The Medium-energy Electron Spectrometers(MES)is a space-borne instrument onboard Macao Science Satellite-1(MSS-1)dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit an...
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The Medium-energy Electron Spectrometers(MES)is a space-borne instrument onboard Macao Science Satellite-1(MSS-1)dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit and the process of their occurrence and development,including short bursts of lightning-induced electron precipitation(LEP).This paper presents the first results of the LEP measurements by the MSS-1.47 LEP events are identified with the routine operation for 3 months since satellite launch,all within the range of 1.5
An umbilic-free hypersurface in the unit sphere is called MSbius isoparametric if it satisfies two conditions, namely, it has vanishing MSbius form and has constant MSbius principal curvatures. In this paper, under th...
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An umbilic-free hypersurface in the unit sphere is called MSbius isoparametric if it satisfies two conditions, namely, it has vanishing MSbius form and has constant MSbius principal curvatures. In this paper, under the condition of having constant MSbius principal curvatures, we show that the hypersurface is of vanishing MSbius form if and only if its MSbius form is parallel with respect to the Levi-Civita connection of its MSbius metric. Moreover, typical examples are constructed to show that the condition of having constant MSbius principal curvatures and that of having vanishing MSbius form are independent of each other.
In this paper, continuing with hu-Li Vrancken and the recent work of Antid Dillen- Schoels-Vrancken, we obtain a decomposition theorem which settled the problem of how to determine whether a given locally strongly con...
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In this paper, continuing with hu-Li Vrancken and the recent work of Antid Dillen- Schoels-Vrancken, we obtain a decomposition theorem which settled the problem of how to determine whether a given locally strongly convex aitine hypersurface can be decomposed as a generalized Calabi composition of two affine hyperspheres, based on the properties of its difference tensor K and its affine shape operator S.
Using the Polar ultraviolet imager(UVI)above the Arctic and the all-sky camera(ASC)at Chinese Zhongshan Station(ZHS)in Antarctica,an outstanding hemispheric conjugate observation of postnoon"bright spots"in the Arctic...
Using the Polar ultraviolet imager(UVI)above the Arctic and the all-sky camera(ASC)at Chinese Zhongshan Station(ZHS)in Antarctica,an outstanding hemispheric conjugate observation of postnoon"bright spots"in the Arctic and auroral spirals in Antarctica is *** bright auroral spirals,which are counterclockwise rotation viewed along the direction of the magnetic field,in postnoon auroral arcs are seen on the filed of view(FOV)of ASC at ZHS in the southern hemisphere while multiple"bright spots"are seen at the conjugate FOV of ASC on postnoon auroral oval in the northern hemisphere by Polar *** consider that the auroral spirals in postnoon arcs are the visible characteristic of postnoon UV"bright spots"on ground-based observation,and suggest that the current sheet instability above the parallel electric field region,which could produce the arcs,is the origin for"bright spots"occurring at the ionosphere,and the hemispheric symmetry/asymmetry of postnoon upward FACs,which is affected by the IMF By and season,can control the conjugacy/non-conjugacy of postnoon"bright spots"/auroral spirals between the two hemispheres.
To elucidate the mechanisms of regulating the microstructure uniformity in 7050 aluminum forgings through surface cumulative plastic deformation(SCPD),the microstructure under different solution treatments was investi...
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To elucidate the mechanisms of regulating the microstructure uniformity in 7050 aluminum forgings through surface cumulative plastic deformation(SCPD),the microstructure under different solution treatments was investigated using metallographic observation(OM),electron backscatter diffraction(EBSD),transmission electron microscopy(TEM),and X-ray diffraction(XRD).The findings demonstrate that the most uniform microstructure in the forgings is achieved with a solution treatment at 470℃for 30 *** SCPD process generates a significant number of needle-shaped precipitates,resulting in a higher dislocation density and stored *** treatments alleviate the pinning effect of second-phase particles and facilitate static recrystallization(SRX)in forgings,leading to a reduction in grain ***,mechanical testing results demonstrate 7%−13%increase in tensile strength and more uniform elongation of the forgings in different directions.
The quest for efficient and durable catalysts using abundant resources has garnered significant interest in the field of bifunctional oxygen *** this contribution,we have designed a FeN4or CoN4embedded graphene-based ...
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The quest for efficient and durable catalysts using abundant resources has garnered significant interest in the field of bifunctional oxygen *** this contribution,we have designed a FeN4or CoN4embedded graphene-based bilayer as active layer and TMC3or TMN3doped graphene as supporting layer,named as FeN4/TMC3or FeN4/TMN3and CoN4/TMC3or CoN4/TMN3,wherein TM strands for transition *** on density functional theory calculations,our results demonstrate that the interaction formed between dual metal atoms in the bilayer interspace leads to the coordination environment altered from flat four-coordination to spatial five-coordination,further stabilizing the bilayer structure and impairing its affinity toward the O-containing *** to thermodynamic analysis,the bilayers of CoN4/CoN3,FeN4/FeC3,FeN4/CoC3,FeN4/NiC3,FeN4/ZnC3,FeN4/FeN3,FeN4/CrN3and FeN4/ZnN3are attractively promising for bifunctional oxygen electrocatalysis due to the small overpotential differenceΔη between oxygen reduction and oxygen evolution that are less than 1 *** functional theory calculations combined with machine learning analysis directly identify the key role played by the interbinding formed between bilayers,that boosts catalytic activity,which establishes a predictable framework for a fast screen for graphene-based bilayer vertical *** work opens up a new path for designing the efficient electrocatalysts via modification of coordination environment.
Various data were utilized to analyze the sedimentary facies,completely reconstruct the palaeogeographic maps,and evaluate the reservoir quality of the Middle-Upper Cambrian Xixiangchi Formation in the Sichuan Basin,i...
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Various data were utilized to analyze the sedimentary facies,completely reconstruct the palaeogeographic maps,and evaluate the reservoir quality of the Middle-Upper Cambrian Xixiangchi Formation in the Sichuan Basin,including evidence from field outcrops,drilling cores,microscopic thin sections,scanning electron microscopy （SEM）,combined with experimental analysis data,such as petrophysical data(porosity （%） and permeability （mD）),and radioactive elements (uranium (238U),thorium (232Th),and potassium (40K)),and isotopic data (δ13C)).In the Sichuan Basin,the Middle-Upper Cambrian Xixiangchi Formation was principally deposited in a restricted platform with a lithology predominantly composed of dolomite,with local occurrences of limestone and other rock types in small *** beddings,cross beddings,horizontal beddings,storm depositions,and mud cracks locally developed in some *** 3rd-order sequences （SQ1-SQ4） were identified within the Xixiangchi Formation in this *** sequence is subdivided into a highstand systems tract （HST） and a transgressive systems tract （TST）.Reservoirs are principally developed in high-energy grain shoal deposits located in SQ2 and SQ3,with a minor occurrence in SQ1 and *** lithology of these shoal deposits is essentially composed of sandy dolomite and crystalline dolomite characterized by relatively low average porosity （2.61%） and permeability （1.0073 mD） *** increase of these values in several studied samples might be related to seepage and connecting dissolution pores and vugs through fractures which have a constructive effect on porosity and *** occurrence of karst caves through superimposed supergene karstification and bedding karstification highly improved the reservoir's physical properties in some *** reservoir space is dominated by intergranular dissolution pores,karst caves,and fractures,and their formation was controlled by sedimentation,diagenesis,penecontemporaneous dissolu
The recycling of CO2through electrochemical processes offers a promising solution for alleviating the greenhouse effect;however,the activation of CO2and desorption of*CO in electrocatalytic CO2reduction（ECR） frequen...
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The recycling of CO2through electrochemical processes offers a promising solution for alleviating the greenhouse effect;however,the activation of CO2and desorption of*CO in electrocatalytic CO2reduction（ECR） frequently encounter high energy barriers and competitive hydrogen evolution reactions（HERs）,which are urgent problems that need to be *** this study,a catalyst(P100-Fe-N/C) with homogeneous P-tuned FeN2binuclear sites（N2PFe-FePN2） was successfully synthesised,demonstrating satisfactory performance in the ECR to CO.P100-Fe-N/C attains a peak FECOof 98.01% and a normalized TOF of664.7 h-1at-0.7 VRHE,surpassing the performance of the Fe binuclear catalyst without P and singleatoms *** the MEA cell,a FECOexceeding 90% can still be *** functional theory analysis indicates that the asymmetric coordination configuration induced by the incorporation of P facilitates a reduction in the system's *** modulation of P results in the d-band centre of the catalyst being positioned closer to the Fermi level,which facilitates the interaction of the catalyst with CO2,allowing more electrons to be injected into the CO2molecule at the Fe binuclear sites and inhibiting the *** P-tuned FeN2binuclear sites effectively lower the*CO desorption barrier.
In this paper, the problem of cubature Kalman fusion filtering(CKFF) is addressed for multi-sensor systems under amplify-and-forward(AaF) relays. For the purpose of facilitating data transmission, AaF relays are utili...
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In this paper, the problem of cubature Kalman fusion filtering(CKFF) is addressed for multi-sensor systems under amplify-and-forward(AaF) relays. For the purpose of facilitating data transmission, AaF relays are utilized to regulate signal communication between sensors and filters. Here, the randomly varying channel parameters are represented by a set of stochastic variables whose occurring probabilities are permitted to exhibit bounded uncertainty. Employing the spherical-radial cubature principle, a local filter under AaF relays is initially constructed. This construction ensures and minimizes an upper bound of the filtering error covariance by designing an appropriate filter gain. Subsequently, the local filters are fused through the application of the covariance intersection fusion rule. Furthermore, the uniform boundedness of the filtering error covariance's upper bound is investigated through establishing certain sufficient conditions. The effectiveness of the proposed CKFF scheme is ultimately validated via a simulation experiment concentrating on a three-phase induction machine.
Nucleic acid analysis is a key technique that enables accurate detection of various *** nucleic acid testing typically requires access to specialized laboratories,equipment,and trained personnel,which hinders the wide...
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Nucleic acid analysis is a key technique that enables accurate detection of various *** nucleic acid testing typically requires access to specialized laboratories,equipment,and trained personnel,which hinders the widespread use of on-site testing for DNA and RNA ***,integrating gene editing technology with traditional nucleic acid detection methods,especially isothermal amplification technology,can help overcome the limitations associated with on-site *** combination can accomplish precise and swift detection of nucleic acid sequences,offering a robust tool for on-site *** Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated proteins(CRISPR/Cas)technology,which comprises the CRISPR system and Cas effector proteins,is a powerful tool that is advancing the field of nucleic acid ***,Cas12,Cas13,and Cas14 proteins have emerged as straightforward,effective,precise,sensitive,and cost-effective methods for in vitro nucleic acid detection because of their“collateral cleavage”*** combined with the“collateral cleavage”ability of Cas protein and isothermal amplification,CRISPR/Cas systems have great potential to advance nucleic acid *** article summarizes the research progress of different CRISPR/Cas systems and their applications in nucleic acid detection and future perspectives.
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