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Electronic structure of the SrAl_2O_4:Eu^(2+) persistent luminescence material

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Journal of Rare Earths 2009年第4期27卷 550-554页

作者： jorma hls Taneli Laamanen Mika Lastusaari Janne Niittykoski Pavel Novák Department of Chemistry University of Turku FI-20014 Turku Finland Turku University Centre for Materials and Surface (MatSurf) Turku Finland Graduate School of Materials Research (GSMR) Turku Finland Institute of Physics Academy of Sciences of the Czech Republic CZ-16253 Prague 6 Czech Republic

The electronic structure of the strontium aluminate （SrAl2O4：Eu^2＋） materials was studied with a combined experimental and theo- retical approach. The UV-VUV synchrotron radiation was applied in the experimental study while the electronic structure of the non-optimized and optimized crystal structure were investigated theoretically by using the density functional theory. The structure of the valence and conduction bands as well as the band gap energy of the material together with the position of the Eu2＋ 4f7 85712 ground state were calculated. The calculated band gap energy （6.4 eV） agreed well with the experimental value of 6.6 eV. The valence band consisted mainly of oxygen states whereas the bottom of the conduction band of strontium states. In agreement with the experimental results, the calculated 4f7 8S7r2 ground state of Eu2＋ lies in the energy gap of the host. The position of the 4f7 ground state depended on the Coulomb repulsion strength. The position of the 4f7 ground state with respect to the valence and conduction bands was discussed using theoretical and experimental evidence available.

关键词： strontium aluminate persistent luminescence electronic structure DFT calculation rare earths

Synchrotron radiation investigations of the Sr_2MgSi_2O_7:Eu^(2+),R^(3+) persistent luminescence materials

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Journal of Rare Earths 2009年第4期27卷 529-538页

作者： Tuomas Aitasalo Jukka hassinen jorma hls Taneli Laamanen Mika Lastusaari Marja Malkamki Janne Niittykoski Pavel Novák Department of Chemistry University of Turku FI-20014 Turku Finland Turku University Centre for Materials and Surfaces (MatSurf) Turku Finland Graduate School of Materials Research (GSMR) Turku Finland Institute of Physics Academy of Sciences of the Czech Republic CZ-16253 Prague 6 Czech Republic

The electronic and defect energy level structure of polyerystalline Sr2MgSi2OT：Eu^2＋,R^3＋ persistent luminescence materials were studied with thermoluminescence and different synchrotron radiation spectroscopies （UV-VUV emission and excitation, X-ray absorption near-edge spectroscopy （XANES） and extended X-ray absorption f＇me structure （EXAFS））. Special attention was paid on the effect of the R3＋ co-dopants on the persistent luminescence properties of the materials. Theoretical calculations using the density functional theory （DFT） were carried out simultaneously with the experimental work. The experimental band gap energy （Eg） value of ca. 7.1 eV agreed very well with the DFT value of 6.7 eV. The variation of the Eg value was attempted to relate with the trap structure as well as with the different properties of the R3＋ co-dopants. The trap level energy distribution depended strongly on the R3＋ co-dopant except for the shallowest trap energy above the room temperature remaining practically the same, however. The different processes in the mechanism of persistent luminescence from Sr2MgSi2OT：Eu^2＋,R^3＋ were assembled and their contributions discussed.

关键词： strontium magnesium disilicate europium persistent luminescence synchrotron radiation thermoluminescence mechanism rare earths

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Basics of estimation

Frontiers of Electrical and Electronic Engineering in China 2010年第3期5卷 274-280页

作者： jorma RISSANEN helsinki Institute for Information Technology Tampere University of TechnologyTampere 33720Finland

This paper outlines a theory of estimation,where optimality is defined for all sizes of data—not only *** one principle is needed to cover estimation of both real-valued parameters and their *** achieve this we have to abandon the traditional assumption that the observed data have been generated by a“true”distribution,and that the objective of estimation is to recover this from the ***,the objective in this theory is to fit‘models’as distributions to the data in order to find the regular statistical *** performance of the fitted models is measured by the probability they assign to the data:a large probability means a good fit and a small probability a bad ***,the negative logarithm of the probability should be minimized,which has the interpretation of code *** are three equivalent characterizations of optimal estimators,the first defined by estimation capacity,the second to satisfy necessary conditions for optimality for all data,and the third by the complete Minimum Description Length(MDL)principle.

关键词： models optimal estimation estimation capacity complete Minimum Description Length(MDL)principle

Nitridation of Ni-based alloys:thermodynamics,kinetics,and deformation phenomena accompanying internal precipitation

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Rare Metals 2006年第5期25卷 501-511页

作者： Alexander A.Kodentsov jorma K.Kivilahti Frans J.J.van Loo Laboratory of Materials and Interface Chemistry Eindhoven University of TechnologyP.O.Box 5135600 MBEindhovenThe Netherlands Laboratory of Electronics Production Technology Helsinki University of TechnologyFIN-02150 EspooFinland

When a moderately stable phase is precipitated out during an intemal reaction, the behaviour of the penetrating atoms within the diffusion zone can be interpreted based on thermodynamic considerations. Evidence for “up-hill” diffusion of the penetrating species through the matrix towards the precipitation front during the intemal nitridation of Ni-Cr alloys at 1125℃ and 6000 bar of N2-pressure was predicted. Such behaviour of nitrogen is opposite to the boundary conditions in Wagner＇s description of internal reactions. A volume change associated with the precipitation reaction resulted in a stress gradient between the alloys surface and the intemal nitridation front. Stress relief occurred mainly by transport of nickel to the gas/metal interface. Pipe diffusion-controlled creep is the dominant stress accommodation mechanism during nitriding of dilute Ni-Cr alloys at 700℃ under a flowing Nh3 ＋ h2 gas mixture.

关键词： nitridation nickel alloys thermodynamics diffusion internal precipitation

Finland is following the trend--sperm quality in Finnish men

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Asian Journal of Andrology 2013年第2期15卷 162-164,I0004页

作者： helena E Virtanen Sergey Sadov Matti Vierula jorma Toppari Departments of Physiology and Paediatrics University of Turku Turku FI-20520 Finland

Finnish men have had a reputation for good semen quality. This was based on semen studies comparing Finnish men with other Europeans. however, those studies also showed that sperm concentrations of young men from the general population were only two-thirds of those of fertile men. Longitudinal follow-up of semen quality in young Finnish men showed a sig- nificant decline during 1998-2006, suggesting that Finland is following the global trend of impaired male reproductive health.

关键词： NORDIC-BALTIC AREA SEMEN QUALITY REGIONAL DIFFERENCES POPULATION FERTILITY COUNTS

Edible films based on milk proteins release effectively active immunoglobulins

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Food Quality and Safety 2019年第1期3卷 23-34页

作者： Pirjo Rantamäki Vuokko Loimaranta Erkki Vasara Jari Latva-Koivisto hannu Korhonen jorma Tenovuo Pertti Marnila Natural Resources Institute Finland FI-31600 JokioinenFinland Institute of Dentistry University of TurkuFI-20014 Turun yliopistoFinland

Objectives:The goal of this study was to develop novel compositions of edible protein coatings based on immunoglobulin(Ig)fraction from bovine *** coatings can be used to protect foods against microbial,chemical,and physical *** developed novel compositions of edible protein coatings based on immunoglobulin(Ig)fraction from bovine milk.A lot of Ig could be obtained from under-utilized side streams of dairy *** the best of our knowledge,such use of the Ig fraction has not been published *** and Methods:Bovine colostral Ig’s were incorporated in edible films based on various milk proteins and investigated the characteristics of the films including solubility of Ig’s and nisin and on technological properties of ***’s specific to cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus were produced to colostrums by hyperimmunizing cows before ***:The milk Ig rich fraction suited well as a component of milk protein *** Ig’s dissolved from the films very ***,commoly used for food protection,was used as a model of antimicrobial *** was released biologically active from bothβ-lactoglobulin(β-lg)andβ-lg/Ig *** exerted its bactericidal effect at clearly lower concentrations in theβ-lg/Ig films when compared withβ-lg *** also retained its activity better in film containing Ig-enriched *** Ig-enriched whey into films enhanced adhesion and tensile strength of the *** Ig-enriched whey also affected strongly on the appearance of films based on commercial whey protein concentrate in a dose-dependent way by making the films more smooth,transparent,and clear which are all favoured properties in most food and pharmaceutical ***:Biologically active Ig’s can be successfully incorporated in and released from milk protein based edible *** content of Igs in films affected considerably technological properties of these ***

关键词： edible films immunoglobulins whey proteins β-lactoglobulin caseinates nisin dental caries

Improving the law on the prevention and control of occupational diseases in China: an employer-supporting management perspective

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Global health Journal 2020年第2期4卷 33-41页

作者： Min Zhang jorma Rantanen School of Public health Chinese Academy of Medical Sciences and Peking Union Medical College9 Dongdan San TiaoBeijing 100730China Department of Public health/Occupational health University of HelsinkiP.O.BOX 20(Tukholmankatu 8 B)FIN-00014 HelsinkiFinland

A healthy workforce is fundamental for China to pursue its healthy China 2030 strategy and the UN Sustainable Development *** Law of the People’s Republic of China on the Prevention and Control of Occupational Diseases(the Chinese OD Law),which has been amended four times since its adoption in 2002,is the core and cornerstone of the entire regulatory system for occupational *** addition to discussing the new institutional reforms,which are relevant to China’s regulatory system for occupational diseases(ODs)because of their marked impact on healthcare system reform,we present further evidence,mainly drawn from desk and field *** study focuses on the barriers that employers face in complying with the Chinese OD Law and explores the optimized employer-initiated management system,which requires further amendments to the Chinese OD Law,as the State Council of China has prioritized this issue as a top *** first summarize the key characteristics of the Chinese OD Law and illustrate employers’essential obligations,and then analyze the critical challenges that employers face regarding OD prevention and *** demonstrate good practices and experiences in China,and,finally,propose recommendations for further amendments to the Chinese OD Law in the near *** recommendations can be achieved only through integrating the healthcare system reform with mechanism innovation.

关键词： Occupational diseases Occupational health Law Employer China

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BelBaie V夹网成形器

中华纸业 2004年第12期25卷 27-29页

作者： jorma Vanttinen

BelBaieV继承了BeloitBelBaieⅡ和BelBaieⅢ型夹网成形器成纸匀度良好的特征,可提高脱水能力,减少两面差,并提高纸机潜在的工作车速,从而提高纸机的生产能力。本文介绍了BelBaieV成形器的结构特征、优点、使用效果等。

关键词：夹网成形器纸机两面差匀度结构特征脱水车速生产能力水能优点

Determinants of international joint venture performance measurement： A theoretical framework

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Journal of Modern Accounting and Auditing 2010年第11期6卷 11-24页

作者： Nguyen huu Le Larimo jorma Department of Management and Organization Hanken School of Economics Vaasa 65101 Finland Faculty of Business Studies University of Vaasa Vaasa 65101 Finland

International joint ventures （IJVs） have increasingly their role in business world and also in research field of international business. There have been a lot of studies related to determinant factors of IJV performance. however, there are very few studies focusing on the measurement of I Jr performance. Especially, researchers have ignored how foreign parent firms really choose their measures in the evaluation of their IJV performance. This research investigates determinant factors of performance measures of 1JVs. Determinant factors of IJV performance measures include motives for establishment, establishment mode, location of IJVs, distribution of ownership in IJVs, cultural background of parent firms, and trust between partners, IJV life stages, parent firms＇ international experience, and relatedness of the IJVs to their parents. Performance measures are divided into financial measures and non-financial measures. The paper shows how different determinant factors are expected to lead foreign parent firms preferring one kind of measure over the other.

关键词： international joint ventures performance measurement non-financial measures financial measures