Data-driven source-load robust optimal scheduling of integrated energy production unit including hydrogen energy coupling

A robust low-carbon economic optimal scheduling method that considers source-load uncertainty and hydrogen energy utilization is developed.The proposed method overcomes the challenge of source-load random fluctuations in integrated energy systems(IESs)in the operation scheduling problem of integrated energy production units(IEPUs).First,to solve the problem of inaccurate prediction of renewable energy output,an improved robust kernel density estimation method is proposed to construct a data-driven uncertainty output set of renewable energy sources statistically and build a typical scenario of load uncertainty using stochastic scenario reduction.Subsequently,to resolve the problem of insufficient utilization of hydrogen energy in existing IEPUs,a robust low-carbon economic optimal scheduling model of the source-load interaction of an IES with a hydrogen energy system is established.The system considers the further utilization of energy using hydrogen energy coupling equipment(such as hydrogen storage devices and fuel cells)and the comprehensive demand response of load-side schedulable resources.The simulation results show that the proposed robust stochastic optimization model driven by data can effectively reduce carbon dioxide emissions,improve the source-load interaction of the IES,realize the efficient use of hydrogen energy,and improve system robustness.

Multi-physics analysis of the galvanic corrosion of Mg-steel couple under the influence of time-dependent anisotropic deposition film

The anisotropic deposit film formed during the galvanic corrosion can impede the mass transfer of the involved species,thereby affecting the electro-chemical behavior and the evolution of galvanic corrosion.The limitations of experimental studies in the spatial-temporal scales restrict a deeper understanding of the corrosion mechanism,which can be complemented by numerical simulation.A multi-physics coupled model is proposed in this work to systematically investigate the temporal and spatial evolution of galvanic corrosion of the Mg-steel couple with the growing anisotropic deposition layer.By utilizing the multi-physics field coupled technique,various coupled physical-chemical processes underlying the corrosion behavior are built into the model,including chemical reactions,ionic mass transfer in the bulk solution and the deposition layer,interfacial reaction,deposition of corrosion products as well as the morphological transitions caused by metal dissolution and deposition.In particular,the anisotropic deposit film is considered to be a porous layer with a porosity varying in time and space as the corrosion evolves.The predicted corrosion morphology by this model is better than the previous models.The coupled relationship between the electrochemical behavior(e.g.,electrode reaction kinetics,current density,surface potential)and the physical processes(e.g.,ionic transport,geometric evolution of metal surface and film interface)is revealed.The results indicate that a porous deposition layer with a denser inner layer and a loose outer layer is generated,leading to more significant inhibition of mass transfer in the inner layer than the outer layer.The anisotropism of the deposition layer results in a non-uniform conductivity distribution and a discontinuous current density distribution in the electrolyte.The current density on the electrode surface is inhibited by the deposition layer and the variation in the cathode/anode area ratio during the corrosion process.The competition between the transport process and the electrochemical reaction determines the spatial-temporal evolution of the ion concentration.

居家脊柱专项运动在胸椎后凸老年人中应用的可行性研究

目的 评估不同运动习惯的中国老年人进行居家脊柱后凸专项运动的可行性,探讨该运动计划对减少胸椎后凸角度和改善活动能力的效果.方法 本研究采用单组前后对照研究设计.在中国武汉市4个社区选取20名年龄≥60岁,患有胸椎过度后凸畸形且有康复潜力的老年人为研究对象.老年人接受为期6周的居家脊柱后凸专项运动干预,包括热身、肌肉加强、脊柱直立、脊柱灵活性和放松5个部分(22个动作),共有7次1 h的小组课程和35次的居家练习.在干预前后对老年人两种站立姿势下胸椎后凸角度、静态平衡、动态平衡、心肺功能、功能步态、疼痛及自我形象等指标进行评估并比较.采用老年人小组课程的出勤率、居家练习依从性及参与评价等指标来分析干预的可行性.结果 所有老年人均完成了小组课程和>75%的居家练习内容.干预后老年人在放松和最佳站立姿势下胸椎后凸角度较干预前均减少,中位数及四分位数间距分别 为-12.0°(-15.5°,-4.0°)(Z=-3.98,P<0.001)和-10.0°(-14.0°,-5.3°)(Z=-3.79,P<0.001).此外,干预后老年人疼痛程度明显减轻(P<0.001),自我形象认知得分提高(P<0.001),5项活动能力水平也有所提高(P<0.01).干预前后凸严重程度和日常体力活动强度不影响干预效果.大多数老年人认为干预强度适中且令人满意.结论 居家脊柱后凸专项运动在老年人胸椎过度后凸干预中具有可行性,并且可减少胸椎后凸角度,提升活动能力.

GENERATION OF TRANSGENIC MICE FOR IN VIVO DETECTION OF INSULIN-CONTAINING GRANULE EXOCYTOSIS AND QUANTIFICATION OF INSULIN SECRETION

Insulin secretion is a complex and highly regulated process.Although much progress has been made in understanding the cellular mechanisms of insulin secretion and regulation,it remains unclear how conclusions from these studies apply to living animals.That few studies have been done to address these issues is largely due to the lack of suitable tools in detecting secretory events at high spatial and temporal resolution in vivo.When combined with genetically encoded biosensor,optical imaging is a powerful tool for visualization of molecular events in vivo.In this study,we generated a DNA construct encoding a secretory granule resident protein that is linked with two spectrally separate fluorescent proteins,a highly pH-sensitive green pHluorin on the intra-granular side and a red mCherry in the cytosol.Upon exocytosis of secretory granules,the dim pHluorin inside the acidic secretory granules became highly fluorescent outside the cells at neutral pH,while mCherry fluorescence remained constant in the process,thus allowing ratiometric quantification of insulin secretory events.Furthermore,mCherry fluorescence enabled tracking the movement of secretory granules in living cells.We validated this approach in insulin-secreting cells,and generated a transgenic mouse line expressing the optical sensor specifically in pancreaticβ-cells.The transgenic mice will be a useful tool for future investigations of molecular mechanism of insulin secretion in vitro and in vivo.

Superior Slurry Erosion Behavior of a Casting NiCoCrFeNb0.45 Eutectic High Entropy Alloy

The flow passage components in hydraulic machinery will be eroded rapidly when running in sand water.The wear resistance of materials commonly used in hydraulic machinery needs to be improved to prevent the failure of hydraulic machinery.New wear-resistant materials are urgently needed to improve the service life of hydraulic machinery.Eutectic high entropy alloy(EHEA)is a new kind of alloys with in situ lamellar structure.NiCoCrFeNb0.45 EHEA has combined excellent strength and toughness.In this study,slurry erosion tests of NiCoCrFeNb0.45 EHEA were carried out with different impact angles and impact velocities using a rotary jet erosion test apparatus.The NiCoCrFeNb0.45EHEA exhibited significant slurry erosion resistance compared with medium carbon steel 1045 and stainless steel 04 Cr13 Ni5 Mo.The erosion rate of EHEA is much slower.Compared with medium carbon steel and stainless steel,the erosion of EHEA is completed via the accumulation and removal of platelets after plowing and work hardening,accompanied by partial micro-cutting.

Comparison of caspase-3 activation in tumor cells upon treatment of chemotherapeutic drugs using capillary electrophoresis

Caspases play important roles in cell apoptosis.Meas-urement of the dynamics of caspase activation in tumor cells not only facilitates understanding of the molecular mechanisms of apoptosis but also contributes to the development,screening,and evaluation of anticancer drugs that target apoptotic pathways.The fluorescence resonance energy transfer(FRET)technique provides a valuable approach for defining the dynamics of apop-tosis with high spatio-temporal resolution.However,FRET generally functions in the single-cell level and becomes ineffective when applied in the high throughput detection of caspase activation.In the cur-rent study,a FRET sensor was combined with capillary electrophoresis(CE)to achieve a high throughput method for cellular caspase detection.The FRET-based CE system is composed of a homemade CE system and a laser source for detecting the dynamics of caspase-3 in various cells expressing sensors of caspase-3 that have been treated with anticancer drugs,such as cell cycle-independent drug cisplatin and specific cell cycle drugs camptothecin and etoposide,as well as their combination with tumor necrosis factor(TNF).A posi-tive correlation between the caspase-3 activation ve-locity and drug concentration was observed when the cells were treated with cisplatin,but cells induced by camptothecin and etoposide did not show any apparent correlation with their concentrations.Moreover,differ-ent types of cells presented distinct sensitivities under the same drug treatment,and the combination treat-ment of TNF and anticancer drugs significantly accel-erated the caspase-3 activation process.Its high throughput capability and detection sensitivity make the FRET-based CE system a useful tool for investi-gating the mechanisms of anticancer drugs and anti-cancer drug screening.

Erosion Behavior of NiCoCrFeNb_(0.45) Eutectic High-Entropy Alloy in Liquid-Solid Two-Phase Flow

The metal components exposed to the high-velocity liquid-solid flow can be rapidly eroded by the accelerated particles.With an excellent combination of strength and toughness,the NiCoCrFeNb_(0.45)eutectic high-entropy alloy(EHEA)has emerged as a promising material to resist erosion damage.In this study,the erosion behavior of NiCoCrFeNb_(0.45)EHEA in high-velocity multiphase flow is investigated through the coupling analysis of material properties,multiphase flow,and particle–surface impact behavior.The inherent mathematical relationship is discovered between the erosion rates and the impact velocity,impact angle,and test time.The results show that the NiCoCrFeNb_(0.45)EHEA has superior erosion resistance than the commonly used machinery materials.The principal material removal mechanism is the formation and brittle fracture of the platelets,accompanied by micro-cutting and ploughing at some oblique angles.The higher work-hardenability of NiCoCrFeNb_(0.45)EHEA could mitigate the erosion damage as time proceeds,and this effect becomes more apparent as the impact angle increases.Therefore,the evolution of erosion damage with time varies significantly depending on the impact angle.Based on the test data and computational fluid dynamics(CFD)modeling of the near-wall flow field,a power exponential function relationship between erosion depth and the corresponding impact velocity at various locations on the material surface is established.