The Mg–12Gd–1Er–1Zn–0.9 Zr(wt%)alloy with ultra-high strength and ductility was developed via hot extrusion combined with pre-deformation and two-stage aging treatment.The age-hardening behavior and microstructure...The Mg–12Gd–1Er–1Zn–0.9 Zr(wt%)alloy with ultra-high strength and ductility was developed via hot extrusion combined with pre-deformation and two-stage aging treatment.The age-hardening behavior and microstructure evolution were investigated.Pre-deformation introduced a large number of dislocations,resulting in strain hardening and higher precipitation strengthening in the subsequent two-stage aging.As a result,the alloy showed a superior strength–ductility balance with a yield strength of 506 MPa,an ultimate tensile strength of 549 MPa and an elongation of 8.2%at room temperature.The finer and denserβ’precipitates significantly enhanced the strength,and the bimodal structure,smallβ-Mg5RE phase as well as denseγ’precipitates ensured the good ductility of the alloy.It is suggested that the combination of pre-deformation and two-stage aging treatment is an eff ective method to further improve the mechanical properties of wrought Mg alloys.展开更多
The effect of two-stage aging on the microstructures and superplasticity of 01420 Al-Li alloy was investigated by means of OM, TEM analysis and stretching experiment. The results demonstrate that the second phase part...The effect of two-stage aging on the microstructures and superplasticity of 01420 Al-Li alloy was investigated by means of OM, TEM analysis and stretching experiment. The results demonstrate that the second phase particles distributed more uniformly with a larger volume fraction can be observed after the two-stage aging (120℃, 12 h+300℃, 36 h) compared with the single-aging(300℃, 48 h). After rolling and recrystallization annealing, fine grains with size of 8-10 urn are obtained, and the superplastic elongation of the specimens reaches 560% at strain rate of 8×10-4s-1 and 480℃. Uniformly distributed fine particles precipitate both on grain boundaries and in grains at lower temperature. When the sheet is aged at high temperature, the particles become coarser with a large volume fraction.展开更多
A new unified constitutive model was developed to predict the two-stage creep-aging(TSCA)behavior of Al-Zn-Mg-Cu alloys.The particular bimodal precipitation feature was analyzed and modeled by considering the primary ...A new unified constitutive model was developed to predict the two-stage creep-aging(TSCA)behavior of Al-Zn-Mg-Cu alloys.The particular bimodal precipitation feature was analyzed and modeled by considering the primary micro-variables evolution at different temperatures and their interaction.The dislocation density was incorporated into the model to capture the effect of creep deformation on precipitation.Quantitative transmission electron microscopy and experimental data obtained from a previous study were used to calibrate the model.Subsequently,the developed constitutive model was implemented in the finite element(FE)software ABAQUS via the user subroutines for TSCA process simulation and the springback prediction of an integral panel.A TSCA test was performed.The result shows that the maximum radius deviation between the formed plate and the simulation results is less than 0.4 mm,thus validating the effectiveness of the developed constitutive model and FE model.展开更多
SKI family transcriptional corepressor 1(SKOR1also known as LbxCor1, Fussel15, or CORL1), is a member of the SKI family of proteins and is transcribed from a protein-coding gene located on chromosome 15 in humans, tha...SKI family transcriptional corepressor 1(SKOR1also known as LbxCor1, Fussel15, or CORL1), is a member of the SKI family of proteins and is transcribed from a protein-coding gene located on chromosome 15 in humans, that has a molecular weight of approximately 100 kDa. Skor1 is highly expressed in neurons in the central nervous system of both humans and rodents.展开更多
In modern ZnO varistors,traditional aging mechanisms based on increased power consumption are no longer relevant due to reduced power consumption during DC aging.Prolonged exposure to both AC and DC voltages results i...In modern ZnO varistors,traditional aging mechanisms based on increased power consumption are no longer relevant due to reduced power consumption during DC aging.Prolonged exposure to both AC and DC voltages results in increased leakage current,decreased breakdown voltage,and lower nonlinearity,ultimately compromising their protective performance.To investigate the evolution in electrical properties during DC aging,this work developed a finite element model based on Voronoi networks and conducted accelerated aging tests on commercial varistors.Throughout the aging process,current-voltage characteristics and Schottky barrier parameters were measured and analyzed.The results indicate that when subjected to constant voltage,current flows through regions with larger grain sizes,forming discharge channels.As aging progresses,the current focus increases on these channels,leading to a decline in the varistor’s overall performance.Furthermore,analysis of the Schottky barrier parameters shows that the changes in electrical performance during aging are non-monotonic.These findings offer theoretical support for understanding the aging mechanisms and condition assessment of modern stable ZnO varistors.展开更多
Aging is a physiological and complex process produced by accumulative age-dependent cellular damage,which significantly impacts brain regions like the hippocampus,an essential region involved in memory and learning.A ...Aging is a physiological and complex process produced by accumulative age-dependent cellular damage,which significantly impacts brain regions like the hippocampus,an essential region involved in memory and learning.A crucial factor contributing to this decline is the dysfunction of mitochondria,particularly those located at synapses.Synaptic mitochondria are specialized organelles that produce the energy required for synaptic transmission but are also important for calcium homeostasis at these sites.In contrast,non-synaptic mitochondria primarily involve cellular metabolism and long-term energy supply.Both pools of mitochondria differ in their form,proteome,functionality,and cellular role.The proper functioning of synaptic mitochondria depends on processes such as mitochondrial dynamics,transport,and quality control.However,synaptic mitochondria are particularly vulnerable to age-associated damage,characterized by oxidative stress,impaired energy production,and calcium dysregulation.These changes compromise synaptic transmission,reducing synaptic activity and cognitive decline during aging.In the context of neurodegenerative diseases such as Alzheimer’s,Parkinson’s,and Huntington’s,the decline of synaptic mitochondrial function is even more pronounced.These diseases are marked by pathological protein accumulation,disrupted mitochondrial dynamics,and heightened oxidative stress,accelerating synaptic dysfunction and neuronal loss.Due to their specialized role and location,synaptic mitochondria are among the first organelles to exhibit dysfunction,underscoring their critical role in disease progression.This review delves into the main differences at structural and functional levels between synaptic and non-synaptic mitochondria,emphasizing the vulnerability of synaptic mitochondria to the aging process and neurodegeneration.These approaches highlight the potential of targeting synaptic mitochondria to mitigate age-associated cognitive impairment and synaptic degeneration.This review emphasizes the distinct vulnerabilities of hippocampal synaptic mitochondria,highlighting their essential role in sustaining brain function throughout life and their promise as therapeutic targets for safeguarding the cognitive capacities of people of advanced age.展开更多
As the aging population continues to grow,age-related health issues are becoming increasingly prominent,attracting widespread attention and concern from society.While research on the mechanisms of aging is relatively ...As the aging population continues to grow,age-related health issues are becoming increasingly prominent,attracting widespread attention and concern from society.While research on the mechanisms of aging is relatively extensive,studies on the association between aging and related diseases remain limited.G.lucidum,a traditional medicinal fungus,has garnered significant attention due to its diverse bioactive properties.Recent studies have revealed that G.lucidum and its active components exhibit significant potential in anti-aging and regulating dysregulation of glucose and lipid metabolism.However,a comprehensive and detailed review of recent research findings has yet to be thoroughly explored.This paper summarizes and elucidates the latest advances in the pathological mechanisms of aging-related glucose and lipid metabolism disorders by retrieving data from databases such as X-mol and PubMed,provides a detailed account of the regulatory effects of G.lucidum’s primary active components on aging and lipid metabolism,and explores their potential mechanisms.Additionally,it discusses the application prospects of G.lucidum in the fields of anti-aging and metabolic regulation,aiming to provide a reference for research on aging-mediated lipid metabolism disorders and to lay a theoretical foundation for the further development and application of G.lucidum.展开更多
Mitochondrial dysfunction and oxidative stress are widely regarded as primary drivers of aging and are associated with several neurodegenerative diseases.The degeneration of motor neurons during aging is a critical pa...Mitochondrial dysfunction and oxidative stress are widely regarded as primary drivers of aging and are associated with several neurodegenerative diseases.The degeneration of motor neurons during aging is a critical pathological factor contributing to the progression of sarcopenia.However,the morphological and functional changes in mitochondria and their interplay in the degeneration of the neuromuscular junction during aging remain poorly understood.A defined systematic search of the Pub Med,Web of Science and Embase databases(last accessed on October 30,2024)was conducted with search terms including'mitochondria','aging'and'NMJ'.Clinical and preclinical studies of mitochondrial dysfunction and neuromuscular junction degeneration during aging.Twentyseven studies were included in this systematic review.This systematic review provides a summary of morphological,functional and biological changes in neuromuscular junction,mitochondrial morphology,biosynthesis,respiratory chain function,and mitophagy during aging.We focus on the interactions and mechanisms underlying the relationship between mitochondria and neuromuscular junctions during aging.Aging is characterized by significant reductions in mitochondrial fusion/fission cycles,biosynthesis,and mitochondrial quality control,which may lead to neuromuscular junction dysfunction,denervation and poor physical performance.Motor nerve terminals that exhibit redox sensitivity are among the first to exhibit abnormalities,ultimately leading to an early decline in muscle strength through impaired neuromuscular junction transmission function.Parg coactivator 1 alpha is a crucial molecule that regulates mitochondrial biogenesis and modulates various pathways,including the mitochondrial respiratory chain,energy deficiency,oxidative stress,and inflammation.Mitochondrial dysfunction is correlated with neuromuscular junction denervation and acetylcholine receptor fragmentation,resulting in muscle atrophy and a decrease in strength during aging.Physical therapy,pharmacotherapy,and gene therapy can alleviate the structural degeneration and functional deterioration of neuromuscular junction by restoring mitochondrial function.Therefore,mitochondria are considered potential targets for preserving neuromuscular junction morphology and function during aging to treat sarcopenia.展开更多
In recent years,rising life expectancy has led to a significant increase in the prevalence of neurodegenerative disorders,including Alzheimer’s disease(AD),Parkinson’s disease,and age-related cognitive decline.Addit...In recent years,rising life expectancy has led to a significant increase in the prevalence of neurodegenerative disorders,including Alzheimer’s disease(AD),Parkinson’s disease,and age-related cognitive decline.Additionally,other neurological conditions such as glioblastoma,the most common and aggressive brain tumor in adults have been more frequently reported in aging populations.The brain itself is highly vulnerable to age-related changes,particularly disruptions in homeostatic regulation,which further contribute to its functional decline and heightened susceptibility to disease.This has led to a surge of interest in understanding the cellular and molecular mechanisms driving these changes.展开更多
Regenerative medicine is a promising therapeutic avenue for previously incurable diseases.As the risk of chronic and degenerative diseases significantly increases with age,the elderly population represents a major coh...Regenerative medicine is a promising therapeutic avenue for previously incurable diseases.As the risk of chronic and degenerative diseases significantly increases with age,the elderly population represents a major cohort for stem cell-based therapies.However,the regenerative potential of stem cells significantly decreases with advanced age and deteriorating health status of the donor.Therefore,the efficacy of autologous stem cell therapy is significantly compromised in older patients.To overcome these limitations,alternative strategies have been used to restore the age-and disease-depleted function of stem cells.These methods aim to restore the therapeutic efficacy of aged stem cells for autologous use.This article explores the effect of donor age and health status on the regenerative potential of stem cells.It further highlights the limitations of stem cell-based therapy for autologous treatment in the elderly.A comprehensive insight into the potential strategies to address the“age”and“disease”compromised regenerative potential of autologous stem cells is also presented.The information provided here serves as a valuable resource for physicians and patients for optimization of stem cellbased autologous therapy for aged patients.展开更多
The effects of artificial aging(T6)on the creep resistance with tensile stresses in the range of 50−80 MPa at 175℃were investigated for an extruded Mg−1.22Al−0.31Ca−0.44Mn(wt.%)alloy.The Guinier-Preston(G.P.)zones pr...The effects of artificial aging(T6)on the creep resistance with tensile stresses in the range of 50−80 MPa at 175℃were investigated for an extruded Mg−1.22Al−0.31Ca−0.44Mn(wt.%)alloy.The Guinier-Preston(G.P.)zones primarily precipitate in the sample aged at 200℃for 1 h(T6-200℃/1h),while the Al_(2)Ca phases mainly precipitate in the sample aged at 275℃for 8 h(T6-275℃/8h).The T6-200℃/1h sample exhibits excellent creep resistance,with a steady-state creep rate one order of magnitude lower than that of the T6-275℃/8h sample.The abnormally high stress exponent(~8.2)observed in the T6-200℃/1h sample is associated with the power-law breakdown mechanism.TEM analysis illuminates that the creep mechanism for the T6-200℃/1h sample is cross-slip between basal and prismatic dislocations,while the T6-275℃/8h sample exhibits a mixed mechanism of dislocation cross-slip and climb.Compared with the Al_(2)Ca phase,the dense G.P.zones effectively impede dislocation climb and glide during the creep process,demonstrating superior creep resistance of the T6-200℃/1h sample.展开更多
Alzheimer’s disease is initially thought to be caused by age-associated accumulation of plaques,in recent years,research has increasingly associated Alzheimer’s disease with lysosomal storage and metabolic disorders...Alzheimer’s disease is initially thought to be caused by age-associated accumulation of plaques,in recent years,research has increasingly associated Alzheimer’s disease with lysosomal storage and metabolic disorders,and the explanation of its pathogenesis has shifted from amyloid and tau accumulation to oxidative stress and impaired lipid and glucose metabolism aggravated by hypoxic conditions.However,the underlying mechanisms linking those cellular processes and conditions to disease progression have yet to be defined.Here,we applied a disease similarity approach to identify unknown molecular targets of Alzheimer’s disease by using transcriptomic data from congenital diseases known to increase Alzheimer’s disease risk,namely Down syndrome,Niemann-Pick type C disease,and mucopolysaccharidoses I.We uncovered common pathways,hub genes,and miRNAs across in vitro and in vivo models of these diseases as potential molecular targets for neuroprotection and amelioration of Alzheimer’s disease pathology,many of which have never been associated with Alzheimer’s disease.We then investigated common molecular alterations in brain samples from a Niemann-Pick type C disease mouse model by juxtaposing them with brain samples of both human and mouse models of Alzheimer’s disease.Detailed phenotypic,molecular,chronological,and biological aging analyses revealed that the Npc1tm(I1061T)Dso mouse model can serve as a potential short-lived in vivo model for brain aging and Alzheimer’s disease research.This research represents the first comprehensive approach to congenital disease association with neurodegeneration and a new perspective on Alzheimer’s disease research while highlighting shortcomings and lack of correlation in diverse in vitro models.Considering the lack of an Alzheimer’s disease mouse model that recapitulates the physiological hallmarks of brain aging,the short-lived Npc1^(tm(I1061T)Dso) mouse model can further accelerate the research in these fields and offer a unique model for understanding the molecular mechanisms of Alzheimer’s disease from a perspective of accelerated brain aging.展开更多
The aging process is an inexorable fact throughout our lives and is considered a major factor in develo ping neurological dysfunctions associated with cognitive,emotional,and motor impairments.Aging-associated neurode...The aging process is an inexorable fact throughout our lives and is considered a major factor in develo ping neurological dysfunctions associated with cognitive,emotional,and motor impairments.Aging-associated neurodegenerative diseases are characterized by the progressive loss of neuronal structure and function.展开更多
Lexical analysis is a fundamental task in natural language processing,which involves several subtasks,such as word segmentation(WS),part-of-speech(POS)tagging,and named entity recognition(NER).Recent works have shown ...Lexical analysis is a fundamental task in natural language processing,which involves several subtasks,such as word segmentation(WS),part-of-speech(POS)tagging,and named entity recognition(NER).Recent works have shown that taking advantage of relatedness between these subtasks can be beneficial.This paper proposes a unified neural framework to address these subtasks simultaneously.Apart from the sequence tagging paradigm,the proposed method tackles the multitask lexical analysis via two-stage sequence span classification.Firstly,the model detects the word and named entity boundaries by multilabel classification over character spans in a sentence.Then,the authors assign POS labels and entity labels for words and named entities by multi-class classification,respectively.Furthermore,a Gated Task Transformation(GTT)is proposed to encourage the model to share valuable features between tasks.The performance of the proposed model was evaluated on Chinese and Thai public datasets,demonstrating state-of-the-art results.展开更多
The Thyristor-Controlled Series Compensator(TCSC)presents an effective solution for mitigating transmission congestion in power systems by regulating the distribution of line power flow.However,inherent faults within ...The Thyristor-Controlled Series Compensator(TCSC)presents an effective solution for mitigating transmission congestion in power systems by regulating the distribution of line power flow.However,inherent faults within the TCSC may lead to an unintended intensification of transmission congestion in other sections of the system post-installation,resulting in non-coherent phenomena of line blocking.In response to this challenge,this paper introduces a novel two-stage site selectionmethod for TCSC,emphasizing the enhancement of coherence in addressing line-blocking issues.Through rigorous non-coherent verification,this method mitigates the risk of line congestion deterioration due to TCSC faults.In the initial stage of the proposed method,TCSC faults are not considered during the extraction of system states.System state analysis is performed based on the TCSC site selection model,aiming to minimize system load reduction.The preliminary recommended installation position for TCSC is determined by sorting the frequency of TCSC installation occurrences on lines extracted from the analyzed system states.In the subsequent stage,accounting for the influence of TCSC faults on line faults,system operating states are extracted.Line and system congestion indices are calculated through the statistical analysis of the system state analysis results.The installation of TCSC at the preliminary position is scrutinized to identify non-coherent phenomena of line congestion on other lines.If such phenomena are observed,the installation position is excluded,and the TCSC site selection process is reinitiated based on the methodology from the first stage.To validate the effectiveness of the proposed method,a case study is conducted on a modified RBTS test system.The case study results indicate that,compared with TCSC siting schemes that do not consider transmission congestion non-coherency,the proposed non-coherency-based siting scheme reduces the system congestion expectation(SCE)and system congestion probability(SCP)by 17.7%and 11.4%,respectively,while lowering the LOLP and EENS by 2.56% and 4.55%,respectively.These results demonstrate that the proposed method can effectively alleviate transmission congestion and enhance the overall reliability of the system.展开更多
Applying bio-oxidation waste solution(BOS)to chemical-biological two-stage oxidation process can significantly improve the bio-oxidation efficiency of arsenopyrite.This study aims to clarify the enhanced oxidation mec...Applying bio-oxidation waste solution(BOS)to chemical-biological two-stage oxidation process can significantly improve the bio-oxidation efficiency of arsenopyrite.This study aims to clarify the enhanced oxidation mechanism of arsenopyrite by evaluating the effects of physical and chemical changes of arsenopyrite in BOS chemical oxidation stage on mineral dissolution kinetics,as well as microbial growth activity and community structure composition in bio-oxidation stage.The results showed that the chemical oxidation contributed to destroying the physical and chemical structure of arsenopyrite surface and reducing the particle size,and led to the formation of nitrogenous substances on mineral surface.These chemical oxidation behaviors effectively promoted Fe^(3+)cycling in the bio-oxidation system and weakened the inhibitory effect of the sulfur film on ionic diffusion,thereby enhancing the dissolution kinetics of the arsenopyrite.Therefore,the bio-oxidation efficiency of arsenopyrite was significantly increased in the two-stage oxidation process.After 18 d,the two-stage oxidation process achieved total extraction rates of(88.8±2.0)%,(86.7±1.3)%,and(74.7±3.0)%for As,Fe,and S elements,respectively.These values represented a significant increase of(50.8±3.4)%,(47.1±2.7)%,and(46.0±0.7)%,respectively,compared to the one-stage bio-oxidation process.展开更多
Exploring the factors driving the decoupling of China’s sulfur dioxide(SO_(2))emissions from economic growth(DEI)is crucial for achieving sustainable development.By analyzing the decoupling indicators and driving fac...Exploring the factors driving the decoupling of China’s sulfur dioxide(SO_(2))emissions from economic growth(DEI)is crucial for achieving sustainable development.By analyzing the decoupling indicators and driving factors at both the generation and treatment stages of SO_(2),more effective targeted mitigation strategies can be developed.We employ the Tapio decoupling model and propose a two-stage method to examine the decoupling issues related to SO_(2).Our findings indicate that:①DEI shows a steady and significant improvement,with SO_(2)emission intensity identified as the primary driver.②for the decoupling of economic growth and SO_(2)generation,energy scale serves as the largest stimulator,while the effect of energy intensity changes from negative to positive,and pollution intensity is first positive and then negative.③For the decoupling of SO_(2)generation and SO_(2)removal,treatment efficiency leads as the largest promoter,followed by treatment intensity.Based on these results,this study recommends that China focuses more on enhancing clean energy utilization and the effectiveness of treatment processes.展开更多
BACKGROUND Two-stage revision is the most common treatment for chronic periprosthetic joint infection of the hip,involving a resection arthroplasty with or without placement of an antibiotic-loaded spacer,followed by ...BACKGROUND Two-stage revision is the most common treatment for chronic periprosthetic joint infection of the hip,involving a resection arthroplasty with or without placement of an antibiotic-loaded spacer,followed by antibiotic therapy before reimplantation.AIM To compare the outcomes and complications of two consecutive treatment protocols for two-stage revision arthroplasty of the infected hip:One using Girdlestone with an antibiotic holiday,the other using custom-made articulating spacers(CUMARS)without an antibiotic holiday.METHODS In this retrospective study,two consecutive cohorts were compared.Group A(2017-2020)underwent two-stage revision with a Girdlestone and an antibiotic holiday before reimplantation,while Group B(2020-2023)received CUMARS whenever possible,and no antibiotic holiday,or a Girdlestone if indicated.The primary outcome was successful infection eradication after one year.Secondary outcomes included surgical duration,length of hospital stay,weight-bearing allowance,discharge destination,and complications.RESULTS A total of 98 patients were included:39 patients in Group A and 59 patients in Group B.Successful infection eradication after one year was achieved in 69%of Group A and 83%of Group B(P=0.164).Patients in Group B were more frequently allowed to bear weight(64%vs 18%,P<0.001),had a shorter in-hospital stay(9 vs 16 days,P<0.001),and were more often discharged home after the first surgery(48%vs 24%,P=0.048).No significant differences were found in(mechanical)complications.CONCLUSION A protocol including CUMARS is a safe and effective treatment,offering faster recovery,shorter length of hospital stay,and enabling more patients to return home during the interval.This reduces strain on patients and the healthcare system,potentially saving costs,without compromising infection control or increasing(mechanical)complications.展开更多
Micro-nano Earth Observation Satellite(MEOS)constellation has the advantages of low construction cost,short revisit cycle,and high functional density,which is considered a promising solution for serving rapidly growin...Micro-nano Earth Observation Satellite(MEOS)constellation has the advantages of low construction cost,short revisit cycle,and high functional density,which is considered a promising solution for serving rapidly growing observation demands.The observation Scheduling Problem in the MEOS constellation(MEOSSP)is a challenging issue due to the large number of satellites and tasks,as well as complex observation constraints.To address the large-scale and complicated MEOSSP,we develop a Two-Stage Scheduling Algorithm based on the Pointer Network with Attention mechanism(TSSA-PNA).In TSSA-PNA,the MEOS observation scheduling is decomposed into a task allocation stage and a single-MEOS scheduling stage.In the task allocation stage,an adaptive task allocation algorithm with four problem-specific allocation operators is proposed to reallocate the unscheduled tasks to new MEOSs.Regarding the single-MEOS scheduling stage,we design a pointer network based on the encoder-decoder architecture to learn the optimal singleMEOS scheduling solution and introduce the attention mechanism into the encoder to improve the learning efficiency.The Pointer Network with Attention mechanism(PNA)can generate the single-MEOS scheduling solution quickly in an end-to-end manner.These two decomposed stages are performed iteratively to search for the solution with high profit.A greedy local search algorithm is developed to improve the profits further.The performance of the PNA and TSSA-PNA on singleMEOS and multi-MEOS scheduling problems are evaluated in the experiments.The experimental results demonstrate that PNA can obtain the approximate solution for the single-MEOS scheduling problem in a short time.Besides,the TSSA-PNA can achieve higher observation profits than the existing scheduling algorithms within the acceptable computational time for the large-scale MEOS scheduling problem.展开更多
The development of efficient and clean heating technologies is crucial for reducing carbon emissions in regions with severe cold regions.This research designs a novel two-stage phase change heat storage coupled solar-...The development of efficient and clean heating technologies is crucial for reducing carbon emissions in regions with severe cold regions.This research designs a novel two-stage phase change heat storage coupled solar-air source heat pump heating system structure that is specifically designed for such regions.The two-stage heat storage device in this heating system expands the storage temperature range of solar heat.The utilization of the two-stage heat storage device not onlymakes up for the instability of the solar heating system,but can also directlymeet the building heating temperature,and can reduce the influence of low-temperature outdoor environments in severe cold regions on the heating performance of the air source heat pump by using solar energy.Therefore,the two-stage phase change heat storage coupled to the solar energy-air source heat pump heating system effectively improves the utilization rate of solar energy.A numerical model of the system components and their integration was developed using TRNSYS software in this study,and various performance aspects of the system were simulated and analyzed.The simulation results demonstrated that the two-stage heat storage device can effectively store solar energy,enabling its hierarchical utilization.The low-temperature solar energy stored by the two-stage phase change heat storage device enhances the coefficient of performance of the air source heat pump by 11.1%in severe cold conditions.Using the Hooke-Jeeves optimization method,the annual cost and carbon emissions are taken as optimization objectives,with the optimized solar heat supply accounting for 52.5%.This study offers valuable insights into operational strategies and site selection for engineering applications,providing a solid theoretical foundation for the widespread implementation of this system in severe cold regions.展开更多
基金supported by the National Key Research and Development Program of China(Nos.2016YFB0301101 and 2016YFB0301000)the Key Science and Technology Program of Beijing Municipal Commission of Education(No.KZ201810005005)+1 种基金the National Natural Science Fund of China(No.51801004)the Beijing Natural Science Foundation(No.2192006)。
文摘The Mg–12Gd–1Er–1Zn–0.9 Zr(wt%)alloy with ultra-high strength and ductility was developed via hot extrusion combined with pre-deformation and two-stage aging treatment.The age-hardening behavior and microstructure evolution were investigated.Pre-deformation introduced a large number of dislocations,resulting in strain hardening and higher precipitation strengthening in the subsequent two-stage aging.As a result,the alloy showed a superior strength–ductility balance with a yield strength of 506 MPa,an ultimate tensile strength of 549 MPa and an elongation of 8.2%at room temperature.The finer and denserβ’precipitates significantly enhanced the strength,and the bimodal structure,smallβ-Mg5RE phase as well as denseγ’precipitates ensured the good ductility of the alloy.It is suggested that the combination of pre-deformation and two-stage aging treatment is an eff ective method to further improve the mechanical properties of wrought Mg alloys.
基金Project(2005CB623706) supported by the National Basic Research Program of China
文摘The effect of two-stage aging on the microstructures and superplasticity of 01420 Al-Li alloy was investigated by means of OM, TEM analysis and stretching experiment. The results demonstrate that the second phase particles distributed more uniformly with a larger volume fraction can be observed after the two-stage aging (120℃, 12 h+300℃, 36 h) compared with the single-aging(300℃, 48 h). After rolling and recrystallization annealing, fine grains with size of 8-10 urn are obtained, and the superplastic elongation of the specimens reaches 560% at strain rate of 8×10-4s-1 and 480℃. Uniformly distributed fine particles precipitate both on grain boundaries and in grains at lower temperature. When the sheet is aged at high temperature, the particles become coarser with a large volume fraction.
基金supported by the National Key R&D Program of China(No.2021YFB3400900)the National Natural Science Foundation of China(Nos.52175373,52205435)+1 种基金Natural Science Foundation of Hunan Province,China(No.2022JJ40621)the Innovation Fund of National Commercial Aircraft Manufacturing Engineering Technology Center,China(No.COMACSFGS-2022-1875)。
文摘A new unified constitutive model was developed to predict the two-stage creep-aging(TSCA)behavior of Al-Zn-Mg-Cu alloys.The particular bimodal precipitation feature was analyzed and modeled by considering the primary micro-variables evolution at different temperatures and their interaction.The dislocation density was incorporated into the model to capture the effect of creep deformation on precipitation.Quantitative transmission electron microscopy and experimental data obtained from a previous study were used to calibrate the model.Subsequently,the developed constitutive model was implemented in the finite element(FE)software ABAQUS via the user subroutines for TSCA process simulation and the springback prediction of an integral panel.A TSCA test was performed.The result shows that the maximum radius deviation between the formed plate and the simulation results is less than 0.4 mm,thus validating the effectiveness of the developed constitutive model and FE model.
基金supported by Science Foundation Ireland (Grant 19/FFP/6666),Cure Parkinson’s (Grant CP:GO01)a PhD studentship from the Anatomical Society。
文摘SKI family transcriptional corepressor 1(SKOR1also known as LbxCor1, Fussel15, or CORL1), is a member of the SKI family of proteins and is transcribed from a protein-coding gene located on chromosome 15 in humans, that has a molecular weight of approximately 100 kDa. Skor1 is highly expressed in neurons in the central nervous system of both humans and rodents.
文摘In modern ZnO varistors,traditional aging mechanisms based on increased power consumption are no longer relevant due to reduced power consumption during DC aging.Prolonged exposure to both AC and DC voltages results in increased leakage current,decreased breakdown voltage,and lower nonlinearity,ultimately compromising their protective performance.To investigate the evolution in electrical properties during DC aging,this work developed a finite element model based on Voronoi networks and conducted accelerated aging tests on commercial varistors.Throughout the aging process,current-voltage characteristics and Schottky barrier parameters were measured and analyzed.The results indicate that when subjected to constant voltage,current flows through regions with larger grain sizes,forming discharge channels.As aging progresses,the current focus increases on these channels,leading to a decline in the varistor’s overall performance.Furthermore,analysis of the Schottky barrier parameters shows that the changes in electrical performance during aging are non-monotonic.These findings offer theoretical support for understanding the aging mechanisms and condition assessment of modern stable ZnO varistors.
基金supported by ANID FONDECYT No.1221178Centro Ciencia&Vida,FB210008,Financiamiento Basal para Centros Científicos y Tecnológicos de Excelencia de ANID to CTR.
文摘Aging is a physiological and complex process produced by accumulative age-dependent cellular damage,which significantly impacts brain regions like the hippocampus,an essential region involved in memory and learning.A crucial factor contributing to this decline is the dysfunction of mitochondria,particularly those located at synapses.Synaptic mitochondria are specialized organelles that produce the energy required for synaptic transmission but are also important for calcium homeostasis at these sites.In contrast,non-synaptic mitochondria primarily involve cellular metabolism and long-term energy supply.Both pools of mitochondria differ in their form,proteome,functionality,and cellular role.The proper functioning of synaptic mitochondria depends on processes such as mitochondrial dynamics,transport,and quality control.However,synaptic mitochondria are particularly vulnerable to age-associated damage,characterized by oxidative stress,impaired energy production,and calcium dysregulation.These changes compromise synaptic transmission,reducing synaptic activity and cognitive decline during aging.In the context of neurodegenerative diseases such as Alzheimer’s,Parkinson’s,and Huntington’s,the decline of synaptic mitochondrial function is even more pronounced.These diseases are marked by pathological protein accumulation,disrupted mitochondrial dynamics,and heightened oxidative stress,accelerating synaptic dysfunction and neuronal loss.Due to their specialized role and location,synaptic mitochondria are among the first organelles to exhibit dysfunction,underscoring their critical role in disease progression.This review delves into the main differences at structural and functional levels between synaptic and non-synaptic mitochondria,emphasizing the vulnerability of synaptic mitochondria to the aging process and neurodegeneration.These approaches highlight the potential of targeting synaptic mitochondria to mitigate age-associated cognitive impairment and synaptic degeneration.This review emphasizes the distinct vulnerabilities of hippocampal synaptic mitochondria,highlighting their essential role in sustaining brain function throughout life and their promise as therapeutic targets for safeguarding the cognitive capacities of people of advanced age.
基金supported by grants from Natural Science Foundation of Jilin Province(No.23JQ08,No.YDZJ202502 CXJD077,No.JLARS-2025-0802-09 and No.YDZJ202501ZY TS706).
文摘As the aging population continues to grow,age-related health issues are becoming increasingly prominent,attracting widespread attention and concern from society.While research on the mechanisms of aging is relatively extensive,studies on the association between aging and related diseases remain limited.G.lucidum,a traditional medicinal fungus,has garnered significant attention due to its diverse bioactive properties.Recent studies have revealed that G.lucidum and its active components exhibit significant potential in anti-aging and regulating dysregulation of glucose and lipid metabolism.However,a comprehensive and detailed review of recent research findings has yet to be thoroughly explored.This paper summarizes and elucidates the latest advances in the pathological mechanisms of aging-related glucose and lipid metabolism disorders by retrieving data from databases such as X-mol and PubMed,provides a detailed account of the regulatory effects of G.lucidum’s primary active components on aging and lipid metabolism,and explores their potential mechanisms.Additionally,it discusses the application prospects of G.lucidum in the fields of anti-aging and metabolic regulation,aiming to provide a reference for research on aging-mediated lipid metabolism disorders and to lay a theoretical foundation for the further development and application of G.lucidum.
基金supported by grants from Collaborative Research Fund(Ref:C4032-21GF)General Research Grant(Ref:14114822)+1 种基金Group Research Scheme(Ref:3110146)Area of Excellence(Ref:Ao E/M-402/20)。
文摘Mitochondrial dysfunction and oxidative stress are widely regarded as primary drivers of aging and are associated with several neurodegenerative diseases.The degeneration of motor neurons during aging is a critical pathological factor contributing to the progression of sarcopenia.However,the morphological and functional changes in mitochondria and their interplay in the degeneration of the neuromuscular junction during aging remain poorly understood.A defined systematic search of the Pub Med,Web of Science and Embase databases(last accessed on October 30,2024)was conducted with search terms including'mitochondria','aging'and'NMJ'.Clinical and preclinical studies of mitochondrial dysfunction and neuromuscular junction degeneration during aging.Twentyseven studies were included in this systematic review.This systematic review provides a summary of morphological,functional and biological changes in neuromuscular junction,mitochondrial morphology,biosynthesis,respiratory chain function,and mitophagy during aging.We focus on the interactions and mechanisms underlying the relationship between mitochondria and neuromuscular junctions during aging.Aging is characterized by significant reductions in mitochondrial fusion/fission cycles,biosynthesis,and mitochondrial quality control,which may lead to neuromuscular junction dysfunction,denervation and poor physical performance.Motor nerve terminals that exhibit redox sensitivity are among the first to exhibit abnormalities,ultimately leading to an early decline in muscle strength through impaired neuromuscular junction transmission function.Parg coactivator 1 alpha is a crucial molecule that regulates mitochondrial biogenesis and modulates various pathways,including the mitochondrial respiratory chain,energy deficiency,oxidative stress,and inflammation.Mitochondrial dysfunction is correlated with neuromuscular junction denervation and acetylcholine receptor fragmentation,resulting in muscle atrophy and a decrease in strength during aging.Physical therapy,pharmacotherapy,and gene therapy can alleviate the structural degeneration and functional deterioration of neuromuscular junction by restoring mitochondrial function.Therefore,mitochondria are considered potential targets for preserving neuromuscular junction morphology and function during aging to treat sarcopenia.
基金supported by the Swedish ResearchCouncil and the Swedish Brain Foundation,theCancer Research Funds of Radiumhemmet,theStrategic Research Area in Cancer(StratCan),the Strategic Research Area in Neuroscience(StratNeuro),the Swedish Cancer Society,theSwedish Childhood Cancer Foundation,theKarolinska Institutet Foundation,the InnoHKinitiative of the Innovation and TechnologyCommission of the Hong Kong SpecialAdministrative Region Government(to BJ).Openaccess funding is provided by the KarolinskaInstitute.
文摘In recent years,rising life expectancy has led to a significant increase in the prevalence of neurodegenerative disorders,including Alzheimer’s disease(AD),Parkinson’s disease,and age-related cognitive decline.Additionally,other neurological conditions such as glioblastoma,the most common and aggressive brain tumor in adults have been more frequently reported in aging populations.The brain itself is highly vulnerable to age-related changes,particularly disruptions in homeostatic regulation,which further contribute to its functional decline and heightened susceptibility to disease.This has led to a surge of interest in understanding the cellular and molecular mechanisms driving these changes.
文摘Regenerative medicine is a promising therapeutic avenue for previously incurable diseases.As the risk of chronic and degenerative diseases significantly increases with age,the elderly population represents a major cohort for stem cell-based therapies.However,the regenerative potential of stem cells significantly decreases with advanced age and deteriorating health status of the donor.Therefore,the efficacy of autologous stem cell therapy is significantly compromised in older patients.To overcome these limitations,alternative strategies have been used to restore the age-and disease-depleted function of stem cells.These methods aim to restore the therapeutic efficacy of aged stem cells for autologous use.This article explores the effect of donor age and health status on the regenerative potential of stem cells.It further highlights the limitations of stem cell-based therapy for autologous treatment in the elderly.A comprehensive insight into the potential strategies to address the“age”and“disease”compromised regenerative potential of autologous stem cells is also presented.The information provided here serves as a valuable resource for physicians and patients for optimization of stem cellbased autologous therapy for aged patients.
基金supported by the National Natural Science Foundation of China (Nos. 52175322, 52271031)the Natural Science Foundation of Jilin Province, China (No. SKL202302015)。
文摘The effects of artificial aging(T6)on the creep resistance with tensile stresses in the range of 50−80 MPa at 175℃were investigated for an extruded Mg−1.22Al−0.31Ca−0.44Mn(wt.%)alloy.The Guinier-Preston(G.P.)zones primarily precipitate in the sample aged at 200℃for 1 h(T6-200℃/1h),while the Al_(2)Ca phases mainly precipitate in the sample aged at 275℃for 8 h(T6-275℃/8h).The T6-200℃/1h sample exhibits excellent creep resistance,with a steady-state creep rate one order of magnitude lower than that of the T6-275℃/8h sample.The abnormally high stress exponent(~8.2)observed in the T6-200℃/1h sample is associated with the power-law breakdown mechanism.TEM analysis illuminates that the creep mechanism for the T6-200℃/1h sample is cross-slip between basal and prismatic dislocations,while the T6-275℃/8h sample exhibits a mixed mechanism of dislocation cross-slip and climb.Compared with the Al_(2)Ca phase,the dense G.P.zones effectively impede dislocation climb and glide during the creep process,demonstrating superior creep resistance of the T6-200℃/1h sample.
基金supported by the NIA/NIH(1K01AG060040).Studies performed by JN were funded by the NICHD/NIH(5R00HD096117)Microscopy Core Facility supported,in part,with funding from NIH-NCI Cancer Center Support Grant P30 CA016059.
文摘Alzheimer’s disease is initially thought to be caused by age-associated accumulation of plaques,in recent years,research has increasingly associated Alzheimer’s disease with lysosomal storage and metabolic disorders,and the explanation of its pathogenesis has shifted from amyloid and tau accumulation to oxidative stress and impaired lipid and glucose metabolism aggravated by hypoxic conditions.However,the underlying mechanisms linking those cellular processes and conditions to disease progression have yet to be defined.Here,we applied a disease similarity approach to identify unknown molecular targets of Alzheimer’s disease by using transcriptomic data from congenital diseases known to increase Alzheimer’s disease risk,namely Down syndrome,Niemann-Pick type C disease,and mucopolysaccharidoses I.We uncovered common pathways,hub genes,and miRNAs across in vitro and in vivo models of these diseases as potential molecular targets for neuroprotection and amelioration of Alzheimer’s disease pathology,many of which have never been associated with Alzheimer’s disease.We then investigated common molecular alterations in brain samples from a Niemann-Pick type C disease mouse model by juxtaposing them with brain samples of both human and mouse models of Alzheimer’s disease.Detailed phenotypic,molecular,chronological,and biological aging analyses revealed that the Npc1tm(I1061T)Dso mouse model can serve as a potential short-lived in vivo model for brain aging and Alzheimer’s disease research.This research represents the first comprehensive approach to congenital disease association with neurodegeneration and a new perspective on Alzheimer’s disease research while highlighting shortcomings and lack of correlation in diverse in vitro models.Considering the lack of an Alzheimer’s disease mouse model that recapitulates the physiological hallmarks of brain aging,the short-lived Npc1^(tm(I1061T)Dso) mouse model can further accelerate the research in these fields and offer a unique model for understanding the molecular mechanisms of Alzheimer’s disease from a perspective of accelerated brain aging.
文摘The aging process is an inexorable fact throughout our lives and is considered a major factor in develo ping neurological dysfunctions associated with cognitive,emotional,and motor impairments.Aging-associated neurodegenerative diseases are characterized by the progressive loss of neuronal structure and function.
基金supported by National Natural Science Foundation of China(Grant No.62266028,62266027,U21B2027,and U24A20334)Major Science and Technology Programs in Yunnan Province(Grant No.202302AD080003,202402AG050007,and 202303AP140008)+1 种基金Yunnan Province Basic Research Program(Grant No.202301AS070047,202301AT070471,and 202401BC070021)Kunming University of Science and Technology's"Double First-rate"construction joint project(Grant No.202201BE070001-021).
文摘Lexical analysis is a fundamental task in natural language processing,which involves several subtasks,such as word segmentation(WS),part-of-speech(POS)tagging,and named entity recognition(NER).Recent works have shown that taking advantage of relatedness between these subtasks can be beneficial.This paper proposes a unified neural framework to address these subtasks simultaneously.Apart from the sequence tagging paradigm,the proposed method tackles the multitask lexical analysis via two-stage sequence span classification.Firstly,the model detects the word and named entity boundaries by multilabel classification over character spans in a sentence.Then,the authors assign POS labels and entity labels for words and named entities by multi-class classification,respectively.Furthermore,a Gated Task Transformation(GTT)is proposed to encourage the model to share valuable features between tasks.The performance of the proposed model was evaluated on Chinese and Thai public datasets,demonstrating state-of-the-art results.
基金supported by Graduate Research and Innovation Program Project of Nanjing Institute of Technology(No.TB202517078).
文摘The Thyristor-Controlled Series Compensator(TCSC)presents an effective solution for mitigating transmission congestion in power systems by regulating the distribution of line power flow.However,inherent faults within the TCSC may lead to an unintended intensification of transmission congestion in other sections of the system post-installation,resulting in non-coherent phenomena of line blocking.In response to this challenge,this paper introduces a novel two-stage site selectionmethod for TCSC,emphasizing the enhancement of coherence in addressing line-blocking issues.Through rigorous non-coherent verification,this method mitigates the risk of line congestion deterioration due to TCSC faults.In the initial stage of the proposed method,TCSC faults are not considered during the extraction of system states.System state analysis is performed based on the TCSC site selection model,aiming to minimize system load reduction.The preliminary recommended installation position for TCSC is determined by sorting the frequency of TCSC installation occurrences on lines extracted from the analyzed system states.In the subsequent stage,accounting for the influence of TCSC faults on line faults,system operating states are extracted.Line and system congestion indices are calculated through the statistical analysis of the system state analysis results.The installation of TCSC at the preliminary position is scrutinized to identify non-coherent phenomena of line congestion on other lines.If such phenomena are observed,the installation position is excluded,and the TCSC site selection process is reinitiated based on the methodology from the first stage.To validate the effectiveness of the proposed method,a case study is conducted on a modified RBTS test system.The case study results indicate that,compared with TCSC siting schemes that do not consider transmission congestion non-coherency,the proposed non-coherency-based siting scheme reduces the system congestion expectation(SCE)and system congestion probability(SCP)by 17.7%and 11.4%,respectively,while lowering the LOLP and EENS by 2.56% and 4.55%,respectively.These results demonstrate that the proposed method can effectively alleviate transmission congestion and enhance the overall reliability of the system.
基金Project(52274348)supported by the National Natural Science Foundation of ChinaProject(2022JH1/10400024)supported by the Major Projects for the“Revealed Top”Science and Technology of Liaoning Province,China。
文摘Applying bio-oxidation waste solution(BOS)to chemical-biological two-stage oxidation process can significantly improve the bio-oxidation efficiency of arsenopyrite.This study aims to clarify the enhanced oxidation mechanism of arsenopyrite by evaluating the effects of physical and chemical changes of arsenopyrite in BOS chemical oxidation stage on mineral dissolution kinetics,as well as microbial growth activity and community structure composition in bio-oxidation stage.The results showed that the chemical oxidation contributed to destroying the physical and chemical structure of arsenopyrite surface and reducing the particle size,and led to the formation of nitrogenous substances on mineral surface.These chemical oxidation behaviors effectively promoted Fe^(3+)cycling in the bio-oxidation system and weakened the inhibitory effect of the sulfur film on ionic diffusion,thereby enhancing the dissolution kinetics of the arsenopyrite.Therefore,the bio-oxidation efficiency of arsenopyrite was significantly increased in the two-stage oxidation process.After 18 d,the two-stage oxidation process achieved total extraction rates of(88.8±2.0)%,(86.7±1.3)%,and(74.7±3.0)%for As,Fe,and S elements,respectively.These values represented a significant increase of(50.8±3.4)%,(47.1±2.7)%,and(46.0±0.7)%,respectively,compared to the one-stage bio-oxidation process.
基金the National Natural Science Foundation of China[Grant No.52270183].
文摘Exploring the factors driving the decoupling of China’s sulfur dioxide(SO_(2))emissions from economic growth(DEI)is crucial for achieving sustainable development.By analyzing the decoupling indicators and driving factors at both the generation and treatment stages of SO_(2),more effective targeted mitigation strategies can be developed.We employ the Tapio decoupling model and propose a two-stage method to examine the decoupling issues related to SO_(2).Our findings indicate that:①DEI shows a steady and significant improvement,with SO_(2)emission intensity identified as the primary driver.②for the decoupling of economic growth and SO_(2)generation,energy scale serves as the largest stimulator,while the effect of energy intensity changes from negative to positive,and pollution intensity is first positive and then negative.③For the decoupling of SO_(2)generation and SO_(2)removal,treatment efficiency leads as the largest promoter,followed by treatment intensity.Based on these results,this study recommends that China focuses more on enhancing clean energy utilization and the effectiveness of treatment processes.
文摘BACKGROUND Two-stage revision is the most common treatment for chronic periprosthetic joint infection of the hip,involving a resection arthroplasty with or without placement of an antibiotic-loaded spacer,followed by antibiotic therapy before reimplantation.AIM To compare the outcomes and complications of two consecutive treatment protocols for two-stage revision arthroplasty of the infected hip:One using Girdlestone with an antibiotic holiday,the other using custom-made articulating spacers(CUMARS)without an antibiotic holiday.METHODS In this retrospective study,two consecutive cohorts were compared.Group A(2017-2020)underwent two-stage revision with a Girdlestone and an antibiotic holiday before reimplantation,while Group B(2020-2023)received CUMARS whenever possible,and no antibiotic holiday,or a Girdlestone if indicated.The primary outcome was successful infection eradication after one year.Secondary outcomes included surgical duration,length of hospital stay,weight-bearing allowance,discharge destination,and complications.RESULTS A total of 98 patients were included:39 patients in Group A and 59 patients in Group B.Successful infection eradication after one year was achieved in 69%of Group A and 83%of Group B(P=0.164).Patients in Group B were more frequently allowed to bear weight(64%vs 18%,P<0.001),had a shorter in-hospital stay(9 vs 16 days,P<0.001),and were more often discharged home after the first surgery(48%vs 24%,P=0.048).No significant differences were found in(mechanical)complications.CONCLUSION A protocol including CUMARS is a safe and effective treatment,offering faster recovery,shorter length of hospital stay,and enabling more patients to return home during the interval.This reduces strain on patients and the healthcare system,potentially saving costs,without compromising infection control or increasing(mechanical)complications.
基金supported by the National Natural Science Foundation of China(No.62101587)the National Funded Postdoctoral Researcher Program of China(No.GZC20233578)。
文摘Micro-nano Earth Observation Satellite(MEOS)constellation has the advantages of low construction cost,short revisit cycle,and high functional density,which is considered a promising solution for serving rapidly growing observation demands.The observation Scheduling Problem in the MEOS constellation(MEOSSP)is a challenging issue due to the large number of satellites and tasks,as well as complex observation constraints.To address the large-scale and complicated MEOSSP,we develop a Two-Stage Scheduling Algorithm based on the Pointer Network with Attention mechanism(TSSA-PNA).In TSSA-PNA,the MEOS observation scheduling is decomposed into a task allocation stage and a single-MEOS scheduling stage.In the task allocation stage,an adaptive task allocation algorithm with four problem-specific allocation operators is proposed to reallocate the unscheduled tasks to new MEOSs.Regarding the single-MEOS scheduling stage,we design a pointer network based on the encoder-decoder architecture to learn the optimal singleMEOS scheduling solution and introduce the attention mechanism into the encoder to improve the learning efficiency.The Pointer Network with Attention mechanism(PNA)can generate the single-MEOS scheduling solution quickly in an end-to-end manner.These two decomposed stages are performed iteratively to search for the solution with high profit.A greedy local search algorithm is developed to improve the profits further.The performance of the PNA and TSSA-PNA on singleMEOS and multi-MEOS scheduling problems are evaluated in the experiments.The experimental results demonstrate that PNA can obtain the approximate solution for the single-MEOS scheduling problem in a short time.Besides,the TSSA-PNA can achieve higher observation profits than the existing scheduling algorithms within the acceptable computational time for the large-scale MEOS scheduling problem.
基金This work was supported by the project of the Research on Energy Consumption of Office Space in Colleges and Universities under the“Dual Carbon Target”(No.CJ202301006).
文摘The development of efficient and clean heating technologies is crucial for reducing carbon emissions in regions with severe cold regions.This research designs a novel two-stage phase change heat storage coupled solar-air source heat pump heating system structure that is specifically designed for such regions.The two-stage heat storage device in this heating system expands the storage temperature range of solar heat.The utilization of the two-stage heat storage device not onlymakes up for the instability of the solar heating system,but can also directlymeet the building heating temperature,and can reduce the influence of low-temperature outdoor environments in severe cold regions on the heating performance of the air source heat pump by using solar energy.Therefore,the two-stage phase change heat storage coupled to the solar energy-air source heat pump heating system effectively improves the utilization rate of solar energy.A numerical model of the system components and their integration was developed using TRNSYS software in this study,and various performance aspects of the system were simulated and analyzed.The simulation results demonstrated that the two-stage heat storage device can effectively store solar energy,enabling its hierarchical utilization.The low-temperature solar energy stored by the two-stage phase change heat storage device enhances the coefficient of performance of the air source heat pump by 11.1%in severe cold conditions.Using the Hooke-Jeeves optimization method,the annual cost and carbon emissions are taken as optimization objectives,with the optimized solar heat supply accounting for 52.5%.This study offers valuable insights into operational strategies and site selection for engineering applications,providing a solid theoretical foundation for the widespread implementation of this system in severe cold regions.
