We fabricate the Tm-doped double cladding silica fiber by using the vapor-solution hybrid-doping method, then build up an all-fiber Tin-doped fiber laser which can provide the output power of up to 121 W, correspondin...We fabricate the Tm-doped double cladding silica fiber by using the vapor-solution hybrid-doping method, then build up an all-fiber Tin-doped fiber laser which can provide the output power of up to 121 W, corresponding to a slope efficiency of 51% and an optical-optical efficiency of 48%. By using the domestic Tin-doped fiber, it is the first time a hundred-watt level output at 1915nm has been achieved, to the best of our knowledge. The thermal effect of Tm-doped fiber laser is also analyzed.展开更多
We report on the room-temperature cascade laser （QCL） at λ -4.7μm. cw operation of a surface grating Both grating design and material distributed feedback （DFB） quantum optimization are used to decrease the thre...We report on the room-temperature cascade laser （QCL） at λ -4.7μm. cw operation of a surface grating Both grating design and material distributed feedback （DFB） quantum optimization are used to decrease the threshold current density and to increase the output power. For a high-reflectivity-coated 13-μm-wide and 4- mm-long laser, high wall-plug efficiency of 6% is obtained at 20℃ from a single facet producing over I W of ew output power. The threshold current density of DFB QCL is as low as 1.13kA/cm^2 at 10℃ and 1.34kA/cm2 at 30℃ in cw mode. Stable single-mode emission with a side-mode suppression ratio of about 30 dB is observed in tile working temperature range of 20-50℃.展开更多
In order to solve the disadvantages caused by mechanical slide rheostat that has big errors and low precision,a novel voltage regulation method for high voltage DC power supply was introduced.The key of this method we...In order to solve the disadvantages caused by mechanical slide rheostat that has big errors and low precision,a novel voltage regulation method for high voltage DC power supply was introduced.The key of this method were digital potentiometer MAXIM 5455 and linear photoelectric coupling LOC110,and application programs were compiled using Visual Basic which was graphical compiling language,furthermore the communication between exterior and computer was carried out by ICP7044D module,in consequence the output value of high voltage DC power supply could be regulated with computer.The measured results showed that this method could accurately,conveniently and rapidly regulate the output value of high voltage DC power supply.展开更多
A novel low power and low voltage current mirror with a very low current copy error is presented and the principle of its operation is discussed. In this circuit, the gain boosting regulated cascode scheme is used to ...A novel low power and low voltage current mirror with a very low current copy error is presented and the principle of its operation is discussed. In this circuit, the gain boosting regulated cascode scheme is used to improve the output resistance, while using inverter as an amplifier. The simulation results with HSPICE in TSMC 0.18 μm CMOS technology are given, which verify the high performance of the proposed structure. Simulation results show an input resistance of 0.014 Ω and an output resistance of 3 GΩ. The current copy error is favorable as low as 0.002% together with an input （the minimum input voltage of Vin,min- 0.24 V） and an output （the minimum output voltage of Vout,min~ 0.16 V） compliances while working with the 1 V power supply and the 50 μA input current. The current copy error is near zero at the input current of 27 μA. It consumes only 76μW and introduces a very low output offset current of 50 pA.展开更多
In this study,conductive polymer polyaniline(PANI)is employed to modify the anodes of benthic microbial fuel cells(BMFC).Four electrochemical methods are used to synthesize the polyaniline anodes;the results show that...In this study,conductive polymer polyaniline(PANI)is employed to modify the anodes of benthic microbial fuel cells(BMFC).Four electrochemical methods are used to synthesize the polyaniline anodes;the results show that the PANI modification,especially the pulse potential method for PANI synthesis could obviously improve the cell energy output and reduce the anode internal resistance.The anode is modified by PANI doped with Fe or Mn to further improve the BMFC performance.A maximum power density of 17.51 mW/m2 is obtained by PANI-Fe anode BMFC,which is 8.1 times higher than that of control.The PANI-Mn anode BMFC also gives a favorable maximum power density(16.78 mW/m2).Fe or Mn modification has better effect in improving the conductivity of polyaniline,thus improving the energy output of BMFCs.This work applying PANI composite anode into BMFC brings new development prospect and could promote the practical application of BMFC.展开更多
基金Supported by the National High-Technology Research and Development Program of China under Grant No 2013AA031501the National Natural Science Foundation of China for Director Fund of WNLO
文摘We fabricate the Tm-doped double cladding silica fiber by using the vapor-solution hybrid-doping method, then build up an all-fiber Tin-doped fiber laser which can provide the output power of up to 121 W, corresponding to a slope efficiency of 51% and an optical-optical efficiency of 48%. By using the domestic Tin-doped fiber, it is the first time a hundred-watt level output at 1915nm has been achieved, to the best of our knowledge. The thermal effect of Tm-doped fiber laser is also analyzed.
基金Supported by the National Basic Research Program of China under Grant Nos 2013CB632801 and 2013CB632803the National Natural Science Foundation of China under Grant Nos 61435014,61306058 and 61274094the Beijing Natural Science Foundation under Grant No 4144086
文摘We report on the room-temperature cascade laser （QCL） at λ -4.7μm. cw operation of a surface grating Both grating design and material distributed feedback （DFB） quantum optimization are used to decrease the threshold current density and to increase the output power. For a high-reflectivity-coated 13-μm-wide and 4- mm-long laser, high wall-plug efficiency of 6% is obtained at 20℃ from a single facet producing over I W of ew output power. The threshold current density of DFB QCL is as low as 1.13kA/cm^2 at 10℃ and 1.34kA/cm2 at 30℃ in cw mode. Stable single-mode emission with a side-mode suppression ratio of about 30 dB is observed in tile working temperature range of 20-50℃.
基金Supported by National Natural Science Foundation of China（60774010 10971256） Natural Science Foundation of Jiangsu Province（BK2009083）+1 种基金 Program for Fundamental Research of Natural Sciences in Universities of Jiangsu Province（07KJB510114） Shandong Provincial Natural Science Foundation of China（ZR2009GM008 ZR2009AL014）
基金Project Supported by National Natural Science Foundation of China（50637020）.
文摘In order to solve the disadvantages caused by mechanical slide rheostat that has big errors and low precision,a novel voltage regulation method for high voltage DC power supply was introduced.The key of this method were digital potentiometer MAXIM 5455 and linear photoelectric coupling LOC110,and application programs were compiled using Visual Basic which was graphical compiling language,furthermore the communication between exterior and computer was carried out by ICP7044D module,in consequence the output value of high voltage DC power supply could be regulated with computer.The measured results showed that this method could accurately,conveniently and rapidly regulate the output value of high voltage DC power supply.
基金supported by the Iran University of Science and Technology
文摘A novel low power and low voltage current mirror with a very low current copy error is presented and the principle of its operation is discussed. In this circuit, the gain boosting regulated cascode scheme is used to improve the output resistance, while using inverter as an amplifier. The simulation results with HSPICE in TSMC 0.18 μm CMOS technology are given, which verify the high performance of the proposed structure. Simulation results show an input resistance of 0.014 Ω and an output resistance of 3 GΩ. The current copy error is favorable as low as 0.002% together with an input （the minimum input voltage of Vin,min- 0.24 V） and an output （the minimum output voltage of Vout,min~ 0.16 V） compliances while working with the 1 V power supply and the 50 μA input current. The current copy error is near zero at the input current of 27 μA. It consumes only 76μW and introduces a very low output offset current of 50 pA.
基金Project(HIT.NSRIF.2014128)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(2014M551257)supported by the China Postdoctoral Science FoundationProject(WH20150208)supported by the Subject Development Foundation of Harbin Institute of Technology at Weihai,China
文摘In this study,conductive polymer polyaniline(PANI)is employed to modify the anodes of benthic microbial fuel cells(BMFC).Four electrochemical methods are used to synthesize the polyaniline anodes;the results show that the PANI modification,especially the pulse potential method for PANI synthesis could obviously improve the cell energy output and reduce the anode internal resistance.The anode is modified by PANI doped with Fe or Mn to further improve the BMFC performance.A maximum power density of 17.51 mW/m2 is obtained by PANI-Fe anode BMFC,which is 8.1 times higher than that of control.The PANI-Mn anode BMFC also gives a favorable maximum power density(16.78 mW/m2).Fe or Mn modification has better effect in improving the conductivity of polyaniline,thus improving the energy output of BMFCs.This work applying PANI composite anode into BMFC brings new development prospect and could promote the practical application of BMFC.
