Wavelength conversion based on the cross-gain modulation (XGM) in a traveling-wave type semiconductor optical amplifier (TW-SOA) using assist light is theoretically studied. Taking into account the spatial and tempora...Wavelength conversion based on the cross-gain modulation (XGM) in a traveling-wave type semiconductor optical amplifier (TW-SOA) using assist light is theoretically studied. Taking into account the spatial and temporal variations of carrier density along the SOA length, the dependency of the conversion response on the assist light conditions is simulated both for co- and counter-propagating assist light schemes.展开更多
We analyzed the characteristics of cross-modulations (XM) and their recovery times in a semiconductor optical amplifier by a newly-developed TMM. The calculated results suggest faster recovery of the XMs by introducin...We analyzed the characteristics of cross-modulations (XM) and their recovery times in a semiconductor optical amplifier by a newly-developed TMM. The calculated results suggest faster recovery of the XMs by introducing a high-power assist light.展开更多
Bi（0.76）Sb（1.24）S3 nanocrystals were synthesized by a rapid microwave-assisted hydrothermal method using bismuth nitrate, antimony pentoxide and thioacetamide as starting materials and characterized by X-ray diffr...Bi（0.76）Sb（1.24）S3 nanocrystals were synthesized by a rapid microwave-assisted hydrothermal method using bismuth nitrate, antimony pentoxide and thioacetamide as starting materials and characterized by X-ray diffraction（XRD）, scanning electron microscopy（SEM） and UV-vis diffuse reflectance spectroscopy（DRS）. The effects of the synthetic condition on the product composition were investigated. The photocatalytic activities of Bi（0.76）Sb（1.24）S3 nanocrystals for the degradation of methyl orange and p-hydroxyazobenzene under visible light irradiation were evaluated. Bi（0.76）Sb（1.24）S3 exhibited good and stable visible light photocatalytic activity.展开更多
ZnO as a semiconductor photocatalyst is widely applied in the photodegradation of organic pollutants. Its photocatalytic activity is greatly decreased because of the recombination of photoexcited electrons and holes i...ZnO as a semiconductor photocatalyst is widely applied in the photodegradation of organic pollutants. Its photocatalytic activity is greatly decreased because of the recombination of photoexcited electrons and holes in the bulk. In this work, ZnO sheets are synthesized by adjusting the NaOH concentration under light irradiation at room temperature. Compared with ZnO particles, the ZnO sheets prepared with a light-assisted growth method exhibit a higher rate of photodegradation of methylene blue under UV visible light irradiation. The improved photodegradation rate is mainly attributed to the shortened transport distance of photoexcited electrons, the high surface area, and the surface atom structure modified by the light-assisted growth process. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.展开更多
The uniformity of the colour in leathers for the furnishing and <i>automotive</i> sectors is a particularly important feature, especially for white or light-coloured </span></span&g...The uniformity of the colour in leathers for the furnishing and <i>automotive</i> sectors is a particularly important feature, especially for white or light-coloured </span></span><span style="white-space:normal;"><span style="font-family:"">articles, intended to the high-end market;on these articles any colour alteration can be very visible and unpleasant, with possible technical and economic consequences for the producers. In a previous study, we analysed the possible causes behind the formation of some peculiar pink/salmon stains on different kinds of white/beige/light-coloured leather furnishing items, where we focalized our attention on TiO<sub>2</sub> properties and its possible interaction with some organic-based antioxidants. In recent years, due to many other similar cases of defects </span></span><span style="white-space:normal;"><span style="font-family:"">that </span></span><span style="white-space:normal;"><span style="font-family:"">occurred to tanners and to upholstery traders, we decided to enhance the investigations concerning this topic. More in detail we analysed, defective leathers, powder pigments and chemicals, in order to identify the possible role of some substances in this issue, with particular reference to some antioxidants and aluminosilicates, where several diagnostic techniques have been utilised, as ATR-IR (Attenuated Total Reflectance IR Spectroscopy), SEM-EDX (Scanning Electron Microscopy</span></span><span style="white-space:normal;"><span style="font-family:"">-</span></span><span style="white-space:normal;"><span style="font-family:"">Energy Dispersive X-ray Analysis), XRF (X-ray Fluorescence spectrometry)</span></span><span style="white-space:normal;"><span style="font-family:"">,</span></span><span style="white-space:normal;"><span style="font-family:""> GC-MS (Gas Chromatography-Mass Spectrometry), and DSC/TGA (Differential scanning calorimetry/Thermogravimetry) equipment.展开更多
以六次甲基四胺(HMTA)和聚乙烯吡咯烷酮(PVP)为混合辅助剂,采用沉淀法合成了立方晶相棱形十二面体Ag3PO4微晶,对其进行了表征,并通过降解罗丹明B考察了其可见光催化活性。实验结果表明:以0.10g(25 g/mol(以Ag NO3计))HMTA和0.10 g PVP...以六次甲基四胺(HMTA)和聚乙烯吡咯烷酮(PVP)为混合辅助剂,采用沉淀法合成了立方晶相棱形十二面体Ag3PO4微晶,对其进行了表征,并通过降解罗丹明B考察了其可见光催化活性。实验结果表明:以0.10g(25 g/mol(以Ag NO3计))HMTA和0.10 g PVP为混合辅助剂合成的棱形十二面体Ag3PO4微晶,其禁带宽度为2.17e V,对罗丹明B有较好的可见光催化活性;在8 mg/L罗丹明B溶液中加入0.4 g/L Ag3PO4,可见光照射12 min时,未添加辅助剂以及分别添加0.10 g PVP、0.10 g HMTA、0.10 g HMTA和0.10 g PVP混合辅助剂制备的Ag3PO4对罗丹明B的降解率分别为67.59%,76.25%,91.88%,99.64%;棱形十二面体Ag3PO4微晶重复使用4次后,罗丹明B的降解率仍达91.59%,说明该光催化剂具有较好的重复使用性能。展开更多
文摘Wavelength conversion based on the cross-gain modulation (XGM) in a traveling-wave type semiconductor optical amplifier (TW-SOA) using assist light is theoretically studied. Taking into account the spatial and temporal variations of carrier density along the SOA length, the dependency of the conversion response on the assist light conditions is simulated both for co- and counter-propagating assist light schemes.
文摘We analyzed the characteristics of cross-modulations (XM) and their recovery times in a semiconductor optical amplifier by a newly-developed TMM. The calculated results suggest faster recovery of the XMs by introducing a high-power assist light.
基金supported by the National Natural Science Foundation of China(21307012)Educational Commission of Fujian Province(JK2013007,2014J01035,JA15138)
文摘Bi（0.76）Sb（1.24）S3 nanocrystals were synthesized by a rapid microwave-assisted hydrothermal method using bismuth nitrate, antimony pentoxide and thioacetamide as starting materials and characterized by X-ray diffraction（XRD）, scanning electron microscopy（SEM） and UV-vis diffuse reflectance spectroscopy（DRS）. The effects of the synthetic condition on the product composition were investigated. The photocatalytic activities of Bi（0.76）Sb（1.24）S3 nanocrystals for the degradation of methyl orange and p-hydroxyazobenzene under visible light irradiation were evaluated. Bi（0.76）Sb（1.24）S3 exhibited good and stable visible light photocatalytic activity.
基金support from the Institute of Metal Research,Chinese Academy of Sciencessupported by the National Science Fund of China(51202105,21366020)+1 种基金the Natural Science Foundation of Jiangxi Province(20151BAB216006)the Science and Technology Project of Education Department of Jiangxi Province(GJJ14109)
文摘ZnO as a semiconductor photocatalyst is widely applied in the photodegradation of organic pollutants. Its photocatalytic activity is greatly decreased because of the recombination of photoexcited electrons and holes in the bulk. In this work, ZnO sheets are synthesized by adjusting the NaOH concentration under light irradiation at room temperature. Compared with ZnO particles, the ZnO sheets prepared with a light-assisted growth method exhibit a higher rate of photodegradation of methylene blue under UV visible light irradiation. The improved photodegradation rate is mainly attributed to the shortened transport distance of photoexcited electrons, the high surface area, and the surface atom structure modified by the light-assisted growth process. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.
文摘The uniformity of the colour in leathers for the furnishing and <i>automotive</i> sectors is a particularly important feature, especially for white or light-coloured </span></span><span style="white-space:normal;"><span style="font-family:"">articles, intended to the high-end market;on these articles any colour alteration can be very visible and unpleasant, with possible technical and economic consequences for the producers. In a previous study, we analysed the possible causes behind the formation of some peculiar pink/salmon stains on different kinds of white/beige/light-coloured leather furnishing items, where we focalized our attention on TiO<sub>2</sub> properties and its possible interaction with some organic-based antioxidants. In recent years, due to many other similar cases of defects </span></span><span style="white-space:normal;"><span style="font-family:"">that </span></span><span style="white-space:normal;"><span style="font-family:"">occurred to tanners and to upholstery traders, we decided to enhance the investigations concerning this topic. More in detail we analysed, defective leathers, powder pigments and chemicals, in order to identify the possible role of some substances in this issue, with particular reference to some antioxidants and aluminosilicates, where several diagnostic techniques have been utilised, as ATR-IR (Attenuated Total Reflectance IR Spectroscopy), SEM-EDX (Scanning Electron Microscopy</span></span><span style="white-space:normal;"><span style="font-family:"">-</span></span><span style="white-space:normal;"><span style="font-family:"">Energy Dispersive X-ray Analysis), XRF (X-ray Fluorescence spectrometry)</span></span><span style="white-space:normal;"><span style="font-family:"">,</span></span><span style="white-space:normal;"><span style="font-family:""> GC-MS (Gas Chromatography-Mass Spectrometry), and DSC/TGA (Differential scanning calorimetry/Thermogravimetry) equipment.
文摘以六次甲基四胺(HMTA)和聚乙烯吡咯烷酮(PVP)为混合辅助剂,采用沉淀法合成了立方晶相棱形十二面体Ag3PO4微晶,对其进行了表征,并通过降解罗丹明B考察了其可见光催化活性。实验结果表明:以0.10g(25 g/mol(以Ag NO3计))HMTA和0.10 g PVP为混合辅助剂合成的棱形十二面体Ag3PO4微晶,其禁带宽度为2.17e V,对罗丹明B有较好的可见光催化活性;在8 mg/L罗丹明B溶液中加入0.4 g/L Ag3PO4,可见光照射12 min时,未添加辅助剂以及分别添加0.10 g PVP、0.10 g HMTA、0.10 g HMTA和0.10 g PVP混合辅助剂制备的Ag3PO4对罗丹明B的降解率分别为67.59%,76.25%,91.88%,99.64%;棱形十二面体Ag3PO4微晶重复使用4次后,罗丹明B的降解率仍达91.59%,说明该光催化剂具有较好的重复使用性能。
