Here,we designed asymmetric(m DS)and symmetrical(d DS)chiral V-shaped molecules by linking one or two dansyl groups to trans-1,2-cyclohexane diamine and investigated the solvent-regulated structural transformation and...Here,we designed asymmetric(m DS)and symmetrical(d DS)chiral V-shaped molecules by linking one or two dansyl groups to trans-1,2-cyclohexane diamine and investigated the solvent-regulated structural transformation and inversed circularly polarized luminescence(CPL)in the self-assemblies.Upon increasing water volume fraction(fw)in the mixed solvent of water/acetonitrile,asymmetric mDS selfassembled into hollow nanospheres and microtubes,while solid nanospheres and solid microplates were corresponding to symmetric d DS.During this transformation process,the emission of m DS and d DS was changed from yellow-green to blue and cyan color,which was ascribed to twisted intramolecular charge transfer(TICT)and locally excited(LE)fluorescence of V-shaped DS molecules.The conformation of N,Ndimethyl groups with respect to naphthalene ring also led to the transformation of structures.These tubular and platelike structures had stronger and reversed CPL signals in comparison with spheroidal structures.The chiral information of DS assembly could be effective transferred to achiral Nile red via co-assembly strategy,which endowed Nile red exhibiting inversed induced CPL signal regulated by water fraction.This work provides a method for achieving a variety of self-assembled structures with adjustable chiroptical properties.展开更多
To realize the handedness controllable circularly polarized luminescence(CPL) system remains challenging. Herein, the solvent-mediated CPL inversion and amplification systems were successfully constructed by camptothe...To realize the handedness controllable circularly polarized luminescence(CPL) system remains challenging. Herein, the solvent-mediated CPL inversion and amplification systems were successfully constructed by camptothecin derivative(CPT-A). Due to the planar structure of N,N-dimethylformamide, it could coassemble with CPT-A, resulting in the alteration of g_(lum) from –0.0082 to +0.0085 by increasing water content. While in the non-planar solvent(hexafluoroisopropanol), the g_(lum) was amplified to 0.034 with the increase in water content. Moreover, the CPT-A could react with the glutathione, resulting in the anticancer drug CPT to make it more toxic to the cancer cells. Overall, the handedness controllable CPL systems were realized by tuning the supramolecular self-assembly of a prodrug.展开更多
Membrane fouling is one of the major obstacles for reaching a high flux over a prolonged period of ultrafiltration（UF）process.In this study,a sulfonated-polyethersulfone（SPES）/nano-TiO2 composite UF membrane with ...Membrane fouling is one of the major obstacles for reaching a high flux over a prolonged period of ultrafiltration（UF）process.In this study,a sulfonated-polyethersulfone（SPES）/nano-TiO2 composite UF membrane with good anti-fouling performance was fabricated by phase inversion and self-assembly methods.The TiO2 nanoparticle self-assembly on the SPES membrane surface was confirmed by X-ray photoelectron spectroscopy （XPS）and FT-IR spectrometer.The morphology and hydrophilicity were characterized by scanning electron microscopy（SEM）,atomic force microscopy（AFM）and contact angle goniometer,respectively.The anti-fouling mechanism of composite UF membrane was discussed through the analysis of the micro-structure and component of UF membrane surface.The results showed that the TiO2 content and the micro-structure of the composite UF membrane surface had great influence on the separation and anti-fouling performance.展开更多
The utilization of biomass has attracted much attention during the last decade. Sorbitol is a kind of abundant biomass with multiple chiral centers in its skeleton, indicating an im- portant potential for helical arch...The utilization of biomass has attracted much attention during the last decade. Sorbitol is a kind of abundant biomass with multiple chiral centers in its skeleton, indicating an im- portant potential for helical architectures. Helical nanostruc- tures with switchable chirality are attracting much attention due to their crucial roles in many fields.展开更多
Chiral mesoporous silica ribbons and rods with inversed handedness have been synthesized with the same enantio pure N-acylaminoacidat temperatures of 0℃and 20℃ respectively. With involving Cu^(2+)and meso-tetra(4-su...Chiral mesoporous silica ribbons and rods with inversed handedness have been synthesized with the same enantio pure N-acylaminoacidat temperatures of 0℃and 20℃ respectively. With involving Cu^(2+)and meso-tetra(4-sulfonatophenyl)porphyrin(TPPS) as probes, ribbons and rods revealed opposite signals in diffuse-reflectance circular dichroism(DRCD) spectra, indicating the existence of inversed supramolecular chiral imprintings through helical stacking of amphiphiles. The structural evolution was systematically studied by the freeze-dried products sampled at different time after the addition of silica precursors. The H-bonding-depended molecular orientation probably controls the chiral sense upon forming chiral molecular stacking, which would be the origin of such handedness inversion展开更多
Nanoparticles with high surface energy and chemical activity have drawn substantial attention in petroleum industry. Recently, Janus nanoparticles exhibited tremendous potential in enhanced oil recovery (EOR) due to t...Nanoparticles with high surface energy and chemical activity have drawn substantial attention in petroleum industry. Recently, Janus nanoparticles exhibited tremendous potential in enhanced oil recovery (EOR) due to their asymmetric structures and properties. In this study, a series of amphiphilic pseudo-Janus@OTAB (PJ@C18) nanoparticles with different concentrations of stearyltrimethylammoium bromide (OTAB) were successfully fabricated. The structures and properties of PJ@C18 were characterized by Fourier transform infrared spectroscopy and ζ-potential measurements. Based on the emulsification experimental results, the interaction models and the self-assembly behavior between hydrophilic nanoparticles (SiO_(2)@NH_(2)) and OTAB molecules at the oil/water interface were proposed, which was further confirmed via the measurements of the contact angle and dynamic interfacial tension. Interestingly, it was found that the change of pH value from 7.5 to 4.0 caused the type reversal of the PJ@C18-1000 stabilized Pickering emulsions. Furthermore, the PJ@C18-1000 stabilized Pickering emulsion system with excellent salt and temperature tolerances (10000 mg∙L^(–1), 90℃) significantly improved the oil recovery in the single-tube (more than 17%) and double-tube (more than 25%) sand pack model flooding tests. The findings of this study could help to better understand the construction mechanism of pseudo-Janus silica/surfactant assembly and the potential application of PJ@C18-1000 stabilized Pickering emulsions for EOR.展开更多
基金financial support from the National Key R&D Program of China(No.2021YFA1200301)the National Natural Science Foundation of China(Nos.21890734,92156018,and 21972150)CAS Project for Young Scientists in Basic Research(No.YSBR-027)。
文摘Here,we designed asymmetric(m DS)and symmetrical(d DS)chiral V-shaped molecules by linking one or two dansyl groups to trans-1,2-cyclohexane diamine and investigated the solvent-regulated structural transformation and inversed circularly polarized luminescence(CPL)in the self-assemblies.Upon increasing water volume fraction(fw)in the mixed solvent of water/acetonitrile,asymmetric mDS selfassembled into hollow nanospheres and microtubes,while solid nanospheres and solid microplates were corresponding to symmetric d DS.During this transformation process,the emission of m DS and d DS was changed from yellow-green to blue and cyan color,which was ascribed to twisted intramolecular charge transfer(TICT)and locally excited(LE)fluorescence of V-shaped DS molecules.The conformation of N,Ndimethyl groups with respect to naphthalene ring also led to the transformation of structures.These tubular and platelike structures had stronger and reversed CPL signals in comparison with spheroidal structures.The chiral information of DS assembly could be effective transferred to achiral Nile red via co-assembly strategy,which endowed Nile red exhibiting inversed induced CPL signal regulated by water fraction.This work provides a method for achieving a variety of self-assembled structures with adjustable chiroptical properties.
基金the National Natural Science Foundation of China (No. 22101280)Wenzhou Medical University (No. KYYW201901)+1 种基金University of Chinese Academy of Science (Nos. WIBEZD201700103 and WIUCASQD2020005)Zhejiang Provincial Natural Science Foundation (No. LQ20B020009) for financial support。
文摘To realize the handedness controllable circularly polarized luminescence(CPL) system remains challenging. Herein, the solvent-mediated CPL inversion and amplification systems were successfully constructed by camptothecin derivative(CPT-A). Due to the planar structure of N,N-dimethylformamide, it could coassemble with CPT-A, resulting in the alteration of g_(lum) from –0.0082 to +0.0085 by increasing water content. While in the non-planar solvent(hexafluoroisopropanol), the g_(lum) was amplified to 0.034 with the increase in water content. Moreover, the CPT-A could react with the glutathione, resulting in the anticancer drug CPT to make it more toxic to the cancer cells. Overall, the handedness controllable CPL systems were realized by tuning the supramolecular self-assembly of a prodrug.
基金Supported by the Natural Science Foundation of Shandong Province（Q2007B01）
文摘Membrane fouling is one of the major obstacles for reaching a high flux over a prolonged period of ultrafiltration（UF）process.In this study,a sulfonated-polyethersulfone（SPES）/nano-TiO2 composite UF membrane with good anti-fouling performance was fabricated by phase inversion and self-assembly methods.The TiO2 nanoparticle self-assembly on the SPES membrane surface was confirmed by X-ray photoelectron spectroscopy （XPS）and FT-IR spectrometer.The morphology and hydrophilicity were characterized by scanning electron microscopy（SEM）,atomic force microscopy（AFM）and contact angle goniometer,respectively.The anti-fouling mechanism of composite UF membrane was discussed through the analysis of the micro-structure and component of UF membrane surface.The results showed that the TiO2 content and the micro-structure of the composite UF membrane surface had great influence on the separation and anti-fouling performance.
基金Supported by the National Natural Science Foundation of China（No.21503238） and the National Key Research and Deve- lopment Program of China（No.2017YFA0403003）.
文摘The utilization of biomass has attracted much attention during the last decade. Sorbitol is a kind of abundant biomass with multiple chiral centers in its skeleton, indicating an im- portant potential for helical architectures. Helical nanostruc- tures with switchable chirality are attracting much attention due to their crucial roles in many fields.
基金supported by the National Natural Science Foundation of China (Nos. 21471099, 21601123)
文摘Chiral mesoporous silica ribbons and rods with inversed handedness have been synthesized with the same enantio pure N-acylaminoacidat temperatures of 0℃and 20℃ respectively. With involving Cu^(2+)and meso-tetra(4-sulfonatophenyl)porphyrin(TPPS) as probes, ribbons and rods revealed opposite signals in diffuse-reflectance circular dichroism(DRCD) spectra, indicating the existence of inversed supramolecular chiral imprintings through helical stacking of amphiphiles. The structural evolution was systematically studied by the freeze-dried products sampled at different time after the addition of silica precursors. The H-bonding-depended molecular orientation probably controls the chiral sense upon forming chiral molecular stacking, which would be the origin of such handedness inversion
基金funding from the National Natural Science Foundation of China(Grant No.51974344)the Natural Science Foundation of Shandong Provincial(Grant No.ZR2019MEE077)the Fundamental Research Funds for the Central Universities(Grant No.19CX02064A).
文摘Nanoparticles with high surface energy and chemical activity have drawn substantial attention in petroleum industry. Recently, Janus nanoparticles exhibited tremendous potential in enhanced oil recovery (EOR) due to their asymmetric structures and properties. In this study, a series of amphiphilic pseudo-Janus@OTAB (PJ@C18) nanoparticles with different concentrations of stearyltrimethylammoium bromide (OTAB) were successfully fabricated. The structures and properties of PJ@C18 were characterized by Fourier transform infrared spectroscopy and ζ-potential measurements. Based on the emulsification experimental results, the interaction models and the self-assembly behavior between hydrophilic nanoparticles (SiO_(2)@NH_(2)) and OTAB molecules at the oil/water interface were proposed, which was further confirmed via the measurements of the contact angle and dynamic interfacial tension. Interestingly, it was found that the change of pH value from 7.5 to 4.0 caused the type reversal of the PJ@C18-1000 stabilized Pickering emulsions. Furthermore, the PJ@C18-1000 stabilized Pickering emulsion system with excellent salt and temperature tolerances (10000 mg∙L^(–1), 90℃) significantly improved the oil recovery in the single-tube (more than 17%) and double-tube (more than 25%) sand pack model flooding tests. The findings of this study could help to better understand the construction mechanism of pseudo-Janus silica/surfactant assembly and the potential application of PJ@C18-1000 stabilized Pickering emulsions for EOR.
