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In-plane microsupercapacitors (MSCs) hold great promise for microscale power source, due to the extremely high power density and ultra-long cycling life. However, the scalable fabrication of flexible MSCs with high energy density remains a major challenge. Here, we demonstrate the fabrication of vanadium carbide/reduced graphene oxide (V 8 C 7 /rGO) MSCs via laser scribing on ammonium metavanadate/graphene oxide (NH 4 VO 3 /GO) films, prepared by efficient continuous centrifugal casting method. More than 20 MSCs can be produced on a flexible substrate in 30 min, showing the potential for scalable fabrication. The laser-induced V 8 C 7 /rGO shows highly porous microstructure, where vanadium carbide nanoparticles are in-situ synthesized and uniformly decorated on graphene nanosheets. The well-defined architecture endows V 8 C 7 /rGO MSCs with excellent electrochemical performance. The areal capacitance of these devices can be as high as 49.5 mF cm−2, 11 times higher than that of rGO MSCs. The volumetric energy density and power density can be up to 3.4 mWh cm−3 and 401 mW cm−3, respectively, competitive with the commercially available energy storage devices and most reported MSCs. In addition, V 8 C 7 /rGO MSCs show excellent flexibility and integrability, as well as long cycling life, promising for practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Aluminum battery systems are considered as a system that could supplement current lithium batteries due to the low cost and high volumetric capacity of aluminum metal, and the high safety of the whole battery system. However, first the use of ionic liquid electrolytes leading to AlCl4− instead of Al3+, the different intercalation reagents, the sluggish solid diffusion process and the fast capacity fading during cycling in aluminum batteries all need to be thoroughly explored. To provide a good understanding of the opportunities and challenges of the newly emerging aluminum batteries, this Review discusses the reaction mechanisms and the difficulties caused by the trivalent reaction medium in electrolytes, electrodes, and electrode–electrolyte interfaces. It is hoped that the Review will stimulate scientists and engineers to develop more reliable aluminum batteries. [ABSTRACT FROM AUTHOR]

Aluminiumbatteriesysteme werden infolge der geringen Kosten und der hohen volumetrischen Kapazität von Aluminiummetall sowie der hohen Sicherheit des gesamten Batteriesystems als eine mögliche Ergänzung für aktuelle Lithiumbatterien betrachtet. Bis dahin müssen jedoch z. B. die Verwendung von ionischen Flüssigkeiten als Elektrolyte, in denen AlCl4− anstelle von Al3+ vorliegt, verschiedene Interkalationsreagenzien, der langsame Diffusionsprozess im Feststoff sowie der rasche Kapazitätsverlust beim Zyklieren in Aluminiumbatterien gründlich untersucht werden. Um den Blick für die Möglichkeiten und Herausforderungen dieser neuartigen Aluminiumbatterien zu öffnen, diskutiert dieser Aufsatz die Reaktionsmechanismen sowie die Schwierigkeiten, die durch den dreiwertigen Ladungsträger in Elektrolyten, Elektroden und an den Elektroden‐Elektrolyt‐Grenzflächen verursacht werden. Wir möchten mit diesem Aufsatz Wissenschaftler und Ingenieure dazu anregen, zuverlässigere Aluminiumbatterien zu entwickeln. [ABSTRACT FROM AUTHOR]

• A phase-field model is constructed to simulate dynamic zinc dendrites growth. • Dendrite morphologies depend on ion transport and electrochemical reaction. • Flowing electrolyte uniformizes the concentration gradient on Zn anode surface. • Flowing electrolyte induces inhomogeneous deposition along the flow direction. The growth of zinc dendrites poses a major challenge in developing stable aqueous zinc batteries. It is crucial to understand the mechanism underlying dendrite growth and the influences of various factors on the process of dendrite growth. In this study, a phase field model is constructed to simulate the growth of zinc dendrite and investigate the temporal and spatial distributions of ions and electric potential in both static and flowing electrolytes. The influences of various critical factors, including overpotential, anisotropic strength and electrolyte flow rate, on the morphology evolution of electrodeposit are investigated. Results reveal that the surface morphology evolution is intimately dependent on the competition between ion transport and the electrochemical reaction, and it can be modulated by various parameters. In particular, flowing electrolyte not only enhances the convective ion transport but also suppresses the dendrite bifurcation on the surface, resulting in a uniform distribution of the concentration gradient and a compact deposit. However, nonuniformity induced by the flowing electrolyte from the inlet to outlet may impede the stable cycling of zinc anodes in the flow batteries. Therefore, further design and optimization of the flow field are desired for zinc-based flow batteries. This work provides insights into the growth process of zinc dendrites and the influences of several critical parameters, which could inform the design of stable aqueous zinc batteries. [Display omitted] [ABSTRACT FROM AUTHOR]

Lithium dendrites caused by nonuniform Li+ flux leads to the capacity fade and short‐circuit hazard of lithium metal batteries. The solid electrolyte interface (SEI) is critical to the uniformity of Li+ flux. Here, an ultrafast preparation of uniform and vertical Cu7S4 nano‐flake arrays (Cu7S4 NFAs) on the Cu substrate is reported. These arrays can largely improve the lithiophilicity of the anode and form Li2S‐enriched SEI due to the electrochemical reduction of Cu7S4 NFAs with lithium. A further statistical analysis suggests that the SEI, with a higher content of Li2S, is more effective to inhibit the formation of lithium dendrites and yields less dead lithium. A quite stable coulombic efficiency of 98.6% can be maintained for 400 cycles at 1 mA cm–2. Furthermore, at negative to positive electrode capacity ratio of 1.5 (N/P = 1.5), the full battery of Li@Cu7S4 NFAs||S shows 83% capacity retention after 100 cycles at 1 C, much higher than that of Li@Cu||S (33%). The findings demonstrate that high Li2S content in the SEI is crucial for the dendrite inhibition to achieve better electrochemical performance. [ABSTRACT FROM AUTHOR]

Neoplasms are one of the most concerned public health problems worldwide. Digestive system neoplasms, with a high morbidity and mortality, is one of the most common malignant tumors in human being. It is found that exosomes act as an intercellular communication media to carry the metabolic and genetic information of parental cells to target cells. Likely, exosomes participate in lipid metabolism and regulates multiple processes in digestive system neoplasms, including the information transmission among cancer cells, the formation of neoplastic microenvironment, and the neoplastic biological behaviors like metastasis, invasion, and the chemotherapy resistance. In this review, we firstly introduce the main mechanisms whereas exosomes act as intercellular lipometabolic communication mediator in digestive system neoplasms. Thereafter we introduce the relationship between exosomes lipid metabolism and various type of digestive system neoplasms, including gastric cancer, hepatocellular carcinoma, pancreatic cancer, and colorectal cancer. Eventually, we summarized and prospected the development and implication of exosomes in digestive system neoplasms. The further research of exosomes as intercellular lipid metabolism mediator will contribute to accurate and efficient diagnosis and treatment of digestive system neoplasms. [Display omitted] • Exosomes affect the development of digestive neoplasms through lipid metabolism. • Gastric cancer cell derived exo-lncFERO reduces the unsaturated fat in GCSCs. • Exosomes affect the lipid metabolism of HCC cell via miRNA signaling. • CRC cells-derived exosomes affect the development of CRC through lipid metabolism. [ABSTRACT FROM AUTHOR]

Deteriorating interfacial contact under mechanical deformation induces large cracks and high charge transfer resistance, resulting in a severe capacity fading of flexible lithium‐ion batteries (LIBs). Herein, an oxygen plasma treatment on a polymer separator combined with high‐speed centrifugal spraying to construct ultrastable interfacial contacts is reported. With the treatment, abundant hydrophilic oxygen‐containing functional groups are produced and ensure strong chemical adhesion between the separator and the active materials. With single walled carbon nanotubes (SWCNTs) sprayed onto the active materials, a dense thin film is formed as the current collector. Meanwhile, the centrifugal force caused by high‐speed rotation together with van der Waals forces under fast evaporation produces a much closer interface between the current collector and the active materials. As a result of this ultrastable interfacial interaction, the integrated electrode shows no structural failure after 5000 bending cycles with the charge‐transfer resistance as low as 35.8% and a Li‐ion diffusion coefficient nearly 19 times of the untreated electrode. Flexible LIBs assembled with these integrated electrodes show excellent structural and electrochemical stability, and can work steadily under various deformed states and repeated bending. This work provides a new technique toward rational design of electrode configuration for flexible LIBs. [ABSTRACT FROM AUTHOR]

Recycled aggregates (RA) are crushed materials derived from waste concrete or construction debris that play a crucial role in the recycling of construction waste resources. However, RA's irregular particle shape and surface cement paste adhesions limit its potential in pervious concrete applications. To overcome this limitation, the use of carbonation treatment methods to process RA and produce recycled aggregate pervious concrete (RAPC) was investigated. RA was subjected to a pre-carbonation treatment, followed by the production of RAPC mixtures using three slurry-to-aggregate ratios, carbonation curing, and two-step carbonation strengthening, which enhanced the physical and mechanical properties of the specimens. Then, the measurements including permeability coefficient, connected pore fraction, splitting tensile strength, and CT microstructure analysis were performed. A carbon footprint accounting system from "cradle to gate" was conducted to assess the specimens. Our results highlight that an increase in the slurry-to-aggregate ratio in RAPC mixtures results in enhanced mechanical properties but negatively affects permeability performance. By pre-carbonating RA, we significantly increase the pervious concrete's splitting tensile strength, up to 100%, and maintain the compactability while ensuring permeability performance (maximum 3.91% reduction for specimens with slurry-to-aggregate ratio of 0.3). The carbonation treatment method used in our study has ideal environmental effects, as it theoretically sequesters up to 58.12% of the total carbon emissions produced during the production process. • Dual-stage carbonation increase the strength of RAPC effectively. • Dual-stage carbonation has minimal impact on permeability performance of RAPC. • Dual-stage carbonation reduces the carbon footprint of pervious concrete by nearly 50%. [ABSTRACT FROM AUTHOR]

Abstract: The electrochemical performance of the aluminum‐sulfur (Al‐S) battery has very poor reversibility and a low charge/discharge current density owing to slow kinetic processes determined by an inevitable dissociation reaction from Al2Cl7− to free Al3+. Al2Cl6Br− was used instead of Al2Cl7− as the dissociation reaction reagent. A 15‐fold faster reaction rate of Al2Cl6Br− dissociation than that of Al2Cl7− was confirmed by density function theory calculations and the Arrhenius equation. This accelerated dissociation reaction was experimentally verified by the increase of exchange current density during Al electro‐deposition. Using Al2Cl6Br− instead of Al2Cl7−, a kinetically accelerated Al‐S battery has a sulfur utilization of more than 80 %, with at least four times the sulfur content and five times the current density than that of previous work. [ABSTRACT FROM AUTHOR]

Abstract: The electrochemical performance of the aluminum‐sulfur (Al‐S) battery has very poor reversibility and a low charge/discharge current density owing to slow kinetic processes determined by an inevitable dissociation reaction from Al2Cl7− to free Al3+. Al2Cl6Br− was used instead of Al2Cl7− as the dissociation reaction reagent. A 15‐fold faster reaction rate of Al2Cl6Br− dissociation than that of Al2Cl7− was confirmed by density function theory calculations and the Arrhenius equation. This accelerated dissociation reaction was experimentally verified by the increase of exchange current density during Al electro‐deposition. Using Al2Cl6Br− instead of Al2Cl7−, a kinetically accelerated Al‐S battery has a sulfur utilization of more than 80 %, with at least four times the sulfur content and five times the current density than that of previous work. [ABSTRACT FROM AUTHOR]

As a kind of hydraulic power component, the external gear pump determines the performance of the entire hydraulic system. The degradation state of gear pumps can be monitored by sensors. Based on the accelerated life test (ALT), this paper proposes a method to identify the wear degradation state of external gear pumps based on flow field analysis. Firstly, the external gear pump is theoretically analyzed. Secondly, dynamic grid technology is used to simulate the internal flow field of the gear pump in detail. Finally, the theoretical and simulation results are verified by the ALT. The results show that this method can effectively identify the wear degradation status of four sample pumps. The results of the work not only provide a solution to the research on the wear degradation of external gear pumps, but also provide strong technical support for the predictive maintenance of hydraulic pumps. [ABSTRACT FROM AUTHOR]