The factors influencing the crystallization ratio of mold flux were researched by rapid cooling technolo gy, and the factors affecting crystallization temperature were studied by single thermocouple technique. The res...The factors influencing the crystallization ratio of mold flux were researched by rapid cooling technolo gy, and the factors affecting crystallization temperature were studied by single thermocouple technique. The results showed that the crystallization ratio of mold flux increases with the basicity and the content of Na2O, CaF2, Li2O and NaF, and decreases with the increase of the content of Al2O3, MgO, BaO, MnO and B2O3. However, the crystallization temperature of mold flux rises with the basicity and the content of NaF, Na2O and CaF2, and reduces with the increase of the content of Al2O3, MgO, BaO, MnO and B2O3. But for Li2O, crystallization temperature decreases firstly to a minimum value at 2%, and then increases gradually with the increase of Li2O.展开更多
The experimental study on negative capacitance（NO） of various light-emitting diodes（LEDs） is presented. Experimental result shows that all LEDs display the NO phenomenon. The voltage modulated electroluminescence...The experimental study on negative capacitance（NO） of various light-emitting diodes（LEDs） is presented. Experimental result shows that all LEDs display the NO phenomenon. The voltage modulated electroluminescence（VMEL） experiment confirms that the reason of negative capacitance is the strong recombination of the injected carriers in the active region of luminescence. The measures also verify that the dependence of NO on voltage and frequency in different LEDs is similar. NO phenomenon is more obvious with higher voltage or lower frequency.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
文摘The factors influencing the crystallization ratio of mold flux were researched by rapid cooling technolo gy, and the factors affecting crystallization temperature were studied by single thermocouple technique. The results showed that the crystallization ratio of mold flux increases with the basicity and the content of Na2O, CaF2, Li2O and NaF, and decreases with the increase of the content of Al2O3, MgO, BaO, MnO and B2O3. However, the crystallization temperature of mold flux rises with the basicity and the content of NaF, Na2O and CaF2, and reduces with the increase of the content of Al2O3, MgO, BaO, MnO and B2O3. But for Li2O, crystallization temperature decreases firstly to a minimum value at 2%, and then increases gradually with the increase of Li2O.
基金This workis supported by the National Nature Science Founda-tion (Grant No.DMR-60376027)
文摘The experimental study on negative capacitance（NO） of various light-emitting diodes（LEDs） is presented. Experimental result shows that all LEDs display the NO phenomenon. The voltage modulated electroluminescence（VMEL） experiment confirms that the reason of negative capacitance is the strong recombination of the injected carriers in the active region of luminescence. The measures also verify that the dependence of NO on voltage and frequency in different LEDs is similar. NO phenomenon is more obvious with higher voltage or lower frequency.
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.
