Adsorption reactions between surfaces of nanodiamond and nanosilica with diameter of 100 nm prepared as suspension solutions of 0.25μg/μL and lysozyme molecule with different concentrations of 7 mmol/L PPBS at pH=7,...Adsorption reactions between surfaces of nanodiamond and nanosilica with diameter of 100 nm prepared as suspension solutions of 0.25μg/μL and lysozyme molecule with different concentrations of 7 mmol/L PPBS at pH=7, 9, 11, and 13 have been investigated by fluores- cence spectroscopy. Adsorption reaction constants and coverages of lysozyme with different concentrations of 0-1000 nmol/L under the influences of different pH values have been ob- tained. Helicities and conformations of the adsorbed lysozyme molecules, free spaces of every adsorbed lysozyme molecule on the surfaces of nanopartieles at different concentrations and pH values have been deduced and discussed. The highest adsorption capabilities for both sys- tems and conformational efficiency of the adsorbed lysozyme molecule at pH=13 have been obtained. Lysozyme molecules can be prepared, adsorbed and carried with optimal activity and helicity, with 2 and 10 mg/m2 on unit nanosurface, 130 and 150 mg/g with respect to the weight of nanoparticle, within the linear regions of the coverages at around 150-250 nmol/L and four pH values for nanodiamond and nanosilica, respectively. They can be prepared in the tightest packed form, with 20 and 55 mg/m2, 810-1680 and 580-1100 mg/g at threshold concentrations and four pH values for nanodiamond and nanosilica, respectively.展开更多
Laboratory discovery of new phosphors for white-light light-emitting diodes （WLEDs） is still an im- perative challenge. A new yellow-emitting Sr9MgLi（PO4）7：Eu^2＋ phosphor was discovered based on the mineral-insp...Laboratory discovery of new phosphors for white-light light-emitting diodes （WLEDs） is still an im- perative challenge. A new yellow-emitting Sr9MgLi（PO4）7：Eu^2＋ phosphor was discovered based on the mineral-inspired pro- totype evolution and new phase construction strategy pro- posed by our group. Sr9MgLi（PO4）7：Eu^2＋ has been synthesized by using a high temperature solid-state method, and its phase structure and luminescence properties have been investigated in detail, and applied in WLED lamp. Sr9MgLi（PO4）7 phase is derived from the ]3-Ca3（PO4）2-type mineral structure. Upon 365 nm UV light excitation, the SrgMgLi（PO4）7：Eu^2＋ phosphor exhibits a broad emission band from 450 nm to 700 nm. The white-light LED lamp was fabricated based on the phosphor blends of the composition-optimized yellow-emitting Sr9MgLi （PO4）7：Eu2＋ and commercial blue-emitting BaMgAl10O17：Eu^2＋, and a 365 nm UV chip was used as the excitation source. The Ra, CCT value and CIE of the as-fabricated LEDs were found to be 83, 5,612 K, and （0.324, 0.358）, respectively. All the results indicate that Sr9MgLi（PO4）7：Eu^2＋ could be potential in the development of UV-pumped white-light LEDs.展开更多
文摘Adsorption reactions between surfaces of nanodiamond and nanosilica with diameter of 100 nm prepared as suspension solutions of 0.25μg/μL and lysozyme molecule with different concentrations of 7 mmol/L PPBS at pH=7, 9, 11, and 13 have been investigated by fluores- cence spectroscopy. Adsorption reaction constants and coverages of lysozyme with different concentrations of 0-1000 nmol/L under the influences of different pH values have been ob- tained. Helicities and conformations of the adsorbed lysozyme molecules, free spaces of every adsorbed lysozyme molecule on the surfaces of nanopartieles at different concentrations and pH values have been deduced and discussed. The highest adsorption capabilities for both sys- tems and conformational efficiency of the adsorbed lysozyme molecule at pH=13 have been obtained. Lysozyme molecules can be prepared, adsorbed and carried with optimal activity and helicity, with 2 and 10 mg/m2 on unit nanosurface, 130 and 150 mg/g with respect to the weight of nanoparticle, within the linear regions of the coverages at around 150-250 nmol/L and four pH values for nanodiamond and nanosilica, respectively. They can be prepared in the tightest packed form, with 20 and 55 mg/m2, 810-1680 and 580-1100 mg/g at threshold concentrations and four pH values for nanodiamond and nanosilica, respectively.
基金supported by the National Natural Science Foundation of China (51722202, 91622125 and 51572023)Natural Science Foundation of Beijing (2172036)
文摘Laboratory discovery of new phosphors for white-light light-emitting diodes （WLEDs） is still an im- perative challenge. A new yellow-emitting Sr9MgLi（PO4）7：Eu^2＋ phosphor was discovered based on the mineral-inspired pro- totype evolution and new phase construction strategy pro- posed by our group. Sr9MgLi（PO4）7：Eu^2＋ has been synthesized by using a high temperature solid-state method, and its phase structure and luminescence properties have been investigated in detail, and applied in WLED lamp. Sr9MgLi（PO4）7 phase is derived from the ]3-Ca3（PO4）2-type mineral structure. Upon 365 nm UV light excitation, the SrgMgLi（PO4）7：Eu^2＋ phosphor exhibits a broad emission band from 450 nm to 700 nm. The white-light LED lamp was fabricated based on the phosphor blends of the composition-optimized yellow-emitting Sr9MgLi （PO4）7：Eu2＋ and commercial blue-emitting BaMgAl10O17：Eu^2＋, and a 365 nm UV chip was used as the excitation source. The Ra, CCT value and CIE of the as-fabricated LEDs were found to be 83, 5,612 K, and （0.324, 0.358）, respectively. All the results indicate that Sr9MgLi（PO4）7：Eu^2＋ could be potential in the development of UV-pumped white-light LEDs.
