Energy harvesting is an area of substantial and increasing research attention, and vibration-based devices dominate this research. The primary goal of most researchers is producing maximum electrical output from the h...Energy harvesting is an area of substantial and increasing research attention, and vibration-based devices dominate this research. The primary goal of most researchers is producing maximum electrical output from the harvester systems. However, there have been little metrological considerations for circumstances under which the energy harvester devices are characterized. This makes comparison of different device prototypes very difficult. It is the focus of this paper to highlight the need for metrological considerations to energy harvesting so that a universal metric can be developed. An attempt is also made to discuss the critical parameters that are essential in establishing an international standard on vibration-based energy harvesting. Finally, a simple standard for energy harvesting is proposed.展开更多
Interaction of a drug molecule with human serum albumin (HSA) is usually studied by fluorescence responses of the ligand or/and the single tryptophan residue (Trp-214) of the protein, but qualitative spectral info...Interaction of a drug molecule with human serum albumin (HSA) is usually studied by fluorescence responses of the ligand or/and the single tryptophan residue (Trp-214) of the protein, but qualitative spectral information may lead to multiple conclusions. In this work, we report a study on the interaction of hematoporphyrin monomethyl ether (HMME) with human serum albumin (HSA), using the environment-sensitive spectra of HMME and reaction-induced fluorescence response of Trp-214. Particularly, the single kinetic parameter, the linear slope, was derived from the concentration-dependent absorbance or fluorescence of HMME in a certain solvent. A quantitative change in the slope at [HMME]/[HSA] = 1 : 1 clearly demonstrated a specific binding of HMME to site I. The microenvironment in site I may be comparable to that in DMSO solvent, because of the similarity of the slope. Linear correlation of the fluorescence to the absorbance of HMME in site I indicates that the energy transfer is not responsible for Trp-214 fluorescence quenching but an electron transfer may be possible. In addition, much higher rate observed for the binding of HMME or 2-taurine-substituted HB (THB) with HSA than that of hypocrellin B was due to the electrostatic attraction under physiological condition.展开更多
文摘Energy harvesting is an area of substantial and increasing research attention, and vibration-based devices dominate this research. The primary goal of most researchers is producing maximum electrical output from the harvester systems. However, there have been little metrological considerations for circumstances under which the energy harvester devices are characterized. This makes comparison of different device prototypes very difficult. It is the focus of this paper to highlight the need for metrological considerations to energy harvesting so that a universal metric can be developed. An attempt is also made to discuss the critical parameters that are essential in establishing an international standard on vibration-based energy harvesting. Finally, a simple standard for energy harvesting is proposed.
基金National Natural Science Foundation of China(Grant No.20872144)
文摘Interaction of a drug molecule with human serum albumin (HSA) is usually studied by fluorescence responses of the ligand or/and the single tryptophan residue (Trp-214) of the protein, but qualitative spectral information may lead to multiple conclusions. In this work, we report a study on the interaction of hematoporphyrin monomethyl ether (HMME) with human serum albumin (HSA), using the environment-sensitive spectra of HMME and reaction-induced fluorescence response of Trp-214. Particularly, the single kinetic parameter, the linear slope, was derived from the concentration-dependent absorbance or fluorescence of HMME in a certain solvent. A quantitative change in the slope at [HMME]/[HSA] = 1 : 1 clearly demonstrated a specific binding of HMME to site I. The microenvironment in site I may be comparable to that in DMSO solvent, because of the similarity of the slope. Linear correlation of the fluorescence to the absorbance of HMME in site I indicates that the energy transfer is not responsible for Trp-214 fluorescence quenching but an electron transfer may be possible. In addition, much higher rate observed for the binding of HMME or 2-taurine-substituted HB (THB) with HSA than that of hypocrellin B was due to the electrostatic attraction under physiological condition.