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| 1 | Electronic structure of the SrAl_2O_4:Eu^(2+) persistent luminescence material显示文摘The electronic structure of the strontium aluminate (SrAl2O4:Eu2+) materials was studied with a combined experimental and theoretical 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 va- lence and conduction bands as well as the band gap energy of the material together with the position of the Eu2+ 4f7 8S7/2 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 8S7/2 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. | Jorma Hls Taneli Laamanen Mika Lastusaari Janne Niittykoski Pavel Novák | 2009 | Journal of Rare Earths2009，27，4： | 9 |
| 2 | Synchrotron radiation investigations of the Sr_2MgSi_2O_7:Eu^(2+),R^(3+) persistent luminescence materials显示文摘The electronic and defect energy level structure of polycrystalline Sr2MgSi2O7:Eu2+,R3+ 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 fine 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 Sr2MgSi2O7:Eu2+,R3+ were assembled and their contributions discussed. | Tuomas Aitasalo Jukka Hassinen Jorma Hls Taneli Laamanen Mika Lastusaari Marja Malkamki Janne Niittykoski Pavel Novák | 2009 | Journal of Rare Earths2009，27，4： | 5 |
| 3 | Defect aggregates in the Sr_2MgSi_2O_7 persistent luminescence material显示文摘The crystal and electronic structure of the Eu2+ doped and defect containing Sr2MgSi2O7 persistent luminescence material were studied using the density functional theory(DFT) .The defects may act as energy storage or even luminescence quenching centres in these materials,however their role is very difficult to confirm experimentally.The probability of vacancy formation was studied using the total en-ergy of the defect containing host.Significant structural modifications in the environment of the isolated defects,especially the strontium va-cancy,as well as defect aggregates were found.The experimental band gap energy of Sr2MgSi2O7 was well reproduced by the calculations.The defect induced electron traps close to the host's conduction band were found to act as energy storage sites contributing to its efficient per-sistent luminescence.The interactions between the defects were found to modify both the Eu2+ 4f7 ground state energy as well as the trap structure.The effect of charge compensation induced by the rare earth co-doping on the defect structure and energy storage properties of the persistent luminescence materials was discussed. | Jorma Hls Taneli Laamanen Mika Lastusaari Pavel Novák | 2011 | Journal of Rare Earths2011，29，12： | 2 |
| 4 | SEM observations on stress corrosion cracking of commercially pure titanium in a topical fluoride solution显示文摘 | Mauno H O Kononen Eeva T Lavonius Jorma K Kivilahti | 1995 | Dent Mater1995，11，： | 1 |
| 5 | Increased type I collagen degradation correlates with disease severity in rheumatoid arthritis 显示文摘 | Markku H Leila R Jorma M | 1993 | Ann Rheum Dis1993，52，4： | 1 |
| 6 | Increased type I collagen deg- radation correlates with disease severity in rheumatoid arthritis 显示文摘 | Markku H Leila R Jorma M | 1993 | Ann Rheum Dis1993，52，： | 1 |
| 7 | SEM observations on stress corrosion cracking of commercially pure titanium in a topical fluoride solution 显示文摘 | MAUNO H KIINIINEN 0 LAVONIUS EEVA T KIVILAHTI JORMA K | 1995 | Dental Materials1995，11，4： | 1 |
| 8 | Increased type I collagen degradation correlates with disease severity in rheumatoid arthritis 显示文摘 | Markku H Leila R Jorma M | 1993 | Ann Rheum Dis1993，52，： | 1 |
| 9 | Low vs high radioiodine activity to ablate the thyroid after thyroidectomy for cancer: a randomized study显示文摘 | Hanna OM Jorma H Leila V | 2008 | PIoS ONE2008，3，4： | 1 |
| 10 | Fecal Microbiota Composition Differs Between Children With [Beta]-Cell Autoimmunity and Those Without显示文摘 | de Goffau Marcus C Luopaj?rvi Kristiina Knip Mikael Ilonen Jorma Ruohtula Terhi H?rk?nen Taina Orivuori Laura Hakala Saara Welling Gjalt W Harmsen Hermie J Vaarala Outi | 2013 | Diabetes2013，，4： | 1 |
| 11 | Effect of Mg 2+ and Ti IV doping on the luminescence of Y 2 O 2 S:Eu 3+显示文摘 | Jorma H?ls? Taneli Laamanen Mika Lastusaari Marja Malkam?ki Janne Niittykoski Eugeniusz Zych | 2009 | Optical Materials2009，，12： | 1 |
| 12 | Modified integrator for voltage model flux estimation of induction motors 显示文摘 | MARKO H JORMA L | 2003 | IEEE Transactions on In- dustrial Electronics2003，50，4： | 1 |
| 13 | Changes in male reproductive health and effects of endocrine disruptor in Scandinavian countries 显示文摘 | Jorma T Anne M H Markku A | 2002 | Cad Satide P6blica Riode Janeiro2002，18，2： | 1 |
| 14 | Properties of aluminum oxide thin films deposited by reactive magnetron sputtering 显示文摘 | Kari K Jorma H Pierre J | 1999 | Thin Solid Films1999，339，12： | 1 |
| 15 | Increased type I collagen degradation correlates with disease severity in rheumatoid arthritis显示文摘 | Markku H Leila R Jorma M | 1993 | Ann Rheum Dis1993，52，12： | 1 |
| 16 | Persistent luminescence of Eu^2+ doped alkaline earth aluminates, MAl2O4 : Eu^2+ 显示文摘 | Jorma H Hogne J Mika L | 2001 | J Alloys and Compounds2001，，： | 1 |
| 17 | Mechanisms of persistent luminescence in Eu^2+ , RE^3+ doped alkaline earth aluminates显示文摘 | Tuomas A Jorma H Hogne J | 2001 | J Lumin2001，9495，： | 1 |
| 18 | Up-conversion luminescence properties of Y2O2S:Yb3+,Er3+ nanophosphors 显示文摘 | IKO H JORMA H JOUKO K | 2009 | Optical Mater2009，，31： | 1 |
| 19 | Chemical composition and size of particles in emissions of a coal-fired power plant with flue gas desulfurization显示文摘 | Karri Saarnio Anna Frey Jarkko V. Niemi Hilkka Timonen Topi R?nkk? Panu Karjalainen Mika Vestenius Kimmo Teinil? Liisa Pirjola Ville Niemel? Jorma Keskinen Anna H?yrinen Risto Hillamo | 2014 | Journal of Aerosol Science2014，，： | 1 |
| 20 | Effect of impact exercise on bone mineral density in elderly women with low BMD: A population-based randomized controlled 30- month intervention显示文摘 | KORPELAINEN R SIRKKA K K JORMA H | 2006 | Osteoporos Int2006，17，： | 1 |
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