Gold nanoparticles have been increasingly used in catalysis, biomedical imaging, biological and chemical sensing, drug delivery, etc. In this study, a straightforward method that allows one to monitor the synthesis of...Gold nanoparticles have been increasingly used in catalysis, biomedical imaging, biological and chemical sensing, drug delivery, etc. In this study, a straightforward method that allows one to monitor the synthesis of gold sols and their aging, before their fine characterization by sophisticated techniques and before their use is described. Indeed, the “Colloid Thin-Layer Chromatography” method allows one to check the quality of gold colloidal sols during the synthesis. It is also well adapted for monitoring the aging of the sol before the visual observation of its degradation.展开更多
An on-chip reference voltage has been designed in capacitor-resister hybrid SAR ADC for CZT detec- tor with the TSMC 0.35 μm 2P4M CMOS process. The voltage reference has a dynamic load since using variable capacitors...An on-chip reference voltage has been designed in capacitor-resister hybrid SAR ADC for CZT detec- tor with the TSMC 0.35 μm 2P4M CMOS process. The voltage reference has a dynamic load since using variable capacitors and resistances, which need a large driving ability to deal with the current related to the time and sampling rate. Most of the previous articles about the reference for ADC present only the bandgap part for a low temperature coefficient and high PSRR. However, it is not enough and overall, it needs to consider the output driving ability. The proposed voltage reference is realized by the band-gap reference, voltage generator and output buffer. Apart from a low temperature coefficient and high PSRR, it has the features of a large driving ability and low power con- sumption. What is more, for CZT detectors application in space, a radiation-hardened design has been considered. The measurement results show that the output reference voltage of the buffer is 4.096 V. When the temperature varied from 0 to 80 ℃, the temperature coefficient is 12.2 ppm/℃. The PSRR was -70 dB @ 100 kHz. The drive current of the reference can reach up to 10 mA. The area of the voltage reference in the SAR ADC chip is only 449 × 614μm2. The total power consumption is only 1.092 mW.展开更多
Two major steps in field studies of wild animals have been their tagging and,more recently,their instrumen-tation with transmitters and loggers.While the contribution of both to our scientific knowledge is immense,the...Two major steps in field studies of wild animals have been their tagging and,more recently,their instrumen-tation with transmitters and loggers.While the contribution of both to our scientific knowledge is immense,the extent to which the data are reliable and therefore unbi-ased is however generally unknown.Yet,there is now evidence that,even in trained animals,human presence induces a long-lasting stress which is aggravated by capture and handling in order to either attach or recover the instruments,or to take biological samples.Moreover,attached tags and loggers result in a disturbance,partic-ularly for aquatic animals due to the increased drag in water.To determine the relative and overall impact of such disturbances and therefore to select or develop the best possible new instrumentation,it is obviously necessary to get data on undisturbed control animals or at least evaluate the magnitude of the effects of distur-bance on the parameters of interest.展开更多
文摘Gold nanoparticles have been increasingly used in catalysis, biomedical imaging, biological and chemical sensing, drug delivery, etc. In this study, a straightforward method that allows one to monitor the synthesis of gold sols and their aging, before their fine characterization by sophisticated techniques and before their use is described. Indeed, the “Colloid Thin-Layer Chromatography” method allows one to check the quality of gold colloidal sols during the synthesis. It is also well adapted for monitoring the aging of the sol before the visual observation of its degradation.
基金supported by the National Key Scientific Instrument and Equipment Development Project(No.2011YQ040082)the National Natural Science Foundation of China(No.61376034)the Shaanxi Province Science and Technology Innovation Project(No.2015KTZDGY03-03)
文摘An on-chip reference voltage has been designed in capacitor-resister hybrid SAR ADC for CZT detec- tor with the TSMC 0.35 μm 2P4M CMOS process. The voltage reference has a dynamic load since using variable capacitors and resistances, which need a large driving ability to deal with the current related to the time and sampling rate. Most of the previous articles about the reference for ADC present only the bandgap part for a low temperature coefficient and high PSRR. However, it is not enough and overall, it needs to consider the output driving ability. The proposed voltage reference is realized by the band-gap reference, voltage generator and output buffer. Apart from a low temperature coefficient and high PSRR, it has the features of a large driving ability and low power con- sumption. What is more, for CZT detectors application in space, a radiation-hardened design has been considered. The measurement results show that the output reference voltage of the buffer is 4.096 V. When the temperature varied from 0 to 80 ℃, the temperature coefficient is 12.2 ppm/℃. The PSRR was -70 dB @ 100 kHz. The drive current of the reference can reach up to 10 mA. The area of the voltage reference in the SAR ADC chip is only 449 × 614μm2. The total power consumption is only 1.092 mW.
文摘Two major steps in field studies of wild animals have been their tagging and,more recently,their instrumen-tation with transmitters and loggers.While the contribution of both to our scientific knowledge is immense,the extent to which the data are reliable and therefore unbi-ased is however generally unknown.Yet,there is now evidence that,even in trained animals,human presence induces a long-lasting stress which is aggravated by capture and handling in order to either attach or recover the instruments,or to take biological samples.Moreover,attached tags and loggers result in a disturbance,partic-ularly for aquatic animals due to the increased drag in water.To determine the relative and overall impact of such disturbances and therefore to select or develop the best possible new instrumentation,it is obviously necessary to get data on undisturbed control animals or at least evaluate the magnitude of the effects of distur-bance on the parameters of interest.
