Oxide Semiconductors For Organic Opto-electronic Devices

Development of transparent oxide semiconductors (TOS) from Earth-abundant materials is of great interest for cost-effective thin film device applications, such as solar cells, light emitting diodes (LEDs), touch-sensitive displays, electronic paper, and transparent thin film transistors. The need of inexpensive or high performance electrode might be even greater for organic photovoltaic (OPV), with the goal to harvest renewable energy with inexpensive, lightweight, and cost competitive materials. The natural abundance of zinc and the wide bandgap ($sim$3.3 eV) of its oxide make it an ideal candidate. In this dissertation, I have introduced various concepts on the modulations of various surface, interface and bulk opto-electronic properties of ZnO based semiconductor for charge transport, charge selectivity and optimal device performance. I have categorized transparent semiconductors into two sub groups depending upon their role in a device. Electrodes, usually 200 to 500 nm thick, optimized for good transparency and transporting the charges to the external circuit. Here, the electrical conductivity in parallel direction to thin film, i.e bulk conductivity is important. And contacts, usually 5 to 50 nm thick, are optimized in case of solar cells for providing charge selectivity and asymmetry to manipulate the built in field inside the device for charge separation and collection. Whereas in Organic LEDs (OLEDs), contacts provide optimum energy level alignment at organic oxide interface for improved charge injections. For an optimal solar cell performance, transparent electrodes are designed with maximum transparency in the region of interest to maximize the light to pass through to the absorber layer for photo-generation, plus they are designed for minimum sheet resistance for efficient charge collection and transport. As such there is need for material with high conductivity and transparency. Doping ZnO with some common elements such as B, Al, Ga, In, Ge, Si, and F result in n-type doping with increase in carriers resulting in high conductivity electrode, with better or comparable opto-electronic properties compared to current industry-standard indium tin oxide (ITO). Furthermore, improvement in mobility due to improvement on crystallographic structure also provide alternative path for high conductivity ZnO TCOs. Implementing these two aspects, various studies were done on gallium doped zinc oxide (GZO) transparent electrode, a very promising indium free electrode. The dynamics of the superimposed RF and DC power sputtering was utilized to improve the microstructure during the thin films growth, resulting in GZO electrode with conductivity greater than 4000 S/cm and transparency greater than 90 %. Similarly, various studies on research and development of Indium Zinc Tin Oxide and Indium Zinc Oxide thin films which can be applied to flexible substrates for next generation solar cells application is presented. In these new TCO systems, understanding the role of crystallographic structure ranging from poly-crystalline to amorphous phase and the influence on the charge transport and optical transparency as well as important surface passivation and surface charge transport properties. Implementation of these electrode based on ZnO on opto-electronics devices such as OLED and OPV is complicated due to chemical interaction over time with the organic layer or with ambient. The problem of inefficient charge collection/injection due to poor understanding of interface and/or bulk property of oxide electrode exists at several oxide-organic interfaces. The surface conductivity, the work function, the formation of dipoles and the band-bending at the interfacial sites can positively or negatively impact the device performance. Detailed characterization of the surface composition both before and after various chemicals treatment of various oxide electrode can therefore provide insight into optimization of device performance. Some of the work related to controlling the interfacial chemistry associated with charge transport of transparent electrodes are discussed. Thus, the role of various pre-treatment on poly-crystalline GZO electrode and amorphous indium zinc oxide (IZO) electrode is compared and contrasted. From the study, we have found that removal of defects and self passivating defects caused by accumulation of hydroxides in the surface of both poly-crystalline GZO and amorphous IZO, are critical for improving the surface conductivity and charge transport. Further insight on how these insulating and self-passivating defects cause charge accumulation and recombination in an device is discussed. With recent rapid development of bulk-heterojunction organic photovoltaics active materials, devices employing ZnO and ZnO based electrode provide air stable and cost-competitive alternatives to traditional inorganic photovoltaics. The organic light emitting diodes (OLEDs) have already been commercialized, thus to follow in the footsteps of this technology, OPV devices need further improvement in power conversion efficiency and stable materials resulting in long device lifetimes. Use of low work function metals such as Ca/Al in standard geometry do provide good electrode for electron collection, but serious problems using low work-function metal electrodes originates from the formation of non-conductive metal oxide due to oxidation resulting in rapid device failure. Hence, using low work-function, air stable, conductive metal oxides such as ZnO as electrons collecting electrode and high work-function, air stable metals such as silver for harvesting holes, has been on the rise. Devices with degenerately doped ZnO functioning as transparent conductive electrode, or as charge selective layer in a polymer/fullerene based heterojunction, present useful device structures for investigating the functional mechanisms within OPV devices and a possible pathway towards improved air-stable high efficiency devices. Furthermore, analysis of the physical properties of the ZnO layers with varying thickness, crystallographic structure, surface chemistry and grain size deposited via various techniques such as atomic layer deposition, sputtering and solution-processed ZnO with their respective OPV device performance is discussed. We find similarity and differences in electrode property for good charge injection in OLEDs and good charge collection in OPV devices very insightful in understanding physics behind device failures and successes. In general, self-passivating surface of amorphous TCOs IZO, ZTO and IZTO forms insulating layer that hinders the charge collection. Similarly, we find modulation of the carrier concentration and the mobility in electron transport layer, namely zinc oxide thin films, very important for optimizing device performance.

Monetary Effervescence: A Sociological Theory of Religion Applied to Money

This project attempts to answer the question "What holds the construction of money together?" by asserting that it is money's religious nature which provides the moral compulsion for people to use, and continue to uphold, money as a socially constructed concept. This project is primarily descriptive and focuses on the religious nature of money by employing a sociological theory of religion in viewing money as a technical concept. This is an interdisciplinary work between religious studies, economics, and sociology and draws heavily from Emile Durkheim's 'The Elementary Forms of Religious Life' as well as work related to heterodox theories of money developed by Geoffrey Ingham, A. Mitchell Innes, and David Graeber. Two new concepts are developed: the idea of monetary sacrality and monetary effervescence, both of which serve to recharge the religious saliency of money. By developing the concept of monetary sacrality, this project shows how money acts to interpret our economic relations while also obfuscating complex power dynamics in society, making them seem naturally occurring and unchangeable. The project also shows how our contemporary fractional reserve banking system contributes to money's collective effervescence and serves to animate economic acting within a monetary network. The project concludes by outlining multiple implications for religious studies, economics, sociology, and central banking.

Desigualdades de género en salud laboral en España

Objetivos: Analizar las desigualdades de género en las condiciones de empleo, trabajo, conciliación de la vida laboral y familiar, y en los problemas de salud relacionados con el trabajo en una muestra de la población ocupada en España en el año 2007 teniendo en cuenta la clase social y el sector de actividad. Métodos: Las desigualdades de género se analizaron mediante 25 indicadores en los 11.054 trabajadores entrevistados en la VI Encuesta Nacional de Condiciones de Trabajo. Se calcularon las odds ratio (OR) y sus intervalos de confianza del 95% (IC95%) mediante modelos de regresión logística multivariados, estratificando por clase social ocupacional y sector de actividad. Resultados: Más mujeres que hombres trabajaban sin contrato (OR = 1,83; IC95%: 1,51-2,21), con alto esfuerzo o baja recompensa (1,14:1,05-1,25) y sufriendo acoso sexual (2,85:1,75-4,62), discriminación (1,60:1,26-2,03) y más dolores osteomusculares (1,38:1,19-1,59). Más hombres que mujeres trabajaban a turnos (0,86:0,79-0,94), con altos niveles de ruido (0,34:0,30-0,40), altas exigencias físicas (0,58:0,54-0,63) y sufriendo más lesiones por accidentes de trabajo (0,67:0,59-0,76). Las trabajadoras no manuales mostraron trabajar con un contrato temporal (1,34:1,09-1,63), expuestas a más riesgos psicosociales y sufriendo mayor discriminación (2,47:1,49-4,09) y enfermedades profesionales (1,91:1,28-2,83). En el sector de la industria las desigualdades de género fueron más marcadas. Conclusiones: En España existen importantes desigualdades de género en las condiciones de empleo, trabajo y en los problemas de salud relacionados con el trabajo, que se ven influenciadas por la clase social y el sector de actividad, y que sería necesario tener en consideración en las políticas públicas de salud laboral.

Differences in exposure to occupational health risks in Spanish and foreign-born workers in Spain (Itsal Project)

Migrant workers usually show higher rates of work-related health problems than natives. However, little information is available about their exposure to occupational risks. We describe self-reported working exposure in Spanish and foreign-born workers. A cross-sectional survey was conducted as part of the ITSAL Project. Data on sociodemographic and self-reported occupational exposure in 1,841 foreign-born and 509 Spanish workers were collected through face-to-face interviews. Prevalence and adjusted odds ratios-aOR- (by age, education, type of contract) were calculated. Foreign-born men in non-services sectors and those in manual occupations perceived exposure to occupational risks with lower prevalence than Spanish workers. Foreign-born women reported higher prevalence of exposure than Spanish female workers. By occupation, foreign-born female workers were more likely than Spanish workers to report working many hours/day (aOR2.68; 95 % CI 1.06–6.78) and exposure to extreme temperatures (aOR2.19; 95 % CI 1.10–4.38). Some groups of migrant workers may need increased protection regarding some occupational exposures.

La presencia de mobbing y sus determinantes laborales en profesores universitarios

En este artículo se analiza la presencia de mobbing en el profesorado universitario como parte de un estudio trasversal más amplio sobre su calidad de vida, trabajo y salud. Los objetivos del estudio son tres: 1) conocer la frecuencia del mobbing en un contexto universitario, 2) examinar la asociación existente entre mobbing y la edad, el género y la categoría académica de los profesores, y 3) estudiar los mejores predictores del mobbing. Respondieron el cuestionario 252 profesores a tiempo completo, lo que ha significado una tasa de respuesta del 61,6%. Nuestros resultados muestran que casi el veintitrés por ciento (22,6%) de los profesores se sintieron víctimas de mobbing. No hemos encontrado diferencias estadísticamente significativas en mobbing debidas a la edad, género o categoría académica de los profesores. Según diversos análisis de regresión logística jerárquica por bloques que hemos realizado, los mejores predictores del mobbing han resultado ser: el grado de autonomía en el trabajo y la satisfacción experimentada en las relaciones con los supervisores. Estas 2 variables han explicado, en nuestro estudio, casi un 37% de la variabilidad del mobbing. Serían necesarios estudios longitudinales o experimentales para poder establecer relaciones de causalidad entre mobbing y contexto laboral.

La Investigación en el área de Offshore Outsourcing de Sistemas de Información

El Offshore Outsourcing consiste en la externalización del trabajo relacionado con las Tecnologías de la Información a un proveedor localizado en un país diferente al cliente. Dado el creciente interés por el Offshore Outsourcing tanto en el mundo empresarial como académico, el presente trabajo realiza una revisión de la literatura en esta área. Se han analizado los artículos sobre el tema publicados en revistas de reconocido prestigio, examinando las metodologías de investigación, el nivel de análisis de los estudios, la perspectiva de datos, las teorías económicas más usadas, dónde se ubican los clientes y proveedores de estos servicios, qué tópicos son los más tratados y qué autores y países han aportado más hasta el momento en esta área. Las conclusiones destacan la falta de formalización teórica, el carácter fundamentalmente divulgativo y el mayor interés por conocer no sólo la perspectiva de los clientes sino también de los proveedores de estos servicios.

A relevância das medidas individualizadas : ouvimos o paciente mas captamos a história?

Individualized measures are relevant for the assessment of therapeutic results and allow patients to identify the aspects that they value the most in assessing their clinical improvement. PSYCHLOPS, as an individualized measure, invite the patient to create their own items. The items created by the patients were compared with the contents of standardized measures. A sample composed by 107 patients admitted for psychological treatment in Hospital Espírito Santo (Évora), and three institutions for drug misuse fill in the PSYCHLOPS and two standardized measures presented in a random order: CORE-OM and PHQ-9. 279 items were created in PSYCHLOPS and later recoded, by thematic analysis, in 51 subthemes. Work-related problems was the most common subtheme identified by patients as relevant to the clinical improvement assessment. From the 51 subthemes, 17 (33.3%) were not represented in CORE-OM and 43 (84.3%) were not represented in PHQ-9. The majority of our sample indicated at least one subtheme that was not represented in CORE-OM and PHQ-9. These results show us the importance of individualized measures in identifying the patients’ most value concerns, which may have implications in the therapeutic process.

Asset-backed securities: The key to unlocking Europe's credit markets? Bruegel Policy Contribution 2014/07, 24 July 2014

The European market for asset-backed securities (ABS) has all but closed for business since the start of the economic and financial crisis. ABS (see Box 1) were in fact the first financial assets hit at the onset of the crisis in 2008. The subprime mortgage meltdown caused a deterioration in the quality of collateral in the ABS market in the United States, which in turn dried up overall liquidity because ABS AAA notes were popular collateral for inter-bank lending. The lack of demand for these products, together with the Great Recession in 2009, had a considerable negative impact on the European ABS market. The post-crisis regulatory environment has further undermined the market. The practice of slicing and dicing of loans into ABS packages was blamed for starting and spreading the crisis through the global financial system. Regulation in the post-crisis context has thus been relatively unfavourable to these types of instruments, with heightened capital requirements now necessary for the issuance of new ABS products. And yet policymakers have recently underlined the need to revitalise the ABS market as a tool to improve credit market conditions in the euro area and to enhance transmission of monetary policy. In particular, the European Central Bank and the Bank of England have jointly emphasised that: “a market for prudently designed ABS has the potential to improve the efficiency of resource allocation in the economy and to allow for better risk sharing... by transforming relatively illiquid assets into more liquid securities. These can then be sold to investors thereby allowing originators to obtain funding and, potentially, transfer part of the underlying risk, while investors in such securities can diversify their portfolios... . This can lead to lower costs of capital, higher economic growth and a broader distribution of risk” (ECB and Bank of England, 2014a). In addition, consideration has started to be given to the extent to which ABS products could become the target of explicit monetary policy operations, a line of action proposed by Claeys et al (2014). The ECB has officially announced the start of preparatory work related to possible outright purchases of selected ABS1. In this paper we discuss how a revamped market for corporate loans securitised via ABS products, and how use of ABS as a monetary policy instrument, can indeed play a role in revitalising Europe’s credit market. However, before using this instrument a number of issues should be addressed: First, the European ABS market has significantly contracted since the crisis. Hence it needs to be revamped through appropriate regulation if securitisation is to play a role in improving the efficiency of resource allocation in the economy. Second, even assuming that this market can expand again, the European ABS market is heterogeneous: lending criteria are different in different countries and banking institutions and the rating methodologies to assess the quality of the borrowers have to take these differences into account. One further element of differentiation is default law, which is specific to national jurisdictions in the euro area. Therefore, the pool of loans will not only be different in terms of the macro risks related to each country of origination (which is a ‘positive’ idiosyncratic risk, because it enables a portfolio manager to differentiate), but also in terms of the normative side, in case of default. The latter introduces uncertainties and inefficiencies in the ABS market that could create arbitrage opportunities. It is also unclear to what extent a direct purchase of these securities by the ECB might have an impact on the credit market. This will depend on, for example, the type of securities targeted in terms of the underlying assets that would be considered as eligible for inclusion (such as loans to small and medium-sized companies, car loans, leases, residential and commercial mortgages). The timing of a possible move by the ECB is also an issue; immediate action would take place in the context of relatively limited market volumes, while if the ECB waits, it might have access to a larger market, provided steps are taken in the next few months to revamp the market. We start by discussing the first of these issues – the size of the EU ABS market. We estimate how much this market could be worth if some specific measures are implemented. We then discuss the different options available to the ECB should they decide to intervene in the EU ABS market. We include a preliminary list of regulatory steps that could be taken to homogenise asset-backed securities in the euro area. We conclude with our recommended course of action.

Avaliação da incidência de acidentes ocupacionais com potencial perigo biológico e implementação de medidas comportamentais corretivas em profissionais da veterinária

Nos dias de hoje, continua a assistir-se a elevados níveis de sinistralidade, no eventual reflexo de deficientes ou inexistentes estruturas de prevenção de riscos profissionais em muitos locais de trabalho. A necessidade de segurança, higiene, prevenção e formação no trabalho é, simultaneamente, uma reflexão sobre nós mesmos e as nossas atitudes, intervenientes prioritários, cada vez mais dependentes e exigentes com o trabalho e com tudo o que ele implica. Todavia, nos locais de trabalho são frequentemente criadas situações de perigo para a saúde e para a integridade física dos trabalhadores. A nível mundial, fontes ligadas à OMS (Organização Mundial da Saúde) e à OIT (Organização Internacional do Trabalho) referem que as condições de trabalho de cerca de 2/3 da população ativa estão abaixo dos padrões mínimos de qualidade, ou seja representam um risco real para a saúde e integridade física dos indivíduos. As estatísticas mundiais apontam para a existência de cerca de 157 milhões de novos casos de doenças profissionais por ano e de 120 milhões de acidentes de trabalho, dos quais 220 mil acidentes são fatais.

Psychological Ownership of Employees as a Mediator in the Justice - Affective Commitment Relationship

Numerous scholars have accumulated evidence on the positive effects that employees’ organizational justice perceptions exert on work-related outcomes such as affective commitment. However, research still lacks understanding of the underlying mechanisms connecting the two constructs. In this article we aim to narrow this gap by examining the concept of psychological ownership as a possible mediator between organizational justice perceptions and affective commitment. Investigating a sample of 619 employees, we find distributive justice to be positively related to psychological ownership, and observe psychological ownership as a full mediator of the distributive justice and affective commitment relationship. These insights offer a new explanation in understanding the justice-commitment connection, contributing to both organizational justice and psychological ownership literature and opening up ways for promising future research.

Handbook on workers' compensation and occupational diseases.

This handbook is designed to serve as a general guide to the rights and obligations of employees who have experienced work-related injuries on diseases, as well as the rights and obligations of their employers, under the Illinois Workers' Compensation and Occupational Diseases Act.

Handbook on workers' compensation and occupational diseases for injuries and illnesses on or after 6/28/11 /

This handbook is designed to serve as a general guide to the rights and obligations of employees who have experienced work-related injuries or diseases, as well as the rights and obligations of their employers, under the Illinois Workers' Compensation and Occupational Diseases Act.

Manual sobre compensacio n laboral y enfermedades ocupacionales.

This handbook is designed to serve as a general guide to the rights and obligations of employees who have experienced work-related injuries on diseases, as well as the rights and obligations of their employers, under the Illinois Workers' Compensation and Occupational Diseases Act.

Evaluation of the Feasibility of a Yoga and Mindfulness-Based Mental Health Intervention for Latina Immigrant Mothers

Thesis (Master's)--University of Washington, 2016-06

Job uncertainty and personal control during downsizing: A comparison of survivors and victims

This study developed and tested a model of job uncertainty for survivors and victims of downsizing. Data were collected from three samples of employees in a public hospital, each representing three phases of the downsizing process: immediately before the announcement of the redeployment of staff, during the implementation of the downsizing, and towards the end of the official change programme. As predicted, levels of job uncertainty and personal control had a direct relationship with emotional exhaustion and job satisfaction, In addition, there was evidence to suggest that personal control mediated the relationship between job uncertainty and employee adjustment, a pattern of results that varied across each of the three phases of the change event. From the perspective of the organization's overall climate, it was found that levels of job uncertainty, personal control and job satisfaction improved and/or stabilized over the downsizing process. During the implementation phase, survivors experienced higher levels of personal control than victims, but both groups of employees reported similar levels of job uncertainty. We discuss the implications of our results for strategically managing uncertainty during and after organizational change.