Magnetic microspherical β-cyclodextrin（CD）/Fe3O4@polyvinylpyrrolidone（PVP） particles, in which embedded Fe3O4 particles were coated by β-CD/glutaraldehyde crosslinked PVP, were synthesized via electrostatic spra...Magnetic microspherical β-cyclodextrin（CD）/Fe3O4@polyvinylpyrrolidone（PVP） particles, in which embedded Fe3O4 particles were coated by β-CD/glutaraldehyde crosslinked PVP, were synthesized via electrostatic spray and thermal crosslinking technologies. The magnetic microspheres were characterized by infrared spectroscopy, X-ray diffraction, scanning electron microscopy（SEM） and magnetic measurements, and the adsorption performance of the β-CD/Fe3O4@PVP composite nanoparticles for methyl orange was studied. The results show that the β-CD/Fe304@PVP microspheres could be quickly separated from the adsorption system under an external magnetic field within 30 s and that the adsorption capacity of the microspheres for methyl orange reaches greater than 90%, with a maximum adsorption quantity of 47.62 mg/g.展开更多
Chiral organoeatalysts of 4-adamantane amide based on L-proline with double hydrogen potential were synthesized and used in asymmetric aldol reactions. The reactions were evaluated in toluene under -20℃. A series of ...Chiral organoeatalysts of 4-adamantane amide based on L-proline with double hydrogen potential were synthesized and used in asymmetric aldol reactions. The reactions were evaluated in toluene under -20℃. A series of aldol products was obtained from moderate to good yields（up to 98%） with excellent diastereoselectivities（up to 〉99：1） and enantioselectivities（up to 〉99%）. The aldol products m the system were separated by a-cyclodextrin via host-guest interaction and determined by chiral HPLC. The catalyst could be reused up to five times. The 4-substitution position played an important role in diastereoselectivitv and enantioselectivitv.展开更多
By a simple one-step reaction, a new fluorescein-based probe, 3'-hydroxy-3-oxo-3H-spiro[isobenzofuran-l,9'-xanthen]-6-yl-4-bromobutanoate(FLB), was designed and synthesized. Relative to other cations, anions o...By a simple one-step reaction, a new fluorescein-based probe, 3'-hydroxy-3-oxo-3H-spiro[isobenzofuran-l,9'-xanthen]-6-yl-4-bromobutanoate(FLB), was designed and synthesized. Relative to other cations, anions or amines, the probe exhibited high sensitivity and specificity towards hydrazine with approximate 40-fold fluorescence enliancement at 515 nm. The detection limit(DL) was calculated to be 2.87×10^-8 mol/L, which was about 10 times lower than maximum allowable level of hydraziiie(3.12 ×1mol/L) in drinking water pennitted by the US Environment and Protection Association(EPA). Simultaneously, tlirough mass spectroscopy and proton nuclear magnetic resonance titration, the detection mechanism was further confirmed. Eventually, due to the low cytotoxicity and excellent water solubility, FLB could be employed to detect hydrazine in living cells.展开更多
A novel water-soluble hybrid fluorescein-coumarin dye（FLNC） fluorescence ratiometric probe to recognize OCl^- was designed and synthesized. The most prominent feature of the probe is that the molecular structure con...A novel water-soluble hybrid fluorescein-coumarin dye（FLNC） fluorescence ratiometric probe to recognize OCl^- was designed and synthesized. The most prominent feature of the probe is that the molecular structure contains two different fluorophores, and the fluorescein moiety was connected to coumarin moiety by diacylhydrazine linker. When OCl was added, the two fluorophores in the FLNC probe could have a rapid respond simulta- neously, with high selectivity and sensitivity towards OCl^- among other reactive oxygen species/reactive nitrogen species（ROS/RNS） and anions, and the detection limit was measured to be 0.30 μmol/L. In addition, the color changes of the solution could be observed by the naked eye and have a short response time（completed within 1 min）, which suggestes that the probe FLNC has the potential to be used for real-time detection.展开更多
Microfiber reinforced nanofiber films were prepared with the help of two nozzles technology.We designed a new device via placing two nozzles on the opposite sides of a rolling cylinder,with a piece of thin insulation ...Microfiber reinforced nanofiber films were prepared with the help of two nozzles technology.We designed a new device via placing two nozzles on the opposite sides of a rolling cylinder,with a piece of thin insulation board with a certain size of hole in the middle part installed to accommodate the cylinder so as to form two entirely independent electric fields.Playing the role of support,microfiber may be favorable for enhancing the mechanic performance of the nanofiber.Compared with that of single nanofiber,the tensile strength of the composite micro/nanofiber prepared by this method has been increased by a factor of 4.5.After the further improvement of the fiber orientation,the tensile strength is 7.96 times that of non-oriented composite micro/nanofibers film,30 times that of the single nanofiber film.展开更多
文摘Magnetic microspherical β-cyclodextrin（CD）/Fe3O4@polyvinylpyrrolidone（PVP） particles, in which embedded Fe3O4 particles were coated by β-CD/glutaraldehyde crosslinked PVP, were synthesized via electrostatic spray and thermal crosslinking technologies. The magnetic microspheres were characterized by infrared spectroscopy, X-ray diffraction, scanning electron microscopy（SEM） and magnetic measurements, and the adsorption performance of the β-CD/Fe3O4@PVP composite nanoparticles for methyl orange was studied. The results show that the β-CD/Fe304@PVP microspheres could be quickly separated from the adsorption system under an external magnetic field within 30 s and that the adsorption capacity of the microspheres for methyl orange reaches greater than 90%, with a maximum adsorption quantity of 47.62 mg/g.
基金Supported by the National Natural Science Foundation of China（No.21174052） and the Natural Science Foundation of Jilin Province of China（Nos.20160101311JC, 20170101105JC）.
文摘Chiral organoeatalysts of 4-adamantane amide based on L-proline with double hydrogen potential were synthesized and used in asymmetric aldol reactions. The reactions were evaluated in toluene under -20℃. A series of aldol products was obtained from moderate to good yields（up to 98%） with excellent diastereoselectivities（up to 〉99：1） and enantioselectivities（up to 〉99%）. The aldol products m the system were separated by a-cyclodextrin via host-guest interaction and determined by chiral HPLC. The catalyst could be reused up to five times. The 4-substitution position played an important role in diastereoselectivitv and enantioselectivitv.
基金Supported by the National Natural Science Foundation of China(No.21174052) and the Natural Science Foundation of Jilin Province, China(No.20170101105JC).
文摘By a simple one-step reaction, a new fluorescein-based probe, 3'-hydroxy-3-oxo-3H-spiro[isobenzofuran-l,9'-xanthen]-6-yl-4-bromobutanoate(FLB), was designed and synthesized. Relative to other cations, anions or amines, the probe exhibited high sensitivity and specificity towards hydrazine with approximate 40-fold fluorescence enliancement at 515 nm. The detection limit(DL) was calculated to be 2.87×10^-8 mol/L, which was about 10 times lower than maximum allowable level of hydraziiie(3.12 ×1mol/L) in drinking water pennitted by the US Environment and Protection Association(EPA). Simultaneously, tlirough mass spectroscopy and proton nuclear magnetic resonance titration, the detection mechanism was further confirmed. Eventually, due to the low cytotoxicity and excellent water solubility, FLB could be employed to detect hydrazine in living cells.
基金Supported by the Natural Science Foundation of Jilin Province, China（Nos.20160101311JC, 20170101105 JC ） and the Jilin Provincial Science and Technology Research Plan, China（No.20170204039GX）.
文摘A novel water-soluble hybrid fluorescein-coumarin dye（FLNC） fluorescence ratiometric probe to recognize OCl^- was designed and synthesized. The most prominent feature of the probe is that the molecular structure contains two different fluorophores, and the fluorescein moiety was connected to coumarin moiety by diacylhydrazine linker. When OCl was added, the two fluorophores in the FLNC probe could have a rapid respond simulta- neously, with high selectivity and sensitivity towards OCl^- among other reactive oxygen species/reactive nitrogen species（ROS/RNS） and anions, and the detection limit was measured to be 0.30 μmol/L. In addition, the color changes of the solution could be observed by the naked eye and have a short response time（completed within 1 min）, which suggestes that the probe FLNC has the potential to be used for real-time detection.
基金Supported by the National Natural Science Foundation of China（Nos.20674023,20874033）.
文摘Microfiber reinforced nanofiber films were prepared with the help of two nozzles technology.We designed a new device via placing two nozzles on the opposite sides of a rolling cylinder,with a piece of thin insulation board with a certain size of hole in the middle part installed to accommodate the cylinder so as to form two entirely independent electric fields.Playing the role of support,microfiber may be favorable for enhancing the mechanic performance of the nanofiber.Compared with that of single nanofiber,the tensile strength of the composite micro/nanofiber prepared by this method has been increased by a factor of 4.5.After the further improvement of the fiber orientation,the tensile strength is 7.96 times that of non-oriented composite micro/nanofibers film,30 times that of the single nanofiber film.
