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Tb3+‐doped and Eu3+/Tb3+ co‐doped transparent glass ceramics containing Na3Gd(PO4)2 crystal phase were prepared by melt crystallization. The types of crystals, grain size, and optical transmittance of the samples were investigated by X‐ray diffraction (XRD), scanning electron microscope (SEM), and UV visible absorption spectrometer. The effect of different heat treatment time on grain size, crystal morphology, and light transmittance was also studied. The luminescence performance of transparent glass ceramics was systematically studied by the excitation spectrum, emission spectrum, and the fluorescence lifetime. The optimal doping concentration of Tb3+ doped and Eu3+/Tb3+ co‐doped were determined. When the mole percent concentration of Tb4O7 was 0.4%, the strongest green light was obtained at 546 nm (5D4 → 7F5). Meanwhile, the energy transfer process between Eu3+ and Tb3+ was discussed. Under the excitation of 374 nm, white light can be obtained by adjusting the concentration ratio of Eu3+ and Tb3+. [ABSTRACT FROM AUTHOR]

Based on the field test, the bearing characteristics of uplift piles in the sand strata were studied. The failure mechanism of rock socketed piles were analyzed. The prediction formula of the ultimate uplift bearing capacity of rock socketed piles were proposed. The calculation results, test values and code calculation values were compared. The results show that the uplift load and displacement curve of rock socketed pile is steep. Increasing the pile length can effectively increase the bearing capacity, but has limited impact on the displacement of pile top. The test relative displacement of the pile and rock is 20 ~ 25 mm, and the side resistance of the moderately weathered sandstone layer reaches the limit. The ultimate uplift side resistance is 925. 4 ~ 961. 3 kPa. When the pile strength is higher than the rock mass around, the uplift bearing capacity of the pile are provided by the shear strength of the rock around the pile. The limit side resistance of piles can be equivalent to the shear strength of the rock around the pile. The code calculation value are conservative, which is 0. 18 ~0. 39 times of the test value. [ABSTRACT FROM AUTHOR]

The Tb3+‐doped transparent glass ceramics containing Al4Ti2SiO12 crystal are synthesized by the melt‐solid‐crystallization method. The optimal heat treatment conditions for the glass ceramic samples are determined to be 750°C, 1.5 h based on differential scanning calorimeter, X‐ray diffractometer, scanning electron microscope, and light transmittance curve. The luminescence properties of the glass ceramics samples are characterized by a fluorescence spectrometer. The emission spectrum revealed that the dominant emission is green attributed to Tb3+, the optimal doping concentration is 0.3%. And the thermal quenching activation energy of 0.3% Tb3+‐doped glass ceramics is 0.2554 eV, while the relative sensitivity is 1.50% K−1 at 298 K and the absolute sensitivity is 2.27×10−2 K−1 at 418 K through variable temperature fluorescence spectroscopy test and a series of calculations. These findings demonstrate the excellent stability and temperature sensitivity of glass ceramics, thereby highlighting their potential for use in green lighting and temperature sensing applications. [ABSTRACT FROM AUTHOR]

Tb3+‐doped and Eu3+/Tb3+ co‐doped transparent glass ceramics containing Na3Gd(PO4)2 crystal phase were prepared by melt crystallization. The types of crystals, grain size, and optical transmittance of the samples were investigated by X‐ray diffraction (XRD), scanning electron microscope (SEM), and UV visible absorption spectrometer. The effect of different heat treatment time on grain size, crystal morphology, and light transmittance was also studied. The luminescence performance of transparent glass ceramics was systematically studied by the excitation spectrum, emission spectrum, and the fluorescence lifetime. The optimal doping concentration of Tb3+ doped and Eu3+/Tb3+ co‐doped were determined. When the mole percent concentration of Tb4O7 was 0.4%, the strongest green light was obtained at 546 nm (5D4 → 7F5). Meanwhile, the energy transfer process between Eu3+ and Tb3+ was discussed. Under the excitation of 374 nm, white light can be obtained by adjusting the concentration ratio of Eu3+ and Tb3+. [ABSTRACT FROM AUTHOR]

• Sm3+, Eu3+ doped NaNbO 3 glass ceramics were prepared and red light emission was realized. • The energy transfer efficiency was 49.44 % for 0.8 % Sm3+, 1.0 % Eu3+ doped NaNbO 3 glass ceramics. • The color purity was 95.7 % for 0.8 % Sm3+, 1.0 % Eu3+ doped NaNbO 3 glass ceramics. • The thermal quenching activation energy of glass ceramics was 0.236 eV and color offset value was 1.83 × 10−3, indicating good thermal and color stability. The lack of red light in commercial white LEDs limits the application in solid-state lighting. So preparing high-performance red luminescent materials is currently the main challenge. In this study, a series of Sm3+, Eu3+ co-doped glass ceramics containing NaNbO 3 crystalline phase were successfully prepared using the melt-curing-crystallization method. By differential scanning calorimetry analysis, X-ray diffraction analysis, scanning electron microscopy analysis and light transmittance analysis, the optimal heat treatment conditions for glass ceramics were determined to be 570 °C for 90 min. With the increase of Eu3+ concentration, the emission peaks of Sm3+ at 565 nm, 602 nm and 649 nm gradually decreased, indicating that there was energy transferred between Sm3+ and Eu3+. The emission intensity of the 0.8 mol% Sm3+, 1.0 mol% Eu3+ co-doped NaNbO 3 glass ceramics at 438 K still reaches 87 % of room temperature. Sm3+, Eu3+ co-doped NaNbO 3 glass ceramics have potential application value in the field of white LEDs. [ABSTRACT FROM AUTHOR]

In this paper, Tb3+-Sm3+ co-doped glass ceramics with K 3 Gd(PO 4) 2 crystal phase were successfully prepared by methods of melting curing crystallization. The optimal heat treatment conditions for the samples were determined to be held for 1.5 h at 750 °C by combining differential scanning calorimeter (DSC), x-ray diffraction (XRD) and scanning electron microscope (SEM). Under this condition, glass ceramics still have a high transmittance in the range of 400∼700 nm, up to 80 %. It was calculated that the optical band gap value of glass ceramic is smaller than that of glass, indicating that the sample structure was changed by heat treatment. Fluorescence lifetime and Dexter's theory demonstrate that Tb3+ transfers energy to Sm3+. By fixing the concentration of Tb3+ and changing the doping concentration of Sm3+, the luminous color of glass ceramics can be adjusted. At 458 K, the fluorescence intensity of Tb3+ and Sm3+ decreased to 89 % and 85 % of that at 298 K. Study shows that the prepared glass ceramics have potential applications in white light emitting diodes (WLEDs). • The Sm3+-Tb3+ doped glass ceramic containing K 3 Gd(PO 4) 2 was synthesized. • The transmittance of glass ceramic can reach 80 % in the visible region. • At 458 K, the luminous intensity of glass ceramics can reach more than 80 % of room temperature. • The thermal quenching activation energy of samples can reach 0.3057 eV. • The prepared glass ceramics can achieve tunable emission in the visible region. [ABSTRACT FROM AUTHOR]

• The Ho3+-Yb3+ doped glass ceramic containing LaTiO 3 was synthesized. • The transmittance of glass ceramic can reach 79% in the visible region. • The color purity of 0.20 %Ho3+-0.30 %Yb3+ co-doped glass ceramics reaches up to 98.03 %. By using melt solidification crystallization method, Ho3+-Yb3+ co-doped transparent glass ceramics (GCs) containing LaTiO 3 microcrystal were successfully prepared. The structure of the GCs was characterized by X-ray diffraction (XRD), which proved that LaTiO 3 microcrystal was precipitated in the precursor glass (PG). The structures of PG and GCs were studied by infrared spectrum, which showed that a new absorption peak appeared in the GCs, which was attributed to the stretching vibration of the Ti-O bond in the [TiO 6 ] octahedral group, and it further demonstrated the precipitation of the LaTiO 3 microcrystal. By studying the up-conversion luminescence (UCL) properties, it is found that there were three emission peaks at 546, 652 and 484 nm, which are attributed to the 5F 4 /5S 2 → 5I 8 , 5F 5 → 5I 8 and 5F 3 → 5I 8 transitions of Ho3+, respectively, and the optimal doping concentrations of Ho3+ and Yb3+ were determined. The chrominance coordinate of Ho3+-Yb3+ co-doped glass ceramic (GC) is situated in the green light area and the color purity is as high as 98.03 %. The researches above show that Ho3+-Yb3+ co-doped GCs with LaTiO 3 microcrystal have a wide application prospect in green luminescence. [ABSTRACT FROM AUTHOR]

By using the melt crystallization method, Tb 4 O 7 −MnO 2 co-doped glass-ceramics containing Y 2 Sn 2 O 7 were synthesized. The heat treatment for glass-ceramics was determined to be 700 °C/1.5 h using differential scanning calorimetry analysis, X-ray diffraction, scanning electron microscopy, and light transmittance curves. FTIR spectroscopy further confirmed the precipitation of the Y 2 Sn 2 O 7. Although MnO 2 was used as the Mn source in this experiment, the glass-ceramic showed the luminescent properties of Mn2+. The emission spectra and fluorescence decay curves of Tb 4 O 7 −MnO 2 co-doped glass-ceramics demonstrate the energy transfer phenomenon of Tb3+→Mn2+. When the doping concentration of MnO 2 increases, the glass-ceramics can realize tunable luminescence from green light to yellow light to orange light. At 473 K, the luminescence intensity of Tb3+ and Mn2+ were 84.3% and 33.0% of those at room temperature. In terms of absolute and relative sensitivity, the maximum values for glass-ceramics were 1.18 × 10−2 K−1 and 1.52% K−1. The minimum temperature resolution is 0.05 K at 298 K. It is demonstrated that the prepared Tb 4 O 7 −MnO 2 co-doped glass-ceramics containing Y 2 Sn 2 O 7 have a promising application in the field of optical temperature measurement. [ABSTRACT FROM AUTHOR]

• Transparent glass-ceramic containing NaLaSiO 4 crystal phase was prepared there first time. • The Rietveld refinement with XRD patterns confirmed Ho3+ ions entering the lattice by replacing sites of La. • Changing the concentration of Yb3+ can convert the emission of Ho3+ from green to red. • With the concentration of 0.4% Ho3+−1.1% Yb3+, red light with 98.9% color purity was achieved. By using the melt-annealing method, silicate precursor glasses were prepared. Optimal heat treatment conditions for glass ceramics at 610 °C for 90 min were established through a series of tests. Glass ceramics containing NaLaSiO 4 crystals with β-K 2 SO 4 structure were successfully synthesized after heat treatment. XRD patterns of glass ceramics were successfully fitted using Rietveld refinement, with rare earth ions entering the lattice by replacing sites of La resulting in a reduction in cell volume. A tunable emission from green light to red light was achieved by varying the Yb3+ doping concentration. By varying the concentration of Ho3+, the intensity of the up-conversion emission was significantly increased while maintaining high color purity in red light. The optimal concentration of Ho3+ was 0.4%, when the red light color purity was 98.9%. These results indicate that glass ceramics containing NaLaSiO 4 crystals co-doped with Ho3+-Yb3+ could be used for up-conversion color-tunable emission and red luminescence. [ABSTRACT FROM AUTHOR]

Upconversion (UC) phosphors KY(MoO 4 ) 2 : xYb 3+ , 2%Er 3+ have been synthesized by a typical hydrothermal process. The UC luminescence, thermal sensing and optical heating properties have been investigated in the paper. From the UC luminescence spectra, the phosphors show two intense green emissions at 532 nm and 553 nm under the excitation of 980 nm, which can be used to discuss the temperature sensing performance with the temperature ranging 313–563 K. The maximum sensitivity is obtained around 0.0163 K −1 at 523 K. Additionally, the laser excitation heating effect was also explored, the lattice temperature varies from 308.2 to 426.2 K with increasing of power densities from 12.73 to 82.80 W/cm 2 . The experimental results indicate that the KY(MoO 4 ) 2 : Yb 3+ /Er 3+ phosphor may be used as potential material with thermometric and optical heating characters. [ABSTRACT FROM AUTHOR]

By melt annealing technique, Er3+-Yb3+ co-doped precursor glass (PG) was prepared. Glass ceramics (GCs) containing KZnPO 4 crystal phase with tridymite structure were obtained by heat treatment of PG. The optimum heat treatment conditions of GCs are 670 °C for 60 min. Under these conditions, the average grain size of GC is about 205 nm, and the light transmittance in the visible region is about 80%. Through the analysis of the Rietveld refinement results of XRD, the lattice constants a and b of KZnPO 4 crystal decreased from 18.155 Å to 18.109 Å, and c decreased from 8.504 Å to 8.451 Å. Therefore, it is inferred that Er3+ and Yb3+ replace the Zn2+ in the lattice. The green up-conversion luminescence of GC is about 10 times that of PG excited by 980 nm laser. The optimal doping concentrations of Er3+ and Yb3+ in GCs are 0.5% and 1.0%, respectively. The calculation results of chromaticity coordinates show that Er3+-Yb3+ co-doped GCs with KZnPO 4 crystal phase is a promising green up-conversion luminescent material. • Er3+-Yb3+ doped transparent glass-ceramics containing KZnPO 4 crystal phase were prepared. • The light transmittance of glass-ceramic in the visible range can reach 80%. • The green up-conversion emission of glass-ceramics was about 10 times higher than that of precursor glass. • The color purity of 0.5%Er3+-1.0%Yb3+ co-doped glass-ceramic can reach 88.51%. [ABSTRACT FROM AUTHOR]

Tb 4 O 7 -Sm 2 O 3 co-doped transparent glass ceramics (GCs) containing Ba 3 Gd(PO 4) 3 crystalline phase were prepared by melt crystallization. The heat treatment condition for GCs was determined to be 740 ℃/2 h by differential scanning calorimetry, X-ray diffraction, scanning electron microscopy and transmittance curves. The optical energy bandgap value of glass ceramics is smaller than that of glass. The fluorescence lifetime and Dexter theory demonstrated the energy transfer from Tb3+ to Sm3+. The luminescence color can be adjusted in the white range when the Sm 2 O 3 doping concentration is changed. At 473 K, the luminous intensity of Tb3+ and Sm3+ can be maintained 86.63 % and 89.36 % of that at room temperature, respectively. The maximum values of the absolute and relative sensitivity of the glass ceramics are 0.00525 K−1 and 2.33 % K−1, respectively. This study shows that the obtained luminescent glass ceramics have potential applications in ultraviolet excited white light emitting diodes and optical thermometry. • Tb 4 O 7 -Sm 2 O 3 doped glass-ceramics containing Ba 3 Gd(PO 4) 3 is synthesized. • The existence of the energy transfer from Tb3+ to Sm3+ was certified. • The tunable emission in the white light range was realized by adjusting the doped concentration. • Tb 4 O 7 -Sm 2 O 3 doped glass-ceramics had good optical temperature sensing performance. [ABSTRACT FROM AUTHOR]

• The Dy3+ co-doped glass ceramic containing Ba 0.808 (Al 1.71 Si 2.29)O 8 is synthesized. • The transmittance of glass ceramic can reach 76% in the visible region. • The critical distance of Dy3+ is 3.437 nm. Dy3+ doped transparent glass ceramics containing Ba 0.808 (Al 1.71 Si 2.29)O 8 crystal phase are successfully prepared by the melting crystallization method. Through differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscope (SEM), the optimum heat treatment condition is determined to be 680 ℃/1.5 h. The absorption spectra of the glass and glass-ceramic samples are used to calculate their indirect allowable optical band gaps. It is found that the optical band gap of glass ceramics narrowed. The emission spectrum shows three emission peaks at 484 nm, 576 nm, and 669 nm, corresponding to the blue, yellow, and red emission of Dy3+. The optimal doping concentration of Dy 2 O 3 is 0.45 mol% , the Correlated Color Temperature (CCT) of 4540 K, and the CIE chromaticity coordinates of (0.3642, 0.3924), which is close to warm white light. The reason for the concentration quenching is the electrical multipolar interaction between Dy3+. [ABSTRACT FROM AUTHOR]

• Dy3+-Eu3+ co-doped glass-ceramics containing ZnMoO 4 was prepared. • The existence of the energy transfer from Dy3+ to Eu3+ was certified. • Warm white light were achieved by adjusting the doped concentration. Dy3+-Eu3+ co-doped glass-ceramics (GCs) containing ZnMoO 4 were successfully prepared. The temperature range of heat treatment was preliminarily determined by differential scanning calorimeter (DSC) and thermogravimetry (TG). The crystalline phase was determined by X-ray diffraction (XRD), the structural feature was analyzed on the basis of Rietveld refinement, the morphology was observed by scanning electron microscopy (SEM), the absorption coefficients were calculated by light transmission curves. Combined with the above analysis, the optimal heat treatment condition was discussed. Through the fluorescence spectra and decay curve, there existed an energy transfer between Dy3+ and Eu3+, and the energy transfer efficiency from Dy3+ to Eu3+ increased with the increase of Eu3+ concentration. By calculating the critical distance and linearly fitting the data, it could be concluded that the mechanism of energy transfer was dipole-dipole interaction. With the changed of Dy3+-Eu3+ doped concentration, the color coordinates of these samples can be tuned in the white light region, and the 0.4% Dy3+-0.7% Eu3+ co-doped glass-ceramics obtained warm white light emission with low correlated color temperature (CCT). These results clearly showed that Dy3+-Eu3+ co-doped GCs containing ZnMoO 4 could be used as a potential candidate material in the field of white light-emitting diodes (w-LEDs). [ABSTRACT FROM AUTHOR]

Abstract: Glass containing B2O3–Al2O3–SiO2–Li2O–K2O was prepared by conventional melting and annealing technique, and converted to transparent glass–ceramics by controlled nucleation and crystallization process. The nucleation and crystallization temperatures were determined by differential thermal analysis. X-ray diffraction was used to determine the crystal phases. Scanning electron microscopy was used to study the glass–ceramics morphology, the grain size and distribution in the residual glass. Infrared spectroscopy was used to confirm the reorganization of amorphous solid. X-ray photoelectron spectroscopy was used to determine the valence state of element. The transmittance was measured by UV–Vis–NIR scanning spectrophotometer. Two main crystal phases including Al4B2O9 and Al20B4O36 were observed in all samples. The change in B2O3/Al2O3 ratio has little influence on the crystal types of the B2O3–Al2O3–SiO2 glass–ceramics. B atoms existed in the form of [BO3] and [BO4]. Al existed in the forms of [AlO4] and [AlO6], and forming network together with [SiO4] tetrahedron. The transmittance of BAS glass–ceramics reached 90% at visible and infrared wavelength, and cut-on absorption at ultraviolet and cut-off absorption at infrared wavelength were observed. [Copyright &y& Elsevier]

Objective: To analyze the stage characteristics in the dietary behavior improvement of college students and explore the role of social cognitive variables in the dietary behavior change based on the Health Action Process Approach., Methods: Selfmade college students' eating behavior scales, college students' dietary rating scales and social cognitive scales were used to investigate their eating behavior, dietary stages, and eating intentions. A cluster random sampling was employed to select 2100 college students in 8 colleges and universities in Shanxi Province from April to November 2015, a total of 1933 valid questionnaires were retrieved. The respondents were grade one to four undergraduates, of whom 613 were boys and 1320 were girls., Results: Cross-sectional survey result showed that the dietary behavior of college students in Shanxi Province was 118. 17 ± 15. 27. In the social cognitive variables, positive expectancy( t =-3. 98, P <0. 001) and behavioral intentions( t =-4. 03, P < 0. 001) had significant difference in gender, where girls were higher than boys. Self-efficacy, risk perception, outcome expectancy, action planning and dietary behavior all showed significant difference among preintenders, intenders and actors( P < 0. 01)., Conclusion: The action stage of dietary behavior improvement had the most students and there were different social cognitive variables at different dietary behavior stages. Researchers should implement targed health management for students at different dietary behavior stages to make their dietary behavior more reasonablely and scientifically.

Objective: To carry out a stage-matched intervention study on dietary behavior based on the Health Action Process Approach( HAPA), in order to verify the effectiveness of the intervention on improving the dietary behavior of college students., Methods: The study recruited 184 medical university 's students who were admitted between 2013 and 2015 from Shanxi, including 37 males and 147 females to participate the intervention of dietary behavioral based on HAPA from October 2015 to May 2016 by method of random sampling. They were divided into control group( 98) and intervention group( 86). No intervention was conducted on participants in the control group, differentintervention measures were applied to non-intenders, intenders and actors according to their characteristics in intervention group. Epi Data 3. 1 and SPSS 20. 0 were employed to analyze data., Results: After the stage-matched intervention, the proportion of actors in the intervention group increased from 52. 33% to 66. 28%. In the intervention group the scores of participants after intervention were significantly higher than those before intervention, and were also significantly higher after intervention than those from control group in dietary behaviors( P < 0. 001), dietary concepts( P < 0. 001), taste tendency( P < 0. 001, P = 0. 002), eating regular( P < 0. 001) and dietary habits( P = 0. 006, P < 0. 001). In the intervention group, the total scores in dietary behavior at nonintenders( t =-5. 22, P < 0. 001), intenders( t =-13. 69, P < 0. 001) and actors( t =-8. 82, P < 0. 001) after intervention were significantly higher than those before intervention., Conclusion: Stage-matched intervention based on the HAPA has a positive effect on improving the dietary behavior of college students.

Objective: To grasp research status and the revolution of Journal of Hygiene Research since started publishing, and also track research hot spots and developing trends of this field., Methods: Using the method of bibliometrics and information visualization software CiteSpace III, quantities of published literature, supported funds, institutions, authors and keywords from 6775 articles published in Journal of Hygiene Research from 1972 to 2014 were analyzed., Results: Amount of literatures published on Journal of Hygiene Research increased wave upon wave, the peak appeared in 1995. Institutions of Chinese Center for Disease Control and Prevention, such as National Institute for Nutrition and Health, Institute of Environmental Health and Related Product Safety, National Institute of Occupational Health and Poison Control and some medical colleges were the most productive. The scholars with the most number of publications were YANG Xiaoguang, YIN Shian and PIAO Jianhua, the researcher of National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention, with more than 75 articles were published. The research contents included influencing factors, related concepts, diseases, methods and objects. "mutagenicity", "apoptosis", "lead poisoning", "HPLC" and "rat" were research focuses in this field., Conclusion: There were lots of matter and cooperation in the articles published on Journal of Hygiene Research. The centers for disease control and prevention in different regions and universities pay attention to the coorperation, research teams with members of various ages collaborate and grow together, form a close, complex collaborative network among authors, which promote the development of the magazine and research fields together.