We report comparatively on fabrication of two-section ridge-waveguide tapered 3 quantum well (QW) InGaAsP/InP (1300 nm) and 5 QW AlGaInAs/InP (1550 nm) diode lasers. Gas mixtures of CCl2F2/O2 and H2/CH4 were used to f...We report comparatively on fabrication of two-section ridge-waveguide tapered 3 quantum well (QW) InGaAsP/InP (1300 nm) and 5 QW AlGaInAs/InP (1550 nm) diode lasers. Gas mixtures of CCl2F2/O2 and H2/CH4 were used to form ridge-waveguide on the lasers with InP-based material structures. As known, chlorine- and hydro-carbon based gases are used to fabricate ridge-waveguide structures. Here, we show the difference between the structures obtained by using the both gas mixtures in which surface and sidewall structures as well as performance of the lasers were analysed using scanning electron microscopy. It is demonstrated that gas mixtures of CCl2F2/O2 highly deteriorated the etched structures although different flow rates, rf powers and base pressures were tried. We also show that the structures etched with H2/CH4 gas mixtures produced much better results that led to the successful fabrication of two-section devices with ridge-waveguide. The lasers fabricated using H2/CH4 were characterized using output power-current (P-I) and spectral results.展开更多
A microporous and robust bimetal-organic framework[Cd_(2)Ba(NH_(2)-BTB)_(2)]·2(DMA)·2(H_(2)O)(1)was constructed by mixing the heterometallic nodes and an tridentate carboxyl ligand with amino group,benefitin...A microporous and robust bimetal-organic framework[Cd_(2)Ba(NH_(2)-BTB)_(2)]·2(DMA)·2(H_(2)O)(1)was constructed by mixing the heterometallic nodes and an tridentate carboxyl ligand with amino group,benefiting from the synergistic effect of active sites,exposed amino groups and ultramicroporous structure.This compound displays an extraordinary selectivity of CO_(2)/CH4 and C_(2)H_(2)/CH_(4)(16.7 and 146.3)at 298 K and 1 atm,which can exceed those of many reported MOFs under the same conditions.This work provides an important model to design metal-organic frameworks for the adsorption and separation of small gas molecules.展开更多
Monte Carlo simulations are adopted to study the electron motion in the mixture of H2 and CH4 during diamond synthesis via Glow Plasma-assisted Chemical Vapor Deposition (GPCVD). The non-uniform electric field is used...Monte Carlo simulations are adopted to study the electron motion in the mixture of H2 and CH4 during diamond synthesis via Glow Plasma-assisted Chemical Vapor Deposition (GPCVD). The non-uniform electric field is used and the avalanche of electrons is taken into account in this simulation. The average energy distribution of electrons and the space distribution of effective species such as CH3, CH+3, CH+ and H at various gas pressures are given in this paper, and optimum experimental conditions are inferred from these results.展开更多
A lot of liquid-gas and liquid-gas-solid inclusions were found in Pharkant jadeitites, northwestern Myanmar and their characteristics, geological setting and porphyroclastic jadeites with inclusions in them were descr...A lot of liquid-gas and liquid-gas-solid inclusions were found in Pharkant jadeitites, northwestern Myanmar and their characteristics, geological setting and porphyroclastic jadeites with inclusions in them were described in detail. The results analyzed by Raman spectrometer showed that the component of liquid-gas phase and solid phase (daughter minerals) in fluid inclusions is H2O + CH4 and jadeite separately. The results indicated that Pharkant jadeitites were crystallized from H2O + CH4 bearing jadeitic melt which may originate from mantle. The P-T conditions in which the jadeitites were crystallized were speculated to be T】650℃, P】1.5 GPa.展开更多
Acetylene purification from methane is challenging in the field of porous organic polymers(POPs).Herein,we have provided one-pot Ullmann coupling reaction to synthesize a series of POPs with rich N-sites,named FJU-POP...Acetylene purification from methane is challenging in the field of porous organic polymers(POPs).Herein,we have provided one-pot Ullmann coupling reaction to synthesize a series of POPs with rich N-sites,named FJU-POP-n,wherein the low-cost and non-toxic Cu(acac)2 and environmental-friendly glycerol are employed as catalyst and solvent,respectively.展开更多
基金the financial support of TUB-ITAK via Project 107E163.
文摘We report comparatively on fabrication of two-section ridge-waveguide tapered 3 quantum well (QW) InGaAsP/InP (1300 nm) and 5 QW AlGaInAs/InP (1550 nm) diode lasers. Gas mixtures of CCl2F2/O2 and H2/CH4 were used to form ridge-waveguide on the lasers with InP-based material structures. As known, chlorine- and hydro-carbon based gases are used to fabricate ridge-waveguide structures. Here, we show the difference between the structures obtained by using the both gas mixtures in which surface and sidewall structures as well as performance of the lasers were analysed using scanning electron microscopy. It is demonstrated that gas mixtures of CCl2F2/O2 highly deteriorated the etched structures although different flow rates, rf powers and base pressures were tried. We also show that the structures etched with H2/CH4 gas mixtures produced much better results that led to the successful fabrication of two-section devices with ridge-waveguide. The lasers fabricated using H2/CH4 were characterized using output power-current (P-I) and spectral results.
基金supported financially by National Natural Science Foundation of China (No. U1904183)Science Foundation for Excellent Youth Scholars of Henan (212300410061, 20HASTIT006)
文摘A microporous and robust bimetal-organic framework[Cd_(2)Ba(NH_(2)-BTB)_(2)]·2(DMA)·2(H_(2)O)(1)was constructed by mixing the heterometallic nodes and an tridentate carboxyl ligand with amino group,benefiting from the synergistic effect of active sites,exposed amino groups and ultramicroporous structure.This compound displays an extraordinary selectivity of CO_(2)/CH4 and C_(2)H_(2)/CH_(4)(16.7 and 146.3)at 298 K and 1 atm,which can exceed those of many reported MOFs under the same conditions.This work provides an important model to design metal-organic frameworks for the adsorption and separation of small gas molecules.
基金This work was supported by Doctor Foundation of Hebei Education Committee Hebei Natural Science Foundation(599091 ) of China
文摘Monte Carlo simulations are adopted to study the electron motion in the mixture of H2 and CH4 during diamond synthesis via Glow Plasma-assisted Chemical Vapor Deposition (GPCVD). The non-uniform electric field is used and the avalanche of electrons is taken into account in this simulation. The average energy distribution of electrons and the space distribution of effective species such as CH3, CH+3, CH+ and H at various gas pressures are given in this paper, and optimum experimental conditions are inferred from these results.
文摘A lot of liquid-gas and liquid-gas-solid inclusions were found in Pharkant jadeitites, northwestern Myanmar and their characteristics, geological setting and porphyroclastic jadeites with inclusions in them were described in detail. The results analyzed by Raman spectrometer showed that the component of liquid-gas phase and solid phase (daughter minerals) in fluid inclusions is H2O + CH4 and jadeite separately. The results indicated that Pharkant jadeitites were crystallized from H2O + CH4 bearing jadeitic melt which may originate from mantle. The P-T conditions in which the jadeitites were crystallized were speculated to be T】650℃, P】1.5 GPa.
基金This work was financially supported by the National Natural Science Foundation of China(grant nos.21975044,21971038 and 219722810)Fujian Provincial Department of Science and Technology(2018J07001,2019L3004,2019H6012 and 2021H0062).
文摘Acetylene purification from methane is challenging in the field of porous organic polymers(POPs).Herein,we have provided one-pot Ullmann coupling reaction to synthesize a series of POPs with rich N-sites,named FJU-POP-n,wherein the low-cost and non-toxic Cu(acac)2 and environmental-friendly glycerol are employed as catalyst and solvent,respectively.