从抛光液组分配比、温度、阳极电流密度以及阴阳极材料、保养周期和保养方法 6个方面对0.07 mm厚的超薄不锈钢材料连续电解抛光工艺进行了优化,得到最佳抛光液配方为:浓磷酸700 m L/L,浓硫酸250 m L/L,复合添加剂(含40 m L/L明胶和7.5 m...从抛光液组分配比、温度、阳极电流密度以及阴阳极材料、保养周期和保养方法 6个方面对0.07 mm厚的超薄不锈钢材料连续电解抛光工艺进行了优化,得到最佳抛光液配方为:浓磷酸700 m L/L,浓硫酸250 m L/L,复合添加剂(含40 m L/L明胶和7.5 mL/L甘油的异丙醇溶液)50 mL/L。最佳操作条件为:阳极电流密度18~50 A/dm^2,温度60~80°C,时间2~3 min,阴阳极间距50 mm,以钛制作的阴极板、辅助阳极导电块、导电轮和导电轮固定杆的保养周期分别为3、48、1 440和3 h。给出了生产过程中常见故障的排除方法。该工艺对超薄不锈钢零件边缘裁切面毛刺及表面的抛光效果完全满足产品质量要求。展开更多
为进一步提高有机废水的厌氧处理效率,同时实现能源物质的回收,采用微生物电解池并结合连续流工艺处理有机废水并同步回收甲烷,系统地研究不同水力停留时间、有机负荷、外加电压对微生物电解池内基质浓度的降解、甲烷生产速率等方面的影...为进一步提高有机废水的厌氧处理效率,同时实现能源物质的回收,采用微生物电解池并结合连续流工艺处理有机废水并同步回收甲烷,系统地研究不同水力停留时间、有机负荷、外加电压对微生物电解池内基质浓度的降解、甲烷生产速率等方面的影响.结果表明,在同一有机负荷下,随着外加电压(0.6 V,1.0 V,1.2 V)的升高,微生物电解池COD的去除效率和甲烷生产率也同时提高.在进水COD浓度为1 178 mg L-1、水力停留时间为8 h、外加电压为1.2V的条件下,其COD去除率、甲烷浓度、甲烷产生速率分别为97.7%、96%、1 071 m L L-1 d-1,较普通厌氧发酵(对照组)分别提高了31.5%、13.6%、123%;当进水COD浓度为4 812 mg L-1、水力停留时间为20 h、外加电压为1.2 V时,甲烷的产生速率达1 888 m L L-1 d-1,达理论产率的98.0%,而此条件下对照组甲烷产生速率仅为理论值的64.9%.说明连续流微生物电解池能够明显提高有机废水的处理效率,并实现处理过程中稳定回收甲烷的目的.高通量分析结果显示:微生物电解池阳极碳毡优势菌群为methanogens与Geobacter sp.,其丰度分别占总菌群的53.3%和7.5%,而对照组碳毡相应丰度仅为25.2%和0.7%.此外,研究发现有机负荷与电解池能量的消耗呈负相关,当外加电压为0.6 V时,有机负荷由3.5 kg m-3d-1提升至5.7 kg m-3d-1时,电解池能量消耗降低了79.3%.据此认为,通过优化水力停留时间和外加电压来处理有机废水并同步生产甲烷是可行的.展开更多
The portrayal of obscenity in television series is not a new issue in our society. It is a reasonable fact to be understood, that the exposure to such explicit content of obscenity is acceptable in Western culture but...The portrayal of obscenity in television series is not a new issue in our society. It is a reasonable fact to be understood, that the exposure to such explicit content of obscenity is acceptable in Western culture but somehow or rather, the acceptance of obscenity among the Asian society is still taboo and this has geared parents to pay greater attention to what type of media content should be watched by their children. The researcher believes the audience could also educate themselves by watching such television series since Malaysia is lacking in sexual education. This research consists of qualitative content analysis. The researcher had included the obscene visuals and dialogues in order to justify the existence of such sexual portrayal on the Grey＇s Anatomy TV series. A theory was selected for this study--the application on selected variables from a previous research done by the Henry J. Kaiser Family Foundation （Sex on TV4, 2005）. The researchers had found that such TV content could be a medium to promote safe sex messages since Malaysia lacks in sex education. The implication on theory was to distinguish the obscenity portrayal in TV series in shaping the audiences＇ acceptance.展开更多
In order to explain the phenomenon of negative capacitance（NC） in light emitting diodes LEDs, we present a new model based on local strong recombination in active region and firstly deduce the analytic expression of...In order to explain the phenomenon of negative capacitance（NC） in light emitting diodes LEDs, we present a new model based on local strong recombination in active region and firstly deduce the analytic expression of NO from continuity equation. The theoretical result indicates that the NC effect becomes stronger when the carrier recombination rate increases in a certain range,which is consistent with the experimental result. Accordingly,we confirm that the NO is caused by carrier recombination in active reaion instead of by other exterior factors.展开更多
The authors present several oscillation theorems for differential equation of second order （r（t）g（φ（x（t））x＇（t））＇＋q（t） f （x（t）） = 0and for differential equation with damping term Mx＂（t） ＋ p（t...The authors present several oscillation theorems for differential equation of second order （r（t）g（φ（x（t））x＇（t））＇＋q（t） f （x（t）） = 0and for differential equation with damping term Mx＂（t） ＋ p（t）x＇（t） ＋ q（t）x（t）=0where M〉 0, r（t） is positive continuous function. The conclusion is based also on building function where coefficients are involved in the equation and positive functions used by Philo H（t, s） and averaging techniques. Our results generalized, extend to some already known oscillation criteria in the literature. Also, here we give some applications of oscillation solution of. （1） and （2）, wherep（t） and q（t） are positive. The original purposes of differential equation are the mathematical formulation of the vibration frequency and the amplitude profile of a vibrating string with friction which the mass may have to encounter air resistance in its motion and in electric circuit containing an ac voltage source, an indicator, a capacitor, and a resistor in series is analyzed mathematically, the equation that results is a second order linear differential equation with oscillatory solution.展开更多
Photoelectrochemical （PEC） water splitting is a promising approach to harvest and store solar energy [1]. Silicon has been widely investigated for PEC photoelectrodes due to its suitable band gap （1.12 eV） matchin...Photoelectrochemical （PEC） water splitting is a promising approach to harvest and store solar energy [1]. Silicon has been widely investigated for PEC photoelectrodes due to its suitable band gap （1.12 eV） matching the solar spectrum [2]. Here we investigate employing nickel both as a catalyst and protecting layer of a p-type silicon photocathode for photoelectrochemical hydrogen evolution in basic electrolytes for the first time. The silicon photocathode was made by depositing 15 nm Ti on a p-type silicon wafer followed by 5 nm Ni. The photocathode afforded an onset potential of -0.3 V vs. the reversible hydrogen electrode （RHE） in alkaline solution （1 M KOH）. The stability of the Ni/Ti/p-Si photocathode showed a 100 mV decay over 12 h in KOH, but the stability was significantly improved when the photocathode was operated in potassium borate buffer solution （pH ≈ 9.5）. The electrode surface was found to remain intact after 12 h of continuous operation at a constant current density of 10 mA/cm^2 in potassium borate buffer, suggesting that Ni affords good protection of Si based photocathodes in borate buffers.展开更多
文摘为进一步提高有机废水的厌氧处理效率,同时实现能源物质的回收,采用微生物电解池并结合连续流工艺处理有机废水并同步回收甲烷,系统地研究不同水力停留时间、有机负荷、外加电压对微生物电解池内基质浓度的降解、甲烷生产速率等方面的影响.结果表明,在同一有机负荷下,随着外加电压(0.6 V,1.0 V,1.2 V)的升高,微生物电解池COD的去除效率和甲烷生产率也同时提高.在进水COD浓度为1 178 mg L-1、水力停留时间为8 h、外加电压为1.2V的条件下,其COD去除率、甲烷浓度、甲烷产生速率分别为97.7%、96%、1 071 m L L-1 d-1,较普通厌氧发酵(对照组)分别提高了31.5%、13.6%、123%;当进水COD浓度为4 812 mg L-1、水力停留时间为20 h、外加电压为1.2 V时,甲烷的产生速率达1 888 m L L-1 d-1,达理论产率的98.0%,而此条件下对照组甲烷产生速率仅为理论值的64.9%.说明连续流微生物电解池能够明显提高有机废水的处理效率,并实现处理过程中稳定回收甲烷的目的.高通量分析结果显示:微生物电解池阳极碳毡优势菌群为methanogens与Geobacter sp.,其丰度分别占总菌群的53.3%和7.5%,而对照组碳毡相应丰度仅为25.2%和0.7%.此外,研究发现有机负荷与电解池能量的消耗呈负相关,当外加电压为0.6 V时,有机负荷由3.5 kg m-3d-1提升至5.7 kg m-3d-1时,电解池能量消耗降低了79.3%.据此认为,通过优化水力停留时间和外加电压来处理有机废水并同步生产甲烷是可行的.
文摘The portrayal of obscenity in television series is not a new issue in our society. It is a reasonable fact to be understood, that the exposure to such explicit content of obscenity is acceptable in Western culture but somehow or rather, the acceptance of obscenity among the Asian society is still taboo and this has geared parents to pay greater attention to what type of media content should be watched by their children. The researcher believes the audience could also educate themselves by watching such television series since Malaysia is lacking in sexual education. This research consists of qualitative content analysis. The researcher had included the obscene visuals and dialogues in order to justify the existence of such sexual portrayal on the Grey＇s Anatomy TV series. A theory was selected for this study--the application on selected variables from a previous research done by the Henry J. Kaiser Family Foundation （Sex on TV4, 2005）. The researchers had found that such TV content could be a medium to promote safe sex messages since Malaysia lacks in sex education. The implication on theory was to distinguish the obscenity portrayal in TV series in shaping the audiences＇ acceptance.
基金This work was supported by the National Nature Science Foun-dation (Grant No.DMR-60376027) .
文摘In order to explain the phenomenon of negative capacitance（NC） in light emitting diodes LEDs, we present a new model based on local strong recombination in active region and firstly deduce the analytic expression of NO from continuity equation. The theoretical result indicates that the NC effect becomes stronger when the carrier recombination rate increases in a certain range,which is consistent with the experimental result. Accordingly,we confirm that the NO is caused by carrier recombination in active reaion instead of by other exterior factors.
文摘The authors present several oscillation theorems for differential equation of second order （r（t）g（φ（x（t））x＇（t））＇＋q（t） f （x（t）） = 0and for differential equation with damping term Mx＂（t） ＋ p（t）x＇（t） ＋ q（t）x（t）=0where M〉 0, r（t） is positive continuous function. The conclusion is based also on building function where coefficients are involved in the equation and positive functions used by Philo H（t, s） and averaging techniques. Our results generalized, extend to some already known oscillation criteria in the literature. Also, here we give some applications of oscillation solution of. （1） and （2）, wherep（t） and q（t） are positive. The original purposes of differential equation are the mathematical formulation of the vibration frequency and the amplitude profile of a vibrating string with friction which the mass may have to encounter air resistance in its motion and in electric circuit containing an ac voltage source, an indicator, a capacitor, and a resistor in series is analyzed mathematically, the equation that results is a second order linear differential equation with oscillatory solution.
文摘Photoelectrochemical （PEC） water splitting is a promising approach to harvest and store solar energy [1]. Silicon has been widely investigated for PEC photoelectrodes due to its suitable band gap （1.12 eV） matching the solar spectrum [2]. Here we investigate employing nickel both as a catalyst and protecting layer of a p-type silicon photocathode for photoelectrochemical hydrogen evolution in basic electrolytes for the first time. The silicon photocathode was made by depositing 15 nm Ti on a p-type silicon wafer followed by 5 nm Ni. The photocathode afforded an onset potential of -0.3 V vs. the reversible hydrogen electrode （RHE） in alkaline solution （1 M KOH）. The stability of the Ni/Ti/p-Si photocathode showed a 100 mV decay over 12 h in KOH, but the stability was significantly improved when the photocathode was operated in potassium borate buffer solution （pH ≈ 9.5）. The electrode surface was found to remain intact after 12 h of continuous operation at a constant current density of 10 mA/cm^2 in potassium borate buffer, suggesting that Ni affords good protection of Si based photocathodes in borate buffers.
