18 resultados para LDH grafoil ERGO GO capacitori ibridi PEDOT:PSS

em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland


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Polymeric materials that conduct electricity are highly interesting for fundamental studies and beneficial for modern applications in e.g. solar cells, organic field effect transistors (OFETs) as well as in chemical and bio‐sensing. Therefore, it is important to characterize this class of materials with a wide variety of methods. This work summarizes the use of electrochemistry also in combination with spectroscopic methods in synthesis and characterization of electrically conducting polymers and other π‐conjugated systems. The materials studied in this work are intended for organic electronic devices and chemical sensors. Additionally, an important part of the presented work, concerns rational approaches to the development of water‐based inks containing conducting particles. Electrochemical synthesis and electroactivity of conducting polymers can be greatly enhanced in room temperature ionic liquids (RTILs) in comparison to conventional electrolytes. Therefore, poly(para‐phyenylene) (PPP) was electrochemically synthesized in the two representative RTILs: bmimPF6 and bmiTf2N (imidazolium and pyrrolidinium‐based salts, respectively). It was found that the electrochemical synthesis of PPP was significantly enhanced in bmimPF6. Additionally, the results from doping studies of PPP films indicate improved electroactivity in bmimPF6 during oxidation (p‐doping) and in bmiTf2N in the case of reduction (n‐doping). These findings were supported by in situ infrared spectroscopy studies. Conducting poly(benzimidazobenzophenanthroline) (BBL) is a material which can provide relatively high field‐effect mobility of charge carriers in OFET devices. The main disadvantage of this n‐type semiconductor is its limited processability. Therefore in this work BBL was functionalized with poly(ethylene oxide) PEO, varying the length of side chains enabling water dispersions of the studied polymer. It was found that functionalization did not distract the electrochemical activity of the BBL backbone while the processability was improved significantly in comparison to conventional BBL. Another objective was to study highly processable poly(3,4‐ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) water‐based inks for controlled patterning scaled‐down to nearly a nanodomain with the intention to fabricate various chemical sensors. Developed PEDOT:PSS inks greatly improved printing of nanoarrays and with further modification with quaternary ammonium cations enabled fabrication of PEDOT:PSS‐based chemical sensors for lead (II) ions with enhanced adhesion and stability in aqueous environments. This opens new possibilities for development of PEDOT:PSS films that can be used in bio‐related applications. Polycyclic aromatic hydrocarbons (PAHs) are a broad group of π‐conjugated materials consisting of aromatic rings in the range from naphthalene to even hundred rings in one molecule. The research on this type of materials is intriguing, due to their interesting optical properties and resemblance of graphene. The objective was to use electrochemical synthesis to yield relatively large PAHs and fabricate electroactive films that could be used as template material in chemical sensors. Spectroscopic, electrochemical and electrical investigations evidence formation of highly stable films with fast redox response, consisting of molecules with 40 to 60 carbon atoms. Additionally, this approach in synthesis, starting from relatively small PAH molecules was successfully used in chemical sensor for lead (II).

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In modern society, the body health is a very important issue to everyone. With the development of the science and technology, the new and developed body health monitoring device and technology will play the key role in the daily medical activities. This paper focus on making progress in the design of the wearable vital sign system. A vital sign monitoring system has been proposed and designed. The whole detection system is composed of signal collecting subsystem, signal processing subsystem, short-range wireless communication subsystem and user interface subsystem. The signal collecting subsystem is composed of light source and photo diode, after emiting light of two different wavelength, the photo diode collects the light signal reflected by human body tissue. The signal processing subsystem is based on the analog front end AFE4490 and peripheral circuits, the collected analog signal would be filtered and converted into digital signal in this stage. After a series of processing, the signal would be transmitted to the short-range wireless communication subsystem through SPI, this subsystem is mainly based on Bluetooth 4.0 protocol and ultra-low power System on Chip(SoC) nRF51822. Finally, the signal would be transmitted to the user end. After proposing and building the system, this paper focus on the research of the key component in the system, that is, the photo detector. Based on the study of the perovskite materials, a low temperature processed photo detector has been proposed, designed and researched. The device is made up of light absorbing layer, electron transporting and hole blocking layer, hole transporting and electron blocking layer, conductive substrate layer and metal electrode layer. The light absorbing layer is the important part of whole device, and it is fabricated by perovskite materials. After accepting the light, the electron-hole pair would be produced in this layer, and due to the energy level difference, the electron and hole produced would be transmitted to metal electrode and conductive substrate electrode through electron transporting layer and hole transporting layer respectively. In this way the response current would be produced. Based on this structure, the specific fabrication procedure including substrate cleaning; PEDOT:PSS layer preparation; pervoskite layer preparation; PCBM layer preparation; C60, BCP, and Ag electrode layer preparation. After the device fabrication, a series of morphological characterization and performance testing has been done. The testing procedure including film-forming quality inspection, response current and light wavelength analysis, linearity and response time and other optical and electrical properties testing. The testing result shows that the membrane has been fabricated uniformly; the device can produce obvious response current to the incident light with the wavelength from 350nm to 800nm, and the response current could be changed along with the light wavelength. When the light wavelength keeps constant, there exists a good linear relationship between the intensity of the response current and the power of the incident light, based on which the device could be used as the photo detector to collect the light information. During the changing period of the light signal, the response time of the device is several microseconds, which is acceptable working as a photo detector in our system. The testing results show that the device has good electronic and optical properties, and the fabrication procedure is also repeatable, the properties of the devices has good uniformity, which illustrates the fabrication method and procedure could be used to build the photo detector in our wearable system. Based on a series of testing results, the paper has drawn the conclusion that the photo detector fabricated could be integrated on the flexible substrate and is also suitable for the monitoring system proposed, thus made some progress on the research of the wearable monitoring system and device. Finally, some future prospect in system design aspect and device design and fabrication aspect are proposed.

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Turku : J.W. Lillja & Co. 1854

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The purpose of the research is to develop a go-to-market strategy with pharmacies. As it was agreed with the client of the study, Reckitt Benckiser, the focus is solely on non-prescription products. Therefore, prescription medicines are not considered in the study. The main objective of the research is to clarify consumer and pharmacy personnel behavior concerning non-prescription products. These issues are observed with surveys, which are provided to consumers and pharmacy personnel. The go-to-market strategy is based on the survey results and is comprised by utilizing the marketing-mix model. Legislation and the present state & trends are additional minor research problems of the study. The results of the research provide many descriptive insights about consumer and pharmacy personnel behavior. It is concluded that the consumers’ level of involvement with non-prescription products is low and the type of behavior is habitual. It is also demonstrated that several decision-making criteria are very different among different age groups and genders. Concerning pharmacy personnel, the factors that they base their product recommendations are revealed. In addition, the sources of medicine information for both consumers and pharmacy personnel are found out.

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Tutkimuksen tarkoituksena on selvittää taitojen opettamisen kolmen askeleen menetelmän soveltuvuutta motoristen taitojen opetukseen käsityön 4. luokalla. Menetelmän soveltuvuuden testaamiseksi on suunniteltu ja valmistettu oppimistehtävä. Oppimistehtävä on laadittu taitojen opettamisen yleismenetelmän, kolmen askeleen menetelmän pohjalta. Oppimistehtävän laadinnassa on käytetty tukena myös suljetun oppimistehtävän teoreettista perustaa, sekä ositetun ja taitolajipainotteisen käsityön piirteitä. Oppimistehtävä toteutettiin satakuntalaisessa koulussa ja toteutuksen suoritti koulun oma käsityönopettaja. Oppimistehtävän aikana tapahtuvasta toiminnasta, opetuksesta ja oppimisessa on pyritty saamaan tietoa kaikilta siihen osallistuneilta osapuolilta. Oppilaille on suoritettu oppimista mittaava alku ja loppu kysely. Opettajaa on haastateltu, jolloin on saatu oppimistehtävän toteuttajan kokemuksia tapahtuneesta. Lisäksi tutkijat ovat itse osallistuneet toiminnan havainnointiin, sekä videoineet opetusta ja oppilaiden toimintaa. Tutkimus on tutkimusotteeltaan laadullinen tapaustutkimus. Tutkimuksen tuote on motoristen taitojen opettamiseen laadittu oppimistehtävä. Tutkimuksen kulku ja toteutus on kuvattu yksityiskohtaisesti mittarien laadinnasta, aineiston keruun ja -tulosten analysoinnin kautta synteesiin ja tutkimusongelmiin vastaamiseen. Tutkimuksen tulokset osoittavat, että taitojen opettamisen kolmen askeleen menetelmä sisältää myös perusopetuksessa toteutettavan taitojen opetuksen kannalta keskeisimmät elementit. Menetelmä soveltuu etenkin vasta-alkaneille opettajille, mutta myös kokeneille opettajille. Taitojen oppimisen kannalta erityisen tärkeäksi seikaksi tällä ikäryhmällä osoittautui demonstrointi ja ohjaaminen. Lisäksi saimme yksityiskohtaista tietoa, jonka avulla menetelmästä voisi laatia tälle ikäryhmälle vieläkin sopivamman.

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Esitys Kirjastoverkkopäivillä 25.10.2012 Helsingissä

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This study examines the aftermath of mass violence in local communities. Two rampage school shootings that occurred in Finland are analyzed and compared to examine the ways in which communities experience, make sense of, and recover from sudden acts of mass violence. The studied cases took place at Jokela High School, in southern Finland, and at a polytechnic university in Kauhajoki, in western Finland, in 2007 and 2008 respectively. Including the perpetrators, 20 people lost their lives in these shootings. These incidents are part of the global school shooting phenomenon with increasing numbers of incidents occurring in the last two decades, mostly in North America and Europe. The dynamic of solidarity and conflict is one of the main themes of this study. It builds upon previous research on mass violence and disasters which suggests that solidarity increases after a crisis, and that this increase is often followed by conflict in the affected communities. This dissertation also draws from theoretical discussions on remembering, narrating, and commemorating traumatic incidents, as well as the idea of a cultural trauma process in which the origins and consequences of traumas are negotiated alongside collective identities. Memorialization practices and narratives about what happened are vital parts of the social memory of crises and disasters, and their inclusive and exclusive characteristics are discussed in this study. The data include two types of qualitative interviews; focused interviews with 11 crisis workers, and focused, narrative interviews with 21 residents of Jokela and 22 residents of Kauhajoki. A quantitative mail survey of the Jokela population (N=330) provided data used in one of the research articles. The results indicate that both communities experienced a process of simultaneous solidarity and conflict after the shootings. In Jokela, the community was constructed as a victim, and public expressions of solidarity and memorialization were promoted as part of the recovery process. In Kauhajoki, the community was portrayed as an incidental site of mass violence, and public expressions of solidarity by distant witnesses were labeled as unnecessary and often criticized. However, after the shooting, the community was somewhat united in its desire to avoid victimization and a prolonged liminal period. This can be understood as a more modest and invisible process of “silent solidarity”. The processes of enforced solidarity were partly made possible by exclusion. In some accounts, the family of the perpetrator in Jokela was excluded from the community. In Kauhajoki, the whole incident was externalized. In both communities, this exclusion included associating the shooting events, certain places, and certain individuals with the concept of evil, which helped to understand and explain the inconceivable incidents. Differences concerning appropriate emotional orientations, memorialization practices and the pace of the recovery created conflict in both communities. In Jokela, attitudes towards the perpetrator and his family were also a source of friction. Traditional gender roles regarding the expression of emotions remained fairly stable after the school shootings, but in an exceptional situation, conflicting interpretations arose concerning how men and women should express emotion. The results from the Jokela community also suggest that while increased solidarity was seen as important part of the recovery process, some negative effects such as collective guilt, group divisions, and stigmatization also emerged. Based on the results, two simultaneous strategies that took place after mass violence were identified; one was a process of fast-paced normalization, and the other was that of memorialization. Both strategies are ways to restore the feeling of security shattered by violent incidents. The Jokela community emphasized remembering while the Kauhajoki community turned more to the normalization strategy. Both strategies have positive and negative consequences. It is important to note that the tendency to memorialize is not the only way of expressing solidarity, as fast normalization includes its own kind of solidarity and helps prevent the negative consequences of intense solidarity.

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Julkaisussa: General hydrographisk chart-book öfwer Östersjön och Katte-Gatt till sin raetta figur och stoorleek