Power Optimization Cooperative Control Strategy for Flexible Fast Interconnection Device with Energy Storage

With the wide application of renewable energy power generation technology,the distribution network presents the characteristics of multi-source and complex structure.There are potential risks in the stability of power system,and the problem of power quality is becoming more and more serious.This paper studies and proposes a power optimization cooperative control strategy for flexible fast interconnection device with energy storage,which combines the flexible interconnection technology with the energy storage device.The primary technology is to regulate the active and reactive power of the converter.By comparing the actual power value of the converter with the reference value,the proportional integral(PI)controller is used for correction,and the current components of d and q axes are obtained and input to the converter as the reference value of the current inner loop.The control strategy in this paper can realize power mutual aid between feeders,and at the same time,the energy storage device can provide or absorb a certain amount of power for feeders,so that the power grid can realize stable operation in a certain range.

Understanding the growth mechanisms of metal-based core–shell nanostructures revealed by in situ liquid cell transmission electron microscopy

Metal-based core-shell nanostructures have garnered enduring interest due to their unique properties and functionalities.However,their growth and transformation mechanisms in liquid media remain largely unknown because they lack direct observation of the dynamic growth process with high spatial and temporal resolution.Developing the in situ liquid cell transmission electron microscopy(TEM)technique offers unprecedented real-time imaging and spectroscopy capabilities to directly track the evolution of structural and chemical transformation of metal-based core–shell nanostructures in liquid media under their working condition.Here,this review highlights recent progress in utilizing in situ liquid cell TEM characterization technique in investigating the dynamic evolution of material structure and morphology of metal-based core–shell nanostructures at the nano/atomic scale in real-time.A brief introduction of the development of liquid cells for in situ TEM is first given.Subsequently,recent advances in in situ liquid cell TEM for the fundamental study of growth mechanisms of metal based core–shell nanostructures are discussed.Finally,the challenge and future developments of metalbased core–shell nanostructures for in situ liquid cell TEM are proposed.Our review is anticipated to inspire ongoing interest in revealing unseen growth dynamics of core–shell nanostructures by in situ liquid cell TEM technique.

Differences in the system accuracy acceptability of four types of blood glucose monitoring systems against five different standards

Objective:This study aimed to evaluate the system accuracy of four types of blood glucose monitoring systems(BGMSs)and explore the differences in the system accuracy acceptability of each BGMS against five different standards.Methods:The glucose measurement values obtained from four types of BGMSs(Roche Accu-Chek® Performa,Bayer Contour™TS,Sinomedisite Glupad® H1 Plus,and SinocareR Gold-Accu)were evaluated against the reference values obtained from the biochemical analyzer of the central laboratory.The system accuracy acceptability of each BGMS was determined using the criteria specified in five standards,namely the International Organization for Standardization(ISO)15197:2003,Clinical Laboratory Standards Institute(CLSI)POCT12-A3,ISO 15197:2013,Chinese Society of Laboratory Medicine(CSLM)consensus,and US Food and Drug Administration(FDA)guidelines.Results:From 2018 to 2022,10,980 pairs of measurement values were obtained from 366 glucose meters of four types of BGMSs.Significant correlations were observed between the glucose measurement values from the BGMSs and the reference values from the biochemical analyzer of the central laboratory.The correlation coefficient r was 0.995 for Roche Accu-Chek® Performa,0.994 for Bayer Contour™TS,0.983 for Sinomedisite Glupad® H1 Plus,and 0.997 for SinocareR Gold-Accu.The acceptability criteria specified in ISO 15197:2003 were met by 100.00%(135/135)of the glucose meters of Roche Accu-Chek® Performa,100.00%(109/109)of Bayer Contour™TS,81.61%(71/87)of Sinomedisite Glupad® H1 Plus,and 100.00%(35/35)of SinocareR Gold-Accu.Whereas,the acceptability criteria specified in ISO 15197:2013 were met by 99.26%(134/135)of the glucose meters of Roche Accu-Chek® Performa,88.07%(96/109)of Bayer Contour™TS,58.62%(51/87)of Sinomedisite Glupad R H1 Plus,and 91.43%(32/35)of SinocareR Gold-Accu.Conclusions:Among the four types of BGMSs evaluated,the glucose meters of Roche Accu-Chek® Performa exhibited superior system accuracy.The system accuracy acceptability of each BGMS varied significantly against the acceptability criteria specified in the five different standards.

Supercritical fluid-assisted fabrication of C-doped Co_(3)O_(4) nanoparticles based on polymer-coated metal salt nanoreactors for efficient enzyme-mimicking and glucose sensor properties

Nanomaterials doped with non-metallic C have attracted tremendous attention as potential nano-artificial enzymes due to their ability to change the energy band structure to improve their intrinsic properties.Herein,we report a green,facile,efficient,fast strategy to access high-performance nanozymes via supercritical CO_(2)fluid technology-fabricated polymer nanoreactor of poly-(methyl vinyl ether-co-maleic anhydride)(PVM/MA)coated Co(NO_(3))_(2)into C-doped Co_(3)O_(4)(C-Co_(3)O_(4))nanozyme by a onestep calcination process.Converting PVM/MA to C doping into Co_(3)O_(4)shortens the entire lattice constant of the crystal structure,and the overall valence band energy level below the Fermi level shifts toward the lower energy direction.The as-prepared CCo_(3)O_(4)demonstrated significant peroxidase-like catalytic activity,significantly greater than the undoped Co_(3)O_(4)nanoparticle nanozyme.The following density functional theory(DFT)calculations revealed that the doped nano-enzyme catalytic site displayed a unique electronic structure,altering the material surface with more electrons to fill the anti-bond of the two molecular orbitals,significantly improving the peroxidase-like enzyme catalytic and glucose sensor performance.The resultant enzymatic glucose sensing in a linear range of 0.1–0.6 mM with a detection limit of 3.86μM is in line with standard Michaelis–Menten theory.Collectively,this work demonstrates that converting polymers into nanozymes of C-doped form by supercritical CO_(2)fluid technology in a step is an effective strategy for constructing high-performance glucose sensor nanozymes.This cost-effective,reliable,precise system offers the potential for rapid analyte detection,facilitating its application in a variety of fields.

Atomic mechanisms of hexagonal close-packed Ni nanocrystallization revealed by in situ liquid cell transmission electron microscopy

The fundamental understanding of the mechanism underlying the early stages of crystallization of hexagonal-close-packed(hcp)nanocrystals is crucial for their synthesis with desired properties,but it remains a significant challenge.Here,we report using in situ liquid cell transmission electron microscopy(TEM)to directly capture the dynamic nucleation process and track the real-time growth pathway of hcp Ni nanocrystals at the atomic scale.It is demonstrated that the growth of amorphous-phase-mediated hcp Ni nanocrystals is from the metal-rich liquid phases.In addition,the reshaped preatomic facet development of a single nanocrystal is also imaged.Theoretical calculations further identify the non-classical features of hcp Ni crystallization.These discoveries could enrich the nucleation and growth model theory and provide useful information for the rational design of synthesis pathways of hcp nanocrystals.