Development of optical fiber sensors for selected chemical and physical sensing applications

The objective of the preset work is to develop optical fiber sensors for various physical and chemical parameters. As a part of this we initially investigated trace analysis of silica, ammonia, iron and phosphate in water. For this purpose the author has implemented a dual wavelength probing scheme which has many advantages over conventional evanescent wave sensors. Dual wavelength probing makes the design more reliable and repeatable and this design makes the sensor employable for concentration, chemical content, adulteration level, monitoring and control in industries or any such needy environments. Use of low cost components makes the system cost effective and simple. The Dual wavelength probing scheme is employed for the trace analysis of silica, iron, phosphate, and ammonia in water. Such sensors can be employed for the steam and water quality analysers in power plants. Few samples from a power plant are collected and checked the performance of developed system for practical applications.

Synthesis, Characterization and Catalytic Activity of Nanocrystalline Ceria Modified With Zirconia

The use of catalysts in chemical and refining processes has increased rapidly since 1945, when oil began to replace coal as the most important industrial raw material. Catalysis has a major impact on the quality of human life as well as economic development. The demand for catalysts is still increasing since catalysis is looked up as a solution to eliminate or replace polluting processes. Metal oxides represent one of the most important and widely employed classes of solid catalysts. Much effort has been spent in the preparation, characterization and application of metal oxides. Recently, great interest has been devoted to the cerium dioxide (CeO2) containing materials due to their broad range of applications in various fields, ranging from catalysis to ceramics, fuel cell technologies, gas sensors, solid state electrolytes, ceramic biomaterials, etc., in addition to the classical application of CeO2 as an additive in the so-called three way catalysts (TWC) for automotive exhaust treatment. Moreover, it can promote water gas shift and steam reforming reactions, favours catalytic activity at the interfacial metal-support sites. The solid solutions of ceria with Group IV transitional-metals deserve particular attention for their applicability in various technologically important catalytic processes. Mesoporous CeO2−ZrO2 solid solutions have been reported to be employed in various reactions which include CO oxidation, soot oxidation, water-gas shift reaction, and so on. Inspired by the unique and promising characteristics of ceria based mixed oxides and solid solutions for various applications, we have selected ceria-zirconia oxides for our studies. The focus of the work is the synthesis and investigation of the structural and catalytic properties of modified and pure ceria-zirconia mixed oxide.

Die Privatisierung der Öffentlichen Personennahverkehrs (ÖPNV) und die damit verbundene Problematik des marktwirtschaftlichen und interventionistischen Dualismus am Beispiel des Schienenpersonennahverkehrs (SPNV) in der Fläche

Der SPNV als Bestandteil des ÖPNV bildet einen integralen Bestandteil der öffentlichen Daseinsvorsorge. Insbesondere Flächenregionen abseits urbaner Ballungszentren erhalten durch den SPNV sowohl ökonomisch als auch soziokulturell wichtige Impulse, so dass die Zukunftsfähigkeit dieser Verkehrsart durch geeignete Gestaltungsmaßnahmen zu sichern ist. ZIELE: Die Arbeit verfolgte das Ziel, derartige Gestaltungsmaßnahmen sowohl grundlagentheoretisch herzuleiten als auch in ihrer konkreten Ausformung für die verkehrswirtschaftliche Praxis zu beschreiben. Abgezielt wurde insofern auf strukturelle Konzepte als auch praktische Einzelmaßnahmen. Der Schwerpunkt der Analyse erstreckte sich dabei auf Deutschland, wobei jedoch auch verkehrsbezogene Privatisierungserfahrungen aus anderen europäischen Staaten und den USA berücksichtigt wurden. METHODEN: Ausgewertet wurden deutschsprachige als auch internationale Literatur primär verkehrswissenschaftlicher Ausrichtung sowie Fallbeispiele verkehrswirtschaftlicher Privatisierung. Darüber hinaus wurden Entscheidungsträger der Deutschen Bahn (DB) und DB-externe Eisenbahnexperten interviewt. Eine Gruppe 5 DB-interner und 5 DB-externer Probanden nahm zusätzlich an einer standardisierten Erhebung zur Einschätzung struktureller und spezifischer Gestaltungsmaßnahmen für den SPNV teil. ERGEBNISSE: In struktureller Hinsicht ist die Eigentums- und Verfügungsregelung für das gesamte deutsche Bahnwesen und den SPNV kritisch zu bewerten, da der dominante Eisenbahninfrastrukturbetreiber (EIU) in Form der DB Netz AG und die das Netz nutzenden Eisenbahnverkehrs-Unternehmen (EVUs, nach wie vor zumeist DB-Bahnen) innerhalb der DB-Holding konfundiert sind. Hieraus ergeben sich Diskriminierungspotenziale vor allem gegenüber DB-externen EVUs. Diese Situation entspricht keiner echten Netz-Betriebs-Trennung, die wettbewerbstheoretisch sinnvoll wäre und nachhaltige Konkurrenz verschiedener EVUs ermöglichen würde. Die seitens der DB zur Festigung bestehender Strukturen vertretene Argumentation, wonach Netz und Betrieb eine untrennbare Einheit (Synergie) bilden sollten, ist weder wettbewerbstheoretisch noch auf der Ebene technischer Aspekte akzeptabel. Vielmehr werden durch die gegenwärtige Verquickung der als Quasimonopol fungierenden Netzebene mit der Ebene der EVU-Leistungen Innovationspotenziale eingeschränkt. Abgesehen von der grundsätzlichen Notwendigkeit einer konsequenten Netz-Betriebs-Trennung und dezentraler Strukturen sind Ausschreibungen (faktisch öffentliches Verfahren) für den Betrieb der SPNV-Strecken als Handlungsansatz zu berücksichtigen. Wettbewerb kann auf diese Weise gleichsam an der Quelle einer EVU-Leistung ansetzen, wobei politische und administrative Widerstände gegen dieses Konzept derzeit noch unverkennbar sind. Hinsichtlich infrastruktureller Maßnahmen für den SPNV ist insbesondere das sog. "Betreibermodell" sinnvoll, bei dem sich das übernehmende EIU im Sinne seiner Kernkompetenzen auf den Betrieb konzentriert. Die Verantwortung für bauliche Maßnahmen sowie die Instandhaltung der Strecken liegt beim Betreiber, welcher derartige Leistungen am Markt einkaufen kann (Kostensenkungspotenzial). Bei Abgabeplanungen der DB Netz AG für eine Strecke ist mithin für die Auswahl eines Betreibers auf den genannten Ausschreibungsmodus zurückzugreifen. Als kostensenkende Einzelmaßnahmen zur Zukunftssicherung des SPNV werden abschließend insbesondere die Optimierung des Fahrzeugumlaufes sowie der Einsatz von Triebwagen anstatt lokbespannter Züge und die weiter forcierte Ausrichtung auf die kundenorientierte Attraktivitätssteigerung des SPNV empfohlen. SCHLUSSFOLGERUNGEN: Handlungsansätze für eine langfristige Sicherung des SPNV können nicht aus der Realisierung von Extrempositionen (staatlicher Interventionismus versus Liberalismus) resultieren, sondern nur aus einem pragmatischen Ausgleich zwischen beiden Polen. Dabei erscheint eine Verschiebung hin zum marktwirtschaftlichen Pol sinnvoll, um durch die Nutzung wettbewerbsbezogener Impulse Kostensenkungen und Effizienzsteigerungen für den SPNV herbeizuführen.

Tren d’alta velocitat i desenvolupament local urbà. Aportacions a una nova base teòrica

Una de les finalitats principals del tren d’alta velocitat és la d’aportar desenvolupament local en aquelles ciutats i territoris on se’n construeixi una estació. Per aquesta raó, calen reflexions teòriques que ajudin els agents i les institucions a planificar correctament l’arribada de la nova gran infraestructura de transport, especialment en els aspectes relacionats amb la capacitat d’organització dels actors territorials. La teoria reticular pot ser una base teòrica útil per evitar concepcions deterministes de la relació entre infraestructura i territori, per explicar com es produeix el procés de desenvolupament local i per demostrar la importància dels agents territorials en aquest procés

La organización de los actores en el desarrollo territorial: el tren de alta velocidad en la ciudad intermedia

If we want to evaluate the degree of local development that High-Speed Train (HST) provides in a city it is fundamental to observe the capacity of the actors of territory of organizing themselves to make use of their endogenous resources. Through the elaboration of a new methodology, the study of the process of development of three medium-sized cities with HST, Lérida (Spain), Avignon (France) and Novara (Italy), is suggested. As conclusion certain characteristic problems of intermediate city are shown in the execution of its local project, basically the existence of a troublesome multiscalar relationship and of a weak network of local actors. The fragility of this urban context is owed to the lack of correct processes of internal and external governance

Projecte d'instal·lació de caldera de vapor de 5.000 kg/h i serveis auxiliars per [a] una empresa situada a Vic

L’empresa RUSCALLEDA, S.L., ubicada a la localitat de Vic, es dedica a l’elaboració de productes alimentaris. La instal·lació actual de generació de calor utilitza una caldera antiga de combustible líquid i té una capacitat de producció de vapor de 1.500 kg/h. A causa de la demanda creixent de productes semielaborats, l'empresa vol instal·lar tres unitats noves de la línia final de productes semielaborats. Aquestes noves unitats tindrien un considerable consum d’energia calorífica en forma de vapor i requeririen actualitzar la instal·lació actual de producció i distribució de calor. L’objecte del projecte és la instal·lació d’un segon generador de vapor que sigui capaç d’alimentar la instal·lació actual més l’ampliació, quedant el generador actual en paral·lel per ser utilitzat en cas d’emergència

Allocation of GHG emissions in a paper mill, an application tool to reduce emissions

El sector de pasta i paper és considerat un dels set sectors industrials més intensius en consum energètic. La producció i consum d'electricitat i de vapor esdevenen les fonts majoritàries d'emissions de gasos d'efecte hivernacle en aquest sector industrial. Les fàbriques papereres poden assolir objectius de reducció d'emissions mitjançant reducció en origen (substitució de combustibles, introducció d'energies renovables) o bé a partir de mesures d'eficiència energètica en el propi procés. En aquest context, s'ha desenvolupat un mètode de distribució d'emissions que permet assignar a cada unitat d'operació del procés paperer, el seu grau de responsabilitat en emissions. També s'han avaluat diferents mètodes de càlcul de factors d'emissió de vapor i electricitat, tant per plantes de cogeneració com per sistemes individuals. A partir d'aquesta avaluació s'han proposat nous mètodes alternatius als analitzats. Aquests mètodes i els factors d'emissions s'han aplicat a dues fàbriques papereres catalanes.

O controlo de álcool e drogas e a sinistralidade laboral nos comboios de Portugal: tratamento dos dados

Embora o objectivo de redução de acidentes laborais seja frequentemente invocado para justificar uma aplicação preventiva de testes de álcool e drogas no trabalho, há poucas evidências estatisticamente relevantes do pressuposto nexo de causalidade e correlação negativa entre a sujeição aos testes e os posteriores acidentes. Os dados dos testes e dos acidentes ocorridos com os colaboradores de uma empresa transportadora portuguesa, durante anos recentes, são explorados, em busca de relações entre estas e outras variáveis biográficas. Os resultados preliminares obtidos sugerem que a sujeição a testes aleatórios no local de trabalho está associada a menos acidentes posteriores que os ocorridos na ausência desses testes, e que existe uma frequência óptima de testes acima da qual não se verifica redução de acidentes que justifique o investimento em aumento de testes. - Although the aim of reducing occupational accidents is frequently cited to justify preventive drug and alcohol testing at work, there is little statistically significant evidence of the assumed causality relationship and negative correlation between exposure to testing and subsequent accidents. Data mining of tests and accidents involving employees of a Portuguese transportation company, during recent years, searches for relations between these and other biographical variables. Preliminary results indicate that being subjected to random testing in the workplace is associated with fewer subsequent accidents that occur in the absence of such tests, and also that there is an optimum frequency of tests, above which there is no reduction of accidents to justify an increase of investment in testing.

Plano de contingência para laboração dos Comboios de Portugal em pandemia de gripe

O surgimento de um novo subtipo de vírus Influenza A, para o qual a população tem pouca imunidade, a capacidade do novo subtipo viral replicar em seres humanos e de provocar doença, conjugados com a capacidade de transmissão eficaz entre pessoas – como ocorrido com o vírus A[H1N1]v, em 2009, a partir do México – vieram concretizar a ameaça de pandemia de gripe que era esperada desde o início do século. Em resultado da grande morbilidade e do consequente e previsível aumento da mortalidade, são esperados impactos na laboração das Organizações, que se podem repercutir ao longo de toda a cadeia de serviços, podendo originar disfunções sociais e económicas. Transportando mercadorias estruturantes e cerca de meio milhão de passageiros por dia, a CP – Comboios de Portugal (CP), propagaria esses impactos negativos a muitas outras Organizações, se não conseguisse laborar nesse cenário. Não sendo possível adiar indefinidamente a pandemia, a estratégia adequada consiste no reforço da resiliência da Empresa e dos seus fornecedores críticos, para que toda a cadeia de serviços consiga dobrar sob a vaga de gripe, sem se partir, para retomar depois a operacionalidade desejada. A avaliação de riscos para a Empresa foi feita pesquisando o impacto de pandemias anteriores, projectando as solicitações dos clientes, determinando as funções de maior risco profissional de gripe e recorrendo aos dados epidemiológicos resultantes dos primeiros estudos publicados sobre o vírus A[H1N1]v. Para manter a continuidade da actividade essencial, a Empresa determinou o efectivo crítico para a produção dos comboios nos cenários de 10%, 25% e 50% de absentismo laboral. Foi iniciado o controlo de riscos de gripe, nomeadamente através de medidas de organização do trabalho, protecção colectiva, formação, informação e protecção individual. O dispositivo de protecção individual foi seleccionado para proteger o efectivo de forma diferenciada, conforme a sua criticidade para a laboração essencial da Empresa e o seu risco profissional de gripe. Estes e outros aspectos de Segurança e Saúde Ocupacionais são explorados no presente artigo, pelo papel determinante que assumem no Plano de Contingência para Laboração dos Comboios de Portugal em Pandemia de Gripe.

Development of a student workbook in conjunction with the Communication Skills Training for Professionals and Paraprofessionals Program

This paper discusses Communication Skills Training for Professionals and Paraprofessionals (ComPro), a program that trains professionals and paraprofessionals to communicate more effectively with their hearing-impaired clientele. This study assesses the usefulness of the ComPro in-service program and student workbook.

A survey of CTA train noise

This paper discusses a study of CTA commuter trains in Chicago and whether Chicago is in need of regulations of standards for noise emitted by CTA trains.

Two daily smoke maxima in eighteenth century London air

Varied electrostatics experiments followed Benjamin Franklin's pioneering atmospheric investigations. In Knightsbridge, Central London, John Read (1726–1814) installed a sensing rod in the upper part of his house and, using a pith ball electrometer and Franklin chimes, monitored atmospheric electricity from 1789 to 1791. Atmospheric electricity is sensitive to weather and smoke pollution. In calm weather conditions, Read observed two daily electrification maxima in moderate weather, around 9 am and 7 pm. This is likely to represent a double diurnal cycle in urban smoke. Before the motor car and steam railways, one source of the double maximum smoke pattern was the daily routine of fire lighting for domestic heating.

Granger causality of coupled climate processes: Ocean feedback on the North Atlantic oscillation

This study uses a Granger causality time series modeling approach to quantitatively diagnose the feedback of daily sea surface temperatures (SSTs) on daily values of the North Atlantic Oscillation (NAO) as simulated by a realistic coupled general circulation model (GCM). Bivariate vector autoregressive time series models are carefully fitted to daily wintertime SST and NAO time series produced by a 50-yr simulation of the Third Hadley Centre Coupled Ocean-Atmosphere GCM (HadCM3). The approach demonstrates that there is a small yet statistically significant feedback of SSTs oil the NAO. The SST tripole index is found to provide additional predictive information for the NAO than that available by using only past values of NAO-the SST tripole is Granger causal for the NAO. Careful examination of local SSTs reveals that much of this effect is due to the effect of SSTs in the region of the Gulf Steam, especially south of Cape Hatteras. The effect of SSTs on NAO is responsible for the slower-than-exponential decay in lag-autocorrelations of NAO notable at lags longer than 10 days. The persistence induced in daily NAO by SSTs causes long-term means of NAO to have more variance than expected from averaging NAO noise if there is no feedback of the ocean on the atmosphere. There are greater long-term trends in NAO than can be expected from aggregating just short-term atmospheric noise, and NAO is potentially predictable provided that future SSTs are known. For example, there is about 10%-30% more variance in seasonal wintertime means of NAO and almost 70% more variance in annual means of NAO due to SST effects than one would expect if NAO were a purely atmospheric process.

Generation of attosecond pulses in molecular nitrogen

We have generated attosecond pulse trains in an ensemble of randomly aligned nitrogen molecules. Measurements of the high-order harmonic relative phases and amplitudes allow us to reconstruct the temporal profile of the attosecond pulses. We show that in the considered spectral range, the latter is very similar to the pulse train generated in argon under the same conditions. We discuss the possible influence of the molecular structure in the generation process, and how it can induce subtle differences on the relative phases.

Crumpet structures: experimental and modelling studies

Crumpets are made by heating fermented batter on a hot plate at around 230°C. The characteristic structure dominated by vertical pores develops rapidly: structure has developed throughout around 75% of the product height within 30s, which is far faster than might be expected from transient heat conduction through the batter. Cooking is complete within around 3 min. Image analysis based on results from X-ray tomography shows that the voidage fraction is approximately constant and that there is continual coalescence between the larger pores throughout the product although there is also a steady level of small bubbles trapped within the solidified batter. We report here experimental studies which shed light on some of the mechanisms responsible for this structure, together with some models of key phenomena.Three aspects are discussed here: the role of gas (carbon dioxide and nitrogen) nuclei in initiating structure development; convective heat transfer inside the developing pores; and the kinetics of setting the batter into an elastic solid structure. It is shown conclusively that the small bubbles of carbon dioxide resulting from the fermentation stage play a crucial role as nuclei for pore development: without these nuclei, the result is not a porous structure, but rather a solid, elastic, inedible, gelatinized product. These nuclei are also responsible for the tiny bubbles which are set in the final product. The nuclei form the source of the dominant pore structure which is largely driven by the, initially explosive, release of water vapour from the batter together with the desorption of dissolved carbon dioxide. It is argued that the rapid evaporation, transport and condensation of steam within the growing pores provides an important mechanism, as in a heat pipe, for rapid heat transfer, and models for this process are developed and tested. The setting of the continuous batter phase is essential for final product quality: studies using differential scanning calorimetry and on the kinetics of change in the visco-elastic properties of the batter suggest that this process is driven by the kinetics of gelatinization. Unlike many thermally driven food processes the rates of heating are such that gelatinization kinetics cannot be neglected. The implications of these results for modelling and for the development of novel structures are discussed.