Flow injection analysis of ethyl xanthate by gas diffusion and UV detection as CS(2) for process monitoring of sulfide ore flotation

A sensitive and robust analytical method for spectrophotometric determination of ethyl xanthate, CH(3)CH(2)OCS(2)(-) at trace concentrations in pulp solutions from froth flotation process is proposed. The analytical method is based on the decomposition of ethyl xanthate. EtX(-), with 2.0 mol L(-1) HCl generating ethanol and carbon disulfide. CS(2). A gas diffusion cell assures that only the volatile compounds diffuse through a PTFE membrane towards an acceptor stream of deionized water, thus avoiding the interferences of non-volatile compounds and suspended particles. The CS(2) is selectively detected by UV absorbance at 206 nm (epsilon = 65,000 L mol(-1) cm(-1)). The measured absorbance is directly proportional to EtX(-) concentration present in the sample solutions. The Beer`s law is obeyed in a 1 x 10(-6) to 2 x 10(-4) mol L(-1) concentration range of ethyl xanthate in the pulp with an excellent correlation coefficient (r = 0.999) and a detection limit of 3.1 x 10(-7) mol L(-1), corresponding to 38 mu g L. At flow rates of 200 mu L min(-1) of the donor stream and 100 mu L min(-1) of the acceptor channel a sampling rate of 15 injections per hour could be achieved with RSD < 2.3% (n = 10, 300 mu L injections of 1 x 10(-5) mol L(-1) EtX(-)). Two practical applications demonstrate the versatility of the FIA method: (i) evaluation the free EtX(-) concentration during a laboratory study of the EtX(-) adsorption capacity on pulverized sulfide ore (pyrite) and (ii) monitoring of EtX(-) at different stages (from starting load to washing effluents) of a flotation pilot plant processing a Cu-Zn sulfide ore. (C) 2010 Elsevier By. All rights reserved.

Systemförvaltning hos Banverket – design av gemensam process för ändringshantering

Vår uppdragsgivare för detta arbete var IT-avdelningen på Banverkets huvudkontor. Deras upp-drag till oss var att kartlägga nuläget i ändringshanteringen i systemförvaltningen. Utifrån den kartläggningen skulle vi även utveckla en gemensam process med tillhörande processbeskrivning för ändringshanteringen. Ändringshantering är alla de aktiviteter som uppstår från det att ett förändringsbehov inkommer till dess att förändringen är införd. Banverket har under 2003 arbetat fram en metodik för systemförvaltning, som fortfarande är under utveckling. Metodikens stöd för det operativa arbetet, i synnerhet ändringshanteringen, är inte tillräcklig. Förvaltningsledare har hittills skapat sina egna processer kring hur ändringshan-teringen ska gå till och de finns inte dokumenterade, utan existerar som enskild kunskap. Detta leder till att systemförvaltningen blir personbunden och konsekvensen blir bland annat att det är resurskrävande att byta ut personen i förvaltningen samt att det tar längre tid vid överlämning av förvaltningen till ny person. Vi genomförde semistrukturerade intervjuer med nio systemförvaltare och förvaltningsledare för att kunna beskriva deras arbetssätt i nuläget. Till hjälp i beskrivningen av arbetssättet använde vi handlingsgrafer enligt metoden FA/SIM. Med handlingsgraferna kunde vi jämföra de olika arbetssätten. Vid jämförelsen kunde vi se att det fanns ett antal handlingar som är återkommande i de flesta nulägesbeskrivningarna. Vi analyserade dessa handlingar med hjälp av affärsaktsteorin för att få svar på om ändringshanteringen är affärstydlig. Vi kunde se att förvaltningsledarna saknar ett bra stöd för vilken information som bör komma in med varje förändringsbehov. Detta leder till att förvaltningsledaren känner en osäkerhet i om den prioriterat rätt och kan leda till att han/hon hamnar i ett underläge i en eventuell förhandling med leverantören. I acceptanstestningen märkte vi att den inte utförs på ett strukturerat sätt samt att det finns en tendens till att förvaltningsledaren i vissa fall förlitar sig på den testning leverantören utför. Den ändringshanteringsprocess vi utvecklat är en grund till ett gemensamt arbetssätt, men en viss fördjupning av detaljnivån i processen måste ske mot varje förvaltningsobjekt. Vi menar att för att säkerställa att rätt och jämförbar information om de olika förändringsbehoven kommer in behöver förvaltningsledaren arbeta fram någon form av frågemall. Genom att genomföra en nyt-tovärdering enligt PENG-modellen tror vi att förvaltningsledaren hittar de frågor som han/hon behöver ha svar på i prioriteringsfasen och som bör ingå i frågemallen. Acceptanstestningen bör ske på ett strukturerat sätt och vi föreslår att förvaltningsledaren arbetar fram ett testprotokoll för sitt förvaltningsobjekt samt identifierar några för verksamheten kritiska funktionaliteter som också bör ingå i testprotokollet.

Förekomst av peri-implantit 3 år efter Implantatinstallationen vid Centrum Oral Rehabilitering Parodontologi : En retrospektiv, beskrivande och jämförande journalstrudie

Implantatförankrad protetik har blivit ett vanligt behandlingsalternativ vid tandförlust.Tänder som förlorats på grund av karies, aplasi, trauma (olycksfall) eller parodontit (tandlossning) kan idag på många patienter ersättas med hjälp av implantat det vill säga en konstgjord tandrot av titan. Ett eller flera implantat opereras/installeras in i käkbenet och förses därefter med en krona, en bro eller en protes.Vävnaden runt implantatet kan drabbas av infektion på liknande sätt som vävnaden runt naturliga tänder och kallas då periimplantit. Detta är en reversibel inflammatorisk process i mjukvävnaden runt ett implantat med förlust av benvävnad.Syftet med studien var att beskriva förekomst av periimplantit hos patienter som erhållit implantat åren 2000-2001 vid Centrum Oral Rehabilitering, Parodontologi, samt förekomst av eventuella skillnader i periimplantit med avseende på rökvanor, kön och tidigare parodontal diagnos.Studien var en retrospektiv, beskrivande jämförande journalstudie.Totalt granskades 100 journaler, 80 journaler exkluderades då inte röntgenbilder togs tre år efter fixtur/implantat installation. Resultatet visade att 13 var kvinnor (65 %), 8 rökare (40 %) och 11 (55 %) personer hade remitterats för tidigare förekomst av parodontit.63 implantat installerades på 20 patienter. Periimplantit uppstod vid 8 implantat (13 %). Dessa implantat fanns hos 8 olika patienter, 5 var kvinnor, 5 rökare och 5 hade remitterats för parodontal diagnos. Något statistiskt samband kunde inte påvisas mellan förekomst av periimplantit och kön, rökvanor eller tidigare parodontal diagnos.Konklusionen: Förekomst av periimplantit under åren 2000-2001 var 13 %, vilket stämmer med tidigare studier.

Attractive Work Process

Many companies both in Sweden and other parts of the world are since the beginning of the 21st century faceing a lack of work force (1,2,3). The ability to recruit and retain skilled employees is seen as one of the most important questions for the survival and development of the companies (4,5). Labour shortage is seen as the biggest obstacle for expansion for small enterprises in Sweden (5). There is a need for workplaces to be attractive, but how can the attractiveness be increased? Researchers at Högskolan Dalarna have during almost a decennium conducted research concerning attractive work. Based on a modell of qualities that contributes to make a work attractive (6) has a method aiming for raised attractiveness been developed for SME:s. All employees participate by answering a questionnaire about the importance of different qualities and to what degree they are fulfilled. Further discussions at the workplace on what to preserve and what to develop make the base for an action plan.Important experiences:• Discuss and establish the aim of the method with management and employees. • The company must be prepared to follow up and realize the action plan.• Agree about expectations – they must be realistic and practicable.• Reserve time to start the process and to end up in an action plan. • Avoid negative thinking and put problems away. • Take all the time small steps in the right direction.• Keep employees engaged and avoid the manager or process leader to take the command.• Use the strategy with small work groups; it gives better possibilities for participation and outspokenness.• Follow up studies are necessary to keep up the motivation.The most positive aspects of the method is its promoting perspective and that it engages all the employees.1.Rauhut, D. (2002). Arbetskraftsbrist och arbetskraftsinvandring: hot eller möjlighet för ekonomisk tillväxt? Östersund, ITPS, Institutet för tillväxtpolitiska studier.2.Funch, M. and C. Ehrnooth. (2008, 08-10-2008). Labour shortage despite financial crisis? Retrieved 2008-12-16, 2008, from www.norden.org/webb/news/news.asp?id=8113&lang=6. 3.Manpower (2008). Talent Shortage Survey 2008 Global Results: 10. 4.Bakker, A. B. and W. B. Schaufeli (2008). Positive organizational behavior: Engaged employees in flourishing organizations. Journal of Organizational Behavior 29: 147-154.5.Kennemar, J. and L. Jagrén (2008). Småföretagsbarometern. Stockholm, Swedbank Företagarna: 23.6.Åteg, M., A. Hedlund, et al. (2004). Attraktivt arbete. Från anställdas uttalanden till skapandet av en modell. Stockholm, Arbetslivsinstitutet.

Le Petit Prince på franska : En undersökning om att läsa litteratur inom moderna språk på grundskola senare år

Den här studiens syfte är att undersöka om, hur och varför man kan läsa litteratur inom moderna språk, franska, på grundskola senare år. För att genomföra undersökningen har aktionsforskningsmetoden används, vilket innebär att forskaren deltog i den process som undersöktes som lärare. Studien har alltså två dimensioner: - Att planera, genomföra och utvärdera en verksamhet för en nionde klass som harmoniserar de nationella målen i moderna språk och studien av en litterär bok på franska (Le Petit Prince av Antoine de Saint-Exupéry). Att fundera på lärarens förhållningssätt. - Att undersöka elevernas lärande, uppfattning, förutsättningar, reaktioner och upplevelser genom enkäter och observationer. Studien visar att det är möjligt att harmonisera en undervisning baserad på litteratur med de nationella målen för moderna språk. En sådan undervisning kan främja kommunikation både muntligt och skriftligt. Den kan också utveckla elevernas medvetenhet om hur språkinlärningen går till, bland annat genom att ge dem insikt om de olika lässtrategierna och uppmuntra dem att lära sig anpassa lässtrategin med textens natur. Att litteratur utgör en del av kulturen bör dock förstärkas hos eleverna. Boken Le Petit Prince kännetecknas av underlättande särdragen och erbjuder samtidigt en rimlig utmaning. Bokens tema var inte lika motiverande för alla elever och några elever fick svårigheter i samband med deras språknivå. Studien visar dock att elevernas arbetsvanor spelar en avgörande roll i nyttan av undervisning baserad på litteratur både vad det gäller deras förhållningssätt och hur de upplever svårigheterna. Användning av lärobokstexter i språkundervisningen främjar bottom up-läsning och installerar vanor som kan hindra en top downläsning vid långa och autentiska texter. Att utveckla nya vanor anses alltså vara nödvändigt för att utnyttja språkundervisningen baserad på litteratur optimalt. Variation visar sig vara ett nyckelbegrepp då eleverna behöver uppmuntras och utmanas genom varierande aktiviteter och uppgifter. Detta gäller både inom språkundervisningen baserad på litteratur så som språkundervisningen i övrigt. Litteratur anses alltså vara ett bra komplement till läroböcker.

”Det är ju troligen inte en overheadapparat de kommer att använda sig av i framtiden…” : Om skolans tekniksprång, en undersökning om datorns användning på gymnasiet

The aim of this qualitative respondent investigation is to delve into the various views that teachers have concerning the “One-to-One project”, as well as the use of computers as an aid in teaching. One-to-One means that teachers and students will be equipped with a laptop they can use at home and at school.This essay looks at how several factors have changed as a result of this. These factors are threefold: the role of the teacher, the teaching experience, and the student´s learning process. In order to answer the mentioned questions, four interviews have been conducted at two different high schools in southern Norrland. The theory used is the socio-cultural perspective. One result has been that computers can simplify teaching in various ways. Students have faster access to information, and there exists a platform for further communication between the teacher and student outside the classroom. However, there are also several negative aspects. One of these is that the students spend time doing non-school related activities, such as interacting using social mediums. Results also show that the role of the teacher has due to the "One-to-One project" gone from being structural to being interactional. The conclusions reached by the investigation are that today’s schools are experiencing a paradigm shift. Old teaching methods are being replaced by new methods and an altered teaching practice has developed as a result of the presence of the computer in the classroom.

Akademisk kvalitet, vad är det? : Om utarmningen av den akademiska autonomin

What is academic quality? On the decline of academic autonomy In light of the transformations that universities currently undergo, with Bologna as a keyword, the following questions are put: What ideals lie behind the assessment of academic “excellence” and “quality”? What agents have the ability to define what is good science and education today? These questions are approached through Pierre Bourdieus concept of field. Looking at the development the last decade, traditional academic values, such as the ideal of universal knowledge as (personal and collective) enrichment and the intellectual independence “of all political authority and economic power”, as stated in the Magna Charta Universitatum, seem to have emerged into the shadow of employability, knowledge control, competitiveness, and economic benefit. In connection with the formation of concepts such as “the knowledge society” and “knowledge based economies” the university has received a somewhat different and more central role in society. The university has come to take the role more of a knowledge producing enterprise clearly directed towards the surrounding society. There are higher demands on academic knowledge to contribute to economic, regional or national development and competitiveness. When the university is regarded as a knowledge company whose task is to accoun tfor the requests of the students, the labour market, and the business world it undertakes to follow trends and short term social phases rather than to critically examine them, which has been a traditional task for the university. If the academic work is guided by the market economical principle, that the client requests decide what quality is, instead of the experts on the academic field themselves (i.e. the scientists,) it is obviously not scientific ideals that constitute the criteria for what is good science and education.

Det är enklare i teorin… Om skolutveckling i praktiken : En fallstudie av ett skolutvecklingsprojekt i en gymnasieskola

This dissertation is a case study dealing with a school development project that took place in an upper secondary school as a result of a merger of two schools with different cultures. The project used a method called “Frirumsmodellen” and was planned to be conducted in three steps. The first was to carry out a cultural analysis in order to map the preconditions to start a school development project. The second was to carry out concrete actions and finally study eventual effects from such activities by doing a second cultural analysis. My role was to be a supervisor in the school development work, but at the same time study how this work was conducted and its impact in the ordinary school day. The dissertation takes its departure in the fact that schools are political governed. The mission of schools is never neutral; it is always an expression of behind laying social forces, ideologies and ideals of the contemporary society. Of this reason, there is a close connection between the macro political level and the micro political level. Another point of departure is the transition from a modern to a post modern society that gives the character to the changes that take place in schools. Steering of schools has partly been treated as a technical implementation problem. Schools contain on going conflicts between different interest groups that, more or less regularly, end up in educational reforms. These reforms generate school development activities in the single school. Undoubtedly, this makes school development to a complex process. At a rather late stage of the study I decided not to fulfil my task to follow the original plan. I instead let the school development project as a model to be in focus. The over all purpose was formulated: How is it possible to understand what happened in the school development project in the Falkgymnasiet and why was it not possible to carry it out as it was said in the project plan? To interpret what took place during the project I did create an interpretation frame of implementation and complexity theory that also made it possible to critically scrutinise the “Frirumsmodellen”. Already in an early stage of the process it was obvious that the “Frirumsmodellen” did not supply any tools to use and it became disconnected from the project. The project in it selves was marginalised and made invisible. The headmaster used the situation to change things she thought were important to develop. As a result, things happened, but most of the involved people did not at first hand connect this to the project. It is, of course, difficult in detail to say what caused what. The complexity theory successively made the hidden patterns revealed, hidden unofficial potentates visible, as well as unpredictable conditions that generated reactions from the personnel in front of a development work. Together this was rather efficient obstacles for not changing this school. I also discuss school development and implementation problems on a general level, for example, the possibility to transform a top-down initiated project to be bottom-up driven and using project as a tool for school development work. It was obvious that headmasters and teachers must be prepared to handle the ideological dimensions of problems schools have to face. Consequently, development work is about making problems visible and to handle these in the intersection point between the intentions of educational policies, pedagogical researchers, school administrators, headmasters, teachers and pupils. The ideological dimension also contains an existential issue. Do I as a teacher share the intentions for the development work? If not, how must I act?

Duplication of R&D and industry concentration

The purpose of the literature on Research Joint Ventures (RJV), pioneered by DíAspremont and Jacquemin (1988) and Kamien, Muller, and Zang (1992), has been to combine the best of two worlds: to appropriately deal with R&D spillovers while preserving competition in the product market. Moreover, RJVs eliminate duplication of R&D. Thus, at least in theory, RJVs dominate other solutions such as subsidies. If, however, we are concerned about risks of cartelization, then Spenceís (1984) subsidy-based solution for independently acting firms, is a viable alternative that cannot be dismissed. Indeed, in contrast to the previous literature, we find that in the presence of R&D subsidies, market performance may unambiguously improve with the number of firms in the market.

Integrating open innovation in the social innovation process: an exploratory study

Inovação tem se tornado um fenômeno cada vez mais complexo e dinâmico, com a mudança de um paradigma focado na inovação industrial, onde a inovação acontecia no produto ou no processo de fabricação, para outro baseado no conhecimento, muito mais amplo. Além disso, o conhecimento e a competência técnica não são mais considerados como um monopólio do departamento de pesquisa e desenvolvimento. Isto trouxe mudanças nas práticas de inovação, que se tornaram mais abertas e levaram as empresas a interagir cada vez mais com o seu ambiente. Por outro lado, a inovação tecnológica, cujo primeiro objetivo é de criar valor para a empresa, tem experimentado alguns limites para resolver problemas sociais, como o aquecimento global. As novas tecnologias têm a capacidade de melhorar a qualidade de vida de muita gente, mas não é suficiente. É nesse contexto que surge outro tipo de inovação, cujo objetivo é de maximizar o impacto positivo na sociedade: a inovação social. Estes dois paradigmas de inovação, mais adequados aos desafios atuais, têm alguns pontos em comum na sua integração com o ambiente externo: a sociedade e outros atores da inovação. No entanto, praticamente não existem estudos integrando inovação aberta e inovação social. Este trabalho estuda a integração destes dois modelos a partir de uma pesquisa exploratória, realizando entrevistas em profundidade com 11 dirigentes de organizações sociais. As iniciativas sociais parecem atrair mais organizações externas para colaborar do que empresas com fins lucrativos, já que são mais altruístas. Parecem integrar essas pessoas e procurar por mais ajuda, especialmente no momento de escalar o negócio. Ainda que algumas organizações têm como prioridade institucionalizar a inovação aberta, outras veem isto como secundário ou simplesmente não sabem como fazer. Isto resulta em uma colaboração mais informal, que não é focada em atividades de pesquisa e desenvolvimento, prática ausente nas empresas da nossa amostra.

Mover/se(r) a gênese do corpo entre/corpos e seus trajetos no processo coreográfico

This paper proposes a reflection on the body between/bodies, especially in contemporary dance, in their path that starts from the choreographic construction, permeating the body of the choreographer, the dancer s body and when fulfills themselves as artistic expression, the body of the spectator. Initially discusses the body in dance as a body/space for convergence, connectedness and continuity, from the thought of the Greek philosopher Epicurus of Samos, in dialogue with the thought of Maurice Merleau-Ponty, Gilles Deleuze and José Gil. Reflect about the creation of this body/space in the relationship choreographer/dancer using as connecting thread the experiences of the author in his artistic path. Finally describes the process of creating the scenic experiment (h)áporos, which constitutes the practice scene of this dissertation, having as main objective the creation of spaces of convergence and interaction between a proponent and an affluent body that, in this move, transforms itself and the space that now cohabits / is

The influence of the scout upon the decision-making process of recruited workers in three Acromyrmex species (Formicidae : Attini)

We examined how the information communicated by a scout worker influences the plant species transported by recruited workers in Acromymex balzani, Acromyrmex rugosus, and Acromyrmex crassispinus, three species of leaf-cutting ant that have different substrate and habitat preferences. We verified that certain plant species were more likely to be transported than others and that recruitment occurs. We found that recruited workers were more likely to transport non-preferred plant species when they were recruited to these by scout workers. The results suggest that the scout worker can communicate information about plant identity to recruited workers, but that recruited workers integrate the information communicated with their own experience during the decision-making process. (C) 2004 Published by Elsevier B.V.

Theoretical analysis of the energy levels induced by oxygen vacancies and the doping process (Co, Cu and Zn) on SnO2 (110) surface models

Density functional calculation at B3LYP level was employed to study the surface oxygen vacancies and the doping process of Co, Cu and Zn on SnO2 (110) surface models. Large clusters, based on (SnO2)(15) models, were selected to simulate the oxidized (Sn15O30), half-reduced (Sn15O29) and the reduced (Sn15O28) surfaces. The doping process was considered on the reduced surfaces: Sn13Co2O28, Sn13Cu2O28 and Sn13Zn2O28. The results are analyzed and discussed based on a calculation of the energy levels along the bulk band gap region, determined by a projection of the monoelectron level structure on to the atomic basis set and by the density of states. This procedure enables one to distinguish the states coming from the bulk, the oxygen vacancies and the doping process, on passing from an oxidized to a reduced surface, missing bridge oxygen atoms generate electronic levels along the band gap region, associated with 5s/5p of four-/five-fold Sn and 2p of in-plane O centers located on the exposed surface, which is in agreement with previous theoretical and experimental investigations. The formation energy of one and two oxygen vacancies is 3.0 and 3.9 eV, respectively. (C) 2001 Elsevier B.V. B.V. All rights reserved.

In-process grinding monitoring by acoustic emission

This work aims to investigate the efficiency of digital signal processing tools of acoustic emission signals in order to detect thermal damages in grinding process. To accomplish such a goal, an experimental work was carried out for 15 runs in a surface grinding machine operating with an aluminum oxide grinding wheel and ABNT 1045. The acoustic emission signals were acquired from a fixed sensor placed on the workpiece holder. A high sampling rate data acquisition system at 2.5 MHz was used to collect the raw acoustic emission instead of root mean square value usually employed. Many statistics have shown effective to detect burn, such as the root mean square (RMS), correlation of the AE, constant false alarm (CFAR), ratio of power (ROP) and mean-value deviance (MVD). However, the CFAR, ROP, Kurtosis and correlation of the AE have been presented more sensitive than the RMS.