The potentially hazardous iron-containing sludge from the Fenton process requires proper treatment and disposal, which often results in high treatment cost. In this study, a novel method for the reuse of Fenton sludge...The potentially hazardous iron-containing sludge from the Fenton process requires proper treatment and disposal, which often results in high treatment cost. In this study, a novel method for the reuse of Fenton sludge as an iron source for the synthesis of nickel ferrite particles （NiFe204） is proposed. Through a co-precipitation method followed by sintering at 800℃, magnetic NiFe204 particles were successfully synthesized, which was confirmed by powder X-ray diffraction （XRD）, scanning electronic microscopy （SEM）, energy dispersive spectroscopy （EDS）, Fourier transform infrared spectroscopy （FT-IR） and Raman spectros- copy. The synthesized NiFe204 could be used as an efficient catalyst in the heterogeneous Fenton process. In phenol degradation with H202 or NiFe204 alone, the phenol removal efficiencies within the reaction time of 330 min were as low as 5.9% ±0.1% and 13.5% ± 0.4%, respectively. However, in the presence of both NiFe204 and H202, phenol removal efficiency as high as 95% ± 3.4% could be achieved, indicating the excellent catalytic performance of NiFe204 in the heterogeneous Fenton process. Notably, a rapid electron exchange between --NiH and --Fem ions in the NiFe204 structure could be beneficial for the Fenton reaction. In addition, the magnetic catalyst was relatively stable, highly active and recoverable, and has potential applications in the Fenton process for organic pollutant removal.展开更多
A combined zero valent iron （ZVI） and anaerobic-aerobic process was adopted for the treatment of 2,4-dinitrochlorobenzene （DNCB）- containing wastewater. The transformation pathway, reduction of acute toxicity and ...A combined zero valent iron （ZVI） and anaerobic-aerobic process was adopted for the treatment of 2,4-dinitrochlorobenzene （DNCB）- containing wastewater. The transformation pathway, reduction of acute toxicity and enhancement of biodegradability were investigated, After pretreatment by ZVI, DNCB in wastewater could be completely converted into 2,4-diaminochlorobenzene （DACB）. The ratio of BODs/COD increased from 0.005±0.001 to 0.168±0.007, while EC50,48hr （V/V） increased from 0.65% to 5.20%, indicating the enhancement of biodegradability and reduction of acute toxicity with the pretreatment by ZVI. DACB was further dechlorinated to m-phenylenediamine during the anaerobic process using methanol as electron donor, with EC50＇ 48 hr increasing from 5.20% to 48.2%. After the subsequent anaerobic-aerobic process, m-phenylenediamine was degraded completely, with effluent COD of 67.5±10.8 mg/L. This effluent of the subsequent anaerobic-aerobic process was not toxic to zebrafish. The combined ZVI and anaerobic-aerobic process offers bright prospects for the treatment of chlorinated nitroaromatic compound-containing wastewater.展开更多
Two pure hydrocarbon molecules of l,3,5-tris(9-phenyl-9H-fluoren-9-yl)benzene(mTPFB)and l,3,5-tris(2-tert-butyl-9-phenyl-9H-fluoren-9-yl)benzene(tBu-mTPFB)were synthesized.Due to the conjugation blocked connection mod...Two pure hydrocarbon molecules of l,3,5-tris(9-phenyl-9H-fluoren-9-yl)benzene(mTPFB)and l,3,5-tris(2-tert-butyl-9-phenyl-9H-fluoren-9-yl)benzene(tBu-mTPFB)were synthesized.Due to the conjugation blocked connection mode and rigid/bulky substitutions,these two materials possess high triplet energy,enabling them as good hosts for blue phosphor in PhOLEDs.By studying their thermal,electrochemical,electronic absorption and photoluminescent properties,it was found that the influence of the inert tert-butyl group on material photoelectrical properties is negligible.For instance,mTPFB and tBu-mTPFB showed very similar absorption and emission profiles,with almost the same bandgap,triplet energy and energy levels.However,the encapsulation of tert-butyl on the 2-position of 9-phenylfluorene enhanced material thermal stability.Most importantly,carrier transport properties were improved dramatically,as proved by the mono carrier device.Blue phosphorescent OLEDs hosted by tBu-mTPFB showed external quantum efficiency of 15.2%and current efficiency of 23.0 cd/A,which were much higher than that of the OLEDs based on mTPFB with the analogous structure.展开更多
Iridium(Ir)(Ⅲ)complexes with sufficient luminous efficiency and narrow full width at half maxima(FWHM)are required urgently for realizing organic light-emitting diodes(OLEDs)simultaneously with high electroluminescen...Iridium(Ir)(Ⅲ)complexes with sufficient luminous efficiency and narrow full width at half maxima(FWHM)are required urgently for realizing organic light-emitting diodes(OLEDs)simultaneously with high electroluminescence efficiency and good color purity.In this work,three novel main ligands incorporating the peripheral large steric hindrance units and rigid structures for efficiently suppressing the intermolecular stacking effect.展开更多
The objectives of this study were to establish an on-line controlling system for nitrogen and phosphorus removal synchronously of municipal wastewater in a sequencing batch reactor(SBR).The SBR for municipal wastewate...The objectives of this study were to establish an on-line controlling system for nitrogen and phosphorus removal synchronously of municipal wastewater in a sequencing batch reactor(SBR).The SBR for municipal wastewater treatment was operated in sequences:filling,anaerobic,oxic,anoxic,oxic,settling and discharge.The reactor was equipped with on-line monitoring sensors for dissolved oxygen(DO),oxidation-reduction potential(ORP)and pH.The variation of DO,ORP and pH is relevant to each phase of biological process for nitrogen and phosphorus removal in this SBR.The characteristic points of DO,ORP and pH can be used to judge and control the stages of process that include:phosphate release by the turning points of ORP and pH;nitrification by the ammonia valley of pH and ammonia elbows of DO and ORP;denitrification by the nitrate knee of ORP and nitrate apex of pH;phosphate uptake by the turning point of pH;and residual organic carbon oxida-tion by the carbon elbows of DO and ORP.The controlling system can operate automatically for nitrogen and phosphorus efficiently removal.展开更多
Generally,long wavelength absorbed near-infrared II(NIR-II)dyes have a low fluorescence efficiency in aggregate states for aggregate-caused quenching effect,simultaneously enhancing efficiency and extending absorption...Generally,long wavelength absorbed near-infrared II(NIR-II)dyes have a low fluorescence efficiency in aggregate states for aggregate-caused quenching effect,simultaneously enhancing efficiency and extending absorption is a challenging issue for NIR-II dyes.Here,three benzo[1,2-c:4,5-c’]bis[1,2,5]thiadiazole(BBT)derivatives(TPA-BBT,FT-BBT,and BTBT-BBT)are used to clarify fluorescence quenching mechanisms.When the BBT derivatives are doped into a small molecule matrix,they show quite different fluorescence behaviors.Structuredistorted TPA-BBT displays fluorescence quenching originating from short-range exchange interaction,while FT-BBT and BTBT-BBT with a co-planar-conjugated backbone exhibit concentration-dependent quenching processes,namely changing from long-range dipole-dipole interaction to exchange interaction,which could be majorly ascribed to large spectral overlap between absorption and emission.By precisely tuning doping concentration,both FT-BBT and BTBT-BBT nanoparticles(NPs)present the optimal NIR-II fluorescence brightness at∼2.5 wt%doping concentration.The doped NPs have good biocompatibility and could be served as fluorescence contrast agents for vascular imaging with a high resolution under 980-nm laser excitation.Those paradigms evidence that molecular doping can promote fluorescence efficiency of long wavelength-absorbed NIR-II fluorophores via suppressing long-range energy migration.展开更多
Flexible organic crystals are emerging as a potential candidate for smart materials and have aroused great interest over the past decade.In view of multicomponent supramolecular synthesis with a distinct advantage ove...Flexible organic crystals are emerging as a potential candidate for smart materials and have aroused great interest over the past decade.In view of multicomponent supramolecular synthesis with a distinct advantage over single-component approach on the control of molecular arrangements and physicochemical properties,we take note of various multicomponent flexible organic crystals in the range from organic co-crystals,supramolecular salts,solvates,doping organic crystals to solid solution crystals,showing a great diversity of supramolecular architectures such as one-dimensional columns,two-dimensional layer packing,and three-dimensional interlocked structures.Some of them serve as promising multifunctional materials with both flexibility and photoelectric properties such as fluorescence,optical waveguide,and ferroelectricity.In this review,we focus on the packing structures of multicomponent flexible organic crystals and their related mechanical properties,highlight typical research works,and point out the main possible directions that remain to be developed in this field.From the perspectives of crystal engineering and supramolecular chemistry,the flexible crystals outlined here should offer helpful information for further design and investigation on the elusive class of mechanically compliant crystalline compounds.展开更多
基金supported by the Major Project of Water Pollution Control and Management Technology of China(No.2012ZX07101-003-001)the Fundamental Research Funds for the Central Universities(No.30916011312)
文摘The potentially hazardous iron-containing sludge from the Fenton process requires proper treatment and disposal, which often results in high treatment cost. In this study, a novel method for the reuse of Fenton sludge as an iron source for the synthesis of nickel ferrite particles （NiFe204） is proposed. Through a co-precipitation method followed by sintering at 800℃, magnetic NiFe204 particles were successfully synthesized, which was confirmed by powder X-ray diffraction （XRD）, scanning electronic microscopy （SEM）, energy dispersive spectroscopy （EDS）, Fourier transform infrared spectroscopy （FT-IR） and Raman spectros- copy. The synthesized NiFe204 could be used as an efficient catalyst in the heterogeneous Fenton process. In phenol degradation with H202 or NiFe204 alone, the phenol removal efficiencies within the reaction time of 330 min were as low as 5.9% ±0.1% and 13.5% ± 0.4%, respectively. However, in the presence of both NiFe204 and H202, phenol removal efficiency as high as 95% ± 3.4% could be achieved, indicating the excellent catalytic performance of NiFe204 in the heterogeneous Fenton process. Notably, a rapid electron exchange between --NiH and --Fem ions in the NiFe204 structure could be beneficial for the Fenton reaction. In addition, the magnetic catalyst was relatively stable, highly active and recoverable, and has potential applications in the Fenton process for organic pollutant removal.
基金financed by the Innovation Program of Foundation Productthe National Natural Science Foundation of China (No.50978136, 51208258)+4 种基金the Major Project of Water Pollution Control and Management Technology of China (No.2012ZX07101-003-001)the Natural Science Foundation of Jiangsu Province (No.BK2011717)the China Post doctoral Science Foundation(No.2011M500927)the Jiangsu Planned Projects for Postdoctoral Research Funds (No.1101014C)the Fundamental Research Funds for Central Universities (No.NUST2011ZDJH20, NUST2011PYXM05)
文摘A combined zero valent iron （ZVI） and anaerobic-aerobic process was adopted for the treatment of 2,4-dinitrochlorobenzene （DNCB）- containing wastewater. The transformation pathway, reduction of acute toxicity and enhancement of biodegradability were investigated, After pretreatment by ZVI, DNCB in wastewater could be completely converted into 2,4-diaminochlorobenzene （DACB）. The ratio of BODs/COD increased from 0.005±0.001 to 0.168±0.007, while EC50,48hr （V/V） increased from 0.65% to 5.20%, indicating the enhancement of biodegradability and reduction of acute toxicity with the pretreatment by ZVI. DACB was further dechlorinated to m-phenylenediamine during the anaerobic process using methanol as electron donor, with EC50＇ 48 hr increasing from 5.20% to 48.2%. After the subsequent anaerobic-aerobic process, m-phenylenediamine was degraded completely, with effluent COD of 67.5±10.8 mg/L. This effluent of the subsequent anaerobic-aerobic process was not toxic to zebrafish. The combined ZVI and anaerobic-aerobic process offers bright prospects for the treatment of chlorinated nitroaromatic compound-containing wastewater.
基金supported by the National Natural Science Foundation of China(61474064,61504063)funding from Nanjing University of Posts and Telecommunications (NY214085,NY214177)+5 种基金the Natural Science Foundation of Jiangsu Province(BK20150836)the National Basic Research Program of China (2015CB932200)the National Synergistic Innovation Center for Advanced Materials(SICAM)Synergistic Innovation Center for Organic Electronics and Information DisplaysPriority Academic Program Development of Jiangsu Higher Education Institutions(PAPD,YX03001)funding from Key Laboratory for Organic Electronics & Information Displays
文摘Two pure hydrocarbon molecules of l,3,5-tris(9-phenyl-9H-fluoren-9-yl)benzene(mTPFB)and l,3,5-tris(2-tert-butyl-9-phenyl-9H-fluoren-9-yl)benzene(tBu-mTPFB)were synthesized.Due to the conjugation blocked connection mode and rigid/bulky substitutions,these two materials possess high triplet energy,enabling them as good hosts for blue phosphor in PhOLEDs.By studying their thermal,electrochemical,electronic absorption and photoluminescent properties,it was found that the influence of the inert tert-butyl group on material photoelectrical properties is negligible.For instance,mTPFB and tBu-mTPFB showed very similar absorption and emission profiles,with almost the same bandgap,triplet energy and energy levels.However,the encapsulation of tert-butyl on the 2-position of 9-phenylfluorene enhanced material thermal stability.Most importantly,carrier transport properties were improved dramatically,as proved by the mono carrier device.Blue phosphorescent OLEDs hosted by tBu-mTPFB showed external quantum efficiency of 15.2%and current efficiency of 23.0 cd/A,which were much higher than that of the OLEDs based on mTPFB with the analogous structure.
基金supported by the National Natural Science Foundation of China(22005158)the Program of High Level Talents(No.03083064 and JSSCBS20211122)the Large Instruments Open Foundation of Nantong University,and the Nantong Science and Technology Planning Project(social people’s livelihood)(MS12020048).
文摘Iridium(Ir)(Ⅲ)complexes with sufficient luminous efficiency and narrow full width at half maxima(FWHM)are required urgently for realizing organic light-emitting diodes(OLEDs)simultaneously with high electroluminescence efficiency and good color purity.In this work,three novel main ligands incorporating the peripheral large steric hindrance units and rigid structures for efficiently suppressing the intermolecular stacking effect.
基金This work was supported by the National Natural Science Foundation of China(Grant No.50138010)Key Laboratory Open Foundation of Beijing.
文摘The objectives of this study were to establish an on-line controlling system for nitrogen and phosphorus removal synchronously of municipal wastewater in a sequencing batch reactor(SBR).The SBR for municipal wastewater treatment was operated in sequences:filling,anaerobic,oxic,anoxic,oxic,settling and discharge.The reactor was equipped with on-line monitoring sensors for dissolved oxygen(DO),oxidation-reduction potential(ORP)and pH.The variation of DO,ORP and pH is relevant to each phase of biological process for nitrogen and phosphorus removal in this SBR.The characteristic points of DO,ORP and pH can be used to judge and control the stages of process that include:phosphate release by the turning points of ORP and pH;nitrification by the ammonia valley of pH and ammonia elbows of DO and ORP;denitrification by the nitrate knee of ORP and nitrate apex of pH;phosphate uptake by the turning point of pH;and residual organic carbon oxida-tion by the carbon elbows of DO and ORP.The controlling system can operate automatically for nitrogen and phosphorus efficiently removal.
基金NNSF,Grant/Award Numbers:62120106002,22175089Jiangsu Provincial Policy Key Research and Development Plan,Grant/Award Numbers:BE2021711,BE2022812+1 种基金open research fund of State Key Laboratory of Organic Electronics and Information DisplaysStartup Foundation for Introducing Talent of NUIST,Grant/Award Number:2021r089。
文摘Generally,long wavelength absorbed near-infrared II(NIR-II)dyes have a low fluorescence efficiency in aggregate states for aggregate-caused quenching effect,simultaneously enhancing efficiency and extending absorption is a challenging issue for NIR-II dyes.Here,three benzo[1,2-c:4,5-c’]bis[1,2,5]thiadiazole(BBT)derivatives(TPA-BBT,FT-BBT,and BTBT-BBT)are used to clarify fluorescence quenching mechanisms.When the BBT derivatives are doped into a small molecule matrix,they show quite different fluorescence behaviors.Structuredistorted TPA-BBT displays fluorescence quenching originating from short-range exchange interaction,while FT-BBT and BTBT-BBT with a co-planar-conjugated backbone exhibit concentration-dependent quenching processes,namely changing from long-range dipole-dipole interaction to exchange interaction,which could be majorly ascribed to large spectral overlap between absorption and emission.By precisely tuning doping concentration,both FT-BBT and BTBT-BBT nanoparticles(NPs)present the optimal NIR-II fluorescence brightness at∼2.5 wt%doping concentration.The doped NPs have good biocompatibility and could be served as fluorescence contrast agents for vascular imaging with a high resolution under 980-nm laser excitation.Those paradigms evidence that molecular doping can promote fluorescence efficiency of long wavelength-absorbed NIR-II fluorophores via suppressing long-range energy migration.
基金supported by the National Natural Science Foundation of China(Nos.22205105,22075136)the National Key Basic Research Program of China(No.2020YFA0709900)+2 种基金the Natural Science Foundation of Jiangsu Province(No.BK20200700)the open research fund from the State Key Laboratory of Luminescent Materials and Devices(South China University of Technology)the Anhui Province Key Laboratory of Optoelectric Materials Science and Technology(No.OMST202101).
文摘Flexible organic crystals are emerging as a potential candidate for smart materials and have aroused great interest over the past decade.In view of multicomponent supramolecular synthesis with a distinct advantage over single-component approach on the control of molecular arrangements and physicochemical properties,we take note of various multicomponent flexible organic crystals in the range from organic co-crystals,supramolecular salts,solvates,doping organic crystals to solid solution crystals,showing a great diversity of supramolecular architectures such as one-dimensional columns,two-dimensional layer packing,and three-dimensional interlocked structures.Some of them serve as promising multifunctional materials with both flexibility and photoelectric properties such as fluorescence,optical waveguide,and ferroelectricity.In this review,we focus on the packing structures of multicomponent flexible organic crystals and their related mechanical properties,highlight typical research works,and point out the main possible directions that remain to be developed in this field.From the perspectives of crystal engineering and supramolecular chemistry,the flexible crystals outlined here should offer helpful information for further design and investigation on the elusive class of mechanically compliant crystalline compounds.
