OBD-etälukulaite

Tämä insinöörityö tehtiin osana startup-yritys Servoped Oy:n tuotekehitystä. Työn tavoitteena oli suunnitella ja toteuttaa laite, jolla voidaan kommunikoida henkilöajoneuvon kanssa käyttäen ajoneuvon OBD-väylää. Laitteeseen haluttiin myös etäohjauksen mahdollisuus. Työssä käydään läpi suunnittelun eri vaiheet ja valmiille laitteelle asetetut vaatimukset. Haasteena työssä oli suunnitella laite siten, että sillä kerättävää dataa voitaisiin käyttää hyvällä hyötysuhteella. Varsinainen ohjelmiston suunnittelu suoritettiin Arduino ohjelmointiympäristössä, jota työssä käytetty Hologram Dash -mikrokontrolleri tukee. Ajoneuvon kiihtyvyystietoja tallennettiin erillisellä kiihtyvyys anturilla, joka on kytketty Hologram Dash -mikrokontrolleriin. Lopputuloksena syntyi toimiva OBD-etälukulaite, joka on muokattavissa ja laitteen konfiguraatiota voidaan muuttaa etäohjauksella. Laitteen keräämä data lähetään ensin Amazonpalvelimelle, josta data siirretään Heroku-palvelinympäristöön, jossa data tarjotaan asiakkaille räätälöidyssä muodossa.This engineering thesis was carried out as part of product development at the startup company Servoped Oy. The aim of this thesis was to design and implement a device that can communicate with a passenger vehicle using the OBD-connection of the vehicle. Remote connection to the device was implemented. This thesis examines the various stages of designing a new product and the requirements for the finished product. The challenge was to determine such specifications for the deviceto be able to provide useful data. The actual software design was carried out in the Arduino programming environment which is supported by the Hologram Dash -microcontroller. Vehicle acceleration data was recorded with a separate acceleration sensor connected to the Hologram Dash -microcontroller. The result was a fully functional OBD-device that is customizable and remote controlled. The data collected by the OBD-device is first sent to Amazon-server and then routed to Heroku-server which is where the data is offered to customers in appropriate format

Kullan sähkökemiallinen liukeneminen kupari- ja rautakloridiliuoksissa

Currently, gold is produced predominantly by the cyanide leaching process. However, there is a demand for alternative methods to replace cyanidation, mainly due to environmental concerns. Chloride leaching has been suggested as one of the most promising cyanide-free processes due to its high leaching rates, high metal solubility, and the possibility to dissolve refractory minerals without pre-treatment. The phenomena of gold dissolution in cupric and ferric chloride leaching are not fully understood, and there is still no commercialized gold chloride leaching process operating on industrial scale. The three main objectives of the thesis were as follows: i) to investigate the electrochemical behavior of gold dissolution in cupric and ferric chloride solutions, ii) to determine the dependency between the redox potential, open circuit potential (OCP), and gold dissolution rate in order to build a tool to estimate gold dissolution in cupric and ferric chloride solutions, and iii) to verify the gold dissolution rate determined by electrochemical experiments using an industrial raw material in cupric chloride solution. The electrochemical test methods included linear polarization resistance, polarization (Tafel method), and cyclic voltammetry measurements. Additionally, quartz crystal microbalance measurements were performed to define the dissolution rate. It is suggested that gold dissolves through direct oxidation by metallic chloride complexes to aurous gold, i.e., AuCl2–, in the investigated cupric (T = 28–95 °C, [Cu2+] = 0.02–1.0 M, [Cl–] = 1.0–5.0 M, pH = 0.0–2.0, and ω = 100–2500 RPM), and ferric (T = 25–95 °C, [Fe3+] = 0.02–1.0 M, [Cl–] = 2.0–5.0 M, pH = 0.0–1.0, and ω = 100–2500 RPM) chloride solutions. It is posited that AuCl2– species do not oxidize to AuCl4– species; however, the formation of AuCl4– through a disproportionation reaction is possible. An increase in temperature, oxidant, and chloride concentration, as well as rotational speed (i.e., mass transfer) promoted the gold dissolution rate, but the pH did not show any clear effect on cupric and ferric chloride leaching in the investigated conditions. Ferric chloride leaching of gold resulted in higher redox potentials, OCPs, and dissolution rates than cupric chloride leaching. It was found that the redox potential could be used to estimate the gold dissolution rate, since it had a positive linear correlation with the logarithm of the gold dissolution rate. Additionally, the redox potential could be defined from the values of the process variables. However, it was found that the OCP could not be used as a single parameter to estimate the gold dissolution rate, as the correlation between the OCP and the logarithm of the gold dissolution rate was insignificant. Batch leaching experiments with a gold-containing tailing verified the results of the electrochemical experiments in cupric chloride solutions. The effect of process variables on the gold dissolution rate was clearer in the electrochemical tests; however, the same trends of parameters and their impacts were also visible in the batch leaching tests.Syanidiliuotus on nykyisin hallitseva menetelmä kullan valmistusprosessissa, mutta etenkin ympäristösyiden takia vaihtoehtoisia prosesseja on tutkittu syanidiliuotuksen korvaajaksi. Kloridiliuotusta pidetään yhtenä lupaavimmista syanidivapaista prosesseista, ja sen etuina ovat korkeat liuotusnopeudet, korkea metallien liukoisuus ja kyky liuottaa vaikeasti liukenevia mineraaleja ilman esikäsittelyä. Kaikkia ilmiöitä kullan liukenemisesta kupari- ja rautakloridiliuoksissa ei vielä tiedetä, eikä teollisuudessa ole käytössä yhtään kaupallistettua kullan kloridiliuotusprosessia. Väitöskirjan kolme tavoitetta olivat: i) kullan sähkökemiallisen liukenemisen selvittäminen kupari- ja rautakloridiliuoksissa, ii) redox-potentiaalin, korroosiopotentiaalin ja kullan liukenemisnopeuden välisen suhteen määritys, jotta voitaisiin mallintaa ja ennustaa kullan liukenemista kupari- ja rautakloridiliuoksissa sekä iii) sähkökemiallisten kokeiden liuotusnopeuksien todentaminen teollisella raaka-aineella kuparikloridiliuoksissa. Käytettyihin sähkökemiallisiin tutkimusmenetelmiin kuuluivat polarisaatiovastuksen mittaus, polarisaatiokäyrät ja niiden tulkinta Tafelin menetelmällä sekä syklisellä voltametrialla. Lisäksi kullan liukenemisnopeutta mitattiin kvartsikidemikrovaa'alla. Tulosten perusteella kulta liukenee AuCl2−-komplekseina sekä kuparikloridiliuoksissa (T = 28–95 °C, [Cu2+] = 0.02–1.0 M, [Cl–] = 1.0–5.0 M, pH = 0.0–2.0 ja ω = 100–2500 RPM) että rautakloridiliuoksissa (T = 25–95 °C, [Fe3+] = 0.02–1.0 M, [Cl–] = 2.0–5.0 M, pH = 0.0–1.0 ja ω = 100–2500 RPM). Tutkimuksen perusteella AuCl2−-ionit eivät hapetu suoraan AuCl4−-ioneiksi, mutta niitä voi muodostua disproportionaatioreaktion kautta. Kullan liukenemisnopeus kasvoi, kun lämpötilaa, hapetin- ja kloridipitoisuutta tai aineensiirron nopeutta kasvatettiin, mutta pH:lla ei ollut vaikutusta. Rautakloridiliuotuksessa saatiin aikaan korkeammat arvot redox-potentiaalille, korroosio-potentiaalille ja liuotusnopeudelle kuin kuparikloridiliuotuksessa. Redox-potentiaalia pystyttiin käyttämään ennustamaan kullan liukenemisnopeutta, koska niiden välillä havaittiin lineaarinen riippuvuus. Lisäksi redox-potentiaali pystyttiin mallintamaan ja kuvaamaan prosessiparametrien avulla. Korroosiopotentiaalia ei pystytty käyttämään kullan liukenemisnopeutta ennustamisessa heikon korrelaation vuoksi. Panosliuotuskokeissa rikastusjätteellä todennettiin sähkökemiallisten kokeiden tulokset kuparikloridiliuotuksessa. Samankaltaiset prosessiparametrien vaikutukset olivat havaittavissa myös panosliuotuskokeissa, mutta vaikutukset olivat heikompia kuin sähkökemiallisissa kokeissa synteettisissä liuoksissa

Pathways of dyslexic students towards university : Resources and agency of dyslexic university student

Tiivistelmä – Abstrakt – Abstract Tavoitteet. Lukivaikeuksia diagnosoidaan nykyään aikaisempaa enemmän kehittyneiden testimenetelmien ansiosta. Aikaisemmissa tutkimuksissa on todettu, että lukivaikeuksiset opiskelijat eivät yleensä hakeudu korkeampaan koulutukseen. Tutkimuksen tarkoituksena on selvittää, mitkä tekijät ovat mahdollistaneet joidenkin lukivaikeuksisten opiskelijoiden hakeutumisen yliopistoon lukivaikeudesta huolimatta ja miten lukivaikeuksiset opiskelijat saataisiin integroitua koulutusjärjestelmään paremmin. Tutkimuksessa selvitettiin, miten lukivaikeuksisten opiskelijoiden koulutuspolut ovat muodostuneet, mitkä resurssit ovat kannatelleet opiskelijoita sekä miten opiskelijoiden toimijuus on kehittynyt opintopolun aikana. Lisäksi resurssien yhteyttä toimijuuteen tutkittiin. Toimijuutta tutkittiin opintohistorian, vallitsevan ympäristön sekä tilannekohtaisen toimijuuden näkökulmista. Resurssit jaettiin käytännön, symbolisiin ja tapojen resursseihin. Menetelmät. Tutkimuksen aineisto kerättiin haastattelemalla viittä suomalaista lukivaikeustaustaista yliopisto-opiskelijaa, jotka suorittivat peruskouluna 1997–2011 välisenä aikana. Haastatteluilla kerätyt kertomukset sijoittuivat narratiivisen periaatteen mukaisesti opiskelijoiden koulun aloituksen ajankohdasta tämänhetkiseen yliopisto-opintojen vaiheeseen. Aineiston keruussa yhdistyi narratiivinen haastattelu ja teemahaastattelu. Kerronnallisen haastattelun tuottamat kertomukset eli narratiivit analysoitiin mukaillen holistista sekä temaattista narratiivien analyysiä. Tulokset ja johtopäätökset. Tutkimus osoitti, että opiskelijoiden opintohistoriat erosivat toisistaan, vaikka kaikkien opiskelijoiden koulutuspolku on kulkenut pääpiirteittäin samansuuntaisesti. Myös lukivaikeuksisten opiskelijoiden toimijuus muuttui ja kehittyi koulutuspolulla edetessä, etenkin toimijuuden osa-alueiden merkitys ja keskinäinen suhde vaihteli. Resursseilla havaittiin olevan suora yhteys opiskelijoiden toimijuuteen, kun resurssien määrä tai suuruus oli kasvanut, myös toimijuus oli vahvistunut sekä päinvastoin. Opiskelijat olivat onnistuneet kääntämään lukivaikeuden resurssiksi vahvistuneen itsetunnon, lukivaikeusmyönteisyyden ja selkeän oman elämänkaaren sekä vahvuuksiensa ja heikkouksiensa tuntemisen avulla. Johtopäätökseksi laadittiin neliosainen toimintalista, jolla pystyttäisiin integroimaan lukivaikeuksiset opiskelijat osaksi koulujärjestelmäämme. Lukivaikeus tulisi diagnosoida mahdollisimman aikaisin, jotta opiskelijan tarvitsemaa tukea osattaisiin kohdistaa hänelle jo koulutuspolun alusta lähtien. Opiskelijoita tulisi rohkaista myös paljastamaan lukivaikeutensa opintopolulla, jotta heidän ottaminen osaksi kouluyhteisöä onnistuisi paremmin. Lisäksi lukivaikeutta koskevan tiedon määrää tulisi lisätä kaikilla koulutusasteilla, jolloin myös sen diagnosointi helpottuisi ja lukivaikeuden paljastaminen olisi opiskelijalle helpompaa, kun lukivaikeuteen suhtauduttaisiin myönteisemmin. Lisäämällä tietoa lukivaikeudesta ja sen vaikutuksista, voitaisiin lukivaikeusmyönteisyyttä kasvattaa. Viimeiseksi, koulumaailmaan tulisi luoda yhteiset toimintaohjeet, sekä niiden ja käytännön toteutuksen välistä suhdetta tulisi valvoa ja arvioidaAim of the study. Nowadays, dyslexias are diagnosed more often compared to previous times due to advanced test methods. According to previous studies, dyslexic students are not often applying for higher education. The aim of this work was to define features that have made it possible for few dyslexic students to get in university despite the dyslexia and how dyslexic students could be integrated better into education system. In this study, it was determined, how the pathways of dyslexic students are composed, which resources of students had assisted them and how the agency of students had developed through school pathway. Further, the connection between resources and agency was investigated. The agency was investigated from the point of views of education history, prevailing environment and active agency. Resources were classified into practical resources, resources of meanings and symbols as well as resources of habits and practices. Used methods. The research data was collected by interviewing five Finnish dyslexic university students, who attended comprehensive school between years 1997 and 2011. Narrations, collected with interviews, included the school pathway from starting school to current period in university. Narrations were analyzed with holistic and thematic narrative research method. Results and conclusions. It was found that the education histories of students differed, though the pathways of students were mostly similar. In addition, the agencies of dyslexic students changed and developed through their pathways, especially the meaning and relation of different pieces of agencies varied. It was found that resources had dependency on the agency of students, since the increase in amount or volume of resources resulted in enhanced agency, and contrariwise. The students were able to turn their dyslexia into resource due to their strengthen self-esteem, pro-dyslexia, clear knowledge of their career as well as their strengths and weaknesses. As conclusions, quadripartite activity guide was formed in order to integrate dyslexic students into our education system. Dyslexia should be diagnosed as early as possible in order to provide students with required support already from the start of their pathways. Further, dyslexic students should also be encouraged to reveal their dyslexia in order to integrate them better into school society. Additionally, knowledge of dyslexia should be increased in every school stage in order to ease diagnosing of dyslexia and revealing of it, when the attitude towards dyslexia would be more positive. By increasing knowledge of dyslexia and its effects, pro-dyslexia could be enhanced. Finally, general action guides should be created as well as the relation of action guide and their actions in practice should be supervised and evaluate

Effect of redox potential and OCP in ferric and cupric chloride leaching of gold

The research presented contributes to the global goal of responsible production by providing robust tools for the optimization of gold dissolution in cyanide-free gold leaching solutions, which represent emerging non-toxic gold technologies. In the current study, gold dissolution was investigated in ferric and cupric chloride solutions. The effect of the redox potential on the open circuit potential (OCP) and dissolution rate of gold was investigated experimentally in the parameter range of T = 25–95 °C, [Fe3+/Cu2+] = 0.02–1.0 M, [Cl−] = 1–5 M, pH = 0.0–2.0, and ωcyc = 2500 RPM. A high rotational speed was chosen to minimize the effects of limited mass transfer rate. The aim was to provide tools for estimating the gold dissolution rate in ferric and cupric chloride solutions, using the solution properties. The results showed that redox potentials, OCPs, and dissolution rates were constantly higher in ferric chloride solutions compared to corresponding cupric chloride solutions. The multilinear regression models for redox potential showed that a rise in temperature and oxidant concentration increased the redox potential in both ferric and cupric chloride solutions. However, an increase in the chloride concentration decreased the redox potential in ferric chloride solutions, whereas the effect was the opposite in cupric solutions. A rise in the pH value increased the redox potential in ferric solutions, but this was found to be an insignificant variable in cupric chloride leaching within the investigated parameter range. The redox potential had a positive correlation with OCP and the logarithm of the gold dissolution rate in both investigated systems. The results suggest that, in the chloride leaching systems examined, the solution properties can be used to determine the redox potential, and furthermore, the redox potential can be used to estimate the gold dissolution rate. This study provides an experimentally verified tool for the robust estimation of the gold dissolution rate in chloride systems.Peer reviewe

Features affecting the cupric chloride leaching of gold

The current study investigated gold dissolution in cupric chloride solution, which is one of the most promising alternatives to replace cyanide, although not yet in operation on industrial scale. In this paper, the gold dissolution reaction rate and mechanism were studied by varying the process variables of temperature (28–95 °C), cupric concentration (0.02–1.0 M), chloride concentration (1–5 M), rotational speed (100–2500 RPM), and pH (0.5–2.0). The parameters affecting either the anodic or cathodic reaction, or both, were identified for the first time to the best of the authors’ knowledge in this wide range and with these parameter intervals. Tafel and linear polarization methods as well as cyclic voltammetry were used for pure gold with both rotating disk and stationary gold electrodes. An increase in the gold dissolution rate was observed with an increase in temperature, chloride concentration, and rotational speed. Additionally, an increase in cupric concentration ([Cu 2+ ] = 0.02–0.75 M) promoted the gold dissolution rate, whereas the gold dissolution rate decreased with [Cu 2+ ] from 0.75 to 1.0 M. The conditions for maximizing the gold dissolution rate in cupric chloride solution were concluded to be T > 55 °C, [Cu 2+ ] = 0.5–0.75 M, [Cl − ] = 5 M, and pH = 1.0 and the highest gold dissolution rate (2.9 · 10 −4 mol m −2 s −1 ) was achieved at 95 °C with [Cu 2+ ] = 0.5 M, [Cl − ] = 5 M, pH = 1.0, and ω cyc = 2500 RPM. The pH was shown not to affect the gold dissolution rate at all, but only to affect the solubility of the oxidant. It was suggested that gold dissolved as aurous species in the conditions of this study, although the increase in chloride concentration promoted the dissolution of gold as both, auric and aurous, species. The reaction mechanism was interpreted using mixed potential theory. An increase in temperature was shown to promote only the cathodic reduction of cupric ion to cuprous at lower temperatures (28–55 °C); however, both the anodic gold dissolution reaction and cathodic cupric reduction reaction were enhanced at higher temperatures (65–95 °C). The cathodic reaction was also enhanced with an increase in cupric concentration (0.02–0.5 M), whereas the anodic reaction was promoted when the cupric concentration was increased from 0.5 to 0.75 M. When the cupric concentration was increased from 0.75 to 1.0 M, the cathodic reaction rate decreased. However, the reason for the decrease in the cathodic reaction rate was not clear. An increase in chloride concentration enhanced the cathodic reaction in the investigated range (1–5 M), whereas an increase in rotational speed (i.e., improved mass transfer) increased the anodic gold dissolution rate, specifically at low rotational speeds.Peer reviewe

Direct Cupric Chloride Leaching of Gold from Refractory Sulfide Ore

Funding Information: The authors would like to thank the Emil Aaltonen Foundation for financially supporting the “Sustainable gold” project. The study was also supported by GoldTail (Grant No. 319691), funded by the Academy of Finland, and the Finnish Foundation for Technology Promotion. This work was also supported by “RawMatTERS Finland Infrastructure” (RAMI) by the Academy of Finland. Publisher Copyright: © 2021 The Author(s). Published with license by Taylor & Francis Group, LLC. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.A simulation-based life cycle assessment was conducted to compare the impacts of different cyanide-free chloride processing routes for refractory ores to determine whether one-stage leaching of gold from the ores could be advantageous over chloride leaching after conventional pressure oxidation from an environmental perspective. It was shown that both leaching conditions and the refractoriness of the ore strongly affect the environmental impacts of the process. The global warming potential in the direct leaching route was determined to vary between 7.7–17.0 t CO2-eq for 1 kg gold/Au. Prerequisites for the sustainable application of the direct leaching process are suggested.Peer reviewe

A study on selective leaching of heavy metals vs. iron from fly ash

Incinerator plant waste streams contain underexploited metals originating from households and industrial operators. The objective was to investigate the dissolution behavior of fly ash in: 0.2–7 M HCl, 0.2–7 M H 2 SO 4 , 0.5–1 M oxalic acid, 0.5–4 M citric acid, 0.5–7 M acetic acid, water, and ethaline, at 33 °C during 24 h leaching. The capability for high metals’ extraction of Zn, Cu, Ni, Pb, and Fe and management of the heavy metal Pb through leaching or precipitation was investigated. Selective leaching of valuable metals vs. Fe was observed. The target was to find a sustainable leaching method and provide a basis for further development of metal recovery from fly ash. The highest Zn extraction (> 80%) was achieved with 3 M H 2 SO 4 and 7 M HCl, which also dissolved Cu (> 87%) and Ni (> 65%). However, more dilute HCl, 0.2 M, was able to provide Zn, Cu, and Ni extractions of 43, 86, and 18%, respectively. Efficient Pb leaching was achieved in HCl—complete extraction was provided by 3 and 5 M HCl, whereas H 2 SO 4 did not extract Pb due to PbSO 4 formation; similarly, in oxalic acid, Pb precipitated as PbC 2 O 4 . Ethaline could extract 50% of Pb with high selectivity towards Fe.Peer reviewe