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Investigating the extinction law in regions of high dust extinction, such as the Pillars of Creation within the M16 region, is crucial for understanding the densest parts of the interstellar medium (ISM). In this study, we utilize observations from the Near-Infrared Camera and the Mid-Infrared Instrument onboard the James Webb Space Telescope (JWST) to analyze the color-excess ratios E (F090W − λ )/ E (F090W − F200W) across a wavelength range of 0.9–7.7 μ m. Our method involves performing linear regression on color–color diagrams to derive these ratios. The enhanced detection capabilities of JWST data allow us to probe the distinct extinction law to the densest regions in M16 corresponding to an extinction depth up to A _V ∼ 60 mag. Remarkably, the resultant color-excess ratio curve exhibits a flatter profile than predicted by typical dust extinction models with R _V = 5.5 for dense ISM environments. Moreover, we observe that the mid-infrared extinction law diverges from the near-infrared power law, showing a tendency for the slope to flatten as the wavelength increases. These findings have significant implications for our understanding of the dust properties in dense interstellar environments.

In this paper, single-crystal GePb films were obtained by magnetron sputtering with high substrate temperature and rapid deposition rate. The GePb films have high crystalline qualities and smooth surface. The Pb content reached 1.29% and no segregation was observed. Based on this, a GePb based p–i–n photodetector was successfully prepared. The device showed a RT dark current density of 5.83 mA cm ^−2 at −1.0 V and a cutoff wavelength of 1990 nm, which covers all communication windows. At the wavelength of 1625 nm, responsivity of the photodetector reached 0.132 A W ^−1 at −1.0 V. The device demonstrates potential application in optical communications.

The far-infrared (FIR) opacity of dust in dark clouds within the Ophiuchus molecular cloud is investigated through multiwavelength infrared observations from UKIDSS, Spitzer, and Herschel. Employing the infrared color excess technique with both near-infrared and mid-infrared photometric data, a high-resolution extinction map in the K band ( A _K ) is constructed for three dark clouds: L1689, L1709, and L1712. The derived extinction map has a resolution of $1^{\prime} $ and reaches a depth of A _K ∼ 3 mag. The FIR optical depths τ _250 at a reference wavelength of 250 μ m are obtained by fitting the Herschel PACS and SPIRE continuum data at 100, 160, 250, 350, and 500 μ m using a modified blackbody model. The average dust opacity per unit gas mass at 250 μ m, r κ _250 , is determined through a pixel-by-pixel correlation of τ _250 with A _K , yielding a value of approximately 0.09 cm ^2 g ^−1 , which is about 2–3 times higher than the typical value in the diffuse interstellar medium. Additionally, an independent analysis across 16 subregions within the Ophiuchus cloud indicates spatial variations in dust opacity, with values ranging from 0.07 to 0.12 cm ^2 g ^−1 . Although the observed trend of increasing dust opacity with higher extinction implies grain growth, our findings indicate that rapid grain growth has clearly not yet occurred in the dark clouds studied in this work.

In tokamak disruptions where the magnetic connection length becomes comparable to or even shorter than the plasma mean-free-path, parallel transport can dominate the energy loss and the thermal quench of the core plasma goes through four phases (stages) that have distinct temperature ranges and durations. The main temperature drop occurs while the core plasma remains nearly collisionless, with the parallel electron temperature $T_{e\parallel}$ dropping in time t as $T_{e\parallel}\propto t^{-2}$ and a cooling time that scales with the ion sound wave transit time over the length of the open magnetic field line. These surprising physics scalings are the result of effective suppression of parallel electron thermal conduction in an otherwise bounded, quasineutral, and collisionless plasma, which is different from what are known to date on electron thermal conduction along the magnetic field in a nearly collisionless and quasineural plasma.

We have used the IRAM 30 m telescope to map some targets with HCO ^+ (1–0) and H ^13 CO ^+ (1–0) lines in order to search for evidence of gas infall in clumps. In this paper, we report the mapping results for 13 targets. All of these targets show HCO ^+ emissions, while H ^13 CO ^+ emissions are observed in 10 of them. The HCO ^+ integrated intensity maps of 10 targets show clear clumpy structures, and nine targets show clumpy structures in the H ^13 CO ^+ maps. Using the RADEX radiative transfer code, we estimate the column density of H ^13 CO ^+ , and we determine the abundance ratio [H ^13 CO ^+ ]/[H _2 ] to be approximately 10 ^−12 –10 ^−10 . Based on the asymmetry of the HCO ^+ line profiles, we identify 11 targets that show blue profiles, while six clumps have evidence of global infall. We use the RATRAN and two-layer models to fit the HCO ^+ line profiles of these infall sources, and analyze their spatial distribution of the infall velocity. The average infall velocities estimated by these two models are 0.24–1.85 km s ^−1 and 0.28–1.45 km s ^−1 , respectively. The mass infall rate ranges from approximately 10 ^−5 to 10 ^−2 M _⊙ yr ^−1 , which suggests that intermediate- or high-mass stars may be forming in the target regions.

The Pillars of Creation, one of the most recognized objects in the sky, are believed to be associated with the formation of young stars. However, so far, the formation and maintenance mechanism of the pillars are still not fully understood due to the complexity of the nonlinear radiation magnetohydrodynamics (RMHD). Here, assuming laboratory laser-driven conditions, we studied the self-consistent dynamics of pillar structures in magnetic fields by means of two-dimensional and three-dimensional (3D) RMHD simulations, and the results support our proposed experimental scheme. We find that only when the magnetic pressure and ablation pressure are comparable, the magnetic field can significantly alter the plasma hydrodynamics. For medium-magnetized cases ( β _initial ≈ 3.5), the initial magnetic fields undergo compression and amplification. This amplification results in the magnetic pressure inside the pillar becoming large enough to support the sides of the pillar against radial collapse due to pressure from the surrounding hot plasma. This effect is particularly pronounced for the parallel component ( B _y ), which is consistent with observational results. In contrast, a strong perpendicular ( B _x , B _z ) magnetic field ( β _initial < 1) almost retains its initial distribution and significantly suppresses the expansion of blown-off gas plasma, leading to the inability to form pillar-like structures. The 3D simulations suggest that the bending at the head of “Column I” in the Pillars of Creation may be due to nonparallel magnetic fields. After similarity scaling transformation, our results can be applied to explain the formation and maintenance mechanism of the pillars, and can also provide useful information for future experimental designs.

Advanced high-strength steels, such as quenching and partitioning (Q&P) steels, are of considerable interest in the automotive industry owing to their desirable mechanical properties. However, further research is required to elucidate the relationship between the microstructure and mechanical properties of Q&P steels. Therefore, this study investigated the microstructure, texture, and mechanical properties of Fe _0.23 C _1.55 Si _1.92 Mn _0.04 Al Q&P steel prepared under different conditions. After tensile deformation, the intensity of the H {001}〈110〉 orientation in the samples increased from 2.47 to 3.51. The sample partitioned at 375 °C for 60 s had the highest ultimate tensile strength of 1446 MPa. The sample partitioned at 450 °C for 180 s achieved the highest elongation at fracture of 17.7%. As the partitioning temperature (PT) increased, the width of the lath martensite increased, the volume fraction of primary martensite decreased, and the secondary martensite of the III sample increased. As the partitioning time (Pt) increased, the size and content of secondary martensite decreased.

High voltage circuit-breakers with superior performance are demanded as the transmission distance extends and voltage rises, which are often subject to high current and voltage surges. Commercial circuit-breaker contacts are conventionally manufactured with CuW alloy by infiltration method, limiting their performance improvement in withstanding current (or voltage) and lifespan. In this paper, we optimize the microstructure and component of Al _2 O _3 reinforced Cu@W80 composites (Al _2 O _3 /Cu@W80), which fabricates the Cu@W powder first by chemical coating and the composites by spark plasma sintering (SPS) method. The composites exhibit enhanced hardness (maximum value up to 273 HV) due to the addition of Al _2 O _3 powder and a more homogeneous and refined tungsten phase compared to the CuW counterpart. Moreover, the dispersed Al _2 O _3 particles with low work function become the preferred ablation phase and guide the electrical arcs, further improving the anti-arc erosion performance of Al _2 O _3 /Cu@W80. Our findings suggest that the Al _2 O _3 /Cu@W80 composite with optimized components could be potentially used as a candidate for high-voltage circuit-breaker contacts.

Zirconium carbide (ZrC _x ) is an important high temperature structural material, whose wide engineering applications are limited by carbon vacancies. Doping various impurity elements (O, B, etc) into ZrC _x may lead to a significant change in its mechanical properties and thermodynamic properties behaviors. In this paper, based on the density functional theory, the effects of carbon vacancy contents and dopant on mechanical properties and deformation behaviors of zirconium carbide were discussed. With the increase of the carbon vacancy contents, the Young’s modulus, bulk modulus, and shear modulus decrease gradually. When the tensile strain is greater than 0.4, ZrC _0.75 has stronger plasticity than ZrC _0.875 , ZrC _0.9375 and ZrC. Furthermore, the mechanical properties of ZrC, ZrC _0.75 O _0.25 , ZrC _0.75 B _0.25 and ZrC _0.75 were studied. Compared with ZrC _0.75 , the mechanical properties of ZrC _0.75 O _0.25 and ZrC _0.75 B _0.25 are improved, and the mechanical properties of the systems are improved the most by doping O atoms. Based on the quasi-harmonic approximation, the influence of doping atoms on thermodynamic properties of ZrC _0.75 O _0.25 , ZrC _0.75 B _0.25 and ZrC _0.75 was also investigated. Doping O and B atoms in ZrC _0.75 can improve the thermal conductivity at high temperature, and ZrC _0.75 B _0.25 has the highest thermal conductivity. The results also show that the thermal properties of ZrC _0.75 can be improved by doping O and B atoms. With the increase of temperature, ZrC _0.75 O _0.25 has the largest thermal expansion.

Co-doping is one of the most facile and efficient strategies for boosting the photocatalytic performance of g-C _3 N _4 . Herein, a series of Ti and O co-doped g-C _3 N _4 (Ti/OCN) composites with excellent photocatalytic inactivation activity of Enterobacter cloacae ( E. cloacae ) were successfully synthesized by simple calcination of urea/formic acid/TiCl _4 precursor. The obtained Ti/OCN-3 possessed the optimal photocatalytic capability with complete inactivation of 6.20 log CFU·ml ^−1 E. cloacae under 60 min of visible light irradiation. The improved photocatalytic disinfection performance was probably attributed to the synergistic effect of Ti and O co-doping, which led to an extended visible light response and accelerated charge transport efficiency. Furthermore, scavenger trapping and electron spin resonance (ESR) experiments revealed that ·O _2 ^− , h ^+ and ·OH were responsible for the enhanced inactivation activity. Overall, this research provided a promising strategy for fabricating g-C _3 N _4 -based catalysts to efficiently deal with the hazards of pathogenic microorganisms.

Superhydrophobic film with cauliflower-like structure was prepared on copper sheet by one-step electrodeposition method. The surface morphology and chemical composition of the superhydrophobic film were characterized by SEM, FTIR, XPS and contact angle measurements. Due to the cauliflower-like hierarchical structure and low surface energy, the as-prepared surface can reach up to a maximum contact angle of 158.3°, and the rolling angle is not more than 7°. Polarization curve was investigated using electrochemical workstation, and the as-prepared superhydrophobic surface showed improved corrosion resistance compared with bare copper.

For achieving tunable saturation magnetization and line width, different cations were doped into the YIG-based garnets, which the standard molecular formula could be expressed as A _3 [Fe _2−x M _x ](Fe _3−y N _y )O _12 . Most researchers have reported a single rule of one element doping (x or y) on its magnetic properties. However, the cooperation effect of x + y to the magnetic contribution was not clearly clarified. In this work, multi-doped bismuth-iron garnets {Bi _0.84 Ca _2.16 }[Fe _2−x In _x ](Fe _3−y V _y )O _12 (x = 0.72–0.14 and y = 1.24–1.38) with low saturation magnetizations (4 πM _s = 200–600 Gs at 298 K) were prepared by a conventional fluxing agent method. The cooperation effect of In ^3+ and V ^5+ co-doped into bismuth-iron garnets (BIG) on their structures and magnetic properties were systematically investigated using XPS, TEM and VSM. It could be found that the total doped concentration (x + y) was decreasing regardless of the increasing V concentration (y) and decreasing In concentration (x). As-synthesized BIG presented a well single-crystal structure, and the lattice spacing was decreasing with the decrease of x + y in accompanying with the transition of dislocations from point defects to edge dislocations. Both linear increase of Curie temperature and 4 πM _s with the decrease of x + y was revealed. The mechanism could be attributed that the doped non-magnetic ions could reduce the average nearest-neighbor coordination irons for oxygen ions and weaken the anti-ferromagnetic super-exchange interactions among the magnetic ions within the structure, namely dilution effect. By comparison, the total concentraions were higher than that of previous works, which the tailorable 4 πM _s of ferrite was not reported. Here we revealed the controllable 4 πM _s with higher total concentrations (x + y ≥ 1.52). These findings will be provided more opportunities for applications in microwave devices.

FeWB bulk and FeWB(001)/ α -Fe(111) interface were studied by first-principles calculations. FeWB bulk bonding has the mixed characteristics of metallicity, covalency and ionicity, among which the metallicity is the most obvious. Such combination endows FeWB with promising toughness and excellent electrical conductivity. Adhesion work, W _ad , was calculated for twelve different interfacial structures, taking into account four terminations of FeWB(001) and three stacking sequences. The B(Fe)-terminated center-site stacking interface is the most stable with the smallest interface distance and the largest W _ad . Fe-B and W-B bond lengths at the interface are even shorter than those in FeWB bulk. By comparing the interface fracture work G with W _ad , it is found that the interface fracture position has a certain occasionality, but it tends to occur in FeWB bulk. According to the results of density of states, we concluded the B(Fe)-terminated center-site stacking interface is a metallic/covalent mixing nature, while the combination of top-site stacking interface is mainly covalent bonds.

Variations in solar shortwave and thermal longwave radiation over the Tibetan Plateau (TP) are crucial for global climate and regional ecological environment. Previous radiation studies over the TP were widely based on ground and satellite measurements of the radiation budget at the surface and at the top of the atmosphere. A stratospheric balloon-based radiation measurement system was employed in a 2019 field campaign to study how and why radiation profiles vary over the TP during the Asian summer monsoon (ASM) period. We originally provide in situ measurements of multiwavelength radiation profiles from the surface up to the upper troposphere and lower stratosphere (UTLS) over the TP. These valuable observations, combined with simultaneous operational radiosondes, ground measurements, satellite retrievals and radiative transfer model simulations, are used to study radiation variations and the radiative forcings of clouds and aerosols over the TP during the ASM period. Cloud occurrences beneath the balloon flight altitude induce more balloon-borne shortwave upward radiation and ultraviolet upward radiation but less longwave upward radiation relative to clear sky counterparts. The radiative transfer model simulations capture the variations in balloon shortwave downward radiation (SDR) profiles well. Cloud radiative forcings at the UTLS and surface vary greatly with varying cloud cover. The diurnal evolution of the SDR discrepancy between the balloon altitudes and surface and the aerosol radiative forcing at the bottom of the atmosphere are also discussed during the balloon flight periods. The results of this study are expected to improve our understanding of radiation properties in the UTLS and help us better comprehend the thermal conditions associated with clouds and aerosols over the TP during the ASM.

TiAlCoCr _x FeNihigh-entropy alloys (HEAs) coatings were fabricated on the surface of Ti6Al4V by laser cladding. Their microstructural evolution with the increase in x value (x = 0, x = 1.0, x = 2.0) was investigated in detail. Besides that, the investigation into the effects of the Cr content on their corrosion behaviors and mechanical properties (in terms of hardness and wear resistance) was also carried out comprehensively. The results indicated that two kinds of phases (a solid solution with thehexagonal close-packed (HCP) structureand Ti _2 Ni) were synthesized in the coatings, and the HCP content was gradually increased with the increase in x accompanied with the decrease in Ti _2 Ni content. A HEA coating only composed of single HCP was successfully prepared when x reached 2.0. The electrochemical and immersion tests all confirmed that the coating with x = 2.0demonstrated the most excellent corrosion resistance in a0.1 mol·L ^−1 HCl solution from different aspects including corrosion tendency and corrosion rate without the applied potential, the formation difficult/stability of the passive film and the dissolution rate in the passive state, and corrosion surface morphology. The averagemicrohardness values of the coatings weregraduallyincreasedfrom 656HV _0.2 to 800 HV _0.2 with increasing xfrom 0 to 2.0, which wereabout double that of the substrate (350 HV _0.2 ). Wear resistance of the coatings also exhibited the upward tendency with increasing the x values (0.562 mm ^3 at x = 2.0, 0.640 mm ^3 at x = 1.0, 0.641 mm ^3 at x = 0 and 1.419 mm ^3 for the substrate). More Cr addition into the cladding material will contribute to the formation of a HEA coating composed of single HCPwith excellent corrosion and wear resistance.

The NiO/graphene (NiO/G) composite nanofibers were successfully synthesized by simple electrospinning followed by heat treatment. They as anode materials for lithium ion batteries demonstrated the more outstanding electrochemical performance when compared with the NiO + Ni composite nanofibers as the reference. NiO/G exhibited a higher discharging/charging capacity (about 712 mAh·g ^−1 at the third cycle) with a coulombic efficiency of nearly 100% than NiO + Ni (547 mAh·g ^−1 ). NiO/G also demonstrated the excellent cycling stability due to its higher discharging capacity of 571 mAh·g ^−1 and retention rate of 78% than NiO + Ni (184 mAh·g ^−1 and 33%) when subject to 50 cycles at 100 mA·g ^−1 . Moreover, its rate performance was also greatly improved when compared with NiO + Ni owing to its higher discharging capacity (305 mAh·g ^−1 , 556 mAh·g ^−1 ) and retention rate (44%, 80%) at the current density increased from 100 mA·g ^−1 to 2000 mA·g ^−1 , and then recovered to 100 mA·g ^−1 . The outstanding electrochemical performance of the NiO/G electrode is closely related to its lower ohmic resistance (2.1 Ω)/charge transfer resistance (86.5 Ω), and stronger diffusion capability of Li ^+ resulting from the high specific surface area, excellent conductivity and a certain charge storage capacity of graphene.

The continuous discharge of organic dye effluents from textile industries causes severe global water pollution. A sustainable and effective route needs to be developed for the treatment of textile effluent in order to enable environmental protection and water recycling. In particular, the nanomaterials-based photocatalytic degradation of organic compounds is a promising approach to minimize water pollution. Herein, a facile hydrothermal method was reported for the preparation of Zn _2 GeO _4 nanorods (NDs) with unique size, shape, and surface chemistry using sodium lauryl sulfate (SDS) as the surfactant. The crystal structure, size, and shape of the synthesized NDs were characterized by x-ray diffraction pattern (XRD) and field-emission scanning electron microscopy (FESEM). Initially, the XRD pattern revealed that SDS plays a crucial role in the formation of highly pure Zn _2 GeO _4 NDs with rhombohedral crystalline nature. It was clearly noticed that increasing SDS concentration results in the formation of Zn _2 GeO _4 NDs with decreased size ranges (100 nm). Conversely, the size of Zn _2 GeO _4 NDs increased at higher SDS concentrations. The photocatalytic activity of Zn _2 GeO _4 NDs was evaluated by the degradation of methyl orange (MO) in aqueous solution. Under light irradiation, the Zn _2 GeO _4 NDs prepared by using different concentrations of SDS exhibited varied photocatalytic performance. Among the tested samples, Zn _2 GeO _4 NDs prepared with 0.1 g of SDS showed the best photocatalytic activity with a MO decomposition rate of 94.6% within 60 min. This study suggests that SDS can be used to modulate the morphology and photocatalytic performance of Zn _2 GeO _4 NDs, and the resultant Zn _2 GeO _4 NDs can serve as a photocatalyst in wastewater treatment.

The electronic band structure and valley splitting of the WSe _2 /NiCl _2 heterostructure have been investigated by density functional theory and Berry curvature calculations. We demonstrate that the valley polarization of monolayer WSe _2 is induced due to the magnetic proximity effect caused by the single layer of ferromagnetic NiCl _2 . The magnitude of valley splitting depends on the stacking configurations of WSe _2 /NiCl _2 , and the maximum value of valley splitting reaches −11.87 meV. Large valley splitting can be achieved by adjusting the layer spacing and constructing a NiCl _2 /WSe _2 /NiCl _2 heterojunction with Ni spins arranged in parallel between two NiCl _2 sheets. The valley-contrasting Berry curvature between the K and K ′ valleys suggests that the WSe _2 /NiCl _2 -based heterostructure could potentially be used as a valleytronic device to realize the valley-polarized anomalous Hall effect as both spin and valley filter.

Compared with the TbF _3 grain boundary diffusion (GBD) magnet, in this study, Cu aided TbF _3 GBD was applied to Nd-Fe-B magnets to further improve the coercivity. It is found that the coercivity increased sharply from 17.42 kOe to 25.43 kOe when the diffusion source is the mix powders of Cu and TbF _3 , higher than 21.25 kOe with single TbF _3 as the diffusion source. The wettability of the grain boundary phases were improved owing to the accumulation of Cu in grain boundary. The grains were uniformly enveloped by grain boundary phase with the help of Cu addition. The microstructure analysis indicated that the diffusion depth of Tb increased significantly due to the modified grain boundaries which offered better tunnels for the diffusion of Tb.

Cooling techniques are essential to understand fundamental thermodynamic questions of the low-energy states of physical systems, furthermore they are at the core of practical applications of quantum information science. In quantum computing, this controlled preparation of highly pure quantum states is required from the state initialization of most quantum algorithms to a reliable supply of ancilla qubits that satisfy the fault-tolerance threshold for quantum error correction. Heat-bath algorithmic cooling has been shown to purify qubits by controlled redistribution of entropy and multiple contact with a bath, not only for ensemble implementations but also for technologies with strong but imperfect measurements. In this paper, we show that correlated relaxation processes between the system and environment during rethermalization when we reset hot ancilla qubits, can be exploited to enhance purification. We show that a long standing upper bound on the limits of algorithmic cooling Schulman et al (2005 Phys. Rev. Lett. 94 , 120501) can be broken by exploiting these correlations. We introduce a new tool for cooling algorithms, which we call ‘state-reset’, obtained when the coupling to the environment is generalized from individual-qubits relaxation to correlated-qubit relaxation. Furthermore, we present explicit improved cooling algorithms which lead to an increase of purity beyond all the previous work, and relate our results to the Nuclear Overhauser Effect.

The Bose–Hubbard model provides an excellent platform for exploring exotic quantum coherence. Interaction blockade is an important fundamental phenomenon in the two-site Bose–Hubbard system (BHS), which gives a full quantum description for the atomic Bose–Josephson junction. Using the analogy between the two-site BHS and the quadrupolar nuclear magnetic resonance (NMR) crystal, we experimentally simulate a two-site Bose–Hubbard system in a NMR quantum simulator composed of the quadrupolar spin-3/2 sodium nuclei of a NaNO _3 single crystal, and observe the interesting phenomenon of interaction blockade via adiabatic dynamics control. To our best knowledge, this is the first experimental implementation of the quantum simulation of the interaction blockade using quadrupolar nuclear system. Our work exhibits important applications of quadrupolar NMR in the quantum information science, i.e. a spin-3/2 system can be used as a full 2-qubit su(4) system, if the quadrupole moment is not fully averaged out by fast tumbling in the liquid phase.

The ability to post-select the outcomes of an experiment is a useful theoretical concept and experimental tool. In the context of weak measurements, post-selection can lead to surprising results such as complex weak values outside the range of eigenvalues. Usually post-selection is realized by a projective measurement, which is hard to implement in ensemble systems such as NMR. We demonstrate the first experiment of a weak measurement with post-selection on an NMR quantum information processor. Our setup is used for measuring complex weak values and weak values outside the range of eigenvalues. The scheme for overcoming the problem of post-selection in an ensemble quantum computer is general and can be applied to any circuit-based implementation. This experiment paves the way for studying and exploiting post-selection and weak measurements in systems where projective measurements are hard to realize experimentally.