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Ce-doped Lu 2 Si 2 O 7 scintillator contains radioactive isotope 176 Lu which causes an unwanted intrinsic background signal. The development of scintillators with reduced Lu concentration were required in some applications. In this study, we developed the Gd admixed lutetium pyrosilicate, where the average ion radius at the rare earth site was similar to the Tm 3+ ion radius, for which the RE 2 Si 2 O 7 (RE=Tm, Yb, Lu) crystal structure is stable from room temperature to melting point. We have grown (Ce x Lu 1−x−y Gd y ) 2 Si 2 O 7 (x=0.01, y=0.00, 0.05, 0.10) single crystals. Their crystal systems were monoclinic with a space group C 2/ m . The absorption spectra revealed the energy transitions in Ce and Gd ions might be occurred. The light output was degraded and decay time was accelerated comparing the Gd 5% admixed sample with the Gd 10% one. [ABSTRACT FROM AUTHOR]

Mg co-doped Ce1%:Gd 3 Ga x Al 5−x O 12 (Ce:GAGG) crystals (x=2.4, 2.7, 3.0) were successfully grown by the Czochralski (Cz) method. Effect of Mg co-doping on the scintillation properties of Ce:GAGG was examined. This study covers measurements of solidification fraction and scintillation properties such as light yield, energy resolution and non-proportionality for each crystal. Pulse-height spectra of various gamma and X-ray sources with energies ranged from 30 keV to 662 keV were measured. Regardless of the presence/absence of Mg dopant, the non-proportionality curves with lower content of gallium in the crystal structure tend to improve. Mg co-doped Ce:GAGG samples did not show a significant difference as compared with non co-doped Ce:GAGG. Mg co-doped crystals with x=2.4 and 2.7 showed the promising scintillation properties of faster decay time and higher energy resolution than those with x=3.0. [ABSTRACT FROM AUTHOR]

The relationship among lattice constant a , Al content, and acoustic properties were experimentally examined using a plate specimen perpendicular to Y -axis prepared from Ca 3 Ta(Ga 0.75 Al 0.25 ) 3 Si 2 O 14 [CTGAS(0.25)] single crystal grown by Czochralski method. As the acoustic properties, leaky surface acoustic wave (LSAW) velocities with different propagation directions, X - and Z -propagations, and longitudinal wave velocity propagating along Y -axis direction were measured by the line-focus-beam/plane-wave ultrasonic-material-characterization (LFB/PW-UMC) system. The measured results of LSAW velocity distributions revealed inhomogeneity in radial direction of the crystal ingot exhibiting lower velocity area at the center of the ingot. In addition, the distributions of lattice constant a and chemical composition (especially Al content) were measured along the radial direction. Abnormal changes suggesting existence of residual stresses concentrated on the central part of the crystal ingot other than the effect of chemical composition change were detected from the relationships among the measured parameters. [ABSTRACT FROM AUTHOR]

Ce-doped (Gd, La) 2 Si 2 O 7 scintillators have fast decay time and keep high light output even at high temperature (∼150°C). To improve the scintillation properties such as light output and decay time, Ce-doped (Gd, La) 2 Si 2 O 7 scintillators codoped with the divalent ions (e.g. Mg 2+ , Ca 2+ ) have been studied. In this study, we focused on the other divalent ions (Sr 2+ and Ba 2+ ), and investigated their effect on the scintillation properties and temperature dependence of light output. The absorption due to Ce 4+ was not observed for Sr or Ba codoping. The light outputs were degraded by Sr 2+ or Ba 2+ codoping, while the decay times at room temperature were not changed for the samples codoped with divalent ions. On the other hand, the temperature dependence of light output for Ba-codoped sample was improved, and the light output value at 175°C was 36,000 photons/MeV, which was 93% of that at 25°C. [ABSTRACT FROM AUTHOR]

Eu doped LiSrI 3 /LiI eutectics were grown by the Bridgman method in a quartz ample with 4 mm inner diameter. and their directionally solidified eutectic system has been investigated. Growth rate was 0.3 mm/min. The eutectic showed well aligned eutectic structure and optically transparent. Grown Eu doped LiSrI3/LiI eutectic shows 400 nm emission ascribed to Eu 2+ 4f-5d transition under X-ray excitation. The light yield was around 26,000 photon/MeV for 662 keV gamma-ray and 35,000 photons for 5.5 MeV alpha-ray. [ABSTRACT FROM AUTHOR]

(Ce 0.01 Gd 0.59 La 0.40 ) 2 Si 2 O 7 single crystal (La40% sample) was grown by the micro-pulling-down method to study its scintillation properties and their temperature dependence. In addition, we investigated the relation between these properties and La concentration comparing the crystal with (Ce 0.01 Gd 0.90 La 0.09 ) 2 Si 2 O 7 (La9% sample). As results, the light output of the La40% sample at 25°C was similar to that of the La9% sample. On the other hand, the decay time of the La40% sample was slower than that of the La9% sample at 25°C. The light output of La40% sample had a small decrease rate at high temperature when compared with that of La9% sample. [ABSTRACT FROM AUTHOR]

The In-doped LiCaAlF 6 [In:LiCAF] single crystals were grown by the micro-pulling-down (μ-PD) method, and the phases, chemical compositions, transmittance and radioluminescence spectra were investigated. All the grown crystals showed high transparency and single phase of LiCAF without visible cracks and inclusions except for the end part of In2%:LiCAF crystal which included the impurity phase. In the radioluminescence spectra of the In:LiCAF crystals under X-ray irradiation, the emission peak around 750 nm was revealed. [ABSTRACT FROM AUTHOR]

Tb-doped LiGdF 4 -LiF eutectics were grown at various growth rate and their directionally solidified eutectic (DSE) system has been investigated. Well aligned fiber like eutectic structure with around 1.7 μm in diameter and 1200 μm in maximum length was obtained the growth speed of 0.15 mm/min. The sample showed optical transparency like bundle optical fibers and around 40% of transmittance at 1.5 mm thick was achieved in 380–630 nm range. The expected 380–630 nm emission exited by UV and α-ray, and 270–330 nm excitation of Tb 3+ 8 S - 6 P transition have been observed. The weak emission of Gd 3+ 4f-4f transition at 310 nm was also observed under alpha-ray excitation. The Observed excitation bands peaking at around 275 nm and 310 nm correspond respectively to the 8 S 7/2 - 6 I 7/2 and 8 S 7/2 - 6 P J absorption bands of Gd 3+ . [ABSTRACT FROM AUTHOR]

(Ce x Yb 1−x ) 2 Si 2 O 7 (x = 0.00, 0.01) single crystals were grown by the micro-pulling-down method to test the possibility of its application as infra-red scintillator for medical imaging. Powder X-ray diffraction analysis indicated that the crystals were single-phase materials. The radioluminescence spectra of the crystals demonstrated presence of two near infra-red emission peaks (at 1010 and 1030 nm). The emission peaks at 420 and 580 nm ascribed to defects were also observed in the crystals. The human body has maximum transmission in wavelength range from 650 to 1200 nm. Therefore, Yb 2 Si 2 O 7 is expected to be used as efficient infra-red scintillator for medical applications. [ABSTRACT FROM AUTHOR]

The ns 2 -type metal elements (Pb and Sn) doped LiCaAlF 6 single crystals were grown by a micro-pulling-down (μ-PD) method. Pb doped LiCaAlF 6 [Pb:LiCAF] crystals showed high transparency and single phase of the LiCAF structure. However, we could not obtain Sn:LiCAF crystals due to the evaporation of SnF 2 during the crystal growth. There was an absorption peak around 193 nm in the transmittance spectrum of Pb:LiCAF crystal. In the radioluminescence spectrum of the Pb:LiCAF crystal under X-ray irradiation, two emission peaks around 200 and 830 nm were observed. [ABSTRACT FROM AUTHOR]

1300 or 1400 °C pre–sintered Al/Ce/Mg:SrHfO 3 and Al/Ce:SrHfO 3 ceramics were prepared by the Spark Plasma Sintering (SPS) in order to search for a new scintillation material with a high–effective atomic number(Z eff ) and good light output. The SrHfO 3 has a high Z eff of 60, and high gamma–ray detection efficiency is expected. Meanwhile it has a high melting point of over 2500 °C, and single crystal is hard to be grown. On the other hand, high melting materials can be prepared as ceramics, and the SPS method is a simple process to fabricate the ceramics within a few hours. Thus, we prepared the samples using the SPS method, and their optical and scintillation properties were investigated. We found that Al/Ce/Mg:SrHfO 3 and Al/Ce:SrHfO 3 ceramics had an emission wavelength at around 400 nm originating from 5d–4f transition of Ce 3+ . Moreover, Al/Ce/Mg:SrHfO 3 pre-sintered at a temperature of 1400 °C had a light output of approximately 5,000 ph/MeV. In this paper, the light output of Mg-co-doped samples was improved compared with the Mg-free ones. The light output also depends on the pre-sintering temperature. [ABSTRACT FROM AUTHOR]

Eu doped BaCl 2 /LiF eutectics were grown by the micro-pulling down method and their directionally solidified eutectic (DSE) system has been investigated. The grown eutectic showed main phases of cubic LiF and orthorhombic BaCl 2 . In these eutectics, the 399 nm emission of Eu 2+ 4f5d was obtained. It shows the intrinsic decay time of about 410 ns. The light yield of the 1-mm-thick eutectic showed 7000 ph/5.5 MeV alpha-ray. [ABSTRACT FROM AUTHOR]

Highlights: [•] Yb-doped Gd3Al2Ga3O12 (Yb:GAGG) crystal was grown by a micro-pulling down method. [•] Crystal structure and average chemical composition of Yb:GAGG was examined. [•] Yb:GAGG crystal was highly transparent in infra-red region from 650 to 1200nm. [•] Yb:GAGG showed infra-red scintillation peaks at 1030nm under X-ray excitation. [ABSTRACT FROM AUTHOR]

Abstract: We have investigated the optical properties of 1mol% Nd-doped SrBr2 crystal grown by the Bridgman technique for an X-ray scintillator application. We succeeded in obtaining a transparent crystal, whose X-ray diffraction was measured under dry condition because of its hygroscopic nature. Roughly, we estimated that 90% of this crystal dissolved within 300min. under 25°C and 65–70% humidity. Under excitation by 270 and 400nm photons several emission peaks originating from 4F3/2 or 4G i1→4I i2 (i1=5/2 and 7/2 and i2=13/2, 11/2, and 9/2) transitions of Nd3+ were observed. 1mol% Nd:SrBr2 had a maximum quantum yield of approximately 45%. Additional emission peaks were observed under X-ray excitation. [Copyright &y& Elsevier]

• Mg2+ codoping effect on the atoms segregation in GAGG:Ce single crystal studied. • The formation of defects in Mg2+ and Ce3+ codoped GAGG crystals discussed. • The luminescence quenching mechanism in Mg2+ codoped proposed. • The charge compensation mechanism discussed. • Mg2+ codoping influence on the scintillation and luminescence properties investigated. The undoped, Mg2+ doped, Ce3+ doped as well as Mg2+:Ce3+ codoped Gd 3 Al 2 Ga 3 O 12 crystals were grown from the melt by the micro-pulling down method. Ce3+ and Mg2+ ions were codoped in a wide concentration range. A study of Mg2+ ion concentration effect on the luminescence and scintillation properties as well as segregation of atoms and defects creation processes were carried out. Mg2+ doping in Gd 3 Al 2 Ga 3 O 12 led to the creation of O O • defects localized next to Mg2+ sites due to charge imbalance compensation. Consequently, neutral (Mg Ga/Al/Gd O O) x defects were formed. In Ce3+ doped crystals, Mg2+ codoping changed the valence state from Ce3+ to Ce4+ to maintain charge neutrality. Hence, additional neutral (Ce Gd • -Mg Ga/Al/Gd ′) x and (Ce Gd -Mg Ga/Al/Gd O O) x defects appeared. Moreover, Mg2+ induced charge imbalance in GAGG crystal might also be compensated by the formation of oxygen vacancies (V O •• ). The Mg2+ ions imposed defects deteriorated the segregation of atoms. Accordingly the radial inhomogeneity of the crystals was diminished. The presence of stable Ce4+ and defects imposed by Mg2+ ions codoping were proved by absorption, photoluminescence, and scintillation decay time analysis. Hence, Mg2+ codoping resulted in quenching of the Ce3+ luminescence, acceleration of scintillation response, reduction of light yield, and thermally stimulated luminescence. The mechanism explaining a strong luminescence quenching with increasing Mg2+ ions concentration was proposed. [ABSTRACT FROM AUTHOR]

• Ce doped LaCl 3 /AECl 2 (AE = Mg, Ca, Sr) eutectics were grown by BS method. • In case of AE = Mg, Ca, eutectic with PSSFs structures were observed. • The Ce:LaCl 3 /CaCl 2 eutectic showed Ce3+ 4f-5d emission at 345 nm. • The light output of Ce:LaCl 3 /CaCl 2 under 137Cs was 9000 photons/MeV. • The scintillation decay time under 137Cs was 26.8 ns (26%) and 282 ns (74%). Ce-doped LaCl 3 /AECl 2 (AE = Mg, Ca, Sr) system eutectics were explored. Ce-doped LaCl 3 / AECl 2 (AE = Mg, Ca, Sr) eutectics were grown using the Bridgman–Stockbarger method in quartz ampoules. In the case of AE = Mg, Ca, eutectics with submicron-diameter phase-separated scintillator fibers (PSSFs) structure were observed. In the case of AE = Sr sample, a solid solution of La 0.708 Sr 0.292 Cl 2.708 was observed. The plate sample from the grown eutectics has some transparency. The grown eutectic structure showed a mixture of rods and plates shape. This mixed structure was aligned with a length of around 100–400 μm. The Ce:LaCl 3 /CaCl 2 eutectic showed 345 nm emission ascribed to Ce3+ 4f-5d transition under X-ray excitation. The Ce:LaCl 3 /CaCl 2 sample resulted in the highest light output of 9,000 photon/MeV, which is comparable to the previously reported eutectic scintillator Ce:GdAlO 3 /α-Al 2 O 3 , 9500 photon/MeV. Scintillation decay time of the Ce:LaCl 3 /CaCl 2 sample under 662 keV gamma-ray excitation was 26.8 ns (26%) and 282 ns (74%). [ABSTRACT FROM AUTHOR]

• La 2 Hf 2 O 7 crystals (m.p.: 2418 °C) were grown by the µ-PD method using a W crucible. • The La 2 Hf 2 O 7 grown at a rate of 2.00 mm/min had some cracks. • The La 2 Hf 2 O 7 grown at a rate of 0.07 mm/min was transparent without any cracks. • The LHO[0.07 mm/min] had a transmittance of over 70% in the range of 450–800 nm. • The XRC of the LHO[0.07 mm/min] showed a sharp peak with a FWHM of 138 arcsec. La 2 Hf 2 O 7 crystals with a melting point of ∼2418 °C were grown by the micro-pulling-down method using a W crucible and deoxygenated ZrO 2 insulators. A La 2 Hf 2 O 7 crystal grown at a rate of 0.07 mm/min (LHO[0.07 mm/min]) showed a high transparency without any visible cracks and inclusions, while a La 2 Hf 2 O 7 crystal grown at a rate of 2.00 mm/min had some cracks. The LHO[0.07 mm/min] crystal had a transmittance of over 70% in the wavelength range of 450–800 nm. The X-ray rocking curve of the LHO[0.07 mm/min] crystal showed a symmetric sharp peak with a full width at half maximum of 138 arcsec. The Laue image revealed that the grown crystals were single crystals. [ABSTRACT FROM AUTHOR]

In this study, Ce:6LiBr/LaBr 3 eutectic with a high Li concentration was developed as a novel thermal neutron scintillator. Ce served as an activator for the LaBr 3 phase, and Ce:6LiBr/LaBr 3 eutectics were grown via the vertical Bridgman method in quartz ampoules (inner diameter = 4 mm). In the eutectic, the 6LiBr phase worked as the neutron capture phase by the 6Li (n, a) 3H reaction, and Ce:LaBr 3 worked as the scintillator phase. The Ce:6LiBr/LaBr 3 eutectic exhibited a lamellar eutectic structure and optical transparency, as well as 350 and 380 nm emission due to Ce 3 + 5d-4f transition. The light yield under neutrons excitation was estimated to be 74000 photons/neutron. The scintillation decay time was 18.7 ns. • Optically semitransparent Ce-doped 6LiBr/LaBr 3 eutectic was grown. • The vertical Bridgman–Stockbarger (VB) method enables unidirectional solidification to grow the directionally solidified eutectic (DSE). • Ce 3 + emission peaks at 350 and 380 nm were observed in the LaBr 3 phase. • Scintillation decay time under 252Cf neutron excitation was 18.7 ns. • The light yield under 252Cf neutron excitation was around 74000 photon/neutron. [ABSTRACT FROM AUTHOR]

Abstract: Capability of thermal neutron detection was examined for LiCaAlF6 (LiCAF) scintillators doped with 3d-transition metal ions. Their radioluminescence spectra were measured with an 241-Am source to simulate 6Li(n, α)3H reaction. The sufficiently intense radioluminescence was observed for the Mn, Co and Cu dopants, while only a weak one was observed for Ti, V, Fe and Ni. A Mn doped LiCAF crystal, which showed the highest radioluminescence intensity, was coupled with a Si avalanche photodiode for the examination of its neutron response. It was confirmed that the average current of the photodiode clearly increased under excitation with 13.5 meV neutron flux. [Copyright &y& Elsevier]

Abstract: 1, 3, and 6mol% Nd3+ doped (YGd2)(Sc2Al2Ga)O12 transparent ceramic garnets were fabricated by the sintering to investigate their optical and scintillation properties. They were all visibly purplish and exhibited 80% transparency in wavelength longer than 300nm with several absorption bands due to Nd3+ and Gd3+ 4f–4f transitions. In photo- and radio-luminescence spectra, they showed intense emission peaks at 383 and 416nm. Photoluminescence decay time of the former resulted ∼500μs and those of the latter 400 and 900ns, respectively. Scintillation light yield was examined by using 241Am 5.5MeV α-ray and the light yield resulted ∼200photons/5.5MeV α in Nd 1mol% doped sample. [Copyright &y& Elsevier]

Abstract: The Nd-doped Lu3Al5O12 (Nd:LuAG) single crystal was grown by the Czochralski (CZ) method. In XRC profiles, the full-width at half-maximum (FWHM) value was 58arcsec, which was much higher than that of the μ-PD (194arcsec). In photo and radio-luminescence spectra, the CZ grown sample showed strong emission peaks attributed to Nd3+ 4f–4f transitions in visible wavelengths longer than 400nm. The Nd:LuAG grown with the CZ method showed light yield of 7900 photons/MeV, which is comparable with the standard BGO and energy resolution of 14% under 137Cs γ-ray excitation. [Copyright &y& Elsevier]

Abstract: Er- and Tm-doped LiCaAlF6 (LiCAF) single crystals were grown by the micro-pulling-down (μ-PD) method. The crystals were transparent, 2.0mm in diameter and 30–40mm in length. Neither visible inclusions nor cracks were observed. Photoluminescence spectra of Er- and Tm-doped LiCAF were measured. Broad band emission due to the Tm3+ and Er3+ 5d–4f transitions dominated the spectrum at 163.5 and 165 nm respectively. These emissions had shortest wavelength among the fluoride crystal hosts ever reported at room temperature experiments. The vacuum ultraviolet (VUV) luminescent crystals are attractive as scintillators for radiation detectors, which employ photosensitive gases (such as TMAE or TEA) or photocathodes (such as CsI) sensitive mostly to VUV photons. [Copyright &y& Elsevier]

• A novel ternary Tb:BaCl 2 /NaCl/KCl eutectic scintillator is reported. • Directionally solidified eutectic was grown by the VB method. • Columnar BaCl 2 fibres with a length of 300 μm were obtained at a growth rate of 0.01 mm/min. • The expected Tb3+ emission was observed only in the BaCl 2 phase. • The decay times of the eutectic were 0.49 ms (7.5%) and 6.64 ms (92.5%) In this study, Tb:BaCl 2 and NaCl/KCl ternary eutectics were grown using quartz ampoules via the vertical Bridgman–Stockbarger method. Each crystal phase had a polygonal columnar shape with a length of 300 µm along the growth direction. The Tb:BaCl 2 scintillator phase grew in the columnar phase. The BaCl 2 scintillator phase is expected to make optical waveguides of the scintillation light. The expected Tb3+ emission peak was observed at approximately 360–630 nm under X-ray irradiation. This emission is mainly attributed to the Tb3+5D 4 →7F 6, 7F 6 , 7F 5 , 7F 4 , and 7F 3 transitions and BaCl 2 host emission transition. The photoluminescence decay times of the Tb:BaCl 2 /NaCl/KCl eutectics was 0.49 ms (7.5%) and 6.64 ms (92.5%). [ABSTRACT FROM AUTHOR]

• La 2 Zr 2 O 7 crystals were grown by micro-pulling-down method using Mo & W crucibles. • Grown crystals under Ar + 3%H 2 were composed of La 2 Zr 2 O 7 phase including Mo and W. • A grown crystal under Ar using W crucible & deoxygenated insulator was La 2 Zr 2 O 7. • The La 2 Zr 2 O 7 crystal indicated a transmittance exceeding 70% after post-annealing. La 2 Zr 2 O 7 crystals with a melting point of 2283 °C are grown via the micro-pulling-down (μ-PD) method using Mo and W crucibles to expand the possibility of material research of functional single crystals with high melting points by the μ-PD method. La 2 Zr 2 O 7 crystals grown using Mo and W crucibles under an Ar + 3% H 2 atmosphere are composed of a La 2 Zr 2 O 7 main phase, which includes Mo and W. However, a La 2 Zr 2 O 7 crystal without W can be grown under an Ar atmosphere using the μ-PD method using a W crucible and deoxygenated ZrO 2 insulators. After post-annealing in air at 1000 °C, the La 2 Zr 2 O 7 crystal without W becomes colorless and transparent, indicating a transmittance exceeding 70% in wavelengths ranging from 450 to 800 nm. [ABSTRACT FROM AUTHOR]

• A novel ternary CsI/KI/KCl eutectic scintillator is reported. • Directionally solidified eutectic was grown using the Bridgman–Stockbarger method. • The expected Tl+ emission peak near 486 nm was observed in the CsI phase. • The decay time of the eutectic was 313 ns. • The light output of the eutectic was approximately 22,000 photons/MeV. In this study, Tl:CsI/KI/KCl eutectic scintillators were grown using the Bridgman–Stockbarger method by unidirectional solidification. The eutectic phases were uniformly distributed in the transverse direction and were slightly aligned along the growth direction. The Tl:CsI scintillator phase was grown as a matrix, which was then used for creating optical waveguides of the scintillation light. The expected Tl+ emission peak was observed at 486 nm under X-ray excitation and cathodoluminescence; this was attributed to the self-trapped exciton perturbed by TI+ in Tl:CsI. The decay time of the Tl:CsI/KI/KCl eutectic was 313 ns, and its light output was estimated to be 22,000 photons/MeV. [ABSTRACT FROM AUTHOR]

Luminescence and scintillation characteristics of Mg2+-codoped (Lu x Gd 3-x)Al 2.4 Ga 2.6 O 12 :Ce (x = 0.2–0.8) garnet crystals grown by the micro-pulling down method are investigated. The Ce3+ 5d 1 → 4f luminescence is blue-shifted with increasing Lu content due to the decrease in crystal field splitting of the 5 d levels. With increasing Lu content, the shortening of scintillation decay time accompanied with a decrease of LY value as measured at room temperature can be explained by thermal ionization of the Ce3+ 5d 1 excited state. Co-doping with Mg2+ results in the shortening of scintillation decay time, the reduction of LY value and afterglow intensity. At low temperature the radioluminescence quenching is observed in correlation with large thermoluminescence peaks, which can be attributed to the localization of electrons at intrinsic shallow traps. • Luminescence and scintillation of (Lu,Gd) 3 Al 2.4 Ga 2.6 O 12 :Ce, Mg crystals are investigated. • Temperature dependence of photo-and radioluminescence are presented. • Luminescence quenching above RT can be caused by thermal ionization. • Afterglow and low-temperature TL characteristics are investigated. [ABSTRACT FROM AUTHOR]

We report the absorption and emission properties of neodymium (Nd3+)-doped APLF glasses [20Al(PO 3) 3 -80LiF + x NdF 3 , x = 0.5–2.0 mol%] as potential vacuum ultraviolet (VUV) scintillator materials due to their interconfigurational 4f25d transitions which have not yet been investigated. The Nd3+-doped APLF glasses exhibit absorption and emission peaks from the VUV to the near-infrared (NIR) regions which correspond to the different interconfigurational 4f25d and intraconfigurational 4f3 transitions of Nd3+ ions. Detailed analysis of the absorption and emission spectra reveals that the Nd3+-doped glass has a disordered structure and low symmetry, as expected from amorphous materials. However, the most important feature of these glasses is their electric-dipole allowed 4f25d → 4f3 (4I 9/2) broadband emissions, between two configurations of opposite parity, around 187 nm (VUV) whose ~ 5.0 ns decay times are faster than known Nd3+-doped scintillators. At room temperature (RT), the absorption edge located around 192 nm overlaps with this VUV emission indicating that self-absorption primarily limits the emission intensity. This overlap could potentially be minimized by working at low temperatures and doping with higher (>2.0 mol%) concentrations. Despite the presence of self-absorption, the fast emission decay times from the 4f25d excited state make the Nd3+-doped APLF glasses promising new VUV scintillator materials for high-counting-rate fast neutron detection. • Nd3+-doped APLF glasses are prepared by melt-quenching method. • Interconfigurational and intraconfigurational transitions of Nd3+ ions are observed. • Interconfigurational 4f25d transitions of Nd3+-doped APLF glasses are investigated. • The electric-dipole allowed broadband VUV emissions have ~ 5.0 ns decay times. • Nd3+-doped APLF glasses are promising new VUV scintillator materials. [ABSTRACT FROM AUTHOR]

The scintillators with Ce luminescent centers are widely used for radiation detection. In this study, we focused on the Ce 2 Si 2 O 7 pyrosilicate scintillator and evaluated its optical and scintillation properties. From the result of the temperature dependence of quantum yield of Ce 2 Si 2 O 7 under excitation into the Ce3+ 4f-5d 1 transition, it was revealed that at 300°C the Ce 2 Si 2 O 7 had a quantum yield of approximately 40% of that at the room. In addition, Ce 2 Si 2 O 7 had a light output of 9,400 ± 800 photons/MeV and fast decay time (~34 ns) at room temperature, and therefore, it has potential for application in radiation detection. • Ce 2 Si 2 O 7 single crystal was grown by the micro-pulling-down method. • Optical properties of Ce 2 Si 2 O 7 was investigated. • The decay time of Ce 2 Si 2 O 7 was accelerated compared with Ce-doepd (La,Gd) 2 Si 2 O 7. [ABSTRACT FROM AUTHOR]

Single crystal of the mixed-halogen compound Cs 2 HfCl 3 Br 3 was grown by the vertical Bridgman method, and we investigated its crystal structure and optical properties. Single-crystal X-ray diffraction and energy dispersive X-ray spectroscopy analyses indicated the chemical composition to be Cs 2 Hf(Cl 0.578(6) Br 0.422(6)) 6 (= Cs 2 HfCl 3.47(4) Br 2.53(4) , approximately Cs 2 Hf(Cl 0 58 Br 0.42) 6) where the number in the parentheses denotes the estimated standard deviation in the last digit. Cs 2 Hf(Cl 0.58 Br 0.42) 6 was found to have a cubic F m 3 ‾ m potassium hexachloroplatinate structure consisting of Cs+ cations and Hf(Cl 0. 58 Br 0.42) 6 2− anions. The emission peak of Cs 2 HfCl 3 Br 3 was red-shifted by Br substitution, and the photoluminescence decays of Cs 2 HfCl 3 Br 3 were accelerated when compared to those of Cs 2 HfCl 6. Cs 2 HfCl 3 Br 3 had an emission peak at 450 nm under X-ray irradiation, while under UV-excitation, two photoluminescence emission peaks at 420 and 525 nm were observed. The decay profile of the 420-nm emission band had a single-exponential component with a decay time of 1.95 ± 0.01 μs under the 280-nm-excitation. On the other hand, 525-nm-emisison had two decay components of 0.28 ± 0.03 μs (11%) and 6.54 ± 0.03 μs (89%) under 305-nm-photons excitation. • Crystal growth and luminescence properties of Cs2HfCl3Br3 were investigated. • The crystal structure was refined as a cubic F m 3 ‾ m potassium hexachloroplatinate structure via the single-crystal X-ray diffraction measurement. • Cs2HfCl3Br3 showed 450 nm emission under X-ray irradiation. • Cs2HfCl3Br3 had two photoluminescence bands at 420 and 525 nm. • Scintillation and photoluminescence decays were measured. [ABSTRACT FROM AUTHOR]

• W co-doped Ce:Gd 3 Ga 3 Al 2 O 12 with 30–60 mm length grown by micro-pulling down method. • Light yield value was increased by small amount (200–1000 ppm) of W co-doping. • When the co-doping concentration of W was higher than 1000 ppm, the light yield decreased. Single crystal scintillators are extensively used in various radiation detection applications and their scintillation performances can be improved via co-doping. Therefore, in this study, tungsten-ion co-doped Ce:Gd 3 (Ga,Al) 5 O 12 (Ce:GGAG) crystals were grown using the micro-pulling-down (μ-PD) method to investigate the effects of co-doping on their scintillation properties. The relationships between the W concentration, optical and luminescence properties, and radiation response of the W-co-doped Ce:GGAG crystals were evaluated. The W-co-doped Ce 0.5%:Gd 3 Ga 3 Al 2 O 12 single crystals of diameter 3 mm and length 30–60 mm were grown by the μ-PD method. The light yield increased at W concentrations of 200 and 500 ppm and decreased at W concentrations above 1000 ppm. There was no significant change in the fast decay component of scintillation. [ABSTRACT FROM AUTHOR]

• Phase diagram of BaI 2 -LuI 3 system was created and it was eutectic type diagram. • BaI 2 -LuI 3 system had an eutectic point around 77.5 mol%BaI 2 /22.5 mol%LuI 3. • BaI 2 /LuI 3 eutectic crystal and Ce-doped BaI 2 /LuI 3 eutectic scintillator were grown. • The BaI 2 /LuI 3 eutectic crystal was composed of LuI 3 rod phase and BaI 2 matrix phase. The phase diagram of the BaI 2 -LuI 3 system was created using powder X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analysis, and a eutectic scintillator crystal was grown by the halide-vertical bridgman (H-VB) method. The results of XRD patterns and DSC curves showed that the phase diagram of the BaI 2 -LuI 3 system had a eutectic point around 77.5 mol% BaI 2 /22.5 mol% LuI 3 , and no new compound was generated from BaI 2 and LuI 3. The 77.5 mol% BaI 2 /22.5 mol% LuI 3 eutectic crystal was composed of BaI 2 in rod phase and LuI 3 in matrix phase. In addition, the Ce-doped 77.5 mol% BaI 2 /22.5 mol% LuI 3 specimen showed emission peaks originating from 5d–4f transition of Ce3+ ion in the X-ray radioluminescence (XRL) spectrum and the decay time under γ-ray irradiation was approximately 38 ns. [ABSTRACT FROM AUTHOR]

• Feasibility of the growth of LYSO, YSO, LuAG, YAG and GAGG by EFG was studied. • Aluminate such LuAG and YAG had the least reactivity with Mo metal. • Ce:LuAG with 320 mm length were grown by 4 multiple EFG using Mo crucible and die. • Light yield value was high and nearly constant within 25,000–27,200 photon/MeV. Edge defined Film Fed Growth (EFG) method with molybdenum (Mo) crucible and die was studied for the growth of several oxide-based single crystals. At first, reactivity between the molybdenum (Mo) metal and oxide melts of Ce:(Lu,Y) 2 SiO 5 (LYSO) Ce:Y 2 SiO 5 (YSO), Ce:Gd 3 (Al,Ga) 5 O 12 (GAGG), Ce:Lu 3 Al 5 O 12 (LuAG), Ce:Y 3 Al 5 O 12 (YAG) was investigated. The experimental and calculation results on the reactivity with Mo show that the aluminum garnets (LuAG, YAG) had the smallest reactivity with Mo metal. On the contrary, GAGG showed the strongest reaction with Mo. Then, the multiple-die grown shaped single crystal growth of Ce:LuAG was demonstrated by EFG method. Single crystal plates up to 320 mm in length were grown successfully. The homogeneity of dopant distribution, Mo contamination, luminescence and scintillation responses of the grown crystals were evaluated. [ABSTRACT FROM AUTHOR]

Ca 3 Ta(Ga 1- x Sc x ) 3 Si 2 O 14 (CTGSS) single crystals with various Sc concentrations ( x = 0, 0.1, 0.2, 0.3, and 0.4) were grown by the micro-pulling-down method and their structure and chemical composition were evaluated. Through the powder X-ray diffraction (XRD) measurement and backscattered electron (BSE) imaging, it was demonstrated that all the CTGSS crystals with different Sc concentration were successfully grown as langasite-type structure although some secondary phases were observed for the crystals with x = 0.2, 0.3 and 0.4. Lattice parameters calculated from the powder XRD pattern generally increased with Sc substitution. Measured parameters for CTGSS crystal with x = 0.1 were larger permittivity ε 11 T / ε 0 and lower electromechanical coupling coefficient k 12 and piezoelectric constant d 11 than those for CTGS crystal with x = 0. It was also suggested that piezoelectric constant | d 14 | became larger due to the Sc substitution. [ABSTRACT FROM AUTHOR]

Introduction: In treating nonunion, the removal of a broken nail is often difficult. We report a technique for removing a broken Kuntscher intramedullary nail. In this technique, a chisel is inserted into the lumen of the intramedullary nail, and the nail is rotated., Case Presentation: A 57-year-old man presented to our hospital with femoral diaphyseal nonunion lasting 17 years after injury. The patient suffered a right femoral diaphyseal fracture at 40 years old and was treated with a Kuntscher intramedullary nail. The patient underwent two additional surgeries at another hospital for the nonunion; however, the nonunion did not heal, and the intramedullary nail broke. The patient was diagnosed with noninfectious hypertrophic nonunion and underwent surgery. We resected part of the lateral cortex of the femoral diaphyseal nonunion and reached the proximal end of the broken Kuntscher intramedullary nail. We inserted a chisel into the lumen of the intramedullary nail, held the chisel using pliers, and rotated the nail to separate it from the surrounding tissue. The proximal side of the broken intramedullary nail was easily removable. One year after surgery, the right femoral pseudarthrosis was healed with a bony callus., Discussion: This procedure was possible because of the structural characteristics of the intramedullary nail, which is straight without curvature but has grooves., Conclusion: We removed a broken Kuntscher intramedullary nail without causing an iatrogenic fracture by fenestration of the cortex and rotation of the nail., Competing Interests: Conflict of interest statement None., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Introduction: Preoperative estimations of blood loss are important when planning surgery for cervical spine injuries in older adults. The association between ankylosis and blood loss in perioperative management is of particular interest. This multicenter database review aimed to evaluate the impact of ankylosis on surgical blood loss volume in elderly patients with cervical spine injury., Methods: The case histories of 1512 patients with cervical spine injury at among 33 institutions were reviewed. After the exclusion of patients without surgery or whose blood loss or ankylosis status was unclear, 793 participants were available for analysis. Differences in blood loss volume were compared between the Ankylosis (+) group with ankylosis at the cervical level and the Ankylosis (-) group without by the inverse probability of treatment weighting (IPTW) method using a propensity score., Results: Of the 779 patients (mean age: 75.0±6.3 years) eligible for IPTW calculation, 257 (32.4%) had ankylosis at the cervical level. The mean blood loss volume was higher in Ankylosis (+) patients than in Ankylosis (-) patients (P<0.001). This difference did not reach statistical significance when weighted by background factors, with mean blood loss of 244 mL and 188 mL, respectively, after adjustment., Conclusions: This study revealed that ankylosis was significantly associated with increased blood loss volume when unadjusted by surgical time. Elderly patients with cervical spine injury accompanied by ankylosis appear predisposed to higher bleeding and severe hemorrhage, both as a result of the condition and their particular demographic characteristics., Competing Interests: Conflicts of Interest: The authors declare that there are no relevant conflicts of interest., (Copyright © 2024 The Japanese Society for Spine Surgery and Related Research.)

Study Design: Retrospective cohort study., Objectives: To define the prognosis and predictive factors for neurological improvement in older patients with incomplete spinal cord injury (SCI) of American Spinal Injury Association Impairment Scale grade C (AIS-C)., Settings: Multi-institutions in Japan., Methods: We included patients aged ≥65 years with traumatic SCI of AIS-C who were treated conservatively or surgically with >3 follow-up months. To identify factors related to neurological improvement, patients were divided into three groups according to their neurological status at the final follow-up, with univariate among-group comparisons of demographics, radiographic, and therapeutic factors. Significant variables were included in the multivariate logistic regression analysis., Results: Overall, 296 older patients with SCI of AIS-C on admission were identified (average age: 75.2 years, average follow-up: 18.7 months). Among them, 190 (64.2%) patients improved to AIS-D and 21 (7.1%) patients improved to AIS-E at final follow-up. There were significant among-group differences in age (p = 0.026), body mass index (p = 0.007), status of pre-traumatic activities of daily living (ADL) (p = 0.037), and serum albumin concentrations (p = 0.011). Logistic regression analysis showed no significant differences in variables in the stratified group of patients who improved to AIS-D. Meanwhile, serum albumin was a significant variable in patients who improved to AIS-E (p = 0.026; OR: 6.20, pre-traumatic ADL was omitted due to data skewness)., Conclusions: Most older patients with incomplete AIS-C SCI demonstrated at least 1 grade of neurological improvement. However, <10% of patients achieved complete recovery. Key predictors of complete recovery were high serum albumin levels on admission and independent pre-traumatic ADL., Sponsorship: No funding was received for this study., (© 2024. The Author(s), under exclusive licence to International Spinal Cord Society.)

Multiferroic materials, particularly those possessing simultaneous electric and magnetic orders, offer a platform for design technologies and to study modern physics. Despite the substantial progress and evolution of multiferroics, one priority in the field remains to be the discovery of unexplored materials, especially those offering different mechanisms for controlling electric and magnetic orders 1 . Here we demonstrate the simultaneous thermal control of electric and magnetic polarizations in quasi-two-dimensional halides (K,Rb) 3 Mn 2 Cl 7 , arising from a polar-antipolar transition, as evidenced using both X-ray and neutron powder diffraction data. Our density functional theory calculations indicate a possible polarization-switching path including a strong coupling between the electric and magnetic orders in our halide materials, suggesting a magnetoelectric coupling and a situation not realized in oxide analogues. We expect our findings to stimulate the exploration of non-oxide multiferroics and magnetoelectrics to open access to alternative mechanisms, beyond conventional electric and magnetic control, for coupling ferroic orders., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Study Design: Retrospective Cohort Study., Objective: The purpose of this study was to investigate the prognosis of respiratory function in elderly patients with cervical spinal cord injury (SCI) and to identify predictive factors., Methods: We included 1353 cases of elderly cervical SCI patients collected from 78 institutions in Japan. Patients who required early tracheostomy and ventilator management and those who developed respiratory complications were defined as the respiratory disability group. Patients' background characteristics, injury mechanism, injury form, neurological disability, complications, and treatment methods were compared between the disability and non-disability groups. Multiple logistic regression analysis was used to examine the independent factors. Patients who required respiratory management for 6 months or longer after injury and those who died of respiratory complications were classified into the severe disability group and were compared with minor cases who were weaned off the respirator., Results: A total of 104 patients (7.8%) had impaired respiratory function. Comparisons between the disabled and non-disabled groups and between the severe and mild injury groups yielded distinct trends. In multiple logistic regression analysis, age, blood glucose level, presence of ossification of posterior longitudinal ligament (OPLL), anterior vertebral hematoma, and critical paralysis were selected as independent risk factors., Conclusion: Age, OPLL, severe paralysis, anterior vertebral hematoma, hypoalbuminemia, and blood glucose level at the time of injury were independent factors for respiratory failure. Hyperglycemia may have a negative effect on respiratory function in this condition., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Study Design: Retrospective multicenter study., Objective: The purpose of this study was to compare the prognosis of elderly patients with injuries related to cervical diffuse idiopathic skeletal hyperostosis (cDISH) to matched control for each group, with and without fractures., Methods: The current multicenter study was a retrospective analysis of 140 patients aged 65 years or older with cDISH-related cervical spine injuries; 106 fractures and 34 spinal cord injuries without fracture were identified. Propensity score-matched cohorts from 1363 patients without cDISH were generated and compared. Logistic regression analysis was performed to determine the risk of early mortality for patients with cDISH-related injury., Results: Patients with cDISH-related injuries with fracture did not differ significantly in the incidence of each complication and ambulation or severity of paralysis compared to matched controls. In patients with cDISH-related injury without fracture, those who were nonambulatory at discharge comprised 55% vs 34% of controls, indicating significantly poorer ambulation in those with cDISH-related injuries ( P = .023). There was no significant difference in the incidence of complications and ambulation or paralysis severity at 6 months as compared with controls. Fourteen patients died within 3 months. Logistic regression analysis identified complete paralysis (odds ratio [OR] 36.99) and age (OR 1.24) as significant risk factors for mortality., Conclusions: The current study showed no significant differences in the incidence of complications, ambulation outcomes between patients with cDISH-related injury with fracture and matched controls, and that the ambulation at discharge for patients with cDISH-related injury without fractures were significantly inferior to those of matched controls., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Study Design: Retrospective multicenter study., Objectives: To investigate the neurological outcomes of older individuals treated with surgery versus conservative treatment for cervical spinal cord injury (CSCI) without bone injury., Setting: Thirty-three medical institutions in Japan., Methods: This study included 317 consecutive persons aged ≥65 years with CSCI without bone injury in participating institutes between 2010 and 2020. The participants were followed up for at least 6 months after the injury. Individuals were divided into surgery (n = 114) and conservative treatment (n = 203) groups. To compare neurological outcomes and complications between the groups, propensity score matching of the baseline factors (characteristics, comorbidities, and neurological function) was performed., Results: After propensity score matching, the surgery and conservative treatment groups comprised 89 individuals each. Surgery was performed at a median of 9.0 (3-17) days after CSCI. Baseline factors were comparable between groups, and the standardized difference in the covariates in the matched cohort was <10%. The American Spinal Injury Association (ASIA) impairment scale grade and ASIA motor score (AMS) 6 months after injury and changes in the AMS from baseline to 6 months after injury were not significantly different between groups (P = 0.63, P = 0.24, and P = 0.75, respectively). Few participants who underwent surgery demonstrated perioperative complications such as dural tear (1.1%), surgical site infection (2.2%), and C5 palsy (5.6%)., Conclusion: Conservative treatment is suggested to be a more favorable option for older individuals with CSCI without bone injuries, but this finding requires further validation., (© 2022. The Author(s), under exclusive licence to International Spinal Cord Society.)

Introduction: In elderly patients with cervical spinal cord injury, comorbidities such as cardiovascular and cerebrovascular diseases are common, with frequent administration of antiplatelet/anticoagulant (APAC) drugs. Such patients may bleed easily or unexpectedly during surgery despite prior withdrawal of APAC medication. Few reports have examined the precise relationship between intraoperative blood loss and history of APAC use regarding surgery for cervical spine injury in the elderly. The present multicenter database survey aimed to answer the question of whether the use of APAC drugs affected the amount of intraoperative blood loss in elderly patients with cervical spinal cord trauma., Methods: The case histories of 1512 patients with cervical spine injury at 33 institutes were retrospectively reviewed. After excluding cases without spinal surgery or known blood loss volume, 797 patients were enrolled. Blood volume loss was the outcome of interest. We calculated propensity scores using the inverse probability of treatment weighting (IPTW) method. As an alternative sensitivity analysis, linear mixed model analyses were conducted as well., Results: Of the 776 patients (mean age: 75.1±6.4 years) eligible for IPTW calculation, 157 (20.2%) were taking APAC medications before the injury. After weighting, mean estimated blood loss was 204 mL for non-APAC patients and 215 mL for APAC patients. APAC use in elderly patients was not significantly associated with surgical blood loss according to the IPTW method with propensity scoring or linear mixed model analyses. Thus, it appeared possible to perform surgery expecting comparable blood loss in APAC and non-APAC cases., Conclusions: This multicenter study revealed no significant increase in surgical blood loss in elderly patients with cervical trauma taking APAC drugs. Surgeons may be able to prioritize patient background, complications, and preexisting conditions over APAC use before injury when examining the surgical indications for cervical spine trauma in the elderly., Competing Interests: Conflicts of Interest: The authors declare that there are no relevant conflicts of interest., (Copyright © 2022 by The Japanese Society for Spine Surgery and Related Research.)