individualmente. Quando jovens e adultos foram incluídos na função discriminante, amostras externas foram preditas corretamente, alcançando 99% de acerto. Algumas das espécies mal preditas foram novamente avaliadas por um perito da família por um procedimento cego e comprovou-se uma mistura de amostras de diferentes espécies. Mesmo considerando algumas limitações, concluimos que a FT-NIR tem um elevado potencial na identificação de espécies, mesmo em diferentes estádios ontogenéticos. Palavras chave: Burseraceae, folhas, discriminação de espécies, FT-NIR, fases ontogenéticas