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The Supercritical Carbon Dioxide (S-CO _2 ) cOoled Lithium-Lead (COOL) blanket is under development for Chinese Fusion Engineering and Test Reactor. The thermal hydraulic assessment plays an important role for the comprehensive performance evaluation on the fusion blanket among the multi-physics fields. As the fusion reactor will enter into the engineering construction stage, it is important to study the thermal hydraulics performance on basis of the full model. Because it can accurately check the heat removal capability and thermoelectricity conversion efficiency, as well as provide essential input for the other physical fields. In this demand-driven, the analyses and optimization on the cooling system are put into priority on basis of the full banana model, including the manifold design and inlet/outlet pipes locations. Finally, the coolant pressure drop is highly reduced and the mass flow distribution becomes much more uniformly. For the S-CO _2 , 82.3% of the total mass flow rate is distributed into the key component first wall, and this is beneficial to face the high radiation heat flux. Besides, under different level of heat flux, the required total mass flow rate and pressure drop are obtained on premise that the coolant has enough ability to safely remove the heat away. For the Lead–Lithium (PbLi), the distribution of mass flow rate is designed as ‘ladder’ shape to adapt the unevenly spatial distributed nuclear heat along the radial direction, and the ratio is 8:2:1. Furthermore, the first law of thermodynamics is adopted for the trade-off analysis, which converts the total pressure drop of the two coolants into the pumping power, and it occupies only 1.3% of the total thermal power. This provides accurate and valuable data for the primary and secondary loop design, as well as the economic assessment on the fusion reactor. Finally, the Two Dimensional thermal hydraulic model containing the detailed layouts of different materials is used to study the coupling heat transfer effects between PbLi and S-CO _2 , as well as the MagnetoHydroDynamics (MHD) effects. The boundary conditions are derived from the results of full banana model, and the results show that the temperature of all materials is not exceeding the upper limits.

EX Lup is a low-mass pre-main-sequence star that occasionally shows accretion-related outbursts. Here, we present JWST/MIRI medium-resolution spectroscopy obtained for EX Lup 14 yr after its powerful outburst. EX Lup is now in quiescence and displays a Class II spectrum. We detect a forest of emission lines from molecules previously identified in infrared spectra of classical T Tauri disks: H _2 O, OH, H _2 , HCN, C _2 H _2 , and CO _2 . The detection of organic molecules demonstrates that they are back after disappearing during the large outburst. Spectral lines from water and OH are for the first time deblended and will provide a much-improved characterization of their distribution and density in the inner disk. The spectrum also shows broad emission bands from warm, submicron-size amorphous silicate grains at 10 and 18 μ m. During the outburst, in 2008, crystalline forsterite grains were annealed in the inner disk within 1 au, but their spectral signatures in the 10 μ m silicate band later disappeared. With JWST we rediscovered these crystals via their 19.0, 20.0, and 23.5 μ m emission, the strength of which implies that the particles are at ∼3 au from the star. This suggests that crystalline grains formed in 2008 were transported outwards and now approach the water snowline, where they may be incorporated into planetesimals. Containing several key tracers of planetesimal and planet formation, EX Lup is an ideal laboratory to study the effects of variable luminosity on the planet-forming material and may provide an explanation for the observed high crystalline fraction in solar system comets.

There is an urgent need for novel processes that can integrate different functional nanostructures onto specific substrates, so as to meet the fast-growing need for broad applications in nanoelectronics, nanophotonics, and flexible optoelectronics. Existing direct-lithography methods are difficult to use on flexible, nonplanar, and biocompatible surfaces. Therefore, this fabrication is usually accomplished by nanotransfer printing. However, large-scale integration of multiscale nanostructures with unconventional substrates remains challenging because fabrication yields and quality are often limited by the resolution, uniformity, adhesivity, and integrity of the nanostructures formed by direct transfer. Here, we proposed a resist-based transfer strategy enabled by near-zero adhesion, which was achieved by molecular modification to attain a critical surface energy interval. This approach enabled the intact transfer of wafer-scale, ultrathin-resist nanofilms onto arbitrary substrates with mitigated cracking and wrinkling, thereby facilitating the in situ fabrication of nanostructures for functional devices. Applying this approach, fabrication of three-dimensional-stacked multilayer structures with enhanced functionalities, nanoplasmonic structures with ∼10 nm resolution, and MoS _2 -based devices with excellent performance was demonstrated on specific substrates. These results collectively demonstrated the high stability, reliability, and throughput of our strategy for optical and electronic device applications.

In this work we study the effect of density-dependent gauge field on the collective dynamics of a harmonically trapped Bose–Einstein condensate (BEC), beyond the linear response regime. The density-dependent gauge field, as a backaction of the condensate, can in turn affect the condensate dynamics, resulting in highly nonlinear equations of motion. The dipole and breathing oscillations of the condensate along the direction of gauge field are coupled by this field. We find that, in the presence of this coupling, the collective motion of a quasi-one-dimensional condensate is still regular, i.e., periodic or quasiperiodic. In contrast, for a quasi-two-dimensional condensate, the collective dynamics of the condensate can become chaotic, when the density-dependent gauge field is strong. The mechanism is that the gauge field can also induce a Hall effect, manifested as an additional coupling between dipole and breathing oscillations in perpendicular direction, and chaotic motion is resulted from the interplay between these oscillations. Our findings reveal an important effect of dynamical gauge field on the nonlinear dynamics of a BEC.

In this study, one novel perfluoroalkyl silane with tetrafluoro- λ ^6 -sulfanyl bridging group named 4-(Tridecafluorohexyl sulfur tetrafluoride) Phenylethyl trichlorosilane (PFSTS) was successfully synthesized via fluorination and hydrosilylation. The structure was characterized by FT-IR and NMR Then, the product and the control subject 1H,1H,2H,2H-perfluorooctyltrichlorosilane (PFOTS) were finished onto PET fabrics through the method of dip-and-pad. The wettabilities of the treated PET fabrics were characterized by Water Contact Angles (WCA) and surface free energies measurements. X-ray Photo electron Spectroscopy (XPS) was used to validate the attachment, together with the chemical composition of the polymers on the surface of treated PET fabrics. The WCAs of PFOTS@PET and PFSTS@PET were 142.2°, 137.3°, while the WCA of untreated PET fabrics is 120° in general, indicating that PFTOS and PFSTS can provide good hydrophobicity by finishing PET fabrics. After the 48 h exposure to accelerated agingUV irradiation, sample of PFSTS@PET show a decreased CA value by 12.5% from 137.3° to 120.1°, while for sample of PFOTS@PET, the percentage of reductionis only 2.8%. It was found that the perfluoroalkyl trichlorosilane that containing –SF _4 – bridged group exhibited excellent water-repellency properties and had higher potential to UV degrade as possessing weak bond energy of C–S bond, so the PFSTS might act as an eco-friendly alternative to carbon-chain perfluoroalkyl derivatives in water-repellency areas.

Drug delivery is essential for effective therapy. Implantable controlled drug delivery systems (ICDDS) have become a research focus due to the associated advantages of continuous, long-duration, sustained delivery and the reduced side effects associated with this form of drug release. ICDDS can be designed to release drugs in accordance with different demands. Zero-order drug release, which involves a theoretically linear relationship between the cumulative amount of released drug and the amount of time taken for the release, is an important drug release rule for the control of chronic diseases. However, the release process is influenced by various parameters and zero-order drug release is therefore difficult to achieve. In this study, to achieve zero-order drug release, an implantable controlled drug delivery system with micro-hole (ICDDSM) was designed and fabricated with degradable polymer. Based on micro electromechanical systems (MEMS) technology, ICDDSM matrixes with circular and honeycomb structures were fabricated using the hot-press shaping method at a temperature of 75 °C, 30 N of force which were maintained for 150 s. A micro-hole with a diameter 100 μ m was formed using a femto-second laser. 5-fluorouracil was loaded into the ICDDSM and in-vitro experiments were conducted in 37 °C normal saline solution. The experimental results showed that the 20 mg of loaded 5-fluorouracil was released in 720 h with the relationship between the cumulative amount of released drug and the drug release time tending predominantly toward linearity. Zero-order drug release was thus achieved. This study proposed a new degradable ICDDS structure to achieve zero-order drug release, and the hot-press shaping process proved feasible for the efficient fabrication of the lower-cost polymer structure.

Multipole interferences have attracted a lot of interests in last decade due to extraordinary performance on beam control and scattering shaping. However, most of previous works focused on the dipole-based interferences while the quadrupole modes and other high-order multipole modes with unique properties were of less attention. In this work, we aim to expand the present dipole-based multipole-interference regime to the quadrupole-interference regime. We study the interference between an electric quadrupole (EQ) and a magnetic quadrupole (MQ) in both isolated and periodically arranged homogeneous cross dielectric structure. Through structural parametric control, the EQ and MQ can be precisely tuned to share the same resonant intensity at a specific wavelength, resulting in a generalized Kerker effect. Moreover, a dark MQ mode, which is orthogonal with the original MQ mode, arises when we increase the interaction between structure. We find that the spectral approaching between dark MQ and original bright EQ results in an EIT effect and Fano-shaped spectral reflection response. The induced Fano spectrum possesses tunable quality factors varying from ∼10 to >10 ^5 with the variation of EQ–MQ coupling efficiency. The numerically derived maximum quality factor (238, 618) of the dielectric EQ–MQ coupling system even exceeds the quality factors of many plasmonic resonant systems. We also prove that such spectrum can be adopted to refractive index sensing. Besides, we show that EQ–MQ coupling can bring about rapid 2 π phase change, which can be applied in metasurface designs. These results and conclusions about the EQ–MQ interference systems can provide a promising avenue for advanced optical devices.

The directionality of the response of gross primary productivity (GPP) to climate has been shown to vary across the globe. This effect has been hypothesized to be the result of the interaction between multiple bioclimatic factors, including environmental energy (i.e. temperature and radiation) and water availability. This is due to the tight coupling between water and carbon cycling in plants and the fact that temperature often drives plant water demand. Using GPP data extracted from 188 sites of FLUXNET2015 and observation-driven terrestrial biosphere models (TBMs), we disentangled the confounding effects of temperature, precipitation and carbon dioxide on GPP, and examined their long-term effects on productivity across the globe. Based on the FLUXNET2015 data, we observed a decline in the positive effect of temperature on GPP, while the positive effects of precipitation and CO _2 were becoming stronger during 2000–2014. Using data derived from TBMs between 1980 and 2010 we found similar effects globally. The modeled data allowed us to investigate these effects more thoroughly over space and time. In arid regions, the modeled response to precipitation increased since 1950, approximately 30 years earlier than in humid regions. We further observed the negative effects of summer temperature on GPP in arid regions, suggesting greater aridity stress on productivity under global warming. Our results imply that aridity stress, triggered by rising temperatures, has reduced the positive influence of temperature on GPP, while increased precipitation and elevated CO _2 may alleviate negative aridity impacts.

The number of dams globally has increased dramatically over the past few decades, providing reliable water resources by regulating natural streamflow. However, assessing the impact of dams on natural streamflow at a large scale remains a challenge due to lack of dam storage variation data. Here we analyzed flow regulation by dams from 1985 to 2014 over 153 basins globally using satellite remote sensing data. Two-thirds of global basins are regulated below 10%, and the high degree of regulation is mainly distributed in underdeveloped regions such as Central Asia and East Asia. Only 27% of basins have an increasing regulation trend from 1985 to 2014 and no basins show a decreasing trend. The gross domestic production, climatic water deficit and runoff show significant correlations with the flow regulation. We provide a global scale assessment of flow regulation by dams to support global water resources management.

Flash droughts, as sub-seasonal phenomena, are characterized by their rapid onset and significant impact on terrestrial ecosystems. However, understanding how vegetation responds to flash droughts and the mechanisms governing vegetation recovery remains elusive. Here, we analysed the response of vegetation productivity to flash droughts and identified the most relevant drivers controlling vegetation recovery using two soil moisture datasets (ERA5-land and Global Land Data Assimilation System) and two satellite-based vegetation productivity proxies (gross primary productivity, and solar-induced chlorophyll fluorescence). Our results show that South China and Northeast China stand out as hotspots for flash droughts, with higher frequency and speed. Notably, although the frequency of flash droughts in cropland is relatively low, and their speed is very high, with a median of 10.9% per pentad. Most ecosystems can recover to their normal state within 25 d. Vegetation with shallow roots, such as cropland and grassland, responds rapidly to flash droughts. Ecosystems generally exhibit extended response time with increasing plant rooting depth. The recovery rate of vegetation productivity from flash droughts is mainly controlled by vegetation physiology (decline rate of productivity upon exposure to flash drought) and modulated by flash drought characteristics, especially severity for forests and speed for cropland and grassland. This study provides valuable insights into the mechanisms underlying vegetation responses to flash droughts.

Flash drought events (FDEs) are projected to increase frequently in a warming world, significantly impacting ecosystem productivity and the global carbon cycle. The development of FDEs, induced by anomalies in different environmental variables, may cause different responses to the ecosystem’s gross primary productivity (GPP). However, the GPP variations and underlying mechanisms during the FDEs have rarely been quantified. This study collected long-term (>10 years) high-quality flux observations from the FLUXNET 2015 dataset to investigate GPP variations and their driving mechanisms during FDEs. Results showed that all vegetation types have two contrasting GPP variations during FDEs. One variation is a decreasing then increasing standardized GPP anomaly (V-shape response). The other shows an increase followed by decreasing standardized GPP anomaly (inverted V-shape response). The V-shape GPP response to FDEs was induced by increased soil water content deficit at the onset stage of FDEs. In contrast, the inverted V-shape GPP response to FDEs was induced by increased net radiation at the onset of FDEs. Such results indicated competing moisture supply and atmospheric moisture demand at the onset of FDEs, controlling the two contrasting ecosystem’s carbon responses with its development. Moreover, the contribution of water use efficiency to the magnitude of the V-shape GPP response (64.5 ± 22.4%) is greater than that to the inverted V-shape GPP response (47.6 ± 18.7%). This study identified the two contrasting types of GPP variations during FDEs and their driving mechanisms across multiple ecosystem types which can improve our ability to predict the future effects of more frequent FDEs on ecosystem productivity.

In an effort to develop computational tools for predicting radiation hazards from solar energetic particles (SEPs), we have created a data-driven physics-based particle transport model to calculate the injection, acceleration, and propagation of SEPs from coronal mass ejection (CME) shocks traversing through the solar corona and interplanetary magnetic fields. The model runs on an input of corona and heliospheric plasma and magnetic field configuration from a magnetohydrodynamic model driven by solar photospheric magnetic field measurements superposed with observed CME shocks determined from coronagraph images. SEP source particles are injected at the shock using the result of diffusive shock acceleration formulation from a characteristic obliquity-dependent injection from a heated solar wind thermal tail population. With several advanced computation techniques involving stochastic simulation and integration, the model obtains the particle intensity at any location in interplanetary space through the rigorous solution to the time-dependent 5D focus transport equation in the phase space that includes perpendicular diffusion. We apply the model to the 2011 November 3 CME event. The calculation results reproduce multispacecraft SEP observations at Earth and STEREO-B reasonably well without normalization of particle flux. The observations at STEREO-A can be reproduced by rescaling particle energy or modified energy dependence of particle diffusion coefficients. This circumsolar SEP event seen by spacecraft at Earth, STEREO-A, and STEREO-B at widely separated longitudes can be explained by diffusive shock acceleration by a single CME shock with a moderate speed.

This paper presents a stochastic three-dimensional focused transport simulation of solar energetic particles (SEPs) produced by a data-driven coronal mass ejection (CME) shock propagating through a data-driven model of coronal and heliospheric magnetic fields. The injection of SEPs at the CME shock is treated using diffusive shock acceleration of post-shock suprathermal solar wind ions. A time-backward stochastic simulation is employed to solve the transport equation to obtain the SEP time–intensity profile at any location, energy, and pitch angle. The model is applied to a SEP event on 2020 May 29, observed by STEREO-A close to ∼1 au and by Parker Solar Probe (PSP) when it was about 0.33 au away from the Sun. The SEP event was associated with a very slow CME with a plane-of-sky speed of 337 km s ^−1 at a height below 6 R _S as reported in the SOHO/LASCO CME catalog. We compute the time profiles of particle flux at PSP and STEREO-A locations, and estimate both the spectral index of the proton energy spectrum for energies between ∼2 and 16 MeV and the equivalent path length of the magnetic field lines experienced by the first arriving SEPs. We find that the simulation results are well correlated with observations. The SEP event could be explained by the acceleration of particles by a weak CME shock in the low solar corona that is not magnetically connected to the observers.

Composition-controllable ternary CdSexS1-x quantum dots (QDs) with multiple emission colors were obtained via a hot-injection-like method at a relatively low injection temperature (230°C) in octadecene. Then highly fluorescent CdSexS1-x=ZnS core/shell (CS) QDs were synthesized by a facile single-molecular precursor approach. The fluorescent quantum yield of the resulting green (λem D 523 nm), yellow (λem D 565 nm) and red (λem D 621 nm) emission of CS QDs in toluene reached up to 85%, 55% and 39%, respectively. Moreover, a QDs white light-emitting diode (QDs-WLED) was fabricated by hybridizing green-, yellowand red-emitting CdSexS1-x=ZnS CS QDs/epoxy composites on a blue InGaN chip. The resulting four-band RYGB QDs-WLED showed good performance with CIE-1931 coordinates of (0.4137, 0.3955), an Ra of 81, and a Tc of 3360 K at 30 mA, which indicated the combination of multiple-color QDs with high fluorescence QYs in LEDs as a promising approach to obtain warm WLEDs with good color rendering. [ABSTRACT FROM AUTHOR]

The oxidation behavior of Mn1.5CO1.5O4 (MCO)-coated Haynes 230 (H230) and Crofer 22 APU was investigated between 700 and 900°C. The oxidation kinetics of the coated alloys was compared with that of base alloys at 800°C. An apparent two-stage kinetics behavior of the MC0-coated Crofer 22 APU was observed. The coating effectively reduced the oxidation rate constants of Crofer 22 APU by 5.5 times, whereas it did not seem to affect the oxidation kinetics of H230. The oxidation activation energies of the coated alloys suggest distinctly different oxidation mechanisms between the coated H230 and Crofer 22 APU. A Cr-modified spinel was observed in the interface region between the metal oxide scale and the spinel coating after long-term oxidation for both alloys. A semiquantitative model of oxidation kinetics was developed to explain the different behaviors observed. Apparently, the Cr-modified spinel may play a more important role on H230 during long-term oxidation. The heat-treatment of H230 in the reducing environment used for the MCO coating application processes appeared to debit oxidation resistance of the base alloy. The optimization of the MCO application process is expected to benefit oxidation resistance as well as chromia containment on H230. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MCNTs) can be obtained by heating grass in the presence of a suitable amount of oxygen. Grass contains a large amount of vascular bundles in the stem and nervation. The major compositions of them are cellulose, hemicellulose and lignin. In the present approach, a rapid heat treatment (at about 600 °C) and the participation of oxygen make the vascular bundles become dehydrated and turn into carbon nanotubes. The diameters of the carbon nanotubes obtained are between 30 and 50 nm. [ABSTRACT FROM AUTHOR]

Electrical transport and low field magnetoresistance (MR) are reported in the La2/3Ca1/3Mn1-xO3 (x = 0–0.16) samples, which are prepared by the sol–gel method followed by a sintering treatment at 1100°C. Experimental results show, for x = 0.06, an MR platform is observed in a temperature ~200 K under the magnetic field of 0.5 T. With an increase in x, the MR effect gets augmented. For the sample with x = 0.16, its MR peak is as high as 50%. [ABSTRACT FROM AUTHOR]

Chip based bio/chemical analysis relies on networks of fluidic channels that are connected to reaction chambers and sensors. For sensitive detection it is important to scale down the size of the channels so that they approach the relevant length scales of the molecules of interest. Here we have made sealed channels on the 100 nm scale using nanoimprinting to pattern the sacrificial polymer polynorbornene over areas of several square centimetres. We have combined channels of different cross sections and we have shown that the nanochannels can be made hydrophilic with DNA transported electrophoretically in these self-sealed channels. [ABSTRACT FROM AUTHOR]

Economic development, resource scarcity and climate change pose enormous challenges to the food–energy–water (FEW) nexus, calling for integrative resources governance to improve the synergy between subsystems. However, it is unclear about the synergy evolution of the FEW nexus in temporal and spatial scales. This paper uses the network analysis to explore the FEW nexus in China’s Yangtze River Economic Belt. First, the comprehensive index system containing subsystems, order parameters and eigenvectors are determined in causal paths. Second, the synergetic network among order parameters is developed, and the centrality analysis is then conducted to identify the influencing factors. Third, the Bayesian network among eigenvectors is constructed to analyze the sensitivity of the dominant influencing factors. The results show that: (a) Energy subsystem has the highest centralities and dominates the FEW nexus. (b) From the perspective of time variability, the network centralization reaches the highest in 2007, but reaches the lowest in 2013, showing a downward trend, so we should adhere to the national strategy of synergetic development to realize the resource sustainability. (c) From the perspective of spatial sensitivity, upper reach (UR) is sensitive to food-related factors while lower reach (LR) is sensitive to energy-related factors. Therefore, the development of agriculture in upper UR should focus on protection, and the development of industry in LR should focus on remediation. The significance of the research is to construct a network analysis framework for better understanding the spatio-temporal variability of the FEW nexus in Yangtze River Economic Belt.

Despite numerous assessments of the impact of land-use change (LUC) on terrestrial evapotranspiration (ET) that have been conducted using land surface models (LSMs), no attempts have been made to evaluate their performance in this regard globally. Errors in simulating LUC impacts on ET largely stem from LUC data interpretation (LI, i.e. mapping of gridded LUC data into annual plant function types) and model structure (MS, i.e. parameterization of land-surface processes). The objective of this study was to benchmark ET estimates from four LSMs using the Zhang-curve, a prototype of the Budyko framework that has been validated against global hydrological observations and used widely to quantify the impacts of LUC on ET. A framework was further proposed to quantify and attribute errors in estimated ET changes induced by LI or MS. Results showed that all LSMs underestimated ET changes by about 55%–78%, and 37%–48% of the error was attributable to LI, but only 11%–32% of the error was attributable to MS across the four LSMs. From a hydrological perspective, our analysis provided insights about the errors in estimated impacts of LUC on ET by LSMs. The results demonstrated that LUC data interpretation accounted for a larger fraction of errors than LSM structure. Therefore, there is an urgent need for the defining and development of consistent protocols for interpreting global LUC data for future assessments.

Over recent decades, concern has grown regarding the effects of climate change and artificial river projects on the variability of river floods. Specifically, it has been demonstrated that the Mississippi River flood hazard has been amplified by river engineering. In contrast, the world’s largest reservoir group with the Three Gorges Reservoir at its core has been built along the upper reaches of the Yangtze River, but the question of whether there has been a positive effect on flood control is worthy of discussion. Here, we revisit nine paleofloods from the ancient stone inscriptions for the first time and show that while annual peak discharge in the upper reaches of the Yangtze River is dominated by sunspot numbers and the North Atlantic Oscillation, the magnitude of flooding has been decreased by the reservoir group, which diminished flood hazard through reversing or strengthening the direction of climate control on the flood.

Grain-growth behaviors of TC4–DT alloy in a narrow temperature range (990 °C−1050 °C) were systematically investigated, and the effects of which on the lamellar structural evolution and mechanical properties were quantitatively evaluated. Microstructural observations indicated that prior β grain size increased with an increase in heat-treatment temperature and time, which was described by the modified Sellars model. The grain-growth exponent ( n = 2.741) and activation energy ( Q = 161.0 kJ mol ^−1 ) during β treatment were confirmed. The α colony size similar to β grain varied significantly with the heat-treatment conditions, while α plate thickness changed slightly. The Hall–Petch equation could qualitatively exhibit the relationships between the lamellar microstructure parameters (prior β grain size, α colony size, and α plate thickness) and mechanical properties (strength, ductility, and impact toughness). The fine prior β grain that contained different orientated α colonies produced more boundaries to hinder dislocation motion and crack propagation, which contributed a more circuitous crack growth path. The results indicated that the control of α colony size was critical to improve the mechanical performance of TC4–DT alloy.

Due to the emergence of 5G technology and wide applications for the internet of things (IoT), metamaterials are expected to have stronger adaptability and higher performance. However, numerous previous metamaterials based on indium tin oxide (ITO) film fail to be electrically tunable and need external power. In this work, we propose an optically transparent and reconfigurable metasurface based on ITO film with varactor diodes. By varying the capacitances of varactors incorporated into the elements, the phase responses can be modulated as desired. In addition, based on these designed elements, we present four schemes to realize distinct scattering fields. In order to achieve an autonomous power supply for the metasurface, we integrate a solar cell by using the transparency of ITO. The simulated and measured results have good accordance, which demonstrates the excellent performance of the proposed metasurface. This work facilitates the flexibility of metasurfaces and paves the way for applications in outside communications. [ABSTRACT FROM AUTHOR]

The biphase magnetic heterostructure (Ni/Fe20Ni45Co25Si2B8/micro-planarcoil/Fe20Ni45Co25Si2B8/micro-planar coil/Fe20Ni45Co25Si2B8/Ni) bonded with a pair of thin magnets shows an improved asymmetric and hysteretic giant magnetoimpedance (GMI) effect with respect to an external dc magnetic field. This is attributed to the modification of the soft amorphous magnetic alloy’s (Fe20Ni45Co25Si2B8) permeability by the hysteretic magnetostrictive stress from the neighboring magnetostrictive Ni layer besides the magnetostatic coupling. More importantly, nonvolatile logic gates, such as NOR and NAND, can be implemented with either a single GMI laminate or arrays. On one hand, after applying two sequential magnetic field pulses as the logic inputs to a single proposed laminate, the nonvolatile output voltages are positive high (logic 1) or positive low (logic 0) depending on the signs and magnitudes of pulses. On the other hand, after applying the magnetic field pulses parallel to the GMI laminates arrays, different logic functions can be programmed and realized at run-time. The integration of memory and logic functions enables the proposed GMI laminate to be a possible candidate for future computing systems beyond von Neumann architecture. [ABSTRACT FROM AUTHOR]

In this paper, we propose a synchrophasor estimator which can meet the M and P class requirements of the IEEE standard C37.118.1 simultaneously. Meanwhile, the phase error of the estimator is always smaller than 0.05 degrees, which makes it applicable in distribution networks. The errors of the interpolated dynamic discrete Fourier transform (IpD2FT) due to interharmonic interferences are investigated. Then the optimal frequencies where the IpD2FT has the smallest interharmonic interference are obtained. To achieve higher accuracy, the Taylor–Fourier multifrequency (TFM) model-based method is used to estimate and then eliminate the interharmonic component further. Concerning response time requirements, robust thresholds for transient detection are obtained based on numerous simulations, and the Kaiser-based IpD2FT is used to meet the corresponding limits. Canonical tests stated in the IEEE standard C37.118.1 and specific tests which could occur in distribution networks are both carried out to verify the performance of the proposed method. [ABSTRACT FROM AUTHOR]

The Fe3O4@Au core–shell nanocomposites, as the multifunctional magnetic surface enhanced Raman scattering (SERS) substrates, were fabricated successfully by the seeds growth method based on the Fe3O4–Au core-satellite nanocomposites. The SERS properties of the Fe3O4–Au core-satellite nanocomposites and the Fe3O4@Au core–shell nanocomposites were compared using 4-aminothiophenol (4-ATP) as the probe molecule. It was found that Fe3O4@Au core–shell nanocomposites showed better SERS performance than Fe3O4–Au core-satellite nanocomposites. The Au shell provided an effectively large surface area for forming sufficient plasmonic hot spots and capturing target molecules. The integration of magnetic core and plasmonic Au nanocrystals endowed the Fe3O4@Au core–shell nanocomposites with highly efficient magnetic separation and enrichment ability and abundant interparticle hot spots. The Fe3O4@Au core–shell nanocomposites could be easily recycled because of the intrinsic magnetism of the Fe3O4 cores and had good reproducibility of the SERS signals. For practical application, the Fe3O4@Au core–shell nanocomposites were also used to detect thiram. There was a good linear relationship between the SERS signal intensity and the concentration of thiram from 1 × 10−3 to 1 × 10−8 M and the limit of detection was 7.69 × 10−9 M. Moreover, residual thiram on apple peel was extracted and detected with a recovery rate range of 99.3%. The resulting substrate with high SERS activity, stability and strong magnetic responsivity makes the Fe3O4@Au core–shell nanocomposites a perfect choice for practical SERS detection applications. [ABSTRACT FROM AUTHOR]

We present ALMA observations of 12CO, 13CO, and C18O J = 2–1 lines and the 230 GHz continuum for the FU Ori–type object (FUor) V900 Mon (d ∼ 1.5 kpc), for which the accretion burst was triggered between 1953 and 2009. We identified CO emission associated with a molecular bipolar outflow extending up to an ∼104 au scale and a rotating molecular envelope extending over >104 au. The interaction with the hot energetic FUor wind, which was observed using optical spectroscopy, appears limited to a region within ∼400 au of the star. The envelope mass and collimation of the extended CO outflow suggest that the progenitor of this FUor is a low-mass Class I young stellar object (YSO). These parameters for V900 Mon, another FUor, and a few FUor-like stars are consistent with the idea that FUor outbursts are associated with normal YSOs. The continuum emission is marginally resolved in our observations with a 0.″2 × 0.″15 (∼300 × 225 au) beam, and a Gaussian model provides a deconvolved FWHM of ∼90 au. The emission is presumably associated with a dusty circumstellar disk, plus a possible contribution from a wind or wind cavity close to the star. The warm compact nature of the disk continuum emission could be explained with viscous heating of the disk, while gravitational fragmentation in the outer disk and/or a combination of grain growth and their inward drift may also contribute to its compact nature. [ABSTRACT FROM AUTHOR]