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We present COSBO-7, a strong millimeter source known for more than 16 yr that just revealed its near-to-mid-IR counterpart with the James Webb Space Telescope (JWST). The precise pinpointing by the Atacama Large Millimeter/submillimeter Array on the exquisite NIRCam and MIRI images show that it is a background source gravitationally lensed by a single foreground galaxy, and the analysis of its spectral energy distribution by different tools is in favor of photometric redshift at z _ph > 7. Strikingly, our lens modeling based on the JWST data shows that it has a regular disk morphology in the source plane. The dusty region giving rise to the far-IR-to-millimeter emission seems to be confined to a limited region to one side of the disk and has a high dust temperature of >90 K. The galaxy is experiencing starburst both within and outside of this dusty region. After taking the lensing magnification of μ ≈ 2.5–3.6 into account, the intrinsic star formation rate is several hundred M _⊙ yr ^−1 both within the dusty region and across the more extended stellar disk, and the latter already has >10 ^10 M _⊙ of stars in place. If it is indeed at z > 7, COSBO-7 presents an extraordinary case that is against the common wisdom about galaxy formation in the early Universe; simply put, its existence poses a critical question to be answered: how could a massive disk galaxy come into being so early in the Universe and sustain its regular morphology in the middle of an enormous starburst?

We study the spectral and temporal properties of the black hole (BH) X-ray transient binary SLX 1746–331 during the 2023 outburst with NICER, NuSTAR, and Insight-HXMT observations. Through the joint fitting of the spectra from NICER, NuSTAR, and Insight-HXMT, the spin and inclination angles are measured for the first time as 0.85 ± 0.03 and 53° ± 0.°5, respectively. Accordingly, the mass of the compact star is updated from the previous lower limit of 3.3 ± 2.1 M _⊙ to 5.5 ± 3.6 M _⊙ , which is consistent with 5.2 ± 4.5 M _⊙ measured with an empirical mass–luminosity correlation of BH samples. With more NICER observations covering the later decay of the outburst, we confirm that the entire outburst was dominated by the disk emissions, and the thermal spectrum follows $F\propto {T}_{\mathrm{in}}^{3.974\pm 0.003}$ , until a luminosity of over 2 magnitudes lower than the maximum of the outburst.

We propose a method based on the Hilbert–Huang transform (HHT) to recover the high-energy waveform of low-frequency quasiperiodic oscillations (QPOs). Based on the method, we successfully obtain the modulation of the phase-folded light curve above 170 keV using the QPO phase reconstructed at lower energies in MAXI J1535–571 with Insight-HXMT observations. A comprehensive simulation study is conducted to demonstrate that such modulation indeed originates from the QPO. Thus, the highest energies turn out to significantly exceed the upper limit of ∼100 keV for QPOs reported previously using the Fourier method, marking the first opportunity to study QPO properties above 100 keV in this source. Detailed analyses of these high-energy QPO profiles reveal different QPO properties between the 30–100 and 100–200 keV energy ranges: the phase lag remains relatively stable, and the amplitude slightly increases below ∼100 keV, whereas above this threshold, soft phase lags and a decrease in amplitude are observed. Given the reports of a hard-tail detection in broad spectroscopy, we propose that the newly discovered QPO properties above 100 keV are dominated by the hard-tail component, possibly stemming from a relativistic jet. Our findings also indicate a strong correlation between the QPOs originating from the jet and corona, supporting the scenario of jet–corona coupling precession. We emphasize that our proposed HHT-based method can serve as an efficient manner in expanding the high-energy band for studying QPOs, thereby enhancing our understanding of their origin.

Swift J1727.8–1613 is a black hole X-ray binary newly discovered in 2023. We perform spectral analysis with simultaneous Insight-HXMT, NICER, and NuSTAR observations when the source was approaching the hard intermediate state. Such a joint view reveals an additional hard component apart from the normally observed hard component with reflection in the spectrum, to be distinguished from the usual black hole X-ray binary systems. By including this extra component in the spectrum, we have measured a high spin of ${0.98}_{-0.07}^{+0.02}$ and an inclination of around ${40}_{-0.8}^{+1.2}$ °, which is consistent with NICER results reported before. However, we find that the additional spectral component cannot be exclusively determined due to the model degeneracy. Accordingly, a possible jet/corona configuration is adjusted to account for the spectral fitting with different model trials. The extra component may originate either from a relativistic jet or a jet base/corona underneath a slow jet.

The northwestern Pacific monsoon trough (NWPMT) deeply impacts socio-economic development and human security over East Asia by supplying moisture to the summer monsoon rainfall and modulating tropical cyclone activities. However, considerable inter-model spreads in the coupled model inter-comparison project phase 6 models make the future projection of the NWPMT less reliable. Here, we find that the inter-model spread of the NWPMT change is significantly correlated with the central equatorial Pacific sea surface temperature change, and mainly determined by the equatorial thermocline sharpness in the historical simulations. According to the emergent constraint method, the central equatorial Pacific SST would warm up about 6% slower than the multi-model mean with 56% uncertainty reduced. Correspondingly, the NWPMT would slacken westward with 36% uncertainty reduced. Results here emphasize the importance of examining and reducing systematic model biases in simulating thermocline sharpness that have been overlooked in past literatures, before achieving more reliable future projections.

Mold on the phosphogypsum wallboard seriously hinders the resource utilization of phosphogypsum, and incorporating inorganic antibacterial materials can effectively inhibit mold growth. In this study, Escherichia coli and wallboard mold were used as experimental strains, and the antibacterial activity of antibacterial material-modified calcined gypsum from phosphogypsum (CPG) was determined using the inhibition zone method and mold surface growth area analysis. Characterization techniques such as XRF, XRD, and SEM were used to study the phase composition and microstructure of the samples, and an antibacterial model was constructed to explore the antibacterial mechanism. The results indicated that using E. coli as an indicator bacterium, ZnO-0.05TiO _2 -CPG exhibited the best bactericidal effect, while ZnO-CPG exhibited the best bacteriostatic effect. Against mold, ZnO contents of 2.5% or 5% demonstrated strong antibacterial properties, with compressive strengths of 10.1 MPa and 9.95 MPa, respectively, meeting the requirements of ≥3.50 MPa for compressive strength according to the ‘Lightweight Partition Plates for Building’ standard (GB/T 23451 2009). The superior antibacterial performance of ZnO compared to TiO _2 is attributed to the slow release of Zn ^2+ , which disrupts cell membranes and the generated reactive oxygen species inhibit cell growth.

Molecular dynamics and mass transportation in porous structures provide a basis for us to understand catalysis, energy storage and generation, and biological processes in porous confinements. While conventional methods extract macroscopic information in an ensemble-averaged manner, we intend to follow the journey of individual particles and molecules in porous structures relevant to cigarette filters by tracking the single-object dynamics in real space and real time. Nanoparticles of various sizes are embedded in fibrous frameworks of agarose where small particles (50 nm) can explore pores and their connections, locally mapping out the porous structure, middle-sized particles (100 nm) are trapped in single pores to fluctuate within, and large particles (500 nm) are fully immobilized by surrounding fibers. This model system is relevant to the retention and filtration of tar particles or other kinds of particulate matters by fibrous cellulose frequently used in cigarette filters. A molecular tracer is loaded to zeolite-based porous structures, where the majority are fixated in space by adsorption or micropore trapping, exhibiting localized trajectories within a 10-nm radius, and the minority are mobile to scout macropores. This molecular system may elucidate on how aromatic molecules like PAHs are adsorbed and transported in a matrix of mixed micro-, meso-, and macropores.

V-N microalloying treatment is an important way to improve the service performance of non-quenched and tempered ship plate steel. Herein, the influence of V(C, N) on the evolution of microstructure and improvement of mechanical properties was studied. In addition, the relationship between microstructure and mechanical properties of V-N microalloyed high strength ship plate steel was revealed. The results showed that the composite addition of V and N not only formed a fine dispersed precipitated phase, but more importantly, significantly refined the ferrite/pearlite microstructure, promoted the formation of intragranular acicular ferrite, increased the proportion of high angle grain boundaries, and decreased the kernel average misorientation value. The optimization of microstructure brought about by V-N microalloying achieved synchronous improvement of strength and cryogenic toughness. The impact energy of V-N microalloying ship plate steel increased from 97 J of V-N-free ship plate steel to 239 J at −40 °C, and the impact fracture mode changed from brittle quasi-cleavage fracture to microvoid coalescence fracture with a large number of equiaxial dimples.

Magnetic braking (MB) plays an important role in the evolution of close low-mass X-ray binaries (LMXBs). It is also essential to the formation of ultracompact X-ray binaries (UCXBs). There have been lively investigations on the MB mechanism(s) in both single stars and close binaries including cataclysmic variables and neutron star (NS) LMXBs but with diverse conclusions. In this paper we explore the effect of MB on the black hole (BH) LMXB evolution. We combine binary population synthesis with detailed binary evolution to obtain the expected properties of the Galactic BH LMXB population. The simulated results are compared with the observational data including the BH mass, companion mass, companion temperature, orbital period, and mean accretion rate. Our results reveal that the MB laws with relatively low efficiency (i.e., RM12 and RVJ83) exhibit better agreement with observations, contrary to what was found for NS LMXBs. This raises the interesting question about whether MB really follows the same unified law in different types of binaries. We also predict that only a very small fraction (≲2.5%) of BH LMXBs can evolve to be UCXBs. This explains why no BH UCXB has been discovered so far.

During January–May 2023, an extreme prolonged drought dominates Southwest China, which caused a severely damage of local water availability, power supply and productivity in Yunnan Province. It is noted that the initiation and maintenance of this extreme drought was concurrent with phase transition from La Niña into El Niño. We demonstrate that this severe drought event was partly attributed to the relay influences of La Niña and El Niño evolution. The anomalous enhanced cyclone over the western North Pacific (WNP) associated with mature La Niña triggered anomalous downwards motion and reduced moisture supply to Southwest China, contributing to drought initiation. As the La Niña decay, the anomalous WNP cyclone gradually weakened in late winter and early spring. Moreover, the eastwards shifting of anomalous WNP cyclone intensified by the El Niño developing and maintained anomalous northerlies in this region. The preceding winter La Niña favored the prolonged MJO activities over the tropical western Pacific in late spring, which re-intensified anomalous WNP cyclone and aggravated drought in Yunnan. The local extreme droughts are a footprint over Southeast Asia, showing a few months predictability as a possible response to the transition from the phase of La Niña to El Niño. This is supported by the similar extreme droughts in history during phase transition from La Niña into El Niño.

Empowering industrial green development with the digital economy represents a crucial approach to advancing the green transformation of China’s economy and achieving high-quality economic development. Based on panel data from 279 cities in China from 2011 to 2021, this article uses the spatial econometrics model and threshold effect model to explore the spatial effect and nonlinearity of digital economy (DE) on industrial green development (IGD). The results show that, both DE and IGD exhibit fluctuating upward trends in China. There exists stronger spatial linkage effect in the eastern coastal areas, but this effect is weaker in the central and western regions. Furthermore, DE has significantly promoted IGD, and the conclusion remains robust after a series of endogeneity and robustness tests. Additionally, the promotion of the DE for IGD is characterized by regional spillovers and non-linear dynamics. The research results can serve as a theoretical support and decision-making basis for China to enhance industrial green development, promote the construction of an ecological civilization, and implement sustainable development strategies.

Galaxy pairs hold significant importance in understanding the evolution of galaxies, and the extensive search for a large sample of galaxy pairs is meaningful. In this article, we develop a deep learning-based approach for the search of galaxy pairs and conduct a comprehensive search on Sloan Digital Sky Survey (SDSS) images. In nine million photometric images, 17,965 physical galaxy pairs with spectral or photometric redshifts are detected. Four sets of results are provided, including physical pairs determined by two spectral redshifts, two photometric redshifts, one spectral redshift, and one photometric redshift, and visual irregular pairs that have no precise redshift information but can be inferred as physical galaxy pairs based on the morphological changes. Then their morphological and physical characteristics are explored, the redshifts of most targets are around 0.1, and as the redshift difference between two galaxies increases, the number of galaxy pairs gradually reduces. The distributions of star formation rate (SFR) are not the same for different morphologies of galaxy pairs, irregular pairs have higher SFR than the other three types, and statistics indicate that the SFR of galaxies depends on both nearby galaxies and internal properties. Color and stellar mass are also key properties of galaxies which can reflect the status of galaxy pairs. Compared to other surveys, a greater number of galaxy pair targets are detected, and this is also the first extensive detection of galaxy pairs in SDSS images using photometric redshifts. These galaxy pair samples can greatly aid in the study of galaxy evolution.

Photonic spin Hall effect (PSHE) in chiral PT-symmetric systems exhibits many exotic features, but the underlying physical mechanism has not been well elucidated. Here, through rigorous calculations based on full-wave theory, we reveal the physical mechanism of the exotic PSHE and identify a chirality-enabled topological phase transition. When circularly polarized light is incident on a chiral PT-symmetric system, the transmitted beam contains two components: a spin-flipped abnormal mode that acquires a geometric phase (exhibiting a vortex or a spin-Hall shift), and a spin-maintained normal mode that does not exhibit such a phase. If the phase difference between the cross-polarized Fresnel coefficients cannot be ignored, it results in a chirality-enabled phase and intensity distribution in the abnormal mode, which induces an exotic PSHE. Consequently, as the incident angle increases, a chirality-induced topological phase transition occurs, namely the transition from the vortex generation to the exotic PSHE. Finally, we confirm that the asymmetric and periodic PSHE in the chiral slab is also related to the phase difference between the cross-polarized Fresnel coefficients. These concepts and findings also provide an opportunity for unifying the phenomena of topological phase transitions in various spin-orbit photonic systems.

Large samples of Am and Ap stars are helpful in studying the interplay between phenomena like atomic diffusion, magnetic fields, and stellar rotation in stellar astrophysics. Existing samples of Am and Ap stars, mostly obtained from spectral data with a signal-to-noise ratio in the g band (S/Ng) greater than 50, can benefit from expansion by exploring spectra with lower S/Ng. Therefore, this paper proposes an ensemble regression model applicable to spectra with a minimum S/Ng of 30. Using the model, we identify 21,361 Am candidates, of which 11,614 are new, and 6182 Ap candidates, of which 4978 are new, from LAMOST DR10. The Am sample size has increased by 60% and the Ap sample size has increased by 180% compared to the previous sample. In terms of effective temperature ( T _eff ), the Am candidates range mainly from 6000 to 8500 K, while the Ap candidates range from 6000 to 11,700 K. The surface gravity ( $\mathrm{log}g$ ) distributions for Am and Ap candidates differ in the range of 3.25–4.75 dex. The number of Am candidates increases stepwise, in contrast to the relatively uniform distribution of Ap candidates across the entire surface gravity range. Regarding metallicity ([Fe/H]), Am candidates typically range from −0.75 to 0.38 dex, peaking near 0 dex, while Ap candidates are distributed from −1.38 to 0.38 dex, with a peak near −0.5 dex.

Islet transplantation is a promising strategy for diabetes mellitus treatment as it can recapitulate endogenous insulin secretion and provide long-term glycemic control. Islet models constructed in biomaterial scaffolds that reproduce biological characteristics of native islets is a feasible option to circumvent the dilemma of donor shortage and the requirement of chronic immunosuppression. Herein, we developed bioinspired artificial microcapsule-based islet models with microvessels for glycemic control using microfluidic electrospray strategy. Microfluidic electrospray can generate uniform hydrogel microcapsules with core-shell structure for encapsulating islet cells. The cell-laden microcapsules enabled the efficient transportation of nutrient, oxygen, and insulin; as well as the incorporation with microvessels for prompting glucose responsiveness and molecular exchange. We demonstrated by in vivo experiments that the blood glucose, food intake, and body weight of diabetic mouse models were alleviated, and the glucose tolerance was promoted after the engraftment of islet microcapsules. We further demonstrated the improved functionality of transplanted islet model in insulin secretion, immune escape, and microcirculation using standard histological and molecular analysis. These results indicated that the microcapsules with microvessels are promising artificial islet models and are valuable for treating diabetes.

The High Altitude Detection of Astronomical Radiation (HADAR) is a novel wide-field Cherenkov Telescope. It is designed for gamma-ray astronomy in the energy range of 10 GeV to 100 TeV, with gamma-ray bursts (GRBs) being one of its primary research focuses. To assess its complementary capabilities, this study first presents the Crab sensitivity of HADAR. Then, to compare the sensitivity of GRBs, the observation time for all experiments is standardized to 100 s. To clearly demonstrate HADAR’s advantages, we estimate its observational results with a 221009A-like GRB. The study found that HADAR is capable of more comprehensively recording the bending and absorption of self-Compton radiation, which is expected to fill observational gaps in space- and ground-based experiments. We anticipate that this facility will ensure a large statistical GRB sample and advance our understanding of GRBs.

The wavelengths and transition rates of W ^40+ -W ^42+ ions within the range of 40–140 Å, have been calculated using the Flexible Atomic Code of the Dirac-Fock-Slater method with a central potential. We investigated the charge state distribution of W ^38+ -W ^45+ ions at different temperatures by constructing an appropriate rate equation and demonstrate the importance of the dielectronic recombination process. Additionally, we simulated the emission spectra of W ^40+ -W ^42+ ions in a Tokamak plasma environment using collisional-radiative modeling. Our findings demonstrate strong agreement with experimental results and other related theoretical investigations. Finally, we propose certain pairs of transition lines as diagnostic tools for plasma temperature and density, leveraging the correlation between line intensity ratio and electron temperature and density.

We study the radial evolution of the inertial-range solar wind plasma turbulence and its anisotropy in the outer heliosphere. We use magnetic field ( B ) measurements from the Voyager 2 spacecraft for heliocentric distances R from 1 to 33 au. We find that the perpendicular and trace power spectral densities (PSDs) of the magnetic field ( ${E}_{{{\rm{B}}}_{\perp }}$ and ${E}_{{{\rm{B}}}_{\mathrm{Tr}}}$ ) still follow a Kolmogorov-like spectrum until 33 au. The parallel magnetic field PSD, ${E}_{{B}_{\parallel }}$ , transits from a power-law index of −2 to −5/3 as the distance crosses R ∼ 10 au. The PSD at frequencies 0.01 Hz < f < 0.2 Hz flattens at R > 20 au, gradually approaching an f ^−1 spectrum, probably due to instrument noise. At 0.002 Hz < f < 0.1 Hz, quasi-parallel propagation dominates at 1 au < R < 7 au, with quasi-perpendicular propagation gradually emerging at R > 5 au. For R > 7 au, oblique propagation becomes the primary mode of propagation. At smaller frequencies of f < 0.01 Hz, ${E}_{{{\rm{B}}}_{\perp }}$ increases with propagation angle at 1 au < R < 5 au, and in contrast decreases with propagation angle at R > 5 au due to the enhanced power level at propagation angles smaller than 20°. Such enhancement may derive from the injection of wave energy from the pickup ion source into the background turbulent cascade, and the injected wave energy is transferred across scales without leaving local enhancements in ${E}_{{{\rm{B}}}_{\perp }}$ or ${E}_{{{\rm{B}}}_{\mathrm{Tr}}}$ .

The physics potential of detecting ^8 B solar neutrinos will be exploited at the Jiangmen Underground Neutrino Observatory (JUNO), in a model-independent manner by using three distinct channels of the charged current (CC), neutral current (NC), and elastic scattering (ES) interactions. Due to the largest-ever mass of ^13 C nuclei in the liquid scintillator detectors and the expected low background level, ^8 B solar neutrinos are observable in the CC and NC interactions on ^13 C for the first time. By virtue of optimized event selections and muon veto strategies, backgrounds from the accidental coincidence, muon-induced isotopes, and external backgrounds can be greatly suppressed. Excellent signal-to-background ratios can be achieved in the CC, NC, and ES channels to guarantee the observation of the ^8 B solar neutrinos. From the sensitivity studies performed in this work, we show that JUNO, with 10 yr of data, can reach the 1 σ precision levels of 5%, 8%, and 20% for the ^8 B neutrino flux, ${\sin }^{2}{\theta }_{12}$ , and ${\rm{\Delta }}{m}_{21}^{2}$ , respectively. Probing the details of both solar physics and neutrino physics would be unique and helpful. In addition, when combined with the Sudbury Neutrino Observatory measurement, the world's best precision of 3% is expected for the measurement of the ^8 B neutrino flux.

As the concentration of fine particles (PM _2.5 ) is declining, ozone (O _3 ) concentration has been increasing in China in recent years. To collaboratively control PM _2.5 and O _3 , it is critical to understand the relationship between the two and identify major controlling factors. We use a convergent cross-mapping method to detect the causal relationship between daily PM _2.5 and maximum daily 8 h average (MDA8) O _3 concentrations in Beijing, Taizhou, Shenzhen and Chengdu, China, in the four seasons in 2015–2021. In addition, we also examined causal effects of atmospheric oxidation capacity, precursors and meteorological elements on PM _2.5 and MDA8 O _3 in the four cities. PM _2.5 and MDA8 O _3 are strongly positively correlated and show bidirectional causal relationships during the Beijing and Taizhou summer and in the four seasons in Shenzhen, due mainly to the strong photochemical reactions in the daytime. During the Beijing winter, PM _2.5 and MDA8 O _3 show bidirectional causal relationships, but the two are significantly negatively correlated, driven by NO _2 and relative humidity. Weak bidirectional, unidirectional and no causal effects between PM _2.5 and MDA8 O _3 are detected in other seasons in the four cities. In these seasons and cities, the top three causal factors of PM _2.5 differ from those of MDA8 O _3 . Season-, city- and pollutant-specific control measures of PM _2.5 and MDA8 O _3 are required.

Zinc (Zn) is considered a promising biodegradable metal for implant applications due to its appropriate degradability and favorable osteogenesis properties. In this work, laser powder bed fusion (LPBF) additive manufacturing was employed to fabricate pure Zn with a heterogeneous microstructure and exceptional strength-ductility synergy. An optimized processing window of LPBF was established for printing Zn samples with relative densities greater than 99% using a laser power range of 80 ∼ 90 W and a scanning speed of 900 mm s ^−1 . The Zn sample printed with a power of 80 W at a speed of 900 mm s ^−1 exhibited a hierarchical heterogeneous microstructure consisting of millimeter-scale molten pool boundaries, micrometer-scale bimodal grains, and nanometer-scale pre-existing dislocations, due to rapid cooling rates and significant thermal gradients formed in the molten pools. The printed sample exhibited the highest ductility of ∼12.1% among all reported LPBF-printed pure Zn to date with appreciable ultimate tensile strength (∼128.7 MPa). Such superior strength-ductility synergy can be attributed to the presence of multiple deformation mechanisms that are primarily governed by heterogeneous deformation-induced hardening resulting from the alternative arrangement of bimodal Zn grains with pre-existing dislocations. Additionally, continuous strain hardening was facilitated through the interactions between deformation twins, grains and dislocations as strain accumulated, further contributing to the superior strength-ductility synergy. These findings provide valuable insights into the deformation behavior and mechanisms underlying exceptional mechanical properties of LPBF-printed Zn and its alloys for implant applications.

Due to its powerful capability and high efficiency in big data analysis, machine learning has been applied in various fields. We construct a neural network platform to constrain the behaviors of the equation of state of nuclear matter with respect to the properties of nuclear matter at saturation density and the properties of neutron stars. It is found that the neural network is able to give reasonable predictions of parameter space and provide new hints into the constraints of hadron interactions. As a specific example, we take the relativistic mean field approximation in a widely accepted Walecka-type model to illustrate the feasibility and efficiency of the platform. The results show that the neural network can indeed estimate the parameters of the model at a certain precision such that both the properties of nuclear matter around saturation density and global properties of neutron stars can be saturated. The optimization of the present modularly designed neural network and extension to other effective models is straightforward.

A significant waste, including dyes in water, is generated during textile industrial processes, which causes environmental challenges. Herein, various nanocomposites (NC) of nickel oxide (NiO) and zinc oxide (ZnO) were prepared by solvothermal assisted green method where ethanolic extract of spinach leaves were used as a green source. The ultraviolet-visible (UV–vis) spectroscopy revealed that the band gap energies and absorption maxima of NiO/ZnO were 2.25 eV and 371 nm for 1:1 NC, 2.07 eV and 380 nm for 5:1 NC, and 2.02 eV and 385 nm for 1:5 NC. Ultraviolet-visible (UV–vis) spectroscopy, x-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) were employed to investigate the optical and structural characteristics of the NCs. The XRD patterns of NiO/ZnO NCs (i.e., 1:1, 5:1, 1:5) displayed crystallite sizes of 44.6, 52.17, and 42.5 nm, respectively. Associations of different functional groups with the surfaces of NC was confirmed by FTIR. Batch method was used to conduct the NCs-mediated adsorption of methylene blue (MB), methyl red (MR), and methyl orange (MO). Furthermore, several factors, including dye concentration, contact time, and temperature that affected the sorption, are reported. Pseudo-first order and pseudo-second order kinetic models were utilized to examine the adsorption kinetics. For all the dyes studied, pseudo-first order is the one which fitted best to the kinetic data, based on regression coefficient (R ^2 ). Indeed, experimental data were found to follow the Langmuir model. The maximum uptake capacity (q _m ) of MB adsorbed on NiO/ZnO NC (1:1) was 370 mg g ^−1 which is higher compared to that of values reported in the literature. These findings report a dual method (i.e., solvothermal-green chemistry) contribute to the development of efficient and cost-effective methods for wastewater treatment and environmental remediation.

The detection of gravitational wave events has stimulated theoretical modeling of the formation and evolution of double compact objects (DCOs). However, even for the most studied isolated binary evolution channel, there exist large uncertainties in the input parameters and treatments of the binary evolution process. So far, double neutron stars (DNSs) are the only DCOs for which direct observations are available through traditional electromagnetic astronomy. In this work, we adopt a population synthesis method to investigate the formation and evolution of Galactic DNSs. We construct 324 models for the formation of Galactic DNSs, taking into account various possible combinations of critical input parameters and processes such as mass transfer efficiency, supernova type, common envelope efficiency, neutron star kick velocity, and pulsar selection effect. We employ Bayesian analysis to evaluate the adopted models by comparing with observations. We also compare the expected DNS merger rate in the galaxy with that inferred from the known Galactic population of pulsar-neutron star systems. Based on these analyses we derive the favorable range of the aforementioned key parameters.

Voyager 1 and 2 are only the two spacecraft that have arrived and passed through the heliospheric boundaries. Based on the plasma data from the Voyager 2 spacecraft, the electron quasi-thermal noise (QTN) is investigated by using of the electron population model consisting of a core with Maxwellian distribution and a halo with kappa distribution. The power spectra of the electron QTN is calculated at different heliocentric distances from 1 to 110 au. The parametric dependence of the QTN power spectra and the effective Debye length on the model parameters, such as the density ratio and temperature ratio of the halo to the core, kappa index and the antenna length, are discussed further. The results show that the electron QTN spectrum consists of a plateau in the low frequency band f < f _pt , a prominent peak at the plasma frequency f _pt , and a rapid decreasing part in the high frequency band f > f _pt . The QTN plateau level basically falls down outwards until the termination shock crossing at about 84 au, after which the plateau rebounds a little near the heliopause. Although the model parameters can be very variable, the QTN plateau level does not present more than the double change in a fairly wide range of the model parameters. The presented results can be useful for future deep-space explorations in the heliosphere and can provide valuable references for the design of onboard detectors.

Solar energy, as an environmentally sustainable power source, is gaining increasing popularity worldwide, driving a surge in the number of solar photovoltaic (PV) plants. China, which has a prominent role in this domain, requires continuous updates to its PV plant data for spatiotemporal analyses. However, there remains an absence of a comprehensive and timely dataset of PV plants across China, leaving PV installation dates and other crucial attributes for comprehensive analyses underexplored. This study leverages Sentinel-2 data as a primary source to propose an optimized deep learning approach for PV plant extraction in China. Statistical analyses of PV plant attributes, including its installation date, size, site slope, and site land cover, were implemented from multiple data sources. Comprehensive analyses were conducted to unravel their spatiotemporal development patterns in the 21st century. The results indicate that as of 2023, China boasts 4347 PV plants, collectively spanning 4146 km ^2 , which are predominantly concentrated in Northwest and North China. 2016 and 2017 marked substantial growth in China’s PV plants, while other years exhibited stability. These plants exhibit the distinct spatial characteristics of installing smaller PV plants on flat terrain covered by vegetation or barren land. Over time, a notable trend in the installation of China’s PV plants has been the increasing preference for establishing larger ones in smooth terrain, with a focus on preventing damage to natural resources. The results reveal China’s optimization of PV plant site selection and construction strategies, aligning with global environmental goals and sustainable energy practices.

Ground-level ozone (O _3 ), renowned for its adverse impacts on human health and crop production, has garnered significant attention from governmental and public sectors. To address the limitations posed by sparse and uneven ground-level O _3 observations, this study proposes an innovative method for hourly full-coverage ground-level O _3 estimation using machine learning. Meteorological data from National Centers for Environmental Prediction global forecasting system, satellite data from Fengyun-4 A(FY-4 A) and Ozone Monitoring Instrument, emission inventory from Multi-resolution Emission Inventory for China, and other auxiliary data are utilized as input variables, while ground-based O _3 observations serve as the response variable. The method is applied on a monthly basis across China for the year 2022, resulting in the generation of an hourly full-coverage high-resolution (4 km) ground-level O _3 estimation, termed ML-derived-O _3 . Cross-validation results demonstrate the robustness of ML-derived-O _3 yielding a coefficient of determination ( R ^2 ) of 0.96 (0.91) for sample-based (site-based) evaluations and a root-mean-square error (RMSE) of 9.22 (13.65) µ g m ^−3 . However, the date-based evaluation is less satisfactory due to the imbalanced training data, resulting from the pronounced daily variations in ground-level O _3 concentrations. Nevertheless, the seasonal and hourly ML-derived-O _3 exhibits high prediction accuracy, with R ^2 values surpassing 0.95 and RMSE remaining below 7.5 µ g m ^−3 . This study marks a significant milestone as the first successful attempt to obtain hourly full-coverage ground-level O _3 data across China. The diurnal variation of ML-derived-O _3 demonstrates high consistency with ground-based observations, irrespective of clear or cloudy days, effectively capturing ground-level O _3 pollution exposure events. This novel estimation method will be employed to establish a long-term high spatial-temporal resolution ground-level O _3 dataset, which holds valuable applications for air pollution monitoring and environmental health research in future endeavors.

It has been more than 30 years since the enigmatic 21 μ m emission feature was first discovered in protoplanetary nebulae (PPNs). Although dozens of different dust carrier candidates have been proposed, there is as yet no widely accepted one. We present the results of molecular observations toward 21 μ m objects using the 10 m Submillimeter Telescope of Arizona Radio Observatory in the 1.3 mm band and the 13.7 m telescope of Purple Mountain Observatory in the 3 mm band, aiming to investigate whether the gas-phase environments of these unusual sources have some peculiarities compared to normal PPNs. We detect 31 emission lines belonging to seven different molecular species, most of which are the first detection in 21 μ m PPNs. The observations provide clues to the identification of the 21 μ m feature. We report a correlation study between the fractional abundance of gas-phase molecules and the strengths of the 21 μ m emission. Our study shows that, given the small sample size, the 21 μ m feature has weak or no correlations with the gas-phase molecules. Future radio observations of high spatial and spectral resolution toward a large sample are desirable to elucidate the 21 μ m emission phenomena.

To observe meteorite ablation, simulation experiments were conducted on the L5 ordinary chondrite and IAB-MG iron meteorites in an arc-heated facility and three flight conditions were reproduced. To mimic the high heating rates and the significant shear stress that meteorites experience during Earth entry, the samples were machined into 9° spherical cones with a 20 mm nose radius. High-quality video, the surface temperature, a time-resolved spectrum, and infrared video were recorded. The atom species were determined via spectroscopy to analyze the ablation products. Due to the electrode erosion and dissociation of air, the atomic lines of copper, nitrogen, and oxygen were detected in all the tests. Although the copper atom is a pollutant to the flow field, the five copper lines were used to determine the flow-field temperature. The ablation rates and effective heat of ablation of both the samples were measured under different conditions. The results indicate that shear stress is the dominant factor influencing meteorite ablation. Furthermore, the diversity between stony and iron meteorites suggests that the mass loss of stony meteorites depends on the fragmentation of the main body and that of iron meteorites depends on the shearing loss of the molten layer. Then, the fusion crusts were analyzed, the microstructures of the samples were obtained, the crust thicknesses were measured, and the elemental distribution of the stony meteorites was determined via energy dispersion spectroscopy. The study results explain the differences in the ablation and recrystallization process between stony and iron meteorites.

ZrB _2 -SiC ceramics are potential candidates for thermal protection materials for re-entry and hypersonic vehicles. Phases are typically added to ZrB _2 -SiC to enhance the oxidation resistance of the material. MoAlB is an attractive nanolaminated ternary boride compound. Due to its damage tolerance, crack healing ability, and good oxidation resistance, MoAlB is a promising material for high-temperature applications. Therefore, the effect of MoAlB substitution on the oxidation of ZrB _2 -SiC at 1600 °C for 10 h was evaluated. Five samples with different MoAlB contents (0 vol%, 4 vol%, 8 vol%, 12 vol%, 16 vol%) were prepared. The results indicate that ZrB _2 -SiC-8vol%MoAlB exhibits improved oxidation resistance compared to ZrB _2 -SiC. After being oxidized at 1600 °C for 10 h, the thickness of the oxide layer on ZrB _2 -SiC-8vol%MoAlB was significantly smaller than that on ZrB _2 -SiC. The thickness of the oxide layer in ZrB _2 -SiC was 250 μ m, while the thickness of the oxide layer in ZrB _2 -SiC-8vol%MoAlB was 108 μ m. The formation of dendritic crystals on the surface of ZrB _2 -SiC-4vol%MoAlB destroys the oxide layer, leading to a decrease in the oxidation resistance of material. The mass gain of ZrB _2 -SiC-12vol%MoAlB and ZrB _2 -SiC-16vol%MoAlB is greater, and the oxidation layer is thicker, indicating a lower oxidation resistance.

Some quasi-thermal (QT)-dominated gamma-ray bursts (GRBs) could be well described by a multicolor blackbody (mBB) function or a combined model of a BB plus a nonthermal (NT) component. In this analysis, two QT radiation-dominated bursts with known emission properties (GRB 210610B, likely from a hybrid jet, and GRB 210121A, with a spectrum consistent with nondissipative photospheric emission from a pure hot fireball) are used to make a comparison between these two models. To diagnose the magnetization properties of the central engine, the “top-down” approach proposed by Gao and Zhang is adopted. It is found that diagnoses based on these two models provide similar conclusions qualitatively; however, the model with mBB (or mBB+NT) may give more reasonable physical explanations. This implies that impacts from the GRB jet structure and geometrical broadening on the observed spectrum should be considered. However, conservatively, these methods may be not sensitive enough to distinguish between a pure hot fireball and a mildly magnetized hybrid jet. Some other information is necessary to provide more evidence when determining the jet properties for similar GRBs. Based on these considerations, we suggest that the photospheric emission of GRB 221022B is from a hot jet, where dissipation is caused by an internal shock mechanism due to the increasing Lorentz factor with time, which makes its prompt emission display typical evolution from thermal to NT.

The Parker Solar Probe (PSP) provides us with an unprecedentedly close approach to the observation of the Sun and hence the possibility of directly understanding the elementary process that occurs on the kinetic scale of particles' collective interaction in solar coronal plasmas. We report a type of weak solar radio burst (SRB) that was detected by PSP when it passed a low-density magnetic channel during its second encounter phase. These weak SRBs have a low starting frequency of ∼20 MHz and a narrow frequency range from a few tens of MHz to a few hundred kHz. Their dynamic spectra display a strongly evolving feature of the intermediate relative drift rate decreasing rapidly from above 0.01 s ^−1 to below 0.01 s ^−1 . Analyses based on common empirical models of solar coronal plasmas indicate that these weak SRBs originate from a heliocentric distance of ∼1.1–6.1 R _S (the solar radius), a typical solar wind acceleration region with a low- β plasma, and that their sources have a typical motion velocity of ∼ v _A (Alfvén velocity) obviously lower than that of the fast electrons required to effectively excite SRBs. We propose that solitary kinetic Alfvén waves with kinetic scales could be responsible for the generation of these small-scale weak SRBs, called solitary wave radiation.

Fire emits hazardous air pollutants, the most dominant of which is fine particulate matter of diameter ⩽2.5 μ m (PM _2.5 ). PM _2.5 is a great concern due to its adverse effects on public health. Previous studies have examined the health burden from fire-related PM _2.5 for the historical period; however, future global mortality associated with fire-PM _2.5 , particularly under the coexisting impacts of climate and socioeconomic changes, is yet to be projected. Here, we estimated the mortality associated to fire-PM _2.5 (fire-PM _2.5 mortality) for the present period (2010s) and then projected the mortality for the 2050s and 2090s under 10 scenarios created by combining two Representative Concentration Pathways (RCP2.6 or 6.0) with five Shared Socioeconomic Pathways (SSP1–5). We used the Li-Park fire model in combination with a chemical transport model and health risk assessment to calculate fire-PM _2.5 mortality. For the present period, the estimated fire-PM _2.5 mortality was 135 180 (105 403–163 738), which is 1.7 deaths per 100 000 population globally. When countries were grouped by income, the fire-PM _2.5 mortality rate was the highest in the high-income country group and lowest in the lowest-income country group. For the 2050s and 2090s, the fire-PM _2.5 mortality rate was projected to decrease under most scenarios because of decreases in fire emissions and baseline mortality rate. However, a scenario of high population growth and low technical development (SSP3) together with severe global warming (RCP6.0) would lead to an increase in the fire-PM _2.5 mortality rate in the 2090s, particularly in the highest-income countries, due to increased fire under drier and warmer weather conditions. Stratification of countries by gross domestic product indicated the need for adaptation efforts in the highest-income countries to avoid future increases of mortality associated with fire-PM _2.5 .

The traditional von Neumann computing architecture has relatively-low information processing speed and high power consumption, making it difficult to meet the computing needs of artificial intelligence (AI). Neuromorphic computing systems, with massively parallel computing capability and low power consumption, have been considered as an ideal option for data storage and AI computing in the future. Memristor, as the fourth basic electronic component besides resistance, capacitance and inductance, is one of the most competitive candidates for neuromorphic computing systems benefiting from the simple structure, continuously adjustable conductivity state, ultra-low power consumption, high switching speed and compatibility with existing CMOS technology. The memristors with applying MXene-based hybrids have attracted significant attention in recent years. Here, we introduce the latest progress in the synthesis of MXene-based hybrids and summarize their potential applications in memristor devices and neuromorphological intelligence. We explore the development trend of memristors constructed by combining MXenes with other functional materials and emphatically discuss the potential mechanism of MXenes-based memristor devices. Finally, the future prospects and directions of MXene-based memristors are briefly described.

The nucleation of iodic acid (HIO _3 ) and iodous acid (HIO _2 ) play a significant role in marine new particle formation (NPF) events. However, the inability to explain intensive NPF bursts in polluted coasts indicates the participation of potential precursors. Herein, we identified a novel nucleation mechanism of HIO _3 –HIO _2 system enhanced by the urban pollutant sulfuric acid (H _2 SO _4 ). We found that H _2 SO _4 could largely enhance the cluster formation rates ( J , cm ^−3 s ^−1 ) of HIO _3 –HIO _2 system, especially in high [H _2 SO _4 ] regions near H _2 SO _4 emission sources. The enhanced J of HIO _3 –HIO _2 –H _2 SO _4 system performs better match than that of HIO _3 –HIO _2 system with the observational rates of polluted coasts and polar regions, such as Zhejiang and Marambio. Moreover, the H _2 SO _4 -involved cluster formation is realized without Gibbs free energy barrier and dominate broadly in marine regions with rich H _2 SO _4 and scarce iodine concentrations. These findings may help to explain some missing fluxes of marine new particles and emphasize the impact of urban components on marine nucleation processes.

A negative capacitance (NC) effect has been proposed as a critical pathway to overcome the ‘Boltzmann tyranny’ of electrons, achieve the steep slope operation of transistors and reduce the power dissipation of current semiconductor devices. In particular, the ferroic property in hafnium-based films with fluorite structure provides an opportunity for the application of the NC effect in electronic devices. However, to date, only a transient NC effect has been confirmed in hafnium-based ferroic materials, which is usually accompanied by hysteresis and is detrimental to low-power transistor operations. The stabilized NC effect enables hysteresis-free and low-power transistors but is difficult to observe and demonstrate in hafnium-based films. This difficulty is closely related to the polycrystalline and multi-phase structure of hafnium-based films fabricated by atomic layer deposition or chemical solution deposition. Here, we prepare epitaxial ferroelectric Hf _0.5 Zr _0.5 O _2 and antiferroelectric ZrO _2 films with single-phase structure and observe the capacitance enhancement effect of Hf _0.5 Zr _0.5 O _2 /Al _2 O _3 and ZrO _2 /Al _2 O _3 capacitors compared to that of the isolated Al _2 O _3 capacitor, verifying the stabilized NC effect. The capacitance of Hf _0.5 Zr _0.5 O _2 and ZrO _2 is evaluated as −17.41 and −27.64 pF, respectively. The observation of the stabilized NC effect in hafnium-based films sheds light on NC studies and paves the way for low-power transistors.