150 research outputs found
Clinical utility of folate-containing oral contraceptives [Corrigendum]
No full textLassi ZS, Bhutta ZA. International Journal of Women’s Health. 2012;4:185–190.On page 185, Burden of neural tube defects and its natural history section, 3rd paragraph, 1st sentence, note that "estimated incidence of 4,300,000 new cases a year" should have been "estimated incidence of >300,000 new cases a year".On page 189, Reference 2 was listed as Jegatheesan P, Keller RL, Hawgood S. Early variable-flow nasal continuous positive airway pressure in infants ≤1000 grams at birth. J Perinatol. 2006;26(3):189–196.The correct reference is Shibuya K, Murray CJL. Congenital anomalies. In: Murray CJL, Lopez AD, eds. Health Dimensions of Sex and Reproduction: The Global Burden of Sexually Transmitted Diseases, HIV, Maternal Conditions, Perinatal Disorders, and Congenital Anomalies. Vol. 3. Boston, MA: Harvard University Press, 1998:455–512.Read the original articl
Author response to: Cardiovascular risk factors in offspring exposed to gestational diabetes mellitus in utero: systematic review and meta-analysis
No full textLetter to the EditorThis commentary is an author response to Yu and colleagues regarding the manuscript entitled ‘Cardiovascular risk factors in offspring exposed to gestational diabetes mellitus in utero: Systematic review and meta-analysis’. We address their concern regarding minor errors in our manuscript, our search strategy and assessment of heterogeneity.Maleesa M. Pathirana, Zohra S. Lassi, Claire T. Roberts, and Prabha H. Andraweer
Radiotherapy for localised Ewing’s sarcoma in children
No full textUmer M, Qadir I, Abbasi N, Das JK, Lassi ZS. Radiotherapy for localised Ewing\u27s sarcoma in children. Cochrane Database of Systematic Reviews 2014, Issue 5. Art. No.: CD011105. DOI: 10.1002/14651858.CD011105. ... Radiotherapy for localised Ewing\u27s sarcoma in children (Protocol) Copyright © 2014 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. ... Radiotherapy for localised Ewing\u27s sarcoma in children (Protocol) Copyright © 2014 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd
Preparation of circular economy-based adsorbents and their usage for wastewater treatment in batch and fixed bed columns
No full textAbstract
Industrial wastewater contains harmful contaminants like ammonium, heavy metals (e.g. nickel, cobalt, zinc), and cationic dyes (e.g. methylene blue), posing environmental and health risks. This study develops cost-effective, eco-friendly alkali-activated adsorbents for wastewater treatment from industrial side-streams (analcime and steel industry slags), activated with sodium hydroxide and sodium silicate or potassium silicate. Experiments were designed to assess the effectiveness of these adsorbents in removing wastewater pollutants. Initially, the efficiency of removing ammonium ion pollutants from aqueous solutions was tested, and the results (29.79 mg/g) were used as guidance in refining the synthesis conditions of the adsorbents to optimize their structural and chemical properties to ensure more effective adsorption capacities. The batch experiments demonstrated the rate of ammonium ions captured by the adsorbent surface and the interaction between the adsorbent and ammonium ions provides insight into the efficiency of the process under controlled experimental conditions.
Continuous fixed-bed column studies were then conducted to investigate the performance of the adsorbents under various conditions and to simulate practical wastewater treatment scenarios and evaluate the effectiveness of a continuous flow system. The fixed-bed columns demonstrated the adsorption behavior of multiple contaminants and the adsorption capacity was 3.26 mg/g, 13.92 mg/g, 6.86 mg/g, 6.39 mg/g and 18.9 mg/g for ammonium, zinc, cobalt, nickel and cationic dyes, respectively. The results showed that alkali-activated adsorbents were highly effective among the pollutants studied. The adsorbents´ reusability was evaluated by a regeneration study and the results confirmed their pollutant removal capacity over different cycles. Adsorbents preserved their pollutant removal capacity over successive regeneration experiments. This demonstrated stability highlights their potential for repeated use in continuous wastewater treatment operations and illuminates their economic and environmental advantages. Overall, the findings validated the effectiveness of alkali-activated adsorbents synthesized from industrial side-streams in wastewater treatment. Original papers Runtti, H., Sundhararasu, E., Pesonen, J., Tuomikoski, S., Hu, T., Lassi, U., & Kangas, T. (2023). Removal of ammonium ions from aqueous solutions using alkali-activated analcime as sorbent. ChemEngineering, 7(1), 5. https://doi.org/10.3390/chemengineering7010005 https://doi.org/10.3390/chemengineering7010005 Self-archived version Sundhararasu, E., Tuomikoski, S., Runtti, H., Hu, T., Varila, T., Kangas, T., & Lassi, U. (2021). Alkali-activated adsorbents from slags: Column adsorption and regeneration study for nickel(II) removal. ChemEngineering, 5(1), 13. https://doi.org/10.3390/chemengineering5010013 https://doi.org/10.3390/chemengineering5010013 Self-archived version Sundhararasu, E., Runtti, H., Kangas, T., Pesonen, J., Lassi, U., & Tuomikoski, S. (2022). Column adsorption studies for the removal of ammonium using Na-zeolite-based geopolymers. Resources, 11(12), 119. https://doi.org/10.3390/resources11120119 https://doi.org/10.3390/resources11120119 Self-archived version Sundhararasu, E., Runtti, H., Kangas, T., Lassi, U., & Tuomikoski, S. (2025). Slag-based alkali-activated adsorbent for efficiently removing ternary heavy metals and dye in wastewater. Manuscript in preparation. Tiivistelmä
Teollisuuden jätevedet sisältävät haitallisia epäpuhtauksia, kuten ammoniumia, raskasmetalleja (esim. nikkeli, koboltti, sinkki) ja kationisia väriaineita (esim. metyleenisininen), jotka aiheuttavat ympäristö- ja terveysriskejä. Tässä tutkimuksessa kehitettiin kustannustehokkaita ja ympäristöystävällisiä alkaliaktivoituja adsorbentteja jäteveden käsittelyyn hyödyntämällä teollisuuden sivuvirtoja (analsiimi ja terästeollisuuden kuonat). Kokeissa testattiin adsorbenttien tehokkuutta jäteveden epäpuhtauksien poistamisessa. Aluksi testattiin ammoniumionien poistotehokkuutta vesiliuoksista ja tulosten (29,79 mg/g) pohjalta muokattiin adsorbenttien synteesiolosuhteita niiden rakenteellisten ja kemiallisten ominaisuuksien optimoimiseksi tavoitteena parantaa materiaalin adsorptiokykyä. Panoskokeet osoittivat nopean ja tehokkaan ammoniumin adsorboinnin kontrolloiduissa koeolosuhteissa.
Kolonnikokeet simuloivat käytännön olosuhteita jätevedenpuhdistuksessa. Kolonnikokeet osoittivat useiden epäpuhtauksien, kuten ammoniumionien, raskasmetallien ja kationisen väriaineen, poistotehokkuuden. Adsorptiokapasiteetti oli 3,26, 13,92, 6,86, 6,39 ja 18,9 mg/g ammoniumin, sinkin, koboltin, nikkelin ja väriaineen poistossa. Adsorbenttien uudelleenkäytettävyys arvioitiin regenerointitutkimuksella. Tulokset vahvistivat adsorbentin epäpuhtauksien poistokapasiteetin useilla adsorptio-desorptiosykleillä. Adsorbentit säilyttivät epäpuhtauksien poistokykynsä peräkkäisten regenerointikokeiden aikana. Adsorbentin käytettävyys useissa sykleissä osoittaa taloudellisia ja ympäristöllisiä etuja.
Yhteenvetona tutkimus vahvistaa, että teollisuuden sivuvirroista syntetisoidut alkaliaktivoidut adsorbentit ovat tehokas ratkaisu jäteveden käsittelyyn. Adsorptiokyky ammoniumille, raskasmetalleille ja väriaineille oli suuri. Näiden tulosten ohella adsorbenttien tehokas regenerointi osoitti mahdollisuudet teollisuuden jätevesien käsittelyyn ympäristöystävällisellä ja kustannustehokkaalla tavalla. Osajulkaisut Runtti, H., Sundhararasu, E., Pesonen, J., Tuomikoski, S., Hu, T., Lassi, U., & Kangas, T. (2023). Removal of ammonium ions from aqueous solutions using alkali-activated analcime as sorbent. ChemEngineering, 7(1), 5. https://doi.org/10.3390/chemengineering7010005 https://doi.org/10.3390/chemengineering7010005 Rinnakkaistallennettu versio Sundhararasu, E., Tuomikoski, S., Runtti, H., Hu, T., Varila, T., Kangas, T., & Lassi, U. (2021). Alkali-activated adsorbents from slags: Column adsorption and regeneration study for nickel(II) removal. ChemEngineering, 5(1), 13. https://doi.org/10.3390/chemengineering5010013 https://doi.org/10.3390/chemengineering5010013 Rinnakkaistallennettu versio Sundhararasu, E., Runtti, H., Kangas, T., Pesonen, J., Lassi, U., & Tuomikoski, S. (2022). Column adsorption studies for the removal of ammonium using Na-zeolite-based geopolymers. Resources, 11(12), 119. https://doi.org/10.3390/resources11120119 https://doi.org/10.3390/resources11120119 Rinnakkaistallennettu versio Sundhararasu, E., Runtti, H., Kangas, T., Lassi, U., & Tuomikoski, S. (2025). Slag-based alkali-activated adsorbent for efficiently removing ternary heavy metals and dye in wastewater. Manuscript in preparation. Academic dissertation to be presented with the assent of the Doctoral Programme Committee of Technology and Natural Sciences of the University of Oulu for public defence in the Arina auditorium (TA105), Linnanmaa, on 4 December 2025, at 12 noonAbstract
Industrial wastewater contains harmful contaminants like ammonium, heavy metals (e.g. nickel, cobalt, zinc), and cationic dyes (e.g. methylene blue), posing environmental and health risks. This study develops cost-effective, eco-friendly alkali-activated adsorbents for wastewater treatment from industrial side-streams (analcime and steel industry slags), activated with sodium hydroxide and sodium silicate or potassium silicate. Experiments were designed to assess the effectiveness of these adsorbents in removing wastewater pollutants. Initially, the efficiency of removing ammonium ion pollutants from aqueous solutions was tested, and the results (29.79 mg/g) were used as guidance in refining the synthesis conditions of the adsorbents to optimize their structural and chemical properties to ensure more effective adsorption capacities. The batch experiments demonstrated the rate of ammonium ions captured by the adsorbent surface and the interaction between the adsorbent and ammonium ions provides insight into the efficiency of the process under controlled experimental conditions.
Continuous fixed-bed column studies were then conducted to investigate the performance of the adsorbents under various conditions and to simulate practical wastewater treatment scenarios and evaluate the effectiveness of a continuous flow system. The fixed-bed columns demonstrated the adsorption behavior of multiple contaminants and the adsorption capacity was 3.26 mg/g, 13.92 mg/g, 6.86 mg/g, 6.39 mg/g and 18.9 mg/g for ammonium, zinc, cobalt, nickel and cationic dyes, respectively. The results showed that alkali-activated adsorbents were highly effective among the pollutants studied. The adsorbents´ reusability was evaluated by a regeneration study and the results confirmed their pollutant removal capacity over different cycles. Adsorbents preserved their pollutant removal capacity over successive regeneration experiments. This demonstrated stability highlights their potential for repeated use in continuous wastewater treatment operations and illuminates their economic and environmental advantages. Overall, the findings validated the effectiveness of alkali-activated adsorbents synthesized from industrial side-streams in wastewater treatment.Tiivistelmä
Teollisuuden jätevedet sisältävät haitallisia epäpuhtauksia, kuten ammoniumia, raskasmetalleja (esim. nikkeli, koboltti, sinkki) ja kationisia väriaineita (esim. metyleenisininen), jotka aiheuttavat ympäristö- ja terveysriskejä. Tässä tutkimuksessa kehitettiin kustannustehokkaita ja ympäristöystävällisiä alkaliaktivoituja adsorbentteja jäteveden käsittelyyn hyödyntämällä teollisuuden sivuvirtoja (analsiimi ja terästeollisuuden kuonat). Kokeissa testattiin adsorbenttien tehokkuutta jäteveden epäpuhtauksien poistamisessa. Aluksi testattiin ammoniumionien poistotehokkuutta vesiliuoksista ja tulosten (29,79 mg/g) pohjalta muokattiin adsorbenttien synteesiolosuhteita niiden rakenteellisten ja kemiallisten ominaisuuksien optimoimiseksi tavoitteena parantaa materiaalin adsorptiokykyä. Panoskokeet osoittivat nopean ja tehokkaan ammoniumin adsorboinnin kontrolloiduissa koeolosuhteissa.
Kolonnikokeet simuloivat käytännön olosuhteita jätevedenpuhdistuksessa. Kolonnikokeet osoittivat useiden epäpuhtauksien, kuten ammoniumionien, raskasmetallien ja kationisen väriaineen, poistotehokkuuden. Adsorptiokapasiteetti oli 3,26, 13,92, 6,86, 6,39 ja 18,9 mg/g ammoniumin, sinkin, koboltin, nikkelin ja väriaineen poistossa. Adsorbenttien uudelleenkäytettävyys arvioitiin regenerointitutkimuksella. Tulokset vahvistivat adsorbentin epäpuhtauksien poistokapasiteetin useilla adsorptio-desorptiosykleillä. Adsorbentit säilyttivät epäpuhtauksien poistokykynsä peräkkäisten regenerointikokeiden aikana. Adsorbentin käytettävyys useissa sykleissä osoittaa taloudellisia ja ympäristöllisiä etuja.
Yhteenvetona tutkimus vahvistaa, että teollisuuden sivuvirroista syntetisoidut alkaliaktivoidut adsorbentit ovat tehokas ratkaisu jäteveden käsittelyyn. Adsorptiokyky ammoniumille, raskasmetalleille ja väriaineille oli suuri. Näiden tulosten ohella adsorbenttien tehokas regenerointi osoitti mahdollisuudet teollisuuden jätevesien käsittelyyn ympäristöystävällisellä ja kustannustehokkaalla tavalla
Incomplete democratization and conflict: The role of territory and nationalism
No full textThis dissertation explores the impact of incomplete democratic transitions on international peace and security. Since the end of the Second World War, the number of democracies has seen a five-fold increase. Countries do not, however, magically transform into fully institutionalized democracies overnight. I ask how ongoing democratic transitions impact the likelihood of international conflict and the ability of states to resolve disagreements peacefully. I advance a nuanced argument, suggesting that democratization leads to belligerent foreign policies, but only in contexts where territory is a salient point of contention between states. The presence of territorial issues allows political actors to use nationalistic rhetoric and, therefore, they will pursue hardline policies vis-à-vis other states. I find support for my argument in statistical analyses, using existing data on territorial issues and militarized disputes in an innovative way, as well as qualitative case studies. Notably, the process described here does not appear to be present when states contend over non-territorial issues, supporting the argument that there is a unique link between democratization, territorial issues, and nationalismSubmission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2020-12-01The student, Leif Lassi, accepted the attached license on 2018-11-30 at 13:46.The student, Leif Lassi, submitted this Dissertation for approval on 2018-11-30 at 13:50.This Dissertation was approved for publication on 2018-12-02 at 11:34.DSpace SAF Submission Ingestion Package generated from Vireo submission #13163 on 2019-02-07 at 14:18:42Made available in DSpace on 2019-02-07T20:36:05Z (GMT). No. of bitstreams: 2
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Clinical utility of folate-containing oral contraceptives
No full textZohra S Lassi, Zulfiqar A BhuttaDivision of Women and Child Health, The Aga Khan University, Karachi, PakistanAbstract: Folate is a generic term for a water-soluble B-complex vitamin which plays an important role in protein synthesis and metabolism and other processes related to cell multiplication and tissue growth. Pregnant and lactating women are at increased risk of folic acid deficiency because generally their dietary folate is insufficient to meet their physiological requirements and the metabolic demands of the growing fetus. The evidence pertaining to the reduction of the risk of neural tube defects (NTDs) due to folate is so compelling that supplementation with 400 µg of folic acid to all women trying to conceive until 12 weeks of pregnancy has been recommended by every relevant authority. A recent Cochrane review has also found protective effects of folate supplementation in occurrence and reoccurrence of NTDs. Despite food fortification and targeted public health campaigns promoting folic acid supplementation, 4,300,000 new cases occur each year worldwide resulting in an estimated 41,000 deaths and 2.3 million disability-adjusted life years (DALYS). This article will review the burden and risk factors of NTDS, and the role of folate in preventing NTDs. It will also describe different modes of supplementing folate and the newer evidence of the effectiveness of adding folate in oral contraceptives for raising serum and red blood cell folate levels.Keywords: folate, folate-containing oral contraceptives, oral contraceptives, contraceptive
Toiminnanohjauksen kehittäminen yritykselle X
No full textTIIVISTELMÄ
Tekijä(t): Mehtonen Lassi
Työn nimi: Toiminnanohjauksen kehittäminen yritykselle X
Tutkintonimike: Teknologia osaamisen johtaminen
Asiasanat: Toiminnanohjaus, ERP-järjestelmät, C-CEI menetelmä
Tämän opinnäytetyön tavoitteena oli kehittää Yrityksen X toiminnan-ohjausta. Tutkimuksella selvitettiin yrityksen toiminnanohjauksen kehittämisen tarpeita. Tutkimusaineisto on kerätty haastattelemalla kaikkia yrityksen henkilöstöryhmiä ylimmästä johdosta työntekijöihin. Lisäksi toimintaa havainnoitiin ja yrityksen dokumentaatio tutkittiin.
Tutkimusaineistoa analysoitiin Tampereen teknillisen yliopiston kehittämää C-CEI menetelmää soveltaen. C-CEI analyysin tuloksena saatiin kartoitettua kohdeyrityksen toiminta-, toimintaym-päristö- ja riskianalyysi. Näiden pohjalta yritykselle valittiin toiminnanohjausjärjestelmä ja perus-tettiin siihen nimikkeistö. Lisäksi opinnäytetyössä laadittiin kehittämisehdotukset tuotetiedon hallinnan parantamiseksi ja nykyisten toimintojen ja toiminnanohjausjärjestelmän logiikan yh-teensovittamiseksi.
Toiminnanohjausjärjestelmähankkeet liittyvät aina yrityksen liiketoiminnan kehittämiseen. Nämä hankkeet ovat hyvin laajoja. Tutkimuksen viitekehyksessä on kuvattu tässä opinnäyte-työssä kehitettäviä asioita.
Tutkimuksella saatiin yksityiskohtaista tietoa yrityksen toiminnasta. Ilman tätä tietoa toiminnan-ohjauksen kehittäminen olisi lähes mahdotonta. Tutkimusta voidaan hyödyntää tuotannollisen yritysten vastaavanlaisissa kehittämisprojekteissa.ABSTRACT
Author(s): Mehtonen Lassi
Title of the Publication: Development of resources planning for the Enterprise X
Degree Title: Technology Competense Management
Keywords: Operations management, ERP systems, C-CEI method
The goal of this study is to develop resources planning in the Enterprise X. First, the study looked into the development needs, processes and aims of the Enterprise X. The data was elicited by interviewing members of the personnel from the management level to the regular workers. In addition, operations at the Enterprise X were observed and the enterprise’s docu-mentation was used as data.
The data was analysed applying the C-CEI method designed by the Tampere University of Technology. The method comprises three analyses: operational, contextual, and risk analysis. On the basis of the results gained from these, a suitable ERP system was chosen for the En-terprise and the product naming/coding procedure was carried out. In addition, the study sug-gests means to improve product data management and to align current operations and pro-cesses with the ERP system and its logic.
Investment in an ERP system always aims at improving business processes in the enterprise. It is a huge project. In research framework described things that have been developed in this thesis.
This study yielded detailed information on the processes and operations at the Enterprise X. This information is of vital importance for the development of resources planning. The results can also be utilized in similar development projects in other manufacturing enterprise
LASSI's Great Adventure: A Meta-Analytic Review of the Learning and Study Strategies Inventory and Academic Outcomes
No full textThere have been considerable efforts to describe, examine, and foster the strategies students use while learning. Defined as thoughts, behaviors, beliefs, or emotions that facilitate knowledge acquisition, learning strategies play an essential role in students’ achievement. This study reports on a random-effects meta-analysis of 158 studies (2,897 effect sizes; N = 71,852 students) on relationships between learning and study strategies, as measured by ten subscales of an established and prevalent instrument, the Learning and Study Strategies Inventory (LASSI; Weinstein et al., 1987, 2004, 2016), and academic outcomes measured as GPA/grades, test scores, and persistence. Results indicated that motivation strategies had the highest positive correlations with GPA and persistence outcomes. For test scores, test taking strategies, anxiety, and selecting main ideas were the strongest positive correlates. Associations between LASSI subscales and outcomes were moderated by age, indicating lower correlations among students in postsecondary contexts compared to K-12 settings. Implications for research and practice regarding the role of strategic learning are discussed.This is the author accepted manuscript version of an article published in Educational Research Review.Curriculum and Instructio
Global Externalities, Local Policies, and Firm Selection
No full textFunding Information: Both authors are affiliated with the Helsinki GSE. We thank anonymous reviewers and the editor, as well as seminar participants at presentations in Athens (EAERE), Bergen, Gothenburg, Helsinki, Paris, Oslo, Torino (IEARE keynote), Toulouse (11th TSE Conference on Climate and Energy), and Zurich for valuable comments and discussion. We also thank Christoph Böhringer, Chang-Koo Chi, Baran Doda, Bård Harstad, Torfinn Harding, Daniel Hauser, Johannes Hörner, Yuanhao Li, Jussi Lintunen, Juan-Pablo Montero, Matias Pietola, Knut Einar Rosendahl, Julia Salmi, Thomas Sterner, Morten Sthre, Juuso Vålimåki, Ulrich Wagner, Po Yin Wong, and Andrey Zhukov for valuable comments and discussions. Lassi thanks support by Formas—a Swedish Research Council for Sustainable Development (Dnr: 2020-00174). Matti is grateful for funding from the Academy of Finland program New Energy, and from the Finnish Cultural Foundation. Publisher Copyright: © 2022 The Author(s) 2022. Published by Oxford University Press on behalf of European Economic Association.How to fight global problems with local tools? When only firms know what externality-producing activities can be relocated, policies shape the location distribution of firm types with different social values. We find that, because of this selection effect, the optimal local policies confront firms' mobility with elevated corrective externality prices, in contrast with the common remedies for the relocation risk. Our mechanism incentivizes also moving firms to limit the externality, and it influences strategically the distribution of moving firms that comply with policies elsewhere. The magnitude of these effects is illustrated by a quantification for the key sectors in the European Union emissions trading system.Peer reviewe
Ni–Fe–Co alloy – magnesia-iron-silicate slag equilibria and the behavior of minor elements Cu and P in nickel slag cleaning
No full textFunding Information: The study received financial support from the BATCircle (grant 4853/31/2018) by Business Finland. Lassi Klemettinen is grateful for the doctoral study grant provided by the Finnish Steel and Metal Producers' Fund and the funding provided by Aalto University School of Chemical Engineering. This study utilized the Academy of Finland's RawMatTERS Finland Infrastructure (RAMI) based at Aalto University, GTK and VTT in Espoo. Mia Tiljander at Geological Survey of Finland is greatly appreciated for conducting the EPMA analyses. Funding Information: The study received financial support from the BATCircle (grant 4853/31/2018 ) by Business Finland. Lassi Klemettinen is grateful for the doctoral study grant provided by the Finnish Steel and Metal Producers' Fund and the funding provided by Aalto University School of Chemical Engineering . This study utilized the Academy of Finland's RawMatTERS Finland Infrastructure (RAMI) based at Aalto University, GTK and VTT in Espoo. Mia Tiljander at Geological Survey of Finland is greatly appreciated for conducting the EPMA analyses. Publisher Copyright: © 2021 The Author(s)The increasing demand for metals and the tightening environmental restrictions on industries have led to a situation where improvements of new and existing process technologies for higher metal recoveries from primary and secondary resources are needed. This, in turn, requires a better understanding of process chemistry. The present study provides important fundamental information on the equilibrium reduction path and the formation of metal alloy in an electric furnace under nickel slag cleaning conditions, as well as the chemical properties of Ni, Co, Cu and P at these conditions. High-temperature equilibration experiments were conducted on magnesia-iron-silicate slags at silica saturation at 1400 ˚C (1637.15 K) and in the oxygen partial pressure range of 10−11–10−7 atm (1.01325 × 10−6–10−2 Pa). The samples were analyzed by electron microprobe (EPMA) for major and minor elements and laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) for trace element compositions. Initially the slag contained 2 wt% Ni and 1 wt% Cu, Co and P each, added as oxides, and at PO2 = 10−7 atm, these metals were only present in the slag with no metal alloy formed. At lower partial pressures, the alloy formed and its composition changed from 90wt-% Ni-rich to 50 wt-% Ni – 40 wt% Fe alloy as the PO2 decreased. Copper vaporized to a great extent at all conditions. The minor metals were shown to be present as NiO, PO2.5, CoO and CuO0.5 species in slag over the PO2 = 10−8–10−10 atm range.Peer reviewe
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