HETEROPHASE STEP-GROWTH POLYMERIZATION IN A CONTINUOUS TUBULAR REACTOR

The interfacial process is a well-established industrial process for the production of Bisphenol A polycarbonates. However, there is a dearth of kinetic analyses of the interfacial process in a tubular reactor, which offers greater overall control of this process. In the interfacial process, Bisphenol A dissolved in a dispersed aqueous phase reacts with phosgene in the continuous organic phase producing oligomers that undergo further reaction in the organic phase to produce polymers. This process was carried out in a tubular reactor at a constant pressure of 85 PSI and a constant temperature of 35°C. The kinetics of the mass transfer and reaction and the solubility of reactants were used to develop a mathematical model of the interfacial process in a tubular reactor. The parameters were optimized using proprietary plant data and the model simulations compared to the experimental data proved to be quite accurate. The developed model was used to investigate the heterophase kinetics of this system. A key parameter controlling the interfacial process in a tubular reactor is the dispersed aqueous droplet size. The droplet size determines the total surface area for mass transfer, and decreasing this droplet size from 10μm to 5μm results in an increase of molecular weight by about 130%. Also, the mass transfer coefficient of BPA (kL2) determines whether the processes at the interface are diffusion controlled or reaction controlled. The system exhibits diffusion controlled behavior when kL2 is approximately 1.0 × 10-7 m/s. Conversely, the system exhibits reaction controlled behavior when kL2 is around 4.0 × 10-6 m/s. The chain length distribution in the interfacial process follows Flory's most probable distribution. This functional group model was then expanded to a copolymerization system for siloxane-polycarbonate copolymers. For the copolymerization process, the key parameters shown to have a significant effect on the copolymer composition (mean sequence length and sequence length distribution) is the feed composition and reactivities of the comonomers

THEORY OF ONE-PHOTON HIGH-RESOLUTION ABSORPTION OPTICAL SPECTROSCOPY

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Economic Inequality and Political Participation in East Asian Democracies: The Role of Perceived Income Inequality and Intergenerational Mobility

This study examines how perceptions of economic inequality affect political participation focusing on East Asian democracies. It develops nuanced predictions on how perceptions of income inequality and social mobility and their interplay affect individuals’ engagement in various types of political activities in six East Asian democracies. Using the fourth wave of the Asian Barometer Survey, we examine novel arguments built upon the existing inequality-participation nexus. Our analysis suggests that inequality is a multifaceted concept, and the mechanisms of the inequality-participation nexus could vary depending on the regional, socioeconomic, and political context

Welfare stigmatization and the elderly: the case of the Supplemental Security Income program

Policy-makers and others historically have assumed that welfare programs should give assistance to the poor and carry stigma. This attitude in part developed from the English Poor Laws tradition in which poverty was considered a negative condition. Labeling theory has often been used to explain the process of welfare stigmatization. Once an individual is labeled as a deviant, such as a welfare recipient, a self-fulfilling prophecy is initiated. Others perceive and respond to the individual as a deviant and the individual also internalized the stigma attached to such a role. The stigma attached to public dependency becomes an outcome of this labeling process. This study identifies the relationship between welfare stigma and the elderly and has three objectives. First, it challenges the usefulness of labeling theory in explaining the perception of welfare stigma among elderly recipients. Second, it analyzes why different levels of stigma are attached to different public assistance programs. Third, it examines why some recipients feel more stigmatized than others. Historically, the elderly poor have heen identified as the deserving poor and provided for under most social programs. Because of differential treatment between the elderly poor and the able-bodied poor, this study contends that these groups develop different self-images as welfare recipients. A single welfare image applied indiscriminately to both groups results in a poor fit. Instead of internalizing the negative image from the outside community, the elderly may have internalized the deserving poor image and subsequently perceive their welfare status as less stigmatized. Congress established the Supplemental Security Income (SSI) program in 1972 to replace the state-run Old Age Assistance (OAA) program. By placing SSI under the Social Security Administration, this new program seeks to provide additional income with less stigma to the aged poor. Data for this study come from two separate surveys: a local survey of 400 respondents and a national survey of 8600 respondents. The most important dependent variable in this study is welfare stigma. It is operationally defined by three indicators: 1) whether recipients feel bothered in receiving assistance; 2) whether recipients feel embarrassed to admit their welfare status; and 3) whether recipients perceive community disrespect for thier welfare status. Factor analysis enabled a welfare stigma index to be constructed using the above three items. The often cited welfare stigma was not substantiated by the data. Elderly recipients of both OOA and SSI had low stigma feelings. Labeling theory, while useful in explaining welfare stigma of other poor subgroups, is not applicable to the elderly. Significantly less stigma was found to be associated with SSI than with OAA. Other findings supporting the SSI program include: more recipients had confidence in the Social Security Administration than in local welfare agencies; more were satisfied with the performance of SSI than with OAA; more non-recipients expressed a willingness to use SSI. In contrast to findings of many studies, this study found that some demographic variables, such as education and socioeconomic status, were significantly related to stigma. This study has theoretical and practical significance. First, it demonstrates that labeling theory is not useful in explaining stigma perception of the elderly. Second, it provides important baseline data to judge future performance of SSI and other similar programs. The analysis calls for the need to design effective social programs on a universalistic rather than class-specific basis. Options for change in the income-maintenance programs in the 1980\u27s are discussed and include an analysis of the two-tier proposal

Income Inequality, Social Mobility, and Electoral Participation in the U.S. Counties: Revisiting the Inequality-Participation Nexus

Previous research has provided contested hypotheses about the impact of income inequality on electoral participation. This study reexamines the debate between conflict and relative power theories by focusing on a largely ignored factor: social mobility. We argue that social mobility conditions the inequality-participation nexus by alleviating the frustration, class conflict, and efficacy gaps between the rich and the poor that the prevailing theories assume income inequality to create. By utilizing the Cooperative Congressional Election Survey, we test this argument focusing on US counties. Our analysis confirms that the effects of income inequality on citizens’ likelihood of voting vary depending on mobility, suggesting that social mobility provides a crucial context in which income inequality can play out in substantially different ways. This article implies that more scholarly endeavors should be made to clarify the multifaceted structure of inequality for improving our understanding of the relationship between economic and political inequality

A new vehicle for herbicide application using crude glycerin, a by-product of biodiesel production

The supply of glycerin derived from the pre-purification of biodiesel has increased considerably in Brazil, making it necessary to identify economic and environmentally friendly applications for this byproduct. This work aimed to develop oil-in-water (O/W) emulsions using crude glycerin treated with H3PO4 for use as a vehicle for the application the herbicide Togar. The work was conducted in the laboratory of Marlebologia at the Federal University of Tocantins, Gurupi Campus. The preliminary emulsions were subjected to stability testing, and those that remained stable were diluted with the herbicide Togar (8% v v-1) and characterized with respect to pH, conductivity, viscosity, density and surface tension. The crude glycerin was used to develop five stable emulsions with promising physicochemical characteristics for use as vehicle for herbicide application. The conductivity and viscosity of the emulsions were high compared to diesel.Key words: Agrochemicals, residue, emulsions

Shifting Focus in Development Studies : Papers in Development and Society , 1998-2013

How has development studies – especially the one on and in East Asia in general, and South Korea in particular – changed over the last decade and a half? We trace the recent trends through a review of articles published in Development and Society (D&S). Bibliographic metadata on a total of 201 authors and 199 papers for the period of 1998-2013 are collected and analyzed. For context, we find that, both in terms of authorship and regional coverage, the range of locales has expanded steadily. For content, research appears to have moved away from topics largely associated with quantity of development toward quality of development during the period. We conclude by discussing the implications for the future direction of development studies and suggesting strategies for D&S to follow in order to enhance its role in the field of development studies

Characterising standard genetic parts and establishing common principles for engineering legume and cereal roots

Plant synthetic biology and cereal engineering depends on the controlled expression of transgenes of interest. Most engineering in plant species to date has relied heavily on the use of a few, well-established constitutive promoters to achieve high levels of expression; however, the levels of transgene expression can also be influenced by the use of codon optimisation, intron-mediated enhancement and varying terminator sequences. Most of these alternative approaches for regulating transgene expression have only been tested in small-scale experiments, typically testing a single gene of interest. It is therefore difficult to interpret the relative importance of these approaches and to design engineering strategies that are likely to succeed in different plant species, particularly if engineering multi-genic traits where the expression of each transgene needs to be precisely regulated. Here we present data on the characterisation of 46 promoters and 10 terminators in Medicago truncatula, Lotus japonicus, Nicotiana benthamiana and Hordeum vulgare, as well as the effects of codon optimisation and intron-mediated enhancement on the expression of two transgenes in H. vulgare. We have identified a core set of promoters and terminators of relevance to researchers engineering novel traits in plant roots. In addition, we have shown that combining codon optimisation and intron-mediated enhancement increases transgene expression and protein levels in barley. Based on our study, we recommend a core set of promoters and terminators for broad use, and also propose a general set of principles and guidelines for those engineering cereal species