A new analytical method is proposed for the determination of heroin based on a sequential perturbation caused by trace amounts of heroin in the Cu(Ⅱ)-catalyzed oscillating reaction between hydrogen peroxide and sodiu...A new analytical method is proposed for the determination of heroin based on a sequential perturbation caused by trace amounts of heroin in the Cu(Ⅱ)-catalyzed oscillating reaction between hydrogen peroxide and sodium thiocyanate in an alkaline medium with the aid of a continuous-flow stirred tank reactor(CSTR). The method relies on the linear relationship between the change in oscillation period of the system and the concentration of heroin, with a detecting limit of 4.0×10^(-7) mol/L. The calibration curve fits a linear equation very well when the concentration of heroin is in the range of 2.0×10^(-6)_1.2×10^(-5) mol/L(r=0.9971). This method features good precision(RSD=0.98%). The influences of temperature, injection point, flow rate and reaction variables on the oscillation period were investigated in detail and a possible mechanism of the performance of heroin in the Cu(Ⅱ)-catalyzed oscillating reaction system is also discussed. The proposed method opens a new avenue for the determination of heroin.展开更多
The aim of the present investigation was to develop a biosensor for the detection of amino acids, Leucine, Isoleucine and Valine based on a quartz crystal nanobalance. leucine (Leu), isoleucine (Ile), and valine (Val)...The aim of the present investigation was to develop a biosensor for the detection of amino acids, Leucine, Isoleucine and Valine based on a quartz crystal nanobalance. leucine (Leu), isoleucine (Ile), and valine (Val) were selectively determined by quartz crystal nanobalance (QCN) sensor in conjunction with net analyte signal (NAS)-based method called HLA/GO. An orthogonal design was applied for the formation of calibration and prediction sets including Leu, Ile and Val compounds. The selection of the optimal time range involved the calculation of the net analyte sig-nal regression plot in any considered time window for each test sample. The searching of a region with maximum linearity of NAS regression plot (minimum error indicator) and minimum of PRESS value was carried out by applying a moving window strategy. On the base of obtained results, the differences on the adsorption profiles in the time range between 1 and 300 s were used to determine mixtures of compounds by HLA/GO method. The results showed that the method was successfully applied for the determina-tion of Leu, Ile and Val.展开更多
Surface-enhanced Raman scattering(SERS)platform,which enables trace analyte detection,has important application prospects.By structuring/modifying the surface of the SERSsubstrate,analyte in highly diluted solutions c...Surface-enhanced Raman scattering(SERS)platform,which enables trace analyte detection,has important application prospects.By structuring/modifying the surface of the SERSsubstrate,analyte in highly diluted solutions can be concentrated into localized active areas for highly sensitive detection.However,subject to the difficulty of the fabrication process,itremains challenging to balance hot-spot construction and the concentration capacity of analyte simultaneously.Therefore,preparing SERS substrates with densely ordered hot spots andefficient concentration capacity is of great significance for highly sensitive detection.Herein,we propose an Ag and fluoroalkyl-modified hierarchical armour substrate(Ag/F-HA),which has a double-layer stacking design to combine analyte concentration with hotspot construction.The microarmour structure is fabricated by femtosecond-laser processing to serve as asuperhydrophobic and low-adhesive surface to concentrate analyte,while the anodic aluminium oxide(AAO)template creates a nanopillar array serving as dense and ordered hot spots.Under the synergistic action of hot spots and analyte concentration,Ag/F-HA achieves a detectionlimit down to 10^(-7)M doxorubicin(DOX)molecules with a RSD of 7.69%.Additionally,Ag/F-HA exhibits excellent robustness to resist external disturbances such as liquid splash or abrasion.Based on our strategy,SERS substrates with directional analyte concentrations are further explored by patterning microcone arrays with defects.This work opens a way to the realistic implementation of SERS in diverse scenarios.展开更多
DETECHIP is a detection system made of various sensors that has been shown to detect and discriminate between small molecules of interest, including various illicit and over-the-counter drugs. Previously, detection wa...DETECHIP is a detection system made of various sensors that has been shown to detect and discriminate between small molecules of interest, including various illicit and over-the-counter drugs. Previously, detection was normalized to a single concentration of analyte. Now this detection assay can detect concentration differences in analytes via red, green, and blue color value changes and shifts in the UV-Vis spectra of the assay. To determine the concentrations differences, the exposed assays were scanned on a flatbed scanner and the images were analyzed for individual RGB values with a custom macro in ImageJ, an image analysis program. Increasing concentrations of the analyte resulted in greater differences in color values between control and analyte wells. These differences showed a linear relationship to concentration change, some with correlation coefficients greater than 98%. This work expands the capability of DETECHIP to give information about the concentration of analyte when the analyte identity is known.展开更多
A novel method for simultaneous determination of kolliphor HS15 and miglyol 812 in microemulsion formulation was developed using ultra-high performance liquid chromatography coupled with a nano quantitation analytical...A novel method for simultaneous determination of kolliphor HS15 and miglyol 812 in microemulsion formulation was developed using ultra-high performance liquid chromatography coupled with a nano quantitation analytical detector （UHPLC-NQAD）. All components in kolliphor HS15 and miglyo1812 were well separated on an Acquity BEH C18 column. Mobile phase A was 0.1% trifluoroacetic acid （TFA） in water and mobile phase B was acetonitrile. A gradient elution sequence was programed initially with 60% organic solvent, slowly increased to 100% within 8 min. The flow rate was 0.7 mL/min. Good linearity （r 〉 0.95） was obtained in the range of 27.6-1381.1 μg/mL for polyoxyl 15 hydroxystearate in kolliphor HS15, 0.8-202.0 μg/mL for caprylic acid triglyceride and 2.7-221.9μg/mL for capric acid triglyceride in miglyol 812. The relative standard deviations （RSD） ranged from 0.6% to 1.7% for intra-day precision and from 0.4% to 2.7% for inter-day precision. The overall recoveries （accuracy） were 99.7%-101.4% for polyoxyl 15 hydroxystearate in kolliphor HS15, 96.7%-99.6% for caprylic acid triglyceride, and 94.1%- 103.3% for capric acid triglyceride in miglyol 812. Quantification limits （QL） were determined as 27.6 μg/ mL for polyoxy115 hydroxystearate in kolliphor HS15, 0.8 μg/mL for caprylic acid triglyceride, and 2.7 μg/ mL for capric acid triglyceride in miglyol 812. No interferences were observed in the retention time ranges of kolliphor HSI5 and miglyol 812. The method was validated in terms of specificity, linearity, precision, accuracy, QL, and robustness. The proposed method has been applied to microemulsion for- mulation analyses with good recoveries （82.2%-103.4%）.展开更多
Sulfur is a soft Lewis base and thiocarbonyl has moderate electrophilicity.Our probe’s properties are adjusted in such a way that it could simultaneously detect a Lewis acid(Hg^(2+))and a strong nucleophile(NH_(2)-NH...Sulfur is a soft Lewis base and thiocarbonyl has moderate electrophilicity.Our probe’s properties are adjusted in such a way that it could simultaneously detect a Lewis acid(Hg^(2+))and a strong nucleophile(NH_(2)-NH_(2)).Considering the above fact,a thioureido-functionalized robust MOF material was prepared,which was utilized for the selective fluorometric detection of environmentally significant toxic pollutants(Hg^(2+)and NH_(2)-NH_(2))in an aqueous medium.展开更多
Voltammetric analytical techniques combine exceptional sensitivity,low cost,portability and capability for simultaneous determination of multiple analytes.The sensitivity of voltammetric analysis is largely determined...Voltammetric analytical techniques combine exceptional sensitivity,low cost,portability and capability for simultaneous determination of multiple analytes.The sensitivity of voltammetric analysis is largely determined by the efficiency of the working electrode.Electrodes modified with metal organic frameworks(MOFs)seem particularly promising for use in the analysis of a series of important inorganic and organic analytes.Nevertheless,research on chemically modified electrodes with MOFs is still in its infancy.In this critical review,we present the current status of research related to MOF-modified electrodes highlighting the respective MOF-modified electrodes which are based on MOFs that show exceptional chemical stability or/and sorption capability towards the targeted analytes.We also provide perspectives for future research aiming at motivating additional scientists to be involved in this exciting field of MOF-based electroanalytical sensors.展开更多
Monitoring multiplexed biochemical markers is beneficial for the comprehensive evaluation of diabetes-associated complications.Techniques for multiplexed analyses in interstitial fluids have often been restricted by t...Monitoring multiplexed biochemical markers is beneficial for the comprehensive evaluation of diabetes-associated complications.Techniques for multiplexed analyses in interstitial fluids have often been restricted by the difficulties of electrode materials in accurately detecting chemicals in complex subcutaneous spaces.In particular,the signal stability of enzyme-based sensing electrodes often inevitably decreases due to enzyme degradation or interference in vivo.In this study,we developed a self-calibrating multiplexed microneedle(MN)electrode array(SC-MMNEA)capable of continuous,real-time monitoring of multiple types of bioanalytes(glucose,cholesterol,uric acid,lactate,reactive oxygen species[ROSs],Na+,K+,Ca2+,and pH)in the subcutaneous space.Each type of analyte was detected by a discrete MN electrode assembled in an integrated array with single-MN resolution.Moreover,this device utilized an MN-delivery-mediated self-calibration technique to address the inherent problem of decreased accuracy of implantable electrodes caused by long-term tissue variation and enzyme degradation,and this technique might increase the reliability of the MN sensors.Our results indicated that SC-MMNEA could provide real-time monitoring of multiplexed analyte concentrations in a rat model with good accuracy,especially after self-calibration.SC-MMNEA has the advantages of in situ and minimally invasive monitoring of physiological states and the potential to promote wearable devices for long-term monitoring of chemical species in vivo.展开更多
A wearable multiplex sweat sensing patch with low sweat volume requirement and uniform distribution is highly desirable for noninvasive,real-time monitoring of various health-related biomarkers.The patch features a mu...A wearable multiplex sweat sensing patch with low sweat volume requirement and uniform distribution is highly desirable for noninvasive,real-time monitoring of various health-related biomarkers.The patch features a multi-channel microfluidic system inspired by cnidarians.It comprises of symmetric super-hydrophilic/super-hydrophobic patterned wedge channels allowing for simultaneous analysis of multiple analytes present in sweat.It ensures a uniform sweat transport and equal volume distribution across multiple sensing zones for a more accurate and reliable electrochemical sensing.As a proof of concept,a four-channel system housing sensors for glucose,lactate,urea,and pH was tested.The innovation lies in a unique surface design and electrode configuration utilizing PDMS-TiO_(2)nanocomposite coating,integrating channels with electrodes,presenting a novel approach for accurate low-volume sweat analysis requiring a minimum of 4µL.An on-body test was conducted to demonstrate the practical application of the patch.In addition,the physics of droplet splitting was explained through simulations.展开更多
Rapid and sensitive detection of various analytes is in high demand.Apart from its application in genome editing,CRISPR-Cas also shows promises in nucleic acid detection applications.To further exploit the potential o...Rapid and sensitive detection of various analytes is in high demand.Apart from its application in genome editing,CRISPR-Cas also shows promises in nucleic acid detection applications.To further exploit the potential of CRISPR-Cas for detection of diverse analytes,we present a versatile biosensing platform that couples the excellent affinity of aptamers for broad-range analytes with the collateral single-strand DNA cleavage activity of CRISPR-Cas12 a.We demonstrated that the biosensors developed by this platform can be used to detect protein and small molecule in human serum with a complicated background,i.e.,the tumor marker alpha fetoprotein and cocaine with the detection limits of 0.07 fmol/L and 0.34 lmol/L,respectively,highlighting the advantages of simplicity,sensitivity,short detection time,and low cost compared with the state-of-the-art biosensing approaches.Altogether,this biosensing platform with plug-and-play design show great potential in the detection of diverse analytes.展开更多
This paper deals with carbon emissions reduction through building material selection in housing construction using Analytical Hierarchy Process(AHP)method.Drawing on the concept of Sustainable Development in the Envir...This paper deals with carbon emissions reduction through building material selection in housing construction using Analytical Hierarchy Process(AHP)method.Drawing on the concept of Sustainable Development in the Environment(SDE),inadequate selection of building materials makes a significant contribution to carbon emissions.The achievability of the goal of SDE is in rethinking Locally Sourced and Recycled Building Materials(LSRBMs)selection decision making,in acknowledging cultural issues,towards the wider industrial use of Recycled Concrete Crushed Block Wall(RCCBW)which is about 66%,in carbon emissions,as good as Air-crete Hollow Block Wall(AHBW).With results derived from questionnaire survey with recruited civil engineers and architects,key sustainability principle indicators influencing the selection of building materials are identified,analysed,grouped and ranked using AHP,a concept of measurement through pairwise comparisons of tangible and intangible factors to derive priority scales in relative terms.This explained 17.27%cut back in carbon emissions for selecting Compressed Stabilized Rammed-Earth Block Wall(CSREBW)instead of AHBW.The lack of informed knowledge in the wider use of RCCBW and CSREDW and in the Ghanaian context towards future reduction in carbon emissions in the housing sector of the construction industry of Ghana.Subsequently,the study yielded the following theoretical,practical and policy implications:A new interpretation of existing building materials;Understanding the impact of building materials’attributes;In effect,might be beneficial to universities and organizations to come up with training policies that aim to take advantage of the new technology respectively.展开更多
Quick and accurate determination of the optimal synchrophase angle is crucial for synchrophasing control of multi-propeller aircraft with low noise.This paper proposes a novel noise prediction and optimization strateg...Quick and accurate determination of the optimal synchrophase angle is crucial for synchrophasing control of multi-propeller aircraft with low noise.This paper proposes a novel noise prediction and optimization strategy,developing a continuous and accurate noise prediction model and obtaining its minimum by solving the Hessian matrix and Fourier-Frobenius matrix.Firstly,a novel propeller noise prediction method uses acoustic simulation pressure signals and improved propeller signatures theory to accurately estimate noise for all synchrophase angles and receiving points.Secondly,a novel optimization approach is proposed to solve the analytical solution of the minimum propeller noise:(A)A noise objective function is established,and use its first derivatives’zeros and Hessian matrix to determine the function minimum.(B)A novel Euler formula transform method is proposed to convert trigonometric polynomials into algebraic polynomials,changing the zeros of the former into those of the latter.(C)Utilize the Fourier-Frobenius matrix method to solve the zeros of algebraic polynomials.To assess the computation time and accuracy,a turboprop aircraft with two six-bladed propellers was analyzed using the computational fluid dynamics and acoustic analogy method,providing acoustic pressure signals at 20 receivers for noise prediction and optimization.The Durand-Kerner and Fourier-Frobenius matrix methods were compared.Results demonstrate that improved propeller signatures theory is more accurate,and the Hessian matrix+Fourier-Frobenius matrix method is faster and more precise than the Hessian matrix+Durand-Kerner method.展开更多
Efficient torque allocation in over-actuated vehicles poses a central challenge in the domain of advanced vehicle control.These vehicles,featuring redundant actuators,provide an exceptional avenue for enhancing perfor...Efficient torque allocation in over-actuated vehicles poses a central challenge in the domain of advanced vehicle control.These vehicles,featuring redundant actuators,provide an exceptional avenue for enhancing performance,stability,and efficiency.This paper presents a pioneering tendency for torque allocation in the context of over-actuated vehicles,particularly inwheel motor(IWM)driven electric vehicles.We introduce a systematic methodology grounded in analytical modeling,allowing for the efficient reconciliation of multiple,often conflicting objectives.The explicit functions are analytically modeled to enhance stability and energy economy.Additionally,a fuzzy logic-based torque allocation strategy is developed and compared,along with other literature methods,with the analytical models.Simulations are conducted in a joint simulation between Simulink/MATLAB and SCANeR Studio vehicle dynamics simulator,followed by validation on a real-world dataset.Our findings elucidate the proficiency of the analytical models on vehicle performance,stability,computational efficiency,and energy consumption.展开更多
This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,t...This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,treated with the Fenton reaction for wet peroxidation,and separated by density separation.Analysis employed Focal Plane Array Micro-Fourier Transform Infrared Spectroscopy(FPA micro-FTIR),a widely used technique in MPs analysis,alongside the less common Laser Direct Infrared Spectroscopy(LDIR),providing complementary data on particle composition,shape,size,and colour.To enhance insights,spectroscopic methods were supplemented with Thermal Desorption Gas Chromatography-Mass Spectrometry(TD-GC/MS),calibrated for specific polymers,to quantify MPs by mass and assess removal efficiency.Wastewater treatment effectively reduced MPs.In influent samples,concentrations reached 72 MPs/L(FTIR),2117 MPs/L(LDIR),and 177μg/L(TD-GC/MS).Primary treatments removed 41%–55%,while the wastewater treatment plant effluent contained 1 MPs/L(FTIR),93 MPs/L(LDIR),and 2μg/L(TD-GC/MS),reflecting 96%–99%removal efficiency.Activated sludge showed concentrations of 123 MPs/L(FTIR),10,800 MPs/L(LDIR),and 0.3 mg/g dry weight(TD-GC/MS),underscoring its role in MPs capture.However,sludge dewatering released significant MPs into centrifuge rejected water:484 MPs/L(FTIR),23,000 MPs/L(LDIR),and 1100μg/L(TD-GC/MS).These results highlight the effectiveness of conventional treatments in MPs removal and the critical role of sludge in capturing these contaminants.However,sludge dewatering poses a risk of reintroducing MPs into the environment.Effective sludge management should prioritize nutrient recovery and biomass valorisation to mitigate these risks and minimise harmful environmental impacts.展开更多
Promoting urban-rural integration and facilitating the bidirectional flow of urban and rural elements are core spatial objectives in the new era of China.The urban-rural fringe represents the region with the most inte...Promoting urban-rural integration and facilitating the bidirectional flow of urban and rural elements are core spatial objectives in the new era of China.The urban-rural fringe represents the region with the most intense interaction between urban and rural areas,serving as a key zone for breaking down barriers and promoting urban-rural integration.Based on a systematic review of representative case studies and scholarly literature,this paper synthesizes the evolving research perspectives on the urban-rural fringe,with particular attention to how data-driven approaches that integrate official statistics,remote sensing imagery,points of interest,and mobile phone signaling data have advanced the characterization of fringe features,refined identification methods,and revealed emerging developmental trends through spatial clustering and machine learning classification.It proposes an integrated analytical framework encompassing administrative boundaries,economic metabolism,social activities,material infrastructure,and the ecological environment.The paper further examines the characteristics and emerging development trends of urban-rural fringe areas and advances a set of strategic directions to support urban-rural integration and more efficient resource allocation.These include expanding analytical dimensions,enhancing data integration,refining identification criteria,elucidating mechanisms of internal and external interactions,and strengthening interdisciplinary collaboration.Collectively,these efforts offer actionable insights for optimizing public service delivery,directing infrastructure investment in transportation and utilities,delineating ecological conservation boundaries,and implementing place-based socioeconomic revitalization strategies in the urban-rural fringe regions.展开更多
The intelligent environmental sensing systems are quickly transforming the sparse and retrospective monitoring to dense and decision-oriented environmental intelligence.This review brings together the manner in which ...The intelligent environmental sensing systems are quickly transforming the sparse and retrospective monitoring to dense and decision-oriented environmental intelligence.This review brings together the manner in which integration of Internet of Things(IoT)sensing,edge computing,and real-time analytics facilitates timely detection,interpretation,and prediction of the environmental conditions across the applications,such as urban air quality,watershed and coastal surveillance,industrial safety,agriculture,and disaster response.We define end-to-end architectural patterns to organize devices,edge nodes,and cloud services to satisfy latency,reliability,bandwidth,and governance constraints with emphasis on event-time processing,adaptive offloading,and hierarchical aggregation.Then we look at sensing and infrastructure foundations,emphasizing the effects of sensor modality and power autonomy,connectivity,and the practices of calibration on the practicable analytics and eventual plausibility.It is on this basis that we examine real-time analytics pipelines and Artificial Intelligence(AI)techniques to preprocess,sensor combine,anomaly detect,and short-horizon forecast,with a focus on edge-deployable models,quantification of uncertainties,and query resistance to drift and domain shift.Lastly,we address the realities of deployment that condition operational success,such as lifecycle engineering,provenance-aware data management,security and privacy risks,ethical governance,and evaluation methodologies,which place end-to-end latency and field generalization as a priority.This review offers cohesion to algorithmic capabilities and systems engineering and governance to define an overall framework,show open areas of research directions,and provide practical recommendations on how to design trustworthy,scalable,and sustainable environmental monitoring systems.展开更多
Chinese Chemical Letters(CCL)(ISSN 1001-8417)was founded in July 1990.The journal publishes preliminary accounts in the whole field of chemistry,including inorganic chemistry,organic chemistry,analytical chemistry,phy...Chinese Chemical Letters(CCL)(ISSN 1001-8417)was founded in July 1990.The journal publishes preliminary accounts in the whole field of chemistry,including inorganic chemistry,organic chemistry,analytical chemistry,physical chemistry,polymer chemistry,applied chemistry,etc.,satisfying a real and urgent need for the dissemination of research results,especially hot topics.The journal does not accept articles previously published or scheduled to be published.To verify originality,your article may be checked by the originality detection service Cross Check.展开更多
Oil-fired construction machinery(OCM)is a major source of urban air pollutants and CO_(2) emissions,and elec-trification is a crucial pathway for improving air quality and achieving China’s dual carbon goals;however,...Oil-fired construction machinery(OCM)is a major source of urban air pollutants and CO_(2) emissions,and elec-trification is a crucial pathway for improving air quality and achieving China’s dual carbon goals;however,its feasibility has not been fully explored.This study uses data envelopment analysis and the analytic hierarchy process to establish a development potential index,covering technical efficiency,economic cost,application sce-narios,and charging time and range,with an empirical analysis conducted in Beijing.The findings indicated the high feasibility of replacing OCM with electric alternatives,especially within the low-power range.Based on 2023 registered coding dat1,it is projected that by 2030,electrification could reduce regional average con-centrations of CO,NO_(x),PM_(2.5) and VOCs by 12.2%to 56.4%and reduce CO_(2) by 11.7%to 56.9%.Owing to economic considerations,small-and medium-sized machinery are particularly feasible for electrification.Key recommendations include prioritizing the electrification of forklifts,lifting platforms,and small-sized machinery in high-emission areas,particularly in central urban districts.Policies such as carbon taxes,carbon markets,and performance grading systems are suggested to incentivize electrification,along with expanding high-emission restriction zones and improving energy infrastructure to support widespread electrification.展开更多
Multimodal spatiotemporal data from smart city consumer electronics present critical challenges including cross-modal temporal misalignment,unreliable data quality,limited joint modeling of spatial and temporal depend...Multimodal spatiotemporal data from smart city consumer electronics present critical challenges including cross-modal temporal misalignment,unreliable data quality,limited joint modeling of spatial and temporal dependencies,and weak resilience to adversarial updates.To address these limitations,EdgeST-Fusion is introduced as a cross-modal federated graph transformer framework for context-aware smart city analytics.The architecture integrates cross-modal embedding networks for modality alignment,graph transformer encoders for spatial dependency modeling,temporal self-attention for dynamic pattern learning,and adaptive anomaly detection to ensure data quality and security during aggregation.A privacy-preserving federated learning protocol with differential privacy guarantees enables collaborative model training without centralizing sensitive data.The framework employs data-quality-aware weighted aggregation to enhance robustness against noisy and malicious client updates.Experimental evaluation on the GeoLife,PeMS-Bay,and SmartHome+datasets demonstrates that EdgeST-Fusion achieves 21.8%improvement in prediction accuracy,35.7%reduction in communication overhead,and 29.4%enhancement in security resilience compared to recent baselines.Real-world deployment across three smart city testbeds validates practical viability with 90.0%average accuracy and sub-250 ms inference latency.The proposed framework remains feasible for deployment on heterogeneous and resource-constrained consumer electronics devices whilemaintaining strong privacy guarantees and scalability for large-scale urban environments.展开更多
基金Supported by the Project of International Cooperation between China and U kraine(No.0 4 3- 0 5 ) and the Project ofKJCXGC- 0 1Northwest Norm al U niversityChina
文摘A new analytical method is proposed for the determination of heroin based on a sequential perturbation caused by trace amounts of heroin in the Cu(Ⅱ)-catalyzed oscillating reaction between hydrogen peroxide and sodium thiocyanate in an alkaline medium with the aid of a continuous-flow stirred tank reactor(CSTR). The method relies on the linear relationship between the change in oscillation period of the system and the concentration of heroin, with a detecting limit of 4.0×10^(-7) mol/L. The calibration curve fits a linear equation very well when the concentration of heroin is in the range of 2.0×10^(-6)_1.2×10^(-5) mol/L(r=0.9971). This method features good precision(RSD=0.98%). The influences of temperature, injection point, flow rate and reaction variables on the oscillation period were investigated in detail and a possible mechanism of the performance of heroin in the Cu(Ⅱ)-catalyzed oscillating reaction system is also discussed. The proposed method opens a new avenue for the determination of heroin.
文摘The aim of the present investigation was to develop a biosensor for the detection of amino acids, Leucine, Isoleucine and Valine based on a quartz crystal nanobalance. leucine (Leu), isoleucine (Ile), and valine (Val) were selectively determined by quartz crystal nanobalance (QCN) sensor in conjunction with net analyte signal (NAS)-based method called HLA/GO. An orthogonal design was applied for the formation of calibration and prediction sets including Leu, Ile and Val compounds. The selection of the optimal time range involved the calculation of the net analyte sig-nal regression plot in any considered time window for each test sample. The searching of a region with maximum linearity of NAS regression plot (minimum error indicator) and minimum of PRESS value was carried out by applying a moving window strategy. On the base of obtained results, the differences on the adsorption profiles in the time range between 1 and 300 s were used to determine mixtures of compounds by HLA/GO method. The results showed that the method was successfully applied for the determina-tion of Leu, Ile and Val.
基金National Natural Science Foundation of China(Nos.92050203,52122511,52305319,52375582)Shenzhen Fundamental Research Program(Nos.JCYJ20200109105606426,JCYJ20190808164007485)。
文摘Surface-enhanced Raman scattering(SERS)platform,which enables trace analyte detection,has important application prospects.By structuring/modifying the surface of the SERSsubstrate,analyte in highly diluted solutions can be concentrated into localized active areas for highly sensitive detection.However,subject to the difficulty of the fabrication process,itremains challenging to balance hot-spot construction and the concentration capacity of analyte simultaneously.Therefore,preparing SERS substrates with densely ordered hot spots andefficient concentration capacity is of great significance for highly sensitive detection.Herein,we propose an Ag and fluoroalkyl-modified hierarchical armour substrate(Ag/F-HA),which has a double-layer stacking design to combine analyte concentration with hotspot construction.The microarmour structure is fabricated by femtosecond-laser processing to serve as asuperhydrophobic and low-adhesive surface to concentrate analyte,while the anodic aluminium oxide(AAO)template creates a nanopillar array serving as dense and ordered hot spots.Under the synergistic action of hot spots and analyte concentration,Ag/F-HA achieves a detectionlimit down to 10^(-7)M doxorubicin(DOX)molecules with a RSD of 7.69%.Additionally,Ag/F-HA exhibits excellent robustness to resist external disturbances such as liquid splash or abrasion.Based on our strategy,SERS substrates with directional analyte concentrations are further explored by patterning microcone arrays with defects.This work opens a way to the realistic implementation of SERS in diverse scenarios.
文摘DETECHIP is a detection system made of various sensors that has been shown to detect and discriminate between small molecules of interest, including various illicit and over-the-counter drugs. Previously, detection was normalized to a single concentration of analyte. Now this detection assay can detect concentration differences in analytes via red, green, and blue color value changes and shifts in the UV-Vis spectra of the assay. To determine the concentrations differences, the exposed assays were scanned on a flatbed scanner and the images were analyzed for individual RGB values with a custom macro in ImageJ, an image analysis program. Increasing concentrations of the analyte resulted in greater differences in color values between control and analyte wells. These differences showed a linear relationship to concentration change, some with correlation coefficients greater than 98%. This work expands the capability of DETECHIP to give information about the concentration of analyte when the analyte identity is known.
文摘A novel method for simultaneous determination of kolliphor HS15 and miglyol 812 in microemulsion formulation was developed using ultra-high performance liquid chromatography coupled with a nano quantitation analytical detector （UHPLC-NQAD）. All components in kolliphor HS15 and miglyo1812 were well separated on an Acquity BEH C18 column. Mobile phase A was 0.1% trifluoroacetic acid （TFA） in water and mobile phase B was acetonitrile. A gradient elution sequence was programed initially with 60% organic solvent, slowly increased to 100% within 8 min. The flow rate was 0.7 mL/min. Good linearity （r 〉 0.95） was obtained in the range of 27.6-1381.1 μg/mL for polyoxyl 15 hydroxystearate in kolliphor HS15, 0.8-202.0 μg/mL for caprylic acid triglyceride and 2.7-221.9μg/mL for capric acid triglyceride in miglyol 812. The relative standard deviations （RSD） ranged from 0.6% to 1.7% for intra-day precision and from 0.4% to 2.7% for inter-day precision. The overall recoveries （accuracy） were 99.7%-101.4% for polyoxyl 15 hydroxystearate in kolliphor HS15, 96.7%-99.6% for caprylic acid triglyceride, and 94.1%- 103.3% for capric acid triglyceride in miglyol 812. Quantification limits （QL） were determined as 27.6 μg/ mL for polyoxy115 hydroxystearate in kolliphor HS15, 0.8 μg/mL for caprylic acid triglyceride, and 2.7 μg/ mL for capric acid triglyceride in miglyol 812. No interferences were observed in the retention time ranges of kolliphor HSI5 and miglyol 812. The method was validated in terms of specificity, linearity, precision, accuracy, QL, and robustness. The proposed method has been applied to microemulsion for- mulation analyses with good recoveries （82.2%-103.4%）.
基金support for this work was obtained from SERB through grant no.CRG/2021/000080 and EEQ/2021/000013.
文摘Sulfur is a soft Lewis base and thiocarbonyl has moderate electrophilicity.Our probe’s properties are adjusted in such a way that it could simultaneously detect a Lewis acid(Hg^(2+))and a strong nucleophile(NH_(2)-NH_(2)).Considering the above fact,a thioureido-functionalized robust MOF material was prepared,which was utilized for the selective fluorometric detection of environmentally significant toxic pollutants(Hg^(2+)and NH_(2)-NH_(2))in an aqueous medium.
文摘Voltammetric analytical techniques combine exceptional sensitivity,low cost,portability and capability for simultaneous determination of multiple analytes.The sensitivity of voltammetric analysis is largely determined by the efficiency of the working electrode.Electrodes modified with metal organic frameworks(MOFs)seem particularly promising for use in the analysis of a series of important inorganic and organic analytes.Nevertheless,research on chemically modified electrodes with MOFs is still in its infancy.In this critical review,we present the current status of research related to MOF-modified electrodes highlighting the respective MOF-modified electrodes which are based on MOFs that show exceptional chemical stability or/and sorption capability towards the targeted analytes.We also provide perspectives for future research aiming at motivating additional scientists to be involved in this exciting field of MOF-based electroanalytical sensors.
基金support from the National Natural Sci-ence Foundation of China(grant nos.T2225010,32171399,and 32171456)Guangdong Basic and Applied Basic Research Foundation(grant no.2023A1515011267)+1 种基金Science and Technalogy Program of Guangzhou,China(grant nos.2024B03J0121 and 2024B03J1284)the Independent Fund of the State Key Laboratory of Optoelectronic Ma-terials and Technologies(Sun YatSen University)under grant no.
文摘Monitoring multiplexed biochemical markers is beneficial for the comprehensive evaluation of diabetes-associated complications.Techniques for multiplexed analyses in interstitial fluids have often been restricted by the difficulties of electrode materials in accurately detecting chemicals in complex subcutaneous spaces.In particular,the signal stability of enzyme-based sensing electrodes often inevitably decreases due to enzyme degradation or interference in vivo.In this study,we developed a self-calibrating multiplexed microneedle(MN)electrode array(SC-MMNEA)capable of continuous,real-time monitoring of multiple types of bioanalytes(glucose,cholesterol,uric acid,lactate,reactive oxygen species[ROSs],Na+,K+,Ca2+,and pH)in the subcutaneous space.Each type of analyte was detected by a discrete MN electrode assembled in an integrated array with single-MN resolution.Moreover,this device utilized an MN-delivery-mediated self-calibration technique to address the inherent problem of decreased accuracy of implantable electrodes caused by long-term tissue variation and enzyme degradation,and this technique might increase the reliability of the MN sensors.Our results indicated that SC-MMNEA could provide real-time monitoring of multiplexed analyte concentrations in a rat model with good accuracy,especially after self-calibration.SC-MMNEA has the advantages of in situ and minimally invasive monitoring of physiological states and the potential to promote wearable devices for long-term monitoring of chemical species in vivo.
基金support of the Ministry of Electronics and Information Technology,Government of India(Grant number W-49/3/2019-IPHWMeitY)is acknowledged。
文摘A wearable multiplex sweat sensing patch with low sweat volume requirement and uniform distribution is highly desirable for noninvasive,real-time monitoring of various health-related biomarkers.The patch features a multi-channel microfluidic system inspired by cnidarians.It comprises of symmetric super-hydrophilic/super-hydrophobic patterned wedge channels allowing for simultaneous analysis of multiple analytes present in sweat.It ensures a uniform sweat transport and equal volume distribution across multiple sensing zones for a more accurate and reliable electrochemical sensing.As a proof of concept,a four-channel system housing sensors for glucose,lactate,urea,and pH was tested.The innovation lies in a unique surface design and electrode configuration utilizing PDMS-TiO_(2)nanocomposite coating,integrating channels with electrodes,presenting a novel approach for accurate low-volume sweat analysis requiring a minimum of 4µL.An on-body test was conducted to demonstrate the practical application of the patch.In addition,the physics of droplet splitting was explained through simulations.
基金supported by the National Natural Science Foundation of China (31770055, 31922002, 31720103901, and 31772242)the 111 Project (B18022)+4 种基金the Fundamental Research Funds for the Central Universities (22221818014)the Shanghai Science and Technology Commission (18JC1411900)the Young Scientists Innovation Promotion Association of Chinese Academy of Sciences (2016087) to Weishan Wangthe Shandong Taishan Scholar Program of China to Lixin Zhangthe Open Project Funding of the State Key Laboratory of Bioreactor Engineering
文摘Rapid and sensitive detection of various analytes is in high demand.Apart from its application in genome editing,CRISPR-Cas also shows promises in nucleic acid detection applications.To further exploit the potential of CRISPR-Cas for detection of diverse analytes,we present a versatile biosensing platform that couples the excellent affinity of aptamers for broad-range analytes with the collateral single-strand DNA cleavage activity of CRISPR-Cas12 a.We demonstrated that the biosensors developed by this platform can be used to detect protein and small molecule in human serum with a complicated background,i.e.,the tumor marker alpha fetoprotein and cocaine with the detection limits of 0.07 fmol/L and 0.34 lmol/L,respectively,highlighting the advantages of simplicity,sensitivity,short detection time,and low cost compared with the state-of-the-art biosensing approaches.Altogether,this biosensing platform with plug-and-play design show great potential in the detection of diverse analytes.
文摘This paper deals with carbon emissions reduction through building material selection in housing construction using Analytical Hierarchy Process(AHP)method.Drawing on the concept of Sustainable Development in the Environment(SDE),inadequate selection of building materials makes a significant contribution to carbon emissions.The achievability of the goal of SDE is in rethinking Locally Sourced and Recycled Building Materials(LSRBMs)selection decision making,in acknowledging cultural issues,towards the wider industrial use of Recycled Concrete Crushed Block Wall(RCCBW)which is about 66%,in carbon emissions,as good as Air-crete Hollow Block Wall(AHBW).With results derived from questionnaire survey with recruited civil engineers and architects,key sustainability principle indicators influencing the selection of building materials are identified,analysed,grouped and ranked using AHP,a concept of measurement through pairwise comparisons of tangible and intangible factors to derive priority scales in relative terms.This explained 17.27%cut back in carbon emissions for selecting Compressed Stabilized Rammed-Earth Block Wall(CSREBW)instead of AHBW.The lack of informed knowledge in the wider use of RCCBW and CSREDW and in the Ghanaian context towards future reduction in carbon emissions in the housing sector of the construction industry of Ghana.Subsequently,the study yielded the following theoretical,practical and policy implications:A new interpretation of existing building materials;Understanding the impact of building materials’attributes;In effect,might be beneficial to universities and organizations to come up with training policies that aim to take advantage of the new technology respectively.
基金supported by the National Natural Science Foundation of China(Nos.51576097,51976089)the Funding for Outstanding Doctoral Dissertation in Nanjing University of Aeronautics and Astronautics,China(No.BCXJ24-05)the Aeronautical Science Foundation of China(No.2023L060052001).
文摘Quick and accurate determination of the optimal synchrophase angle is crucial for synchrophasing control of multi-propeller aircraft with low noise.This paper proposes a novel noise prediction and optimization strategy,developing a continuous and accurate noise prediction model and obtaining its minimum by solving the Hessian matrix and Fourier-Frobenius matrix.Firstly,a novel propeller noise prediction method uses acoustic simulation pressure signals and improved propeller signatures theory to accurately estimate noise for all synchrophase angles and receiving points.Secondly,a novel optimization approach is proposed to solve the analytical solution of the minimum propeller noise:(A)A noise objective function is established,and use its first derivatives’zeros and Hessian matrix to determine the function minimum.(B)A novel Euler formula transform method is proposed to convert trigonometric polynomials into algebraic polynomials,changing the zeros of the former into those of the latter.(C)Utilize the Fourier-Frobenius matrix method to solve the zeros of algebraic polynomials.To assess the computation time and accuracy,a turboprop aircraft with two six-bladed propellers was analyzed using the computational fluid dynamics and acoustic analogy method,providing acoustic pressure signals at 20 receivers for noise prediction and optimization.The Durand-Kerner and Fourier-Frobenius matrix methods were compared.Results demonstrate that improved propeller signatures theory is more accurate,and the Hessian matrix+Fourier-Frobenius matrix method is faster and more precise than the Hessian matrix+Durand-Kerner method.
基金carried out within the framework of the V3EA Project“Electric,Energy Efficient,and Autonomous Vehicle”(2021-2025)supported by the Research National Agency(ANR)of the French Government。
文摘Efficient torque allocation in over-actuated vehicles poses a central challenge in the domain of advanced vehicle control.These vehicles,featuring redundant actuators,provide an exceptional avenue for enhancing performance,stability,and efficiency.This paper presents a pioneering tendency for torque allocation in the context of over-actuated vehicles,particularly inwheel motor(IWM)driven electric vehicles.We introduce a systematic methodology grounded in analytical modeling,allowing for the efficient reconciliation of multiple,often conflicting objectives.The explicit functions are analytically modeled to enhance stability and energy economy.Additionally,a fuzzy logic-based torque allocation strategy is developed and compared,along with other literature methods,with the analytical models.Simulations are conducted in a joint simulation between Simulink/MATLAB and SCANeR Studio vehicle dynamics simulator,followed by validation on a real-world dataset.Our findings elucidate the proficiency of the analytical models on vehicle performance,stability,computational efficiency,and energy consumption.
基金the Italian Ministry of Universities and Research for funding his PhD scholarship(37th Cycle Ph D Programmes supported by ESF REACT-EU funds,National Operational Programme on Research and Innovation)CSGI(Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase-Center for Colloid and Surface Science),Florence(Italy)for financial support.
文摘This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,treated with the Fenton reaction for wet peroxidation,and separated by density separation.Analysis employed Focal Plane Array Micro-Fourier Transform Infrared Spectroscopy(FPA micro-FTIR),a widely used technique in MPs analysis,alongside the less common Laser Direct Infrared Spectroscopy(LDIR),providing complementary data on particle composition,shape,size,and colour.To enhance insights,spectroscopic methods were supplemented with Thermal Desorption Gas Chromatography-Mass Spectrometry(TD-GC/MS),calibrated for specific polymers,to quantify MPs by mass and assess removal efficiency.Wastewater treatment effectively reduced MPs.In influent samples,concentrations reached 72 MPs/L(FTIR),2117 MPs/L(LDIR),and 177μg/L(TD-GC/MS).Primary treatments removed 41%–55%,while the wastewater treatment plant effluent contained 1 MPs/L(FTIR),93 MPs/L(LDIR),and 2μg/L(TD-GC/MS),reflecting 96%–99%removal efficiency.Activated sludge showed concentrations of 123 MPs/L(FTIR),10,800 MPs/L(LDIR),and 0.3 mg/g dry weight(TD-GC/MS),underscoring its role in MPs capture.However,sludge dewatering released significant MPs into centrifuge rejected water:484 MPs/L(FTIR),23,000 MPs/L(LDIR),and 1100μg/L(TD-GC/MS).These results highlight the effectiveness of conventional treatments in MPs removal and the critical role of sludge in capturing these contaminants.However,sludge dewatering poses a risk of reintroducing MPs into the environment.Effective sludge management should prioritize nutrient recovery and biomass valorisation to mitigate these risks and minimise harmful environmental impacts.
基金Under the auspices of the Funding Project of Northeast Geological S&T Innovation Center of China Geological Survey(No.QCJJ2024-11)Natural Science Foundation of Liaoning Province(No.2025-BS-0873)+1 种基金Liaoning Provincial Joint Science and Technology Program(No.2024-MSLH-507)National Social Science Foundation of China(No.23ATJ006)。
文摘Promoting urban-rural integration and facilitating the bidirectional flow of urban and rural elements are core spatial objectives in the new era of China.The urban-rural fringe represents the region with the most intense interaction between urban and rural areas,serving as a key zone for breaking down barriers and promoting urban-rural integration.Based on a systematic review of representative case studies and scholarly literature,this paper synthesizes the evolving research perspectives on the urban-rural fringe,with particular attention to how data-driven approaches that integrate official statistics,remote sensing imagery,points of interest,and mobile phone signaling data have advanced the characterization of fringe features,refined identification methods,and revealed emerging developmental trends through spatial clustering and machine learning classification.It proposes an integrated analytical framework encompassing administrative boundaries,economic metabolism,social activities,material infrastructure,and the ecological environment.The paper further examines the characteristics and emerging development trends of urban-rural fringe areas and advances a set of strategic directions to support urban-rural integration and more efficient resource allocation.These include expanding analytical dimensions,enhancing data integration,refining identification criteria,elucidating mechanisms of internal and external interactions,and strengthening interdisciplinary collaboration.Collectively,these efforts offer actionable insights for optimizing public service delivery,directing infrastructure investment in transportation and utilities,delineating ecological conservation boundaries,and implementing place-based socioeconomic revitalization strategies in the urban-rural fringe regions.
基金supported by Jiangxi Polytechnic Institute Key Research Topics in Educational Reform 2025-JGJG-07.
文摘The intelligent environmental sensing systems are quickly transforming the sparse and retrospective monitoring to dense and decision-oriented environmental intelligence.This review brings together the manner in which integration of Internet of Things(IoT)sensing,edge computing,and real-time analytics facilitates timely detection,interpretation,and prediction of the environmental conditions across the applications,such as urban air quality,watershed and coastal surveillance,industrial safety,agriculture,and disaster response.We define end-to-end architectural patterns to organize devices,edge nodes,and cloud services to satisfy latency,reliability,bandwidth,and governance constraints with emphasis on event-time processing,adaptive offloading,and hierarchical aggregation.Then we look at sensing and infrastructure foundations,emphasizing the effects of sensor modality and power autonomy,connectivity,and the practices of calibration on the practicable analytics and eventual plausibility.It is on this basis that we examine real-time analytics pipelines and Artificial Intelligence(AI)techniques to preprocess,sensor combine,anomaly detect,and short-horizon forecast,with a focus on edge-deployable models,quantification of uncertainties,and query resistance to drift and domain shift.Lastly,we address the realities of deployment that condition operational success,such as lifecycle engineering,provenance-aware data management,security and privacy risks,ethical governance,and evaluation methodologies,which place end-to-end latency and field generalization as a priority.This review offers cohesion to algorithmic capabilities and systems engineering and governance to define an overall framework,show open areas of research directions,and provide practical recommendations on how to design trustworthy,scalable,and sustainable environmental monitoring systems.
文摘Chinese Chemical Letters(CCL)(ISSN 1001-8417)was founded in July 1990.The journal publishes preliminary accounts in the whole field of chemistry,including inorganic chemistry,organic chemistry,analytical chemistry,physical chemistry,polymer chemistry,applied chemistry,etc.,satisfying a real and urgent need for the dissemination of research results,especially hot topics.The journal does not accept articles previously published or scheduled to be published.To verify originality,your article may be checked by the originality detection service Cross Check.
基金supported by the National Science and Technology Major Project of the Ministry of Science and Technology of China(No.2024ZD1200200).
文摘Oil-fired construction machinery(OCM)is a major source of urban air pollutants and CO_(2) emissions,and elec-trification is a crucial pathway for improving air quality and achieving China’s dual carbon goals;however,its feasibility has not been fully explored.This study uses data envelopment analysis and the analytic hierarchy process to establish a development potential index,covering technical efficiency,economic cost,application sce-narios,and charging time and range,with an empirical analysis conducted in Beijing.The findings indicated the high feasibility of replacing OCM with electric alternatives,especially within the low-power range.Based on 2023 registered coding dat1,it is projected that by 2030,electrification could reduce regional average con-centrations of CO,NO_(x),PM_(2.5) and VOCs by 12.2%to 56.4%and reduce CO_(2) by 11.7%to 56.9%.Owing to economic considerations,small-and medium-sized machinery are particularly feasible for electrification.Key recommendations include prioritizing the electrification of forklifts,lifting platforms,and small-sized machinery in high-emission areas,particularly in central urban districts.Policies such as carbon taxes,carbon markets,and performance grading systems are suggested to incentivize electrification,along with expanding high-emission restriction zones and improving energy infrastructure to support widespread electrification.
基金supported by the University of Tabuk,Saudi Arabia。
文摘Multimodal spatiotemporal data from smart city consumer electronics present critical challenges including cross-modal temporal misalignment,unreliable data quality,limited joint modeling of spatial and temporal dependencies,and weak resilience to adversarial updates.To address these limitations,EdgeST-Fusion is introduced as a cross-modal federated graph transformer framework for context-aware smart city analytics.The architecture integrates cross-modal embedding networks for modality alignment,graph transformer encoders for spatial dependency modeling,temporal self-attention for dynamic pattern learning,and adaptive anomaly detection to ensure data quality and security during aggregation.A privacy-preserving federated learning protocol with differential privacy guarantees enables collaborative model training without centralizing sensitive data.The framework employs data-quality-aware weighted aggregation to enhance robustness against noisy and malicious client updates.Experimental evaluation on the GeoLife,PeMS-Bay,and SmartHome+datasets demonstrates that EdgeST-Fusion achieves 21.8%improvement in prediction accuracy,35.7%reduction in communication overhead,and 29.4%enhancement in security resilience compared to recent baselines.Real-world deployment across three smart city testbeds validates practical viability with 90.0%average accuracy and sub-250 ms inference latency.The proposed framework remains feasible for deployment on heterogeneous and resource-constrained consumer electronics devices whilemaintaining strong privacy guarantees and scalability for large-scale urban environments.
