Use of the Optical Cantilever Microphone in Photoacoustic Spectroscopy

A novel cantilever pressure sensor was developed in the Department of Physics at the University of Turku in order to solve the sensitivity problems which are encountered when condenser microphones are used in photoacoustic spectroscopy. The cantilever pressure sensor, combined with a laser interferometer for the measurement of the cantilever movements, proved to be highly sensitive. The original aim of this work was to integrate the sensor in a photoacoustic gas detector working in a differential measurement scheme. The integration was made successfully into three prototypes. In addition, the cantilever was also integrated in the photoacoustic FTIR measurement schemes of gas-, liquid-, and solid-phase samples. A theoretical model for the signal generation in each measurement scheme was created and the optimal celldesign discussed. The sensitivity and selectivity of the differential method were evaluated when a blackbody radiator and a mechanical chopper were used with CO₂, CH4, CO, and C2H4 gases. The detection limits were in the sub-ppm level for all four gases with only a 1.3 second integration time and the cross interference was well below one percent for all gas combinations other than those between hydrocarbons. Sensitivity with other infrared sources was compared using ethylene as an example gas. In the comparison of sensitivity with different infrared sources the electrically modulated blackbody radiator gave a 35 times higher and the CO2-laser a 100 times lower detection limit than the blackbody radiator with a mechanical chopper. As a conclusion, the differential system is well suited to rapid single gas measurements. Gas-phase photoacoustic FTIR spectroscopy gives the best performance, when several components have to be analyzed simultaneously from multicomponent samples. Multicomponent measurements were demonstrated with a sample that contained different concentrations of CO₂, H₂O, CO, and four different hydrocarbons. It required an approximately 10 times longer measurement time to achieve the same detection limit for a single gas as with the differential system. The properties of the photoacoustic FTIR spectroscopy were also compared to conventional transmission FTIR spectroscopy by simulations. Solid- and liquid-phase photoacoustic FTIR spectroscopy has several advantages compared to other techniques and therefore it also has a great variety of applications. A comparison of the signal-to-noise ratio between photoacoustic cells with a cantilever microphone and a condenser microphone was done with standard carbon black, polyethene, and sunflower oil samples. The cell with the cantilever microphone proved to have a 5-10 times higher signal-to-noise ratio than the reference detector, depending on the sample. Cantilever enhanced photoacoustics will be an effective tool for gas detection and analysis of solid- and liquid-phase samples. The preliminary prototypes gave good results in all three measurement schemes that were studied. According to simulations, there are possibilities for further enhancement of the sensitivity, as well as other properties, of each system.

Métodos Ultravioleta Selectivo y de reducción con Hidracina en la determinación del ión nitrato an aguas subterraneas

In this study, a comparison of two methods, the Selective UV Spectrophotometrical Method and Reduction with Hidrazine Method, for the determination of Nitrate ion in groundwater, was carried out. For this purpose, the results from all the drinking water collectings of the city of Olavarría, Argentina, were employed. Both methods present significant different means, but they don´t present significant differences in their variances.

Experimentos didáticos envolvendo radiação microondas

Theoretical and practical aspects of the use of microwave-assisted strategies in chemistry are introduced for students using simple and safe experiments employing a domestic oven. Three procedures are proposed for evaluating the distribution of microwave radiation inside the microwave oven cavity: (1) variation of the volume of marshmallows; (2) drying of filter paper wetted with Co(II) solution, and (3) variation of water temperature, after microwave-assisted heating. These experiments establish the position with the highest incidence of microwave radiation in the oven cavity, which was chosen for the synthesis of salicylic acid acetate. This synthesis was performed in 5 min of heating and the yield was around 85%. All experiments can be carried out in a 4 h lab-session using low-cost instrumentation.

Produção de hidrogênio a partir da reforma a vapor de etanol utilizando catalisadores Cu/Ni/gama-Al2o3

Cu/Ni/gamma-Al2O3 catalysts were prepared by an impregnation method with 2.5 or 5% wt of copper and 5 or 15% wt of nickel and applied in ethanol steam reforming. The catalysts were characterized by atomic absorption spectrophotometry, X-ray diffraction, temperature programmed reduction with hydrogen and nitrogen adsorption. The samples showed low crystallinity, with the presence of CuO and NiO, both as crystallites and in dispersed phase, as well as of NiO-Al2O3. The catalytic tests carried out at 400 ºC, with a 3:1 water/ethanol molar ratio, indicated the 5Cu/5Ni/Al2O3 catalyst as the most active for hydrogen production, with a hydrogen yield of 77% and ethanol conversion of 98%.

Controllerilta vaadittavat ominaisuudet ja keskeisimmät työtehtävät - casetutkimus

Tutkimuksen tavoitteena oli selvittää, millaiset ovat controllereiden työtehtävät ja controllereilta vaadittavat ominaisuudet tänä päivänä. Teoreettisena taustana tutkimuksessa oli johdon laskentatoimen kehitys 1980-luvulta tähän päivään. Tutkimus toteutettiin kvalitatiivisin menetelmin analysoimalla tänä vuonna julkaistuja suomalaisia ja ruotsalaisia controller-rekrytointi-ilmoituksia ja haastattelemalla henkilökohtaisesti controllerin työtehtävissä työskenteleviä henkilöitä useilta toimialoilta. Tutkimuksen keskeisimpänä tuloksena havaittiin, että yrityksen työpaikkailmoituksissa vaadittavissa ominaisuuksissa on eroavaisuuksia suhteessa haastattelussa painotettuihin ominaisuuksiin. Ilmoituksissa mainitut controllereiden työtehtävät olivat enemmän linjassa todellisten työtehtävien kanssa. Sekä työpaikkailmoituksissa että haastatteluissa kävi ilmi, että controllerin työtehtävä sisältää useasti edelleen ulkoiseen laskentaan liittyviä työtehtäviä. Tämä viittaa siihen, että controller-nimikkeen käyttö ei ole vielä vakiintunut vastaamaan johdon laskentatoimen tehtäviä. Controllereiden haastatteluissa nousi esiin useita controller-toiminnon kehityskohteita. Tutkimuksen johtopäätöksenä todettiin, että controllerin työtehtävien ja ominaisuuksien kehittämiseen ovat vaikuttaneet johdon laskentatoimen tietojärjestelmien kehitys, uudet laskentainnovaatiot ja controllerin roolinmuutos kohti strategista liiketoiminnan tukijaa. Yritysten controller-toimintoa ei ole haastatteluiden perusteella kuitenkaan vielä organisoitu vastaamaan tätä roolinmuutosta, joten controllerit kokivat, että heillä ei ole riittävästi aikaa analysointityöhön. Lisäksi controllereiden yhteistyötä kollegojen ja sidosryhmien kanssa pitäisi lisätä ja controller-toiminto tulisi tuoda lähemmäs liiketoimintaa.

Plasma polymerized acetaldehyde thin films for retention of volatile organic compounds

The aim of this work is the production and characterization of plasma polymerized acetaldehyde thin films. These films show highly polar species, are hydrophilic, organophilic and easily adsorb organic reactants with CO radicals but only allow permeation of reactants with OH radicals. The good step coverage of films deposited on aluminum trenches is useful for sensor development. Films deposited on hydrophobic substrates may result in a discontinued layer, which allows the use of preconcentration in sample pretreatment. Deposition on microchannels showed the possibility of chromatographic columns and/or retention system production to selectively detect or remove organic compounds from gas flows.

Simultaneous determination of Cd and Pb in antibiotics used in sugar-cane fermentation process by GFAAS

A method has been developed for the simultaneous determination of Cd and Pb in antibiotics used in sugar-cane fermentation by GFAAS. The integrated platform of transversely heated graphite atomizer was treated with tungsten to form a coating of tungsten carbide. Six samples of commercial solid antibiotics were analyzed by injecting 20 µL of digested samples into the pretreated graphite platform with co-injection of 5 µL of 1000 mg L-1 Pd as chemical modifier. Samples were mineralized in a closed-vessel microwave-assisted acid-digestion system using nitric acid plus hydrogen peroxide. The pyrolysis and atomization temperatures of the heating program of the atomizer were selected as 600°C and 2200°C, respectively. The calculated characteristic mass for Cd and Pb was 1.6 pg and 42 pg, respectively. Limits of detection (LOD) based on integrated absorbance were 0.02 µg L-1 Cd and 0.7 µg L-1 Pb and the relative standard deviations (n = 10) for Cd and Pb were 5.7% and 8.0%, respectively. The recoveries of Cd and Pb added to the digested samples varied from 91% to 125% (Cd) and 80% to 112% (Pb).

Organisaatioiden ostokäyttäytyminen yliopistollisen aikuiskoulutuksen hankinnassa

Tutkimuksen toimeksiantaja on Lappeenrannan teknillisen yliopiston Koulutus- ja kehittämiskeskus. Tutkimuksen tavoitteena on selvittää miten yliopiston asiakasorganisaatioiden hankintapäätös muodostuu. Pääpaino tutkimuksessa on päätöksentekoyksikön ja päätöksentekokriteerien kartoittamisessa. Teoriaosuus koostuu työn kannalta keskeisimmistä aikuiskoulutuspalveluiden sekä organisaation ostokäyttäytymisen teorioista. Tutkimuksessa käytetään sekä kvalitatiivisia, että kvantitatiivisia tutkimusmenetelmiä. Pääpaino on haastattelututkimuksella ja aineisto analysoidaan laadullisin menetelmin. Otanta koostuu kahdeksasta asiakasorganisaatiosta ja kahdeksasta organisaatiosta, joiden kanssa toivotaan yhteistyötä. Yritykset ovat toimeksiantajan asiakasmatriisista. Tutkimuksen perusteella saatiin selkeä kuva yritysten koulutuksen hankinnasta. Henkilöstön kouluttaminen koetaan yrityksissä tärkeäksi ja siihen panostetaan paljon. Merkittävästi päätöksentekoon yrityksessä ottavat osaa koulutusvastaava ja henkilöstöhallinto. Päätös muodostetaan yhteistyössä asiantuntijan kanssa, joka on usein liiketoimintayksikön esimies. Merkittävimmät päätöksentekoon vaikuttavat kriteerit selkiytyivät koulutuksen tarjoajan, koulutuksen sekä hankintaprosessin osalta sekä asiakasorganisaatioissa että potentiaalisissa yrityksissä. Vaikka tutkimustulosten ja toimenpide-ehdotusten raportointi tapahtuu tässä tutkimuksessa yleisellä tasolla, saa Koulutus- ja kehittämiskeskus tutkimuksen konkreettiset tulokset kuten kontaktoitavat henkilöt, päätöksentekoyksikön jäsenet sekä päätöksentekokriteerit kussakin yrityksessä omaan yksityiseen käyttöönsä. Päätöksentekokriteerit ovat hyödyksi erityisesti toivottavien potentiaalisten organisaatioiden vaatimusten ymmärtämisessä.

Työssäjaksamisen voimavarat ja työssä jatkaminen ikääntyneillä vanhusten hoitotyötä tekevillä

Tässä pro gradu –tutkielmassa tarkasteltiin ikääntyneiden vanhusten hoitotyötä tekevien työssäjaksamista ja työssä jatkamissuunnitelmia voimavarakeskeisestä näkökulmasta käsin. Kiinnostuksen kohteena olivat myös työyhteisön suhtautuminen ikääntyvään työvoimaan ja keinot, joilla ikääntyneiden työssä jatkamista ja jaksamista tuetaan organisaatiossa. Tutkimusta varten haastateltiin kymmentä yli 55-vuotiasta vanhusten hoitotyötä tekevää henkilöä. Johtopäätösten mukaan työn voimavaroista merkittävimmiksi työssäjaksamisen ja työssä jatkamisen kannalta nousivat hyvät suhteet työtovereihin, toimiva työyhteisö ja asiakkaat. Työn ulkopuolisesta elämästä voimia saatiin mielekkäistä vapaa-ajan puuhista ja läheisistä. Persoonallisuuden voimavaroista keskeiseksi nousi optimistisuus. Eläkkeellä työskentelyaikomusten taustalla olivat usein kokemus työstä nauttimisesta ja hyvä terveys. Toisaalta hyvästä terveydestä haluttiin nauttia myös eläkkeellä.

Interfirm Information System for Supply Chain Management from the Cloud: An Exploratory Case Study from the Telecom Industry

This study examines the practice of supply chain management problems and the perceived demand information distortion’s (the bullwhip effect) reduction with the interfirm information system, which is delivered as a cloud service to a company operating in the telecommunications industry. The purpose is to shed light in practice that do the interfirm information system have impact on the performance of the supply chain and in particularly the reduction of bullwhip effect. In addition, a holistic case study of the global telecommunications company's supply chain is presented and also the challenges it’s facing, and this study also proposes some measures to improve the situation. The theoretical part consists of the supply chain and its management, as well as increasing the efficiency and introducing the theories and related previous research. In addition, study presents performance metrics for the bullwhip effect detection and tracking. The theoretical part ends in presenting cloud -based business intelligence theoretical framework used in the background of this study. The research strategy is a qualitative case study, supported by quantitative data, which is collected from a telecommunication sector company's databases. Qualitative data were gathered mainly with two open interviews and the e-mail exchange during the development project. In addition, other materials from the company were collected during the project and the company's web site information was also used as the source. The data was collected to a specific case study database in order to increase reliability. The results show that the bullwhip effect can be reduced with the interfirm information system and with the use of CPFR and S&OP models and in particularly combining them to an integrated business planning. According to this study the interfirm information system does not, however, solve all of the supply chain and their effectiveness -related problems, because also the company’s processes and human activities have a major impact.

Yrittäjyyskasvatus yhteistyöverkostoissa

Tutkimus käsittelee Yrittäjyyskasvatuksen Mittariston -projektia, jossa tutkimuskohteena on peruskoulun ensimmäisen asteen luokan- ja aineenopettajien näkemys ja kokemus yrittäjyyskasvatuksen verkostoyhteistyöstä. Tutkimuksen tarkoituksena oli selvittää miten hyvin opettajat tuntevat verkostoyhteistyötä, mikä on heidän tietämyksensä yrittäjyyskasvatuksesta ja kuinka tämä näkyy heidän työssään ja opetuksessaan. Tutkimuksen otos on 450 opettajaa. Tulokset analysoitiin SPSS-tilastomenetelmäohjelmalla. Tilastollisina tutkimusmenetelminä käytettiin jakaumien frekvenssianalyysiä, Faktori­analyysin Pääkomponenttianalyysiä ja Kaksisuuntaista varianssianalyysia (Anova). Tutkimuksen johtopäätöksenä voidaan todeta, että opettajien tiedot yhteistyö-verkostojen tarjoamista palveluista ovat hyvin hajanaiset. Ongelma jatkuu helposti niin kauan kunnes opettajien koulutusohjelmaan tuodaan lisää yrittäjyyskasvatus- ja yrittäjyysopintoja. Tämä pitäisi huomioida myös tulevissa opetussuunnitelmissa. Tämän tutkimuksen tavoitteena oli tuoda esille Yrittäjyyskasvatuksen mittariston tulosten kautta yrittäjyyskasvatuksen nykytila, tuoda ratkaisuja ehdotusten kautta opetukseen ja herättää keskustelua yrittäjyyskasvatuksen parantamiseksi.

Addition of anacardic acid as antioxidants in broiler chicken mortadella

AbstractThe effect of anacardic acid on lipid stability and coloration of chicken mortadella was investigated. Antioxidants were added to chicken mortadellas, according to the treatments: no added antioxidant, 100 ppm butylated hydroxytoluene and 50, 100, 150 and 200 ppm anacardic acid. The mortadellas were stored for 90 days at 4 °C, and the analysis of lipid oxidation and color were performed. For TBARS, there was linear reduction with increased anacardic acid. According to the means test, 200 ppm anacardic acid provided the lower TBARS values. The redness decreased during storage, and, as reported by the means test, mortadella containing 200 ppm anacardic acid had lower values. The lightness of mortadellas decreased during storage. Also in accordance with the means test, mortadellas containing antioxidants had same lightness than control. The yellowness of mortadellas increased during storage. Thus, the anacardic acid is a potential natural antioxidant that could be included in chicken mortadella formulations before cooking.

Investigations towards the synthesis of isotope labelled analogues of tocopherols and tocotrienols /

Vitamin E is considered as the most effective lipophilic chain breaking antioxidant. a-Tocopherol and its analogues have been studied thoroughly with regards to its biokinetics and bioavailabily. Deuterated tocopherols have been synthesized and utilized in such studies. Tocotrienols are arousing more and more interest because of their high efficiency as antioxidants. However, to date, there is no effective synthetic method reported for deuterated tocotrienols. This thesis is focused on the investigation of the synthetic methods of deuterated tocotrienols and their analogues: 5-trideuteromethyl-a-tocotrienol, 5- trideuteromethyl-p-tocotrienol, tocotrienol acetate, silyl tocotrienol ether, etc. Several synthetic procedures for the preparation of poly-deuterated tocopherols are known. Mainly the deuterium is introduced by use of labelled formaldehyde and deuterated hydrogen chloride under Lewis acid catalysis. However, these methods are not effective in tocotrienols due to exchange of protons for deuterium at other sites under the acidic conditions. We developed several different approaches to generate polydeuterated tocotrienols by using both morpholinomethylation followed by reduction with NaCNBDs as deuterated reducing reagents and transmetalation strategy. The 5-trideuteromethyl-a-tocotrienol was finally obtained in a satisfactory yield of 60%. In addition, this thesis also discussed the study of structural comparison and the chemical property difference of tocopherols and tocotrienols, which provides hints to explain the reactivity difference of them towards oxidation at the C3-C4 positions.Furthermore, the methodology of halogenation and dehydrohalogenation of tocotrienol was explored to prepare a hexaene tocotrienol derivative as a florescent reporter of tocopherol.

An aryne route to aporphine alkaloids and related topics / |nIjaz Ahmad Chanda. -- 260 St. Catharines, Ont. : [s. n.],

This research was directed towards the investigation and development of an aryne route to the syntheses of aporphi ne and dibenzopyrrocolinium (dibenzoindolizinium) alkaloids and to the stability of the latter under the conditions used for aryne formation. The work c an be divided into three main sections . i) - Synthesis of Glaucine 6-Bromo-3,4-dimethoxyphenylacetic acid, prepared by the action of bromine i n acetic acid on3,4-dimethoxyphenylacetic a cid, was converted into its acid chloride by t he action of thionyl chloride. This on treatment with 3,4- dimethoxyphenylethylamine pr ovided N-(3, 4-dimethoxyphenylethyl)- 2-(2-bromo-4,S-dimethoxyphenyl)-acetamide which on dehydration with phosphoryl chloride (Bischler Napieralski reaction) in dry benzene afforded l -(2-bromo-4,S-dimethoxybenzyl)- 3,4-dihydro-6,7-dimethoxyisoquinoline, isolated as hydrochl oride. A new method o f destroying the excess of phosphoryl chloride was developed which proved to be quite useful. Methylation of the dihydroisoquinoline'with methyl iodide in methanol , and subsequent reduction with sodium borohydride provided (±)-6-bromolaudanosine. Act ion of potassamide or sodamide in anhydrous liquid ammonia on (±)-6-bromolaudanosine yielded the corresponding amino derivative along with other products. Diazotization and ring closure of (±)-6-aminolaudanosine then a f forded (±)-glaucine which was isolated as methiodide. ii) - Intramolecular Capture of Aryne During Glaucine Synthesis, and Subsequent Reactions . This section deals with the by-products formed under the conditions of the aryne stage of t he glaucine synthesis. The crude product, obtained in the reaction of potassamide or sodamide in liquid ammonia on (±)-6-bromolaudanosine, was s eparated by chromatography, Three products were separated and identified. a ) - 5,6-Dimethoxy-2-( 3,4-dimethoxy-6-ethylphenyl)-lmethylindole. Two mechanisms are proposed for the formation of this interesting product. This compound also was prepared by the action of potassamide in l,iquid ammonia on 5,6 ,l2,l2atetrahydro- 2,3,9,lO-tetramethoxy-7-methyldibenz[b,g]indolizinium i odide . b) - 5,6-Dimethoxy-2-(3,4-dimethoxy-6-vinylphenyl)-lmethylindoline. Its formation represented a new method of Hofmann degradation . Further confirmation of structure was done by performing the normal Hofmann reaction on 5, 6,12,12a-tetrahydro -2/3,9,lO-tetramethoxy ~7-methyldibe nz[ b,g]indolizinium iodide. The indoline prepared i n this way was identical in all respects with that prepared above . c) - 1- (2-amino-4,5-dimethoxybenzyl ) -l,2,3,4-tetrahydro-2- methyl-6,7-dimethoxyisoquinoline, was converted t o glaucine as stated in section 1 . iii) - Attempt:,ed Sxnthesis of Liriodenine Piperonal was converted into 3,4-methylenedioxyinitrostyrene which on reduction with lithium aluminium hydride provided 3,4-methylenedioxyphenylethylamine. The method of extraction after the reduction was improved t o some extent. The amine on condensation with m-chlorophenylacetyl chloride, prepared by the action of oxalyl chloride on 3,4-methylenedioxyphenylacetic acid, provided N-[ ~ -(3,4-methylenedioxyphenyl)- e thyl)-3-chlorophenylacetamide. This on dehydration with phosphoryl chloride in dry benzene followed by air oxidation afforded l-(3-chlorobenzoyl)-6,7-methylenedioxyi soquinoline. This compound on r eaction with potassamide in liquid ammonia afforded a crude product from which. one product was separated by chromatography i n a pure condition . This yellow compound analysed as,c17Hl ON2021 and was t he main product i n the reaction ; a t entative structure is proposed. A second compound, not obtained in pure condition, was submitted to Pschorr reaction in the hope of obtaining liriodenine, but without success.

Test of Hockman and Oldham's job characteristics model in a post-secondary educational setting

One hundred and seventy-two subj ects participated in this quantitative, correlational survey which tested Hackman and Oldham's Job Characteristics Model in an educational setting. Subjects were Teaching Masters, Chairmen and Deans from an Ontario community college. The data were collected via mailed questionnaire, on all variables of the model. Several reliable, valid instruments were used to test the variables. Data analysis through Pearson correlation and stepwise multiple regression analyses revealed that core job characteristics predicted certain critical psychological states and that these critical psychological states, in turn were able to predict various personal and work outcomes but not absenteeism. The context variable, Satisfaction with Co-workers, was the only consistent moderating variable between core characteristics and critical psychological states; however, individual employee differences did moderate the relationship between critical psychological states and all of the personal and work outcomes except Internal Work Motivation. Two other moderator variables, Satisfaction with Context and Growth Need Strength, demonstrated an ability to predict the outcome General Job Satisfaction. The research suggests that this model may be used for job design and redesign purposes within the community college setting.