Li‐rich Mn‐based (LRMO) cathode materials have attracted widespread attention due to their high specific capacity, energy density, and cost‐effectiveness. However, challenges such as poor cycling ...stability, voltage deca,y and oxygen escape limit their commercial application in liquid Li‐ion batteries. Consequently, there is a growing interest in the development of safe and resilient all‐solid‐state batteries (ASSBs), driven by their remarkable safety features and superior energy density. ASSBs based on LRMO cathodes offer distinct advantages over conventional liquid Li‐ion batteries, including long‐term cycle stability, thermal and wider electrochemical windows stability, as well as the prevention of transition metal dissolution. This review aims to recapitulate the challenges and fundamental understanding associated with the application of LRMO cathodes in ASSBs. Additionally, it proposes the mechanisms of interfacial mechanical and chemical instability, introduces noteworthy strategies to enhance oxygen redox reversibility, enhances high‐voltage interfacial stability, and optimizes Li+ transfer kinetics. Furthermore, it suggests potential research approaches to facilitate the large‐scale implementation of LRMO cathodes in ASSBs.
The prospects for commercialization of LRMO cathodes in ASSBs with high energy density are highly encouraging, which will develop new opportunities to overcome the energy density and safety limitations of conventional liquid batteries. Ongoing research and interdisciplinary efforts are expected to overcome omni‐direction challenges and propel LRMO cathodes toward practical applications in ASSBs significantly.
This paper presents a detailed investigation, via field experiment, into the mechanism of high-order polygonal wear of wheels of a new type of high-speed train. The investigation was carried out ...during the performance acceptance test of the train and its initial commercial operation. The investigation covered the performance acceptance test of 150 000 km and the commercial operation of about 150 000 km. In the performance acceptance test of the first stage of about 70 000 km, at 200-250 km/h with full loading and sometimes overloading by 30%, the serious polygonal wear of 23-order took place on all the wheels of the train, and was measured and analyzed in detail. All the potygonized wheels were re-profiled because the polygonal wear had caused strong vibration and damage to the train parts. After re-profiling, the vibration of the train and track and the wear status of the wheels were measured and analyzed at different test mileages according to the polygonal wear situation of the wheels. The measured vibration of the train includes the accelerations at different positions of a motor car and a trail car. The vibration modes of the key parts of the bogies of the two cars were calculated. Meanwhile, the track resonant frequencies were investigated at the site. The purpose of the above tests and analysis is try to find the frequency of work mode matching the passing frequency of the high-order wheel polygon. The present investigation shows that one of the working models causes the formation and development of the high-order wheel polygonal wear. The growth of this wear was effectively reduced through the frequent changing of the running speed of the train operating on the way back and forth every day.
We propose a snap-through triboelectric nanogenerator with magnetic coupling and buckled bistable mechanism to harvest rotational energy (ST-RTENG). The buckled bistable beam generates convex and ...concave snap-through under magnetic excitation, which can significantly increase the contact force of the functional materials of triboelectric nanogenerator (TENG), thereby significantly improving the electrical output. By adopting a magnetic coupling non-contact energy transfer mechanism, the drive part and the electromechanical conversion part are easily physically separated, which improves the robustness of the system in the harsh environment. The electromechanical coupling dynamic model of the system is established and verified by experiments. The different modes and key parameters of the magnet arrangement are investigated. The ST-RTENG with two pairs of magnets with staggered poles has a maximum voltage of 1235 V at a rotating speed of 150 r/min and a maximum average power of 778 μW at a rotating speed of 800 r/min. The prototype can light up more than 1000 LEDs under low speed excitation, and realize self-powered temperature monitoring and wireless transmission. The rotational energy harvester with magnetic coupling buckled bistable mechanism proposed in this paper can be used for wind energy harvesting in the field environment, self-powered state monitoring of the pressure pipelines, and other applications that require isolation of external excitation and electromechanical conversion components.
Display omitted
•A snap-through TENG with magnetic coupling buckled bistable mechanism is proposed.•The dynamic model of the system is established and verified experimentally.•The mode and key dimension parameters of the magnet arrangement are investigated.•The prototype can light up 1000 LEDs, and realize self-powered temperature monitoring.
Taking energy density and safety into account, the anode-free all-solid-state lithium battery is a strong candidate to surpass the capabilities of routine lithium-ion batteries. However, achieving ...uniform stable lithium metal plating under high areal capacity is a grand challenge facing practical applications of lithium metal batteries. We report a high-performance anode-free all-solid-state lithium battery with a current collector consisting of carbon-reinforced ionic-electronic composites. When an interconnected carbon paper is compounded with a solid electrolyte, a three-dimensional ionic-electronic conduction network can be achieved, affording a large number of sites and scalable spaces for the nucleation and growth of lithium metal. The composite layer can achieve a long cycle life (>5000 cycles), stable lithium metal plating with a high areal capacity (>8 mAh cm
−2
), which is significantly better than that of the copper current collectors for routine anode-free configurations. The application of high-areal-capacity (4 mAh cm
−2
) pouch cell provides an efficient and effective strategy for practical anode-free all-solid-state lithium batteries.
A three-dimensional carbon-reinforced ionic-electronic composite (CRIEC) boosts the cycling areal capacities of working anode-free all-solid-state lithium batteries.
Twenty target compounds were designed, synthesized and evaluated in terms of their biological activity.
Display omitted
Twenty benzothiazole derivatives bearing a 1,3,4-oxadiazole moiety were ...synthesized and evaluated for their anti-oxidant and anti-inflammatory activities. Among these compounds, 8h and 8l were appeared to have high radical scavenging efficacies as 0.05 ± 0.02 and 0.07 ± 0.03 mmol/L of IC50 values in ABTS+ bioassay, respectively. In anti-inflammatory tests, compound 8h displayed good activity with 57.35% inhibition after intraperitoneal administration, which was more potent than the reference drug (indomethacin). Molecular modeling studies were performed to investigate the binding mode of the representative compound 8h into COX-2 enzyme. In vitro enzyme study implied that compound 8h exerted its anti-inflammatory activity through COX-2 inhibition.
We report on a Kerr-lens mode-locked Tm,Ho-codoped calcium aluminate laser with in-band pumping of the Tm ions by a spatially single-mode 1678 nm Raman fiber laser. The structurally disordered ...CaGdAlO 4 host crystal is also codoped also with the passive Lu ion for additional inhomogeneous line broadening. The Tm,Ho,Lu:CaGdAlO 4 laser generates soliton pulses as short as 79 fs at a central wavelength of 2073.6 nm via soft-aperture Kerr-lens mode-locking. The corresponding average output power amounts to 91 mW at a pulse repetition rate of ∼86 MHz. The average output power can be scaled to 842 mW at the expense of slightly longer pulses of 155 fs at 2045.9 nm, which corresponds to a peak power of ∼58 kW. To the best of our knowledge, this represents the first demonstration of an in-band pumped Kerr-lens mode-locked Tm,Ho solid-state laser at ∼2 µm.
We report on sub-50 fs pulse generation from a passively mode-locked Yb:SrF 2 laser pumped with a spatially single-mode, fiber-coupled laser diode at 976 nm. In the continuous-wave regime, the Yb:SrF ...2 laser generated a maximum output power of 704 mW at 1048 nm with a threshold of 64 mW and a slope efficiency of 77.2%. A continuous wavelength tuning across 89 nm (1006 – 1095 nm) was achieved with a Lyot filter. By implementing a SEmiconductor Saturable Absorber Mirror (SESAM) for initiating and sustaining the mode-locked operation, soliton pulses as short as 49 fs were generated at 1057 nm with an average output power of 117 mW at a pulse repetition rate of ∼75.9 MHz. The maximum average output power of the mode-locked Yb:SrF 2 laser was scaled up to 313 mW for slightly longer pulses of 70 fs at 1049.4 nm, corresponding to a peak power of 51.9 kW and an optical efficiency of 34.7%.
In the present investigation, a series of dihydrotriazine derivatives-bearing 5-aryloxypyrazole moieties were synthesized and their structures were confirmed by different spectral tools. The ...biological evaluation in vitro revealed that some of the target compounds exerted good antibacterial and antifungal activity in comparison with the reference drugs. Among these novel hybrids, compound
10d
showed the most potent activity with minimum inhibitory concentration values (MIC) of 0.5 µg/mL against
S. aureus
4220, MRSA 3506 and
E. coli
1924 strain. The cytotoxic activity of the compounds
6d
,
6m
,
10d
and
10g
was assessed in MCF-7 and HeLa cells. Growth kinetics study showed significant inhibition of bacterial growth when treated with different conc. of
10d
. In vitro enzyme study implied that compound
10d
exerted its antibacterial activity through DHFR inhibition. Moreover, significant inhibition of biofilm formation was observed in bacterial cells treated with MIC conc. of
10d
as visualized by SEM micrographs.
Graphic abstract
Twenty-nine target compounds were designed, synthesized and evaluated in terms of their antibacterial and antifungal activities.
