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11.
Jie Liu Xiaohui Li Jiangjiang Feng Chuang Zheng Yamin Wang Aocheng Wang Xinfeng Liu 《Annalen der Physik》2020,532(3):1900454
Zinc sulfide (ZnS), which belongs to transition metal monochalcogenides, is a semiconductor material with wide direct band gap. It can potentially show some special applications (such as luminescence, phosphor, sensors, infrared window materials, photocatalysis) by changing the morphology, size, and crystal structure of semiconductor materials. However, ZnS nanospheres have not been studied as optical modulators until now. Herein, ZnS nanospheres are synthesized by the hydrothermal method and are used to realize optical modulators in an Er-doped fiber laser. The evanescent field effect is utilized to incorporate the ZnS nanospheres on a tapered fiber. Furthermore, with the increase in pump power, the modulation interval gradually decreases to a minimum of 34.36 ns corresponding to the modulation frequency of 29.1 MHz, which is the highest modulation frequency to our knowledge in a ring cavity all-fiber laser. These results demonstrate ZnS nanospheres together with the interaction of dispersion and nonlinearity in optical fibers can modulate the proposed lasers. This not only provides a new method for controlling the power and frequency of all optical modulators, but also marks an important step for ZnS materials in optics research and device applications. 相似文献
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M.A. Salam M.A. Affan Fasihuddin B. Ahmad I. Jusoh Mustaffa B. Shamsuddin Bohari Yamin Yang Farina 《Journal of organometallic chemistry》2012,696(26):4202-4206
A new trinuclear di-n-butyltin(IV) complex with pyruvic acid-N(4)-cyclohexylthiosemicarbazone (H2PACT) ligand was synthesized and characterized by elemental analyses, molar conductivity, UV–Vis, FT-IR, 1H, 119Sn NMR spectroscopy and single crystal X-ray study. Single crystal X-ray diffraction data revealed that this complex was trinuclear cyclic fashion with the pyruvic acid-N(4)-cyclohexylthiosemicarbazone ligand. In the trinuclear di-n-butyltin(IV) complex, the ligand (H2PACT) is coordinated to the central tin(IV) atoms via the carboxylato-O, the azomethine-N and the thiolato-S atoms. The trinuclear tin system is formed by the bridges through the carbonyl oxygen atom of the carboxylate moieties and making the tin atom of seven coordinated in distorted pentagonal bipyramidal geometry. Single crystal X-ray data indicates that the complex (1) crystallized in cubic system with space group I-43d, a = b = c = 30.3273(17) Å, α = β = γ = 90°, Z = 16, μ(MoKα) = 1.209 mm?1, F(000) = 12,144, and final R1 = 0.0390, wR2 = 0.0843 for observed reflections 4582(I > 2σ(I)). 相似文献
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Annals of Global Analysis and Geometry - In this paper, we propose a heat flow for the critical Trudinger-Moser functional on a closed Riemann surface $$(\Sigma ,g)$$ . We prove its short time... 相似文献
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Yamin Feng Jinghua Chen Xintang Huang Weifeng Liu Yu Zhu Wei Qin Xiaoyuan Mo 《Crystal Research and Technology》2016,51(10):548-553
A dye‐sensitized solar cell (DSSC) based on ZnO/TiO2 composite nanorods (NRs) photoanode is fabricated. The power conversion efficiency (PCE) of the ZnO/TiO2 composite NRs film DSSC is 4.36%, which is obviously higher than that of DSSCs based on pure TiO2 NRs (0.6%) and ZnO NRs (3.10%). The enhanced performance of ZnO/TiO2 composite NRs film DSSC can be attributed to the combined effects of ZnO and TiO2 NRs. In this architecture, the thick ZnO NRs overlayer offers a large surface area for enough dye absorption, while the thin TiO2 NRs underlayer not only offers a direct and quick pathway for photoinjected electron transfer along the photoanode but also acts as a blocking layer, which effectively hinders the direct contact between the substrate and the electrolyte resulting in lower carrier recombination. 相似文献
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M. Šiljegovi? Z.M. Ka?arevi?-Popovi? N. Bibi? Z.M. Jovanovi? S. Maleti? M. Stchakovsky A.N. Krklješ 《Radiation Physics and Chemistry》2011,80(12):1378-1385
Fluorinated ethylene propylene (FEP) and tetrafluoroethylene–perfluoro(alkoxy vinyl ether) (PFA) copolymer films were irradiated in vacuum with 60 keV C4+ and N4+ ions to fluences ranging from 1.0×1012 to 5.0×1015 cm−2. Changes in optical and dielectric properties were analyzed by spectroscopic ellipsometry and ultraviolet–visible (UV–vis), Raman and dielectric relaxation spectroscopies. Direct and indirect energy band gap values were determined from the absorption edge in the 200–800 nm region using Tauc's relation. The values of the direct energy gap have been found to be greater than the corresponding values of the indirect energy gap. Significant changes in the index of refraction, and β and γ dielectric relaxations were observed in the case of N4+ irradiated FEP and PFA samples. 相似文献
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The chemical grafting of thiol terminated poly(sodium styrenesulfonate)(HS-PSSS) chains from sodium nitrate (NaNO_3) salt solution to a gold surface was investigated with a quartz crystal microbalance with dissipation monitoring (QCM-D) in different salt concentrations.It was found that at low salt concentration grafting density of HS-PSSS was low and the grafted chains adopted a mushroom conformation.With the increase of salt concentration polyelectrolyte chains underwent a transition toward coiled stat... 相似文献
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Yi L Zhang P Ji X Liang Y Wang Y Zhou Z Chen B 《Chemical & pharmaceutical bulletin》2011,59(7):839-843
The article reports a simple, sensitive and fast LC/MS method for the analysis of L-arginine (L-Arg), asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) in human plasma. The homoarginine was used as the internal standard (IS). The chromatographic separation was achieved on C??(150 mm×2.1 mm, 5 μm) column with a mobile phase consisting of ammonium acetate (0.25 mmol/l) and methanol (93 : 7, v/v), at a flow rate of 0.2 ml/min. L-Arg, ADMA and SDMA were well separated by LC/MS with selective ion mode (SIM). The method was successfully applied to type 2 diabetes mellitus (T2DM) study. Twenty-one healthy controls and twenty-two T2DM patients before and after treatment two years were investigated. The results indicated that the level of ADMA in T2DM was significantly higher than that in healthy controls. Furthermore, ADMA has important association with the development of cardiovascular diseases. 相似文献