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Dissertations / Theses on the topic 'SPRAD'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Orreill, Anthony John, and n/a. "Selected effects of a school performance review and development process (SPRAD) on parent participation in a school and parent/teacher relationships : a single site case study." University of Canberra. Professional & Community Education, 1996. http://erl.canberra.edu.au./public/adt-AUC20060823.160212.

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School Performance Review and Development (SPRAD) was a major innovation in school evaluation in the Australian Capital Territory. One of its aims was to encourage teachers and parents to work together in evaluating and developing policy across all areas of school life: Administration and Management, Finances, Curriculum and Assessment, Staff and Student Welfare and overall School Climate. SPRAD is different from other forms of school review in that it is system-initiated but kept under the control of the participants. The ACT Department of Education and Training supplies the resourcing and consultative assistance. One of the hopes for SPRAD was that, in bringing teachers and parents closer together, it would create a greater understanding of where each group stood in relation to the other and strengthen parent/teacher relationships. The focus areas for this study were parent participation in classroom and related activities, the various channels of information employed within the school such as school newsletters, reports and interviews, specific notices and letters relaying matters peculiar to class groups and school sectors, parent/teacher information-sharing sessions, parent/teacher involvement in board and P & C activities, and other forms of formal and informal contact. The study highlights the differences and similarities between teachers and parents in relation to "professionalism" and "partnership", and areas of conflict highlighted by Beacham & Hoadley (1979) who discuss the Fortress Model of Schooling, and Darland (lanni et al: 1975) who writes of the "anyone can teach attitude" displayed by many members of the public, i.e. the attitude that because all people have had some experience of schooling, then their opinions on education carry as much weight as those of the professionals; the feeling that what was good for them is good for their children, because they have "been there, done that" and teachers do not really know very much more than they (the public) do. SPRAD was seen to be a helpful factor in developing some aspects of parent/teacher relationships. Satisfaction with parent participation in classroom activities had increased overall despite some drops in actual parent presence at the activities because of the movement of children into the Senior areas of the school. Another example was the lessening of the degree of dissatisfaction with teachers' professional development programmes, especially pupil-free school development days.

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2

Gove, Benedict. "The impact of pesticide spray drift and fertiliser over-spread on the ground flora of ancient woodland." Thesis, Imperial College London, 2004. http://hdl.handle.net/10044/1/7226.

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3

Chang, Jy-Cheng. "Diesel spray characteristics and spray/wall heat transfer." Thesis, Imperial College London, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295616.

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4

Mabey, Katie E. "Coanda-Assisted Spray Manipulation Implementation to Plasma Spray." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/997.

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Coanda-assisted Spray Manipulation (CSM) is a means of modifying the direction of a jet. Previous isothermal static vectoring research is expanded to plasma spray. Two- dimensional Particle Image Velocimetry (PIV) was used to determine the vectoring results for small angles between 5-10°. Suitable parameters were determined for use on a plasma spray gun for small angle vectoring. Three-dimensional PIV was used to determine the elect of high speed rotation on a vectored jet. A 2-piece CSM collar was retrotted to a Praxair SG-100 plasma spray gun that replaced the standard faceplate. Two separate collars were tested: one designed for small vector angles and one for larger vector angles. The small-angle device could modify the trajectory of zirconia powder up to several degrees. Doing so could realign the plasma with the powder, resulting in increased powder temperature and velocity. The large-angle device could vector the plasma jet up to 45°; however the powder did not vector as much. Under large-angle vectoring, the powder velocity and temperature decreased steadily with vector angle. Both devices were tested using a supersonic conguration.

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5

Salinas, Angel G. "Spray generation." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1999. http://handle.dtic.mil/100.2/ADA370728.

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Thesis (M.S. in Mechanical Engineering) Naval Postgraduate School, September 1999.
"September 1999." Thesis advisor(s): T. Sarpkaya. Includes bibliographical references (p. 77). Also Available online.

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6

Eriksson, Johan, Joakim Oja, and Mattias Olsson. "OC-spray." Thesis, Umeå University, Basic training programme for Police Officers, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-27186.

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En man skulle en kväll gripas av polis för våld mot tjänsteman. Han kunde utan större problem beläggas med handfängsel, men när mannen skulle sättas i polisbilen blev han helt plötsligt vansinnig och började sparka mot polisbilen och mot en polis. Situationen blev ohållbar och mannen sprayades med pepparspray i ansiktet på ungefär 20 cm avstånd i cirka 5 sekunder. Resultatet var omedelbart, mannen bajsade ner sig och kunde lugnt transporteras till polisstationen. Det här var en situation tagen ur verkligheten och det är om detta som vårt arbete skall handla om. Vad oc-sprayens införande innebär för polisens arbete, hur självskyddet påverkas, hur taktiken vid ett ingripande påverkas samt hur våldsanvändningen vid ingripanden kan minskas i och med oc-spray, detta hänger mycket ihop med var sprayen placeras på våldstrappan. I samband med det har vi tittat på ett arbete från Skellefteå polisen där man tar upp bland annat taktik vid ett ingripande och hur placeringen då påverkar taktiken. Detta kan man även dra vidare till polisens arbetsmiljö, man måste ju utveckla ett regelverk som gör att poliserna ute känner sig säkra på vad som gäller och som samtidigt sörjer för en god arbetsmiljö både för polisen och för personerna som de ingriper mot. Även för den delen är det Skellefteå polisens arbete som ligger till grund för vårt resonemang. Vi tar även upp hur examinationen ser ut för att få bära pepparspray och för det har vi läst polishögskolans utbildningsmaterial för oc-spray. Vidare skall vi även titta på om oc-sprayen kommer att nå den civila marknaden så att kanske även ordningsvakter i framtiden kommer att vara utrustade med oc-spray.

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7

Al-Hakim, Kassem. "An investigation of spray-freezing and spray-freeze-dryings." Thesis, Loughborough University, 2004. https://dspace.lboro.ac.uk/2134/12935.

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Drying is an important process for a variety of industries such as pharmaceuticals, food, and chemicals, and produce products with low bulk density, good shelf stability, economical storage and transport, and in some cases unique structural qualities. Of the various drying methods available, freeze-drying is the most beneficial for heat sensitive products that susceptible to thermal degradation. Freezedrying also confers a porous structure on the material result from the voids left after subliming the ice crystals. Freeze-drying however is used mainly for high value products due to the high capital and operational costs. The cycle time of such a drier may take several hours. The spray-freeze-drying process has evolved in an attempt to shorten the freezedrying process time. The process atomises a liquid feed to increase the heat and mass transfer surface area. The spray is then frozen in a very cold gas or a cryogenic liquid to form solid particles, which are then freeze-dried. Some processes incorporate a - fluidised bed freeze-drier to reduce the drying time by forced convection heat and mass transfer. This project aim to develop the Spray Freeze- Drying process and examine the effect of the process on the drying entities and resulting product quality, followed by modelling of the spray freezing operation in an attempt to optimise the operation. This thesis is divided into two main areas of investigations; Spray freezing investigation as an influential on the resulting product size and structure. The experiments performed using Phase Doppler Anemometry technique to measure the particle size distributions and velocities in a specially constructed spray freezing chamber with incorporated windows. A spray freeze-drying chamber was constructed composed of three parts co-current spray freezing, gas - particle separation, and fluidisation freeze-drying unites. Successfully spray characterisation measurement was carried in both ambient and sub-ambient temperatures, producing data of the drop size distribution and velocities from refractive scattered laser PDA measurement. The technique produced valuable information about the spray size distribution and velocity, the application of this technique appear was a novel approach in the spray freezing process measurement. The result were used in the established spray freezing model derived from Pham (1984) freezing model incorporating with a recalescence stage from the Hindmarsh (2003) spray freezing model. The current model predicted the droplet freezing time, which is influenced by the droplet diameter, velocity and freezing gas temperature. The results also shows an agreement between the freezing time predicted and the PDA recognition of bursts rejected due to their possible phase change. The spray-freezing-drying chamber was operated in vacuum conditions to produce freeze-dried whey protein powder. The powder characteristic results shows an physical properties such as density, solubility and particle sizes in comparison to spray drying and cryo-spray freeze-drying. The morphology of the spray freeze-dried whey powder is substantially different to that produced by spray drying and displays a porous microstructure. The operation of the freeze-drying unites requires an further investigation for temperature, pressure, and flow control to maintain the freezedrying.

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8

Cutter, Paul. "Diesel spray characteristics, spray/wall interaction and heat transfer." Thesis, Imperial College London, 1996. http://hdl.handle.net/10044/1/7524.

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9

Vorster, Willem Johannes Jacobus. "Spray quench processing." Thesis, University of Oxford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531785.

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10

Threlfall-Holmes, Philip Nigel. "Spray dryer modelling." Thesis, Heriot-Watt University, 2009. http://hdl.handle.net/10399/2292.

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Both spraying and drying are critical to spray dryer performance. Models are developed which explain the very different performance of a spray dryer when large droplets of film forming materials are created using a Rayleigh resonance atomiser. The droplet diameter distribution from this "Acoustic Atomiser" is inadequately described by previously reported spray size distribution functions, but well described by the Stable distribution. The alpha parameter of this distribution was found to tend towards the Gaussian limit for low viscosity fluids and the Lorentz limit with increasing viscosity, consistent with behaviour as a simple and damped forced harmonic oscillator respectively, and hence with the physics of the atomisation process. Droplet drying kinetics dominate model predictions. A device using an ultramicrobalance to measure droplet drying kinetics with unprecedented accuracy and range has been designed. A scaling and residence time analysis model was able to account for experimental spray dryer observations. Sprayability even of complex fluids is predicted adequately by the Ohnesorge diagram, provided that extensional rather than shear viscosity is plotted. A new determination of the transient apparent extensional viscosity from arbitrary CaBER time-diameter curves has successfully been used for fluids too complex to analyse using previously published rheological models.

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11

Hrečka, Marek. "Obchodování futures spread." Master's thesis, Vysoká škola ekonomická v Praze, 2013. http://www.nusl.cz/ntk/nusl-198251.

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The purpose of the thesis is to identify factors that affect the profitability and risk of trading futures calendar spreads. The basic characteristics of futures and trading calendar spreads with seasonal time frames are described in the first part of the thesis. The selected factors such as the correlation of short-term and long-term seasonal patterns, the trading in the extreme, the trading single or multiple crops, the width of the seasonal window, the win probability, the length of backtested period and intermarket vs. intramarket spreads are analyzed from the perspective of profitability and risk in the second part. A summary of the results is contained in the conclusion.

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12

Salomão, Wellington Fioravante. "Microencapsulação de dimetil dissulfeto (DMDS) por spray drying e spray congealing." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/60/60137/tde-29102012-141155/.

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O dengue e o dengue hemorrágico são considerados como as arboviroses mais importantes do ponto de vista da saúde pública além de serem também as mais disseminadas. O greening ou huanglongbing (HLB), por sua vez, é uma doença de difícil controle e rápida disseminação que afeta seriamente a produção de citros no mundo todo. É considerada a pior doença de citros da atualidade pois não tem cura e leva ao declínio e morte das árvores em alguns anos. O DMDS é um composto sulfúrico volátil derivado de plantas e que tem despertado um crescente interesse devido a sua comprovada atividade repelente e inseticida além de ação nematicida e disinfectante do solo. Visando oferecer uma alternativa para o controle de ambas as doenças, este trabalho teve como objetivo desenvolver um método de microencapsulação por spray drying e spray congealing para o dimetil dissulfeto (DMDS), visando a redução da sua volatilidade através de uma liberação controlada para o ambiente. Dessa forma, tornar-se-ia viável sua utilização como repelente, larvicida e inseticida no combate ao vetor do dengue além da sua utilização como repelente no controle do greening nas lavouras de citrus. Tentou-se a microencapsulação através de spray congealing utilizando enxofre como microencapsulante mas não se obteve sucesso devido as características térmicas do enxofre. Foram obtidas micropartículas de DMDS microencapsulado em goma arábica através da técnica de spray drying. As micropartículas e o processo de secagem foram caracterizados com relação ao rendimento de secagem, rendimento de microencapsulação, morfologia, teor de água residual, atividade de água, densidades aparente e compactada e propriedades de fluxo. Confirmou-se a possibilidade de microencapsulação de DMDS por spray drying e eficiência da goma arábica na retenção do mesmo. As partículas obtidas apresentaram boas propriedades de atividade de água, teor de água residual e densidade mas propriedades de fluxo que requerem melhoria. Foi feito também um estudo simplificado da viabilidade técnico-econômica da implantação de uma unidade de produção de DMDS microencapsulado. Esse estudo foi baseado no processo de microencapsulação estudado. Foram analisados diversos parâmetros econômicos e através destas análises verificou-se que a produção de DMDS microencapsulado pelo método utilizado seria economicamente viável.
Dengue fever and dengue hemorrhagic fever are not only considered the most important arboviruses from public health standpoint but also the most disseminated ones. Greening or huanglongbing (HLB) is a citrus disease of difficult control and fast dissemination that affects citrus production all over the world. It is considered the worst citrus disease nowadays since it does not have a cure and it causes the decline and death of the trees in a few years. Dimethyl disulfide is a volatile sulphur compound derived from plants and that has aroused growing interest due to its proved repellence and insecticidal activity, soil disinfection and nematocidal properties. Therefore, this work aimed at developing a DMDS microencapsulation method via spray drying and spray congealing in order to decrease DMDS\' volatility through a controlled release to the environment and offer a control alternative to both diseases. This would make DMDS use as a repellent, larvicide and insecticide of dengue fever\'s vector and also its use in greening control as a repellent viable. We tried to microencapsulate the DMDS through spray congealing using sulfur as a microenpsulating agent but it was unsuccessful due to the thermal characteristics of sulfur. DMDS was microencapsulated in Arabic gum through spray drying. Drying yield, microencapsulation yield, morphology of the particles, residual water percentage, water activity, bulk and tapped density and flow properties were used to characterize the microparticles and the drying process. Feasibility of DMDS microencapsulation and Arabic gum efficiency in DMDS retention were confirmed. The microparticles presented good bulk and tapped density, residual water percentage and water activity properties though its flow properties requiring further improvement. A simplified technical-economical evaluation of a DMDS microencapsulation factory was also done. This evaluation was based on the studied microencapsulation process. Many economical parameters were analysed and those analyses showed that DMDS microparticles production using the studied method would be economically viable.

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13

Kolakaluri, Ravi. "Engine spray combustion modeling using unified spray model with dynamic mesh refinement." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1468103.

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14

Nilsson, Maria, and Elin Pettersson. "OC-spray : sekundär kontaminering." Thesis, Umeå University, Basic training programme for Police Officers, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-27568.

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Syftet med detta arbete är att undersöka hur vanligt förekommande sekundär kontaminering är vid användandet av OC – spray. Arbetet beskriver i vilka situationer sekundär kontaminering förekommer i det polisiära arbetet samt vad som kan göras för att minska förekomsten av det. Det inledande kapitlet beskriver OC – spray som är det senaste tillkomna hjälpmedlet för svensk polis, dess för – och nackdelar samt effekterna av den. För att syftet ska uppnås har en enkätundersökning genomförts samt har OC – rapporter studerats. Vidare behandlar arbetet även de riktlinjer som finns för användandet av OC – spray kopplat till de tre förhållningssätt som den svenska polisens nationella bastaktik utgörs av. Resultatet från enkätundersökningen och resultatet från OC – rapporterna visar att sekundär kontaminering är mycket vanligt förekommande och det framgår bl.a. att ett allt för kort sprayavstånd kan vara orsaken till detta. I det avslutande kapitlet diskuteras vilka möjligheter som finns för att minska risken för sekundär kontaminering samt vilka faktorer som spelar in för att uppnå ett önskvärt användande av OC - spray. Konkreta förslag ges beträffande sprayavstånd och stresshantering samtidigt som vikten av en väl fungerande kommunikation kollegor emellan belyses.

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15

Domann, Michael. "Characteristics of spray unsteadiness." Thesis, Imperial College London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268873.

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16

Bray, M. J. "Laser-assisted cold spray." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.596878.

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The aim of this research project was to develop a laser-assisted cold spray (LCS) system capable of applying well adhered, fully dense metal coatings to flat surfaces without melting the powder or substrate. It was necessary for the LCS process to retain the advantages of cold spray (CS) – namely solid state deposition and high build rate, but reduce operating costs by eliminating the gas heater and replacing helium with nitrogen as the process gas. Optimum deposition conditions were investigated and the deposits characterised in order to form comparisons with other spraying techniques and to identify the bonding process. Several objectives were set at the beginning of the project to define a possible route to developing a successful spraying technique. The project started with a literature review to gain an understanding of current spraying and cladding technologies, and coating properties that were sought after and achieved. A basic rig was designed and constructed to carry out proof of principle trials. The rig was then redesigned for better process capability, control, and data acquisition. A process optimisation study was carried out to identify key variables that needed to be controlled, and their effect on deposition. The process was found to be sensitive to deposition site temperature and particle velocity, and process parameters that affect these – such as laser power, gas pressure, traverse rate and powder feed rate. Materials analysis was carried out on samples produced using LCS under various conditions and compared to coatings produced using other spray techniques. By analysing single-particle impacts and coatings, and relating deposition conditions to existing theory, a deposition mechanism unique to LCS was proposed.

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17

Montgomery, Robert D. "Spread spectrum frequency management." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/26263.

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18

Savic, Sasha. "Liquid fuel spray characteristics." Thesis, University of Brighton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324470.

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19

Domann, Roland. "Characterisation of spray unsteadiness." Thesis, University of London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443683.

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20

Fiche, Marcelo Estrela. "Spread bancário no Brasil." reponame:Repositório Institucional da UnB, 2015. http://dx.doi.org/10.26512/2015.10.T.19981.

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Tese (doutorado)—Universidade de Brasília, Departamento de Economia, Brasília, 2015.
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Os componentes que respondem pelo elevado spread bancário no Brasil tem sido alvo de diversas análises nos últimos anos. As mudanças ocorridas no sistema financeiro brasileiro e o aumento da participação dos bancos públicos na economia provocaram elevação na concentração bancária no país. A maior parte das analises realizadas, buscando explicações para a formação do spread brasileiro, foram a partir de variações ex-ante, como sugere o nome, a partir das expectativas das instituições financeiras no momento da concessão do crédito, isto é, antes do resultado efetivo. Neste trabalho, os determinantes do spread bancário ex-post foram medidos pela margem financeira real dos principais bancos responsáveis pela intermediação financeira na economia brasileira, selecionando todas as instituições atuantes no Brasil com carteira comercial ativas no período analisado, 2000 a 2013 trimestralmente, chegando a um total de 149 instituições.
The components that are responsible for high banking spread in Brazil has been the subject of numerous analyses in recent years. The changes in the Brazilian financial system and increased participation of public banks in the economy caused increase in Bank concentration in the country. Most of the analyses carried out, seeking explanations for the formation of the Brazilian spread, were from ex-ante variations, as the name suggests, from the expectations of the financial institutions at the time of the granting of credit, that is, before the actual result. The determinants of banking spread were measured by the ex-post financial margin of leading banks responsible for financial intermediation in the Brazilian economy, selecting all the institutions operating in Brazil with active trading portfolio in the analysis period, 2000 to 2013 on a quarterly basis, reaching a total of 149 institutions.

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21

Tikkinen, N. (Nina). "Euribor basis swap spread." Master's thesis, University of Oulu, 2014. http://urn.fi/URN:NBN:fi:oulu-201406241775.

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The aim of the study is to investigate the factors affecting Euribor basis swap spreads. Variables are divided into three component; liquidity risk, credit risk, and macroeconomic and monetary policy. The Euribor basis swap was close to zero basis points, but during the early phases of the latest financial crises the spreads jumped. In empirical part of the study, the stationarity of the variables is tested. In the next step, Phillips-Ouliaris (P-O) co-integration test is tested to get 5 combinations that co-integrates with Euribor basis swap spread 3 month versus 12 month with 5 years to maturity. Thirdly, long-run equilibrium for the Models with Engle-Granger test is applied. Out of the five Models, picked in P-O, only three had long-run equilibrium. From the three long-run equilibrium Models the regression residuals are saved and estimated short-term equilibrium with Error Correction Model. At the end, Ordinary Least Square method with Newey-West corrections with the three co-integrated Models is tested. The variables for liquidity risk component are Open Market Operations, Aggregate Liquidity Factors, Deposit Facility, and Governing Council Meeting day -dummy. The variables for the credit risk component are Eurobond yield and Bank Credit Default Swap spread. The variables for the macroeconomic and monetary policy component are Euro Overnight-Index Average and exchange rate. The results show that the biggest determinants for the Euribor basis swap spread 3m vs 12m 5y are Open Market Operations, Meeting day, Eurobond yield 5y, Bank CDS, EONIA, and exchange rate of China.

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22

de, Rioja Victor Lopez, Joaquim Fort, and Neus Isern. "Spread of virus infections." Diffusion fundamentals 24 (2015) 11, S. 1, 2015. https://ul.qucosa.de/id/qucosa%3A14525.

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23

Khaleghi, Farideh. "Spread spectrum fiber LANs." Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7600.

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In this thesis, a hybrid scheme is proposed for the purpose of suppressing the effect of external modulation and/or laser nonlinearities in Subcarrier Multiplexing (SCM) fiber optic communications systems. Hybrid CDMA/FDMA combines two schemes in such a way that the resulting hybrid network is robust against interference and is much more spectrally efficient than a CDMA system. Several possible architectures for the hybrid CDMA/FDMA subcarrier fiber optic Local Area Network (LAN) are introduced. These networks utilize CDMA and SCM, an asynchronous multiple access scheme with no waiting time. Direct Sequence Spread Spectrum Multiple Access (DS/SSMA), the most common form of CDMA in which each user is assigned a particular code sequence which modulates the carrier along with digital data, is employed. It is shown that by using the code sequence sets for which the shift-and-add property holds, the Intermodulation Products (IMPs) and harmonics have a similar interference-like effect as the non-matching sequences. Owing to the fact that shift-and-add property holds for conventional spreading sequences, i.e., Gold, Kasami and maximal-length sequences, the suppression of nonlinearity distortion is evaluated. An average error probability performance evalution of the selected configuration for a transceiver pair is presented. In analysis of the system, we assume the interference term arising from other users is gaussian distributed. The results are compared to that obtained from exact evaluation of interference distribution using the Gauss Quadrature Rule integration (GQR) method. We compare the performance of this scheme for two different code sequence sets (N = 127 Gold and N = 255 Kasami codes) and determine that there is a significant advantage in deploying the N = 255 Kasami codes. We also present some preliminary experimental results on the proposed LAN implementation as well as the transmission performance. The results show great promise.

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de, Rioja Victor Lopez, Joaquim Fort, and Neus Isern. "Spread of virus infections." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-198089.

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25

Schmid, Katja. "Spray drying of protein precipitates and Evaluation of the Nano Spray Dryer B-90." Diss., lmu, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-131326.

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26

Tsai, Ming-Yi. "The Washington orchard spray drift study : understanding the broader mechanisms of pesticide spray drift /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/8471.

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27

Meng, Fanqi. "Trajectory and spray control planning on unknown 3D surfaces for industrial spray painting robot." [Ames, Iowa : Iowa State University], 2008.

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28

Raghuram, Avinash. "Experimental Analysis of Post-Impact Drop Spread Behavior and Prediction of Maximum Spread Factor." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1377868179.

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Pelissari, Julio Rafael. "Efeito da encapsulação de licopeno na sua estabilidade e biodisponibilidade." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-26092014-090346/.

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Licopeno, um pigmento natural considerado o mais potente antioxidante dentre os carotenoides, é oque tem maior incidência no soro humano. Seu consumo regular está relacionado principalmente com a prevenção do câncer de próstata. Porém, estudos também demonstram sua relação com a prevenção de câncer de pâncreas e bexiga, doenças cardiovasculares como a aterosclerose e doenças neurodegenerativas. Todavia, por ser altamente insaturado o licopeno é susceptível à degradação, sendo degradado na presença de luz, oxigênio e se exposto a altas temperaturas. A microencapsulação entra como uma alternativa para tentar garantir maior estabilidade a este carotenoide. A técnica de spray-chilling, por dispensar o emprego de altas temperaturas e solventes durante o processo de atomização, representa uma alternativa promissora na encapsulação do licopeno. Os objetivos deste trabalho foram encapsular uma solução oleosa de licopeno (10%) através da técnica de spray-chilling,utilizando gordura vegetal low trans como carreador, caracterizar as micropartículas obtidas e avaliar a biodisponibilidade do licopeno livre e encapsulado em ratos wistars. Foram formulados seis tratamentos, que diferiam pela concentração de solução comercial de licopeno, sendo T1 com 20%, T2 com 23,1%, T3 com 28,6%, T4 com 33,3%, T5 com 17,9% mais 10% de goma arábica e T6 com 19,2% mais 5% de carboximetilcelulose (CMC). As micropartículas obtidas destes tratamentos foram avaliadas quanto a tamanho e distribuição, morfologia por microscopia eletrônica de varredura (MEV), espectroscopia de infravermelho com transformadas de Fourier (FT-IR), difração de raios-X (DRX). A estabilidade do licopeno encapsulado foi avaliada em diferentes condições de armazenamento (sob vácuo, umidade relativa de 33%, temperatura de refrigeração e ambiente) e também foi determinada por meio de quantificações periódicas de licopeno, bem como através da análise análise da cor instrumental. A biodisponibilidade foi avaliada utilizando-se 68 animais divididos em grupos, para os quais se administrou por gavagem o licopeno livre e o encapsulado. O tamanho das micropartículas obtidas ficou em torno de 60-110 µm e a distribuição foi polidispersa, independente da concentração de licopeno. A microscopia revelou micropartículas esféricas, com superfície rugosa, com alguns poros e tamanhos variados. No FT-IR verificou-se que não houve formação de ligações distintas na solução oleosa de licopeno e nas amostras atomizadas. Nos difratogramas observou-se a presença da forma polimórfica β para o agente carreador e para as micropartículas. Na estabilidade a adição da goma arábica e o armazenamento sob temperatura de refrigeração e vácuo, foram as melhores condições para retardar a degradação do licopeno. Os resultados dos ensaios de biodisponibilidade foram inconclusivos. Desta forma, conclui-se que é possível encapsular licopeno através da técnica de spray-chilling, porém, para trabalhos futuros, seriam necessários aprimoramentos na técnica de encapsulação e/ou na formulação para conferir maior proteção ao carotenoide, bem como adequações na metodologia para determinação de sua biodisponibilidade, para obtenção de resultados conclusivos.
Lycopene, a natural pigment considered the most potent antioxidant among the carotenoids, it has the higher incidence in the human serum. Its regular consumption is mainly related with the prevention of prostate cancer. However, studies also show its relation to the prevention of pancreatic cancer and bladder cancer, cardiovascular diseases such as atherosclerosis and neurodegenerative diseases. However, by being highly unsaturated the lycopene is susceptible to degradation, being degraded in the presence of light, oxygen and if exposed to high temperatures. The microencapsulation comes like an alternative to ensuring higher stability for this carotenoid. The technique of spray-chilling represents a promising alternative to encapsulation of lycopene. The aims of this study were to encapsulate an oily solution of lycopene (10%) through of the technique of spray-chilling, using a low-trans fat as carrier, to characterize the obtained microparticles and to evaluate the bioavailability of lycopene free and encapsulated in Wistar rats. Six treatments were formulated, that differed by the content of oily solution of lycopene:T1 with 20%, T2 with 23.1%, T3 with 28.6%, T3 with 28.6%, T4 with 33.3%, T5 with 17.9% plus 10% of Arabic gum and T6 with 19.2% plus 5% of carboxymethylcellulose (CMC). The microparticles obtained from these treatments were evaluated for size and distribution, morphology by scanning electron microscopy (SEM), infrared spectroscopy with Fourier transform (FT-IR) and X-ray difraction (XRD). The stability of the lycopene encapsulated was evaluated by its periodic quantification at different storage conditions (vacuum, relative humidity of 33%, refrigeration temperature and environment temperature). Instrumental color, \"L\" and \"a\" parameters, also was measured. The bioavailability was evaluated using 68 animals, for which the free and lycopene encapsulated were administered by gavage. The size of microparticles obtained was around 60-110 µm and the distribution was polydisperse, independent of the concentration of lycopene. The microscopy revealed spherical microparticles, with rough surface, with some pores and varying sizes. In the FT-IR it was found that there was no formation of distinct bonds in oily solution of lycopeno and the atomized samples. In the diffraction patterns observed the presence of polymorphic form \"β\" for the carrier agent and microparticles. On the stability the addition of Arabic gum and the storage at refrigerator temperature under vacuum, were the best conditions to delay the degradation of lycopene. The results of bioavailability assays were inconclusive. As conclusion, it is possible to encapsulate lycopene using the technique of spray-chilling but to future works, would be required improvements in the technique of encapsulation and/or formulations to give more protection to the carotenoid, as well as adjustments in the methodology for determination of their bioavailability, in order to obtaining conclusive results.

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30

Lane, William D. "Spread spectrum multi-h modulation." Diss., Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/16944.

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31

Sheffield, Randolph J. "High heat flux spray cooling." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/17881.

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32

Kjettselberg, Marcus. "OC-Spray : Handhavande och bakgrund." Thesis, Umeå University, Basic training programme for Police Officers, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-27570.

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I denna rapport vill jag försöka belysa de fördelar och eventuella nackdelar med den OC-spray som svensk polis använder sig av. Tanken med den här rapporten är att man ska få reda på hur man gick till väga när man provade fram sprayen och på vilket sätt den är tänkt att hjälpa den enskilde polisen. En enkätundersökning har gjorts hos ordningspolisen i Linköping där en fingervisning ges om vad poliserna idag tycker om OC-sprayen. Jag har även genomfört kortare intervjuer med en OC-instruktör samt den ansvarige för rapporten Fältförsök OC (som även ligger till grund för större delen av mitt arbete).

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33

El-Helw, Amr M. "Pattern classification using spread spectrum." Thesis, Staffordshire University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.479162.

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34

Bewlay, B. P. "The spray forming of alloys." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382684.

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35

Goldberg, J. "Modelling of spray dryer performance." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376924.

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36

Grant, Patrick S. "Spray forming of aluminium alloys." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302790.

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37

Muhamad, N. "Modelling of spray forming process." Thesis, Swansea University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638270.

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This thesis reports the results of a theoretical investigation into the Osprey Preform Process. It focuses on the fluid and heat transfer phenomena associated with the liquid metal spray, the billet buildup and the solidification behaviour of the metal as the preform is produced. In the first part of the study, a nonlinear lumped parameter numerical model has been developed to model the physical processes taking place in the two phase spray and both fluid and thermal influences have been addressed. The analyses show the importance of the momentum exchange with the entrained gas on both velocity profiles and the temperature histories of the spray and this reflects the need to consider the total thermal design of the deposition chamber. The effect of a small amount of undercooling was also included where it was found to result in a wetter spray arriving at the deposit. The above model was incorporated in the buildup simulation for a cylindrical billet deposited onto a substrate having an axis in the horizontal plane. A series of sensitivity studies were carried out to assess the influence of some of the important chamber parameters which are mainly concerned with the position and movement of the scanner and the substrate under the spray. Although a direct comparison between the predicted billet shape and those manufactured was not posible due to the absence of data, the analyses confirmed the significant parameters which influence the billet shape produced and which have to be optimised in actual practice. These findings are compatible with the experience of Osprey Metal Ltd. Finally, the solidification history of the billet preform was analysed using a two dimensional thermal network method. It was found that the thermal history of the billet is sensitive to the thermal boundary conditions applied. Therefore, an appropriate choice of the spraying conditions needs to be established to produce uniform material properties throughout the billet extent.

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38

Bong, Felix Nyuk Poh. "Fire Spread on Exterior Walls." Thesis, University of Canterbury. Civil Engineering, 2000. http://hdl.handle.net/10092/8252.

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This report describes methods of predicting heat flux exposure to external walls due to the impingement of flame issuing through a window opening. A heat transfer model was set up for the purpose of predicting the geometry of the emerging flame and the resultant heat flux exposure to the wall surface. An existing flame spread model implemented in the BRANZFIRE model was selected for characterising the flame spread on exterior wall cladding materials, as a function of the heat flux exposure (from the projecting flame to the wall) and the material flammability properties of the wall material. Modifications were made to the flame spread model. The result was a prediction of rate and extent of the upward flame spread as a function of time and the heat release rate of the burning cladding material. It is concluded that the flame spread model has the potential to determine the flame spread characteristics associated with four different cladding materials. The flame spread model gave conservative prediction for three of the tested cladding materials. Overall, the heat transfer model seems to predict the total heat flux density received by the exposing wall with reasonable accuracy. Further validation of the heat transfer model is needed before it can be successfully integrated into the flame spread model to provide a useful tool for characterising flame spread and estimating the heat flux exposure conditions.

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39

Jing, Cao. "Spray diagnostics by laser diffraction." Thesis, University of Sheffield, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321852.

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40

Bai, Chengxin. "Modelling of spray impingement processes." Thesis, Online version, 1996. http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.299814.

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41

Mirzamohammadbonakdar, Tina. "Attrition of spray-dried powders." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/13350/.

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42

Mohd, Yasin Mohd Fairus Bin. "Modelling of biodiesel spray combustion." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648856.

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43

Slator, Duncan. "Fuel injector spray diagnostic development." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/17488.

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New technologies are constantly developing towards the goal of increasing the performance of gas turbine engines while reducing pollutant emissions. The design of the combustion system is vital in the drive to reduce pollutants in order to meet legislative targets. As part of this, the fuel injector is crucial in preparing the fuel for combustion through atomization and correct mixing with the air flow. Thus, it is desirable to develop techniques to allow the analysis of performance in these key criteria and improve the understanding of both fuel injector aerodynamics and fuel atomisation. Particle Image Velocimetry (PIV) allows for spatially resolved velocity data of flow fields to be recorded and therefore enables the inspection of flow behaviour.

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44

Siccha, Macassi Ana, and de Ugaz Olga Lock. "Secado por atomización (spray dryer)." Revista de Química, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/100576.

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45

Roy, Kirsty. "Spray deposition for plastic electronics." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/45287.

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Spray deposition is a promising technique for the solution processing of plastic electronic devices due to its potential for high-speed, large-scale device fabrication using low capital cost equipment. Most recent reports of spray-deposited electronic devices have used ultrasonic systems for film deposition to minimise surface roughness, but such systems suffer from low materials throughput, and are consequently ill-suited to industrial manufacturing. Gas-driven spray-heads enable higher throughput materials delivery but can result in an unacceptably rough film due to the large, broadly distributed droplet sizes that are often generated and the hard-impact nature of the deposition process. This thesis describes a new automated gas-driven spray coater for the controlled deposition of a broad variety of solution processed electronic materials. It is specifically suited to the deposition of polymer films such as poly(3-hexylthiophene) (P3HT), overcoming many of the usual disadvantages of conventional gas-driven spray coaters. Key features of the system include: a novel, high performance 3D-printed spray-head for the generation of ultrafine sprays; full three-dimensional position and velocity control of the spray head; integrated temperature control; and independent control of solution and gas flow rates. To determine the optimum solution composition for spray-deposition of P3HT films, the aggregation and gelation dynamics of various P3HT/o-xylene solutions were first investigated by static light scattering. On the basis of these measurements, we conclude that dilute solutions (with polymer concentration < 5 mg/ml) of low (< 20 kg/mol ) molecular weight polymer containing a small amount of a secondary solvent. are optimal for avoiding gelation and clogging of the spay-head. For higher weight material, heating of the solution is necessary to avoid gelation. The thesis also describes the development of an optical profiling technique for the characterisation of polymer films, which provides a fast method for quantitatively characterising the uniformity of large-area, thin polymer films. Using this technique, we were able to confirm that the spray-deposition system yields high quality, thin semiconducting polymer films, allowing for the controlled fabrication of active layers in organic photovoltaic devices from non-chlorinated solvents. The influence of solution composition and deposition variables such as gas pressure, solvent composition and substrate temperature were investigated, and optimised conditions for the deposition of high quality (device-grade) thin P3HT films were thereby identified. A maximum device efficiency of 4.0 % was achieved for the spray-deposited bulk heterojunction P3HT:fullerene films processed from xylene. The results indicate that, providing the active layer is continuous, high device efficiency may be achieved even with relatively rough films, spray-coated from non-chlorinated processing solvents.

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46

Enuguri, Venkata Kotaiah Shiva Teja, and Sri Harsha Karra. "Colliding Drops in Spray Dryers." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-17386.

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Spray drying is a process, which produces powders from the fluid state. This type of process is mostly used in the industrial sector. In this process, a liquid slurry is atomized, forming droplets, which are dried with hot air. During spray drying these droplets will interact and upon impact can show different types of interactions; droplet-droplet collisions as well as interactions with partially or completely dried particles, leading to agglomeration. The result of collision gives properties of the dried powder. The focus of the thesis is to investigate the droplet-droplet collision outcomes of WPC 80 (Whey Protein Concentrate 80) and Lactose. Then the effects of the absolute droplet diameter and the droplet diameter ratios are to be determined. Existing experimental setup and Image Processing Tool of MATLAB is used to study the collision outcome. The outcomes are shown in a regime map. The present results are compared with different products result and literature study. It is observed that there is an effect on collision outcome for different droplet size ratios and no effect for absolute droplet diameter.

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47

Popa, Gabriela. "Spray-on hybrid nanoscale coatings." Strasbourg, 2010. https://publication-theses.unistra.fr/public/theses_doctorat/2010/POPA_Gabriela_2010.pdf.

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Des couches minces hybrides ont été préparé par une version modifiée de la méthode classique de déposition « couches-par-couches ». Les couches inorganiques de ces films hybrides sont déposés en utilisant la méthode de pulvérisation consécutive (qui est la méthode modifiée) pour laquelle la pulvérisation de solutions aqueuses se fait de manière alterné avec des temps de pulvérisation très courts (moins de 5 secondes). Nombreuses couches inorganique sont obtenues par cette technique telles que des couches de phosphate de calcium, oxalate de calcium, fluorure de calcium, Blue de Prusse, chlorure d’argent, etc. L’application principale des couches hybrides contenant de phosphate de calcium et Collagène est la fabrication de nouveaux biomatériaux pour la régénération/réparation du cartilage articulaire (le domaine d’ingénierie tissulaire). La structure de type « sandwich » de ces components permet la mimique du cartilage articulaire naturel. Pour la préparation de ces couches hybrides on a utilisé un film mince de polyélectrolytes de (PAHPSS). Le dépôt de couche mince inorganique peut se faire aussi en utilisant la méthode de pulvérisation simultanée des deux solutions contenant les cations et les anions. Des couches minces homogènes sur des surfaces d’ordre des cm2 ont été obtenues et pour lesquelles l’épaisseur peut être contrôlée par la variation de paramètres de pulvérisation tels que le temps de pulvérisation, la concentration de la solution, la nature du substrat
Hybrid thin films were prepared by a modified variant of the classical Layer-by-Layer (LbL) deposition method. Inorganic coatings are deposited using the consecutive spray method, in which aqueous solutions are alternatingly sprayed for short times (less than 5 seconds). Numerous inorganic coatings were prepared this way such as calcium phosphate, calcium fluoride, calcium oxalate, silver chloride, Prussian Blue. The main target of the hybrid films comprised of calcium phosphate and Collagen is for application in the cartilage repair. “Sandwich”-like structures of these components mimic the natural articular cartilage structure. In order to obtain the hybrid film containing Collagen and calcium phosphate, we used a (PAHPSS)barrier film. The deposition of inorganic coating can also be realized using the simultaneous spraying method where both solutions (cationic and anionic solution) are sprayed simultaneously. Homogeneous on several cm2 of surface thin films are obtained in which the film thickness is controlled by spray parameters such as spraying time, solution concentration, nature of substrate to be coated

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48

Majhool, Ahmed Abed Al-Kadhem. "Advanced spray and combustion modelling." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/advanced-spray-and-combustion-modelling(eb3ef22a-53d0-4e70-aa9d-bec37775d451).html.

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The thesis presents work across three different subjects of investigations into the modelling of spray development and its interaction with non-reactive and reactive flow. The first part of this research is aimed to create a new and robust family of convective scheme to capture the interface between the dispersed and the carrier phases without the need to build up the interface boundary. The selection of Weighted Average Flux (WAF) scheme is due to this scheme being designed to deal with random flux scheme which is second-order accurate in space and time. The convective flux in each cell face utilizes the WAF scheme blended with Switching Technique for Advection and Capturing of Surfaces (STACS) scheme for high resolution flux limiters. However in the next step, the high resolution scheme is blended with the scheme to provide the sharpness and boundedness of the interface by using switching strategy. The proposed scheme is tested on capturing the spray edges in modelling hollow cone type sprays without need to reconstruct two-phase interface. A test comparison between TVD scheme and WAF scheme using the same flux limiter on convective flow on hollow cone spray is presented. Results show that the WAF scheme gives better prediction than the TVD scheme. The only way to check the accuracy of the presented models are evaluations according to physical droplets behaviour and its interaction with air. In the second part, due to the effect of evaporation the temperature profile in the released fuel vapour has been proposed. The underlying equation utilizes transported vapour mass fraction. It can be used along with the solution of heat transfer inside a sphere. After applying boundary conditions, the equation can provide a solution of existing conditions at liquid-gas interface undergoing evaporation and it is put in a form similar to well-known one-third rule equation. The resulting equation is quadratic type that gives an accurate prediction for the thermo-physical properties due to the non-linear relation between measured properties and temperature. Comparisons are made with one-third rule where both equations are implemented in simulating hollow cone spray under evaporation conditions. The results show the presumed equation performs better than one-third rule in all comparisons. The third part of this research is about a conceptual model for turbulent spray combustion for two combustion regimes that has been proposed and tested for n-heptane solid cone spray type injected into a high-pressure, high-temperature open reactor by comparing to the available experimental data and to results obtained using two well known combustion models named the Combined Combustion Model (CCM) and the unsteady two-dimensional conditional moment closure (CMC) model. A single-zone intermittent beta-two equation turbulent model is suggested to characterise the Lumped zone. This model can handle both unburned and burned zones. Intermittency theory is used to account for the spatially non-uniform distribution of viscous dissipation. The model suggests that the Lumped zone can be identified by using the concept of Tennekes and Kuo-Corrsion of isotropic turbulence that suggests that dissipative eddies are most probably formed as vortex tubes with a diameter of the order of Kolmogorov length scale and a space of the order of Taylor length scale. Due to the complexity of mixture motion in the combustion chamber, there exist coherent turbulent small scale structures containing highly dissipative vortices. The small size eddies play an important role in extinguishing a diffusion spray flame and have an effect on the combustion reaction at molecular scale because small scales turbulence increase heat transfer due to the dissipation. A common hypothesis in constructing part of the model is if the Kolmogorov length scale is larger than the turbulent flame thickness. The Lumped strategy benefits from capturing small reactive scales information provided by numerics to improve the modelling and understand the exact implementation of the underlying chemical hypothesis. The Lumped rate is estimated from the ratio of the turbulent diffusion to reaction flame thickness. Three different initial gas temperature test cases are implemented in simulations. Lumped spray combustion model shows a very good agreement with available experimental data concerning auto-ignition delay points.

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49

Gao, Xuan. "Drop impact in spray cooling." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/63356.

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Spray cooling has enormous potential in addressing high-heat-flux thermal challenges in many cutting-edge technologies. In spray cooling, a flow of coolant drops is emitted from a spray nozzle and impacts a hot surface, which is covered by a flowing film. Heat transfers by convection from the surface to the liquid coolant, and the cooling performance is determined by the fluid dynamics of spray drops impacting the liquid film. The cooling mechanisms involved in spray cooling are still not clear, due to the lack of understanding of the heat transfer and fluid dynamics involved in the drop impact in spray cooling. The research work puts focus on the drop impact in spray cooling, which is carried out in four major steps. The first step is to study spray impact cooling experimentally with focus on the cooling effects of nozzle positioning parameters including spray height and inclination angle. The positioning parameters are shown to have effects on global and local cooling as the drop impact is affected when changing the spray positioning. The second step is to experimentally and theoretically investigate the fluid dynamics of a single liquid drop impacting a flowing film. The third step is to evaluate heat transfer enhancement during a single drop impact. The work carried out in the second and third steps forms a comprehensive study on the thermal-fluidics of single drop impact on a flowing film. The fourth step moves on to the heat transfer enhancement of drop train impacting flowing films. A drop train is formed when drops are generated in groups, and each group has a consistent number of drops. A drop generator is combined with a special setup to generate drop trains with varied impact frequencies including group frequency (the generation rate of groups) and single frequency (the generation rate of single drops in each group). The results relate the cooling enhancement of continuous drop impact to important impact parameters including drop number, velocity, and impact frequencies.
Applied Science, Faculty of
Engineering, School of (Okanagan)
Graduate

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50

Rashid, Shaan. "Dual-spray Synthesis and Reactions." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35726.

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By using two electrospray emitters containing different solutions (“dual-spray”) we have recently conducted in-source hydrogen/deuterium exchange (HDX) reactions and synthesized organometallic species. For dual-spray HDX reactions, peptide and protein solutions were electrosprayed through one emitter and the deuterating agent D2O through the secondary electrospray emitter. Clear shifts in isotope distributions indicated hydrogen-deuterium exchange occurring within the ion source. By ion mobility, simultaneous deuterium exchange for two isobaric species, the oxytocin monomer and dimer, was observed. Lysozyme has a linear relation between the charge state and the average number of exchanges, indicating that lysozyme becomes increasingly unfolded as the charge state increases. Based on deuterium uptake data and the lack of a temperature dependence, the dual-spray HDX reaction is thought to occur mostly in the gas phase. Tris(2,2’-bipyridine)ruthenium(II) and similar complexes containing the 1,10-phenanthroline ligand were formed by spraying a ligand solution and the ruthenium trichloride solution through two independent ESI emitters. This was confirmed by comparing ion mobility drift time, mass spectra, and CID fragmentation with the reference standard compounds. Tris(2,2’-bipyridine)iron(II), tris(1,10-phenantroline)iron(II) and mixed ligand complexes of iron(II) formed by dual-spray showed two additional hydrogens bonded to the complex. By CID, these unique gas phase complexes showed similar initial ligand loss to the reference standards however the secondary ligand loss showed dissimilar dissociation channels and energetics. Using DFT calculations, geometry optimizations for the [Fe(phen)3 + 2H]2+ complex and its fragment ions were done. After the initial ligand loss, the additional hydrogens are believed to transfer to the central iron atom. The relative energy of the dissociation channels showed good agreement with experimental breakdown curves.

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