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Dissertations / Theses on the topic 'IOX'

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Published: 10 December 2022

Last updated: 28 January 2023

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Behnen, Ulrich J. [Verfasser], Klaus [Akademischer Betreuer] Mainzer, Christoph [Gutachter] Lütge, and Klaus [Gutachter] Mainzer. "Ontologie komplexer IoX-Systeme : Zur Metaphysik der Informatik im Internet of Everything / Ulrich J. Behnen ; Gutachter: Christoph Lütge, Klaus Mainzer ; Betreuer: Klaus Mainzer." München : Universitätsbibliothek der TU München, 2018. http://d-nb.info/1169825613/34.

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Behnen, Ulrich J. Verfasser], Klaus [Akademischer Betreuer] [Mainzer, Christoph [Gutachter] Lütge, and Klaus [Gutachter] Mainzer. "Ontologie komplexer IoX-Systeme : Zur Metaphysik der Informatik im Internet of Everything / Ulrich J. Behnen ; Gutachter: Christoph Lütge, Klaus Mainzer ; Betreuer: Klaus Mainzer." München : Universitätsbibliothek der TU München, 2018. http://nbn-resolving.de/urn:nbn:de:bvb:91-diss-20181002-1440052-1-3.

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Ahlström, Margareta. "Hörselskadade barn i kommunikation och samspel /." Stockholm : Univ, 2000. http://www.lhs.se/iol/publikationer/.

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Engdahl, Ingrid. "Med barnens röst : ettåringar "berättar" om sin förskola /." Stockholm : Institutionen för individ, omvärld och lärande, Lärarhögskolan i Stockholm, 2007. http://www.lhs.se/iol/publikationer/.

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O'Malley, Matthew J. "Li⁺/H⁺ Ion-exchanged Li₂MO₃ (M = Ir, Pt) and carbonate melt oxidized IrOx pH sensors." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1221839212.

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Hughes, Ian G. "Electron ion and ion-ion collisions." Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335410.

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Marinetti, Andrea. "Recovery of Carboxylic acids from anaerobic fermented broth through ionic exchange processes." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.

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The recovery of Carboxylic acids were based on two particular objective: the study of the efficiency of a cation exchange resin, used in order to reduce the pH of the actual effluent, considering it is necessary to have a low pH for the anion exchange resin to be able to adsorb the acids from the effluent, and the preliminary studies perfomerd on the anion exchange resin, at various flow rates and both mode of operation, expanded and packed bed mode, using a simulated effluent, were the carboxylic acids were represented by just acetic acid, as the target molecule.

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Westberg, Anna. "Scoutskjortan : mer än ett klädesplagg /." Stockholm : Lärarhögsk, 2004. http://www.lhs.se/iol/publikationer/IOLrapport_pdf/IOL.Forskning24.pdf.

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Ljunggren, Anette. "Effekter av EDI i interorganisatoriska relationer." Thesis, University of Skövde, Department of Computer Science, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-435.

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EDI står för elektroniskt utbyte av data från dator till dator och sker mellan kända affärspartners. När EDI införs i en relation mellan två organisationer anses relationen bli mer komplex än tidigare. Syftet med detta arbete är därför att undersöka hur EDI påverkar interorganisatoriska relationer.

Undersökningen utförs genom att studera affärsrelationerna mellan en offentlig förvaltning och tre av dess leverantörer. I dessa relationer studeras speciellt hur förhandlingsstyrkan, flexibiliteten och tillförlitligheten har påverkats av att EDI har börjat användas för den offentliga förvaltningens inköpsprocess.

De slutsatser som dras är att de undersökta faktorerna förändras i takt med att EDI blir alltmer integrerat i affärsrelationerna. Initialt byggs vissa omställningskostnader upp, som ökar leverantörernas förhandlingsstyrka. När EDI-kommunikationen fungerar kan kunden komma att öka sin förhandlingsstyrka på grund av bättre informationsdelning och något större inköpsvolymer hos leverantören. Flexibiliteten har ännu inte förändrats nämnvärt, medan tillförlitligheten i leveranserna har ökat till följd av EDI.

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Schumann, Matthew Thomas. "The effect of ion-orbit-loss on the distribution of ion, energy and momentum from the edge plasma into the scrape-off layer in tokamaks." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53519.

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Some of the outflowing ions in the plasma edge have sufficient energy to access orbits which allow them to free-stream out of the confined plasma region and be lost to the wall or divertor. The effects of this ion-orbit-loss (IOL) on the poloidal distribution of ion, energy and momentum fluxes from the plasma edge into the tokamak scrape-off layer (SOL) are analyzed for a representative DIII-D H-mode discharge. IOL yields large fluxes of particle, energy and momentum, distributed poloidally over the SOL, but predominantly into the outboard SOL, significantly changing the fluxes due to transport processes for confined ions within the edge plasma. An intrinsic co-current rotation in the edge of the plasma is produced by the preferential loss of counter-current ions

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Isildak, Ibrahim. "Ion selective electrodes in ion chromatography." Thesis, University of Newcastle Upon Tyne, 1992. http://hdl.handle.net/10443/859.

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The number of applications of potentiometric detection In Ion chromatography Is Increasing In the use of ion selective electrodes for which the response Is not limited to a few number of Ions. In this research, membrane electrodes, for a number of Ions, based on PVC were prepared to examine selectivity, detection limit and reproducibility for chromatographic and flow-injection measurements via mixed solution method and flow-injection technique. The selectivity sequence of anion selective electrodes for single charged Inorganic anions was F< Cl < Br < NO 2< NO 3

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Adelhelm, Philipp. "From Lithium-Ion to Sodium-Ion Batteries." Diffusion fundamentals 21 (2014) 5, S.1, 2014. https://ul.qucosa.de/id/qucosa%3A32397.

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Hagos, Fitsum. "Poverty, institutions, peasant behavior and conservation effort in Northern Ethiopia." [Ås, Norway] : Norges landbrukshøgskole, 2003. http://www.nlh.no/ios/Publikasjoner/avhandling/a2003-2.pdf.

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Kielpinski, David. "Entanglement and decoherence in a trapped-ion quantum register." [Boulder, Colo. : University of Colorado], 2001. http://www.boulder.nist.gov/timefreq/ion/qucomp/papers/dkthesis/dkthesis.pdf.

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Tikabo, Mahari Okbasillassie. "Land tenure in the highlands of Eritrea, economic theory and empirical evidence." [Ås, Norway] : Norges landbrukshøgskole, 2003. http://www.nlh.no/ios/Publikasjoner/avhandling/a2003-3.pdf.

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Thesis--Norges Landbrukshøgskole, Institutt for økonomi og samfunnsfag, 2003.
Title from title screen (viewed June 1, 2004). Includes bibliographical references (p. 200-204). Also issued in print format.

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Ebanezar, John Angelin [Verfasser]. "Negative Ion formation in Ion-Molecule and Ion-Surface collisions / Angelin Ebanezar John." Greifswald : Universitätsbibliothek Greifswald, 2014. http://d-nb.info/1061064654/34.

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Shen, Kuan-Hsuan. "Modeling ion conduction through salt-doped polymers: Morphology, ion solvation, and ion correlations." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595422569403378.

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Cederlund, Jacob, and Carmen Dahlin. "Analysis of the ion Composition in the Io Plasma Torus From Observations by the New Horizons Mission." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-239381.

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The object of this project is to analyse data from the plasma torus around Jupiter. The material in the plasma supplied by Jupiter’s moon Io is composed mostly of the elements oxygen and sulphur at different ionisation states and the torus has a changing environment. The goal is to analyse the composition of the torus and calculate the ratios between the two elements as well as the ions of each element and compare it to previously done research.The images that are analysed were taken by the spectrograph Alice on board the space probe New Horizons, during its flyby of Jupiter in 2007. The images were taken in the range of 520 - 1870 Å. The atomic database CHIANTI is used to simulate a spectrum and compare it with the data from the New Horizons mission and calculate the ratios.The analysis of the spectrum shows that the ratio of oxygen to sulphur in the Io plasma torus was lower in 2007 than previously seen, as well as a higher O+ to O++ ratio than has been found in previous studies. This may be the result of the volcanic eruption of Tvashtar the same day as the data was gathered.

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Bissonnette, Martine C. "Ion/radical and ion/molecule complexes and ion structure assignments in the gas phase." Thesis, University of Ottawa (Canada), 1991. http://hdl.handle.net/10393/7731.

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The fragmentation mechanism of ionized neopentanol, (CH$\sb3$)$\sb3$CCH$\sb2$OH$\sp{+-}$, has been studied in great detail along with other C$\sb5$H$\sb $H$\sp{+-}$ isomers. The use of $\sp $C and D labelling was found an essential tool to establish the relation between the other species involved in the dissociation of neopentanol. The involvement of (CH$\sb3$)$\sb2$C$\sp{\cdot}$CH$\sb2\sp+$(O)HCH$\sb3$, (CH$\sb3$)$\sb3$C$\sp+$(O)HCH$\sb2$ and (CH$\sb3$)$\sb2$($\sp\cdot$CH$\sb2$)CCH$\sb2\sp+$OH$\sb2$ was essential to explain the H/D label exchange occurring upon fragmentation of neopentyl alcohol. An ion-dipole complex between methanol and ionized methyl propene is proposed as the final intermediate which leads directly to the products, methanol and ionized methyl propene. The results of the investigation of C$\sb7$H$\sb5\sp+$ ions from various precursor molecules are also described. The following compounds, which all produce C$\sb7$H$\sb5\sp+$ ions, were studied: benzyl acetate, benzyl formate, benzyl alcohol, 2-bromocyclopropabenzene, 1,6-heptadiyne and 1,5-decadiyne. According to the metastable ion (MI) mass spectra and the He collision induced dissociation (CID) of m/z 89 ions, it is suggested that four structures exist. (Abstract shortened by UMI.)

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Li, Libing. "Strategies for secondary ion yield enhancements in focused ion beam secondary ion mass spectrometry." Thesis, Imperial College London, 2010. http://hdl.handle.net/10044/1/11806.

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Soyk, Matthew W. "Instrumentation development for coupling ion/ion reactions and ion mobility in biological mass spectrometry." [Ames, Iowa : Iowa State University], 2008.

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Bozkurt, Bilge. "Dynamic Ion Behavior In Plasma Source Ion Implantation." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607025/index.pdf.

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The aim of this work is to analytically treat the dynamic ion behavior during the evolution of the ion matrix sheath, considering the industrial application plasma source ion implantation for both planar and cylindrical targets, and then to de-velop a code that simulates this dynamic ion behavior numerically. If the sepa-ration between the electrodes in a discharge tube is small, upon the application of a large potential between the electrodes, an ion matrix sheath is formed, which fills the whole inter-electrode space. After a short time, the ion matrix sheath starts moving towards the cathode and disappears there. Two regions are formed as the matrix sheath evolves. The potential profiles of these two regions are derived and the ion flux on the cathode is estimated. Then, by us-ing the finite-differences method, the problem is simulated numerically. It has been seen that the results of both analytical calculations and numerical simula-tions are in a good agreement.

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Allan, Scott Young. "Ion Energy Measurements in Plasma Immersion Ion Implantation." The School of Physics. The Faculty of Science, 2009. http://hdl.handle.net/2123/5338.

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Doctor of Philosophy (PhD)
This thesis investigates ion energy distributions (IEDs) during plasma immersion ion implantation (PIII). PIII is a surface modification technique where an object is placed in a plasma and pulse biased with large negative voltages. The energy distribution of implanted ions is important in determining the extent of surface modifications. IED measurements were made during PIII using a pulse biased retarding field energy analyser (RFEA) in a capacitive RF plasma. Experimental results were compared with those obtained from a two dimensional numerical simulation to help explain the origins of features in the IEDs. Time resolved IED measurements were made during PIII of metal and insulator materials and investigated the effects of the use of a metal mesh over the surface and the effects of insulator surface charging. When the pulse was applied to the RFEA, the ion flux rapidly increased above the pulse-off value and then slowly decreased during the pulse. The ion density during the pulse decreased below values measured when no pulse was applied to the RFEA. This indicates that the depletion of ions by the pulsed RFEA is greater than the generation of ions in the plasma. IEDs measured during pulse biasing showed a peak close to the maximum sheath potential energy and a spread of ions with energies between zero and the maximum ion energy. Simulations showed that the peak is produced by ions from the sheath edge directly above the RFEA inlet and that the spread of ions is produced by ions which collide in the sheath and/or arrive at the RFEA with trajectories not perpendicular to the RFEA front surface. The RFEA discriminates ions based only on the component of their velocity perpendicular to the RFEA front surface. To minimise the effects of surface charging during PIII of an insulator, a metal mesh can be placed over the insulator and pulse biased together with the object. Measurements were made with metal mesh cylinders fixed to the metal RFEA front surface. The use of a mesh gave a larger ion flux compared to the use of no mesh. The larger ion flux is attributed to the larger plasma-sheath surface area around the mesh. The measured IEDs showed a low, medium and high energy peak. Simulation results show that the high energy peak is produced by ions from the sheath above the mesh top. The low energy peak is produced by ions trapped by the space charge potential hump which forms inside the mesh. The medium energy peak is produced by ions from the sheath above the mesh corners. Simulations showed that the IED is dependent on measurement position under the mesh. To investigate the effects of insulator surface charging during PIII, IED measurements were made through an orifice cut into a Mylar insulator on the RFEA front surface. With no mesh, during the pulse, an increasing number of lower energy ions were measured. Simulation results show that this is due to the increase in the curvature of the sheath over the orifice region as the insulator potential increases due to surface charging. The surface charging observed at the insulator would reduce the average energy of ions implanted into the insulator during the pulse. Compared to the case with no mesh, the use of a mesh increases the total ion flux and the ion flux during the early stages of the pulse but does not eliminate surface charging. During the pulse, compared to the no mesh case, a larger number of lower energy ions are measured. Simulation results show that this is caused by the potential in the mesh region which affects the trajectories of ions from the sheaths above the mesh top and corners and results in more ions being measured with trajectories less than ninety degrees to the RFEA front surface.

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Vörös, Ondrej. "Návrh IoT zařízení komunikujícího pomocí standardu NB-IoT." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-400550.

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This diploma thesis deals with the design of low-power IoT device communicating by using the NB-IoT standard. The theoretical part of the thesis is dedicated to the explanation of the principles and capabilities of communication in IoT networks Sigfox, LoRa and NB-IoT, and also its physical layer, network architecture, techonology principles and frequency bands used. The application part of the thesis is dedicated to design of the NB-IoT device from the system design through the selection of main components to the detailed physical design of the device. Two prototypes of the device with two different radio modules used are fabricated on which is performed measurement of the power profile of the device in various operation modes.

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Mohammadnia, Hamzeh. "IoT-NETZ: Spoong Attack Mitigation in IoT Network." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-260250.

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The phenomenal growth of the Internet of Things (IoT) and popularity of the mobile stations have rapidly increased the demand of WLAN network (known as IEEE 802.11 and WiFi). WLAN is a low-cost alternative of the cellular network and being an unlicensed spectrum to build the master plan of embedding the Internet in everything -&-anywhere. At the same time, monitoring the number of IoT and WiFi-enabled devices across residential and enterprises is not trivial. Therefore, future WiFi network architecture requires an agile management paradigm to provide internal support and security for WiFi networks.The operation of IoT and mobile device applications relies on scalability and high-performance computing of clouds. Cloud computing has completely centralized the current data center networking architecture and it provides computation-intensive, high-speed network, and realtime responses to the requests of IoT. The IoT-to-cloud communication is the essence of network security concerns and it is in grievous need of constant security improvement along the inter-networking. Based on the number of researches and analysis on generated traffic by IoT, it has been observed there are the significant number of massive spoofing-oriented attacks targeting cloud services are launched from compromised IoT.On the basis of reviewing prior researches on mostly-conducted network attacks by IoT, there is a challenging and common characteristic which has been frequently utilized in the numerous massive Internet attacks, known as spoofing. This work will survey the existing proposed solutions which have been deployed to protect both traditional and softwarized network paradigms. Then, it proposes the approach of this work that enables IoT-hosting networks protected by employing Software-defined Wireless Networking (SDWN) within the proposed model to mitigate spoofing -oriented network attacks. In addition, the proposed solution provides the environmental sustainability feature by saving power consumption in networking devices during network operation. The practical improvement in the proposed model is measured and evaluated within the emulated environment of Mininet-WiFi.
Den fenomenala tillväxten av IoT och populariteten hos mobilstationerna har snabbt ökat efterfrågan på WLAN-nätverk (känd som IEEE 802.11 och WiFi). WLAN är ett billigt alternativ för mobilnätet och är ett olicensierat spektrum för att bygga huvudplanen för att bädda in Internet i allt-och-var som helst. Samtidigt är det inte trivialt att övervaka antalet IoT och WiFi-aktiverade enheter över bostäder och företag. Därför kräver framtida WiFi nätverksarkitektur ett smidigt hantering paradigm för att tillhandahålla internt stöd och säkerhet för WiFi-nätverk.Användningen av IoT och mobilanvändningsapplikationer är beroende av skalbarhet och högpresterande beräkningar av moln. Cloud computing har helt centraliserat den nuvarande datacenters nätverksarkitektur och det ger beräkningsintensiva, höghastighetsnätverk och realtidssvar påbegäran från IoT. IoT-till-moln kommunikationen är kärnan i nätverkssäkerhetshänsyn och de har ett allvarligt behov av ständig förbättring och säkerhetshärdning inom deras internätverk. Baserat på antalet undersökningar och analyser av genererad trafik av IoT har det observerats. Det finns det betydande antalet massiva spoofing-orienterade attacker som riktar sig mot molntjänster, lanseras från komprometterad IoT.På grundval av att granska tidigare undersökningar om IoTs mest genomförda nätverksattacker finns det en utmanande och gemensam egenskap som ofta utnyttjats i de många massiva internetattackerna. Detta arbete kommer att undersöka de befintliga lösningarna som har implementerats för att skydda både traditionella och mjukvariga nätverksparadigmer. Därefter föreslår det tillvägagångssättet för detta arbete som möjliggör IoT-värdnät skyddade genom att använda SDWN inom den föreslagna modellen för att mildra poofing-orienterade nätverksattacker. Dessutom erbjuder den föreslagna lösningen miljöhållbarhet genom att spara strömförbrukning i nätverksenheter under nätverksdrift. Den praktiska förbättringen av den föreslagna modellen mäts och utvärderas inom den omgivande miljön av Mininet-WiFi.

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Король, Н. В. "Технологія IoT." Thesis, Національний авіаційний університет, 2020. https://er.nau.edu.ua/handle/NAU/51032.

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IoT (Internet of things) – це сукупність усіх фізичних об’єктів, об’єднаних в одну мережу та в яких вбудовані технології для комунікації один з одним або з зовнішнім світом. IoT розглядається, як мережа, яка спроможна покращити та полегшити більшу частину видів нашої діяльності. Поширення даної технології може створити нову еволюцію всіх пристроїв, які можуть мати доступ до мережі Інтернет. Пристрої, які базуються на аналітиці даних, вони спроможні отримувати , аналізувати та обмінюватись інформацією.

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McVeigh, Ryan. "Biologically enhanced ion exchange of ammonium ion using clinoptilolite." Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247390.

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Sterling, Robin C. "Ytterbium ion trapping and microfabrication of ion trap arrays." Thesis, University of Sussex, 2012. http://sro.sussex.ac.uk/id/eprint/39684/.

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Over the past 15 years ion traps have demonstrated all the building blocks required of a quantum computer. Despite this success, trapping ions remains a challenging task, with the requirement for extensive laser systems and vacuum systems to perform operations on only a handful of qubits. To scale these proof of principle experiments into something that can outperform a classical computer requires an advancement in the trap technologies that will allow multiple trapping zones, junctions and utilize scalable fabrication technologies. I will discuss the construction of an ion trapping experiment, focussing on my work towards the laser stabilization and ion trap design but also covering the experimental setup as a whole. The vacuum system that I designed allows the mounting and testing of a variety of ion trap chips, with versatile optical access and a fast turn around time. I will also present the design and fabrication of a microfabricated Y junction and a 2- dimensional ion trap lattice. I achieve a suppression of barrier height and small variation of secular frequency through the Y junction, aiding to the junctions applicability to adiabatic shuttling operations. I also report the design and fabrication of a 2-D ion trap lattice. Such structures have been proposed as a means to implement quantum simulators and to my knowledge is the first microfabricated lattice trap. Electrical testing of the trap structures was undertaken to investigate the breakdown voltage of microfabricated structures with both static and radio frequency voltages. The results from these tests negate the concern over reduced rf voltage breakdown and in fact demonstrates breakdown voltages significantly above that typically required for ion trapping. This may allow ion traps to be designed to operate with higher voltages and greater ion-electrode separations, reducing anomalous heating. Lastly I present my work towards the implementation of magnetic fields gradients and microwaves on chip. This may allow coupling of the ions internal state to its motion using microwaves, thus reducing the requirements for the use of laser systems.

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Rosenberg, Ron S. M. Massachusetts Institute of Technology. "Screen-printed ion selective electrodes for soil ion detection." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/110884.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 187-192).
Rural Indian farmers lack an available, affordable, usable, and actionable means to diagnose soil health, which is a prerequisite for judicious application of fertilizer. Although government labs and mobile kits are available, these fail to meet the aforementioned qualities; as a result fewer than 5% of rural Indian farmers have ever performed a soil test. This thesis details the design and characterization of a point-of- use soil testing device, comprising a set of disposable ion-selective electrode (ISE) strips and a handheld electrochemical reader, which together transduce soil analyte concentrations into a numeric input for a mobile-phone based fertilizer recommendation engine. As a proof-of-concept, potassium (K+) selective electrodes are studied, because K+ is essential to plant growth and reproduction. The strips employ a simple two electrode system, wherein carbon nanotube and silver chloride inks are the electrode contacts, plasticizer-free butyl acrylate ion selective membranes are located on the working electrodes, and sodium-chloride doped polyvinyl butyral membranes provide stable reference potentials. The electrodes were fabricated by a combined screen printing and drop casting process, and the protocol, extraction solution, and reference potential stability were tuned to maximize ISE performance and repeatability. Using a mathematical model and supporting experiments, we verified that hydrogen selectivity determines the detection limit, and furthermore, that scientists can tune the ionophore-ionic site ratio to minimize this effect. Using the final electrode fabrication process, a set of 20 full ISE devices in the presence of 0.02M SrCl2 extraction solution were shown to have sub-uM detection limits and near-Nernstian average sensitivity (61 mV/decade). When compared to ICP data for a set of 30 soil samples using the final reader, the sensors demonstrated a 0.898 correlation factor. Workshops in India were conducted to determine user needs and corresponding product attributes, as well as a "usability index" for the system assessed across farmer demographics. The favorable system performance proves that solid-state ISEs are a promising technology for soil diagnostics in resource-constrained environments.
by Ron Rosenberg.
S.M.

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Perez, Martinez Carla S. (Carla Sofia). "Engineering ionic liquid ion sources for ion beam applications." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/105605.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 177-186).
Ionic liquid ion sources (ILIS) are devices capable of producing positive and negative molecular ion beams through field evaporation from room-temperature molten salts. If sufficiently high hydraulic impedance from the liquid-supporting emitter is provided such that the ratio of flow rate Q to liquid's electrical conductivity K is sufficiently small, a pure ionic regime (PIR) can be achieved, in contrast with traditional electrosprays that produce charged droplets, or mixtures of droplets and ions. The PIR provides high current density from a point source, making ionic liquid ion beams suitable for use in focused ion beam (FIB) applications. The use of ionic liquids in focused ion beams could allow the production of sub-100 nm beams of up to kiloDalton organic ions as well as reactive species, with the possibility of engineering ionic liquid properties for a specific application. In addition, using micro-fabricated and nano-structured emitter arrays operating in the PIR can give access to efficient and compact positive or negative ion sources, for applications from spacecraft thrusters to deep reactive ion etchers (DRIE). There is a need for novel tip geometries and materials that favor the stable formation of a single emission site on the liquid supporting structure, while providing a continuous liquid supply compatible with the PIR. In this thesis, porous carbon based on resorcinol-formaldehyde xerogels is introduced as an emitter substrate. The target pore sizes and emitter geometries to attain the PIR are obtained through analytical estimates. The carbon xerogel can be shaped to the required micron-sized geometry through mechanical polishing. Time-of-flight mass (TOF) spectrometry is used to verify that charged particle beams produced from the mechanically polished carbon xerogel source, infused with the ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI-BF₄), contain solvated ions exclusively. In the case of the liquid 1-ethyl-3-methylimidazolium bis(trifluorometrylsulfonyl)imide (EMI-Im), mixed ion-drop operation is obtained. Laser micro-machining has been validated as a manufacturing technique to shape carbon xerogel into emitters. This technique should allow the production of emitter arrays for DRIE or propulsion applications, and allow the reproducible fabrication of emitters for FIB. Stable emission has been obtained from a laser micromachined tip infused with the ionic liquid EMI-BF₄ . The results of TOF and retarding potential analysis (RPA) experiments indicate that the emission consists mostly of monomers and dimers, and that a small fraction (< 5%) of the beam might be composed of cluster ions with greater degrees of solvation. To conclude, the thesis reports on the etching properties of the beams obtained from ILIS, both in the case of traditional externally wetted tungsten sources and with the novel carbon xerogel emitter technology. The W ILIS etches silicon with sputtering rates between 6 and 35 atoms of silicon removed per incident ion at 15 keV irradiation energies, whereas the carbon xerogel ILIS has been used to etch gold, silicon and gallium nitride with sputtering rates in the order of 10 for irradiation energies between 2 and 7 keV.
by Carla S. Perez Martinez.
Ph. D.

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Kuzema, O. S., and P. O. Kuzema. "Ion Probe with Primary ion Beam Prism Mass Separator." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35627.

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It has been considered the ion-optical properties and characteristics of ion microprobe analyzer in which the primary ion beam mass separation is realized by the magnetic prism, and the beam spherical capacitor is used in the secondary ion analyzing system as energy analyzer which form parallel ion beam at the mass analyzer inlet. It has allowed to improve the instrument parameters and to scale down its overall dimension. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35627

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Shi, Yu. "Single-ion Hydration and Ion Association in Aqueous Solutions." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439310243.

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Marto, Jarrod A. "External Ion Injection and Applications of Ion Axialization in Fourier Transform Ion Cyclotron Resonance Mass Spectrometry /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487868114113087.

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Torres, Theresa Ann. "Development of Fourier transform ion cyclotron resonance mass spectrometry for the study of ion-ion reactions /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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Li, Ailin. "Miniaturization of Linear Ion Traps and Ion Motion Study in a Toroidal Ion Trap Mass Analyzer." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6503.

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I describe the miniaturization of a linear-type ion trap mass spectrometer for possible applications in portable chemical analysis, and demonstrate the advantages of using lithographically patterned electrode plates in realizing an ion trap with dimension r0 less than 1 mm. The focus of the work was to demonstrate the viability and feasibility of the patterned electrode approach to trap miniaturization, and also to discover potential obstacles to its use. Planar ceramic substrates were patterned with metal electrodes using photolithography. Plates that were originally used in a linear trap with a half-spacing (r0) of 2.19 mm were positioned much closer together such that r0 = 0.95 mm. A capacitive voltage divider provided different radiofrequency (RF) amplitudes to each electrode, and the capacitor values were adjusted to provide the correct electric field at this closer spacing. Electron ionization mass spectra of toluene and dichloromethane demonstrate instrument performance with better than unit mass resolution. Compared with the larger plate spacing, the signal intensity is reduced, corresponding to the reduced trapping capacity of the smaller device, but the mass resolution of the larger device is retained. A further miniaturized linear ion trap with a half-spacing of 362 µm was designed and tested. A series of obstacles and troubleshooting on ion source, analytical method, and electronics were present. These experiments show promise for further miniaturization using patterned ceramic plates and provide a guide for the ion trap miniaturization. The feasibility of a wire linear ion trap was also demonstrated. Unit mass resolution was obtained, indicating a promise for further optimization and miniaturization of the wire linear ion trap. In addition to the practical experiments on the miniaturized linear ion traps, I theoretically studied ion motion in the toroidal ion trap using SIMION simulations, which show classical chaotic behavior of single ions. The chaotic motion is a result of the non-linear components of the electric fields as established by the trap electrodes, and not by Coulombic interaction from other ions. The chaotic behavior was observed specifically in the ejection direction of ions located in non-linear resonance bands within and adjacent to the region of stable trapping. The non-linear bands crossing through the stability regions correspond to hexapole resonance conditions, while the chaotic ejection observed immediately adjacent to the stable trapping region corresponds to a "fuzzy" ejection boundary. Fractal-like patterns were obtained in a series of zoomed-in regions of the stability diagram.

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Fowles, Jonathon Richard. "Characterization of the skeletal muscle sodium ion-potassium ion-ATPase, and the acute effects of exercise on sodium ion-potassium ion-ATPase activity." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ65239.pdf.

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Ali, Safdar. "Electron - Ion Recombination Data for Plasma Applications : Results from Electron Beam Ion Trap and Ion Storage Ring." Doctoral thesis, Stockholms universitet, Fysikum, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-75311.

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This thesis contains results of electron-ion recombination processes in atomic ions relevant for plasma applications. The measurements were performed at the Stockholm Refrigerated Electron Beam Ion Trap (R-EBIT) and at the CRYRING heavy-ion storage ring. Dielectronic recombination (DR) cross sections, resonant strengths, rate coefficients and energy peak positions in H-like and He-like S are obtained for the first time from the EBIT measurements. Furthermore, the experimentally obtained DR resonant strengths are used to check the behaviour of a scaling formula for low Z, H-and He-like iso-electronic sequences and to update the fitting parameters. KLL DR peak positions for initially He- to B-like Ar ions are obtained experimentally from the EBIT measurements. Both the results from highly charged sulfur and argon are compared with the calculations performed with a distorted wave approximation. Absolute recombination rate coefficients of B-like C, B-like Ne and Be-like F ions are obtained for the first time with high energy resolution from storage ring measurements. The experimental results are compared with the intermediate coupling AUTOSTRUCTURE calculations. Plasma rate coefficients of each of these ions are obtained by convoluting the energy dependent recombination spectra with a Maxwell-Boltzmann energy distribution in the temperature range of 103-106 K. The resulting plasma rate coefficients are presented and compared with the calculated data available in literature.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Accepted. Paper 5: Accepted. Paper 6: Manuscript. Paper 7: Manuscript.

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Zhao, Qin. "Development of ion mobility mass spectrometry coupled with ion/ion reactions instrumentation and applications for protein analysis /." [Ames, Iowa : Iowa State University], 2009.

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Hornsey, Richard Ian. "Factors affecting ion energy distributions in liquid metal ion sources." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236154.

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Papadopoulos, S. "Atomic and cluster ion emission from liquid metal ion sources." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375310.

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Scrivens, R. M. "Extraction of an ion beam from a laser ion source." Thesis, Swansea University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638785.

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The CERN Laser Ion Source (LIS) aims to provide a short pulse (5 μs), high current ( 10mA) and high charge state heavy ion beam (Pb²⁵⁺) for acceleration by a LINAC and injection into the Proton Synchrotron Booster (PSB). The laser beam time profile was measured using detectors with time response of the order of 1 ns. Cross correlating of the laser pulse form and the ion beam current one fails to find any significant relation. The laser spatial profile was measured in the focal plane by a Spiricon pyroelectric camera in conjunction with a long focal length lens. In the Master Oscillator and Power Amplifier laser configuration, the beam was found to be astigmatic and exhibit a large pointing instability. The free-running laser produced a beam in good agreement with the simulation of beam propagation along the 30 m path extension and was also astigmatic. As for the time profile, no firm correlation of the laser spatial profile fluctuation and the ion beam instability could be found. Within the framework of this thesis, a critical study has been performed on whether shot-to-shot instabilities are being caused by fluctuation in the laser beam parameters (time profile, spatial distribution and energy) as well as the extraction of the ions from the expanded laser plasma to form an ion beam. In addition, a technique for the calculation of absolute ion numbers was derived. The extraction of the ions from the laser ion source plasma was experimentally studied using Faraday cup collectors, and a compact single shot emittance measurement system. The extraction of the ions was found to be correctly modelled by the Child-Langmuir equations for charge extraction, with some modification necessary to account for the initial significant ion velocity (10⁵ ms^-1) found after plasma expansion. The equivalent proton perveance applicable to the extraction geometry used, was found by systemic measurements of the ion transmission to a Faraday cup as a function of the applied source voltage. Absolute ion numbers were calculated from measurements using an electrostatic ion analyser and a Faraday cup ion collector. From these measurements it was possible to deduce the transmission losses through the Low Energy Beam transport line between the LIS and an RFQ; they were found to be as high as 80%. In summary, the measurements detailed here allow the prediction of the source parameters required for extraction of a higher current, higher charge state beam required for a final LIS implementation capable of supplying the ion beam for the Large Hadron Collider (LHC). In addition, simulations of the beam extraction using a time dependent macro-particle and static ray-tracing software package are described which provide a reasonably good modelling of the beam extraction.

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Scott, Graham Bruce Ian. "Experimental studies of astrochemical ion-atom and ion-molecule reactions." Thesis, University of Canterbury. Chemistry, 1997. http://hdl.handle.net/10092/7813.

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Data is presented for a number of ion-molecule and ion-atom reactions of likely relevance to the chemistry of interstellar clouds and planetary atmospheres. The measurements were made using a Selected Ion Flow Tube, (SIFT), operating at ambient temperatures, (300 ± 5 K), and at pressures between 0.30 - 0.35 Torr. The reactivity of two C₃H₃0+ isomers, namely protonated propynal, (HC=C-CHOH⁺), and the association product of C₂H₃⁺ with CO, (C₂H₃.CO), were characterised in laboratory experiments. These measurements bracket the proton affinity of propynal between 759 and 736 kJ mol⁻¹. The proton affinity of propadienone is similarly constrained between 896 and 868 kJ mol⁻¹. In a complementary investigation, the C₃H₃0⁺ potential surface was mapped using ab-initio calculations at the G2 level of theory. This combined experimental/theoretical study demonstrates that the condensation product between C₂H₃⁺ and CO is C₂-protonated propadienone, (H₂C=CH-C=O). Consequently, this finding indicates that propynal is not synthesised in the interstellar medium via the reaction of C2H3 + with carbon monoxide. The reactions between twenty-eight cations and molecular and atomic hydrogen were examined in a series of laboratory experiments. Most hydrocarbon cations react with H atoms by termolecular association or, alternatively, H atom transfer routes. In contrast, only unsaturated hydrocarbon cations tend to react with H₂ via H atom abstraction processes. There are fewer clear trends evident in the reactions between non-hydrocarbon ions and H atoms. If exothermic, H atom abstraction is almost always observed during reactions between non-hydrocarbon cations and H₂. Molecular and atomic hydrogen are both extremely plentiful in dense and diffuse interstellar clouds and these processes are therefore particularly relevant to the chemistry occurring within these objects. Results are presented for the reaction of approximately thirty cations with molecular and atomic nitrogen. Most ions are unreactive with N₂, however atomic nitrogen is a more reactive neutral species. Small hydrocarbon cations react with N atoms by forming C-N bonds and eliminating H or H₂, while larger CmHn⁺ species react with this neutral by forming HCN and a fragment hydrocarbon ion. In general there are no obvious patterns to the reactivity of non-hydrocarbon cations with atomic nitrogen. These processes are pertinent both to interstellar chemistry and the aeronomy of nitrogenous planetary atmospheres. The crucial reaction between H3 + and N has been measured for the first time in the laboratory and found to be rapid, (k= 4.5 x 10⁻¹⁰cm³). This result offers an alternative, (and possibly more facile), synthetic route to ammonia in interstellar clouds. Data is reported for the reaction of nineteen cations with O atoms, O₂ and NO. Small and medium sized hydrocarbon cations react with O atoms forming CmHnO⁺ ions and an H or H₂ fragment, whilst larger CmHn⁺ ions often react by C atom transfer forming CO and a smaller hydrocarbon ion. Most non-hydrocarbon cations examined were unreactive with atomic oxygen. Molecular oxygen is relatively unreactive with most ionic species, however many ions react with NO by charge transfer and/or termolecular association pathways. Nitric oxide, O₂ and O atoms are all present to varying degrees in interstellar clouds, hence the measurements presented here are applicable to the chemistry of these objects. A number of preliminary experiments between ions and atomic carbon are detailed. The techniques for generating C atoms are described. The research described in this thesis is pertinent to the many environments in which plasmas occur.

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Lambrecht, Alexander [Verfasser], and Tobias [Akademischer Betreuer] Schätz. "Optical ion trapping with regard to ultracold atom-ion experiments." Freiburg : Universität, 2017. http://d-nb.info/1136567089/34.

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Murrell, Jason. "Some studies in ion/molecule reactions on ion trapping instruments." Thesis, University of Kent, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319223.

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Bahaffi, Saleh Omar Saeed. "An investigation of ion-exchangers for ion chromatography of anions." Thesis, University of Kent, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328170.

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Franklin, A. M. "Computational applications and ion behaviour in ion trap mass spectrometer." Thesis, University of Kent, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294313.

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Pearson, C. H. G. "New ion exchange resins for ion chromatography applied to anions." Thesis, University of Kent, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372771.

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Orrman-Rossiter, Kevin G. "Ion scattering analysis of low energy ion bombarded GaAS(001)." Thesis, University of Salford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327940.

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Holden, Nicola Kathleen. "Atmospheric ion measurements using novel high resolution ion mobility spectrometers." Thesis, University of the West of England, Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288184.

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Gallen, Niall Anthony. "Ion implantation waveguide formation in transition metal ion doped insulators." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310665.

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