Transcriptomics integrated with metabolomics reveals the mechanism of CaCl_(2)-HCl electrolyzed water-induced glucosinolate biosynthesis in broccoli sprouts

Glucosinolates are important phytochemicals in Brassicaceae.We investigated the effect of CaCl_(2)-HCl electrolyzed water(CHEW)on glucosinolates biosynthesis in broccoli sprouts.The results showed that CHEW treatment significantly decreased reactive oxygen species(ROS)and malondialdeh yde(MDA)contents in broccoli sprouts.On the the 8^(th)day,compared to tap water treatment,the the total glucosinolate content of broccoli sprouts with CHEW treatment increased by 10.6%and calcium content was dramatically enhanced from 14.4 mg/g DW to 22.7 mg/g DW.Comparative transcriptome and metabolome analyses revealed that CHEW treatment activated ROS and calcium signaling transduction pathways in broccoli sprouts and they interacted through MAPK cascades.Besides,CHEW treatment not only promoted the biosynthesis of amino acids,but also enhanced the expression of structural genes in glucosinolate synthesis through transcription factors(MYBs,bHLHs,WRKYs,etc.).The results of this study provided new insights into the regulatory network of glucosinolates biosynthesis in broccoli sprouts under CHEW treatment.

Effect of Alkaline Electrolyzed Water on Performance Improvement of Green Concrete with High Volume of Mineral Admixtures

The strength and durability of concrete will be significantly reduced at high volume of mineral admixture,and the poor early strength of concrete also still needs to be solved.In this investigation,a highly active alkaline electrolyzed waters was used as mixing water to improve the early strength and enhance the durability of green concrete with high volume mineral admixture,the influences of alkaline electrolyzed water(AEW)on hydration activity of mineral admixture and durability of concrete were determined.The results showed that compared with natural tap water,AEW can accelerate early hydration process of cement in concrete and produce comparatively more hydrated products,leading to a 13.6%higher compressive strength than that of ordinary concrete at early age,but the improvement effect of AEW concrete was relatively reduced at long-term age.Meanwhile,the activity of mineral admixtures could be stimulated by AEW to some extent,the strength and durability performance of AEW concrete after double doping 25%slag and 25%fly ash can still reach the level of ordinary cement concrete without mineral admixtures.The SEM micromorphology of 7 d hydrated natural tap water cement paste was observed to be flaky and tabular,but the AEW cement pastes present obvious cluster and granulation phenomenon.The SEM microstructure of AEW concrete with mineral admixtures is more developed and denser than ordinary tap water concrete with mineral admixtures.Therefore,the AEW probably could realize the effective utilization of about 50%mineral admixture amount of concrete without strength loss,the cement production cost and associated CO_(2) emission reduced,which has a good economic and environmental benefit.

Electrolyzed Oxidized Water (EOW): Non-Thermal Approach for Decontamination of Food Borne Microorganisms in Food Industry

Electrolyzed Oxidized Water (EOW) is produced by passing a diluted salt solution through an electrolytic cell, having anode and cathode electrodes. The anode and cathode are separated by a bipolar membrane. Negatively charged ions—chloride and hydroxide in the diluted salt solution move to anode to give up electrons and become gas (O2, Cl2) and hypochlorous acid and having redox potential of +700 to +800 mV with pH 4.0. It has a strong oxidation potential and a shortage of electrons giving it the ability to oxidize and sterilize. In microbial inactivation process, oxidized water damage cell membranes, create disruption in cell metabolic processes and essentially kill the cell. EOW, also a strong acid, is different to hydrochloric acid or sulfuric acid in that it is not corrosive to skin, mucous membrane, or organic material. It is easy to handle and suitable for the sanitation of the plant and decontamination of foods. Electrolyzed water has been tested and used as a disinfectant in the food industry and other applications.

Effects of high-pressure activated slightly acidic electrolyzed water on cleaning and sterilization of pig transfer vehicles

The establishment of biosafety system is of enormous importance to the livestock and poultry production in terms of mitigating the transmission of diseases and implementing regional prevention and control measures.However,the current sterilization technology presents several drawbacks,including time-consuming procedures,chemical residues,and challenges in treating the sewage after rinsing.In this study,a novel cleaning and sterilization method that combines slightly acidic electrolyzed water and high pressure water-jet was developed.An orthogonal test was conducted to examine the correlation between high-pressure conditions and the various non-structural parameters on the efficacy of sterilization rate.In a field test,the effectiveness of the technology in cleaning pig transfer vehicles was evaluated by the total plate count and variations of community composition.The findings revealed that the combination of process parameters,including an available chlorine concentration of 200 mg/L,rinsing pressure of 170 bar,rinsing duration of 10 s,and residence time of 15 min,resulted in a removal rate of colony concentration on the surface of pig transfer vehicles of(96.50±0.91)%.Moreover,it was demonstrated to effectively inhibit a variety of pathogenic bacteria.The innovative cleaning system has the potential to replace traditional methods and reduces pollution while saving time and labor.It introduces a novel approach for sterilization of transportation in livestock and poultry farms as well as the biosafety construction of the animal husbandry.

Electrolyzed water and its application in animal houses

Electrolyzed water(EW) can be produced by electrolysis of a dilute salt solution. Slightly acidic electrolyzed water(SAEW, p H 5.0–6.5) and neutral electrolyzed water(NEW, p H 6.5–8.5) are considered healthy and environmentally friendly because no hazardous chemicals are added in its production, there is reduced corrosion of surfaces and it minimizes the potential for damage to animal and human health. Over the last decade, EW has become increasingly popular as an alternative disinfectant for decontamination in animal houses. However, there have been some issues related to EW that are not well known, including different mechanisms for generation of SAEW and NEW, and the antimicrobial mechanism of EW. This review covers the definitions of SAEW and NEW, different generation systems for SAEW and NEW, the antimicrobial mechanism of EW, and recent developments related to the application of SAEW and NEW in animal houses.

Preservative effects of the combined treatment of slightly acidic electrolyzed water and ice on pomfret

This study assessed the combined effect of slightly acidic electrolyzed water(SAEW)and slightly acidic electrolyzed water ice(SAEW-ice)on the quality of pomfrets over a period of 18 d of cold storage at 4°C.A presoak for 5 min in SAEW solution(22 mg/L)was used before the pomfrets were placed on SAEW-ice(pH:6.45;ORP:803 mV;ACC:18 mg/L);The changes in physicochemical properties(i.e.,pH,thiobarbituric acid,total volatile basic nitrogen and texture profile),microbial loads and sensory characteristics were all analyzed.Compared with the tap water(TW)group,the total bacterial counts of the SAEW group significantly decreased by 1.27 log10 CFU/g after immersion(p<0.05).The shelf life of the pomfrets was prolonged by 9 d by the combined treatment of SAEW and SAEW-ice during storage at 4℃.On the 18th day,the gumminess and chewiness values of the pomfrets in the SAEW+SAEW-ice group were 195 g and 3.97 mJ,respectively,which were significantly higher than those of the other groups(p<0.05).The results suggested that SAEW+SAEW-ice treatments have great potential as a novel method to maintain the quality and extend the shelf life of pomfrets during refrigerated storage.

Inactivation efficiency of slightly acidic electrolyzed water against microbes on facility surfaces in a disinfection channel

Slightly acidic electrolyzed water(SAEW,pH 6.0-6.5)is an ideal and environmentally-friendly disinfectant,which was used to prevent and control bacterial infections on farms.This work aims to investigate the inactivation effectiveness of SAEW in inactivating microbes in a disinfection channel.The bactericidal efficiency of SAEW on equipment surfaces was compared to two commercial disinfectants,Kuei A bromide solution(KAS,5:1000 v/v)and Glutaraldehyde solution(GS,5:1000 v/v).The disinfection effectiveness of SAEW in inactivating Salmonella enteritidis(S.enteritidis)on equipment surfaces in the disinfection channel was evaluated,and a model was developed using multiple linear regression analysis.Results indicated that SAEW was significantly(p<0.05)more efficient than KAS and GS on kits and clothing in the disinfection channel at 1 min.The SAEW did not contribute as aggressively to respiratory difficulty as KAS and GS.Maximum reductions of 2.362 log10 CFU/cm^(2),2.613 log10 CFU/cm^(2) and 2.359 log10 CFU/cm^(2) for Salmonella enteritidis were obtained from clothing surfaces,iron materials,and kits treated with SAEW for 2.5 min at a chlorine concentration of 220 mg/L.Moreover,the established model had a good fit-quantified by the determination coefficient R^(2)(0.939)and a lack of fit test(p>0.05).In addition,available chlorine concentration(ACC)was an important factor than other factors,and the inactivation efficiency of Salmonella enteritidis sprayed by SAEW treatment was different between iron materials,kits and clothing surfaces(iron>kit>clothing).

Effect of electrolyzed oxidizing water and hydrocolloid occlusive dressings on excised burn-wounds in rats

Objective: To study the efficacy of electrolyzed oxidizing water ( EOW ) and hydrocolloid occlusive dressings in the acceleration of epithelialization in excised burn-wounds in rats.Methods: Each of the anesthetized Sprague-Dawley rats (n = 28) was subjected to a third-degree burn that covered approximately 10% of the total body surface area. Rats were assigned into four groups: Group Ⅰ ( no irrigation), Group Ⅱ (irrigation with physiologic saline), Group Ⅲ ( irrigation with EOW ) and Group Ⅳ ( hydrocolloid occlusive dressing after EOW irrigation). Wounds were observed macroscopically until complete epithelialization was present, then the epithelialized wounds were examined microscopically. Results: Healing of the burn wounds was the fastest in Group Ⅳ treated with hydrocolloid occlusive dressing together with EOW. Although extensive regenerative epidermis was seen in each Group, the proliferations of lymphocytes and macrophages associated with dense collagen deposition were more extensive in Group Ⅱ, Ⅲ and IV than in Group Ⅰ. These findings were particularly evident in Group Ⅲ and Ⅳ.Conclusions: Wound Healing may be accelerated by applying a hydrocolloid occlusive dressing on burn surfaces after they are cleaned with EOW.

Relevance of cathepsins activity and texture in slightly acidic electrolyzed water-slurry iced mackerel(Pneumatophorus japonicus)

The incorporation of SAEW and SI can effectively maintain the characteristics of texture in marine fish.This study aimed to investigate the relevance of cathepsin activity for texture and the establishment of a shelf-life model of mackerel(Pneumatophorus japonicus)stored at 4◦C.Before the cold storage,mackerel samples were exposed to flake ice(Control),slurry ice(SI),and slightly acidic electrolyzed water-slurry ice(SAEW-SI),respectively.Then the TVC,K-value,cathepsin activity,texture,and sensory attributes were investigated.The results showed that the TVC and K-value of samples in SAEW-SI group was significantly lower by approximately 1 log CFU/g and 17%than those in Control group(P<0.05).Meanwhile,there was a tendency to first increase and then decrease on the activities of cathepsin B,D and L.Results of texture profile analysis(TPA)clarified that SAEW-SI can markedly suppress the decrease of hardness,springiness and chewiness(P<0.05).During the experimental period,the highest sensory scores were obtained in SAEW-SI group.In addition,the heat map of correlation analysis suggested that texture attributes(hardness)were negatively correlated with cathepsin B(r=-0.66),cathepsin D(r=-0.49),and cathepsin L(r=-0.69),respectively.According to the principal component analysis(PCA)and analysis of linear regression,SAEW-SI treatment could effectively maintain mackerel quality and extend the estimated shelf-life of mackerel by at least 5 days compared to Control group.Therefore,SAEW-SI could be suggested as a novel strategy for cold-chain transportation in seafood industry.

Boosting Oxygen Evolution Reaction Performance on NiFe‑Based Catalysts Through d‑Orbital Hybridization

Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based catalysts.By introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in AEMWEs.Herein,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this work.Experimental and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER performance.More critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.

Disinfection effect of adding slightly acidic electrolyzed water to artificial seawater under the condition of static hybrid

Mixed solution of slightly acidic electrolyzed water(SAEW)and artificial seawater was used to investigate the disinfection potential of SAEW in artificial seawater.Inoculated Vibrio parahaemolyticus(suspended in 3%sodium chloride alkaline peptone water and 0.85%sodium chloride water,respectively)was subjected to different mixed-SAEW and SAEW immersion treatments(5-20 mg/L available chlorine concentration(ACC)).In the presence of organic matter,4.07 logCFU/mL significant reduction(p<0.05)was achieved after treating with 20 mg/L mixed-SAEW for 15 min.There was 5.13 logCFU/mL reduction after treating with 15 mg/L SAEW for 15 min.For V.parahaemolyticus suspended in 0.85%sodium chloride solution,it was undetected after 30 s SAEW treatment(5 mg/L ACC)or 120 s mixed-SAEW treatment(10 mg/L ACC).At a ratio of SAEW and artificial seawater at 1:15(V/V),SAEW could inactivate V.parahaemolyticus to undetectable level in artificial seawater in one minute,which was comparable with UV treatment of 10 W.The results indicated high sanitization potential of SAEW against V.parahaemolyticus in aquaculture seawater.

The increase of antioxidant capacity of broccoli sprouts subject to slightly acidic electrolyzed water

The growing recognition of a healthy lifestyle framework has promoted the development of novel functional foods or superfoods with abundant nutrients and health-promoting properties.Therefore,the influence of slightly acidic electrolyzed water(SAEW)as an elicitor on broccoli sprouts was investigated.The increase of electrolyte leakage percentage,thiobarbituric acid reactive substances levels and proline concentration indicated that the defense system of broccoli sprouts had responded to stress caused by SAEW.Furthermore,the antioxidant enzymes and secondary metabolites,phenolic compounds,were evaluated and revealed the enhancement of antioxidant enzymes(superoxide dismutase,peroxidases,catalase,and ascorbate peroxidase)activities and phenolic compounds content in broccoli sprouts with SAEW treatment.The major groups of phenolic composition in broccoli sprouts were phenolic acids and flavonoids.The Folin-Ciocalteu index and antioxidant activity assay also proved the enhancement of antioxidant capacity of broccoli sprouts with SAEW treatment.Results from this study indicated that SAEW treatment could increase the antioxidant ability of broccoli sprouts.

Bactericidal efficacy of slightly acidic electrolyzed water(SAEW)against Listeria monocytogenes planktonic cells and biofilm on food-contact surfaces

In the present study,the bactericidal efficacy of slightly acidic electrolyzed water(SAEW)against Listeria monocytogenes(L.monocytogenes)planktonic cells and biofilm on food-contact surfaces including stainless steel and glass was systematically evaluated.The results showed that SAEW(pH 5.09 and available chlorine concentration(ACC)of 60.33 mg/L)could kill L.monocytogenes on food-contact surfaces completely in 30 s,a disinfection efficacy equal to that of NaCIO solutions(pH 9.23 and ACC of 253.53 mg/L).The results showed that long exposure time and high ACC contributed to the enhancement of the disinfection efficacy of SAEW on L.monocytogenes on food-contact surfaces.Moreover,the log reduction of SAEW treatment presented an increasing tendency within the prolonging of treatment time when SAEW was used to remove the L.monocytogenes bioflm formed on stainless steel and glass surfaces,which suggested that SAEW could remove L.monocytogenes bio-film effectively and its disinfection efficacy is equal to(in the case of stainless steel)or higher than(in the case of glass)that of high-ACC NaCIO solutions.In addition,the results of the crystal violet staining and scanning electron microscopy also demonstrated that SAEW treatment could remove the L.monocytogenes biofilm on food-contact surfaces.

Effect of bipolar-plates design on corrosion,mass and heat transfer in proton-exchange membrane fuel cells and water electrolyzers:A review

Attaining a decarbonized and sustainable energy system,which is the core solution to global energy issues,is accessible through the development of hydrogen energy.Proton-exchange membrane water electrolyzers(PEMWEs)are promising devices for hydrogen production,given their high efficiency,rapid responsiveness,and compactness.Bipolar plates account for a relatively high percentage of the total cost and weight compared with other components of PEMWEs.Thus,optimization of their design may accelerate the promotion of PEMWEs.This paper reviews the advances in materials and flow-field design for bipolar plates.First,the working conditions of proton-exchange membrane fuel cells(PEMFCs)and PEMWEs are compared,including reaction direction,operating temperature,pressure,input/output,and potential.Then,the current research status of bipolar-plate substrates and surface coatings is summarized,and some typical channel-rib flow fields and porous flow fields are presented.Furthermore,the effects of materials on mass and heat transfer and the possibility of reducing corrosion by improving the flow field structure are explored.Finally,this review discusses the potential directions of the development of bipolar-plate design,including material fabrication,flow-field geometry optimization using threedimensional printing,and surface-coating composition optimization based on computational materials science.

Electrocatalytic CO_(2)reduction to syngas

While carbon dioxide(CO_(2))is a major greenhouse gas,it is also an important C1 resource.In the trend of energy conservation and emission reduction,electrocatalytic reduction has become a very promising strategy for CO_(2)utilization because it can convert CO_(2)directly to high-valued chemicals and fuels under mild conditions.In particular,the product CO and by-product H_(2)can be combined into syngas by an electrocatalytic CO_(2)reduction reaction(CO_(2)RR)in an aqueous medium.Different molar ratios of CO and H_(2)may be used to produce essential bulk chemicals or liquid fuels such as methanol,alkanes,and olefins through thermochemical catalysis,Fischer-Tropsch synthesis,microbial fermentation,and other techniques.This work discusses the latest strategies in controlling the molar ratio of CO/H_(2)and improving the yield of CO_(2)RR-to-syngas.The challenges of electrocatalytic syngas production are analyzed from an industrial application perspective,and the possible measures to overcome them are proposed in terms of new catalyst design,electrolyte innovation,flow reactor optimization,anodic reaction coupling,and operando technique application.

Trifunctional robust electrocatalysts based on 3D Fe/N-doped carbon nanocubes encapsulating Co4N nanoparticles for efficient battery-powered water electrolyzers

Herein,we have designed a highly active and robust trifunctional electrocatalyst derived from Prussian blue analogs,where Co_(4)N nanoparticles are encapsulated by Fe embedded in N-doped carbon nanocubes to synthesize hierarchically structured Co_(4)N@Fe/N-C for rechargeable zinc-air batteries and overall water-splitting electrolyzers.As confirmed by theoretical and experimental results,the high intrinsic oxygen reduction reaction,oxygen evolution reaction,and hydrogen evolution reaction activities of Co_(4)N@Fe/N-C were attributed to the formation of the heterointerface and the modulated local electronic structure.Moreover,Co_(4)N@Fe/N-C induced improvement in these trifunctional electrocatalytic activities owing to the hierarchical hollow nanocube structure,uniform distribution of Co_(4)N,and conductive encapsulation by Fe/N-C.Thus,the rechargeable zinc-air battery with Co_(4)N@Fe/N-C delivers a high specific capacity of 789.9 mAh g^(-1) and stable voltage profiles over 500 cycles.Furthermore,the overall water electrolyzer with Co_(4)N@Fe/N-C achieved better durability and rate performance than that with the Pt/C and IrO2 catalysts,delivering a high Faradaic efficiency of 96.4%.Along with the great potential of the integrated water electrolyzer powered by a zinc-air battery for practical applications,therefore,the mechanistic understanding and active site identification provide valuable insights into the rational design of advanced multifunctional electrocatalysts for energy storage and conversion.

A Cu-Pd alloy catalyst with partial phase separation for the electrochemical CO_(2) reduction reaction

Cu catalysts can convert CO_(2) through an electrochemical reduction reaction into a variety of useful carbon-based products.However,this capability provides an obstacle to increasing the selectivity for a single product.Herein,we report a simple fabrication method for a Cu-Pd alloy catalyst for use in a membrane electrode assembly(MEA)-based CO_(2) electrolyzer for the electrochemical CO_(2) reduction reaction(ECRR)with high selectivity for CO production.When the composition of the Cu-Pd alloy catalyst was fabricated at 6:4,the selectivity for CO increased and the production of multi-carbon compounds and hydrogen is suppressed.Introducing a Cu-Pd alloy catalyst with 6:4 ratio as the cathode of the MEAbased CO_(2) electrolyzer showed a CO faradaic efficiency of 92.8%at 2.4 V_(cell).We assumed that these results contributed from the crystal planes on the surface of the Cu-Pd alloy.The phases of the Cu-Pd alloy catalyst were partially separated through annealing to fabricate a catalyst with high selectivity for CO at low voltage and C_(2)H_4 at high voltage.The results of CO-stripping testing confirmed that when Cu partially separates from the lattice of the Cu-Pd alloy,the desorption of~*CO is suppressed,suggesting that C-C coupling reaction is favored.

Pulsed laser interference patterning of transition-metal carbides for stable alkaline water electrolysis kinetics

We investigated the role of metal atomization and solvent decomposition into reductive species and carbon clusters in the phase formation of transition-metal carbides(TMCs;namely,Co_(3)C,Fe_(3)C,TiC,and MoC)by pulsed laser ablation of Co,Fe,Ti,and Mo metals in acetone.The interaction between carbon s-p-orbitals and metal d-orbitals causes a redistribution of valence structure through charge transfer,leading to the formation of surface defects as observed by X-ray photoelectron spectroscopy.These defects influence the evolved TMCs,making them effective for hydrogen and oxygen evolution reactions(HER and OER)in an alkaline medium.Co_(3)C with more oxygen affinity promoted CoO(OH)intermediates,and the electrochemical surface oxidation to Co_(3)O_(4)was captured via in situ/operando electrochemical Raman probes,increasing the number of active sites for OER activity.MoC with more d-vacancies exhibits strong hydrogen binding,promoting HER kinetics,whereas Fe_(3)C and TiC with more defect states to trap charge carriers may hinder both OER and HER activities.The results show that the assembled membrane-less electrolyzer with Co_(3)C∥Co_(3)C and MoC∥MoC electrodes requires~2.01 and 1.99 V,respectively,to deliver a 10 mA cm−2 with excellent electrochemical and structural stability.In addition,the ascertained pulsed laser synthesis mechanism and unit-cell packing relations will open up sustainable pathways for obtaining highly stable electrocatalysts for electrolyzers.

Towards high-performance and robust anion exchange membranes(AEMs)for water electrolysis:Super-acid-catalyzed synthesis of AEMs

The increasing demand for hydrogen energy to address environmental issues and achieve carbon neutrality has elevated interest in green hydrogen production,which does not rely on fossil fuels.Among various hydrogen production technologies,anion exchange membrane water electrolyzer(AEMWE)has emerged as a next-generation technology known for its high hydrogen production efficiency and its ability to use non-metal catalysts.However,this technology faces significant challenges,particularly in terms of the membrane durability and low ionic conductivity.To address these challenges,research efforts have focused on developing membranes with a new backbone structure and anion exchange groups to enhance durability and ionic conductivity.Notably,the super-acid-catalyzed condensation(SACC)synthesis method stands out due to its user convenience,the ability to create high molecular weight(MW)polymers,and the use of oxygen-tolerant organic catalysts.Although the synthesis of anion exchange membranes(AEMs)using the SACC method began in 2015,and despite growing interest in this synthesis approach,there remains a scarcity of review papers focusing on AEMs synthesized using the SACC method.The review covers the basics of SACC synthesis,presents various polymers synthesized using this method,and summarizes the development of these polymers,particularly their building blocks including aryl,ketone,and anion exchange groups.We systematically describe the effects of changes in the molecular structure of each polymer component,conducted by various research groups,on the mechanical properties,conductivity,and operational stability of the membrane.This review will provide insights into the development of AEMs with superior performance and operational stability suitable for water electrolysis applications.

Generation of input spectrum for electrolysis stack degradation test applied to wind power PEM hydrogen production

Hydrogen production by proton exchange membrane electrolysis has good fluctuation adaptability,making it suitable for hydrogen production by electrolysis in fluctuating power sources such as wind power.However,current research on the durability of proton exchange membrane electrolyzers is insufficient.Studying the typical operating conditions of wind power electrolysis for hydrogen production can provide boundary conditions for performance and degradation tests of electrolysis stacks.In this study,the operating condition spectrum of an electrolysis stack degradation test cycle was proposed.Based on the rate of change of the wind farm output power and the time-averaged peak-valley difference,a fluctuation output power sample set was formed.The characteristic quantities that played an important role in the degradation of the electrolysis stack were selected.Dimensionality reduction of the operating data was performed using principal component analysis.Clustering analysis of the data segments was completed using an improved Gaussian mixture clustering algorithm.Taking the annual output power data of wind farms in Northwest China with a sampling rate of 1 min as an example,the cyclic operating condition spectrum of the proton-exchange membrane electrolysis stack degradation test was constructed.After preliminary simulation analysis,the typical operating condition proposed in this paper effectively reflects the impact of the original curve on the performance degradation of the electrolysis stack.This study provides a method for evaluating the degradation characteristics and system efficiency of an electrolysis stack due to fluctuations in renewable energy.