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Microcharcoal morphology, which changes with biofuel type in the wildfire, can be used as an index for wildfire history and vegetation evolution. Here, five loess sites across the Chinese Loess Plateau were used to establish the biofuel history of the region during the Holocene based on microcharcoal morphological records. The results suggested that consistently increasing grass biofuel dominated the mid‐Holocene (∼7,500–3,000 yr BP), and the grassland or steppe expanded in the same interval. Since the climate conditions with simultaneous high precipitation and temperature of the mid‐Holocene are the most recent paleoclimate analog for future warming, we argue that the humid and warm conditions expected under future global warming on the Loess Plateau might lead to an increase in the grass rather than trees. Plain Language Summary As the product of the incomplete combustion of plants, microcharcoal has been widely used as a wildfire indicator, though microcharcoal morphology has received little attention. Studies have recognized that microcharcoal morphology can indicate the biofuel type (grass or wood) burnt in wildfires and thus can be used as an ideal index in wildfire history and vegetation evolution research. Here, we shed new light on biofuel history based on this established relationship. We compiled 425 microcharcoal records from five sites across the Chinese Loess Plateau and combined the data with compiled pollen records to establish the vegetation history during the Holocene. The results suggest that grassland or steppe was prevalent during the mid‐Holocene, consistent with the synthesized herb pollen records, biome reconstruction, and high precipitation and temperature. Because the climate conditions of the mid‐Holocene are the most recent paleoclimate analog for future warming, we infer that the humid and warm conditions expected under future global warming may promote the expansion of grass vegetation on the Loess Plateau. The insights may reveal the vulnerability of the restoration achievements dominated by plantations today. In addition, we highlight the potential of the more easily preserved microcharcoal to explore vegetation history in future work. Key Points Microcharcoal morphological history reveals that grassland or steppe dominated the mid‐Holocene on the Chinese Loess Plateau The humid and warm conditions under future global warming on the Chinese Loess Plateau might lead to prevalent grass rather than trees Evidence suggests that more native grassland or steppe should be considered in future restoration programs on the Loess Plateau

The L-shell x-ray emission of tellurium induced by H 2 + ions impact is investigated in an energy range of 150–300 keV. The blue shifts of various L-subshell x rays and the enhancement of the relative intensity ratios of Lι, Lβ to Lα x ray are observed and interpreted by the multiple ionization of outer-shell electrons. The new experimental x-ray production cross sections, which almost correspond to those of protons with half of the original energy, are extracted and compared with various theoretical estimations. The correction effects of the united atom approximation and the multiple ionization atomic parameters are compared, and the influence of atomic parameters from different databases on the simulations is discussed. Overall, the ECUSAR-MI calculations using theoretical atomic parameters present the best agreement with the experiment results.

Intermolecular interactions involving aromatic rings are ubiquitous in biochemistry and they govern the properties of many organic materials. Nevertheless, our understanding of the structures and dynamics of aromatic clusters remains incomplete, in particular for systems beyond the dimers, despite their high presence in many macromolecular systems such as DNA and proteins. Here, we study the fragmentation dynamics of benzene trimer that represents a prototype of higher-order aromatic clusters. The trimers are initially ionized by electron-collision with the creation of a deep-lying carbon 2s −1 state or one outer-valence and one inner-valence vacancies at two separate molecules. The system can thus relax via ultrafast intermolecular decay mechanisms, leading to the formation of C 6 H 6 + ⋅ C 6 H 6 + ⋅ C 6 H 6 + trications and followed by a concerted three-body Coulomb explosion. Triple-coincidence ion momentum spectroscopy, accompanied by ab-initio calculations and further supported by strong-field laser experiments, allows us to elucidate the details on the fragmentation dynamics of benzene trimers. Higher-order aromatic clusters are prevalent in biochemical systems, but a full understanding of their structural and dynamical properties is lacking. Here, the authors demonstrate that inner-valence ionization can induce ultrafast relaxation and further fragmentation mechanisms in benzene trimers.

The art of decorating Chinese ceramic products is a precious cultural heritage. However, the illustration techniques used in ceramic decoration face challenges in terms of inheritance and protection due to limited transmission methods and low public awareness. In the era of artificial intelligence, traditional ceramic painting techniques are undergoing transformation. To address the lack of systematic guidance in ceramic painting pattern design and the uncertainty of desired design effects, an improved style transfer algorithm is proposed for decorating ceramic products. The algorithm utilizes the watershed algorithm to segment and extract pixels, ensuring shape consistency during the migration process. Additionally, local affine transformation preserves the integrity of points, lines, and surfaces. The designed improved style transfer algorithm is applied in practice, facilitating the design of ceramic cultural and creative products. This advancement simplifies the expression of decorative patterns in ceramic painting, promotes intelligent development in ceramic decoration design, and enables newcomers and the general public to engage in art creation, ultimately safeguarding and inheriting the techniques of ceramic decoration.

Intense particle beams generated from the interaction of ultrahigh intensity lasers with sample foils provide options in radiography, high-yield neutron sources, high-energy-density-matter generation, and ion fast ignition. An accurate understanding of beam transportation behavior in dense matter is crucial for all these applications. Here we report the experimental evidence on one order of magnitude enhancement of intense laser-accelerated proton beam stopping in dense ionized matter, in comparison with the current-widely used models describing individual ion stopping in matter. Supported by particle-in-cell (PIC) simulations, we attribute the enhancement to the strong decelerating electric field approaching 1 GV/m that can be created by the beam-driven return current. This collective effect plays the dominant role in the stopping of laser-accelerated intense proton beams in dense ionized matter. This finding is essential for the optimum design of ion driven fast ignition and inertial confinement fusion. A detailed understanding of particle stopping in matter is essential for nuclear fusion and high energy density science. Here, the authors report one order of magnitude enhancement of intense laser-accelerated proton beam stopping in dense ionized matter in comparison with currently used models describing ion stopping in matter.

FeCoCrNiAlMox (x = 0, 0.25, 0.5, 0.75, 1.0, molar ratio) alloy coatings were prepared on 2Cr13 steel substrates by wide-beam laser cladding, aiming to investigate the effects of different Mo addition amounts on the microstructure, phase composition, microhardness, and corrosion resistance of the coatings. The results show that all the coatings are of good quality without cracks or pores. Due to the dilution of the substrate, the actual composition of the coatings deviates from the designed composition to different degrees. The main constituent phase of different coatings was body-centered cubic solid solutions, which does not change with increasing Mo content. The middle part of the Mo0, Mo0.75, and Mo1.0 coatings consists of columnar crystal and Cr-rich needle-like precipitates, but the middle part of Mo0.25 and Mo0.5 coatings has a typical dendrite structure. There is not much difference in the alloy composition between dendrite and interdendrite, and the hardness and corrosion resistance of Mo0.25 and Mo0.5 coatings are basically the same. Among the coatings investigated in our study, the Mo1.0 coating has the greatest hardness and best corrosion resistance in 0.5 mol/L HCl solution.

Proton transfer underpins number of chemical and biochemical processes, yet its sub-100 fs dynamics have rarely been captured in real time. Here, we report direct and time-resolved observation of ionizing radiation-induced proton transfer in a heteroaromatic hydrate: the pyrrole-water complex. Both the electron-impact and strong-field laser experiments create a locally and doubly charged pyrrole unit (C 4 H 5 N 2+ ), which immediately (within 60 fs) donates a proton to the adjacent H 2 O, generating deprotonated C 4 H 4 N + and hydronium H 3 O + cations that subsequently undergo Coulomb explosion. The electron-impact experiments directly revealed initial states and provided dynamical insights through fragment ions and electron coincidence momentum imaging. The strong-field femtosecond laser experiments tracked the ultrafast dynamics of proton transfer; complementary ab initio calculations unraveled the dynamical details. The 50-60 fs proton transfer qualifies as one of the fastest acid-base reactions observed to date. This study offers a novel perspective on radiation-induced proton transfer in hydrated biomolecules. Proton transfer plays a key role in nature, yet its ultrafast dynamics remain elusive. Here the authors use coincidence spectroscopy and theoretical simulations to show that radiolytic doubly-ionized pyrrole triggers proton transfer to water within 60 fs.

The L-shell x-ray emissions of gold are investigated for the bombardment of high energy C 6+ ions in the high energy region of 154.3–423.9 MeV/u. Due to the multiple ionization of outer-shell electrons at the movement of L x-ray emission, the blue shift of the experimental x-ray energy and an enhancement of the relative intensity ratios of Lι, Lβ–Lα x rays are observed. Using the improved thin target formula and considering the effect of multiple ionization on atomic parameters, the L-subshell x-ray production cross sections are extracted from the counts and compared with the theoretical estimations of BEA, PWBA and ECPSSR. It is found that the relative corrections of ECPSSR on PWBA can be ignored in the present experimental energy region. The calculations of PWBA and ECPSSR are almost identical and both are larger than the experimental results. The BEA is in better agreement with the experiment as a whole.

An adaptive cruise control (ACC) system can improve safety and comfort during driving by taking over longitudinal control of the vehicle. It requires the coordination between the upper-layer controller and the lower-layer actuators. In this paper, a hierarchical anti-disturbance cruise control architecture based on electronic stability control (ESC) system is proposed. The upper-layer controller outputs the desired longitudinal acceleration or deceleration to the lower-layer actuators. In order to improve the accuracy of model prediction and achieve the coordinated control of multiple objectives, an upper-layer model prediction cruise controller is established based on feedback control and disturbance compensation. In addition, based on the hydraulic control unit (HCU) model and the vehicle longitudinal dynamics model, a lower-layer nonlinear model predictive deceleration controller is proposed in order to solve the problems of pressure fluctuations and the low accuracy of small decelerations when ESC is used as the actuator for the ACC system. Finally, the simulation and experimental tests were carried out. The results show that the proposed control architecture can improve the stability and comfort of the cruise control process. Moreover, compared with the traditional PID deceleration controller, it effectively improves the deceleration control accuracy.

The sideslip angle is crucial for the lateral stability state and stability control of intelligent commercial vehicles. However, sensors that can be used for direct measurements are often complex, expensive, and difficult to install in commercial vehicles. To estimate the vehicle sideslip angle, a state observer derived from the extended Kalman filter (EKF) method is proposed, and the state observer is estimated based on steering torque rather than steering angle. The transfer functions between the sideslip angle–steering torque and sideslip angle–steering angle are established, respectively, and the analysis shows that the steering torque signal has a more rapid and more direct reaction due to the hydraulic pressure in the steering system. Finally, the proposed method is validated using Simulink/TruckSim simulation hardware-in-the-loop bench test, and the results show that the proposed method can accurately reflect the actual state of the sideslip angle with good reliability and effectiveness.