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1
Edmark, Marcus, und Olle Benzler. „Measurement Method Analysis of Photonic CO2 Sensor“. Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-200580.
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Zhu, Yongming [Verfasser]. „CO2 sensor based on lithium ion conductor / Yongming Zhu“. Kiel : Universitätsbibliothek Kiel, 2009. http://d-nb.info/1019813350/34.
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Válek, Vít. „Flexibilní bezdrátový systém pro měření CO2 v budově“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442452.
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Monitoring of the carbon dioxide concentration in the building is carried out for several reasons. One is to ensure hygiene conditions. With the advent of Bluetooth 5.0 came the support of mesh network technology, which is defined by the Bluetooth Mesh standard. By implementing this standard, we can create an extensive network of devices monitoring the concentration of carbon dioxide in the building. Based on the monitored concentration, we can control the air conditioning and ventilation of the spaces, ensuring that the hygiene conditions are met. Thanks to the compatibility of Bluetooth Mesh with Bluetooth Low Energy, it is possible to access individual nodes, e.g. from a mobile phone. The aim of this work is to design and implement a measuring system whose elements will communicate with each other using Bluetooth Mesh wireless technology.
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Nygård, Skalman Jonas. „CO2 Sensor Core on FPGA : ASIC prototyping and cost estimates“. Thesis, Mittuniversitetet, Avdelningen för elektronikkonstruktion, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-35963.
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Demand of CO2 gas sensors is expected to continue to increase in the foreseeable future, due to an increasing awareness of air pollution and fossil fuel emissions. A truly low cost and accurate NDIR sensor has the potential of greatly benefiting the environment by an increased human awareness due to CO2 measurements. In the objective to reach these goals, a CO2 sensor core on an ASIC needs to be investigated. In this study an ASIC prototype design is tested on an FPGA and evaluated towards logic resource requirements, power analysis and estimated cost impacts towards a full ASIC. The results show that a potential ASIC implementation would have a very small cost impact on a full system design if the use of a preexisting ASIC design is utilized. Using a manufacturing process of 180 nm, the total logic implementation would require between 0.54-0.76 mm2. The cost impact of such a logic area would be around $0.025 USD per chip. The power consumption of the logical part would also be very small when compared to the various analog components of a full system design.
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Schaeffer, Robson Dagmar. „Estudo e desenvolvimento de um sensor de CO2 de baixo custo“. reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2004. http://hdl.handle.net/10183/4199.
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Este trabalho descreve um estudo e desenvolvimento de um sensor de dióxido de carbono (CO2), de baixo custo, para monitoramento da qualidade do ar em ambientes climatizados. O sensor aqui proposto baseia-se na técnica de absorção em infravermelho não dispersivo (NDIR). Este trabalho avalia alguns métodos já empregados e propõe um modelo alternativo visando uma solução de baixo custo que possa ser incorporada a sistemas de monitoramento e/ou condicionamento existentes, permitindo o controle do teor de CO2. A metodologia inclui o estudo dos diferentes tipos de sensores de CO2, a seleção da técnica mais apropriada para medição, o estudo das alternativas para implementação da técnica selecionada, o desenvolvimento, testes e avaliações da solução. Especificamente desenvolveu-se uma solução em termos de sensor de CO2 que utiliza componentes comerciais, sendo facilmente reprodutível e de custo reduzido. O sensor desenvolvido tem faixa de medição entre 330 a mais de 10000 ppm, com resolução estimada em torno de 20 a 30 ppm, com erro em relação ao padrão menor que 10% da medição ou 150 ppm,o que for maior.
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Kuutmann, Hanna, und Emelie Rosén. „Smartphone Capnography : Evaluation of the concept and the associated CO2 indicating sensor“. Thesis, KTH, Medicinsk teknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-152640.
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Smartphone capnography is a new concept for respiratory monitoring using a colorimetric sensor in combination with a smartphone and an Android application. Compared to using an infrared spectrophotometric carbon dioxide analyzer (IR-analyzer), the gold standard for respiratory carbon dioxide monitoring, smartphone capnography offers a cheaper and less bulky solution. This master thesis evaluates the performance of smartphone capnography and the colorimetric sensor engineered for this concept. Three different techniques (side stream, shunt stream and main stream) were tested. Additionally, an iPhone application was developed as a proof of concept when using an iPhone for smartphone capnography. An experimental set-up simulating human breathing was assembled and measurements, at different breathing rates (6-30 breaths/min) and carbon dioxide levels (2-7vol%), were performed with an IR-analyzer as reference. Results showed that capnograms from smartphone capnography was comparable to those from the IR-analyzer and that the approximate accuracy was ±0.25vol% for up to 6 days of use. Results strongly motivate further elaboration of the concept and the three different techniques for measuring.”Smartphone capnography” är ett nytt koncept för att monitorera andning. Principen är en kombination av en kolorimetrisk sensor, en smartphone samt en Androidapplikation. Jämfört med den dominerande tekniken, en IR-spektrofotometrisk koldioxidanalysator (IR-analysator), så är “smartphone capnography” både billigare och mindre skrymmande. Detta examensarbete utvärderar konceptet ”smartphone capnography” och en kolorimetrisk sensor speciellt utvecklad för ändamålet. Tre olika tekniker (side stream, shunt stream och main stream) har utvärderats. Slutligen utvecklades en iPhoneapplikation för att visa att konceptet ”smartphone capnography” kan användas även med denna typ av smartphone. Utvärderingen bestod i att göra mätningar i en experimentell uppställning som simulerar andning. Mätningar gjordes vid varierande andningsfrekvenser (6-30 andetag/min) och koldioxidnivåer (2-7vol%). Mätdata från ”smartphone capnography” jämfördes med mätdata från en IR-analysator. Resultaten visar att kapnogram från ”Smartphone capnography” är jämförbara med kapnogram från IR-analysatorn och att den uppskattade noggrannheten är ±0,25vol% för upp till 6 dagars användning. De goda resultaten motiverar fortsatt utveckling av konceptet smartphone capnography samt de olika mätteknikerna.
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Zuo, Ziwei. „Fabrication of intensity-based Long-Period-Gratings fiber sensor with CO2 Laser“. Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/54599.
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This thesis investigates the fabrication technique and procedures for producing long period grating (LPG) fiber sensors with point-by-point irradiation under a CO2 laser beam. The type of fiber sensor under examination is desirable to be highly sensitive to the variation of the thickness and refractive index of a thin film deposited on the LPGs, making it a promising candidate as a core sensor component in a biosensor system developed for detection and verification of pathogenic bacteria, such as Methicillin-resistant Staphylococcus aureus (MRSA), Francisella tularensis, and so on.
We have previously demonstrated that a UV-induced long-period-grating (LPG) based fiber sensor is extremely sensitive to small variation of refractive index (RI) and thickness of the surrounding medium. In this thesis, we will present a CO2 laser and step- stage system that operate automatically under control of a Matlab program to inscribe LPGs with desired grating period and fabrication conditions.
Examples of CO2 laser induced LPGs have been found to exhibit high sensitivity, with transmissive power attenuation of more than 15 dB at the resonant peak of 1402 nm under deposition of Ionic Self-Assembled Monolayer (ISAM) thin film that is around 50 nm in thickness. When tuned to its maximum sensitivity region, this LPG has shown a transmission power reduction of 79% with the deposition of only 1 bilayer of ISAM thin film at the monitored wavelength. This result is comparable in sensitivity with the UV-induced LPGs, yet with the advantage of lower fabrication cost and simplified fabrication procedure.Master of Science
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Lee, Chong-Hoon. „Study of reversible electrode reaction and mixed ionic and electronic conduction of lithium phosphate electrolyte for an electrolchemical co2 gas sensor“. The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1073047249.
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Yoon, Junro. „A Study of Interface Reaction of Li0.35La0.55TiO3-Li2CO3 and Its Effect on Potentiometric CO2 Gas Sensors“. The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1354666091.
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Borkar, Chirag. „Development of Wireless Sensor Network System for Indoor Air Quality Monitoring“. Thesis, University of North Texas, 2012. https://digital.library.unt.edu/ark:/67531/metadc177181/.
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This thesis describes development of low cost indoor air quality (IAQ) monitoring system for research. It describes data collection of various parameters concentration present in indoor air and sends data back to host PC for further processing. Thesis gives detailed information about hardware and software implementation of IAQ monitoring system. Also discussed are building wireless ZigBee network, creating user friendly graphical user interface (GUI) and analysis of obtained results in comparison with professional benchmark system to check system reliability. Throughputs obtained are efficient enough to use system as a reliable IAQ monitor.
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Peňák, Vlastimil. „Návrh kontrolního přípravku pro plastový výrobek interiéru osobního vozidla“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241711.
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This diploma thesis deals with the development, disign and manufacturing inspection device that is able to detect the presence of components in the assembly of the plastic molding. Evaluation of information are indicated by the operator device and sent for further processing. Rechecked product will be marked with a uniquemark.
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Lander, Jasmine. „Cost-efficient approaches to measure carbon dioxide (CO2) under different environmental factors such as temperature and humidity using mini loggers“. Thesis, Linköpings universitet, Institutionen för tema, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-165993.
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Fluxes of carbon dioxide (CO2), being a major greenhouse gas, are of great importance to understand and monitor. Findings have shown that while CO2 emissions enhanced by humans triggered the greenhouse gas effect, several significant CO2 fluxes in nature that are climate sensitive may still be poorly constrained, especially those from inland waters and its surrounding soils and sediments. This including different processes such as decomposers degrading organic material. At present, direct measurements of CO2 from soils, waters or CO2 concentrations in surface water, are typically labour intensive or require costly equipment. Therefore, small inexpensive CO2 mini loggers, originally made for indoor air quality monitoring, are for this project being developed further for field use, as a convenient equipment to measure CO2 emissions. However, a requirement is that the mini loggers are stable and robust against interference by other air components, including water vapour, and physical factors such as temperature. Therefore, the mini loggers were for this project studied further under different environmental conditions such as temperature and humidity in a controlled environment. The results were analysed using multiple regression analysis where the CO2 concentration (CO2), measured by the LGR instrument, versus the logger IR signal (IR), temperature (T) and relative humidity (RH) were studied. Unlike some previous studies, this project studied a large CO2 concentration interval (400 – 10 000 ppm). The results show that there was a strong regression for IR versus CO2. The regression for both RH and the T was on the other hand very weak. However, there were factors that could have affected the mini logger. This since it was noticed that the mini loggers’ ability to calculate the CO2 concentration was worsened when the humidity was increased during the experiments. It is believed that the cause was condensed water, gathering in the inner parts of the mini logger. This because the sensor chamber had a lower temperature than the hot air entering the sensor chamber from the humidity bottle, together with the CO2, leading to condensation. Hence, prevention of condensation inside the measurement cell is important. However, the results from the analysis shows that the factors; RH and T do not need to be taken into account when studying the CO2 concentration over a larger interval, as long as the conditions are not condensing.
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Machýček, David. „Konstrukce bioinkubátoru pro transport buněčných kultur“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230378.
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In a research part, this diploma thesis deals with dividing incubators into groups according to their kind of use. From the groups biological incubators have been chosen to describe their construction, to explain possibilities of doing sampling and temperature and CO2 control. The research part is concluded by an overview of biological transport incubators for a transfer of cell cultures. In the part of the thesis which deals with a new construction solution some variations are suggested. The most suitable variation has been chosen after a structural technological description, and it is further described in a constructional solution. The frame of the incubator is made from aluminium alloy and is controlled by FEM. There are individual structural nodes being explained and visualised step by step in the construction solution. In the end of the construction solving some information about making the construction and prices of all continuing manufacture are stated.
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Bučko, Ondrej. „Efektivní řízení technologií budov s důrazem na měření vlhkosti a koncentrace CO2“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442540.
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The diploma thesis deals with automated measurement of humidity and CO2 concentration inside buildings. Results of this measurement form the input parameters for the effective management of technologies reducing the energy performance of buildings. In the introduction, the issue of indoor air quality of buildings and indicators characterizing this quality are approached. The technical part of the thesis consists of making a measuring device which contains two prototype sensors provided by Teco Inc. with online access to measured data. The measurement of relative humidity, CO2 concentration and temperature in the interior of the building with the made device is compared with commercially available devices for measuring selected parameters. For unambiguous interpretation of online data, the virtual machine with an online database is configured for the created measuring device. The possibilities of using the prepared measuring device to achieve a reduction in the energy performance of buildings are discussed in the final part.
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Sebem, Renan. „Customização de sensibilidade de sensores a redes de período longo em fibras ópticas monomodo padrão e aplicações“. Universidade do Estado de Santa Catarina, 2015. http://tede.udesc.br/handle/handle/2086.
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This work explores the potential and shows the implementation of the long period gratings as refractive index sensors. It is proposed a sensor design where the refractive index sensitivity is improved. The design includes the use of the sensor with simple and low cost interrogation. Several manufacturing parameters are investigated and the process is enhanced to meet the design specifications, and also to obtain repeatability in the process. New ideas were proposed to manufacture tilted gratings and to control the index modulation duty cycle in a practical way with inexpensive equipment. The inscription of the fiber sensor is made by CO2 laser, point to point, with a uniform index modulation. The gratings were interrogated by an optical spectrum analyzer and also by edge filter demodulation in the 1550 nm region through an electronic board, developed in this work with automatic normalization of the signal. Results show that the refractive index sensitivity is influenced by several design and manufacturing parameters of the fiber grating. Performed experiments show a considerable increase in the refractive index sensitivity of the grating.
Este trabalho explora o potencial e demonstra a implementação das redes de período longo em fibra como sensores de índice de refração. É proposto um projeto do sensor em que a sensibilidade ao índice de refração é aperfeiçoada. O projeto contempla a utilização do sensor com interrogação de maneira simples e de baixo custo. Diversos parâmetros de fabricação são investigados e o processo é aprimorado para atingir as especificações de projeto, e também a fim da obtenção de repetibilidade no processo. Novas ideias foram propostas para fabricação de redes inclinadas e para o controle do duty cycle da modulação de índice da rede de maneira prática com equipamentos de baixo custo. A fabricação do sensor em fibra é feita através de laser de CO2, ponto a ponto, e com modulação de índice uniforme. As redes foram interrogadas através de analisador de espectro óptico e também por demodulação de borda de filtro na região de 1550 nm através de uma placa eletrônica, desenvolvida neste trabalho com normalização automática do sinal. Resultados mostram que a sensibilidade ao índice de refração é influenciada por alguns parâmetros de projeto e fabricação da rede em fibra. Experimentos realizados mostraram um aumento considerável na sensibilidade da rede ao índice de refração.
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Aiyar, Avishek R. „Microfabrication of a MEMS piezoresistive flow sensor - materials and processes“. Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24696.
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Canning, Anna [Verfasser], Arne [Akademischer Betreuer] Körtzinger und Bernhard [Gutachter] Wehrli. „Greenhouse gas observations across the Land-Ocean Aquatic Continuum: Multi-sensor applications for CO2, CH4 and O2 measurements / Anna Canning ; Gutachter: Bernhard Wehrli ; Betreuer: Arne Körtzinger“. Kiel : Universitätsbibliothek Kiel, 2020. http://d-nb.info/1211649261/34.
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Lan, Lijuan [Verfasser], Jia [Akademischer Betreuer] Chen, Jia [Gutachter] Chen und Mark [Gutachter] Wenig. „Development of a CO2 sensor using TDLAS-WMS and its application for emission analysis in Munich / Lijuan Lan ; Gutachter: Jia Chen, Mark Wenig ; Betreuer: Jia Chen“. München : Universitätsbibliothek der TU München, 2020. http://d-nb.info/1212178173/34.
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Chahal, Radwan. „Capteurs optiques en fibres de verre de chalcogénure dopées terres rares appliqués à la surveillance du stockage géologique de CO2“. Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S066/document.
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L'augmentation des émissions de CO2 entraîne un réchauffement de la planète préjudiciable aux équilibres écologiques terrestres. Dans ce contexte, le stockage de CO2 dans des formations géologiques terrestres et sous-marines se pose comme un moyen intéressant de limiter les conséquences de ces émissions. Cependant cette solution nécessite une surveillance continue afin de détecter d'éventuelles fuites au niveau d'une zone de stockage. Les travaux de thèse présentés concernent le développement d'un capteur optique en fibre de chalcogénures pour la détection de CO2 gazeux fonctionnant dans le moyen infrarouge. Cette détection est basée sur un phénomène de luminescence, jouant le rôle de source déportée et partiellement absorbée en présence de CO2. Le développement de ces fibres optiques a demandé un important travail en sciences des matériaux et en caractérisation spectroscopique. Un prototype a été fabriqué et utilisé avec succès sur le terrain lors de campagnes de mesure menées in-situThe increase of CO2 emissions causes global warming harmful to ecological balances in earth. In this context, CO2 storage in geological formations is an interesting way to limit the consequences of these emissions. However, this solution requires continuous monitoring to detect possible leaks at storage area. The presented work involves the development of an optical fiber sensor based on chalcogenide glasses for the CO2 gas detection operating in the infrared. This detection is based on a luminescent phenomenon, acts as a remote source and partly absorbed in the presence of CO2. The development of these fiber optic asked important work in materials science and spectroscopic characterization. A prototype was manufactured and successfully used in the field during measurement campaigns in situ
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Khunou, Ramotseng. „Gas sensing properties of Ceo2 nanostructures“. University of the Western Cape, 2020. http://hdl.handle.net/11394/7909.
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>Magister Scientiae - MScThe industrial safety requirements and environmental pollution have created a high demand to develop gas sensors to monitor combustible and toxic gases. As per specifications of World Health Organization (WHO) and Occupational Safety and Health Administration (OSHA), lengthy exposure to these gases lead to death which can be avoided with early detection. Semiconductor metal oxide (SMO) has been utilized as sensor for several decades. In recent years, there have been extensive investigations of nanoscale semiconductor gas sensor.
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Haensch, Alexander [Verfasser]. „CO2 gas sensors based on rare earth oxycarbonates / Alexander Haensch“. Aachen : Shaker, 2016. http://d-nb.info/111825869X/34.
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Suzuki, Takuya [Verfasser], und Udo [Akademischer Betreuer] Weimar. „Rare-earth based Chemoresistive CO2 Sensors / Takuya Suzuki ; Betreuer: Udo Weimar“. Tübingen : Universitätsbibliothek Tübingen, 2020. http://d-nb.info/1206933836/34.
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Graham, Cathy D. „Chemosensitive Neurons of the Locus Coeruleus and the Nucleus Tractus Solitarius: Three Dimensional Morphology and Association with the Vasculature“. Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1409665728.
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Zhu, Yurong. „A Study of Smart Ventilation System to Balance Indoor Air Quality and Energy Consumption : A case study on Dalarnas Villa“. Thesis, Högskolan Dalarna, Mikrodataanalys, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:du-34431.
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It is a dilemma problem to achieve both these two goals: a) to maintain a best indoor air quality and b) to use a most efficient energy for a house at the same time. One of the outstanding components involving these goals is a smart ventilation system in the house. Smart ventilation strategies, including demand-controlled ventilation (DCV), have been of great interests and some studies believe that DCV strategies have the potential for energy reductions for all ventilation systems. This research aims to improve smart ventilation system, in aspects of energy consumption, indoor CO2 concentrations and living comfortness, by analyzing long-term sensor data. Based on a case study on an experimental house -- Dalarnas Villa, this research investigates how the current two ventilations modes work in the house and improves its ventilation system by developing customized ventilation schedules. A variety of data analysis methods were used in this research. Clustering analysis is used to identify the CO2 patterns and hence determine the residents living patterns; correlation analysis and regression analysis are used to quantify a model to estimate fan energy consumption; a mathematical model is built to simulation the CO2 decreasing when the house is under 0 occupancy. And finally, two customized schedules are created for a typical workday and holiday, respectively, which show advantages in all aspects of energy consumption, CO2 concentrations and living comfortness, compared with the current ventilation modes.
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Kang, Donghyeon. „Control of a hexapod robot equipped with proximity, anemoscope, and CO2 sensors“. Kyoto University, 2008. http://hdl.handle.net/2433/136632.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第13905号
農博第1720号
新制||農||957(附属図書館)
学位論文||H20||N4372(農学部図書室)
UT51-2008-C821
京都大学大学院農学研究科地域環境科学専攻
(主査)教授 梅田 幹雄, 教授 近藤 直, 准教授 中嶋 洋
学位規則第4条第1項該当
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Warburton, P. R. G. „An amperometric sensor for carbon dioxide“. Thesis, University of Southampton, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233047.
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Maxwell, Andrew Douglas. „A CO2 measurement system for low-cost applications using chemical transduction“. University of Southern Queensland, Faculty of Engineering and Surveying, 2002. http://eprints.usq.edu.au/archive/00001468/.
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It is demonstrated that by using a miniature chemical reaction vessel under adaptive mechatronic control, it is possible to design and construct a low-cost carbon dioxide measurement system. With further development such a system would be potentially suitable for low-cost commercial application, in particular as sacrificial, single-mission instrumentation packages in horticultural cargo monitoring. Current instrumentation systems for carbon dioxide (CO2) gas measurement are reviewed and their limitations with respect to low cost commercial applications determined. These utilise technology intended for laboratory measurements. In particular the optical energy absorbance of CO2 in the infra-red electromagnetic spectrum. These systems require large optical paths (typically 10cm) in order to measure small CO2 concentrations. This in turn has a large impact on the physical size of the sensing system. Of the many applications requiring online CO2 sensing packages (such as medical, petroleum, environmental and water treatment)the horticultural industry is the primary focus for this research. CO2 sensing systems are primarily used in horticulture to monitor the produce environment and help extend storage time. For these applications CO2 concentrations are typically low (in the range 0 to 1%) and the paramount need is for low-cost (and possibly disposable) sensing packages. The basis of the measurement technique is the use of bulk (but small volume) aqueous chemical reaction under mechatronic control. Unlike thin film technologies where very thin membranes are passively exposed to the gaseous sample, here a small volume (approximately 2mL) of simple and very cheap liquid chemical indicator (calcium hydroxide solution) is used to produce an opaque precipitate. CO2 concentration is then assessed by low-cost optical attenuation measurements of the developing opacity of the solution. The instrumentation package comprises pumps, flowmeter, reaction cell and infra-red optics for the turbidity measurement, plus reagent and waste vessels, pipelines and electronics. During each measurement cycle, the reaction cell is flushed, with fresh chemical indicator and a sample of gas admitted. The indicator and the sample gas are then vigorously mixed and the change in the indicators optical properties measured at regular intervals. An embedded 8-bit microcontroller performs the necessary analysis to deduce the CO2 concentration (as percentage by volume) for the sample gas by reference to one or more of five ``Time-To-Threshold'' calibration models. These models evaluate the trend in turbidity development as precipitate is formed. First and second prototypes of the measurement system have been constructed and their (low-cost) components and overall performance evaluated, the first a `proof-of-concept' and the second to investigate methodology shortcomings. As a result the design of a third prototype is outlined. The measurement systems have been shown to work adequately well within expected limitations, resulting in a usable low-cost measurement technique. The current prototypes have a useful range of at least 5% to 100% CO2 with a discrimination of typically +-6%. Deficiencies, particularly performance at low concentrations, are identified and potential enhancements for future prototypes proposed.
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Clark, D. „Electrochemical sensors for medical gases“. Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382605.
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Arshad, Fasiha. „A Study of Smart Ventilation System for Maintaining Healthy Living by Optimal Energy Consumption : A case study on Dalarnas Villa“. Thesis, Högskolan Dalarna, Mikrodataanalys, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:du-35967.
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Indoor air quality is a measure of clean air with comfort conditions and depiction of lower concentration of air pollutants. It is tedious task to achieve all quality measures at a time with smart energy consumption. This research aims to come up with a solution of how to improve smart ventilation system in order to get clean indoor air with less consumption of electric energy. Many studies showed that scheduled ventilation system has proven to be a good solution to this problem. For this purpose, a long-term sensor data of smart ventilation system Renson healthbox and Luvians data is studied which is operated in Dalarnas villa. This research investigates how this system works in two modes and to improve it by customized scheduling.A regression model is constructed in which the relationship between airflow and CO2 is shown. For this purpose, correlation analysis is used in which the connection of bonds between each data features are analyzed. After the feature selection, as a result from correlation matrix, regression analysis is used to find out whether the selected features are linearly related or not. Regression analysis also used for the intent to quantify a model to estimate the flowrate and CO2. A mathematical model is also build to simulate the flowrate and CO2 with energy consumption.The results showed that, in order to provide better indoor air quality with efficient energy consumption, a necessary modification of the fan schedule should be done in a way that fan must be started little bit earlier to avoid harmful particles reach their upper threshold limits. This can result in reduction of fan’s maximum speed hence consumption of less energy is achieved.
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Jin, Xin. „Regulation of Ca2+ activated Cl- channel ANO1 (TMEM16A) by different Ca2+ sources in sensory neurons“. Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/9246/.
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Proteins of anoctamin (TMEM16) family are the candidate subunits for Ca2+- activated Cl- channels (CaCC). In recent years, studies have shown that anoctamin-1 (TMEM16A or ANO1) plays important physiological roles in processes including epithelial fluid secretion, muscle contraction and olfactory transduction. How the Ca2+ regulates the activity of ANO1 in different tissue is still not clear. In this study, I showed that the excitatory CaCC in nociceptors (small-diameter sensory neurons that are responsible for transmission of painful stimuli) was activated by the release of Ca2+ from the 1, 4, 5-trisphosphate (IP3)-sensitive intracellular stores in response to bradykinin (BK) or proteases (through protease activated receptor 2). Interestingly, while in the majority of nociceptors, CaCC was induced by Ca2+ release from the stores, only in a few neurons CaCC was activated by the Ca2+ influx through the voltage-gated Ca2+ channels (VGCC). Chelating intracellular Ca2+ with the slow Ca2+ buffer EGTA did not affect CaCC activation by protease activated receptor 2 (PAR2), while BAPTA abolished such activation, suggesting a close proximity of the Ca2+ release sites and CaCC. Membrane fractionation demonstrated that in the dorsal root ganglion (DRG), ANO1, bradykinin receptor 2 (B2R) or PAR2, were co-purified with lipid raft marker caveolin-1. Using various biochemical approaches I further demonstrated that ANO1 physically interacted with the IP3 receptor 1 (IP3R1) in DRG. Moreover, IP3R1, ANO1, B2R, and/or PAR2 were all assembled into functional signalling complexes and the plasma membrane components of the complex which contained ANO1 and GPCRs were tethered to the juxtamembrane regions of the endoplasmic reticulum. Disruption of the membrane microdomains by methyl-beta-cyclodextrin (MβCD) or competitive peptides partially restored coupling of CaCC to VGCC but disrupted coupling between B2R or PAR2 signaling and ANO1. Thus, such molecular complexes dichotomize different Ca2+ sources to provide ANO1-mediated excitation in response to specific ambient signals but protect the channels from global changes in intracellular Ca2+ and prevent sensory neurons from overexcitability.
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Sánchez-Cañete, Enrique P., Russell L. Scott, Haren Joost van und Greg A. Barron-Gafford. „Improving the accuracy of the gradient method for determining soil carbon dioxide efflux“. AMER GEOPHYSICAL UNION, 2017. http://hdl.handle.net/10150/623105.
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Soil CO2 efflux (F-soil) represents a significant source of ecosystem CO2 emissions that is rarely quantified with high-temporal-resolution data in carbon flux studies. F-soil estimates can be obtained by the low-cost gradient method (GM), but the utility of the method is hindered by uncertainties in the application of published models for the diffusion coefficient. Therefore, to address and resolve these uncertainties, we compared F-soil measured by 2 soil CO2 efflux chambers and F-soil estimated by 16 gas transport models using the GM across 1year. We used 14 published empirical gas diffusion models and 2 in situ models: (1) a gas transfer model called Chamber model obtained using a calibration between the chamber and the gradient method and (2) a diffusion model called SF6 model obtained through an interwell conservative tracer experiment. Most of the published models using the GM underestimated cumulative annual F-soil by 55% to 361%, while the Chamber model closely approximated cumulative F-soil (0.6% error). Surprisingly, the SF6 model combined with the GM underestimated F-soil by 32%. Differences between in situ models could stem from the Chamber model implicitly accounting for production of soil CO2, while the conservative tracer model does not. Therefore, we recommend using the GM only after calibration with chamber measurements to generate reliable long-term ecosystem F-soil measurements. Accurate estimates of F-soil will improve our understanding of soil respiration's contribution to ecosystem fluxes.
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Huo, Wei. „Controlled Fabrication System of Fabry-Perot Optical Fiber Sensors“. Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/10033.
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The use of optical fiber sensors is increasing widely in industry, civil, medicine, defense and research. Among different categories of these sensors is the Extrinsic Fabry-Perot interferometer (EFPI) sensor which is inherently simple and requires only modest amount of interface electronics. These advantages make it suitable for many practical applications. Investigating a cost-effective, reliable and repeatable method for optical fiber sensor fabrication is challenging work. In this thesis, a system for controlled fabrication of Fabry-Perot optical fiber sensors is developed and presented as the first attempt for the long-term goal of automated EFPI sensor fabrication. The sensor fabrication control system presented here implements a real-time control of a carbon dioxide (CO₂) laser as sensor bonding power, an optical fiber white light interferometric subsystem for real-time monitoring and measurement of the air gap separation in the Fabry-Perot sensor probe, and real-time control of a piezoelectric (PZT) motion subsystem for sensor alignment. The design of optoelectronic hardware and computer software is included. A large number of sensors are fabricated using this system and are tested under high temperature and high pressure. This system as a prototype system shows the potential in automated sensor fabrication.Master of Science
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Wilzewski, Jonas S. [Verfasser], und Bernhard [Akademischer Betreuer] Mayer. „Towards CO2 emission monitoring with passive air- and space-borne sensors / Jonas S. Wilzewski ; Betreuer: Bernhard Mayer“. München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2021. http://d-nb.info/1238017126/34.
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Santos, Camila Paixão [UNESP]. „Fabricação e caracterização de filmes espessos de CeO2 puro para aplicação em sensores de gás“. Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/144639.
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Este trabalho apresenta e discute o uso do óxido de cério na fabricação de filmes espessos por “screen printing” para aplicações em sensores de gás. Nesse estudo o CeO2 puro foi obtido pelo método dos precursores poliméricos utilizando como resina precursora o citrato de céria. O “puff” – espuma resultante da primeira fase do tratamento térmico da resina- foi calcinado a 550, 600, 700 e 750°C. O pó foi caracterizado por termogravimetria (TG) e as propriedades estruturais, morfológicas foram avaliadas por difratometria de raios X (DRX), espectroscopia Raman, área de superfície por isotermas Brunauer, Emmett e Taller (BET) e microscopia eletrônica de varredura (MEV). A resposta sensora foi estudada em uma câmara de teste construída no Laboratório de Catálise e Superfícies do Instituto de Ciência de Tecnologia de Materiais (INTEMA) da Universidade de Mar del Plata. A TG mostrou a formação de óxido de cério a 550°C, temperatura relativamente baixa quando comparada com outros métodos. Mediante DRX todas as amostras mostraram picos correspondentes à fase pura de CeO2 o qual cristaliza em uma estrutura cúbica do tipo fluorita, entretanto, maiores temperaturas de calcinação mostraram aumento da cristalinidade e tamanho do cristalito. No espectro Raman, um forte pico em torno do 461 cm-1 foi detectado, atribuído às vibrações simétricas do Ce-O. A área de superfície BET dos pós foi de 301, 77 m2/g o que evidencia a formação de partículas muito pequenas e altamente reativas. As micrografias obtidas por MEV mostram a presença de diferentes tamanhos na forma de aglomerados. A caracterização da resposta sensora mostrou que o sensor fabricado a partir de pós de CeO2 puro apresenta um bom tempo de resposta, alcançando a melhor performance com temperatura de trabalho de 400 °C, tanto em atmosferas redutoras e oxidantes. A característica principal observada foi que os resultados são dependentes dos ciclos anteriores, a reprodutibilidade do sistema é garantida quando se apaga a “memória” do sistema, expondo-o ao vácuo.
This paper presents and discusses the use of cerium oxide in the production of thick films for "screen printing" for applications in gas sensors. In this study the pure CeO2 was obtained by the polymeric precursor method using as a precursor resin citrate ceria. The "puff" - resulting foam from the first stage of thermal treatment of the resin-calcined at 550, 600, 700 and 750 °C. The powder was characterized by thermogravimetry (TG) and structural, morphological were evaluated by X-ray diffraction (XRD), Raman spectroscopy, isothermal Brunauer surface area, Emmett and Taller (BET) and scanning electron microscopy (SEM) . The sensor response was studied in a test chamber built in the Laboratory of Catalysis and Surface Materials Technology Institute of Science (INTEMA), University of Mar del Plata. The thermogravimetry showed the formation of cerium oxide at 550° C, relatively low temperature compared with other methods. Upon XRD all samples showed peaks corresponding to pure CeO2 phase which crystallizes in a cubic fluorite type structure, however, higher calcination temperatures showed increased crystallinity and crystallite size. In the Raman spectrum, a strong peak around 461 cm-1 was detected, assigned to symmetric vibrations of the Ce-O. The BET surface area of the powders was 301, 77 m2 /g which shows the formation of very small and highly reactive particles. The SEM micrographs show the presence of different sizes in the form of agglomerates. The characterization of the sensor response showed that the sensors manufactured from pure CeO2 powder has a good response time, achieving better performance at 400 °C working temperature in both reducing and oxidizing atmospheres. The main feature observed was that the results are dependent on previous cycles, the system reproducibility is guaranteed when it deletes the "memory" of the system, exposing it to vacuum.
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Hwang, Ji-Young. „Biochemical and biophysical studies on guanylate cyclase activating protein 1, a Ca2+-sensor in Phototransduction“. [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=962777412.
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Nunes, Bruno Rios Patriarca. „Maximum lifetime broadcast problem in wireless sensor networks“. Escola Politécnica / Instituto de Matemática, 2013. http://repositorio.ufba.br/ri/handle/ri/21338.
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Redes de sensores sem o (RSSF) são compostas por um conjunto de dispositivos, geralmente de baixa capacidade de processamento e autonomia de energia limitada, com o objeto de coletar dados sobre a area onde foi instalada e envia-los ate as unidades de processamento chamadas de estações base. Dentre os recursos de um no sensor, pode-se considerar como um dos mais críticos a carga de bateria, ja que ela de ne em ultimo caso o tempo de vida util do no. Por conta disso, e necessario que os protocolos e aplicações otimizem o uso de energia a m de prolongar o tempo de vida do no sensor e, consequentemente, de toda a RSSF.Este trabalho dedica-se a estudar o problema da maximiza¸c˜ao do tempo de vida da rede durante uma s´erie de opera¸c˜oes de broadcast. Para o escopo desta pesquisa, o tempo de vida da rede de sensor ´e definido como o tempo at´e a falha do primeiro n´o por falta de energia. H´a diversos protocolos na literatura que buscam minimizar o consumo de energia durante a dissemina¸c˜ao de mensagens na rede, por´em neles n˜ao s˜ao considerados aspectos como o custo de recep¸c˜ao ou a presen¸ca de links assim´etricos entre os n´os. Neste trabalho, propomos o algoritmo DLMCA para o problema de maximiza¸c˜ao do tempo de vida da rede. O algoritmo DLMCA baseia-se na constru¸c˜ao de arborescˆencias de custo m´ınimo, ´e localizado e considera redes com custos de comunica¸c˜ao assim´etricos, o que ´e especialmente importante em casos em que a RSSF ´e composta por dispositivos diferentes. Os experimentos realizados mostraram que o DLMCA ´e mais eficiente que solu¸c˜oes alternativas propostas na literatura. A heur´ısitca oferecida pelo DLMCA para redes est´aticas foi levemente adaptada e o problema tamb´em foi analisado para redes m´oveis. Para estas redes, os experimentos demonstraram que a solu¸c˜ao baseada no DLMCA tamb´em foi superior em rela¸c˜ao a outras propostas tanto em rela¸c˜ao `a energia total gasta em cada operação de broadcast quanto em relação ao tempo de vida da rede.
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Kim, Man Su. „Regulatory mechanisms of the Ca2+-dependent transcription factor NFAT in sensory neurons“. Diss., University of Iowa, 2009. https://ir.uiowa.edu/etd/832.
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Ca2+-mediated regulation of gene expression plays an important role in neuronal plasticity. NFAT (Nuclear Factor of Activated T-cells) is a Ca2+/calcineurin (CaN)-dependent transcription factor that has been implicated in a number of neuronal functions including axon outgrowth, presynaptic remodeling and neural survival. NFAT is activated by Ca2+/CaN-dependent dephosphorylation, whereas re-phosphorylation by glycogen synthase kinase-3β (GSK3β) and several other protein kinases deactivates NFAT and triggers its export from the nucleus. In addition to electrically-mediated Ca2+ signals, neurotrophins can potently regulate NFAT function in neurons as well. However the mechanisms of NFAT activation by electrical activity and neurotrophins are not completely understood.
In aim 1, I found that electrical stimulation produced a mitochondrial Ca2+ cycling-mediated prolonged [Ca2+]i elevation (plateau), which profoundly affected NFAT activity. The elimination of the [Ca2+]i plateau by blocking mitochondrial Ca2+ uptake or release strongly reduced nuclear import of NFAT. Furthermore, preventing Ca2+ mobilization from mitochondria diminished NFAT-mediated transcription. In aim 2, I found that NGF, a family of neurotrophins, potentiated NFAT-dependent transcription triggered by electrical activity through the TrkA-PI3K-Akt-GSK3β pathway and this effect was mediated primarily by NFATc3. Monitoring NFATc3 movement in DRG neurons in real time showed that NGF slowed the rate of NFATc3 nuclear export, which was mimicked by inhibiting GSK3β, whereas blockade of PI3K prevented this effect. Taken together, I proposed that mitochondrial Ca2+ cycling functions as a novel regulatory mechanism for NFAT activation and NFATc3 serves as an integrator of electrical activity and neurotrophin signaling in the regulation of gene expression in DRG neurons.
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Talley, Sharon. „A Sensory Tour of Cape Cod: Thoreau's Transcendental Journey to Spiritual Renewal“. Thesis, University of North Texas, 1999. https://digital.library.unt.edu/ark:/67531/metadc2264/.
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Predominantly darker than his other works, Cape Cod depicts Henry David Thoreau's interpretation of life as a struggle for survival and a search for salvation in a stark New England setting. Representing Thoreau's greatest test of the goodness of God and nature, the book illustrates the centrality of the subject of death to Thoreau's philosophy of life. Contending that Thoreau's journey to the Cape originated from an intensely personal transcendental impulse connected with his brother's death, this study provides the first in-depth examination of Thoreau's use of the five senses in Cape Cod to reveal both the eccentricities inherent in his relationship with nature and his method of resolving his fears of mortality. Some of the sense impressions in Cape Cod--particularly those that center around human death and those that involve tactile sensations--suggest that Thoreau sometimes tried to master his fears by subconsciously altering painful historical facts or by avoiding the type of sensual contact that aggravated the repressed guilt he suffered from his brother's death. Despite his personal idiosyncrasies, however, Thoreau persisted in his search for truth, and the written record of his journey in Cape Cod documents how his dedication to the transcendental process enabled him to surmount his inner turmoil and reconfirm his intuitive faith. In following this process to spiritual renewal, Thoreau begins with subjective impressions of nature and advances to knowledge of objective realities before ultimately reaching symbolic and universal truth. By analyzing nature's lessons as they evolve from Thoreau's use of his senses, this dissertation shows that Cape Cod, rather than invalidating Thoreau's faith, actually expands his transcendental perspective and so rightfully stands beside Walden as one of the fundamental cornerstones of his canon. In addition, the study proffers new support for previous psychoanalytical interpretations of Thoreau and his writings, reveals heretofore unrecognized historical inaccuracies in his account of the shipwreck that frames the book's opening, and provides the first detailed consideration of the linguistic implications of Cape Cod.
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El, Younsi Imane. „Elaboration et caractérisation de nouvelles couches sensibles pour la réalisation de capteurs de CO2“. Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30344/document.
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La mesure du taux de CO2 est un besoin relativement récent. Les travaux sur l'utilisation de nouveaux matériaux pour la réalisation de capteurs de gaz, efficaces et peu chers, suscitent des intérêts scientifique et technologique croissants. L'objectif de ces travaux de thèse est l'élaboration et la caractérisation de nouvelles couches sensibles obtenues par pulvérisation cathodique radiofréquence pour la réalisation de capteurs de CO2. Les films minces ont été déposés à partir d'une cible céramique de CuO, dans diverses conditions de dépôt, en variant la pression d'argon dans l'enceinte et la puissance RF appliquée. Dans un premier temps, nous avons caractérisé la structure et la microstructure des films bruts et recuits sous air par DRX, MEB, AFM et spectroscopie Raman. Nous avons également étudié les propriétés physiques des films minces ainsi que leur surface accessible par adsorption de gaz krypton (méthode de Brunauer, Emmett et Teller). Le traitement thermique à 450°C n'affecte pas la structure cristalline des couches, en revanche il tend à faire chuter fortement la surface accessible entre les colonnes. Après l'optimisation des paramètres de fonctionnement de la cellule de mesure, nous avons caractérisé les performances des films de CuO pour la détection du CO2. La meilleure réponse (?R/R=51 %) a été obtenue pour une couche élaborée à 2 Pa avec une puissance RF de 30W. De plus, la température optimale de mesure est relativement basse (T= 250°C). Le contrôle de la microstructure et plus particulièrement de la taille des grains s'est avéré être le paramètre principal qui impacte la réponse sous CO2. Les meilleurs résultats ont été obtenus avec des tailles de grains proches d'une vingtaine de nanomètres de diamètre. Une bonne modélisation de la réponse électrique en fonction de la taille des grains a pu être réalisée en prenant en compte un circuit électrique équivalent comportant une zone enrichie en porteur de type trous à la surface des grains et dont l'épaisseur est de l'ordre de la longueur de DebyeThe measure of the rate of CO2 is a recent need. The works on the use of new materials for the conception of gas sensors based semiconductor oxides, effective and not expensive; arouse a huge interest in our society. The objective of this thesis is the elaboration and the characterization of new sensitive layers obtained by RF sputtering for the realization of the sensors of CO2. Thin films were deposited using two targets: CuFeO2 and CuO, under three conditions by varying argon pressure and RF power. First of all, the structure and the microstructure were studied for the as-deposited samples. Surface investigations carried out by Atomic Force Microscopy (AFM), X-ray Diffraction (XRD), Raman spectroscopy, BET measurements and MEB-FEG images have shown a strong influence of deposition technique parameters on film surface topography and morphology. In a second step, the thin films were annealed in air in order to oxidize the phase. For the composite CuO/CuFe2O4, Glow discharge optical emission spectrometry technique showed a structure in two layers stacked on top of each other for the thinner films. For the cupric films, no changes on both structure and microstructure have been revealed. Our films have then been evaluated for CO2 detection. The sensitive layers with different thicknesses were sensitive to 5000 ppm of CO2. The deposition parameters are optimized to obtain microstructure features which can enhance the sensitivity of the thin films as gas sensors. Best response was obtained for a cupric sample deposited in P2 30W conditions and was close to 50% at T = 250°C. We have demonstrates that cupric oxide alone can detect the CO2 gas and that the growth conditions determine the film surface characteristics. The gas sensing characteristics of these films are strongly influenced by both surface morphology and microstructure
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Sutton, Kathy Gayle. „Action of polyamine and polypeptide toxins CA2+channel and CA2+-dependent chloride currents from rat central and sensory neurones in culture“. Thesis, St George's, University of London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265354.
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Menghini, Massimiliano. „Sviluppo e sperimentazione di sensori per il monitoraggio della qualità dell'aria“. Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10249/.
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Individuare e conoscere la natura degli inquinanti atmosferici e disporre dei dati delle emissioni sono azioni fondamentali per formulare politiche ambientali incentrate sul miglioramento della qualità dell'aria e monitorarne l'efficacia. Sorge l'esigenza di un controllo costante della qualità dell'aria, processo che avviene utilizzando delle centraline di monitoraggio fisse sparse nelle vie delle maggiori città o nei pressi dei principali insediamenti industriali.
Lo scopo di questo progetto è quello di realizzare una stazione di monitoraggio mobile al fine di aumentare la superficie di controllo, realizzando un oggetto dinamico capace di acquisire dati sull'inquinamento. Questo è stato fatto applicando ad un drone un sistema di sensori capaci di rilevare le variazioni dei livelli di concentrazione degli agenti inquinanti. Ciò permette di eliminare le stazioni di monitoraggio fisse, le quali rappresentano una spesa ingente. Inoltre, attraverso l'utilizzo di un drone, è possibile monitorare siti più vasti, permettendo un monitoraggio costante e ripetuto nel tempo.
La prima parte dell'elaborato analizza il sistema Embedded utilizzato per l'acquisizione dei dati, concentrando l'attenzione prevalentemente sui moduli utilizzati.
La seconda descrive quali sono i primi passi per cominciare ad utilizzare i sensori posti sulla Gases Board 2.0 e risponde ai dubbi più comuni su quali parametri di configurazione adottare per un avere una risposta adeguata, quale processo di calibrazione seguire o come trasformare i dati acquisiti, espressi in tensioni, in valori di concentrazione di gas.
La terza parte illustra i test effettuati per verificare il corretto funzionamento del sistema completo, con l’esposizione delle problematiche individuate, e una presentazione delle alternative più valide per superarle.
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Králová, Petra. „Přídavek oxidu uhličitého do mléka pro výrobu sýrů“. Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-216613.
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This work deals with the addition of carbon dioxide to milk for cheese production. The first aim was to elaborate a literary search focused on chemical composition of milk and its changes after addition of carbon dioxide and to describe production processes, with or without addition of carbon dioxide. The opening part was in particular focused on production of cheese with carbon dioxide and what all this gas causes during production. Carbon dioxide significantly decreases pH, thereby preventing from multiplication of undesirable microorganisms, it is also very important for shortening of production time, because it shortens the coagulation time. The main aim of experimental part was to determine the optimum addition of carbon dioxide to milk for production of Balkan cheese and using several analytical methods to compare cheese produced with and without addition of carbon dioxide. The sensory methods suitable for following of sensory differences of produced cheeses were also chosen and applied. By request of Dairy in Polná Ltd., the operation economy was calculated, which revealed that production with carbon dioxide is very useful and can reduce production costs of Balkan cheese, which would certainly be positive. The advantages and disadvantages of cheese production with carbon dioxide for consumers as well as for producer are evaluated as conclusion of this work.
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Photinon, Kanokorn. „DEVELOPMENT OF DIMETHYL ETHER (DME) AND CARBON DIOXIDE SENSORS USING PLATINUM NANOPARTICLES AND THICK FILM TECHNOLOGY“. Case Western Reserve University School of Graduate Studies / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=case1164899809.
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Pahlke, Denis. „Synthesis, characterisation and sensor-functionalisation of transmembrane β-peptides“. Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://hdl.handle.net/21.11130/00-1735-0000-0003-C180-1.
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Bahi-Buisson, Nadia. „Etude des mécanismes pathogéniques du retard mental lié aux mutations dans IL-1 Receptor Accessory Protein Like IL1RAPL“. Paris 6, 2005. http://www.theses.fr/2005PA066079.
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Puccio, Derek. „DESIGN, ANALYSIS AND IMPLEMENTATION OF ORTHOGONAL FREQUENCY CODING IN SAW DEVICES USED FOR SPREAD SPECTRUM TAGS AND SENSORS“. Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2836.
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SAW based sensors can offer wireless, passive operation in numerous environments and various device embodiments are employed for retrieval of the sensed data information. Single sensor systems can typically use a single carrier frequency and a simple device embodiment, since tagging is not required. In a multi-sensor environment, it is necessary to both identify the sensor and retrieve the sensed information. This dissertation presents the concept of orthogonal frequency coding (OFC) for applications to SAW sensor technology. OFC offers all advantages inherent to spread spectrum communications including enhanced processing gain and lower interrogation power spectral density (PSD). It is shown that the time ambiguity in the OFC compressed pulse is significantly reduced as compared with a single frequency tag having the same code length and additional coding can be added using a pseudo-noise (PN) sequence. The OFC approach is general and should be applicable to many differing SAW sensors for temperature, pressure, liquid, gases, etc. Device embodiments are shown and a potential transceiver is described. Measured device results are presented and compared with COM model predictions to demonstrate performance. Devices are then used in computer simulations of the proposed transceiver design and the results of an OFC sensor system are discussed.Ph.D.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering
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Huang, Yun. „Integration of Extracellular and Intracellular Calcium Signals: Roles of Calcium-Sensing Receptor (CASR), Calmodulin and Stromal Interaction Molecule 1 (STIM1)“. Atlanta, Ga. : Georgia State University, 2008. http://digitalarchive.gsu.edu/chemistry_diss/28/.
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Thesis (Ph. D.)--Georgia State University, 2008.Title from title page (Digital Archive@GSU, viewed July 1, 2010) Jenny J. Yang, committee chair; Edward Brown, Giovanni Gadda, Zhi-ren Liu, committee members. Includes bibliographical references (p. 230-258).
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Todd, Paul Anthony Christopher. „Characterisation of the Ca2+ signaling pathway involved in the control of temperature dependent locomotion by Neuronal Calcium Sensor-1 in Caenorhabditis elegans“. Thesis, University of Liverpool, 2017. http://livrepository.liverpool.ac.uk/3005922/.
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Calcium (Ca2+) signaling is critical in regulating a number of neuronal functions including synaptic transmission, axonal growth, development and neurotransmitter release/recycling. The EF-hand containing Ca2+ binding protein Neuronal Ca2+ Sensor 1 (NCS-1) has been shown to be important in a number of these processes. NCS-1 is a member of the NCS family of proteins encoded in mammals by 14 genes. Ca2+ bound NCS-1 exposes a hydrophobic binding domain through an altered conformation allowing regulation of downstream processes, dependent on a diverse range of target proteins. Many interacting partners have been identified for NCS-1, some of which are common to Calmodulin (CaM) with others unique to NCS-1. Mammalian NCS-1 has been shown to regulate PQ-type voltage-gated Ca2+ channels (VGCCs), although evidence of a direct interaction between the two proteins has been lacking. The initial part of this study investigated interactions between NCS-1 and PQ-type VGCCs (CaV2.1). Within the CaV2.1 C-terminal tail, there are two Ca2+-sensor binding regions; the CBD (CaM binding domain) and the IM/IQ domain. Through cell transfection and fluorescence based experiments, an interaction between these two proteins was established. Co-expression of NCS-1 and a PQ channel C-terminal domain led to the appearance of hallmark aggregated cellular structures. Furthermore, the kinetic behaviour of NCS-1 and PQ in these cells was significantly different to those observed when each protein was expressed in isolation. The second part of this study used C. elegans as a model organism to study in vivo interactions of NCS-1. In C. elegans NCS-1 is primarily found in the nervous system, with highest expression in sensory neurons. Previous studies have identified a defect in isothermal tracking in an ncs-1 defective C. elegans animal. When tested in a locomotion assay, characterised in this thesis, the locomotion rate of wild-type C. elegans decreased at an elevated temperature of 28oC whilst the ncs-1 null C. elegans showed a slight yet significant increase in locomotion at the elevated temperature. During this project a reversible paralysis phenotype was identified in the temperature dependent locomotion assay (TDLA). In the second part of the project this assay was exploited to quantify the paralysis phenotype in various mutant C. elegans strains. Based on the mammalian NCS-1 interactome, a sub-set of protein orthologues were identified within the C. elegans nervous system as potential interacting proteins to be studied. It was established that potential targets were TRP1 & 2, ARF-1.1 and PI4K of which various double mutants were generated through C. elegans genetic crosses. The double mutants identified a genetic interaction between ARF-1.1 and NCS-1 in the TDLA suggestive of a possible functional interaction. Additional studies using a chemical inhibitor of phosphatidylinositol 4kinaseIIIb suggests a potential network comprising PI4K-1, NCS-1 and ARF-1.1 regulates this behaviour. These findings allowed a partial elucidation of the interactions and functional relationships between these proteins in a physiological context with an identifiable behavioural output.
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Pinilla, Pachon Edwin German 1981. „Dispositivos em fibras ópticas baseados em interferência multimodal“. [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/277582.
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Orientadores: Cristiano Monteiro de Barros Cordeiro, Marcos Antonio Ruggieri FrancoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin
Made available in DSpace on 2018-08-22T12:56:38Z (GMT). No. of bitstreams: 1 PinillaPachon_EdwinGerman_M.pdf: 12541930 bytes, checksum: 74a0367c344ded9c8891d11280568b6b (MD5) Previous issue date: 2013
Resumo: Nesta dissertação se estudou por simulação numérica o efeito de interferência multimodal (MMI, do inglês "multimode interference") em guias de onda, com atenção especial a fibras ópticas, e a resposta óptica do dispositivo MMI a parâmetros externos como temperatura, curvatura e índice de refração. Dispositivos baseados em MMI são formados, em geral, por três guias de onda concatenados sendo as extremidades compostas de guias monomodo e a parte central composta de um guia que permite a propagação de muitos modos, tipicamente, mais do que três. Nesta situação, na seção multimodo, são formadas reimagens que aproximadamente replicam fase e amplitude do campo óptico de entrada. A observação do espectro de transmissão correspondente à primeira reimagem, em dispositivos MMI, permite desenvolver sensores de índice de refração, temperatura e curvatura. A sensibilidade dos sensores foi avaliada frente às variações do mensurando, ou seja, variações no índice de refração, temperatura e curvatura da estrutura MMI em fibra óptica.
Abstract: In this work the effect of multimodal interference (MMI) in waveguides was studied by numerical simulation. Special attention was given to optical fibers and its the optical response when external parameters such as temperature, curvature or refractive índex were varied. MMI devices are usually formed by connecting three waveguides being the input and output ones single mode waveguides while the middle one is a waveguide that allows the propagation of many optical modes, typically more than three. In this situation re-images that replicate both the phase and the amplitude of the input optical field are formed periodically within the multimode section. The analysis of the transmission spectrum of the first re-image in MMI devices were realized in order to get information about the fiber environment, in particular the surrounding refractive índex, radius of curvature and temperature. The sensors sensitivity was evaluated.
Mestrado
Física
Mestre em Física
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Golden, Melissa Lynn. „The bioinorganic chemistry of N2S2 metal complexes: reactivity and ligating ability“. Diss., Texas A&M University, 2002. http://hdl.handle.net/1969.1/2198.
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[N,N??-bis-(mercaptoethyl)-1,5-diazacyclooctanato]NiII, Ni-1, is known to undergo metallation reactions with numerous metals. [N,N??-bis-(mercaptoethyl)-1,5-diazacycloheptanato]NiII, (bme-dach)Ni or Ni-1??, differs from Ni-1 by one less carbon in its diazacycle backbone ring producing subtle differences in N2S2Ni geometry. Metallation of Ni-1?? with PdCl2, Pd(NO3)2, and NiBr2 produced three structural forms: Ni2Pd basket, Ni4Pd2 C4-paddlewheel, and Ni3 slant chair. In attempts to provide a rationale for the heterogeneity in the active site of Acetyl coA Synthase, metal ion capture studies of Ni-1 in methanol found a qualitative ranking of metal ion preference: Zn2+ < Ni2+ < Cu+. Formation constants for metal ion capture of Ni-1?? in water were determined for Pb2+, Ni2+, Zn2+, Cu+, and Ag+. A quantitative estimate places copper some 15 orders of magnitude above nickel or zinc in binding affinity. Sulfur dioxide uptake by Ni-1?? is characterized by significant color change, improved adduct solubility, and reversible binding of two equivalents of SO2. These combined properties establish Ni-1?? as a suitable model for gas uptake at nickel thiolate sites and as a possibly useful chemical sensor for this poisonous gas. Comparisons of molecular structures, ν(SO) stretching frequencies, and thermal gravimetric analyses are made to reported adducts including the diazacyclooctane derivative, Ni-1·2SO2. Visual SO2 detection limits of Ni-1 and Ni-1?? are established at 25 ppm and 100 ppm, respectively. Structural studies of products resulting from reaction at the nucleophilic S-sites of (bme-dach)Ni and [(bme-dach)Zn]2 included acetyl chloride and sodium iodoacetate as electrophiles are shown. The acetyl group is a natural electrophile important to the citric acid cycle. Acetylation of (bme-dach)Ni produces a five coordinate, paramagnetic species. Iodoacetate is a cysteine modification agent known to inhibit enzymatic activity. The reaction of (bme-dach)Ni and sodium iodoacetate yields a blue, six coordinate nickel complex in a N2S2O2 donor environment. The bismercaptodiazacycloheptane ligand binds lead(II) forming an unprecedented structural form of N2S2M dimers, in which Pb2+ is largely bound to sulfur in a highly distorted trigonal geometry. Its unusual structure is described in comparison to other derivatives of the bme-daco ligand. The synthesis and structural characterization of square pyramidal (bme-dach)GaCl are also given and compared to the analogous (bme-daco)GaCl.