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Laser wakefield acceleration (LWFA) promises compact accelerators toward the high-energy frontier. However, the approach to the 100 GeV milestone faces the obstacle of the long focal length required for optimal acceleration with high-power lasers, which reaches hundreds of meters for 10–100 PW lasers. The long focal length originates from optimal laser intensity required to avoid nonlinear effects and hence large spot size and Rayleigh length. We propose a “telescope” geometry in which a micro-plasma parabola (MPP) is coupled with a short-focal-length off-axis parabola, minimizing the focal length to the meter range for LWFA under optimized conditions driven by lasers beyond 1 PW. Full-dimensional kinetic simulations demonstrate the generation of a 9 GeV electron bunch within only 1 m optical length—only one-tenth of that required with the conventional approach with the same performance. The proposed MPP provides a basis for the construction of compact LWFAs toward single-stage 100 GeV acceleration with 100 PW class lasers.

Abstract Accelerating a free electron to high‐energy forms the basis for studying particle and nuclear physics. Here it is shown that the wave function of such an energetic electron can be further manipulated with the femtosecond intense lasers. During the scattering between a high‐energy electron and a circularly polarized laser pulse, a regime is found where the enormous spin angular momenta of laser photons can be efficiently transferred to the electron orbital angular momentum (OAM). The wave function of the scattered electron is twisted from its initial plane‐wave state to the quantum vortex state. Nonlinear quantum electrodynamics (QED) theory suggests that the GeV‐level electrons acquire average intrinsic OAM beyond ⟨l⟩∼100ℏ at laser intensities of 1020 W cm−2 with linear scaling. These electrons emit γ‐photons with two‐peak spectrum, which sets them apart from the ordinary electrons. The findings demonstrate a proficient method for generating relativistic leptons with the vortex wave functions based on existing laser technology, thereby fostering a novel source for particle and nuclear physics.

Micro-structured targets can be employed to enhance the coupling of laser energy to the high energy density plasma. Here we report on experimental measurement of enhanced proton beam energy from laser-driven micro-wire array (MWA) targets along the backward direction. An ultra-intense (∼2×1020W/cm2) laser pulse of ∼ 40 fs pulse duration interacts with the MWA structure and induces large population of energetic electrons. The enhanced sheath field efficiently accelerates protons both transversely and longitudinally. The spectrometers record proton cut-off energy of around 16 MeV and temperature 813keV along the backward direction, which is 20%−60% higher than that of a flat target under commensurate laser conditions. Comparison with particle-in-cell simulations suggests that the enhancement originates from the increased temperature and population of the hot electrons within the micro-wires. These measurements provide a direct probe of the high energy density plasma condition in laser-driven solid targets and a useful benchmark for further studies on laser-driven micro-structured targets.

Abstract A localized nanoparticle insertion scheme is developed to decouple electron injection from laser evolution in laser wakefield acceleration. Here we report the experimental realization of a controllable electron injection by the nanoparticle insertion method into a plasma medium, where the injection position is localized within the short range of 100 μm. Nanoparticles were generated by the laser ablation process of a copper blade target using a 3-ns 532-nm laser pulse with fluence above 100 J/cm2. The produced electron bunches with a beam charge above 300 pC and divergence of around 12 mrad show the injection probability over 90% after optimizing the ablation laser energy and the temporal delay between the ablation and the main laser pulses. Since this nanoparticle insertion method can avoid the disturbing effects of electron injection process on laser evolution, the stable high-charge injection method can provide a suitable electron injector for multi-GeV electron sources from low-density plasmas.

The performance of laser-driven ion accelerators is intimately linked to the structure of the target. Here, laser-proton acceleration from a 3D-printed microwire-array target boosts the conversion efficiency and cut-off energy compared to a flat foil.

Due to the harsh radiation environment produced by strong laser plasma, most of the detectors based on semiconductors cannot perform well. So, it is important to develop new detecting techniques with higher detection thresholds and highly charged particle resolution for investigating nuclear fusion reactions in laser-plasma environments. The Columbia Resin No. 39 (CR-39) detector is mainly sensitive to ions and insensitive to the backgrounds, such as electrons and photons. The detector has been widely used to detect charged particles in laser-plasma environments. In this work, we used a potassium–ethanol–water (PEW) etching solution to reduce the proton sensitivity of CR-39, by raising the detection threshold for the research of laser-induced 11B(p, α)2α reaction. We calibrated the 3–5 MeV α particles in an etching condition of 60°C PEW-25 solution (17% KOH + 25%C2H5OH + 58%H2O) and compared them with the manufacturer’s recommended etching conditions of 6.25 N NaOH aqueous solution at 98°C in our laser-induced nuclear reaction experiment. The results indicate, with the PEW-25 solution, that CR-39 is more suitable to distinguish α tracks from the proton background in our experiment. We also present a method to estimate the minimum detection range of α energy on specific etching conditions in our experiment.

Laser-accelerated electrons are promising in producing gamma-photon beams of high peak flux for the study of nuclear photonics, obtaining copious positrons and exploring photon–photon interaction in vacuum. We report on the experimental generation of brilliant gamma-ray beams with not only high photon yield but also low divergence, based on picosecond laser-accelerated electrons. The 120 J 1 ps laser pulse drives self-modulated wakefield acceleration in a high-density gas jet and generates tens-of-MeV electrons with 26 nC and divergence as small as $1.51{}^{\circ}$ . These collimated electrons produce gamma-ray photons through bremsstrahlung radiation when transversing a high-Z solid target. We design a high-energy-resolution Compton-scattering spectrometer and find that a total photon number of $2.2\times {10}^9$ is captured within an acceptance angle of $1.1{}^{\circ}$ for photon energies up to $16\;\mathrm{MeV}$ . Comparison between the experimental results and Monte Carlo simulations illustrates that the photon beam inherits the small divergence from electrons, corresponding to a total photon number of $2.2\times {10}^{11}$ and a divergence of $7.73{}^{\circ}$ .

In quantum-electrodynamics scatterings the transfer of angular momentum between initial and final states can be resolved using the vortex scattering theory, where involved particles are described by quantum vortex states with featured orbital angular momentum (OAM). Here we employ the vortex scattering scenario in bremsstrahlung of a plane-wave electron by describing the final electron and photon in vortex states. We find that, while the total cross-section and angular distribution of the vortex scattering scenario are consistent with those from the ordinary plane-wave scattering, the final states in the former can gain non-negligible OAM values even though the incident electron does not contain any OAM. Moreover, introducing the OAM degree of freedom conserves the total angular momentum in polarized scattering. The dependence of the OAM on the opening angle of the vortex state and the energy ratio of photon to electron are obtained. It is shown that the emitted photon gains higher OAM at larger angles and energy ratios.

We explore radiative polarization of electrons in a standing-wave formed by two circularly-polarized laser pulses irradiating a thin layer. Here the electron radiative spin dynamics in external electromagnetic fields is described by the generalized Sokolov–Ternov model implemented in the particle-in-cell simulations. We find that significant polarization is established in roughly one laser period from the circular motion in the standing wave. However, such motion is unstable at the magnetic nodes such that electrons migrate to different phases. The beam polarization is then transferred to transverse directions following the T-BMT precession and splits into two groups with opposite signs. The induced polarization distribution allows for filtering out electron population of high polarization purity via certain emitting angles and energies, approaching maximum of 78% polarization at light intensities of the order ∼10 ^23 W cm ^−2 .

Particles in quantum vortex states (QVSs) carrying definite orbital angular momenta (OAM) bring different perspectives in various fundamental interaction processes. When unique properties arise in the QVS, understanding how OAM manifests itself between initial particles and the outcome in vortex particle collisions becomes essential. This is made possible by applying the complete vortex description for all involved particles such that angular momenta (AM) are represented by explicit quantum numbers and their connections are naturally retrieved. We demonstrate the full-vortex quantum-electrodynamics (QED) results for the Breit-Wheeler pair creation process and derive the AM-dependent selection rule. The numerically resolved cross sections show antisymmetric spin polarization and, most importantly, the OAM spectra in vortex collision processes. The latter reveals efficient conversion of OAM to created pairs, leading to featured hollow and ring-shaped structure in the density distribution. These results demonstrate a clear picture in understanding the AM physics in the scattering processes of high energy particles.

The acceleration of polarized electrons and protons in strong laser and plasma fields is a very attractive option to obtain polarized beams in the GeV range. We investigate the feasibility of particle acceleration in strong fields without destroying an initial polarization, taking into account all relevant mechanisms that could cause polarization losses, i.e. the spin precession described by the T-BMT equation, the Sokolov-Ternov effect and the Stern-Gerlach force. Scaling laws for the (de-)polarization time caused by these effects reveal that the dominant polarization limiting effect is the rotation of the single particle spins around the local electromagnetic fields. We compare our findings to test-particle simulations for high energetic electrons moving in a homogeneous electric field. For high particle energies the observed depolarization times are in good agreement with the analytically estimated ones.

We propose a new approach based on an all-optical set-up for generating relativistic polarized electron beams via vortex Laguerre-Gaussian (LG) laser-driven wakefield acceleration. Using a pre-polarized gas target, we find that the topology of the vortex wakefield resolves the depolarization issue of the injected electrons. In full three-dimensional particle-in-cell simulations, incorporating the spin dynamics via the Thomas-Bargmann Michel Telegdi equation, the LG laser preserves the electron spin polarization by more than 80% while assuring efficient electron injection. The method releases the limit on beam flux for polarized electron acceleration and promises more than an order of magnitude boost in peak flux, as compared to Gaussian beams. These results suggest a promising table-top method to produce energetic polarized electron beams.

We investigated transparency of near-critical plasma targets for highly intense incident lasers and discovered that beyond relativistic transparency, there exists an anomalous opacity regime, where the plasma target tend to be opaque at extreme light intensities. The unexpected phenomenon is found to originate from the trapping of ions under exotic conditions. We found out the propagation velocity and the amplitude of the laser-driven charge separation field in a large parameter range and derived the trapping probability of ions. The model successfully interpolates the emergence of anomalous opacity in simulations. The trend is more significant when radiation reaction comes into effect, leaving a transparency window in the intensity domain. Transparency of a plasma target defines the electron dynamics and thereby the emission mechanisms of gamma-photons in the ultra-relativistic regime. Our findings are not only of fundamental interest but also imply the proper mechanisms for generating desired electron/gamma sources.

An optical vortex with orbital angular momentum (OAM) enriches the light and matter interaction process, and helps reveal unexpected information in relativistic nonlinear optics. A scheme is proposed for the first time to explore the origin of photons in the generated harmonics, and produce relativistic intense harmonics with expected frequency and an optical vortex. When two counter-propagating Laguerre–Gaussian laser pulses impinge on a solid thin foil and interact with each other, the contribution of each input pulse in producing harmonics can be distinguished with the help of angular momentum conservation of photons, which is almost impossible for harmonic generation without an optical vortex. The generation of tunable, intense vortex harmonics with different photon topological charge is predicted based on the theoretical analysis and three-dimensional particle-in-cell simulations. Inheriting the properties of OAM and harmonics, the obtained intense vortex beam can be applied in a wide range of fields, including atom or molecule control and manipulation.

We propose a new acceleration scheme by employing the enormous electric potential behind a light-pressure-driven piston, namely ‘dragging field acceleration’. When a thin foil driven by light pressure of an ultra-intense laser pulse propagates in underdense background plasma, it serves as a shock-like piston, trapping and reflecting background protons to ultra-high energies. Unlike in shock wave acceleration, the piston velocity is not limited by the Mach number and can be highly relativistic. Background protons can be trapped and reflected forward by the ‘dragging field’ potential attached to a piston, which is not employed in light-pressure acceleration. Our one-dimensional particle-in-cell simulations and analytical model both show that proton energies of several tens to hundreds of GeV can be obtained. The injection conditions are investigated. Generation of mono-energetic tens-of-GeV proton bunch in two-dimensional geometry are discussed. Finally, the scheme is demonstrated with a three-dimensional simulation, where the effect of radiation reaction is included.

A new scheme for accelerating positively charged particles in a plasma-wakefield accelerator is proposed. If the proton drive beam propagates in a hollow plasma channel, and the beam radius is of order of the channel width, the space charge force of the driver causes charge separation at the channel wall, which helps to focus the positively charged witness bunch propagating along the beam axis. In the channel, the acceleration buckets for positively charged particles are much larger than in the blowout regime of the uniform plasma, and stable acceleration over long distances is possible. In addition, phasing of the witness with respect to the wave can be tuned by changing the radius of the channel to ensure the acceleration is optimal. Two-dimensional simulations suggest that, for proton drivers likely available in future, positively charged particles can be stably accelerated over 1 km with the average acceleration gradient of 1.3 GeV/m.

The interaction of a circularly polarized laser pulse with a mixed solid target containing two species of ions is studied by particle in cell simulations and analytical model. After the interaction tends to be stable, it is demonstrated that the acceleration is more efficient for the heavier ions than that in plasmas containing a single kind of heavy ion and the acceleration efficiency is higher when its proportion is lower. To obtain monoenergetic heavy-ion beams, a sandwich target with a thin mixed ion layer between two light ion layers and a microstructured target are proposed. The influences of parameters of the laser pulse and target on ion acceleration are discussed in detail. It is found that, when the target is thick enough, a cold target is more appropriate for heavy-ion acceleration than a warm target, and the velocity of the reflected heavy ions is proportional to the laser amplitude.

The thermal flux curve of phase-transition fluid (PF) was tested using differential scanning calorimetry, based on which a reaction kinetics model was established to reflect the relationship between phase transition conversion rate, temperature and time. A temperature field model for fractures and rock matrix considering phase transition heat was then constructed, and its reliability was verified using previously established temperature field models. Additionally, the new model was used to study the effects of different injection parameters and phase-transition fracturing performance parameters on the temperature variations in fractures and matrix. The study indicates that, at different positions and times, the cooling effect of the injected cold fluid and the exothermic effect during the phase transition alternately dominate the temperature within the fracture. At the initial stage of fracturing fluid injection, the temperature within the fracture is high, and the phase transition rate is rapid, resulting in a significant impact of exothermic phase transition on the reservoir rock temperature. In the later stage of injection, the fracture temperature decreases, the phase transition exothermic rate slows, and the cooling effect of the fracturing fluid on the reservoir rock intensifies. Phase transition heat significantly affects the temperature of the fracture. Compared to cases where phase transition heat is not considered, when it is taken into account, the temperature within the fracture increases to varying degrees at the end of fluid injection. As the phase transition heat increases from 20 J/g to 60 J/g, the maximum temperature rise in the fracture increases from 2.1 °C to 6.2 °C. The phase transition heat and PF volume fraction are positively correlated with fracture temperature changes, while specific heat capacity is negatively correlated with temperature changes. With increasing injection time, the temperature and phase transition rate at the fracture opening gradually decrease, and the location of the maximum phase transition rate and temperature difference gradually shifts from the fracture opening to about 10 m from the opening.

ABSTRACT Aims/Introduction Diabetes mellitus is a traditional risk factor for heart failure (HF), and glycated albumin (GA) is a marker to assess short‐term glycemic control. Whether GA has prognostic significance in patients with HF remains unclear. Materials and Methods A total of 717 patients with HF were enrolled in the prospective cohort study. Patients were grouped by the normal upper limit of GA (17%). Kaplan–Meier analysis and Cox proportional hazards regression were used to evaluate the association between GA and prognosis. Results During a mean follow‐up of 387 days, 232 composite endpoint events of hospitalization for HF or all‐cause death occurred. Kaplan–Meier analysis showed a higher rate of adverse events in the higher GA group (GA >17%; log‐rank test P 17%: HR 1.36, 95% CI 1.03–1.80, P = 0.032). Restricted cubic splines showed a linear association between GA and adverse events (P for non‐linearity = 0.231). There was no significant difference in adverse outcome risk between those with diabetes and GA ≤17% and those without diabetes, whereas the prognosis was worse in those with diabetes and GA >17% (HR 1.56, 95% CI 1.16–2.11, P = 0.004). Compared to the group with normal levels of GA and glycated hemoglobin, the group with GA >17% and glycated hemoglobin >6.5% had a higher risk of adverse events (HR 1.49, 95% CI 1.06–2.10, P = 0.022). Conclusions GA was an independent predictor of HF prognosis. Combining GA and glycated hemoglobin might improve the predictive power of adverse outcomes in patients with HF.

Abstract The Self-Propping Phase-transition Fracturing Technology (SPFT) represents a novel and environmentally friendly approach for a cost-effective and efficient development of the world’s abundant unconventional resources, especially in the context of a carbon-constrained sustainable future. SPFT involves the coupling of Thermal, Hydraulic, Mechanical, and Chemical (THMC) fields, which makes it challenging to understand the mechanism and path of hydraulic fracture propagation. This study addresses these challenges by developing a set of THMC multifield coupling models based on SPFT parameters and the physical/chemical characteristics of the Phase-transition Fracturing Fluid System (PFFS). An algorithm, integrating the Finite Element Method, Discretized Virtual Internal Bonds, and Element Partition Method (FEM-DVIB-EPM), is proposed and validated through a case study. The results demonstrate that the FEM-DVIB-EPM coupling algorithm reduces complexity and enhances solving efficiency. The length of the hydraulic fracture increases with the quantity and displacement of PFFS, and excessive displacement may result in uncontrolled fracture height. Within the parameters considered, a minimal difference in fracture length is observed when the PFFS amount exceeds 130 m3, that means the fracture length tends to stabilize. This study contributes to understanding the hydraulic fracture propagation mechanism induced by SPFT, offering insights for optimizing hydraulic fracturing technology and treatment parameters.

Underground salt cavern CO2 storage (SCCS) offers the dual benefits of enabling extensive CO2 storage and facilitating the utilization of CO2 resources while contributing the regulation of the carbon market. Its economic and operational advantages over traditional carbon capture, utilization, and storage (CCUS) projects make SCCS a more cost-effective and flexible option. Despite the widespread use of salt caverns for storing various substances, differences exist between SCCS and traditional salt cavern energy storage in terms of gas-tightness, carbon injection, brine extraction control, long-term carbon storage stability, and site selection criteria. These distinctions stem from the unique phase change characteristics of CO2 and the application scenarios of SCCS. Therefore, targeted and forward-looking scientific research on SCCS is imperative. This paper introduces the implementation principles and application scenarios of SCCS, emphasizing its connections with carbon emissions, carbon utilization, and renewable energy peak shaving. It delves into the operational characteristics and economic advantages of SCCS compared with other CCUS methods, and addresses associated scientific challenges. In this paper, we establish a pressure equation for carbon injection and brine extraction, that considers the phase change characteristics of CO2, and we analyze the pressure during carbon injection. By comparing the viscosities of CO2 and other gases, SCCS’s excellent sealing performance is demonstrated. Building on this, we develop a long-term stability evaluation model and associated indices, which analyze the impact of the injection speed and minimum operating pressure on stability. Field countermeasures to ensure stability are proposed. Site selection criteria for SCCS are established, preliminary salt mine sites suitable for SCCS are identified in China, and an initial estimate of achievable carbon storage scale in China is made at over 51.8–77.7 million tons, utilizing only 20%–30% volume of abandoned salt caverns. This paper addresses key scientific and engineering challenges facing SCCS and determines crucial technical parameters, such as the operating pressure, burial depth, and storage scale, and it offers essential guidance for implementing SCCS projects in China.

Sustainable agricultural management is one of the important factors for ensuring food security. In recent years, many wheat and maize fields on the Loess Plateau of China have been transformed into apple orchards for better economic returns. However, the evapotranspiration of apple orchards is far greater than the precipitation supply, resulting in a reduction in water resources that are available for apple trees. In this study, an experiment was conducted from 2012–2015 on apple orchards of different ages and maize and wheat fields. The field experiment and the Root Zone Water Quality Model (RZWQM2) were combined (1) to explore the feasibility of RZWQM2 in simulating soil water conditions under the three cropping systems and (2) to simulate long-term soil water dynamics and plant water use in different cropping systems from 1981–2019. The results showed that RZWQM2 was able to simulate the growth of wheat and maize and the water use of the three land use patterns (R2>0.70, −3.86 %0.89). Under the long-term continuous cropping system, the water consumption in the apple orchard was the highest, followed by that in the maize and wheat fields. The turning point of evapotranspiration in the apple orchard occurred at the 22nd year, but it decreased with increasing years of cultivation in the maize and wheat fields. Therefore, the planting of winter wheat after 22 years of apple planting should be considered to restore the soil water in the apple orchard to ensure the sustainable development of agriculture in this area.

Hydrogen, primarily produced from steam methane reforming, plays a crucial role in oil refining, and provides a solution for the oil and gas industry's long-term energy transition by reducing CO2 emissions. This paper examines hydrogen’s role in this transition. Firstly, experiences from oil and gas exploration, including in-situ gasification, can be leveraged for hydrogen production from subsurface natural hydrogen reservoirs. The produced hydrogen can serve as fuel for generating steam and heat for thermal oil recovery. Secondly, hydrogen can be blended into gas for pipeline transportation and used as an alternative fuel for oil and gas hauling trucks. Additionally, hydrogen can be stored underground in depleted gas fields. Lastly, oilfield water can be utilized for hydrogen production using geothermal energy from subsurface oil and gas fields. Scaling up hydrogen production faces challenges, such as shared use of oil and gas infrastructures, increased carbon tax for promoting blue hydrogen, and the introduction of financial incentives for hydrogen production and consumption, hydrogen leakage prevention and detection.

ObjectiveTo evaluate the safety of co-vaccination with domestic 23-valent pneumococcal polysaccharide vaccine (PPSV23) and split influenza virus vaccine (sFlu) in key populations aged 3 years and older and to provide a reference for formulating co-vaccination strategies. MethodsThe study participants were 5 502 healthy and unhealthy (with chronic diseases) volunteers (including 2 072 children aged 3 – < 8 years, 1 598 residents aged 8 – < 60 years, and 1 832 elderly aged 60 years and older) vaccinated simultaneously with one dose of PPSV23 (intramuscular injection into the deltoid muscle of the left upper arm) and one dose of sFlu (into the right upper arm) in 8 cities of Anhui province from October 2021 to February 2023. Active surveillance for adverse reactions within 28 days of co-vaccination with PPSV23 and sFlu was conducted among participants through active reporting via the Ark Immunization mobile application and telephone or home interviews by health care workers. Reported current/historic chronic diseases and observed adverse events after co-vaccination were categorized according to the Medical Dictionary for Regulatory Activities (MedDRA) and the Guiding Principles for the Classification of Adverse Events in Clinical Trials of Preventive Vaccines issued by the National Medical Products Administration. ResultsThe prevalence of underlying chronic diseases was 1.45%, 100.00%, and 37.61% in participants aged 3 – < 8, 8 – < 60, and ≥ 60 years, respectively. All adverse events occurred within 7 days of co-vaccination, with an incidence rate of 2.67%. The incidence rates of grade 1, 2, and 3 adverse events were 1.62%, 0.93%, and 0.13%, respectively. The incidence rates of local and systemic adverse events were 2.25% and 1.00%, respectively. Local reactions were mainly pain at the vaccination site, while systemic reactions were mainly fever. The incidence of local adverse events was higher for PPSV23 than for sFlu when administered at the same time. The incidence rates of adverse reactions in participants aged 3 – < 8, 8 – < 60, and 60 years and older were 2.03%, 3.25%, and 2.89%, respectively, without significant difference (χ2 = 5.741, P > 0.05). The grades of adverse reactions in the participants of the three age groups were mainly grade 1 and 2. The overall incidence rate of adverse reactions in healthy participants was 2.32% and that in unhealthy participants was 3.15%, without significant difference between the two groups (χ2 = 3.530, P > 0.05). There were no significant differences in the incidence and severity of adverse events between the healthy and unhealthy participants aged 3 – < 8 years and 60 years and older (P > 0.05). ConclusionSimultaneous vaccination with domestic PPSV23 and sFlu has shown good safety in key populations of different ages, health status and simultaneous vaccination with the two vaccines is recommended.

Hydrogen production via electrochemical water splitting demands high working voltages (>1.23 ​V) and hence incurs high electricity costs, encumbering its large-scale applications. The development of more high-efficiency and electricity-saving systems for hydrogen production is of great significance. Hydrazine oxidation reaction (HzOR)-assisted hydrogen production technology, which is constructed by replacing the anodic oxygen evolution reaction in pure water electrolysis systems with the HzOR, can greatly reduce the working voltage and electricity consumption, and hence shows great application prospects. In recent years, numerous studies have focused on designing various bifunctional electrocatalysts to simultaneously catalyze the cathodic and anodic reactions in HzOR-assisted hydrogen production systems. However, comprehensive reviews summarizing and commenting on this field are scarce. This review provides a systematic and insightful overview of the developments in HzOR-assisted hydrogen production technology from 2017 to the present, primarily focusing on catalyst design strategies, catalytic mechanisms, and economic and application analysis. Additionally, this review discusses several challenges and outlines future research directions in this field to attract more researchers' attention and accelerate the research and potential applications of HzOR-assisted hydrogen production technology.

Aqueous Zn-based energy storage (AZES) devices are promising candidates for large-scale energy storage systems. Nevertheless, AZES devices still face some critical bottlenecks and challenges, including poor chemical stability of Zn anode and a narrow operating voltage window of aqueous electrolyte. Zwitterions are typically organic salts in which cations and anions are covalently bonded. Zwitterionic materials have garnered considerable research attention in the field of electrochemical energy storage due to their solubility in polar solvents, strong hydration ability, and dipole formation for the transfer of carriers. Zwitterionic materials have been shown to achieve excellent effects on addressing the issues in AZES devices, yet the explorations with limited understanding of the functional mechanism and design basis of the zwitterionic materials. Accordingly, this review discusses the unique structure and characteristics of zwitterionic materials and summaries the applications and mechanisms of zwitterionic materials in AZES devices. Finally, the challenges and perspectives of zwitterionic materials working in the AZES devices optimization are offered for future research.

Abstract The ruminal microbiota generates biogenic methane in ruminants. However, the role of host genetics in modifying ruminal microbiota‐mediated methane emissions remains mysterious, which has severely hindered the emission control of this notorious greenhouse gas. Here, we uncover the host genetic basis of rumen microorganisms by genome‐ and transcriptome‐wide association studies with matched genome, rumen transcriptome, and microbiome data from a cohort of 574 Holstein cattle. Heritability estimation revealed that approximately 70% of microbial taxa had significant heritability, but only 43 genetic variants with significant association with 22 microbial taxa were identified through a genome‐wide association study (GWAS). In contrast, the transcriptome‐wide association study (TWAS) of rumen microbiota detected 28,260 significant gene–microbe associations, involving 210 taxa and 4652 unique genes. On average, host genetic factors explained approximately 28% of the microbial abundance variance, while rumen gene expression explained 43%. In addition, we highlighted that TWAS exhibits a strong advantage in detecting gene expression and phenotypic trait associations in direct effector organs. For methanogenic archaea, only one significant signal was detected by GWAS, whereas the TWAS obtained 1703 significant associated host genes. By combining multiple correlation analyses based on these host TWAS genes, rumen microbiota, and volatile fatty acids, we observed that substrate hydrogen metabolism is an essential factor linking host–microbe interactions in methanogenesis. Overall, these findings provide valuable guidelines for mitigating methane emissions through genetic regulation and microbial management strategies in ruminants.

Soil salinity in the Altay region presents a formidable challenge that greatly jeopardizes the sustainability of human agriculture. Thus, it is necessary to monitor the salinization of agricultural land in the region and assess the corresponding drivers. A random forest regression model was constructed using the Google Earth Engine platform and the accuracy of different image inversion models was compared to achieve precise large-scale spatial inversion and the dynamic monitoring of topsoil salinity. Furthermore, augmented regression tree models were utilized for the quantitative monitoring and analysis of salinity drivers. The feature importance ranking method identified six vegetation and salinity spectral indices (brightness index, enhanced normalized difference vegetation index, salinity index 2, the improved salinity monitoring index, and salinity index) to exert the most significant impact on salinity. A comparison of the random forest models constructed from Landsat and Sentinel-2 data revealed that the degree of soil salinization in the study area was more accurately predicted using the former, achieving an R2 value of 0.905 and RMSE value of 2.8 g/kg. A general decline was observed in the salinization of agricultural land in the Altay region between 2000 and 2010, with 52.36 % experiencing reduced salinization. However, mild and moderate salinization areas in the Fuhai and Altay regions expanded during this period, increasing by 267 km2 and 496.59 km2, respectively. Irrigation water gradually emerged as a pivotal factor influencing the spatial distribution of topsoil salinity in agricultural fields within the study area. Furthermore, following the transition from traditional water-saving to information-based efficient water-saving, the volume of irrigation water emerged as a pivotal factor impacting topsoil salinity in the study area, with a contribution rising from 11.4 % to 18.8 %, thus placing it as the most important factor influencing salinity. This work enhances the understanding of the trends and drivers of agricultural land salinization, which is of paramount significance for addressing national food security, efficiently utilizing saline land, and mitigating the escalation and spread of salinization.

The Proton Exchange Membrane (PEM) water electrolyzer is considered one of the promising energy storing means for harnessing variable renewable energy sources to produce hydrogen. Understanding the internal fluid dynamics, which are often challenging to directly observe experimentally, has prompted the use of numerical models to investigate two-phase flow within PEM water electrolyzers. In this study, we provide a comprehensive review of prior research focusing on two-phase modeling of PEM electrolyzers, encompassing both components at mesoscopic scales and the full electrolyzer at the macroscopic level. We delve into the specifics of various modeling approaches for two-phase flow at different scales and summarize and discuss the current state of the art in the field. Presently, two-phase models for the full electrolyzer predominantly employ a macroscopic homogeneous assumption. However, mesoscopic and microscopic models capable of tracking phase interfaces are limited to components. Challenges persist in integrating various modeling scales into a comprehensive electrolyzer model, particularly in coupling two-phase flow between the channels and porous media. Future efforts should focus on developing multi-scale models and simulating two-phase flow under fluctuating input conditions. Additionally, given the structural similarities between PEM water electrolyzers and PEM fuel cells, we compare and discuss differences in two-phase modeling between the two technologies. This work offers the insights for researchers in the field of modeling of PEM water electrolyzers and even fuel cells.

Abstract Utilizing energy storage in depleted oil and gas reservoirs can improve productivity while reducing power costs and is one of the best ways to achieve synergistic development of "Carbon Peak–Carbon Neutral" and "Underground Resource Utilization". Starting from the development of Compressed Air Energy Storage (CAES) technology, the site selection of CAES in depleted gas and oil reservoirs, the evolution mechanism of reservoir dynamic sealing, and the high-flow CAES and injection technology are summarized. It focuses on analyzing the characteristics, key equipment, reservoir construction, application scenarios and cost analysis of CAES projects, and sorting out the technical key points and existing difficulties. The development trend of CAES technology is proposed, and the future development path is scrutinized to provide reference for the research of CAES projects in depleted oil and gas reservoirs. Graphical abstract