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Arctic sea-ice extent: No record minimum in 2023 or recent years

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola m.Johannessen Tor I.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. In general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic minimum ice Climate

钢厂煤气管道新型涂料的制备及其防腐蚀防结垢机理

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涂料工业 2025年第3期55卷 62-68页

作者：彭程龙红明汪磊宝武集团环境资源科技有限公司上海201900 安徽工业大学冶金工程学院安徽马鞍山243032 同济大学机械与能源工程学院上海201900

针对钢厂煤气管道使用过程存在内壁腐蚀和黏结粉尘问题,以气相二氧化硅、碳化硅、胶体石墨、鳞片石墨烯和有机硅聚合物改性液体树脂为原料,采用溶胶-凝胶法制备了有机硅聚合物改性液体树脂-无机填料复合涂料,研究了涂层的润湿性、机械... 详细信息

针对钢厂煤气管道使用过程存在内壁腐蚀和黏结粉尘问题,以气相二氧化硅、碳化硅、胶体石墨、鳞片石墨烯和有机硅聚合物改性液体树脂为原料,采用溶胶-凝胶法制备了有机硅聚合物改性液体树脂-无机填料复合涂料,研究了涂层的润湿性、机械强度、防腐蚀和防结垢性能。结果表明:涂层具有良好的疏水性,表面能为25.91 mJ/m^(2),相比碳钢降低了41.58%,水接触角为120.1°;附着力1级且几乎不受温度变化的影响;经砂纸磨损后,涂层的水接触角仍大于105°,展现出良好的耐磨性;在硫酸、盐酸和氯化钠溶液中的最大腐蚀速率分别为12.36 mg(/cm^(2)∙h)、9.89 mg(/cm^(2)∙h)和2.55 mg(/cm^(2)·h),相比碳钢分别降低了73%、74%和83%;同时,涂层能有效抑制NH4Cl的结晶黏结。在工业现场煤气管道中进行连续5个月防腐蚀和防结垢性能应用测试,相比普通碳钢,涂装涂料的管道表面没有出现明显的腐蚀与结垢行为。气相二氧化硅分子在涂层表面形成了具有疏水性的微纳米结构,填料之间相互重叠形成了类似“迷宫”的结构,以及胶体石墨与碳化硅的协同作用是该涂料表现出优异的防腐蚀防结垢性能的机理。

关键词：煤气管道涂料防腐蚀防结垢应用测试

Perspectives for the association between olfactory disturbances and depression in Parkinson's disease

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Neural Regeneration Research 2019年第4期14卷 591-592页

作者： jessica L.Ilkiw marcelo m.S.Lima Neurophysiology Laboratory Department of PhysiologyFederal University of Paraná

Non-motor disturbances in Parkinson’s disease:Globally,population aged 60 or over is growing and considering the World Bank predictions for the next 20 years it is expected that the number of Parkinson’s disease(PD)cases will double at the end of this period thus,reaching an impressive 13–39 million patients *** scenario is potentially associated with a significant global negative impact on public health systems particularly in countries with increased ageing populations such as the European countries,Asia and *** pathophysiology of PD involves the progressive degeneration of dopaminergic neurons of the substantia nigra pars compacta(SNpc)that triggers denervation of the nigrostriatal pathway and consequent significant reduction of dopamine in the dorsal *** process leads to a critical motor impairment scenario characterized by bradykinesia,rigidity,resting tremor,and postural instability(Emamzadeh and Surguchov,2018).However,several other non-motor disturbances develop earlier,thus,being considered as prodromal signs of the *** this sense,the literature is increasingly emphasizing the importance of investigating mood and olfactory disruptions as high sensitive benchmarks of the early-phase *** fact,the need for innovative early-phase diagnostic tools,as well as the elucidation of the pathophysiological mechanisms of such disturbances,is essential priority in the field of investigation of ***,in the year of 2015,a woman was known for an intriguing ability of“smell PD”.Her husband had lived with the disease for twenty years and during this process she noticed that his odor slowly changed to a musky ***,this woman could associate this particular smell with PD after meeting different people with this distinct odor in a charity for PD *** fact,this clever observation is aligned with studies showing that hyposmia is found decades before the motor *** type of anecdotal story,

关键词： Parkinson olfactory disturbances association

Comparison of closure measurements with finite element model results in an underground coal mine in central Utah

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International Journal of mining Science and Technology 2019年第1期29卷 9-15页

作者： William G.Pariseau michael K.mcCarter jessica m.Wempen Department of mining Engineering University of Utah

Quantitative analysis of mine-wide subsidence at the kilometer scale and details of stress distribution about an advancing longwall face are estimated using an adaptation of the finite element method. The method is well suited to the tasks at hand. For greater realism, variability of strata properties is taken into account as are the effects of joints and cleats on elastic moduli and strengths. Evolution of pillar stress and entry closure remote from the face is readily quantified in a series of analyses that simulate face advance. Computed results compare favorably with the evolution of closure measurements about an instrumented pillar in a two-entry headgate. The appropriateness of the finite element method is confirmed. This method is based on first principles that avoid empirical schemes of uncertain applicability and numerical models ‘‘calibrated" by fitting computer output to mine measurements.

关键词： Finite element modeling longwall mining mine subsidence Stress modeling

multi-agent Control of High Redundancy Actuation

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International Journal of Automation and computing 2014年第1期11卷 1-9页

作者： jessica Davies Roger Dixon Roger m.Goodall Thomas Stefen Lancaster Environment Centre Lancaster University School of Electrical Electronic & Systems EngineeringLoughborough University Department of Aeronautical and Automotive Engineering Loughborough University

The high redundancy actuator(HRA)concept is a novel approach to fault tolerant actuation that uses a high number of small actuation elements,assembled in series and parallel in order to form a single actuator which has intrinsic fault *** this structure afords resilience under passive control methods alone,active control approaches are likely to provide higher levels of performance.A multiple-model control scheme for an HRA applied through the framework of multi-agent control is presented *** application of this approach to a 10×10 HRA is discussed and consideration of reconfguration delays and fault detection errors are *** example shows that multi-agent control can provide tangible performance improvements and increase fault tolerance in comparison to a passive fault tolerant *** delays are shown to be tolerable,and a strategy for handling false fault detections is detailed.

关键词： Fault tolerance actuators intelligent control redundancy intelligent actuators cooperative systems

CTP Synthase Is Required for Optic Lobe Homeostasis in Drosophila

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Journal of Genetics and Genomics 2015年第5期42卷 261-274页

作者： Ömür Y.Tastan Ji-long Liu medical Research Council Functional Genomics Unit Department of PhysiologyAnatomy and GeneticsUniversity of Oxford

CTP synthase （CTPsyn） is a metabolic enzyme responsible for the de novo synthesis of the nucleotide CTE Several recent studies have shown that CTPsyn forms filamentous subcellular structures known as cytoophidia in bacteria, yeast, fruit flies and humans. However, it remains elusive whether and how CTPsyn and cytoophidia play a role during development. Here, we show that cytoophidia are abundant in the neuroepithelial stem cells in Drosophila optic lobes. Optic lobes are underdeveloped in CTPsyn mutants as well as in CTPsyn RNAi. moreover, overexpressing CTPsyn impairs the development of optic lobes, specifically by blocking the transition from neuro- epithelium to neuroblast. Taken together, our results indicate that CTPsyn is critical for optic lobe homeostasis in Drosophila.

关键词： CTP synthase Cytoophidium Drosophila Central nervous system Neuroepithelial stem cell

Removal and desorption of chromium in synthetic effluent by a mixed culture in a bioreactor with a magnetic field

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Journal of Environmental Sciences 2020年第5期32卷 151-159页

作者： Roseli mDias jessica GSilva Vicelma LCardoso miriam mde Resende Faculty of Civil Engineering Federal University of UberlandiaMinas GeraisBrazil Faculty of Chemical Engineering Federal University of UberlandiaMinas GeraisBrazil

Two chromium removal experiments were performed in bioreactors with and without a magnetic field under the same *** release of the chromium present in the biomass was tested in two experiments one with the initial pH of the medium and one with pH *** objective was to remove Cr(Ⅵ)and total Cr from the effluent,this was carried out by placing biological treatments of synthetic effluent contaminated with 100 mg/L of Cr(Ⅵ)in a bioreactor with neodymium magnets that applied a magnetic field(intensity85.4 mT)to the mixed *** removal of Cr(Ⅵ)was approximately 100.0%for the bioreactor with a magnetic field and 93,3%for the bioreactor without a magnetic field for9 hr of recirculation of the synthetic effluent by the *** removal of total Cr was61.6%and 48.4%,with and without a magnetic field,respectively;for 24 *** desorption of Cr(VI)in the synthetic effluent was 0.05 mg/L,which is below the limit established by Brazilian legislation(0.1 mg/L)for the discharge of effluent containing Cr(Ⅵ)into bodies of *** results obtained for the removal of chromium in synthetic effluent suggested that there was no significant influence on the viable cell count of the mixed *** desorption of Cr(Ⅵ)in synthetic effluent after bioadsorption of chromium by the mixed culture in the process of removal of chromium in bioreactors with and without a magnetic field was not significant in either of the experiments with different initial pHs.

关键词： Chromium removal mixed culture magnetic field Desorption Effluent treatment

煤裂隙粗糙度和开度对注水渗流影响的实验研究

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煤田地质与勘探 2025年第1期53卷 92-101页

作者：王刚陈雪畅陈昊隆清明刘义鑫山东科技大学矿山灾害预防控制国家重点实验室培育基地山东青岛266590 山东科技大学安全与环境工程学院山东青岛266590 中煤科工集团重庆研究院有限公司瓦斯灾害监控与应急技术国家重点实验室重庆400039

【目的】煤层注水是矿井除尘、防治煤与瓦斯突出和冲击地压等灾害的关键技术措施,而裂隙粗糙度、开度等形态特征对煤层注水效果具有显著影响。【方法】借助砂纸和聚酰亚胺高温胶带制备了含有不同粗糙度和开度裂隙的煤样,利用激光光谱共... 详细信息

【目的】煤层注水是矿井除尘、防治煤与瓦斯突出和冲击地压等灾害的关键技术措施,而裂隙粗糙度、开度等形态特征对煤层注水效果具有显著影响。【方法】借助砂纸和聚酰亚胺高温胶带制备了含有不同粗糙度和开度裂隙的煤样,利用激光光谱共聚焦显微镜精准计算裂隙粗糙度参数,测试裂隙煤样渗流量。【结果和结论】结果表明,表面高度偏差Ha、表面最大高度Hz和三维形貌分形维数Ds可以作为表征煤剖面粗糙程度的参数。煤体渗流量随Ha、Hz和Ds的升高呈指数降低趋势,随着剖面粗糙度从4.69提高到18.43,裂隙内的渗流量最高下降84.42%。裂隙开度在60~90μm时其粗糙度对渗流的阻碍效果达到最高,此后粗糙单元阻碍效果开始减弱,裂隙开度在渗流过程占据主导作用。煤体渗流量随裂隙开度的升高呈指数升高的趋势,裂隙开度由30μm提高到150μm,裂隙渗流量最高可增大355.88倍。通过对裂隙开度和粗糙度与渗流量关系的深入探究,明确了两者在煤层注水过程中的关键作用机制,强调在煤层注水实践中应充分考虑裂隙形态特征,依据不同的裂隙开度和粗糙度情况合理选择注水方式,以实现煤层注水效果的有效提升。

关键词：煤裂隙开度裂隙粗糙度裂隙粗糙度表征渗流量矿井除尘

Stress Intensity Factor for the Interaction between a Straight Crack and a Curved Crack in Plane Elasticity

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Acta mechanica Solida Sinica 2016年第4期29卷 407-415页

作者： m.R.Aridi N.m.A.Nik long Z.K.Eshkuvatov Institute for mathematical Research Universiti Putra Malaysia College of Foundation and General Studies Universiti Tenaga Nasional mathematics Department Faculty of Science Universiti Putra Malaysia

Formulation in terms of hypersingular integral equations for the interaction between straight and curved cracks in plane elasticity is obtained using the complex variable functions method. The curved length coordinate method and a suitable numerical scheme are used to solve such integrals numerically for the unknown function, which are later used to find the stress intensity factor, SIF.

关键词： hypersingular integral equation complex variable function method curved length coordinate method stress intensity factor