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Nonmetallic pipelines are promising for medium-short distance hydrogen transport due to their lightweight, corrosion resistance, and durability. However, their low conductivity raises electrostatic safety concerns, given hydrogen’s exceptionally low ignition energy (0.017 mJ). This study employs electrostatic double-layer theory to quantify electrostatic risks under varying parameters, such as conductivity of nonmetallic materials, flow velocity, pipe diameter, and operating parameters including hydrogen pressure and temperature. The results indicate that lower electrical conductivity of nonmetallic materials, higher flow velocity and larger pipe diameter will increase the accumulation of static electricity. However, the accumulated static electricity energy in nonmetallic pipelines remains significantly below the minimum ignition potential of hydrogen, indicating a lower static electricity risk in nonmetallic pipelines. In addition, the static electricity risks of pipelines with different transportation media and pipeline materials were compared. Considering factors such as pipe surface roughness, electrical conductivity, and the ignition energy of the transportation medium, nonmetallic hydrogen pipelines exhibit lower static electricity risks. Existing applications have never reported electrostatic accidents in nonmetallic hydrogen pipelines, which also indicates that nonmetallic hydrogen pipelines have lower electrostatic risks. The results in this study could provide guidance for the application and safety evaluation of nonmetallic pipelines for hydrogen transportation.

ABSTRACT Carbon electrocatalyst materials based on lignocellulosic biomass with multi‐components, various dimensions, high carbon content, and hierarchical morphology structures have gained great popularity in electrocatalytic applications recently. Due to the catalytic deficiency of neutral carbon atoms, the usage of single lignocellulosic‐based carbon materials in electrocatalysis involving energy storage and conversion presents unsatisfactory applicability. However, atomic‐level modulation of lignocellulose‐based carbon materials can optimize the electronic structures, charge separation, transfer processes, and so forth, which results in substantially enhanced electrocatalytic performance of carbon‐based catalysts. This paper reviews the recent advances in the rational design of lignocellulosic‐based carbon materials as electrocatalysts from an atomic‐level perspective, such as self/external heteroatom doping and metal modification. Then, through systematic discussion of the design principles and reaction mechanisms of the catalysts, the applications of the prepared lignocellulosic‐based catalysts in rechargeable batteries and electrocatalysis are reviewed. Finally, the challenges in improving the catalytic performance of lignocellulosic‐based carbon materials as electrocatalysts and the prospects in diverse applications are reviewed. This review contributes to the synthesis strategy of lignocellulose‐based carbon electrocatalysts via atomic‐level modulation, which in turn promotes the lignocellulose valorization for energy storage and conversion. Carbon electrocatalyst materials based on lignocellulosic biomass with multi‐components, various dimensions, high carbon content, and hierarchical morphology structures have gained popularity in electrocatalytic applications. This review highlights the recent advances in the rational design of lignocellulosic‐based carbon electrocatalysts from an atomic‐level perspective, providing insights into the challenges and prospects of lignocellulose‐based carbon electrocatalysts and enhancing awareness of biomass valorization.

Understanding the failure mechanism of the rock mass under the general stress state is of great importance for the safe constructions of the underground engineering. Here, a series of true triaxial fracture tests on the intact and pre-flawed sandstones are conducted. The failure modes of the sandstones are analyzed, and the multi-scale fracture characteristics of the basic types of cracks are identified. Moreover, a multi-scale observation and crack statistics based method for analyzing the failure mechanism of the rock is proposed, and the influences of the stress state and the pre-existing flaw on the rock failure mechanism are investigated. The results indicate that the rock failure mode is controlled by the true triaxial stress state and the pre-existing flaw. The crack quantities in the pre-flawed rocks are nearly always more than those in the intact rock. which indicates that pre-existing flaw has a significant promoting effect on the crack initiation and development. 7 types of basic crack in the rock failure modes are summarized. Based on the multi-scale fracture characteristics, the fracture mechanisms of the basic types of cracks are identified, and the fracture mechanisms of the seven basic type cracks are identified and divided into four categories. The quantity statistics of the cracks corresponding to different fracture mechanisms show that the rise of σ 3 can significantly reduce the percentage of the shear cracks, while the rise of σ 2 conduces to the increase of the percentage of the tensile crack. The pre-existing flaw has a promoting effect on the initiation of the tensile crack, however, the true triaxial stress is the decisive factor controlling the rock failure mechanism. In the discussion, the size effect of rock fracture and the correlation between true triaxial test and engineering application are analyzed. This work contributes to an improved understanding of the failure mechanism of rock and a potential means by which to guide the design and construction of underground engineering.

In this work, steam explosion (SE) was exploited as a potential hydrothermal-humification process of vegetable wastes to deconstruct their structure and accelerate their decomposition to prepare humified substances. Results indicated that the SE process led to the removal of hemicellulose, re-condensation of lignin, degradation of the cellulosic amorphous region, and the enhancement of thermal stability of broccoli wastes, which provided transformable substrates and a thermal-acidic reaction environment for humification. After SE treatment, total humic substances (HS), humic acids (HAs), and fulvic acids (FAs) contents of broccoli samples accounted for up to 198.3 g/kg, 42.3 g/kg, and 166.6 g/kg, and their purification were also facilitated. With the increment of SE severity, structural characteristics of HAs presented the loss of aliphatic compounds, carbohydrates, and carboxylic acids and the enrichment of aromatic structures and N-containing groups. Lignin substructures were proved to be the predominant aromatic structures and gluconoxylans were the main carbohydrates associated with lignin in HAs, both of their signals were enhanced by SE. Above results suggested that SE could promote the decomposition of easily biodegradable matters and further polycondensation, aromatization, and nitrogen-fixation reactions during humification, which were conducive to the formation of HAs.

Chemically activated biochars prepared from sorghum distillers grain using two base activators (NaOH and KOH) were investigated for their adsorption properties with respect to ammonium nitrogen from aqueous solution. Detailed characterizations, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetry (TG), and specific surface area analyses, were carried out to offer a broad evaluation of the prepared biochars. The results showed that the NaOH- and KOH-activated biochars exhibited significantly enhanced adsorption capacity, by 2.93 and 4.74 times, respectively, in comparison with the pristine biochar. Although the NaOH-activated biochar possessed larger specific surface area (132.8 and 117.7 m2/g for the NaOH- and KOH-activated biochars, respectively), the KOH-activated biochar had higher adsorption capacity owing to its much higher content of functional groups. The adsorption kinetics and isotherms of the KOH-activated biochar at different temperatures were further studied. The biochar had a maximum adsorption capacity of 14.34 mg/g at 45 °C, which was satisfactory compared with other biochars prepared using different feedstocks. The adsorption process followed pseudo-second-order kinetics, and chemical adsorption was the rate-controlling step. The equilibrium data were consistent with the Freundlich isotherm, and the thermodynamic parameters suggested that the adsorption process was endothermic and spontaneous. Consequently, this work demonstrates that chemically activated biochar from sorghum distillers grain is effective for ammonium nitrogen removal.

As a key signaling molecule network in the tumor immune microenvironment, cytokines mediate intercellular communication through mechanisms such as autocrine and paracrine, exhibiting a significant “double-edged sword” effect during tumor initiation and progression. The dynamic regulation of this dual effect is influenced by the dependence on concentration, the variability within the tumor immune microenvironment, and the stages of tumor progression, ultimately representing the prolonged co-evolutionary result between tumors and the immune system. Cytokines, as a vital element of the immune microenvironment within tumors, influence cancer promotion by creating intricate networks. Therefore, disrupting this balance to alter the tumor growth environment is of great significance for achieving tumor suppression. In terms of clinical translation, the combined strategy of cytokine therapy and immune checkpoint blockade therapy has significantly improved treatment efficacy by synergistically enhancing immune activation and relieving immune suppression. Meanwhile, approaches such as monoclonal antibodies and bispecific molecules targeting pro-tumor cytokines have provided new insights for overcoming therapeutic resistance. In-depth clarification of the molecular mechanisms underlying the dual effects of cytokines, and breaking through the limitations of single targets from a network perspective, will provide a new paradigm for cancer immunotherapy from basic mechanisms to clinical applications. This will promote the upgrading of targeting strategies towards “dynamic regulation and synergistic intervention,” ultimately improving the prognosis of cancer patients.

Electric vehicles (EVs) are increasing in number every year, and large-scale uncontrolled EV charging can impose significant load pressure on the power grid (PG), affecting its stability and economy. This paper proposes an EV charging strategy that considers user selectivity. The user’s selection strategy includes options for fast and slow charging types, as well as the choice of whether to comply with grid-controlled charging. Charging types are selected based on the ability to reach the desired state of charge (SOC), while compliance with grid-controlled charging is determined by comparing the unit charging cost (CC). An objective function is established to minimize the peak valley load difference (PVLD) rate of PGs and users’ CC. To achieve this, an improved non-dominated sorting whale optimization algorithm (INSWOA) is proposed which initializes the population through logistic mapping, introduces nonlinear convergence factors for position updates, and uses adaptive inertia weights to improve population diversity, enhance global optimization ability, reduce premature convergence, and improve solution accuracy. Finally, simulating distribution networks in a certain region, the results obtained from the INSWOA were compared with those from the non-dominated sorting whale optimization algorithm (NSWOA) and other algorithms. The comparisons demonstrated that the INSWOA significantly reduced the PVLD rate of the PG load and users’ CCs, highlighting its high practical value.

Recent studies have suggested the glymphatic system as a key mechanism of waste removal in the brain. Dynamic contrast-enhanced MRI (DCE-MRI) using intracisternally administered contrast agents is a promising tool for assessing glymphatic function in the whole brain. In this study, we evaluated the transport kinetics and distribution of three MRI contrast agents with vastly different molecular sizes in mice. Our results demonstrate that oxygen-17 enriched water (H 2 17 O), which has direct access to parenchymal tissues via aquaporin-4 water channels, exhibited significantly faster and more extensive transport compared to the two gadolinium-based contrast agents (Gd-DTPA and GadoSpin). Time-lagged correlation and clustering analyses also revealed different transport pathways for Gd-DTPA and H 2 17 O. Furthermore, there were significant differences in transport kinetics of the three contrast agents to the lateral ventricles, reflecting the differences in forces that drive solute transport in the brain. These findings suggest the size-dependent transport pathways and kinetics of intracisternally administered contrast agents and the potential of DCE-MRI for assessing multiple aspects of solute transport in the glymphatic system.

In this work, lignin fractionation is proposed as an effective approach to reduce the heterogeneity of lignin and improve the adsorption and recycle performances of lignin as a cationic dye adsorbent. By stepwise dissolution of enzymatic hydrolysis lignin in 95% and 80% ethanol solutions, three lignin subdivisions (95% ethanol-soluble subdivision, 80% ethanol-soluble subdivision, and 80% ethanol-insoluble subdivision) were obtained. The three lignin subdivisions were characterized by gel permeation chromatography (GPC), FTIR, 2D-NMR and scanning electron microscopy (SEM), and their adsorption capacities for methylene blue were compared. The results showed that the 80% ethanol-insoluble subdivision exhibited the highest adsorption capacity and its value (396.85 mg/g) was over 0.4 times higher than that of the unfractionated lignin (281.54 mg/g). The increased adsorption capacity was caused by the enhancement of both specific surface area and negative Zeta potential. The maximum monolayer adsorption capacity of 80% ethanol-insoluble subdivision by adsorption kinetics and isotherm studies was found to be 431.1 mg/g, which was much higher than most of reported lignin-based adsorbents. Moreover, the 80% ethanol-insoluble subdivision had much higher regeneration yield (over 90% after 5 recycles) compared with the other two subdivisions. Consequently, the proposed fractionation method is proved to be a novel and efficient non-chemical modification approach that significantly improves adsorption capacity and recyclability of lignin.

The fracture evolution and the strength characteristics of a jointed rock mass under hydro-mechanical coupling are key issues that affect the safety and stability of underground engineering. In this study, a kind of transparent rock-like resin was adopted to investigate the crack initiation and propagation modes of the 3D flaw under hydro-mechanical coupling. The influences of the water pressure and the flaw dip angle on the fracture modes of the 3D flaw and the strength properties of the specimen were analyzed. The experiment results indicated that under the initiation and propagation modes, the 3D flaw presented two types of modes: the low-water-pressure type and the high-water-pressure type. The increase in the water pressure had a significant promoting effect on the crack initiation and propagation, which changed the overall failure mode of the specimen. With the increase in the flaw dip angle, the critical growth length of the wing crack decreased and the initiation moment of the fin-like crack showed a hysteretic tendency. The influences of the water pressure on the crack initiation stress and failure strength had thresholds. When lower than the threshold, the crack initiation stress increased slightly and the failure strength decreased gradually with the increase in the water pressure. Once the threshold was exceeded, both the crack initiation stress and the failure strength decreased significantly with the increase in the water pressure. With the increase in the flaw dip angle, both the crack initiation stress and the failure strength showed a first decreasing and then increasing tendency. The lowest crack initiation stress and the failure strength were found for the specimen containing the 45° flaw, while the highest were found for the specimen containing the 75° flaw. This study helps to deepen the understanding of the fracture mechanism of the engineering rock mass under hydro-mechanical coupling and has certain theoretical and applied value in engineering design and construction safety.