881 resultados para 330205 Curriculum Studies - Other Social Sciences, Humanities and Arts Education
Resumo:
The present work attempts to trace the variation in the physical and chemical behavior of ilmenite, since its release from country rocks and subsequent transportation to the coast through the progressive weathering environments of laterite, sedimentary rocks, rivers and estuarine systems. Since the hinterland of the study area consists of crystalline and sedimentary rocks and their weathered forms (laterites), the contribution of each lithological system to the beach placer is attempted. The results of the study show that the most magnetic fraction contains more content of altered phases than the relatively unweathered fractions. The fractions separated above 0.35A define a high grade of ilmenite ore enriched in Ti content. The lattice volume generally decreases with alteration. The magnetic studies revels that the Chavara ilmenite are found to be made up to low magnetic crops with about 46% of the bulk ilmenite constituted by fractions separated at above 0.35A. In the Manavalakurichi ilmenite on the other hand, around 91% of the beach ilmenite is made of fractions separated at or below 0.3A
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In the first part of the study we probed the effectiveness of rice bran oil as a multipurpose compounding ingredient for nitrile (NBR) and chloroprene (CR) rubbers. This oil has already been successfully employed in the compounding of NR and SBR in this laboratory.In this context we thought it worthwhile to try this oil in the polar rubbers viz, NBR and CR also. The principle of like dissolves like as applicable to solvents is equally applicable while selecting a plasticiser, elastomer combination. Because of the compatibility considerations polar plasticisers are preferred for polar rubbers like NBR and CR. Although plasticisation is a physical phenomenon and no chemical reaction is involved, the chemical structure of plasticisers determines how much physical attraction there is between the rubber and the plasticiser. In this context it is interesting to note that the various fatty acids present in rice bran oil have a long paraffinic chain, characteristic of waxes, with an acid group at the end of the molecule. The paraffinic end of the molecule contributes lubricating effects and limits compatibility whereas the acid end group contributes some polarity and is also chemically reactive. Because of absorption of acid group on the surface of pigments, these acids will have active pigment wetting characteristics also. These factors justifies the role of rice bran oil as a co-activator and lubricating agent for NBR and CR. In fact in our study we successfully replaced stearic acid as co-activator and aromatic oillDOP as processing aid for CR and NBR with rice bran oil.This part of the study has got special significance in the fact that rubber industry now heavily depends on petroleum industry for process oils. The conventional process oils like aromatic, naphthenic and paraffinic oils are increasingly becoming costlier, as its resources in nature are fast depleting. Moreover aromatic process oils are reported to be carcinogenic because of the presence of higher levels of polycyclic aromatic compounds in these oils.As a result of these factors, a great amount research is going on world over for newer processing aids which are cost effective, nontoxic and performanance wise at par with the conventional ones used in the rubber industry. Trials with vegetable oils in this direction is worth trying.Antioxidants are usually added to the rubber compound to minimise ageing effects from heat, light, oxygen etc. As rice bran oil contains significant amount of tocopherols and oryzanol which are natural antioxidants, we replaced a phenolic antioxidant like styrenated phenol (SP) from the compound recipe of both the rubbers with RBO and ascertained whether this oil could function in the role of antioxidant as well.Preparation and use of epoxidised rice bran oil as plasticiser has already been reported.The crude rice bran oil having an iodine value of 92 was epoxidised in this laboratory using peracetic acid in presence of sulphuric acid as catalyst. The epoxy content of the epoxidised oil was determined volumetrically by treating a known weight of the oil with excess HCI and back titrating the residual HCI with standard alkali solution. The epoxidised oil having an epoxy content of 3.4% was tried in the compounding of NBR and CR as processing aids. And results of these investigations are also included in this chapter. In the second part of the study we tried how RBO/ERBO could perform when used as a processing aid in place of aromatic oil in the compounding of black filled NRCR blends. Elastomers cannot have all the properties required for a particular applications, so it is common practice in rubber industry to blend two elastomers to have desired property for the resulting blend.In this RBO/ERBO was tried as a processing aid for plasticisation, dispersion of fillers, and vulcanisation of black filled NR-CR blends.Aromatic oil was used as a control. The results of our study indicate that these oils could function as a processing aid and when added together with carbon black function as a cure accelerator also.PVC is compatible with nitrile rubber in all proportions, provided NBR has an acrylonitrile content of 25 to 40%. Lower or higher ACN content in NBR makes it incompatible with PVC.PVC is usually blended with NBR at high temperatures. In order to reduce torque during mixing, additional amounts of plasticisers like DOP are added. The plasticiser should be compatible both with PVC and NBR so as to get a homogeneous blend. Epoxidised soyaben oil is reported to have been used in the compounding of PVC as it can perfonn both as an efficient plasticiser and heat stabilizer.At present DOP constitute the largest consumed plasticiser in the PVC compounding. The migration of this plasticiser from food packaging materials made of PVC poses great health hazards as this is harmful to human body. In such a scenario we also thought it worthwhile to see whether DOP could be replaced by rice bran oil in the compounding of NBR-PVC blends Different blends of NBR-PVC were prepared with RBO and were vulcanized using sulphur and conventional accelerators. The various physical and mechanical properties of the vulcanisates were evaluated and compared with those prepared with DOP as the control plasticiser. Epoxidised rice bran oil was also tried as plasticiser for the preparation of NBR-PVC blends. A comparison of the processability and cure characteristics of the different blends prepared with DOP and ERBO showed that ERBO based blends have better processability and lower cure time values. However the elastographic maximum torque values are higher for the DOP based blends. Almost all of the physical properties evaluated are found to be slightly better for the DOP based blends over the ERBO based ones. However a notable feature of the ERBO based blends is the better percentage retention of elongation at break values after ageing over the DOP based blends. The results of these studies using rice bran oil and its epoxidised variety indicated that they could be used as efficient plasticisers in place of DOP and justifies their role as novel, nontoxic, and cheap plasticisers for NBR-PVC blends.
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The present study deals with the different hydrogeological characteristics of the coastal region of central Kerala and a comparative analysis with corresponding hard rock terrain. The coastal regions lie in areas where the aquifer systems discharge groundwater ultimately into the sea. Groundwater development in such regions will require a precise understanding of the complex mechanism of the saline and fresh water relationship, so that the withdrawals are so regulated as to avoid situations leading to upcoming of the saline groundwater bodies as also to prevent migration of sea water ingress further inland. Coastal tracts of Kerala are formed by several drainage systems. Thick pile of semi-consolidated and consolidated sediments from Tertiary to Recent age underlies it. These sediments comprise phreatic and confined aquifer systems. The corresponding hard rock terrain is encountered with laterites and underlined by the Precambrian metamorphic rocks. Supply of water from hard rock terrain is rather limited. This may be due to the small pore size, low degree of interconnectivity and low extent of weathering of the country rocks. The groundwater storage is mostly controlled by the thickness and hydrological properties of the weathered zone and the aquifer geometry. The over exploitation of groundwater, beyond the ‘safe yield’ limit, cause undesirable effects like continuous reduction in groundwater levels, reduction in river flows, reduction in wetland surface, degradation of groundwater quality and many other environmental problems like drought, famine etc.
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Blogging has become one of the key ingredients of the so-called socials networks. This phenomenon has indeed invaded the world of education. Connections between people, comments on each other posts, and assessment of innovation are usually interesting characteristics of blogs related to students and scholars. Blogs have become a kind of new form of authority, bringing about (divergent) discussions which lead to creation of knowledge. The use of blogs as an innovative, educational tool is not at all new. However, their use in universities is not very widespread yet. Blogging for personal affairs is rather commonplace, but blogging for professional affairs – teaching, research and service, is scarce, despite the availability of ready-to-use, free tools. Unfortunately, Information Society has not reached yet enough some universities: not only are (student) blogs scarcely used as an educational tool, but it is quite rare to find a blog written by University professors. The Institute of Computational Chemistry of the University of Girona and the Department of Chemistry of the Universitat Autònoma de Barcelona has joined forces to create “InnoCiència”, a new Group on Digital Science Communitation. This group, formed by ca. ten researchers, has promoted the use of blogs, twitters. wikis and other tools of Web 2.0 in activities in Catalonia concerning the dissemination of Science, like Science Week, Open Day or Researchers’ Night. Likewise, its members promote use of social networking tools in chemistry- and communication-related courses. This communication explains the outcome of social-network experiences with teaching undergraduate students and organizing research communication events. We provide live, hands-on examples and interactive ground to show how blogs and twitters can be used to enhance the yield of teaching and research. Impact of blogging and other social networking tools on the outcome of the learning process is very depending on the target audience and the environmental conditions. A few examples are provided and some proposals to use these techniques efficiently to help students are hinted
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Libro orientado a servir de guía a los estudiantes universitarios en la redacción de ensayos, exámenes e informes de investigación en el área de las Ciencias Sociales, analizando tanto sus requerimientos específicos como los preceptos generales para una escritura eficaz. Una redacción adecuada en esta área requiere no sólo un buen estilo, sino también una buena comprensión del diseño de la investigación, la teoría, las mediciones, los argumentos y la comunicación. Para ello el libro señala los errores más comunes en las redacciones de los estudiantes e indica cómo evitarlos y corregirlos, y proporciona orientación en métodos de investigación, evaluación de fuentes de información, plagio y cuestiones éticas, programas de presentación de contenidos y bibliografía.
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This paper provides resources to help hearing impaired students in primary and elementary grades with personal and social competency training.
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The physical and emotional changes that occur in adolescence are part of the process of sexual maturity. These changes occur irrespective of ability and are often aligned with psychological and social factors. When the nature of a disability has an inherent limitation in social awareness, as is the case for individuals with autism, the achievement of personal sexual identity can become much more complex. Challenges in supporting individuals in this respect can be caused by the sensitive aspects of inappropriate behaviour, the abstract nature of teaching the topic, and the general reluctance on the part of parents and staff to discuss sexuality in individuals with disabilities. This article explores how a residential school addressed this gap. It provides details of how this need was met for seven students and the process undertaken to involve staff, parents and other stakeholders to establish ongoing support.
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Internationally in secondary schools, lessons are typically taught by subject specialists, raising the question of how to accommodate teaching which bridges the sciences and humanities. This is the first study to look at how students make sense of the teaching they receive in two subjects (science and religious education) when one subject’s curriculum explicitly refers to cross-disciplinary study and the other does not. Interviews with 61 students in seven schools in England suggested that students perceive a permeable boundary between science and their learning in science lessons and also a permeable boundary between religion and their learning in RE lessons, yet perceive a firm boundary between science lessons and RE lessons. We concluded that it is unreasonable to expect students to transfer instruction about cross-disciplinary perspectives across such impermeable subject boundaries. Finally we consider the implications of these findings for the successful management of cross-disciplinary education.
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My research aims to understand how and why fundamentalists justify violence against people who do not fit their profile of "righteous" or "saved" persons, such as abortion doctors and clinic workers, gays and lesbians, and Jews. The first section of this paper travels through the history of fundamentalism since its origins in the British and American apocalipticism, or belief in the Second Coming of Jesus Christ. However, my history of Protestant Fundamentalism in the United States will focus on the ways in which Fundamentalism developed in response to many changes in American social structure. I interpret Fundamentalism as an anti-modern movement seeking to reassert "traditional" Christian values.
Resumo:
Social Entrepreneurship (SE) has attracted growing interest from a wide variety of actors over the last 30 years, especially due to a general agreement that it could be an important tool for tackling many of the world’s social ills. In the academic sphere, this growing interest did not translate into a matured field of study. Quite the opposite, a quick look at this literature makes it evident that: SE has been consistently subjected to numerous theoretical discussions and disagreements, especially over the definition of the concept of SE which is often based on a taken-for-granted notion of social change; it has been more systematically investigated in restricted contexts, often leaving aside so called developing/emerging countries like Brazil and especially lacking in-depth qualitative studies; SE literature lags behind SE practices and few studies focus on how SE actually occurs in a daily and bottom-up manner. In order to address such gaps, this thesis examines how social entrepreneurship practices accomplish social change in the context of Brazil. In this investigation I conducted an inductive practice-based, qualitative/ethnographic study in three Non-Governmental Organizations (NGOs) located in different cities in the Brazilian state of São Paulo. Data collection lasted from February 2014 until March 2015 and was mainly done through participant observations and through in-depth unstructured conversations with research participants. Secondary data and documents were also collected whenever available. The participants of this study included a variety of the studied organizations’ stakeholders: two founders, volunteers, employees, donors and beneficiaries. Observation data was kept in fieldnotes, conversations were recorded whenever possible and were later transcribed. Data was analyzed through an iterative thematic analysis. Through this I identified eight recurrent themes in the data: (1) structure; (2) relationship with other organizational actors (sub-themes: relationship with state, relationship with businesses and relationship with other NGOs); (3) beliefs, spirituality and moral authority; (4) social position of participants, (5) stakeholders’ mobilization and participation; (6) feelings; (7) social purpose; and (8) social change. These findings were later discussed under the lens of practice theory, and in this discussion I argue and show that, in the context studied: (a) even though SE embraces a wide variety of different social purposes, they are intertwined with a common notion of social change based on a general understanding and aspiration for social equality; (b) this social change is accomplished in a processual and ongoing manner as stakeholders from antagonistic social groups felt compelled to and participated in SE practices. In answering the proposed research question the contributions of this thesis are: (i) the elaboration a working definition for SE based on its relationship with social change; (ii) providing in-depth empirical evidence which accounts for and explains this relationship; (iii) characterizing SE in the Brazilian context and reflecting upon its transferability to other contexts. This thesis also makes a methodological contribution, for it demonstrates how thematic analysis can be used in practice-based studies.