ZnO doped Pt/CeO2 nanocomposites were prepared by electrospinning and reduction impregnation.Xray diffraction（XRD）,transmission electron microscopy（TEM）,energy disperse spectroscopy（EDS） and X-ray photoelectron ...ZnO doped Pt/CeO2 nanocomposites were prepared by electrospinning and reduction impregnation.Xray diffraction（XRD）,transmission electron microscopy（TEM）,energy disperse spectroscopy（EDS） and X-ray photoelectron spectroscopy（XPS） were employed to characterize the nanocomposites.It is observed that ZnO and CeO2 form the hexagonal wurtzite phase and cubic fluorite phase in the nanocomposite,respectively,whilst Pt nanoparticles（NPs） with the number-averaged size of ca.3.1 nm are uniformly distributed on the surface of nanofibers.The mass fraction of Pt NPs in the nanocomposites is about 10 wt%.The doping of ZnO is effective to promote reactive oxygen species,surface reaction sites and the interaction between Pt and oxides.The catalytic performance of nanocomposites was evaluated by the methanol electro-oxidation.indexed with the catalytic activity,stability of catalyst.As a result,it is found that the nanocomposite exhibits much higher activity and stability for methanol oxidation than the undoped Pt/CeO2 catalyst.展开更多
The uniform cauliflower-like ZnO films were deposited on the conducting substrate by a chemical bath deposition in urea/water solution. The film structure and morphology were characterized by X-ray diffraction, thermo...The uniform cauliflower-like ZnO films were deposited on the conducting substrate by a chemical bath deposition in urea/water solution. The film structure and morphology were characterized by X-ray diffraction, thermo- gravimetric differential thermal analysis, energy dispersive spectroscopy, selected area electron diffraction, field emission scanning electron microscopy and high resolution transmission electron microscopy. The average diameter of ZnO nanoparticles and the petal thickness were 25 nm and 8 μm, respectively. Dye- sensitized solar cells based on the cauliflower-like ZnO film electrode showed the short-circuit current density of 6.08 mA/cm2, the open-circuit photovoltage of 0.66 V, the fill factor of 0.55 and the overall conversion efficiency of 2.18%. The equivalent circuit of cells based on the ZnO film electrodes was measured by the electrochemical impedance spectroscopy. Furthermore, the analysis of equivalent circuit provided the relationship between the cell performance and the interracial resistance, such as the shunt resistance and the series resistance.展开更多
This paper mainly investigates the semicontinuity of solution mappings for set optimization problems under a partial order set relation instead of upper and lower set less order relations. To this end, we propose two ...This paper mainly investigates the semicontinuity of solution mappings for set optimization problems under a partial order set relation instead of upper and lower set less order relations. To this end, we propose two types of monotonicity definition for the set-valued mapping introduced by two nonlinear scalarization functions which are presented by these partial order relations. Then, we give some sufficient conditions for the semicontinuity and closedness of solution mappings for parametric set optimization problems. The results presented in this paper are new and extend the main results given by some authors in the literature.展开更多
Excessive fructose diet is closely associated with colorectal cancer(CRC)progression.Nevertheless,fructose’s specific function and precise mechanism in colorectal cancer liver metastasis(CRLM)is rarely known.Here,thi...Excessive fructose diet is closely associated with colorectal cancer(CRC)progression.Nevertheless,fructose’s specific function and precise mechanism in colorectal cancer liver metastasis(CRLM)is rarely known.Here,this study reported that the fructose absorbed by primary colorectal cancer could accelerate CRLM,and the expression of KHK-A,not KHK-C,in liver metastasis was higher than in paired primary tumors.Furthermore,KHK-A facilitated fructose-dependent CRLM in vitro and in vivo by phosphorylating PKM2 at Ser37.PKM2 phosphorylated by KHK-A inhibited its tetramer formation and pyruvic acid kinase activity but promoted the nuclear accumulation of PKM2.EMT and aerobic glycolysis activated by nuclear PKM2 enhance CRC cells’migration ability and anoikis resistance during CRLM progression.TEPP-46 treatment,targeting the phosphorylation of PKM2,inhibited the pro-metastatic effect of KHK-A.Besides,c-myc activated by nuclear PKM2 promotes alternative splicing of KHK-A,forming a positive feedback loop.展开更多
REBCO tapes carry DC current under AC magnetic fields in proposed HTS fusion applications. AC loss will be generated in the process and it is important to understand the AC loss behaviour for safe operation of the fus...REBCO tapes carry DC current under AC magnetic fields in proposed HTS fusion applications. AC loss will be generated in the process and it is important to understand the AC loss behaviour for safe operation of the fusion magnets. In this work, magnetisation loss (Qm), dynamic resistance (Rdyn), and total loss (Qtotal) in four different REBCO tapes are numerically studied, using the measured and , for the magnetic field amplitude applied perpendicularly up to 8 T at 20 K and 50 K, where represents the magnetic field and field angle () dependent critical current density. The peak of Theva data is different from that of other tapes. We artificially shifted the ab-plane peak of Theva to the left by 25° to match the peak value. The newly shifted data is named as Theva-shift, which was also investigated to study the influence of the Theva peak shift on AC loss. The normalised DC transport current level (i = It/Ic0) ranges from 0.05 to 0.9, where the DC current amplitude and the self-critical current of the tape are represented by It and Ic0, respectively. The simulation results show that the AC losses deviate significantly from the Brandt-Indenbom (BI) equation at high magnetic fields. Jc and instantaneous loss curves for different tapes show correlation at high magnetic fields. The simulation results also show how different characteristics for different tapes influence AC losses. When AC loss values are scaled by the self-field critical current, Qm without current and Qtotal with current in the different tapes show a good agreement. It implies that the temperature dependence of the two types of loss can be calculated from a known loss at one temperature and the self-field critical current.展开更多
Serious freshwater shortage and environmental pollution boost the rapid development of solar-driven water production.Although improved evaporation rate has achieved in recent years,undesirable impurity(e.g.,pollutant ...Serious freshwater shortage and environmental pollution boost the rapid development of solar-driven water production.Although improved evaporation rate has achieved in recent years,undesirable impurity(e.g.,pollutant components)can also be inevitably evaporated and collected as impurity in produced freshwater.This work reports new ultra-light three-dimensional(3D)aerogels assembled by hierarchical Al_(2)O_(3)/TiO_(2) nanofibers and reduced graphene oxide(RGO)for excit-ing synchronized solar-driven evaporation and water purification.Hydrophilic Al_(2)O_(3)/TiO_(2) fibrous channels linked up the graphene hot-spots and water body for sufficient water supply and bulk water insulation.Meanwhile,featured with thermal insulation effect,the Al_(2)O_(3)/TiO_(2) nanofibers effectively locked the converted heat with less energy loss from sunlight.The introducing of Al_(2)O_(3)/TiO_(2) nanofibers into RGO aerogel led to the effective interfacial evaporation for a more rapid water evaporation rate(2.19 kg·m−2·h−1,normalized to evaporation area including both top and side surface),which was 36%higher than that of pristine RGO aerogel.Moreover,simultaneous with the strong steam generation,Al_(2)O_(3)/TiO_(2) nanofibers in situ removed the pollutants within steam by photodegradation,achieving polluted wastewater purification with high con-taminant removal ratio of 91.3%.Our work on coupling Al_(2)O_(3)/TiO_(2) nanofibers into photothermal aerogel provides attractive solutions for the challenges of clean water scarcity and serious environmental pollution.展开更多
PNP-type ligands showed very good property in the catalytic systems of PNP/Cr(Ⅲ)/methylaluminoxane(MAO)for ethylene selective tetramerization toward1-octene.In this research,two PNP analogues bis(diphenylphosphino)ph...PNP-type ligands showed very good property in the catalytic systems of PNP/Cr(Ⅲ)/methylaluminoxane(MAO)for ethylene selective tetramerization toward1-octene.In this research,two PNP analogues bis(diphenylphosphino)phenylborane and bis(diphenylphosphino)dimethylsilane have been synthesized and characterized.In combination with CrCl3(THF)3as active center and MAO as cocatalyst,these ligands produced a new catalytic systems for ethylene oligomerization to linear α-olefins with catalytic activities of up to 3.07 9 106g mol-1(cat)h-1.Herein,we report the effects of the reaction temperature,ethylene pressure,and the molar ratio of Al/Cr on the catalyst activities and product selectivities.展开更多
One-dimensional(1D)oxide nanofibers have attracted much attention in recent years but are still hampered by the difficulty in the expansion to 2D or 3D dimensions.Herein,ultrathin CeO_(2)/SiO_(2)nanofibers with intrig...One-dimensional(1D)oxide nanofibers have attracted much attention in recent years but are still hampered by the difficulty in the expansion to 2D or 3D dimensions.Herein,ultrathin CeO_(2)/SiO_(2)nanofibers with intriguing core-sheath structures were simply fabricated by a facile single-spinneret electrospinning method and were subsequently integrated as 2D nanofi-brous mats and 3D sponges.Introducing secondary oxide(i.e.,SiO_(2))could induce a unique fine structure and further inhibit the sintering of CeO_(2)nanocrystals,endowing the resultant dual-oxide nanofibers with high porosity,good flexibility,and enriched oxygen defects.Benefiting from the core-sheath structure and dual-oxide component,the CeO_(2)/SiO_(2)nanofibers could stabilize 2.59 nm-Pt clusters against sintering at 600℃.Once assembled into a 2D mat,the nanofibers could efficiently decrease the soot oxidation temperature by 63℃.Moreover,the core-sheath CeO_(2)/SiO_(2)nanofibers can be readily integrated with graphene nanosheets into a 3D sponge via a gas foaming protocol,showing 218.5 mg/g of adsorption capacity toward Rhodamine B molecules.This work shed lights on the versatile applications of oxide nanofibers toward clean energy ultili-zation and low-carbon development.展开更多
Purpose Colorectal cancer is a common malignant tumor worldwide.In China,the ratio of rectal cancer to coloncancer in terms of incidence is close to 1:1.Low rectal cancer accounts for more than half of all cases of re...Purpose Colorectal cancer is a common malignant tumor worldwide.In China,the ratio of rectal cancer to coloncancer in terms of incidence is close to 1:1.Low rectal cancer accounts for more than half of all cases of rectal cancer.In recent years,the proportion of rectal cancer has trended downward,however the incidence of rectal cancer inyounger adults is increasing.The CACA Guidelines for Holistic Integrative Management of Rectal Cancer were editedto help improve the diagnosis and comprehensive treatment in China.Methods This guideline has been prepared by consensuses reached by the CACA Committee of Colorectal CancerSociety,based on a careful review of the latest evidence including China’s studies,and referred to domestic and internationalrelative guidelines,also considered China’s specific national conditions and clinical practice.Results The CACA Guidelines for Holistic Integrative Management of Rectal Cancer include the epidemiology of rectalcancer,prevention and screening,diagnosis,treatment of nonmetastatic and metastatic rectal cancer,follow-up,and whole-course rehabilitation management.Conclusion Committee of Colorectal Cancer Society,Chinese Anti-Cancer Association,standardizes the diagnosisand treatment of rectal cancer in China through the formulation of the CACA Guidelines.展开更多
The human digestive tract is home to trillions of microbes,and owing to the advent of next-generation sequencing at the turn of the century and the development of bioinformatics technology,researchers have been able t...The human digestive tract is home to trillions of microbes,and owing to the advent of next-generation sequencing at the turn of the century and the development of bioinformatics technology,researchers have been able to unravel the picture of the gut microbiome(1).展开更多
Light has been sought and explored by human since ancient times.As the most important form of light,fluorescence is significant to applications in bioimaging and optoelectronic devices.However,fluorescence quenching p...Light has been sought and explored by human since ancient times.As the most important form of light,fluorescence is significant to applications in bioimaging and optoelectronic devices.However,fluorescence quenching problem constitutes a serious bottleneck in materials creation.Inspired from the core–shell structure in nature,we report an effective strategy to overcome this long-standing problem by utilizing a molecular core–shell structure.With an emissive core and multifunctional shell fragments,these compounds show aggregation-induced delayed fluorescence(AIDF)properties by restricting singlet oxygen(^(1)O_(2))generation and suppressing the triplet–triplet annihilation(TTA).Protected by the functional shell,the aggregation-induced emission luminogens(AIEgens)exhibit strong emission with high photoluminescent quantum yield and exciton utilization.Furthermore,because the shell materials can form exciplex with electron-transport materials,the fully solution-processed organic light-emitting diodes(OLEDs)based on these core–shell materials show low turnon voltages,excellent device performance with current efficiency of 61.4 cd A–1 and power efficiency of 42.8 lm W–1,which is a record-breaking efficiency based on all-solution processed organic multilayer systems among the AIE-OLEDs so far.This simple visualization strategy based on molecular core–shell structure provides a promising platform for AIEgens used in the fully wet-processed optoelectronic field.展开更多
Photoelectrochemical(PEC)nanomaterials are critical to producing clean oxygenation or value-added chemical production by utilizing sustainable solar energy,but are always limited by simultaneous integration of archite...Photoelectrochemical(PEC)nanomaterials are critical to producing clean oxygenation or value-added chemical production by utilizing sustainable solar energy,but are always limited by simultaneous integration of architectural engineering and electronic regulation in one structure.Directed by density functional theory(DFT)calculations and finite element analysis(FEA),the bioinspired ivy-like Fe_(2)O_(3)heterostructures with enriched oxygen defects on TiO_(2)nanofibers are designed for boosting PEC performances.Ivy-like Fe_(2)O_(3)photo-sheets remarkably enhanced the light harvesting by multiple light-mater interactions.The oxygen vacancies on Fe_(2)O_(3)photo-sheets could aid the photons catching and promote the reactivity at active sites.More importantly,demonstrated by a well-designed dynamic observation,the abundant tip-edges within ivy-like Fe_(2)O_(3)photo-sheets enabled the surface of heterostructure with hydrophilic and aerophobic properties.The functionalized surface allowed the rapid desorption of produced bubbles and thus ensured a high density of unoccupied active sites for electrolyte accessing.Featured by these attributes,the Fe_(2)O_(3)@TiO_(2)nanofibers delivered an excellent photocurrent of 40.8 mA/mg,high donor density(1.2×10^(18)cm^(−3)),and rapid oxygen production rate(1 mmol/(L∙h)).This work demonstrates a new strategy on nano-structural design for enhancing light-harvesting and making a hydrophilic/aerophobic surface on low-dimensional oxide nanomaterial,holding great potential on designing high-performance PEC devices for producing survival source gas,carbon-neutral fuel,and valuedchemicals.展开更多
AC loss is one of the greatest obstacles for high‐temperature superconducting(HTS)applications.In some HTS applications,coated conductors carry non‐sinusoidal currents.Thus,it is important to investigate the effect ...AC loss is one of the greatest obstacles for high‐temperature superconducting(HTS)applications.In some HTS applications,coated conductors carry non‐sinusoidal currents.Thus,it is important to investigate the effect of various waveforms on AC loss in coated conductors.In this work,transport AC loss in a 4 mm‐wide REBCO coated conductor carrying sinusoidal and non‐sinusoidal currents,is numerically investigated.The current amplitudes,the frequency of the transport current,and n‐value are varied.Non‐sinusoidal transport current waveforms studied include square,five types of trapezoidal,and triangular waveforms.Simulated results show that,for a given current amplitude,AC loss for the square current waveform is the greatest,that for the triangular waveform is the smallest.The sequence of AC loss in the conductor for different current waveforms coincides with the penetration depth,which implies the penetration depth determines the AC loss of the coated conductor.Furthermore,the transport AC loss in the conductor was found to decrease with frequency as f2=n for non‐sinusoidal transport current.展开更多
基金Project supported by the National Natural Science Foundation of China(21475021,21427807)the Natural Science Foundation of Jiangsu Province(BK20141331)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘ZnO doped Pt/CeO2 nanocomposites were prepared by electrospinning and reduction impregnation.Xray diffraction（XRD）,transmission electron microscopy（TEM）,energy disperse spectroscopy（EDS） and X-ray photoelectron spectroscopy（XPS） were employed to characterize the nanocomposites.It is observed that ZnO and CeO2 form the hexagonal wurtzite phase and cubic fluorite phase in the nanocomposite,respectively,whilst Pt nanoparticles（NPs） with the number-averaged size of ca.3.1 nm are uniformly distributed on the surface of nanofibers.The mass fraction of Pt NPs in the nanocomposites is about 10 wt%.The doping of ZnO is effective to promote reactive oxygen species,surface reaction sites and the interaction between Pt and oxides.The catalytic performance of nanocomposites was evaluated by the methanol electro-oxidation.indexed with the catalytic activity,stability of catalyst.As a result,it is found that the nanocomposite exhibits much higher activity and stability for methanol oxidation than the undoped Pt/CeO2 catalyst.
基金support of the National Basic Research Program of China (973 Program,No.2013CB932902)the National Natural Science Foundation of China (No. 21173042)+3 种基金the National Natural Science Foundation of Jiangsu (No. BK201123694)the National Natural Science Foundation of Hebei (No.B2012402006)the Jiangsu Key Laboratory of Environmental Material and Environmental Engineering (No.JHCG201012)the Foundation of Southeast of University (Nos.3212001102 and 3212002205)
文摘The uniform cauliflower-like ZnO films were deposited on the conducting substrate by a chemical bath deposition in urea/water solution. The film structure and morphology were characterized by X-ray diffraction, thermo- gravimetric differential thermal analysis, energy dispersive spectroscopy, selected area electron diffraction, field emission scanning electron microscopy and high resolution transmission electron microscopy. The average diameter of ZnO nanoparticles and the petal thickness were 25 nm and 8 μm, respectively. Dye- sensitized solar cells based on the cauliflower-like ZnO film electrode showed the short-circuit current density of 6.08 mA/cm2, the open-circuit photovoltage of 0.66 V, the fill factor of 0.55 and the overall conversion efficiency of 2.18%. The equivalent circuit of cells based on the ZnO film electrodes was measured by the electrochemical impedance spectroscopy. Furthermore, the analysis of equivalent circuit provided the relationship between the cell performance and the interracial resistance, such as the shunt resistance and the series resistance.
文摘This paper mainly investigates the semicontinuity of solution mappings for set optimization problems under a partial order set relation instead of upper and lower set less order relations. To this end, we propose two types of monotonicity definition for the set-valued mapping introduced by two nonlinear scalarization functions which are presented by these partial order relations. Then, we give some sufficient conditions for the semicontinuity and closedness of solution mappings for parametric set optimization problems. The results presented in this paper are new and extend the main results given by some authors in the literature.
基金funded by the National Natural Science Foundation(Grant Number 82273406)Basic Research Program of Jiangsu Province(Grant No.BK20201491,China)+2 种基金Nature Key Research and Development Program of Jiangsu Province(BE2021742,China)Jiangsu Province Capability Improvement Project through Science,Technology and Education(Jiangsu Provincial Medical Key Discipline,ZDXK202222,China)the National Natural Science Foundation(Grant Number 82203656,China).
文摘Excessive fructose diet is closely associated with colorectal cancer(CRC)progression.Nevertheless,fructose’s specific function and precise mechanism in colorectal cancer liver metastasis(CRLM)is rarely known.Here,this study reported that the fructose absorbed by primary colorectal cancer could accelerate CRLM,and the expression of KHK-A,not KHK-C,in liver metastasis was higher than in paired primary tumors.Furthermore,KHK-A facilitated fructose-dependent CRLM in vitro and in vivo by phosphorylating PKM2 at Ser37.PKM2 phosphorylated by KHK-A inhibited its tetramer formation and pyruvic acid kinase activity but promoted the nuclear accumulation of PKM2.EMT and aerobic glycolysis activated by nuclear PKM2 enhance CRC cells’migration ability and anoikis resistance during CRLM progression.TEPP-46 treatment,targeting the phosphorylation of PKM2,inhibited the pro-metastatic effect of KHK-A.Besides,c-myc activated by nuclear PKM2 promotes alternative splicing of KHK-A,forming a positive feedback loop.
基金NZ Royal Society Marsden under Grant MFP-VUW2205New Zealand Ministry of Business,Innovation and Employment under the Advanced Energy Technology Platform program“High power electric motors for large scale transport”under Grant RTVU2004.
文摘REBCO tapes carry DC current under AC magnetic fields in proposed HTS fusion applications. AC loss will be generated in the process and it is important to understand the AC loss behaviour for safe operation of the fusion magnets. In this work, magnetisation loss (Qm), dynamic resistance (Rdyn), and total loss (Qtotal) in four different REBCO tapes are numerically studied, using the measured and , for the magnetic field amplitude applied perpendicularly up to 8 T at 20 K and 50 K, where represents the magnetic field and field angle () dependent critical current density. The peak of Theva data is different from that of other tapes. We artificially shifted the ab-plane peak of Theva to the left by 25° to match the peak value. The newly shifted data is named as Theva-shift, which was also investigated to study the influence of the Theva peak shift on AC loss. The normalised DC transport current level (i = It/Ic0) ranges from 0.05 to 0.9, where the DC current amplitude and the self-critical current of the tape are represented by It and Ic0, respectively. The simulation results show that the AC losses deviate significantly from the Brandt-Indenbom (BI) equation at high magnetic fields. Jc and instantaneous loss curves for different tapes show correlation at high magnetic fields. The simulation results also show how different characteristics for different tapes influence AC losses. When AC loss values are scaled by the self-field critical current, Qm without current and Qtotal with current in the different tapes show a good agreement. It implies that the temperature dependence of the two types of loss can be calculated from a known loss at one temperature and the self-field critical current.
基金This work was financially supported by the National Natural Science Foundation of China(21975042)Natural Science Foundation of Jiangsu Province(BK20171153)+3 种基金the Project of Six Talents Climax Foundation of Jiangsu(XCL-082)the Equipment Pre-research Fund of National Defence Science and Technology Key Laboratory(614220504030817)the Fundamental Research Funds for the Central Universitiesthe Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Serious freshwater shortage and environmental pollution boost the rapid development of solar-driven water production.Although improved evaporation rate has achieved in recent years,undesirable impurity(e.g.,pollutant components)can also be inevitably evaporated and collected as impurity in produced freshwater.This work reports new ultra-light three-dimensional(3D)aerogels assembled by hierarchical Al_(2)O_(3)/TiO_(2) nanofibers and reduced graphene oxide(RGO)for excit-ing synchronized solar-driven evaporation and water purification.Hydrophilic Al_(2)O_(3)/TiO_(2) fibrous channels linked up the graphene hot-spots and water body for sufficient water supply and bulk water insulation.Meanwhile,featured with thermal insulation effect,the Al_(2)O_(3)/TiO_(2) nanofibers effectively locked the converted heat with less energy loss from sunlight.The introducing of Al_(2)O_(3)/TiO_(2) nanofibers into RGO aerogel led to the effective interfacial evaporation for a more rapid water evaporation rate(2.19 kg·m−2·h−1,normalized to evaporation area including both top and side surface),which was 36%higher than that of pristine RGO aerogel.Moreover,simultaneous with the strong steam generation,Al_(2)O_(3)/TiO_(2) nanofibers in situ removed the pollutants within steam by photodegradation,achieving polluted wastewater purification with high con-taminant removal ratio of 91.3%.Our work on coupling Al_(2)O_(3)/TiO_(2) nanofibers into photothermal aerogel provides attractive solutions for the challenges of clean water scarcity and serious environmental pollution.
基金supported by the National Natural Science Foundation of China (U1162114,U1362110)the Program for New Century Excellent Talents in University (NCET-070142)
文摘PNP-type ligands showed very good property in the catalytic systems of PNP/Cr(Ⅲ)/methylaluminoxane(MAO)for ethylene selective tetramerization toward1-octene.In this research,two PNP analogues bis(diphenylphosphino)phenylborane and bis(diphenylphosphino)dimethylsilane have been synthesized and characterized.In combination with CrCl3(THF)3as active center and MAO as cocatalyst,these ligands produced a new catalytic systems for ethylene oligomerization to linear α-olefins with catalytic activities of up to 3.07 9 106g mol-1(cat)h-1.Herein,we report the effects of the reaction temperature,ethylene pressure,and the molar ratio of Al/Cr on the catalyst activities and product selectivities.
基金This work was financially supported by the Natural Science Foundation of China(21975042)the Project of Six Talents Climax Foundation of Jiangsu(XCL-082)+3 种基金Innovation Platform Project Supported by Jiangsu Province(6907041203)the Young Talent Lifting Project of Jiangsu Science and Technology Associate,the Fundamental Research Funds for the Central Universities,the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX22_0261)the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe open project of State Key Laboratory of Physical Chemistry of Solid Surfaces in Xiamen University.
文摘One-dimensional(1D)oxide nanofibers have attracted much attention in recent years but are still hampered by the difficulty in the expansion to 2D or 3D dimensions.Herein,ultrathin CeO_(2)/SiO_(2)nanofibers with intriguing core-sheath structures were simply fabricated by a facile single-spinneret electrospinning method and were subsequently integrated as 2D nanofi-brous mats and 3D sponges.Introducing secondary oxide(i.e.,SiO_(2))could induce a unique fine structure and further inhibit the sintering of CeO_(2)nanocrystals,endowing the resultant dual-oxide nanofibers with high porosity,good flexibility,and enriched oxygen defects.Benefiting from the core-sheath structure and dual-oxide component,the CeO_(2)/SiO_(2)nanofibers could stabilize 2.59 nm-Pt clusters against sintering at 600℃.Once assembled into a 2D mat,the nanofibers could efficiently decrease the soot oxidation temperature by 63℃.Moreover,the core-sheath CeO_(2)/SiO_(2)nanofibers can be readily integrated with graphene nanosheets into a 3D sponge via a gas foaming protocol,showing 218.5 mg/g of adsorption capacity toward Rhodamine B molecules.This work shed lights on the versatile applications of oxide nanofibers toward clean energy ultili-zation and low-carbon development.
文摘Purpose Colorectal cancer is a common malignant tumor worldwide.In China,the ratio of rectal cancer to coloncancer in terms of incidence is close to 1:1.Low rectal cancer accounts for more than half of all cases of rectal cancer.In recent years,the proportion of rectal cancer has trended downward,however the incidence of rectal cancer inyounger adults is increasing.The CACA Guidelines for Holistic Integrative Management of Rectal Cancer were editedto help improve the diagnosis and comprehensive treatment in China.Methods This guideline has been prepared by consensuses reached by the CACA Committee of Colorectal CancerSociety,based on a careful review of the latest evidence including China’s studies,and referred to domestic and internationalrelative guidelines,also considered China’s specific national conditions and clinical practice.Results The CACA Guidelines for Holistic Integrative Management of Rectal Cancer include the epidemiology of rectalcancer,prevention and screening,diagnosis,treatment of nonmetastatic and metastatic rectal cancer,follow-up,and whole-course rehabilitation management.Conclusion Committee of Colorectal Cancer Society,Chinese Anti-Cancer Association,standardizes the diagnosisand treatment of rectal cancer in China through the formulation of the CACA Guidelines.
基金This study was supported by grants from the National Natural Science Foundation of China(No.82273406)the Natural Science Foundation of Jiangsu Province(No.BK20211378).
文摘The human digestive tract is home to trillions of microbes,and owing to the advent of next-generation sequencing at the turn of the century and the development of bioinformatics technology,researchers have been able to unravel the picture of the gut microbiome(1).
基金National Natural Science Foundation of China,Grant/Award Numbers:21875036,22135004Open Fund of theKeyLab of Organic Optoelec-tronics&Molecular EngineeringInnovation and Technology Commission,Grant/Award Number:ITC-CNERC14SC01。
文摘Light has been sought and explored by human since ancient times.As the most important form of light,fluorescence is significant to applications in bioimaging and optoelectronic devices.However,fluorescence quenching problem constitutes a serious bottleneck in materials creation.Inspired from the core–shell structure in nature,we report an effective strategy to overcome this long-standing problem by utilizing a molecular core–shell structure.With an emissive core and multifunctional shell fragments,these compounds show aggregation-induced delayed fluorescence(AIDF)properties by restricting singlet oxygen(^(1)O_(2))generation and suppressing the triplet–triplet annihilation(TTA).Protected by the functional shell,the aggregation-induced emission luminogens(AIEgens)exhibit strong emission with high photoluminescent quantum yield and exciton utilization.Furthermore,because the shell materials can form exciplex with electron-transport materials,the fully solution-processed organic light-emitting diodes(OLEDs)based on these core–shell materials show low turnon voltages,excellent device performance with current efficiency of 61.4 cd A–1 and power efficiency of 42.8 lm W–1,which is a record-breaking efficiency based on all-solution processed organic multilayer systems among the AIE-OLEDs so far.This simple visualization strategy based on molecular core–shell structure provides a promising platform for AIEgens used in the fully wet-processed optoelectronic field.
基金supported by the National Natural Science Foundation of China(No.21975042)the Project of Six Talents Climax Foundation of Jiangsu(No.XCL-082)+1 种基金the Innovation Platform Project Supported by Jiangsu Province(No.6907041203)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Photoelectrochemical(PEC)nanomaterials are critical to producing clean oxygenation or value-added chemical production by utilizing sustainable solar energy,but are always limited by simultaneous integration of architectural engineering and electronic regulation in one structure.Directed by density functional theory(DFT)calculations and finite element analysis(FEA),the bioinspired ivy-like Fe_(2)O_(3)heterostructures with enriched oxygen defects on TiO_(2)nanofibers are designed for boosting PEC performances.Ivy-like Fe_(2)O_(3)photo-sheets remarkably enhanced the light harvesting by multiple light-mater interactions.The oxygen vacancies on Fe_(2)O_(3)photo-sheets could aid the photons catching and promote the reactivity at active sites.More importantly,demonstrated by a well-designed dynamic observation,the abundant tip-edges within ivy-like Fe_(2)O_(3)photo-sheets enabled the surface of heterostructure with hydrophilic and aerophobic properties.The functionalized surface allowed the rapid desorption of produced bubbles and thus ensured a high density of unoccupied active sites for electrolyte accessing.Featured by these attributes,the Fe_(2)O_(3)@TiO_(2)nanofibers delivered an excellent photocurrent of 40.8 mA/mg,high donor density(1.2×10^(18)cm^(−3)),and rapid oxygen production rate(1 mmol/(L∙h)).This work demonstrates a new strategy on nano-structural design for enhancing light-harvesting and making a hydrophilic/aerophobic surface on low-dimensional oxide nanomaterial,holding great potential on designing high-performance PEC devices for producing survival source gas,carbon-neutral fuel,and valuedchemicals.
基金supported by the New Zealand Ministry of Business,Innovation and Employment under Catalyst Space and Fusion project“International Science Co‐operation on Superconductor Technologies”contract number RTVU1916supported by the New Zealand Ministry of Business,Innovation and Employment under the Advanced Energy Technology Platform program“High power electric motors for large scale transport”contract number RTVU2004.
文摘AC loss is one of the greatest obstacles for high‐temperature superconducting(HTS)applications.In some HTS applications,coated conductors carry non‐sinusoidal currents.Thus,it is important to investigate the effect of various waveforms on AC loss in coated conductors.In this work,transport AC loss in a 4 mm‐wide REBCO coated conductor carrying sinusoidal and non‐sinusoidal currents,is numerically investigated.The current amplitudes,the frequency of the transport current,and n‐value are varied.Non‐sinusoidal transport current waveforms studied include square,five types of trapezoidal,and triangular waveforms.Simulated results show that,for a given current amplitude,AC loss for the square current waveform is the greatest,that for the triangular waveform is the smallest.The sequence of AC loss in the conductor for different current waveforms coincides with the penetration depth,which implies the penetration depth determines the AC loss of the coated conductor.Furthermore,the transport AC loss in the conductor was found to decrease with frequency as f2=n for non‐sinusoidal transport current.
