High Peak Research Articles

Holocene vegetation, fire, climate dynamics and human impact in the upper Orkhon Valley of the Khangai Mountains, Mongolia

The Upper Orkhon Valley, located in the Khangai Mountains of Central Mongolia, is mainly covered by a forest-steppe ecosystem. This is an interesting area to study because its vegetation dynamics might have been influenced by climatic and anthropogenic drivers. This study investigates the dynamics of vegetation (pollen), human activity (pollen and NPP) and fire activity (macro-charcoal) from a lacustrine sediment core from lake Shireet Naiman Nuur, covering the last 7400 cal yr BP. The results of the pollen analysis showed a continual and constant decline of tree species in favour of the development of grasslands. Fire activity was more intense (high peak magnitude) during the mid Holocene, while it became more frequent but less intense from 5000 cal yr BP onwards, when herbaceous taxa became more present. The NPP analysis suggest that the study site was free of human activity from 7400 to 3500 cal yr BP, whereas the traces of the development of human societies that took place in the Orkhon Valley, such as pastoralism and grazing activities, have been demonstrated by the increase in coprophilous fungi and the Poaceae Cerealia-type pollen around 3200 cal yr BP, although its impact seems to have remained low.

Peaks, sources, and immediate health impacts of PM2.5 and PM1 exposure in Indonesia and Taiwan with microsensors.

Microsensors have been used for the high-resolution particulate matter (PM) monitoring. This study applies PM and health microsensors with the objective of assessing the peak exposure, sources, and immediate health impacts of PM2.5 and PM1 in two Asian countries. Exposure assessment and health evaluation were carried out for 50 subjects in 2018 and 2019 in Bandung, Indonesia and for 55 subjects in 2019 and 2020 in Kaohsiung, Taiwan. Calibrated AS-LUNG sets and medical-certified RootiRx® sensors were used to assess PM and heart-rate variability (HRV), respectively. Overall, the 5-min mean exposure of PM2.5 and PM1 was 30.4 ± 20.0 and 27.0 ± 15.7 µg/m3 in Indonesia and 14.9 ± 11.2 and 13.9 ± 9.8 µg/m3 in Taiwan, respectively. The maximum 5-min peak PM2.5 and PM1 exposures were 473.6 and 154.0 µg/m3 in Indonesia and 467.4 and 217.7 µg/m3 in Taiwan, respectively. Community factories and mosquito coil burning are the two most important exposure sources, resulting in, on average, 4.73 and 5.82 µg/m3 higher PM2.5 exposure increments for Indonesian subjects and 10.1 and 9.82 µg/m3 higher PM2.5 exposure for Taiwanese subjects compared to non-exposure periods, respectively. Moreover, agricultural waste burning and incense burning were another two important exposure sources, but only in Taiwan. Furthermore, 5-min PM2.5 and PM1 exposure had statistically significantly immediate impacts on the HRV indices and heart rates of all subjects in Taiwan and the scooter subjects in Indonesia with generalized additive mixed models. The HRV change for a 10 µg/m3 increase in PM2.5 and PM1 ranged from -0.9% to -2.5% except for ratio of low-high frequency, with greater impacts associated with PM1 than PM2.5 in both countries. This work highlights the ability of microsensors to capture high peaks of PM2.5 and PM1, to identify exposure sources through the integration of activity records, and to assess immediate changes in heart rate variability for a panel of approximately 50 subjects in Indonesia and Taiwan. This study stands out as one of the few to demonstrate the immediate health impacts of peak PM, complementing to the short-term (days or weeks) or long-term effects (months or longer) assessed in most epidemiological studies. The technology/methodology employed offer great potential for researchers in the resource-limited countries with high PM2.5 and PM1 levels.

A de-texturing model for enhancing the accuracy of centroid positioning

In tasks guided by microvision, extracting centroids is a common method for positioning, which is negatively affected by texture. Here, an attention-related de-texturing model is proposed to eliminate the texture of microparts and preserve accurate edges. A network with an attention module called De-texturing Net is built, in which both the transformer and channel attention modules are included. Considering the importance of texture, the additional factor in loss function is constructed based on the Gram matrix difference between target images and generated images. Results show that De-texturing Net can generate de-texturized images with high Peak Signal to Noise Ratio/SSIM, indicating the similarity between de-texturized and target images. Moreover, for the centroid positioning, the error in de-texturized images is significantly lower than the error in original images. This study helps improve the accuracy of centroid positioning due to the de-texturized images with accurate edges.

Investigation of compound occurrence of storm surge and river flood in Mikawa Bay, Japan, using typhoon track ensemble experiments

The risk of high river flow and peak storm surge superimposing in the estuary of small-and medium-sized rivers can be more severe during typhoon landfalls than at other times. In this study, 30 cases of typhoon track ensemble experiments for five rivers in Mikawa Bay, Japan, were evaluated using an atmospheric-river-ocean model. The results showed that storm surges coincided with high river flows when typhoons crossed the western side of Mikawa Bay, with the highest potential observed when typhoons passed northwest of the Bay. The average time discrepancy for the five rivers between the storm surge occurrence and increased river flow in the minimum time difference case was 48 min at the river mouth. Distinct trends in the time difference between a storm surge and river flow were observed for each river mouth. The order of time differences corresponded to the drainage area scale: Toyo (188 min), Umeda (112 min), Otowa (114 min), Sana (96 min), and Yagyu (88 min). Time difference trends also varied based on the distance between the typhoon center and each river mouth. For Toyo River, storm surges and high river flows did not substantially overlap, regardless of distance. However, for medium-and small-sized rivers, the time difference increased proportionally with the distance from the typhoon. The Yagyu River showed the highest potential for compound occurrence of a storm surge and river flood because of the synchronization of storm surge peaks and high river flow peaks, with a time difference of 1–2 h for small-and medium-sized rivers within 100 km2 of the basin.

Líĺwat Climbers Could See the Ocean from the Peak of Qẃelqẃelústen: Evaluating Oral Traditions with Viewshed Analyses from the Mount Meager Volcanic Complex Prior to Its 2360 BP Eruption

Abstract Among Líĺwat people of the Interior Plateau of British Columbia, an oral tradition relays how early ancestors used to ascend Qẃelqẃelústen, or Mount Meager. The account maintains that those climbers could see the ocean, which is not the case today, because the mountain is surrounded by many other high peaks, and the Strait of Georgia is several mountain ridges to the west. However, the mountain is an active and volatile volcano, which last erupted circa 2360 cal BP. It is also the site of the largest landslide in Canadian history, which occurred in 2010. Given that it had been a high, glacier-capped mountain throughout the Holocene, much like other volcanoes along the coastal range, we surmise that a climber may have reasonably been afforded a view of the ocean from its prior heights. We conducted viewshed analyses of the potential mountain height prior to its eruption and determined that one could indeed view the ocean if the mountain were at least 950 m higher than it is today. This aligns with the oral tradition, indicating that it may be over 2,400 years old, and plausibly in the range of 4,000 to 9,000 years old when the mountain may have been at such a height.

Uterine Arteriovenous Malformation: Diagnostic and Therapeutic Challenges

Uterine arteriovenous malformations are a rare cause of puerperal haemorrhage, but their incidence is increasing due to both improved diagnosis and the more frequent use of uterine surgery in recent years. The use of ultrasound, both B-mode and Doppler, is recommended for diagnosis and follow-up, as it has been shown to be the simplest and most cost-effective method. Endometrial thickening associated with an anechoic and vascular intramiometrial structure is very useful for diagnosis and can help to exclude other causes of dysfunctional bleeding. Pulsed Doppler shows low-resistance vessels and high pulsatility indices with a high peak systolic velocity (PSV). In a healthy myometrium, the vessels have a peak systolic velocity of 9–40 cm/s and a resistance index between 0.6 and 0.8, whereas in the case of AVMs, the systolic and diastolic velocities are 4–6 times higher (PSV 25–110 cm/s with a mean of 60 cm/s and a resistance index of 0.27–0.75 with a mean of 0.41). For treatment, we must individualise each case, taking into account haemodynamic stability, the patient’s reproductive wishes, and the severity of the AVM as assessed by its size and PSV.

Comprehensive dosimetric characterization of novel silicon carbide detectors with UHDR electron beams for FLASH radiotherapy.

The extremely fast delivery of doses with ultra high dose rate (UHDR) beams necessitates the investigation of novel approaches for real-time dosimetry and beam monitoring. This aspect is fundamental in the perspective of the clinical application of FLASH radiotherapy (FLASH-RT), as conventional dosimeters tend to saturate at such extreme dose rates. This study aims to experimentally characterize newly developed silicon carbide (SiC) detectors of various active volumes at UHDRs and systematically assesses their response to establish their suitability for dosimetry in FLASH-RT. SiC PiN junction detectors, recently realized and provided by STLab company, with different active areas (ranging from 4.5 to 10mm2) and thicknesses (10-20µm), were irradiated using 9MeV UHDR pulsed electron beams accelerated by the ElectronFLASH linac at the Centro Pisano for FLASH Radiotherapy (CPFR). The linearity of the SiC response as a function of the delivered dose per pulse (DPP), which in turn corresponds to a specific instantaneous dose rate, was studied under various experimental conditions by measuring the produced charge within the SiC active layer with an electrometer. Due to the extremely high peak currents, an external customized electronic RC circuit was built and used in conjunction with the electrometer to avoid saturation. The study revealed a linear response for the different SiC detectors employed up to 21Gy/pulse for SiC detectors with 4.5 mm2/10µm active area and thickness. These values correspond to a maximum instantaneous dose rate of 5.5 MGy/s and are indicative of the maximum achievable monitored DPP and instantaneous dose rate of the linac used during the measurements. The results clearly demonstrate that the developed devices exhibit a dose-rate independent response even under extreme instantaneous dose rates and dose per pulse values. A systematic study of the SiC response was also performed as a function of the applied voltage bias, demonstrating the reliability of these dosimeters with UHDR also without any applied voltage. This demonstrates the great potential of SiC detectors for accurate dosimetry in the context of FLASH-RT.

Studies on the Vascular Flora of Anaimudi and the Surrounding Regions, Kottayam District, Kerala

The paper deals with an account of the vegetation of Anaimudi (2,695 m) - the highest peak in the peninsular India - and the surrounding regions situated in the Kottayam District of Kerala. The above area has not received much attention in the detailed studies undertaken by various workers on the vegetation of the South Indian hill tops. Based on the explorations carried out by the authors during the years 1965-70, 317 taxa of vascular plants, under 233 genera and 101 families, are enumerated. An analysis of the distribution pattern of the shola and grassland species has shown that (1) the shola species are mainly of tropical stock, (2) quite a number of species on the shola fringes and the grassland are of temperate origin and (3) the temperate elements play a comparatively less important role in the composition of the vegetation at the higher altitudes (above 1,925 m), and that the predominent elements here are of tropical stock. The high incidence of endemic taxa in this region has been pointed out. Literature on the ecological status of the shola-grassland formation has been reviewed for a better understanding of the vegetation.

SYNTHESIS AND CHARACTERIZATION OF NANOSILICA (SiO2) VOLCANIC ROCK OF MOUNT BATUR IN BALI

This research was conducted to synthesize and characterize silica minerals (SiO2) from volcanic rocks in the active volcano in Bali, namely Mount Batur. The synthesis carried out on five different color variants of this rock sample is by the coprecipitation method which begins with the process of taking rock samples on Mount Batur, crushing the rock until it becomes powder with a size of 100 mesh, washing with distilled water and drying, immersing the rock powder in the solution. 2 M HCl for 12 hours, then the results of the soaking were reacted again with 7 M NaOH solution as a hydrolysis process to obtain pure SiO2 in the sample. In the form of sodium silicate precursor (Na2SiO3), the sample was titrated with a 2 M HCl solution to obtain silica gel which was then washed and dried until amorphous silica powder was produced. The results of the XRF analysis showed that the SiO2 mineral content in the sample after going through the synthesis process was 94.9% and the Si element was 89.9%. The XRD characterization results show that the phase formed from the sample has a quartz structure with the highest peak at an angle of 2θ = 23.07o, then decreases and levels out at an angle of 2θ = 32.94o which is characteristic of an amorphous structure and with a silica grain size of 8.47 nm – 8.65 nm.

Broadband and ascendant nonlinear optical properties of the wide bandgap material GaN nanowires

Gallium nitride (GaN) nanowire, as a type of wide bandgap nanomaterial, has attracted considerable interest because of its outstanding physicochemical properties and applications in energy storage and photoelectric devices. In this study, we prepared GaN nanowires via a facile chemical vapor deposition method and investigated their nonlinear absorption responses ranging from ultraviolet to near-infrared in the z-scan technology under irradiation by picosecond laser pulses. The experiment revealed that GaN nanowires exhibit remarkable nonlinear absorption characteristics attributed to their wide bandgap and nanostructure, including saturable absorption and reverse saturable absorption. When compared to bulk GaN crystals, the nanowires provide a richer and more potent set of nonlinear optical effects. Furthermore, we conducted an analysis of the corresponding electronic transition processes associated with photon absorption. Under high peak power density laser excitation, two-photon absorption or three-photon absorption dominate, with maximum modulation depths of 73.6%, 74.9%, 63.1% and 64.3% at 266 nm, 355 nm, 532 nm, and 1064 nm, respectively, corresponding to absorption coefficients of 0.22 cm/GW, 0.28 cm/GW, 0.08 cm/GW, and 2.82 ×10−4 cm3/GW2. At lower peak energy densities, GaN nanowires demonstrate rare and excellent saturation absorption characteristics at wavelength of 355 nm due to interband transitions, while saturable absorption is also observed at 532 nm and 1064 nm due to band tail absorption. The modulation depths are 85.2%, 41.9%, and 13.7% for 355 nm, 532 nm, and 1064 nm, corresponding to saturation intensities of 3.39 GW/cm2, 5.58 GW/cm2 and 14.13 GW/cm2. This indicates that GaN nanowires can be utilized as broadband optical limiters and high-performance pulse laser modulating devices, particularly for scarce ultraviolet optical limiters, and saturable absorbers for ultraviolet and visible lasers. Furthermore, our study demonstrates the application potential of wide bandgap nanomaterials in nonlinear optical devices.

Fine and dense bismuth electrocatalysts achieving high power density and cycling stability in vanadium flow batteries

Developing electrode materials that can work efficiently at high current densities while maintaining excellent stability is critical for reducing the unit cost of vanadium flow batteries (VFB). Herein, we report a Bi nanoparticles (∼10 nm) decorated thermal-active graphite felt (Bi@TGF) electrode fabricated through a simple polyvinylpyrrolidone guided approach. Fine and dense Bi electrocatalysts not only play an important role in catalyzing V2+/V3+ redox reaction, but also effectively suppress hydrogen evolution side reaction. As a result, the VFB assembled with Bi@TGF as negative electrode exhibits excellent rate performance (energy efficiency of 81.5 % at 200 mA cm−2) and extremely high peak power density (1023 mW cm−2 at 1250 mA cm−2). Moreover, Bi@TGF electrode demonstrates outstanding durability in 2500-cycle ultralong charge-discharge testing at 300 mA cm−2, with energy (voltage) efficiency retention rate of 99.2 % (98.9 %). The stable cycling ability of Bi@TGF under high operating current density endows its potential application in long-duration and high power density VFB.

Revolutionising pesticide detection: a high-sensitivity electrochemical sensor with CdS/g-C3N4/MWCNTs for paraquat monitoring

ABSTRACT Over a decade, the Malaysia National Poison Centre found that 40% of pesticide poisoning cases may be linked to excessive paraquat (PQ) in water, soil, or food, underscoring the widespread impact on public health and emphasising the importance of detecting even trace amounts of PQ residues in the environment. Thus, this study presents a novel electrochemical sensor based on multiwalled carbon nanotubes (MWCNTs) reinforced cadmium sulphide co-anchoring on graphitic carbon nitride (CdS/g-C3N4) nanocomposites for PQ detection. The CdS/g-C3N4 nanocomposite was successfully synthesised and characterised through FTIR, XRD, EDX, FESEM and TEM analysis. The modified electrode (CdS/g-C3N4/MWCNTs PE) exhibited improved electrocatalytic activity, as demonstrated by cyclic voltammetry (CV) and impedance spectroscopy. The CdS/g-C3N4/MWCNTs PE displayed a high CV peak and low Rct value which corresponded to a higher electron transfer rate, reduced charge transfer resistance and enhanced mass transport properties. The electrochemical sensor’s performance was evaluated for the detection of PQ, and it demonstrated a linear response in a range of 1.0 µM to 0.1 mM with a limit of detection of 0.14 μM. Furthermore, the sensor exhibited selectivity with a less than 16% potential interference from various organic chemicals and inorganic ions. The sensor’s applicability was tested by quantifying PQ in real water samples, showing excellent recovery percentages ranging from 98.9% to 102.0%. The developed electrochemical sensor provides a practical solution for the rapid and accurate monitoring of PQ levels in the environment. This work establishes the foundation for the development of a selective electrochemical sensor for pesticide analysis, addressing both public health and environmental concerns.

Atomically dispersed Iridium on Mo2C as an efficient and stable alkaline hydrogen oxidation reaction catalyst

Hydroxide exchange membrane fuel cells (HEMFCs) have the advantages of using cost-effective materials, but hindered by the sluggish anodic hydrogen oxidation reaction (HOR) kinetics. Here, we report an atomically dispersed Ir on Mo2C nanoparticles supported on carbon (IrSA-Mo2C/C) as highly active and stable HOR catalysts. The specific exchange current density of IrSA-Mo2C/C is 4.1 mA cm−2ECSA, which is 10 times that of Ir/C. Negligible decay is observed after 30,000-cycle accelerated stability test. Theoretical calculations suggest the high HOR activity is attributed to the unique Mo2C substrate, which makes the Ir sites with optimized H binding and also provides enhanced OH binding sites. By using a low loading (0.05 mgIr cm−2) of IrSA-Mo2C/C as anode, the fabricated HEMFC can deliver a high peak power density of 1.64 W cm−2. This work illustrates that atomically dispersed precious metal on carbides may be a promising strategy for high performance HEMFCs.

Comprehensive Two-Dimensional Liquid Chromatography-High-Resolution Mass Spectrometry for Complex Protein Digest Analysis Using Parallel Gradients.

Despite the high gain in peak capacity, online comprehensive two-dimensional liquid chromatography coupled with high-resolution mass spectrometry (LC × LC-HRMS) has not yet been widely applied to the analysis of complex protein digests. One reason is the method's reduced sensitivity which can be linked to the high flow rates of the second separation dimension (2D). This results in higher dilution factors and the need for flow splitters to couple to ESI-MS. This study reports proof-of-principle results of the development of an RPLC × RPLC-HRMS method using parallel gradients (2D flow rate of 0.7 mL min-1) and its comparison to shifted gradient methods (2D of 1.4 mL min-1) for the analysis of complex digests using HRMS (QExactive-Plus MS). Shifted and parallel gradients resulted in high surface coverage (SC) and effective peak capacity (SC of 0.6226 and 0.7439 and effective peak capacity of 779 and 757 in 60 min). When applied to a cell line digest sample, parallel gradients allowed higher sensitivity (e.g., average MS intensity increased by a factor of 3), allowing for a higher number of identifications (e.g., about 2600 vs 3900 peptides). In addition, reducing the modulation time to 10 s significantly increased the number of MS/MS events that could be performed. When compared to a 1D-RPLC method, parallel RPLC × RPLC-HRMS methods offered a higher separation performance (FHWH from 0.12 to 0.018 min) with limited sensitivity losses resulting in an increase of analyte identifications (e.g., about 6000 vs 7000 peptides and 1500 vs 1990 proteins).

Mechanisms of formation and shape control of pentagonal Pd-nanostars and their unique properties in electrocatalytic methanol oxidation and membrane separation of high-purity hydrogen

Membranes on palladium alloy basis with surface modified by nanoparticles with high catalytic activity are useful in deep hydrogen purification and single-stage process of high-purity hydrogen production. This paper reports the development and improvement of methods for synthesis of Pd-based pentatwinned nanoparticles of strictly specified morphology with certain shapes, facets and composition. The competing effect of surfactants and optimization of the halide ions ratio in solution make it possible to direct a particle growth towards formation of pentatwinned Pd-nanostars. Pd–23%Ag coatings synthesized on the surface showed uniquely high peak current density of up to 238 mA cm−2 in alkaline methanol oxidation reaction. This is due to both increased surface area and greater catalytic activity of nanostars’ facets. A record increase in hydrogen permeability of up to 12.5 mmol s−1 m−2 at 100 °C has been achieved for palladium-silver membranes with modified surface. This indicates an acceleration of sorption/desorption stages. The developed method for controlling morphology of nanoscale coatings opens the way to the production of membrane hydrogen filters, which operate at room temperature.

Novel biaryloxazolidinone derivatives with broad-spectrum antibacterial activity, favorable drug-like profiles and in vivo efficacy against linezolid-resistant Staphylococcusaureus

The emergence of multidrug-resistant bacteria along with a declining pipeline of clinically useful antibiotics has led to the urgent need for the development of more effective antibacterial agents to treat drug-resistant bacteria. We previously discovered compound OB-158 with potent antibacterial activity but exhibited poor oral bioavailability. Herein, a systematic structural optimization of OB-158 to improve pharmacokinetic profiles yielded 26 novel biaryloxazolidinone analogues, and their activities against Gram-positive S. aureus, multidrug resistant S. aureus and Enterococcus faecalis were evaluated. Remarkably, compound 8b was identified with potent antibacterial activity against S. aureus (MIC=0.06μg/mL), MSSA (MIC=0.125μg/mL), MRSA (MIC=0.06μg/mL), LRSA (MIC=0.125μg/mL) and LREFa (MIC=0.5μg/mL). Compound 8b was demonstrated as a promising candidate through druglikeness evaluation including metabolism in microsomes and plasma, Caco-2cell permeability, plasma protein binding, cytotoxicity, and inhibition of CYP450 and human monoamine oxidase. Notably, compound 8b displayed excellent PK profile with appropriate T1/2 of 1.49h, high peak plasma concentration (Cmax=2320ng/mL), high plasma exposure (AUC0-t=8310hng/mL), and superior oral bioavailability (F=68.1%) in Sprague-Dawley rats. Ultimately, in vivo efficacy of compound 8b in a mouse model of LRSA systemic infection was also demonstrated. Taken together, compound 8b represents a promising drug candidate for the treatment of linezolid-resistant Gram-positive bacterial strains infection.

A retrospective study on whelping seasonality of the Cirneco dell'Etna dog in Sicily, Italy.

Previous to this study, there is no data relating to the reproductive physiology of the Cirneco dell'Etna breed. The birth date of 141 bitches and 104 sires registered at the National Agency of the Italian Kennel Club (ENCI) from all Sicilian breeders, and data related their fertile matings, which produced 266 whelps over a 14-year period, (2009-2022) were collected. Total whelping produced 1069 pups. The mean bitch age at first whelping was 39.13 ± 21.7 months and the mean litter size was 3.84 ± 2.08. The birth period of the bitches and sires was significantly influenced by the month of the year (p < 0.01), as was the distribution of the first (p < 0.05) and subsequent whelping periods (p < 0.01). Whelping distributions show a significant difference between the highest peak in April (which roughly corresponds to a period of heat in February) and in July (which roughly corresponds to a period of heat in May) and the lowest peak in March. No influence of month on litter size and sex ratio was found. Available data suggests that some ancient breeds such as the Cirneco dell'Etna may show seasonal patterns as a vestige of the stricter seasonality of its closest relative the wolf.

Influence of HiPIMS Pulse Widths on the Structure and Properties of Copper Films.

High-power pulse magnetron sputtering is a new type of magnetron sputtering technology that has advantages such as high peak power density and a high ionization rate compared to DC magnetron sputtering. In this paper, we report the effects of different pulse widths on the current waveform and plasma spectrum of target material sputtering, as well as the structure and properties of Cu films prepared under the same sputtering voltage and duty cycle. Extending the pulse width can make the sputtering enter the self-sputtering (SS) stage and improve the ion quantity of sputtered particles. The Cu film prepared by HiPIMS with long pulse width has higher bond strength and lower electrical resistivity compared to the Cu film prepared by short pulse width. In terms of microstructure, the Cu film prepared by HiPIMS with the long pulse width has a larger grain size and lower micro-surface roughness. When the pulse width is bigger than 200 μs, the microstructure of the Cu film changes from granular to branched. This transformation reduces the interface on the Cu film, further reducing the resistivity of the Cu film. Compared to short pulses, long pulse width HiPIMS can obtain higher quality Cu films. This result provides a new process approach for preparing high-quality Cu films using HiPIMS technology.

Multi-Source Collaborative Control Technology of Photovoltaic Power Generation Based on Differential Evolution-Gray Wolf Optimization Algorithm

The existing photovoltaic power generation multi-source collaborative control technology cannot improve the control effect of microgrid, resulting in high peak load balancing cost of microgrid. Therefore, the photovoltaic power generation multi-source collaborative control technology based on differential evolution (DE)-gray wolf optimization (GWO) algorithm is adopted. The main components of the microgrid system, such as photovoltaic power generation equipment, hydroelectric power generation equipment, and battery pack, are modeled. With the goal of minimum peak cost and maximum transmission power, collaborative control of water, light and energy storage is carried out. The gray Wolf algorithm is used to solve the multi-objective problem of water and light storage in microgrid, and the gray Wolf algorithm is optimized by DE algorithm. Experiments show that the convergence speed of the optimized DEVOLU-Gray Wolf algorithm is obviously accelerated, and the problem of falling into the local optimal solution is completely avoided. After the application of this method, the photovoltaic, hydraulic, and battery of the microgrid run in order, ensure the smooth operation of the microgrid, and improve the economic benefit of the microgrid.

A promising strontium and cobalt-free Ba1-xCaxFeO3-δ air electrode for reversible protonic ceramic cells

The air electrode with strontium and cobalt elements has the elemental diffusion or delamination issue on the air electrode/electrolyte interface in reversible protonic ceramic cells (RPCCs). Hence the development of strontium and cobalt-free triple conducting (H+/O2-/e-) air electrodes with high electrochemical activity and stability is urgent. Here, we report a strontium and cobalt-free Ba0.8Ca0.2FeO3-δ (BCF82) air electrode with high catalytic activity and electrochemical stability for oxygen reduction/evolution reactions. A RPCC with the BCF82 air electrode shows a high peak power density of 1.14 W cm−2 in the fuel cell mode and a current density of 3.49 A cm−2 under 1.3 V in the electrolysis mode at 700 °C. Furthermore, the cell demonstrates suitable stability in the fuel cell, electrolysis and reversible modes at 600 °C for hundreds of hours without elemental segregation and delamination issue. This work offers an efficient approach to develop low-cost and durable air electrodes for RPCCs.