Recent baby formula milk powder contamination incidents have shown that the classic markers or standards in milk quality control are insufficient in identifying ＂manipulated＂ poor-quality milk. In the present study,...Recent baby formula milk powder contamination incidents have shown that the classic markers or standards in milk quality control are insufficient in identifying ＂manipulated＂ poor-quality milk. In the present study, we demonstrated for the first time that cow milk contains large amounts of microRNAs （miRNAs） and that the unique expression profile of milk-specific miRNAs can serve as a novel indicator and possible new standard for the quafity control of raw milk and milk-related commercial products, such as fluid milk and powdered formula milk. First, using Solexa sequencing, we systematically screened miRNA expression in raw milk and identified a total of 245 miR- NAs in raw milk. Unlike other classic biomarkers whose expression levels are nearly identical at different periods of lactation, individual miRNAs can be significantly altered during lactation process, implicating that miRNAs may be a more accurate indicator to reflect the quality alteration of milk. Second, using TaqMan probe-based miRNA quantitative RT-PCR, we further identified seven miRNAs that have a relatively consistent expression throughout the lactation process, and more importantly, the expression profile of these seven milk-specific miRNAs can serve as an ideal biomarker for discriminating poor-quality or ＂manipulated＂ milk from pure raw milk, as well as for the quality control of commercial milk products, such as fluid milk and powdered formula milk. Together, our findings provide a basis for understanding the physiological role of milk miRNAs and a new potential standard for determining the quality of raw milk or milk-related commercial products.展开更多
The design and construction of heterojunction photocatalysts,which possess a staggered energy band structure and appropriate interfacial contact,is an effective way to achieve outstanding photocatalytic performance.In...The design and construction of heterojunction photocatalysts,which possess a staggered energy band structure and appropriate interfacial contact,is an effective way to achieve outstanding photocatalytic performance.In this study,2D/2D BiOBr/g‐C_(3)N_(4)heterojunctions were successfully obtained by a convenient in situ self‐assembly route.Under simulated sunlight irradiation,99%of RhB(10 mg·L–1,100 mL)was efficiently degraded by 1.5‐BiOBr/g‐C_(3)N_(4)within 30 min,which is better than the performance of both BiOBr and g‐C_(3)N_(4),and it has superior stability.In addition,the composite also exhibits enhanced photocatalytic activity for H2 production.The enhanced activity can be attributed to the intimate interface contact,the larger surface area,and the highly efficient separation of photoinduced electron–hole pairs.Based on the experimental results,a novel S‐scheme model was proposed to illuminate the transfer process of charge carriers.This study presents a simple way to develop novel step‐scheme photocatalysts for environmental and related applications.展开更多
Two-dimensional mesoporous ultrathin Cd0.5Zn0.5S nanosheets with a thickness of~1.5 nm were fabricated using a multistep chemical transformation strategy involving inorganic–organic hybrid ZnS-ethylenediamine(denoted...Two-dimensional mesoporous ultrathin Cd0.5Zn0.5S nanosheets with a thickness of~1.5 nm were fabricated using a multistep chemical transformation strategy involving inorganic–organic hybrid ZnS-ethylenediamine(denoted as ZnS(en)0.5)as a hard template.Inorganic–organic hybrid ZnS(en)0.5,Cd0.5Zn0.5S(en)x,and Cd0.5Zn0.5S nanosheets were sequentially fabricated,and their transformation processes were analyzed in detail.The fabricated Cd0.5Zn0.5S nanosheets exhibited high photocatalytic hydrogen evolution reaction activity in the presence of a sacrificial agent.The Cd0.5Zn0.5S nanosheets exhibited remarkably high H2 production activity of~1395μmol∙h^−1∙g^−1 in pure water with no co-catalyst,which is the highest value reported thus far for bare photocatalysts,to the best of our knowledge.The high activity of these nanosheets is attributed to their distinct nanostructure(e.g.,short transfer distance of photoinduced charge carriers,large number of unsaturated surface atoms,and large surface area).Moreover,ternary NiCo2S4 nanoparticles were employed to facilitate the charge separation and enhance the surface kinetics of H2 evolution.The H2 production rate reached~62.2 and~2436μmol∙h^−1∙g^−1 in triethanolamine and pure water,respectively,over the NiCo2S4/Cd0.5Zn0.5S heterojunctions.The result indicated that the Schottky junction was critical to the enhanced activity.The proposed method can be used for fabricating other highly efficient CdZnS-based photocatalysts for solar-energy conversion or other applications.展开更多
Ag nanoparticles (NPs) were deposited on the surface of g-C3N4 (CN) by an in situ calcination method. NiS was successfully loaded onto the composites by a hydrothermal method. The results showed that the 10 wt%-NiS/1....Ag nanoparticles (NPs) were deposited on the surface of g-C3N4 (CN) by an in situ calcination method. NiS was successfully loaded onto the composites by a hydrothermal method. The results showed that the 10 wt%-NiS/1.0 wt%-Ag/CN composite exhibits excellent photocatalytic H2 generation performance under solar-light irradiation. An H2 production rate of 9.728 mmol·g^-1·h^-1 was achieved, which is 10.82-, 3.45-, and 2.77-times higher than those of pure g-C3N4, 10 wt%-NiS/CN, and 1.0 wt%-Ag/CN composites, respectively. This enhanced photocatalytic H2 generation can be ascribed to the co-decoration of Ag and NiS on the surface of g-C3N4, which efficiently improves light harvesting capacity, photogenerated charge carrier separation, and photocatalytic H2 production kinetics. Thus, this study demonstrates an effective strategy for constructing excellent g-C3N4-related composite photocatalysts for H2 production by using different co-catalysts.展开更多
In this work,a novel plasmon-assisted UV-vis-NIR-driven W_(18)O_(49)/Cd_(0.5)Zn_(0.5)S heterostructure photocatalyst was obtained by a facile ultrasonic-assisted electrostatic self-assembly strategy.The hybrid exhibit...In this work,a novel plasmon-assisted UV-vis-NIR-driven W_(18)O_(49)/Cd_(0.5)Zn_(0.5)S heterostructure photocatalyst was obtained by a facile ultrasonic-assisted electrostatic self-assembly strategy.The hybrid exhibits extraordinary H2 evolution activity of 147.7 mmol·g^(-1)·h^(-1) at room temperature due to the efficient charge separation and expanded light absorption.Our investigation shows that the unique Step-scheme(S-scheme)charge transfer and the‘hot electron’injection are both responsible for the extraordinary H2 evolution process,depending on the wavelength of the incident light.Moreover,by accelerating the surface reaction kinetics,the activity can be further elevated to 306.1 mmol·g^(-1)·h^(-1),accompanied by a high apparent quantum yield of 45.3% at 365±7.5 nm.This work provides us a potential strategy for the highly efficient conversion of the solar energy by elaborately combining a nonstoichiometric ratio plasmonic material with an appropriate active photocatalyst.展开更多
Nickel-cobalt/silicon carbide(Ni-Co/SiC)composite coatings were fabricated by supergravity field-enhanced electrodeposition.The surface morphology and the distribution of the SiC particles in the coatings were examine...Nickel-cobalt/silicon carbide(Ni-Co/SiC)composite coatings were fabricated by supergravity field-enhanced electrodeposition.The surface morphology and the distribution of the SiC particles in the coatings were examined by scanning electron microscope and energy dispersive X-ray spectrometry.The preferred orientations of the coatings were measured by X-ray diffractometry.The wear resistance and microhardness were measured by a reciprocating tribometer and a microhardness instrument,respectively.The results revealed that the use of the supergravity field enhanced the smoothness of the as-deposited Ni-Co/SiC coatings,and the SiC nanoparticles were uniformly distributed in comparison with that for conventional electrodeposition.When the rotation speed of the cathode,which provided the supergravity field,was 800 r/min,the SiC content in the coating reached a maximum of 8.1 wt%,which was a much higher content than the 2.2 wt%value obtained under conventional electrodeposition.The highest coating microhardness of 680 HV was also observed at this rotation speed.In addition,the wear resistance of the as-prepared Ni-Co/SiC coatings exhibited improved performance relative to that prepared under normal gravity.A minimum wear weight loss of 1.4 mg together with an average friction coefficient of 0.13 were also realized at a rotation speed of 800 r/min,values which were much lower than those for normal gravity.展开更多
Based on the population floating theory under the Ranis-Fei dual economic structure,this paper designs an econometric model to study the isoquant curve and production factor substitution law. Finally,through the empir...Based on the population floating theory under the Ranis-Fei dual economic structure,this paper designs an econometric model to study the isoquant curve and production factor substitution law. Finally,through the empirical analysis of labor-capital investment in Henan's agricultural production,combined with the principles of isoquant curve model,this paper determines the labor required for a certain scale of investment in agricultural production,and concludes that the fixed assets investment in Henan's agricultural production is not fully utilized,and too much labor is transferred. And this paper makes the corresponding policy recommendations for Henan's macroeconomic development.展开更多
Smart materials that integrate multi-stimuli response,full reversibility,and dual-visual read-out channel are highly desired for anticounterfeiting and information encryption applications.Herein,we developed a multire...Smart materials that integrate multi-stimuli response,full reversibility,and dual-visual read-out channel are highly desired for anticounterfeiting and information encryption applications.Herein,we developed a multiresponsive perchlorate terpyridyl Pt(Ⅱ)nano complex which could undergo fully reversible conversion between three forms stimulated by water or formaldehyde molecule due to the extent of Pt–Pt interaction.Meanwhile,a dual-visual channel,i.e.,the colorimetric channel changed from yellow to orange or red and the corresponding luminescent channel from orange to orange-red or red,has also been found.The weak and equivalent strength of ion-dipole interaction and hydrogen bond that generated between formaldehyde/water and Pt(II)salt result in the easy-control reversibility between the three forms.Furthermore,by introducing different polymer matrices,1Cl·ClO_(4)@PMMA(1Cl·ClO_(4):[Pt(tpy)Cl]·ClO4,tpy:2,2':6',2''-terpyridine),PMMA:poly(methyl methacrylate))and 1Cl·ClO4@PVA(PVA:polyvinyl alcohol)are successfully constructed,which exhibit different reversible behaviors since the PMMA and PVA matrix exert different influences on the strength of hydrogen-bond.Those smart Pt(II)salt nanostructures present great potential for high-security-level anticounterfeiting application.展开更多
The field of nanomedicine has emerged as a vital component in cancer treatment modalities over the past decades.Covalent organic frameworks(COFs)at the nanoscale have become a novel and promising category of biomateri...The field of nanomedicine has emerged as a vital component in cancer treatment modalities over the past decades.Covalent organic frameworks(COFs)at the nanoscale have become a novel and promising category of biomaterials in the field of nanomedicine.Their distinctive properties,such as low density,exceptional porosity,crystalline structure,remarkable thermal stability,versatile functionality,and biocompatibility,contribute to their significant potential in cancer therapy applications.This review firstly discusses COFs with various morphologies in theranostic applications.The primary morphologies of COFs for tumors treatment can be categorized into four types:nanospheres,nanosheets,nano-rods/tubes and nanoparticles.Furthermore,we review recent research articles and systematically discuss recent advancements in COFs for chemotherapy,chemodynamic therapy,photodynamic therapy,photothermal therapy and combination therapy.In conclusion,we outline the current obstacles and potential future directions for this distinctive research area.展开更多
Wire electrochemical machining(WECM) is a flexible and effective method for machining complex-shaped metal components, but the ability to machine large-thickness workpieces is hampered by the difficulty of transportin...Wire electrochemical machining(WECM) is a flexible and effective method for machining complex-shaped metal components, but the ability to machine large-thickness workpieces is hampered by the difficulty of transporting electrolytic products in the narrow machining gap. This paper proposes a novel hybrid machining technique that combines the characteristics of WECM and wire electric discharge machining(WEDM), namely, helical wire electrochemical discharge machining. The formation mechanism of electrical discharge in salt-glycol solution was elucidated.Experiments and simulation were conducted to verify the machining mechanism and investigate the performance of the proposed technique. The results show that as the recast layer can be removed by electrochemical action during the proposed process, the surface quality is effectively improved.Minimum surface roughness of the slit sidewall after machining reaches Ra= 0.12 μm. Minimum standard deviation of the slit after machining reaches 5 μm. Moreover, the existence of the discharges significantly improves the transport of the electrolytic products, thus ensuring high machining efficiency. In the experiments, the maximum feed rate of the helical wire electrochemical discharge machining reaches 7 μm/s(12.6 mm^(2)/min). Finally, mortise structures of Inconel 718 with good machining accuracy and surface quality are fabricated with a feed rate of 5 μm/s(9 mm^(2)/min),demonstrating that electrical discharge assisted helical wire ECM is a promising technique for machining large-thickness hard metal materials.展开更多
The precise regulation of interactions provided by aggregation-induced emission(AIE)probes is of considerable significance for improving the sensing performance in the field of on-site detection.Here,a highly sensitiv...The precise regulation of interactions provided by aggregation-induced emission(AIE)probes is of considerable significance for improving the sensing performance in the field of on-site detection.Here,a highly sensitive perchlorate detection probe was designed by precisely modulating the van der Waals interactions by adjusting the length of the alkyl chain.The optimized AIE probe demonstrated superior perchlorate detection performance owing to its strong van der Waals interactions with perchlorate,including a low detection limit(53.81 nM),rapid response(<5 s),and excellent specificity even in the presence of 16 interfering anions.In addition,a hydrogel-based device loaded with the probe was constructed to achieve ultrasensitive recognition of perchlorate particles with a detection limit as low as 15 fg under a fluorescence microscope.Moreover,the practicality of the probe was further verified by employing a sensing chip in a portable detector,and thus the probe has been proven to be highly promising for trace perchlorate monitoring in real scenarios.We expect the present study to be of great value for the efficient design of high-performance fluorescent probes.展开更多
Flexible quantum dot light-emitting diodes(QLEDs)show great promise for the next generation of flexible,wearable,and artificial intelligence display applications.However,the performance of flexible QLEDs still lags be...Flexible quantum dot light-emitting diodes(QLEDs)show great promise for the next generation of flexible,wearable,and artificial intelligence display applications.However,the performance of flexible QLEDs still lags behind that of rigid substrate devices,hindering their commercialization for display applications.Here we report the superior performance of flexible QLEDs based on efficient red ZnCdSe/ZnS/ZnSe QDs(A-QDs)with antitype-I nanostructures.We reveal that using ZnS as an intermediate shell can effectively confine the exciton wavefunction to the inner core,reducing the surface sensitivity of the QDs and maintaining its excellent emission properties.These flexible QLEDs exhibit a peak external quantum efficiency of 23.0%and a long lifetime of 63,050 h,respectively.The anti-type-I nanostructure of A-QDs in the device simultaneously suppresses defectinduced nonradiative recombination and balances carrier injection,achieving the most excellent performance of flexible QLEDs ever reported.This study provides new insights into achieving superior performance in flexible QD-based electroluminescent devices.展开更多
基金This work was supported by grants from the National Natural Science Foundation of China （30225037, 30471991, 30570731）, the 973 Program of China （2006CB503909, 2004CB518603）, the ＂111＂ Project, and the Natural Science Foundation of Jiangsu Province （BK2004082, BIC2006714）.
文摘Recent baby formula milk powder contamination incidents have shown that the classic markers or standards in milk quality control are insufficient in identifying ＂manipulated＂ poor-quality milk. In the present study, we demonstrated for the first time that cow milk contains large amounts of microRNAs （miRNAs） and that the unique expression profile of milk-specific miRNAs can serve as a novel indicator and possible new standard for the quafity control of raw milk and milk-related commercial products, such as fluid milk and powdered formula milk. First, using Solexa sequencing, we systematically screened miRNA expression in raw milk and identified a total of 245 miR- NAs in raw milk. Unlike other classic biomarkers whose expression levels are nearly identical at different periods of lactation, individual miRNAs can be significantly altered during lactation process, implicating that miRNAs may be a more accurate indicator to reflect the quality alteration of milk. Second, using TaqMan probe-based miRNA quantitative RT-PCR, we further identified seven miRNAs that have a relatively consistent expression throughout the lactation process, and more importantly, the expression profile of these seven milk-specific miRNAs can serve as an ideal biomarker for discriminating poor-quality or ＂manipulated＂ milk from pure raw milk, as well as for the quality control of commercial milk products, such as fluid milk and powdered formula milk. Together, our findings provide a basis for understanding the physiological role of milk miRNAs and a new potential standard for determining the quality of raw milk or milk-related commercial products.
文摘The design and construction of heterojunction photocatalysts,which possess a staggered energy band structure and appropriate interfacial contact,is an effective way to achieve outstanding photocatalytic performance.In this study,2D/2D BiOBr/g‐C_(3)N_(4)heterojunctions were successfully obtained by a convenient in situ self‐assembly route.Under simulated sunlight irradiation,99%of RhB(10 mg·L–1,100 mL)was efficiently degraded by 1.5‐BiOBr/g‐C_(3)N_(4)within 30 min,which is better than the performance of both BiOBr and g‐C_(3)N_(4),and it has superior stability.In addition,the composite also exhibits enhanced photocatalytic activity for H2 production.The enhanced activity can be attributed to the intimate interface contact,the larger surface area,and the highly efficient separation of photoinduced electron–hole pairs.Based on the experimental results,a novel S‐scheme model was proposed to illuminate the transfer process of charge carriers.This study presents a simple way to develop novel step‐scheme photocatalysts for environmental and related applications.
文摘Two-dimensional mesoporous ultrathin Cd0.5Zn0.5S nanosheets with a thickness of~1.5 nm were fabricated using a multistep chemical transformation strategy involving inorganic–organic hybrid ZnS-ethylenediamine(denoted as ZnS(en)0.5)as a hard template.Inorganic–organic hybrid ZnS(en)0.5,Cd0.5Zn0.5S(en)x,and Cd0.5Zn0.5S nanosheets were sequentially fabricated,and their transformation processes were analyzed in detail.The fabricated Cd0.5Zn0.5S nanosheets exhibited high photocatalytic hydrogen evolution reaction activity in the presence of a sacrificial agent.The Cd0.5Zn0.5S nanosheets exhibited remarkably high H2 production activity of~1395μmol∙h^−1∙g^−1 in pure water with no co-catalyst,which is the highest value reported thus far for bare photocatalysts,to the best of our knowledge.The high activity of these nanosheets is attributed to their distinct nanostructure(e.g.,short transfer distance of photoinduced charge carriers,large number of unsaturated surface atoms,and large surface area).Moreover,ternary NiCo2S4 nanoparticles were employed to facilitate the charge separation and enhance the surface kinetics of H2 evolution.The H2 production rate reached~62.2 and~2436μmol∙h^−1∙g^−1 in triethanolamine and pure water,respectively,over the NiCo2S4/Cd0.5Zn0.5S heterojunctions.The result indicated that the Schottky junction was critical to the enhanced activity.The proposed method can be used for fabricating other highly efficient CdZnS-based photocatalysts for solar-energy conversion or other applications.
基金supported by the National Natural Science Foundation of China(21676213,21476183,51372201)the China Postdoctoral Science Foundation(2016M600809)the Natural Science Basic Research Plan in Shaanxi Province of China(2017JM2026)~~
文摘Ag nanoparticles (NPs) were deposited on the surface of g-C3N4 (CN) by an in situ calcination method. NiS was successfully loaded onto the composites by a hydrothermal method. The results showed that the 10 wt%-NiS/1.0 wt%-Ag/CN composite exhibits excellent photocatalytic H2 generation performance under solar-light irradiation. An H2 production rate of 9.728 mmol·g^-1·h^-1 was achieved, which is 10.82-, 3.45-, and 2.77-times higher than those of pure g-C3N4, 10 wt%-NiS/CN, and 1.0 wt%-Ag/CN composites, respectively. This enhanced photocatalytic H2 generation can be ascribed to the co-decoration of Ag and NiS on the surface of g-C3N4, which efficiently improves light harvesting capacity, photogenerated charge carrier separation, and photocatalytic H2 production kinetics. Thus, this study demonstrates an effective strategy for constructing excellent g-C3N4-related composite photocatalysts for H2 production by using different co-catalysts.
文摘In this work,a novel plasmon-assisted UV-vis-NIR-driven W_(18)O_(49)/Cd_(0.5)Zn_(0.5)S heterostructure photocatalyst was obtained by a facile ultrasonic-assisted electrostatic self-assembly strategy.The hybrid exhibits extraordinary H2 evolution activity of 147.7 mmol·g^(-1)·h^(-1) at room temperature due to the efficient charge separation and expanded light absorption.Our investigation shows that the unique Step-scheme(S-scheme)charge transfer and the‘hot electron’injection are both responsible for the extraordinary H2 evolution process,depending on the wavelength of the incident light.Moreover,by accelerating the surface reaction kinetics,the activity can be further elevated to 306.1 mmol·g^(-1)·h^(-1),accompanied by a high apparent quantum yield of 45.3% at 365±7.5 nm.This work provides us a potential strategy for the highly efficient conversion of the solar energy by elaborately combining a nonstoichiometric ratio plasmonic material with an appropriate active photocatalyst.
基金National Key Research and Development Program of China(Grant No.2018YFB1105900)National Basic Research Program of China(973 Program,Grant No.2015CB057502)Fundamental Research Funds for the Central Universities(Grant No.NZ2016106).
文摘Nickel-cobalt/silicon carbide(Ni-Co/SiC)composite coatings were fabricated by supergravity field-enhanced electrodeposition.The surface morphology and the distribution of the SiC particles in the coatings were examined by scanning electron microscope and energy dispersive X-ray spectrometry.The preferred orientations of the coatings were measured by X-ray diffractometry.The wear resistance and microhardness were measured by a reciprocating tribometer and a microhardness instrument,respectively.The results revealed that the use of the supergravity field enhanced the smoothness of the as-deposited Ni-Co/SiC coatings,and the SiC nanoparticles were uniformly distributed in comparison with that for conventional electrodeposition.When the rotation speed of the cathode,which provided the supergravity field,was 800 r/min,the SiC content in the coating reached a maximum of 8.1 wt%,which was a much higher content than the 2.2 wt%value obtained under conventional electrodeposition.The highest coating microhardness of 680 HV was also observed at this rotation speed.In addition,the wear resistance of the as-prepared Ni-Co/SiC coatings exhibited improved performance relative to that prepared under normal gravity.A minimum wear weight loss of 1.4 mg together with an average friction coefficient of 0.13 were also realized at a rotation speed of 800 r/min,values which were much lower than those for normal gravity.
基金Supported by Fund Project of Hubei Provincial Institute of New Countryside Development
文摘Based on the population floating theory under the Ranis-Fei dual economic structure,this paper designs an econometric model to study the isoquant curve and production factor substitution law. Finally,through the empirical analysis of labor-capital investment in Henan's agricultural production,combined with the principles of isoquant curve model,this paper determines the labor required for a certain scale of investment in agricultural production,and concludes that the fixed assets investment in Henan's agricultural production is not fully utilized,and too much labor is transferred. And this paper makes the corresponding policy recommendations for Henan's macroeconomic development.
基金support from the Major Science and Technology Project of Xinjiang(No.2022A01006-3)Science Foundation for Outstanding Young People of Xinjiang(No.2022D01E40)+1 种基金Youth Science Foundation of Xinjiang(No.2022D01C69)Tianchi Doctoral program(Nos.TCBS202130 and 51052300573).
文摘Smart materials that integrate multi-stimuli response,full reversibility,and dual-visual read-out channel are highly desired for anticounterfeiting and information encryption applications.Herein,we developed a multiresponsive perchlorate terpyridyl Pt(Ⅱ)nano complex which could undergo fully reversible conversion between three forms stimulated by water or formaldehyde molecule due to the extent of Pt–Pt interaction.Meanwhile,a dual-visual channel,i.e.,the colorimetric channel changed from yellow to orange or red and the corresponding luminescent channel from orange to orange-red or red,has also been found.The weak and equivalent strength of ion-dipole interaction and hydrogen bond that generated between formaldehyde/water and Pt(II)salt result in the easy-control reversibility between the three forms.Furthermore,by introducing different polymer matrices,1Cl·ClO_(4)@PMMA(1Cl·ClO_(4):[Pt(tpy)Cl]·ClO4,tpy:2,2':6',2''-terpyridine),PMMA:poly(methyl methacrylate))and 1Cl·ClO4@PVA(PVA:polyvinyl alcohol)are successfully constructed,which exhibit different reversible behaviors since the PMMA and PVA matrix exert different influences on the strength of hydrogen-bond.Those smart Pt(II)salt nanostructures present great potential for high-security-level anticounterfeiting application.
基金supported by the National Natural Science Foundation of China(22234005 and 21974070)the Natural Science Foundation of Jiangsu Province(BK20222015)+1 种基金the Young Academic Leaders of the Qing Lan Project of Jiangsu Province(SUJIAOSHIHAN[2022]No.29)the Industry-University-Research Cooperation Program of Jiangsu Province(BY20230054).
文摘The field of nanomedicine has emerged as a vital component in cancer treatment modalities over the past decades.Covalent organic frameworks(COFs)at the nanoscale have become a novel and promising category of biomaterials in the field of nanomedicine.Their distinctive properties,such as low density,exceptional porosity,crystalline structure,remarkable thermal stability,versatile functionality,and biocompatibility,contribute to their significant potential in cancer therapy applications.This review firstly discusses COFs with various morphologies in theranostic applications.The primary morphologies of COFs for tumors treatment can be categorized into four types:nanospheres,nanosheets,nano-rods/tubes and nanoparticles.Furthermore,we review recent research articles and systematically discuss recent advancements in COFs for chemotherapy,chemodynamic therapy,photodynamic therapy,photothermal therapy and combination therapy.In conclusion,we outline the current obstacles and potential future directions for this distinctive research area.
基金the financial support provided by the National Natural Science Foundation of China(No.52175413)the Natural Science Foundation of Jiangsu Province(No.BK20192007)+3 种基金the National Natural Science Foundation of China for Creative Research Groups(No.51921003)the Fundamental Research Funds for the Central Universities(No.NS2021034)the Aeronautical Science Foundation of China(No.201907052002)the Interdisciplinary Innovation Fund for Doctoral Students of Nanjing University of Aeronautics and Astronautics(No.KXKCXJJ202207).
文摘Wire electrochemical machining(WECM) is a flexible and effective method for machining complex-shaped metal components, but the ability to machine large-thickness workpieces is hampered by the difficulty of transporting electrolytic products in the narrow machining gap. This paper proposes a novel hybrid machining technique that combines the characteristics of WECM and wire electric discharge machining(WEDM), namely, helical wire electrochemical discharge machining. The formation mechanism of electrical discharge in salt-glycol solution was elucidated.Experiments and simulation were conducted to verify the machining mechanism and investigate the performance of the proposed technique. The results show that as the recast layer can be removed by electrochemical action during the proposed process, the surface quality is effectively improved.Minimum surface roughness of the slit sidewall after machining reaches Ra= 0.12 μm. Minimum standard deviation of the slit after machining reaches 5 μm. Moreover, the existence of the discharges significantly improves the transport of the electrolytic products, thus ensuring high machining efficiency. In the experiments, the maximum feed rate of the helical wire electrochemical discharge machining reaches 7 μm/s(12.6 mm^(2)/min). Finally, mortise structures of Inconel 718 with good machining accuracy and surface quality are fabricated with a feed rate of 5 μm/s(9 mm^(2)/min),demonstrating that electrical discharge assisted helical wire ECM is a promising technique for machining large-thickness hard metal materials.
基金Natural Science Foundation of Xinjiang,Grant/Award Number:2022D01E03West Light Foundation of the Chinese Academy of Sciences,Grant/Award Number:2021-XBQNXZ-023+1 种基金National Natural Science Foundation of China,Grant/Award Numbers:52172168,22104152Key Research Program of Frontier Sciences,CAS,。
文摘The precise regulation of interactions provided by aggregation-induced emission(AIE)probes is of considerable significance for improving the sensing performance in the field of on-site detection.Here,a highly sensitive perchlorate detection probe was designed by precisely modulating the van der Waals interactions by adjusting the length of the alkyl chain.The optimized AIE probe demonstrated superior perchlorate detection performance owing to its strong van der Waals interactions with perchlorate,including a low detection limit(53.81 nM),rapid response(<5 s),and excellent specificity even in the presence of 16 interfering anions.In addition,a hydrogel-based device loaded with the probe was constructed to achieve ultrasensitive recognition of perchlorate particles with a detection limit as low as 15 fg under a fluorescence microscope.Moreover,the practicality of the probe was further verified by employing a sensing chip in a portable detector,and thus the probe has been proven to be highly promising for trace perchlorate monitoring in real scenarios.We expect the present study to be of great value for the efficient design of high-performance fluorescent probes.
基金Tianchi Doctoral Program(51052300573,51052401541)National Natural Science Foundation of China(22275206)+4 种基金China Postdoctoral Science Foundation(2022M712326)Key Technologies R&D Program of Henan(232102231038)Major Science and Technology Project of Xinjiang(2022A01006-3)Science Foundation for Outstanding Young People of Xinjiang(2022D01E40)Youth Science Foundation of Xinjiang(2022D01C69).
文摘Flexible quantum dot light-emitting diodes(QLEDs)show great promise for the next generation of flexible,wearable,and artificial intelligence display applications.However,the performance of flexible QLEDs still lags behind that of rigid substrate devices,hindering their commercialization for display applications.Here we report the superior performance of flexible QLEDs based on efficient red ZnCdSe/ZnS/ZnSe QDs(A-QDs)with antitype-I nanostructures.We reveal that using ZnS as an intermediate shell can effectively confine the exciton wavefunction to the inner core,reducing the surface sensitivity of the QDs and maintaining its excellent emission properties.These flexible QLEDs exhibit a peak external quantum efficiency of 23.0%and a long lifetime of 63,050 h,respectively.The anti-type-I nanostructure of A-QDs in the device simultaneously suppresses defectinduced nonradiative recombination and balances carrier injection,achieving the most excellent performance of flexible QLEDs ever reported.This study provides new insights into achieving superior performance in flexible QD-based electroluminescent devices.
