Optical fiber technology has changed the world by enabling extraordinary growth in world-wide communications and sensing.The rapid development and wide deployment of optical fiber sensors are driven by their excellent...Optical fiber technology has changed the world by enabling extraordinary growth in world-wide communications and sensing.The rapid development and wide deployment of optical fiber sensors are driven by their excellent sensing performance with outstanding flexibility,functionality,and versatility.Notably,the research on specialty optical fibers is playing a critical role in enabling and proliferating the optical fiber sensing applications.This paper overviews recent developments in specialty optical fibers and their sensing applications.The specialty optical fibers are reviewed based on their innovations in special structures,special materials,and technologies to realize lab in/on a fiber.An overview of sensing applications in various fields is presented.The prospects and emerging research areas of specialty optical fibers are also discussed.展开更多
Lithium(Li)dendrite growth significantly deteriorates the performance and shortens the operation life of lithium metal batteries.Capturing the intricate dynamics of surface localized and rapid mass transport at the el...Lithium(Li)dendrite growth significantly deteriorates the performance and shortens the operation life of lithium metal batteries.Capturing the intricate dynamics of surface localized and rapid mass transport at the electrolyte–electrode interface of lithium metal is essential for the understanding of the dendrite growth process,and the evaluation of the solutions mitigating the dendrite growth issue.Here we demonstrate an approach based on an ultrasensitive tilted fiber Bragg grating(TFBG)sensor which is inserted close to the electrode surface in a working lithium metal battery,without disturbing its operation.Thanks to the superfine optical resonances of the TFBG,in situ and rapid monitoring of mass transport kinetics and lithium dendrite growth at the nanoscale interface of lithium anodes have been achieved.Reliable correlations between the performance of different natural/artificial solid electrolyte interphases(SEIs)and the time-resolved optical responses have been observed and quantified,enabling us to link the nanoscale ion and SEI behavior with the macroscopic battery performance.This new operando tool will provide additional capabilities for parametrization of the batteries’electrochemistry and help identify the optimal interphases of lithium metal batteries to enhance battery performance and its safety.展开更多
In this study,the future landslide population amount risk(LPAR)is assessed based on integrated machine learning models(MLMs)and scenario simulation techniques in Shuicheng County,China.Firstly,multiple MLMs were selec...In this study,the future landslide population amount risk(LPAR)is assessed based on integrated machine learning models(MLMs)and scenario simulation techniques in Shuicheng County,China.Firstly,multiple MLMs were selected and hyperparameters were optimized,and the generated 11 models were crossintegrated to select the best model to calculate landslide susceptibility;by calculating precipitation for different extreme precipitation recurrence periods and combining the susceptibility results to assess the landslide hazard.Using the town as the basic unit,the exposure and vulnerability of the future landslide population under different Shared Socioeconomic Pathways(SSPs)scenarios in each town were assessed,and then combined with the hazard to estimate the LPAR in 2050.The results showed that the integrated model with the optimized random forest model as the combination strategy had the best comprehensive performance in susceptibility assessment.The distribution of hazard classes is similar to susceptibility,and with an increase in precipitation,the low-hazard area and high-hazard decrease and shift to medium-hazard and very high-hazard classes.The high-risk areas for future landslide populations in Shuicheng County are mainly concentrated in the three southwestern towns with high vulnerability,whereas the northern towns of Baohua and Qinglin are at the lowest risk class.The LPAR increased with the intensity of extreme precipitation.The LPAR differs significantly among the SSPs scenarios,with the lowest in the“fossil-fueled development(SSP5)”scenario and the highest in the“regional rivalry(SSP3)”scenario.In summary,the landslide susceptibility model based on integrated machine learning proposed in this study has a high predictive capability.The results of future LPAR assessment can provide theoretical guidance for relevant departments to cope with future socioeconomic development challenges and make corresponding disaster prevention and mitigation plans to prevent landslide risks from a developmental perspective.展开更多
Elastic and stretchable functional fibers have drawn attentions from wide research field because of their unique advantages including high dynamic bending elasticity,stretchability and high mechanic strength.Lots of e...Elastic and stretchable functional fibers have drawn attentions from wide research field because of their unique advantages including high dynamic bending elasticity,stretchability and high mechanic strength.Lots of efforts have been made to find promising soft materials and improve the processing methods to fabricate the elastomer fibers with controllable fiber geometries and designable functionalities.Significant progress has been made and various interdisciplinary applications have been demonstrated based on their unique mechanical performance.A series of remarkable applications,involving biomedicine,optics,electronics,human machine interfaces etc.,have been successfully achieved.Here,we summarize main processing methods to fabricate soft and stretchable functional fibers using different types of elastic materials,which are either widely used or specifically developed.We also introduce some representative applications of multifunctional elastic fibers to reveal this promising research area.All these reported applications indicate that the fast innovated interdisciplinary area is of great potential and inspire more remarkable ideas in fiber sensing,soft electronics,functional fiber integration and other related research fields.展开更多
Liquid crystal photonic bandgap (LCPBG) fibers provide a versatile and robust platform for designing optical fiber devices, which are highly tunable and exhibit novel optical properties for manipulation of guided li...Liquid crystal photonic bandgap (LCPBG) fibers provide a versatile and robust platform for designing optical fiber devices, which are highly tunable and exhibit novel optical properties for manipulation of guided light. We review the research progress on design, fabrication and development of integrated LCPBG fiber devices.展开更多
Owing to the complexity and variability of global climate,the study of extreme events to ensure food security is particularly critical.The standardized precipitation requirement index(SPRI)and chilling injury index(I_...Owing to the complexity and variability of global climate,the study of extreme events to ensure food security is particularly critical.The standardized precipitation requirement index(SPRI)and chilling injury index(I_(Ci))were introduced using data from agrometeorological stations on the Songliao Plain between 1981 and 2020 to identify the spatial and temporal variability of drought,waterlogging,and low-temperature cold damage during various maize growth periods.Compound drought and low-temperature cold damage events(CDLEs)and compound waterlogging and low-temperature cold damage events(CWLEs)were then identified.To measure the intensity of compound events,the compound drought and low-temperature cold damage magnitude index(CDLMI),and compound waterlogging and low-temperature cold damage magnitude index(CWLMI)were constructed by fitting marginal distributions.Finally,the effects of extreme events of various intensities on maize output were examined.The findings demonstrate that:(1)There were significant differences in the temporal trends of the SPRI and ICiduring different maize growth periods.Drought predominated in the middle growth period(MP),waterlogging predominated in the early growth period(EP)and late growth period(LP),and both drought and waterlogging tended to increase in intensity and frequency.The frequency of low-temperature cold damage showed a decreasing trend in all periods.(2)The CDLMI and CWLMI can effectively determine the intensity of CDLEs and CWLEs in the study area;these CDLEs and CWLEs had higher intensity and frequency in the late growth period.(3)Compared to single events,maize relative meteorological yield had a more significant negative correlation with the CDLMI and CWLMI.展开更多
The apparent increase in hormone-induced cancers and disorders of the reproductive tract has led to a growing demand for new technologies capable of detecting endocrine disruptors.However,a long-lasting challenge unad...The apparent increase in hormone-induced cancers and disorders of the reproductive tract has led to a growing demand for new technologies capable of detecting endocrine disruptors.However,a long-lasting challenge unaddressed is how to achieve ultrahigh sensitive,continuous,and in situ measurement with a portable device for infield and remote environmental monitoring.Here we demonstrate a simple-to-implement plasmonic optical fiber biosensing platform to achieve an improved light–matter interaction and advanced surface chemistry for ultrasensitive detection of endocrine disruptors.Our platform is based on a gold-coated highly tilted fiber Bragg grating that excites high-density narrow cladding mode spectral combs that overlap with the broad absorption of the surface plasmon for high accuracy interrogation,hence enabling the ultrasensitive monitoring of refractive index changes at the fiber surface.Through the use of estrogen receptors as the model,we design an estradiol–streptavidin conjugate with the assistance of molecular dynamics,converting the specific recognition of environmental estrogens(EEs)by estrogen receptor into surface-based affinity bioassay for protein.The ultrasensitive platform with conjugate-induced amplification biosensing approach enables the subsequent detection for EEs down to 1.5×10−3 ng ml−1 estradiol equivalent concentration level,which is one order lower than the defined maximal E2 level in drinking water set by the Japanese government.The capability to detect EEs down to nanogram per liter level is the lowest limit of detection for any estrogen receptor-based detection reported thus far.Its compact size,flexible shape,and remote operation capability open the way for detecting other endocrine disruptors with ultrahigh sensitivity and in various hard-toreach spaces,thereby having the potential to revolutionize environment and health monitoring.展开更多
As the fundamental building block of optical fiber communication technology,thermally drawn optical fibers have fueled the development and prosperity of modern information society.However,the conventional step-index c...As the fundamental building block of optical fiber communication technology,thermally drawn optical fibers have fueled the development and prosperity of modern information society.However,the conventional step-index configured silica optical fibers have scarcely altered since their invention.In recent years,thermally drawn multifunctional fibers have emerged as a new yet promising route to enable unprecedented development in information technology.By adopting the well-developed preform-to-fiber manufacturing technique,a broad range of functional materials can be seamlessly integrated into a single fiber on a kilometer length scale to deliver sophisticated functions.Functions such as photodetection,imaging,acoustoelectric detection,chemical sensing,tactile sensing,biological probing,energy harvesting and storage,data storage,program operation,and information processing on fiber devices.In addition to the original light-guiding function,these flexible fibers can be woven into fab-rics to achieve large-scale personal health monitoring and interpersonal com-munication.Thermally drawn multifunctional fibers have opened up a new stage for the next generation of information technology.This review article summarizes an overview of the basic concepts,fabrication processes,and developments of multifunctional fibers.It also highlights the significant pro-gress and future development in information applications.展开更多
In situ and continuous monitoring of thermal effects is essential for understanding photo-induced catalytic processes at catalyst's surfaces.However,existing techniques are largely unable to capture the rapidly ch...In situ and continuous monitoring of thermal effects is essential for understanding photo-induced catalytic processes at catalyst's surfaces.However,existing techniques are largely unable to capture the rapidly changing temperatures occurring in sub-μm layers at liquid-solid interfaces exposed to light.To address this,a sensing system based on a gold-coated conventional single-mode optical fiber with a tilted fiber Bragg grating inscribed in the fiber core is proposed and demonstrated.The spectral transmission from these devices is made up of a dense comb of narrowband resonances that can differentiate between localized temperatures rapid changes at the catalyst's surface and those of the environment.By using the gold coating of the fiber as an electrode in an electrochemical reactor and exposing it to light,thermal effects in photo-induced catalysis at the interface can be decoded with a temperature resolution of 0.1℃and a temporal resolution of 0.1 sec,without perturbing the catalytic operation that is measured simultaneously.As a demonstration,stable and reproducible correlations between the light-to-heat conversion and catalytic activities over time were measured for two different catalysis processes(linear and nonlinear).These kinds of sensing applications are ideally suited to the fundamental qualities of optical fiber sensors,such as their compact size,flexible shape,and remote measurement capability,thereby opening the way for various thermal monitoring in hard-to-reach spaces and rapid catalytic reaction processes.展开更多
As real-world graphs are often evolving over time, interest in analyzing the temporal behavior of graphs has grown. Herein, we propose Auxo, a novel temporal graph management system to support temporal graph analysis....As real-world graphs are often evolving over time, interest in analyzing the temporal behavior of graphs has grown. Herein, we propose Auxo, a novel temporal graph management system to support temporal graph analysis. It supports both efficient global and local queries with low space overhead. Auxo organizes temporal graph data in spatio-temporal chunks. A chunk spans a particular time interval and covers a set of vertices in a graph.We propose chunk layout and chunk splitting designs to achieve the desired efficiency and the abovementioned goals. First, by carefully choosing the time split policy, Auxo achieves linear complexity in both space usage and query time. Second, graph splitting further improves the worst-case query time, and reduces the performance variance introduced by splitting operations. Third, Auxo optimizes the data layout inside chunks, thereby significantly improving the performance of traverse-based graph queries. Experimental evaluation showed that Auxo achieved 2:9 to 12:1 improvement for global queries, and 1:7 to 2:7 improvement for local queries, as compared with state-of-the-art open-source solutions.展开更多
基金We are grateful for financial supports from Special Funds for the Major Fields of Colleges and Universities by the Department of Education of Guangdong Province(2021ZDZX1023)Natural Science Foundation of Guangdong Province(No.2022A1515011434)+4 种基金Stable Support Program for Higher Education Institutions from Shenzhen Science,Technology&Innovation Commission(20200925162216001)Guangdong Basic and Applied Basic Research Foundation(2021B1515120013)Open Fund of State Key Laboratory of Information Photonics and Optical Communications(Beijing University of Posts and Telecommunications,No.IPOC2020A002)The Open Projects Foundation of State Key Laboratory of Optical Fiber and Cable Manufacture Technology(No.SKLD2105)General Program of Shenzhen Science,Technology&Innovation Commission(JCYJ20220530113811026).
文摘Optical fiber technology has changed the world by enabling extraordinary growth in world-wide communications and sensing.The rapid development and wide deployment of optical fiber sensors are driven by their excellent sensing performance with outstanding flexibility,functionality,and versatility.Notably,the research on specialty optical fibers is playing a critical role in enabling and proliferating the optical fiber sensing applications.This paper overviews recent developments in specialty optical fibers and their sensing applications.The specialty optical fibers are reviewed based on their innovations in special structures,special materials,and technologies to realize lab in/on a fiber.An overview of sensing applications in various fields is presented.The prospects and emerging research areas of specialty optical fibers are also discussed.
基金supported by the National Natural Science Foundation of China(Nos.62035006 and U2033204)the Guangdong Outstanding Scientific Innovation Foundation(No.2019TX05X383)+2 种基金the Program of Marine Economy Development Special Fund under Department of Natural Resources of Guangdong Province(No.GDNRC[2023]23)J.H.is indebted to National Natural Science Foundation of China(No.52207230)Guangzhou Municipal Science and Technology Project(Nos.2023A03J0003 and 2023A03J0103).
文摘Lithium(Li)dendrite growth significantly deteriorates the performance and shortens the operation life of lithium metal batteries.Capturing the intricate dynamics of surface localized and rapid mass transport at the electrolyte–electrode interface of lithium metal is essential for the understanding of the dendrite growth process,and the evaluation of the solutions mitigating the dendrite growth issue.Here we demonstrate an approach based on an ultrasensitive tilted fiber Bragg grating(TFBG)sensor which is inserted close to the electrode surface in a working lithium metal battery,without disturbing its operation.Thanks to the superfine optical resonances of the TFBG,in situ and rapid monitoring of mass transport kinetics and lithium dendrite growth at the nanoscale interface of lithium anodes have been achieved.Reliable correlations between the performance of different natural/artificial solid electrolyte interphases(SEIs)and the time-resolved optical responses have been observed and quantified,enabling us to link the nanoscale ion and SEI behavior with the macroscopic battery performance.This new operando tool will provide additional capabilities for parametrization of the batteries’electrochemistry and help identify the optimal interphases of lithium metal batteries to enhance battery performance and its safety.
基金supported by“The National Key Research and Development Program of China(2018YFC1508804)The Key Scientific and Technology Program of Jilin Province(20170204035SF)+2 种基金The Key Scientific and Technology Research and Development Program of Jilin Province(20200403074SF)The Key Scientific and Technology Research and Development Program of Jilin Province(20180201035SF)National Natural Science Fund for Young Scholars of China(41907238)”.
文摘In this study,the future landslide population amount risk(LPAR)is assessed based on integrated machine learning models(MLMs)and scenario simulation techniques in Shuicheng County,China.Firstly,multiple MLMs were selected and hyperparameters were optimized,and the generated 11 models were crossintegrated to select the best model to calculate landslide susceptibility;by calculating precipitation for different extreme precipitation recurrence periods and combining the susceptibility results to assess the landslide hazard.Using the town as the basic unit,the exposure and vulnerability of the future landslide population under different Shared Socioeconomic Pathways(SSPs)scenarios in each town were assessed,and then combined with the hazard to estimate the LPAR in 2050.The results showed that the integrated model with the optimized random forest model as the combination strategy had the best comprehensive performance in susceptibility assessment.The distribution of hazard classes is similar to susceptibility,and with an increase in precipitation,the low-hazard area and high-hazard decrease and shift to medium-hazard and very high-hazard classes.The high-risk areas for future landslide populations in Shuicheng County are mainly concentrated in the three southwestern towns with high vulnerability,whereas the northern towns of Baohua and Qinglin are at the lowest risk class.The LPAR increased with the intensity of extreme precipitation.The LPAR differs significantly among the SSPs scenarios,with the lowest in the“fossil-fueled development(SSP5)”scenario and the highest in the“regional rivalry(SSP3)”scenario.In summary,the landslide susceptibility model based on integrated machine learning proposed in this study has a high predictive capability.The results of future LPAR assessment can provide theoretical guidance for relevant departments to cope with future socioeconomic development challenges and make corresponding disaster prevention and mitigation plans to prevent landslide risks from a developmental perspective.
基金supported by the Singapore Ministry of Education Academic Research Fund Tier 2(MOE2019-T2-2-127 and T2EP50120-0005)A*STAR under AME IRG(A2083c0062)+2 种基金the Singapore Ministry of Education Academic Research Fund Tier 1(RG90/19 and RG73/19)the Singapore National Research Foundation Competitive Research Program(NRF-CRP18-2017-02)supported by Nanyang Technological University.
文摘Elastic and stretchable functional fibers have drawn attentions from wide research field because of their unique advantages including high dynamic bending elasticity,stretchability and high mechanic strength.Lots of efforts have been made to find promising soft materials and improve the processing methods to fabricate the elastomer fibers with controllable fiber geometries and designable functionalities.Significant progress has been made and various interdisciplinary applications have been demonstrated based on their unique mechanical performance.A series of remarkable applications,involving biomedicine,optics,electronics,human machine interfaces etc.,have been successfully achieved.Here,we summarize main processing methods to fabricate soft and stretchable functional fibers using different types of elastic materials,which are either widely used or specifically developed.We also introduce some representative applications of multifunctional elastic fibers to reveal this promising research area.All these reported applications indicate that the fast innovated interdisciplinary area is of great potential and inspire more remarkable ideas in fiber sensing,soft electronics,functional fiber integration and other related research fields.
文摘Liquid crystal photonic bandgap (LCPBG) fibers provide a versatile and robust platform for designing optical fiber devices, which are highly tunable and exhibit novel optical properties for manipulation of guided light. We review the research progress on design, fabrication and development of integrated LCPBG fiber devices.
基金supported by the National K&D Program of China(2022YFD2300201)the National Natural Science Foundation of China(U21A2040)+4 种基金the Major Science and Technology Program of Jilin Province(YDZJ202303CGZH023)the National Natural Science Foundation of China(42077443)the Science and Technology Development Planning of Jilin Province(20210203153SF)the Key Scientific and Technology Research and Development Program of Jilin Province(20200403065 SF)the Construction Project of the Science and Technology Innovation Center(20210502008ZP).
文摘Owing to the complexity and variability of global climate,the study of extreme events to ensure food security is particularly critical.The standardized precipitation requirement index(SPRI)and chilling injury index(I_(Ci))were introduced using data from agrometeorological stations on the Songliao Plain between 1981 and 2020 to identify the spatial and temporal variability of drought,waterlogging,and low-temperature cold damage during various maize growth periods.Compound drought and low-temperature cold damage events(CDLEs)and compound waterlogging and low-temperature cold damage events(CWLEs)were then identified.To measure the intensity of compound events,the compound drought and low-temperature cold damage magnitude index(CDLMI),and compound waterlogging and low-temperature cold damage magnitude index(CWLMI)were constructed by fitting marginal distributions.Finally,the effects of extreme events of various intensities on maize output were examined.The findings demonstrate that:(1)There were significant differences in the temporal trends of the SPRI and ICiduring different maize growth periods.Drought predominated in the middle growth period(MP),waterlogging predominated in the early growth period(EP)and late growth period(LP),and both drought and waterlogging tended to increase in intensity and frequency.The frequency of low-temperature cold damage showed a decreasing trend in all periods.(2)The CDLMI and CWLMI can effectively determine the intensity of CDLEs and CWLEs in the study area;these CDLEs and CWLEs had higher intensity and frequency in the late growth period.(3)Compared to single events,maize relative meteorological yield had a more significant negative correlation with the CDLMI and CWLMI.
基金This research was supported by National Key Research and Development Project(2019YFD1100505)the Key Program of National Natural Science Foundation of China(62035006)the National Natural Science Foundation of China(21976100,61975068,62005101,62011530459)。
文摘The apparent increase in hormone-induced cancers and disorders of the reproductive tract has led to a growing demand for new technologies capable of detecting endocrine disruptors.However,a long-lasting challenge unaddressed is how to achieve ultrahigh sensitive,continuous,and in situ measurement with a portable device for infield and remote environmental monitoring.Here we demonstrate a simple-to-implement plasmonic optical fiber biosensing platform to achieve an improved light–matter interaction and advanced surface chemistry for ultrasensitive detection of endocrine disruptors.Our platform is based on a gold-coated highly tilted fiber Bragg grating that excites high-density narrow cladding mode spectral combs that overlap with the broad absorption of the surface plasmon for high accuracy interrogation,hence enabling the ultrasensitive monitoring of refractive index changes at the fiber surface.Through the use of estrogen receptors as the model,we design an estradiol–streptavidin conjugate with the assistance of molecular dynamics,converting the specific recognition of environmental estrogens(EEs)by estrogen receptor into surface-based affinity bioassay for protein.The ultrasensitive platform with conjugate-induced amplification biosensing approach enables the subsequent detection for EEs down to 1.5×10−3 ng ml−1 estradiol equivalent concentration level,which is one order lower than the defined maximal E2 level in drinking water set by the Japanese government.The capability to detect EEs down to nanogram per liter level is the lowest limit of detection for any estrogen receptor-based detection reported thus far.Its compact size,flexible shape,and remote operation capability open the way for detecting other endocrine disruptors with ultrahigh sensitivity and in various hard-toreach spaces,thereby having the potential to revolutionize environment and health monitoring.
基金A*STAR under AME IRG,Grant/Award Number:A2083c0062Funding of Innovation Academy for Light-duty Gas Turbine,Chinese Academy of Sciences,Grant/Award Number:CXYJJ21-ZD-02+6 种基金National Natural Science Foundation of China,Grant/Award Numbers:51976215,52172249,62005101Schaeffler Hub for Advanced Research at NTU,under the ASTAR IAF-ICP Programme,Grant/Award Number:ICP1900093Scientific Instrument Developing Project of the Chinese Academy of Sciences,Grant/Award Number:YJKYYQ20200017Singapore Ministry of Education Academic Research Fund Tier 1,Grant/Award Numbers:MOE2019-T1-001-103(RG 73/19),MOE2019-T1-001-111(RG 90/19)Singapore Ministry of Education Academic Research Fund Tier 2,Grant/Award Numbers:MOE-T2EP50120-0002,MOE2019-T2-2-127Singapore National Research Foundation Competitive Research Program,Grant/Award Number:NRF-CRP18-2017-02Nanyang Technological University。
文摘As the fundamental building block of optical fiber communication technology,thermally drawn optical fibers have fueled the development and prosperity of modern information society.However,the conventional step-index configured silica optical fibers have scarcely altered since their invention.In recent years,thermally drawn multifunctional fibers have emerged as a new yet promising route to enable unprecedented development in information technology.By adopting the well-developed preform-to-fiber manufacturing technique,a broad range of functional materials can be seamlessly integrated into a single fiber on a kilometer length scale to deliver sophisticated functions.Functions such as photodetection,imaging,acoustoelectric detection,chemical sensing,tactile sensing,biological probing,energy harvesting and storage,data storage,program operation,and information processing on fiber devices.In addition to the original light-guiding function,these flexible fibers can be woven into fab-rics to achieve large-scale personal health monitoring and interpersonal com-munication.Thermally drawn multifunctional fibers have opened up a new stage for the next generation of information technology.This review article summarizes an overview of the basic concepts,fabrication processes,and developments of multifunctional fibers.It also highlights the significant pro-gress and future development in information applications.
基金support of Key Program of National Natural Science Foundation of China(No.62035006),National Natural Science Foundation of China(No.61975068.No.62011530459)and Guangdong Outstanding Scientific Innovation Foundation(No.2019TX05X383)and Program of Marine Economy Development Special Fund(Six Marine Industies)under Department of Natural Resources of Guangdong Province(No.GDNRC[2021133).MZ acknowledges the support of Guangdong Basic Applied Basic Research Foundation(No.202081515020038)and Pearl River Talent Recutment Program of Guangdong Province(No.2019QN01L148).JA acknowledges the support of NSERC(RGPIN-2019-06255).
文摘In situ and continuous monitoring of thermal effects is essential for understanding photo-induced catalytic processes at catalyst's surfaces.However,existing techniques are largely unable to capture the rapidly changing temperatures occurring in sub-μm layers at liquid-solid interfaces exposed to light.To address this,a sensing system based on a gold-coated conventional single-mode optical fiber with a tilted fiber Bragg grating inscribed in the fiber core is proposed and demonstrated.The spectral transmission from these devices is made up of a dense comb of narrowband resonances that can differentiate between localized temperatures rapid changes at the catalyst's surface and those of the environment.By using the gold coating of the fiber as an electrode in an electrochemical reactor and exposing it to light,thermal effects in photo-induced catalysis at the interface can be decoded with a temperature resolution of 0.1℃and a temporal resolution of 0.1 sec,without perturbing the catalytic operation that is measured simultaneously.As a demonstration,stable and reproducible correlations between the light-to-heat conversion and catalytic activities over time were measured for two different catalysis processes(linear and nonlinear).These kinds of sensing applications are ideally suited to the fundamental qualities of optical fiber sensors,such as their compact size,flexible shape,and remote measurement capability,thereby opening the way for various thermal monitoring in hard-to-reach spaces and rapid catalytic reaction processes.
基金supported by the National High-Tech Development Plan of China (No. 2015AA015306)the National Natural Science Foundation of China (No. 61772302)
文摘As real-world graphs are often evolving over time, interest in analyzing the temporal behavior of graphs has grown. Herein, we propose Auxo, a novel temporal graph management system to support temporal graph analysis. It supports both efficient global and local queries with low space overhead. Auxo organizes temporal graph data in spatio-temporal chunks. A chunk spans a particular time interval and covers a set of vertices in a graph.We propose chunk layout and chunk splitting designs to achieve the desired efficiency and the abovementioned goals. First, by carefully choosing the time split policy, Auxo achieves linear complexity in both space usage and query time. Second, graph splitting further improves the worst-case query time, and reduces the performance variance introduced by splitting operations. Third, Auxo optimizes the data layout inside chunks, thereby significantly improving the performance of traverse-based graph queries. Experimental evaluation showed that Auxo achieved 2:9 to 12:1 improvement for global queries, and 1:7 to 2:7 improvement for local queries, as compared with state-of-the-art open-source solutions.