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41.
E.D. Sim Y.S. Joh J.H. Song H.L. Park S.H. Lee K. Jeong S.K. Chang 《physica status solidi b》2002,229(1):213-216
Using nitrogen radio‐frequency (RF) plasma operated in low‐pressure metal‐organic chemical vapor deposition (LP‐MOCVD), nitrogen‐doped ZnSe epilayers were grown and their optical properties were investigated. In the low‐temperature photoluminescence (PL) of nitrogen‐doped ZnSe epilayers, two emissions were observed, attributed to a nitrogen acceptor‐bound exciton (I1) at 2.792 eV and a donor–acceptor pair (DAP) at 2.70 eV. The characteristics of nitrogen acceptor‐bound excitons and DAP emissions under excitation power dependent PL spectra were discussed. From theses results, we found that nitrogen was successfully incorporated into selenium sites and then acted as an acceptor. In addition, we obtained the net acceptor concentration 1.15 × 1018 cm—3 by capacitance–voltage profiling. 相似文献
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Joh Pinnow 《Fresenius' Journal of Analytical Chemistry》1904,43(2):91-96
Ohne ZusammenfassungLaboratorium für analytische Chemie an der k. k. technischen 相似文献
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Jae-Won Lee Do-Yoon Lee Young-Soon Lee Joo-Young Yoon Sang-Chae Jeon Ju-Ho Lee Seok-Min Hong Yung-Zun Cho 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):15-23
The electrolytic reduction process in pyroprocessing of used fuel requires that fuel fragments be pre-treated to remove cesium and iodine. The effect of high temperatures and fuel fragment size on release of cesium was investigated over 10 h at a temperature of 1300–1400 °C for fuel fragments with an O/U ratio of 2.2. Re-fragmentation of the original fragments was observed as changes in cesium release count rates as fuel was heated from 484 to 1329 °C. The release of cesium is highly dependent on the size of fuel fragments and most of the cesium is released as the temperature is held at the maximum target value. 相似文献
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Diverse harmful compounds can be emitted during the heating of tobacco sticks for heated tobacco products (HTPs). In this study, the generation of harmful compounds from the filter, instead of tobacco in tobacco sticks, was confirmed. The heat of a heated tobacco product device can be transferred to the tobacco stick filter, resulting in the generation of harmful compounds from the heated filter. Since the heating materials (tobacco consumable) of the tobacco sticks evaluated in this study were different depending on the brand, the harmful compounds emitted from the heated tobacco stick filters were examined by focusing on the carbonyl compounds, using three different tobacco stick parts. Acetaldehyde and propionaldehyde exhibited the highest concentrations in HTP aerosols produced by heating the tobacco consumable (conventional case) (63.5 ± 18.4 µg/stick and 1.71 ± 0.123 µg/stick, respectively). The aerosols produced by heating tobacco stick filters had higher formaldehyde and acrolein concentrations (0.945 ± 0.214 µg/stick and 0.519 ± 0.379 µg/stick) than the aerosols generated from heated tobacco consumable (0.641 ± 0.092 µg/stick and 0.220 ± 0.102 µg/stick). As such, formaldehyde and acrolein were produced by heating small parts of the mouthpiece of a tobacco stick, regardless of the heated tobacco product brand. In addition, acetone was only detected in the aerosols generated from heated filters (0.580 ± 0.305 µg/stick). Thus, safety evaluations of heated tobacco products should include considerations of the harmful compounds generated by heating tobacco stick mouthpieces for heated tobacco products in addition to those found in heated tobacco product aerosols. 相似文献
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Kento Kimura Joh Motomatsu Yoichi Tominaga 《Journal of Polymer Science.Polymer Physics》2016,54(23):2442-2447
Solid polymer electrolytes (SPEs) are compounds of great interest as safe and flexible alternative ionics materials, particularly suitable for energy storage devices. We study an unusual dependence on the salt concentration of the ionic conductivity in an SPE system based on poly(ethylene carbonate) (PEC). Dielectric relaxation spectroscopy reveals that the ionic conductivity of PEC/lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) electrolyte continues to increase with increasing salt concentration because the segmental motion of the polymer chains is enhanced by the plasticizing effect of the imide anion. Fourier transfer‐infrared (FTIR) spectroscopy suggests that this unusual phenomenon arises because of a relatively loose coordination structure having moderately aggregated ions, in contrast to polyether‐based systems. Comparative FTIR study against PEC/lithium perchlorate (LiClO4) electrolytes suggests that weak ionic interaction between Li and TFSI ions is also important. Highly concentrated electrolytes with both reasonable conductivity and high lithium transference number (t+) can be obtained in the PEC/LiTFSI system as a result of the unusual salt concentration dependence of the conductivity and the ionic solvation structure. The resulting concentrated PEC/LiTFSI electrolytes have extraordinary oxidation stability and prevent any Al corrosion reaction in a cyclic voltammetry. These are inherent effects of the highly concentrated salt. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2442–2447 相似文献
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Proteomic profiling of human hippocampus 总被引：4，自引：0，他引：4