A refined reciprocating probe system was installed on the midplane of HL-2A tokamak. The system is developed in collaboration with the Institute of Scientific Instrument, Chinese Academy of Science in Shenyang.The sys...A refined reciprocating probe system was installed on the midplane of HL-2A tokamak. The system is developed in collaboration with the Institute of Scientific Instrument, Chinese Academy of Science in Shenyang.The system has been used to measure edge density, temperature, potential and their fluctuation profiles with 8 cm scan from scrapeoff layer to plasma boundary. The velocity of the reciprocating stroke is designed by 1 m ·s^-1.展开更多
A fast radial scanning probe system was constructed for the Keda Torus eXperiment(KTX)to measure the profiles of boundary plasma parameters such as floating potential,electron density,temperature,transport fluxes,etc....A fast radial scanning probe system was constructed for the Keda Torus eXperiment(KTX)to measure the profiles of boundary plasma parameters such as floating potential,electron density,temperature,transport fluxes,etc.The scanning probe system is driven by slow and fast motion mechanisms,corresponding to the stand-by movement of a stepping motor and the fast scanning movement of a high-torque servo-motor,respectively.In fast scanning,the scanner drives the probe radially up to 20 cm at a maximum velocity of 4.0 m s-1.A noncontact magnetic grating ruler with a high spatial resolution of 5μm is used for the displacement measurement.New scanning probe can reach the center of plasmas rapidly.The comparison of plasma floating potential profiles obtained by a fixed radial rake probe and the single scanning probe suggests that the high-speed scanning probe system is reliable for measuring edge plasma parameter profiles on the KTX device.展开更多
A multi-voltage probe array system is designed to measure the coupling resistance of an ion cyclotron resonance frequency antenna. In the process of the antenna coupling resistance data extraction, the minimization al...A multi-voltage probe array system is designed to measure the coupling resistance of an ion cyclotron resonance frequency antenna. In the process of the antenna coupling resistance data extraction, the minimization algorithm, the original Levenberg–Marquardt algorithm, is replaced by the Broyden–Fletcher–Goldfarb–Shanno algorithm to achieve more stable and accurate results. Moreover, a simple model of the multi-voltage probe array was applied to simulate the performance of the Kalman filter, and to optimize the distance and position of the probes and probe number to mitigate the influence of the system noise on the rebuilt results. During the EAST experiment in 2019, a four-voltage probe array was applied to measure the coupling resistance of line 6 during high confined mode discharge. The measurement results by the multivoltage probe array system and the voltage/current probe pair show a good agreement.展开更多
Enzyme assisted DNA probes are powerful tools in molecular diagnostics for their simplicity,rapidity,and low detection limit.However,cost of probes,difficulty in optimization and disturbance of secondary structure hin...Enzyme assisted DNA probes are powerful tools in molecular diagnostics for their simplicity,rapidity,and low detection limit.However,cost of probes,difficulty in optimization and disturbance of secondary structure hindered the wider application of enzyme assisted DNA probes.To solve the problems,we designed a new system named shared-probe system.By introducing two unlabeled single stranded DNA named Sh1 and Sh2 as the bridge between probe and the substrate,the same sequence of dually labeled probe with stable performance was shared for different mutations,thus sparing the expense and time cost on designing,synthesizing and optimizing corresponding probes.Besides,the hybridization between Sh1 and the substrate could overcome secondary structures,which guaranteed the detection of different substrates.The performance and generality of the design were tested by low abundance detection in synthetic single DNA samples and the limit of detection was 0.05%for PTENR130 Q,EGFR-L858 R and 0.02%for BRCA1-NM007294.3.In genomic DNA samples,the limit of detection of 0.1%can be achieved for EGFR-L858 R,demonstrating the potential of clinical application in our design.展开更多
In order to obtain creditable data an applicable method to optimize parameters of the Langmuir probes and circuits in a stationary laboratory device is investigated and an experimental criterion of the probe dimension...In order to obtain creditable data an applicable method to optimize parameters of the Langmuir probes and circuits in a stationary laboratory device is investigated and an experimental criterion of the probe dimension is developed. To obtain the electron temperature and density the Electron Energy Distribution Function （EEDF） approach with less computing time and more accurate results is applied, instead of the conventional slope approach. Moreover the influence of the vessel wall materials on the plasma density is discussed briefly, indicating that the dielectric wall is helpful to enhancing the electron density.展开更多
A newly designed divertor Langmuir probe diagnostic system has been installed in a rare closed divertor of the HL-2A tokamak and steadily operated for the study of divertor physics involved edge-localized mode mitigat...A newly designed divertor Langmuir probe diagnostic system has been installed in a rare closed divertor of the HL-2A tokamak and steadily operated for the study of divertor physics involved edge-localized mode mitigation,detachment and redistribution of heat flux,etc.Two sets of probe arrays including 274 probe tips were placed at two ports(approximately 180°separated toroidally),and the spatial and temporal resolutions of this measurement system could reach6 mm and 1μs,respectively.A novel design of the ceramic isolation ring can ensure reliable electrical insulation property between the graphite tip and the copper substrate plate where plasma impurities and the dust are deposited into the gaps for a long experimental time.Meanwhile,the condition monitoring and mode conversion between single and triple probe of the probe system could be conveniently implemented via a remote-control station.The preliminary experimental result shows that the divertor Langmuir probe system is capable of measuring the high spatiotemporal parameters involved the plasma density,electron temperature,particle flux as well as heat flux during the ELMy H-mode discharges.展开更多
Sulfydryl-contained(-SH)substances including hydrogen sulfide(H_(2)S),cysteine(Cys),homocysteine(Hcy)and glutathione(GSH)play crucial roles in living systems,and their variations are closely associated with various di...Sulfydryl-contained(-SH)substances including hydrogen sulfide(H_(2)S),cysteine(Cys),homocysteine(Hcy)and glutathione(GSH)play crucial roles in living systems,and their variations are closely associated with various diseases.Herein,we developed a near-infrared intramolecular charge transfer(ICT)based fluorescent probe Y-NBD,achieving detection of Cys/Hcy and H_(2)S with different fluorescent signals(green-red for Cys/Hcy,red for H_(2)S),large Stokes shifts(∼100/105nm or 191 nm)and high signal-background-ratio,but not responding to GSH.Y-NBD was successfully applied to image exogenous/endogenous Cys/Hcy and H_(2)S in various living cancer cells(HeLa,A549,and HepG2)and in zebrafish.It not only visualized the transformation pathway of several thiols in HepG2 cells but also verified that the intestine is the main site for the activation and metabolism of Y-NBD in zebrafish,as well as realized to evaluate the degree of drug-induced liver injury.This work provides a promising tool for imaging Cys/Hcy and H_(2)S in living systems and shows great potency in evaluating drug-induced liver injury and its treatment.展开更多
Conventional conductivity methods for measuring the void fraction in gas-liquid multiphase systems are typically affected by accuracy problems due to the presence of fluid flow and salinity.This study presents a novel...Conventional conductivity methods for measuring the void fraction in gas-liquid multiphase systems are typically affected by accuracy problems due to the presence of fluid flow and salinity.This study presents a novel approach for determining the void fraction based on a reciprocating dynamic conductivity probe used to measure the liquid film thickness under forced annular-flow conditions.The measurement system comprises a cyclone,a conductivity probe,a probe reciprocating device,and a data acquisition and processing system.This method ensures that the flow pattern is adjusted to a forced annular flow,thereby minimizing the influence of complex and variable gas-liquid flow patterns on the measurement results;Moreover,it determines the liquid film thickness solely according to circuit connectivity rather than specific conductivity values,thereby mitigating the impact of salinity.The reliability of the measurement system is demonstrated through laboratory experiments.The experimental results indicate that,in a range of gas phase superficial velocities 5–20 m/s and liquid phase superficial velocities 0.079–0.48 m/s,the maximum measurement deviation for the void fraction is 4.23%.展开更多
A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phospho...A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phosphorescence(RTP)properties,was prepared by doping 2,6-naphthalic acid(P)into matrix1at a low con-centration.P@1emitted a green RTP that was visible to the naked eye and lasted for approximately 2 s.P@1exhib-ited selective phosphorescence enhancement response towards Pb^(2+),with a detection limit of 2.52μmol·L^(-1).Themain detection mechanism is the Pb—O coordination-induced phosphorescence enhancement in the system.Inter-estingly,P@1also functioned as a dual-channel probe for the rapid detection of Fe^(3+)ions through fluorescencequenching with a detection limit of 0.038μmol·L^(-1).The recognition mechanism may be attributed to the competi-tive energy absorption betweenP@1and Fe^(3+)ions.CCDC:2388502,1.展开更多
To address the lack of systematic studies on heavy metal fluorescent probes in typical buffer solutions,this study developed a Fe^(3+)and Cu^(2+)fluorescent probe,DHU‑NP‑4,based on a naphthalimide fluorophore.Comparat...To address the lack of systematic studies on heavy metal fluorescent probes in typical buffer solutions,this study developed a Fe^(3+)and Cu^(2+)fluorescent probe,DHU‑NP‑4,based on a naphthalimide fluorophore.Comparative analysis of the probe's performance in various buffer systems revealed that buffers with high organic content are unsuitable for evaluating such probes.Furthermore,the pH of the solvent system was found to significantly influence the probe's behavior.Under highly acidic conditions(pH≤2),DHU‑NP‑4 exhibited exceptional specificity for Fe^(3+),while in alkaline conditions,it demonstrated high specificity for Cu^(2+).Leveraging these properties,the probe enabled the quantitative detection of Fe^(3+)and Cu^(2+)in solution.展开更多
Colorectal cancer(CRC)is one of the most prevalent malignant tumors worldwide,exhibiting high morbidity and mortality.Lack of efficient tools for early diagnosis and surgical resection guidance of CRC have been a seri...Colorectal cancer(CRC)is one of the most prevalent malignant tumors worldwide,exhibiting high morbidity and mortality.Lack of efficient tools for early diagnosis and surgical resection guidance of CRC have been a serious threat to the long-term survival rate of the CRC patients.Recent studies have shown that relative higher viscosity was presented in tumor cells compared to that in normal cells,leading to viscosity as a potential biomarker for CRC.Herein,we reported the development of a series of novel viscosity-sensitive and mitochondria-specific fluorescent probes(HTB,HTI,and HTP)for CRC detection.Among them,HTB showed high sensitivity,minimal background interference,low cytotoxicity,and significant viscous response capability,making it an ideal tool for distinguishing colorectal tumor cells from normal cells.Importantly,we have successfully utilized HTB to visualize in a CRC-cells-derived xenograft(CDX)model,enriching its medical imaging capacity,which laid a foundation for further clinical translational application.展开更多
Rheumatoid arthritis(RA) is a chronic inflammatory disease with multi-system damage and autoimmune features.The main clinical manifestations of RA include joint pain,swelling,and stiffness,and RA may lead to joint def...Rheumatoid arthritis(RA) is a chronic inflammatory disease with multi-system damage and autoimmune features.The main clinical manifestations of RA include joint pain,swelling,and stiffness,and RA may lead to joint deformity and dysfunction in severe cases.The pathologic development of RA involves complex interactions of multiple biomarkers,and detecting a single biomarker may produce falsepositive results due to other confounding factors.Therefore,fluorescent probes that can detect multiple biomarkers simultaneously are crucial for precise RA diagnosis.Peroxynitrite(ONOO^(-)) and viscosity are inflammation-related factors in cells.In this study,we developed a dual responsive near-infrared fluorescent probe,YLS,for ONOO^(-) and viscosity.The probe features dual-channel turn-on fluorescence responses at 625 and 760 nm upon the presence of ONOO^(-) and viscosity,respectively.Supported by YLS,we found that during RA pathology,lymphocyte infiltration not only increases the concentration of proteins in the joint fluid resulting in elevated viscosity;at the same time,the overproduction of ONOO^(-) exacerbates oxidative stress and inflammatory responses.This multiparameter assay is expected to improve the diagnostic accuracy of the early stages of RA,thus providing a scientific basis for early intervention and personalized treatment.展开更多
In this study,a self-calibrating near-infrared fluorescence probe was designed and synthesized based on the dual-fluorophore strategy utilizing methylene blue and coumarin.The probe utilized methylene blue(emission sp...In this study,a self-calibrating near-infrared fluorescence probe was designed and synthesized based on the dual-fluorophore strategy utilizing methylene blue and coumarin.The probe utilized methylene blue(emission spectrum range:640-740 nm)and coumarin fluorophore(emission spectrum range:440-600 nm)as signal output units,thereby achieving effective spectral separation and highly selective detection of HClO.Under physiological pH conditions,HClO triggers an oxidation-cleavage reaction,releasing methylene blue and coumarin,which emit distinct red and green fluorescence,respectively.This dual-emission feature enabled rapid HClO detection with two-channel detection limits of 25.13 nmol·L^(-1)(green channel)and 31.55 nmol·L^(-1)(red channel).Furthermore,in cell imaging experiments,this probe demonstrated excellent cell membrane permeability and low cytotoxicity,successfully enabling the monitoring of both endogenous and exogenous HClO in living cells.By incorporating a twochannel self-calibration system,the probe effectively mitigated signal variations caused by instrumental or environmental interference,substantially improving detection sensitivity and reliability.展开更多
This article provides a short review on the importance of the detailed analysis of a Langmuir probe I-V trace in a multi-Maxwellian plasma,and discuss proper procedures analyzing Langmuir probe I-V traces in bi-Maxwel...This article provides a short review on the importance of the detailed analysis of a Langmuir probe I-V trace in a multi-Maxwellian plasma,and discuss proper procedures analyzing Langmuir probe I-V traces in bi-Maxwellian and triple-Maxwellian Electron Energy Distribution Function(EEDF)plasmas.Discus⁃sion and demonstration of procedures include the treatment of the ion saturation current,electron saturation cur⁃rent,space-charge effects on the I-V trace,and most importantly how to properly isolate and fit for each electron group present in an I-V trace reflecting a mult-Maxwellian EEDF,as well as how having a multi-Maxwellian EEDF affects the procedures of treating the ion and electron saturation currents.Shortcomings of common improp⁃er procedures are discussed and demonstrated with simulated I-V traces to show how these procedures gives false measurements.展开更多
The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic s...The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic situation in the tumor.A fluorescence probe,AQD,with selective response toward hypoxia was designed for the detection of hypoxic tumor cells,which was obtained by the covalent connection of a large planar conjugated fluorophore with good fluorescence stability and a N,N-dimethylaniline moiety via the azo bond.The introduction of the azo bond in AQD caused significant fluorescence emission quenching,and the probe was reduced under hypoxic conditions to release the fluorophore via breaking the azo bond,resulting in the gradual recovery of fluorescence emission.Probe AQD exhibited a remarkable fluorescence response in hypoxic conditions,high selectivity,and good biocompatibility,which was successfully used for the imaging of hypoxic tumor cells and realized the detection of hypoxic A549 cells.展开更多
Herein,a luminescent europium-based metal-organic framework(Eu-MOF,[Eu_(3)(L)(HL)(NO_(3))_(2)(DMF)_(2)]·4DMF·5H_(2)O,H_(4)L=5,5′-(pyrazine-2,6-diyl)diisophthalic acid,DMF=N,N-dimethylformamide)was developed...Herein,a luminescent europium-based metal-organic framework(Eu-MOF,[Eu_(3)(L)(HL)(NO_(3))_(2)(DMF)_(2)]·4DMF·5H_(2)O,H_(4)L=5,5′-(pyrazine-2,6-diyl)diisophthalic acid,DMF=N,N-dimethylformamide)was developed for the dual-functional detection of environmental pollutants.This fluorescence-quenching-based sensor exhibited excep-tional sensitivity for both 2,4,6-trinitrophenol(TNP)and tetracycline(TC),achieving remarkably low detection lim-its of 1.96×10^(-6)and 1.71×10^(-7)mol·L^(-1),respectively.Notably,the system exhibited 99%fluorescence quenching ef-ficiency for TC,indicating ultra-efficient analyte recognition.The detection performance surpasses most reported lu-minescent MOF sensors,attributed to synergistic mechanisms of fluorescence resonance energy transfer(FRET)and photoinduced electron transfer(PET).CCDC:2446483.展开更多
Using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran(TCF)as a near-infrared fluorescent chromophore,we designed and synthesized a TCF-based fluorescent probe TCF-NS by introducing 2,4-dinitrophenyl ether ...Using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran(TCF)as a near-infrared fluorescent chromophore,we designed and synthesized a TCF-based fluorescent probe TCF-NS by introducing 2,4-dinitrophenyl ether as the recognized site for H_(2)S.The probe TCF-NS displayed a rapid-response fluorescent against H_(2)S with high sensitivity and selection but had no significant fluorescence response to other biothiols.Furthermore,TCF-NS was applied to sense H_(2)S in living cells successfully with minimized cytotoxicity and a large Stokes shift.展开更多
Butyrylcholinesterase(BChE)is a pivotal enzyme that degrades the neurotransmitter acetylcholine,which is related to learning and memory,into choline and acetic acid.BChE activity is strongly associated with various di...Butyrylcholinesterase(BChE)is a pivotal enzyme that degrades the neurotransmitter acetylcholine,which is related to learning and memory,into choline and acetic acid.BChE activity is strongly associated with various diseases,including Alzheimer’s disease,multiple sclerosis,diabetes,and lipid metabolism disorders.It also possesses pharmacological properties for combating cocaine addiction and detoxifying organophosphate poisoning.Given the significant importance of BChE in the biological and medical fields,detecting its activity and understanding its expression in the body are crucial for advancing related research.Herein,a brief review of recently reported specific fluorescence or chemiluminescence probes for quantifying and real-time monitoring BChE is provided.By utilizing unique recognition groups,these probes achieve highly selective identification of BChE and effectively resist interference from other biological factors.Probes demonstrate excellent performance in measuring BChE activity,screening BChE inhibitors,and locating BChE in cells and mice.These also offer strong technical support for early diagnosis,precise intervention,and effective treatment of diseases with pathological changes in BChE.展开更多
The overuse of surfactants has made them well-known environmental pollutants.So far,it is still a challenge to simultaneously distinguish cationic,anionic,zwitterionic,nonionic surfactants and surfactants with similar...The overuse of surfactants has made them well-known environmental pollutants.So far,it is still a challenge to simultaneously distinguish cationic,anionic,zwitterionic,nonionic surfactants and surfactants with similar structures based on traditional analytical techniques.We developed a high-throughput method for distinguishing various surfactants based on the adaptive emission profile as fingerprints(AEPF).The fluorescence response of the sensor was based on the interaction between surfactants and 1,3-diacetylpyrene(o-DAP)probe.The interaction affected the reversible conversion of free molecules and two aggregates in the solution,thereby changing the relative abundance and the fluorescence intensity ratio of two aggregates emitting different fluorescence.The o-DAP sensor can distinguish four types of surfactants(16 surfactants),especially surfactants of the same type with similar structures.The o-DAP sensor sensitively determined the critical micelle concentration(CMC)of 16 surfactants based on the interaction between o-DAP and surfactants.Additionally,the o-DAP sensor can detect and distinguish artificial vesicles made from different surfactants.展开更多
Excited-state intramolecular proton-transfer(ESIPT)based fluorescence probes are particularly attractive due to their unique properties including environmental sensitivity,a large Stokes shift,and potential for ratiom...Excited-state intramolecular proton-transfer(ESIPT)based fluorescence probes are particularly attractive due to their unique properties including environmental sensitivity,a large Stokes shift,and potential for ratiometric sensing.In general,ESIPT-based fluorophore incorporates an intramolecular hydrogen bonding interaction between a hydrogen bond donor(-OH and NH_(2)are common)and a hydrogen bond acceptor(C=N and C=O).More,protection-deprotection of hydroxyl group as hydrogen bond donor could induce an off-on switch of ESIPT-based emission.Therefore,protection-deprotection of hydroxyl group has been the widely used strategy to design fluorescent probes,where the potential key issue is selecting a protective group that can specifically leave in the presence of the target analyte.In this review,we mainly summarize the specific protecting groups(sites)and deprotection mechanisms for biologically important species(including reactive sulfur species(RSS),reactive oxygen species(ROS),enzymes,etc.),and analyze the advantages and disadvantages of different protection mechanisms from some aspects including probe stability,selectivity,response rate and assay system,etc.Based on the aforementioned,we further point out the current challenges and the potential future direction for developing ESIPT-based probes.展开更多
文摘A refined reciprocating probe system was installed on the midplane of HL-2A tokamak. The system is developed in collaboration with the Institute of Scientific Instrument, Chinese Academy of Science in Shenyang.The system has been used to measure edge density, temperature, potential and their fluctuation profiles with 8 cm scan from scrapeoff layer to plasma boundary. The velocity of the reciprocating stroke is designed by 1 m ·s^-1.
基金supported by the National Magnetic Confinement Fusion Science Program of China(No.2017YFE0301700)National Natural Science Foundation of China(No.11635008).
文摘A fast radial scanning probe system was constructed for the Keda Torus eXperiment(KTX)to measure the profiles of boundary plasma parameters such as floating potential,electron density,temperature,transport fluxes,etc.The scanning probe system is driven by slow and fast motion mechanisms,corresponding to the stand-by movement of a stepping motor and the fast scanning movement of a high-torque servo-motor,respectively.In fast scanning,the scanner drives the probe radially up to 20 cm at a maximum velocity of 4.0 m s-1.A noncontact magnetic grating ruler with a high spatial resolution of 5μm is used for the displacement measurement.New scanning probe can reach the center of plasmas rapidly.The comparison of plasma floating potential profiles obtained by a fixed radial rake probe and the single scanning probe suggests that the high-speed scanning probe system is reliable for measuring edge plasma parameter profiles on the KTX device.
基金China Fusion Engineering Experimental Reactor General Integration and Engineering Design (No. 2017YFE0300503)National Natural Science Foundation of China (No. 11775258)the Comprehensive Research Facility for Fusion Technology Program of China (No. 2018-000052-73-01-001228)。
文摘A multi-voltage probe array system is designed to measure the coupling resistance of an ion cyclotron resonance frequency antenna. In the process of the antenna coupling resistance data extraction, the minimization algorithm, the original Levenberg–Marquardt algorithm, is replaced by the Broyden–Fletcher–Goldfarb–Shanno algorithm to achieve more stable and accurate results. Moreover, a simple model of the multi-voltage probe array was applied to simulate the performance of the Kalman filter, and to optimize the distance and position of the probes and probe number to mitigate the influence of the system noise on the rebuilt results. During the EAST experiment in 2019, a four-voltage probe array was applied to measure the coupling resistance of line 6 during high confined mode discharge. The measurement results by the multivoltage probe array system and the voltage/current probe pair show a good agreement.
基金the National Natural Science Foundation of China(Nos.21705053 and 81871732)the Natural Science Foundation of Hubei Province(No.2017CFB117)+1 种基金Hubei Province Health and Family Planning Scientific Research Project(No.J2017Q017)Wuhan Youth Science and Technology Plan(No.2017050304010293)。
文摘Enzyme assisted DNA probes are powerful tools in molecular diagnostics for their simplicity,rapidity,and low detection limit.However,cost of probes,difficulty in optimization and disturbance of secondary structure hindered the wider application of enzyme assisted DNA probes.To solve the problems,we designed a new system named shared-probe system.By introducing two unlabeled single stranded DNA named Sh1 and Sh2 as the bridge between probe and the substrate,the same sequence of dually labeled probe with stable performance was shared for different mutations,thus sparing the expense and time cost on designing,synthesizing and optimizing corresponding probes.Besides,the hybridization between Sh1 and the substrate could overcome secondary structures,which guaranteed the detection of different substrates.The performance and generality of the design were tested by low abundance detection in synthetic single DNA samples and the limit of detection was 0.05%for PTENR130 Q,EGFR-L858 R and 0.02%for BRCA1-NM007294.3.In genomic DNA samples,the limit of detection of 0.1%can be achieved for EGFR-L858 R,demonstrating the potential of clinical application in our design.
文摘In order to obtain creditable data an applicable method to optimize parameters of the Langmuir probes and circuits in a stationary laboratory device is investigated and an experimental criterion of the probe dimension is developed. To obtain the electron temperature and density the Electron Energy Distribution Function （EEDF） approach with less computing time and more accurate results is applied, instead of the conventional slope approach. Moreover the influence of the vessel wall materials on the plasma density is discussed briefly, indicating that the dielectric wall is helpful to enhancing the electron density.
基金partially supported by National Natural Science Foundation of China(Nos.11875017,11875020,12175186 and 11905052)the National Magnetic Confinement Fusion Science Program of China(Nos.2019YFE03030002,2017YFE0301203 and 2018YFE0310100)the Sichuan Outstanding Youth Science Foundation(No.2020JDJQ0019)。
文摘A newly designed divertor Langmuir probe diagnostic system has been installed in a rare closed divertor of the HL-2A tokamak and steadily operated for the study of divertor physics involved edge-localized mode mitigation,detachment and redistribution of heat flux,etc.Two sets of probe arrays including 274 probe tips were placed at two ports(approximately 180°separated toroidally),and the spatial and temporal resolutions of this measurement system could reach6 mm and 1μs,respectively.A novel design of the ceramic isolation ring can ensure reliable electrical insulation property between the graphite tip and the copper substrate plate where plasma impurities and the dust are deposited into the gaps for a long experimental time.Meanwhile,the condition monitoring and mode conversion between single and triple probe of the probe system could be conveniently implemented via a remote-control station.The preliminary experimental result shows that the divertor Langmuir probe system is capable of measuring the high spatiotemporal parameters involved the plasma density,electron temperature,particle flux as well as heat flux during the ELMy H-mode discharges.
基金supported by the National Natural Science Foundation of China(Nos.22077099 and 22171223)the Innovation Capability Support Program of Shaanxi(Nos.2023-CX-TD-75 and 2022KJXX-32)+4 种基金the Technology Innovation Leading Program of Shaanxi(Program No.2023KXJ-209)the Natural Science Basic Research Program of Shaanxi(Nos.2022JQ-151 and 2023-JC-YB-141)Young Talent Fund of Association for Science and Technology in Shaanxi,China(No.SWYY202206)the Shaanxi Fundamental Science Research Project for Chemistry&Biology(Nos.22JHZ010 and 22JHQ080)the Yan’an City Science and Technology Project(No.2022SLZDCY-002).
文摘Sulfydryl-contained(-SH)substances including hydrogen sulfide(H_(2)S),cysteine(Cys),homocysteine(Hcy)and glutathione(GSH)play crucial roles in living systems,and their variations are closely associated with various diseases.Herein,we developed a near-infrared intramolecular charge transfer(ICT)based fluorescent probe Y-NBD,achieving detection of Cys/Hcy and H_(2)S with different fluorescent signals(green-red for Cys/Hcy,red for H_(2)S),large Stokes shifts(∼100/105nm or 191 nm)and high signal-background-ratio,but not responding to GSH.Y-NBD was successfully applied to image exogenous/endogenous Cys/Hcy and H_(2)S in various living cancer cells(HeLa,A549,and HepG2)and in zebrafish.It not only visualized the transformation pathway of several thiols in HepG2 cells but also verified that the intestine is the main site for the activation and metabolism of Y-NBD in zebrafish,as well as realized to evaluate the degree of drug-induced liver injury.This work provides a promising tool for imaging Cys/Hcy and H_(2)S in living systems and shows great potency in evaluating drug-induced liver injury and its treatment.
基金the National Natural Science Foundation of China(No.62173049)the Open Fund of the Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering(Yangtze University),YQZC202309.
文摘Conventional conductivity methods for measuring the void fraction in gas-liquid multiphase systems are typically affected by accuracy problems due to the presence of fluid flow and salinity.This study presents a novel approach for determining the void fraction based on a reciprocating dynamic conductivity probe used to measure the liquid film thickness under forced annular-flow conditions.The measurement system comprises a cyclone,a conductivity probe,a probe reciprocating device,and a data acquisition and processing system.This method ensures that the flow pattern is adjusted to a forced annular flow,thereby minimizing the influence of complex and variable gas-liquid flow patterns on the measurement results;Moreover,it determines the liquid film thickness solely according to circuit connectivity rather than specific conductivity values,thereby mitigating the impact of salinity.The reliability of the measurement system is demonstrated through laboratory experiments.The experimental results indicate that,in a range of gas phase superficial velocities 5–20 m/s and liquid phase superficial velocities 0.079–0.48 m/s,the maximum measurement deviation for the void fraction is 4.23%.
文摘A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phosphorescence(RTP)properties,was prepared by doping 2,6-naphthalic acid(P)into matrix1at a low con-centration.P@1emitted a green RTP that was visible to the naked eye and lasted for approximately 2 s.P@1exhib-ited selective phosphorescence enhancement response towards Pb^(2+),with a detection limit of 2.52μmol·L^(-1).Themain detection mechanism is the Pb—O coordination-induced phosphorescence enhancement in the system.Inter-estingly,P@1also functioned as a dual-channel probe for the rapid detection of Fe^(3+)ions through fluorescencequenching with a detection limit of 0.038μmol·L^(-1).The recognition mechanism may be attributed to the competi-tive energy absorption betweenP@1and Fe^(3+)ions.CCDC:2388502,1.
文摘To address the lack of systematic studies on heavy metal fluorescent probes in typical buffer solutions,this study developed a Fe^(3+)and Cu^(2+)fluorescent probe,DHU‑NP‑4,based on a naphthalimide fluorophore.Comparative analysis of the probe's performance in various buffer systems revealed that buffers with high organic content are unsuitable for evaluating such probes.Furthermore,the pH of the solvent system was found to significantly influence the probe's behavior.Under highly acidic conditions(pH≤2),DHU‑NP‑4 exhibited exceptional specificity for Fe^(3+),while in alkaline conditions,it demonstrated high specificity for Cu^(2+).Leveraging these properties,the probe enabled the quantitative detection of Fe^(3+)and Cu^(2+)in solution.
基金supported by the National Natural Science Foundation of China(Nos.82272067,81974386,M-0696,and 82273486)Natural Science Foundation of Hunan Province(Nos.2022JJ80052,2024JJ6596)the Innovation Fund for Postgraduate Students of Central South University(No.2023ZZTS0841)。
文摘Colorectal cancer(CRC)is one of the most prevalent malignant tumors worldwide,exhibiting high morbidity and mortality.Lack of efficient tools for early diagnosis and surgical resection guidance of CRC have been a serious threat to the long-term survival rate of the CRC patients.Recent studies have shown that relative higher viscosity was presented in tumor cells compared to that in normal cells,leading to viscosity as a potential biomarker for CRC.Herein,we reported the development of a series of novel viscosity-sensitive and mitochondria-specific fluorescent probes(HTB,HTI,and HTP)for CRC detection.Among them,HTB showed high sensitivity,minimal background interference,low cytotoxicity,and significant viscous response capability,making it an ideal tool for distinguishing colorectal tumor cells from normal cells.Importantly,we have successfully utilized HTB to visualize in a CRC-cells-derived xenograft(CDX)model,enriching its medical imaging capacity,which laid a foundation for further clinical translational application.
基金the National Natural Science Foundation of China(Nos.22325703,22377071,U23A6009)Research Project Supported by Shanxi Scholarship Council of China(No.2022-002)+1 种基金the Shanxi Province Science Foundation(No.202203021221009)Shanxi Province Science and Technology activities for overseas people selected funding project(No.2024001)。
文摘Rheumatoid arthritis(RA) is a chronic inflammatory disease with multi-system damage and autoimmune features.The main clinical manifestations of RA include joint pain,swelling,and stiffness,and RA may lead to joint deformity and dysfunction in severe cases.The pathologic development of RA involves complex interactions of multiple biomarkers,and detecting a single biomarker may produce falsepositive results due to other confounding factors.Therefore,fluorescent probes that can detect multiple biomarkers simultaneously are crucial for precise RA diagnosis.Peroxynitrite(ONOO^(-)) and viscosity are inflammation-related factors in cells.In this study,we developed a dual responsive near-infrared fluorescent probe,YLS,for ONOO^(-) and viscosity.The probe features dual-channel turn-on fluorescence responses at 625 and 760 nm upon the presence of ONOO^(-) and viscosity,respectively.Supported by YLS,we found that during RA pathology,lymphocyte infiltration not only increases the concentration of proteins in the joint fluid resulting in elevated viscosity;at the same time,the overproduction of ONOO^(-) exacerbates oxidative stress and inflammatory responses.This multiparameter assay is expected to improve the diagnostic accuracy of the early stages of RA,thus providing a scientific basis for early intervention and personalized treatment.
文摘In this study,a self-calibrating near-infrared fluorescence probe was designed and synthesized based on the dual-fluorophore strategy utilizing methylene blue and coumarin.The probe utilized methylene blue(emission spectrum range:640-740 nm)and coumarin fluorophore(emission spectrum range:440-600 nm)as signal output units,thereby achieving effective spectral separation and highly selective detection of HClO.Under physiological pH conditions,HClO triggers an oxidation-cleavage reaction,releasing methylene blue and coumarin,which emit distinct red and green fluorescence,respectively.This dual-emission feature enabled rapid HClO detection with two-channel detection limits of 25.13 nmol·L^(-1)(green channel)and 31.55 nmol·L^(-1)(red channel).Furthermore,in cell imaging experiments,this probe demonstrated excellent cell membrane permeability and low cytotoxicity,successfully enabling the monitoring of both endogenous and exogenous HClO in living cells.By incorporating a twochannel self-calibration system,the probe effectively mitigated signal variations caused by instrumental or environmental interference,substantially improving detection sensitivity and reliability.
文摘This article provides a short review on the importance of the detailed analysis of a Langmuir probe I-V trace in a multi-Maxwellian plasma,and discuss proper procedures analyzing Langmuir probe I-V traces in bi-Maxwellian and triple-Maxwellian Electron Energy Distribution Function(EEDF)plasmas.Discus⁃sion and demonstration of procedures include the treatment of the ion saturation current,electron saturation cur⁃rent,space-charge effects on the I-V trace,and most importantly how to properly isolate and fit for each electron group present in an I-V trace reflecting a mult-Maxwellian EEDF,as well as how having a multi-Maxwellian EEDF affects the procedures of treating the ion and electron saturation currents.Shortcomings of common improp⁃er procedures are discussed and demonstrated with simulated I-V traces to show how these procedures gives false measurements.
文摘The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic situation in the tumor.A fluorescence probe,AQD,with selective response toward hypoxia was designed for the detection of hypoxic tumor cells,which was obtained by the covalent connection of a large planar conjugated fluorophore with good fluorescence stability and a N,N-dimethylaniline moiety via the azo bond.The introduction of the azo bond in AQD caused significant fluorescence emission quenching,and the probe was reduced under hypoxic conditions to release the fluorophore via breaking the azo bond,resulting in the gradual recovery of fluorescence emission.Probe AQD exhibited a remarkable fluorescence response in hypoxic conditions,high selectivity,and good biocompatibility,which was successfully used for the imaging of hypoxic tumor cells and realized the detection of hypoxic A549 cells.
文摘Herein,a luminescent europium-based metal-organic framework(Eu-MOF,[Eu_(3)(L)(HL)(NO_(3))_(2)(DMF)_(2)]·4DMF·5H_(2)O,H_(4)L=5,5′-(pyrazine-2,6-diyl)diisophthalic acid,DMF=N,N-dimethylformamide)was developed for the dual-functional detection of environmental pollutants.This fluorescence-quenching-based sensor exhibited excep-tional sensitivity for both 2,4,6-trinitrophenol(TNP)and tetracycline(TC),achieving remarkably low detection lim-its of 1.96×10^(-6)and 1.71×10^(-7)mol·L^(-1),respectively.Notably,the system exhibited 99%fluorescence quenching ef-ficiency for TC,indicating ultra-efficient analyte recognition.The detection performance surpasses most reported lu-minescent MOF sensors,attributed to synergistic mechanisms of fluorescence resonance energy transfer(FRET)and photoinduced electron transfer(PET).CCDC:2446483.
基金financially supported by the Natural Science Foundation of Jiangsu Province(Grant No.BK20241181)the State Key Laboratory of AnalyticalChemistry for Life Science,School of Chemistry and Chemical Engineering,Nanjing University(Grant No.SKLACLS2419)。
文摘Using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran(TCF)as a near-infrared fluorescent chromophore,we designed and synthesized a TCF-based fluorescent probe TCF-NS by introducing 2,4-dinitrophenyl ether as the recognized site for H_(2)S.The probe TCF-NS displayed a rapid-response fluorescent against H_(2)S with high sensitivity and selection but had no significant fluorescence response to other biothiols.Furthermore,TCF-NS was applied to sense H_(2)S in living cells successfully with minimized cytotoxicity and a large Stokes shift.
基金financial support from the National Natural Science Foundation of China(Nos.82173652 and 81872728)the Natural Science Foundation of Jiangsu Province(No.BK20221522)+1 种基金Support from Jiangsu“333 High Level Talents Cultivation”Leading Talents(No.2022-3-16-203)the Qing Lan Project is also appreciated.
文摘Butyrylcholinesterase(BChE)is a pivotal enzyme that degrades the neurotransmitter acetylcholine,which is related to learning and memory,into choline and acetic acid.BChE activity is strongly associated with various diseases,including Alzheimer’s disease,multiple sclerosis,diabetes,and lipid metabolism disorders.It also possesses pharmacological properties for combating cocaine addiction and detoxifying organophosphate poisoning.Given the significant importance of BChE in the biological and medical fields,detecting its activity and understanding its expression in the body are crucial for advancing related research.Herein,a brief review of recently reported specific fluorescence or chemiluminescence probes for quantifying and real-time monitoring BChE is provided.By utilizing unique recognition groups,these probes achieve highly selective identification of BChE and effectively resist interference from other biological factors.Probes demonstrate excellent performance in measuring BChE activity,screening BChE inhibitors,and locating BChE in cells and mice.These also offer strong technical support for early diagnosis,precise intervention,and effective treatment of diseases with pathological changes in BChE.
基金supported by the National Natural Science Foundation of China(Nos.22225806,22078314,22278394,22378385)Dalian Institute of Chemical Physics(Nos.DICPI202142,DICPI202436).
文摘The overuse of surfactants has made them well-known environmental pollutants.So far,it is still a challenge to simultaneously distinguish cationic,anionic,zwitterionic,nonionic surfactants and surfactants with similar structures based on traditional analytical techniques.We developed a high-throughput method for distinguishing various surfactants based on the adaptive emission profile as fingerprints(AEPF).The fluorescence response of the sensor was based on the interaction between surfactants and 1,3-diacetylpyrene(o-DAP)probe.The interaction affected the reversible conversion of free molecules and two aggregates in the solution,thereby changing the relative abundance and the fluorescence intensity ratio of two aggregates emitting different fluorescence.The o-DAP sensor can distinguish four types of surfactants(16 surfactants),especially surfactants of the same type with similar structures.The o-DAP sensor sensitively determined the critical micelle concentration(CMC)of 16 surfactants based on the interaction between o-DAP and surfactants.Additionally,the o-DAP sensor can detect and distinguish artificial vesicles made from different surfactants.
基金National Natural Science Foundation of China(Nos.22277104,22325703,22074084)the Natural Science Foundation of Shanxi Province(No.202203021212184)+3 种基金Research Project supported by Shanxi Scholarship Council of China(No.2022-002)the Basic Research Program of Shanxi Province(Free Exploration)(No.202203021221009)2022 Lvliang City science and technology plan project(Nos.2022SHFZ51,2022GXYF15)Scientific Instrument Center of Shanxi University(No.201512)。
文摘Excited-state intramolecular proton-transfer(ESIPT)based fluorescence probes are particularly attractive due to their unique properties including environmental sensitivity,a large Stokes shift,and potential for ratiometric sensing.In general,ESIPT-based fluorophore incorporates an intramolecular hydrogen bonding interaction between a hydrogen bond donor(-OH and NH_(2)are common)and a hydrogen bond acceptor(C=N and C=O).More,protection-deprotection of hydroxyl group as hydrogen bond donor could induce an off-on switch of ESIPT-based emission.Therefore,protection-deprotection of hydroxyl group has been the widely used strategy to design fluorescent probes,where the potential key issue is selecting a protective group that can specifically leave in the presence of the target analyte.In this review,we mainly summarize the specific protecting groups(sites)and deprotection mechanisms for biologically important species(including reactive sulfur species(RSS),reactive oxygen species(ROS),enzymes,etc.),and analyze the advantages and disadvantages of different protection mechanisms from some aspects including probe stability,selectivity,response rate and assay system,etc.Based on the aforementioned,we further point out the current challenges and the potential future direction for developing ESIPT-based probes.
