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Effect of overheating-induced minor addition on Zr-based metallic glasses
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作者 杨福 薄振兴 +7 位作者 黄瑶 王雨田 孙博阳 鲁振 孙保安 柳延辉 汪卫华 潘明祥 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期118-125,共8页
Melt treatment is well known to have an important influence on the properties of metallic glasses(MGs).However,for the MGs quenched from different melt temperatures with a quartz tube,the underlying physical origin re... Melt treatment is well known to have an important influence on the properties of metallic glasses(MGs).However,for the MGs quenched from different melt temperatures with a quartz tube,the underlying physical origin responsible for the variation of properties remains poorly understood.In the present work,we systematically studied the influence of melt treatment on the thermal properties of a Zr50Cu36Al14 glass-forming alloy and unveiled the microscopic origins.Specifically,we quenched the melt at different temperatures ranging from 1.1Tl to 1.5Tl(Tl is the liquidus temperature)to obtain melt-spun MG ribbons and investigated the variation of thermal properties of the MGs upon heating.We found that glass transition temperature,Tg,increases by as much as 36 K,and the supercooled liquid region disappears in the curve of differential scanning calorimetry when the melt is quenched at a high temperature up to 1.5Tl.The careful chemical analyses indicate that the change in glass transition behavior originates from the incorporation of oxygen and silicon in the molten alloys.The incorporated oxygen and silicon can both enhance the interactions between atoms,which renders the cooperative rearrangements of atoms difficult,and thus enhances the kinetic stability of the MGs. 展开更多
关键词 metallic glass thermal properties melt treatment overheating oxygen content
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Life Origin in the Milky Way Galaxy: III. Spatial Distribution of Overheated Stars in the Solar Neighborhood
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作者 Alexander N. Safronov 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期693-709,共17页
A concept of ensemble averaged stellar reactors is developed to study the dynamics of processes occurring in stars, allocated in the ~200 pc solar neighborhood. According to the effective temperature value, four stell... A concept of ensemble averaged stellar reactors is developed to study the dynamics of processes occurring in stars, allocated in the ~200 pc solar neighborhood. According to the effective temperature value, four stellar classes are identified, for which the correlation coefficients and standard deviation are counted. The theory of the buoyancy terrestial elements is generalized to stellar systems. It was suggested that stars are over-heated due to the shift parameters of the nuclear processes occurring inside the stars, which leads to the synthesis of transuranium elements until the achievement of a critical nuclear mass and star explosion. The heavy transuranium elements sink downward and are concentrated in the stellar depth layers. The physical explanation of the existence of the critical Chandrasekhar star limit has been offered. Based on the spatial analysis of overheated stars, it was suggested that the withdrawal of the stellar reactor from the equilibrium state is a consequence of extragalactic compression inside the galaxy arm due to the arm spirality (not to be confused with the spirality of the galaxy itself). 展开更多
关键词 Stellar Nucleogenesis Ensemble-Averaged Stellar Reactor overheated Stars Chandrasekhar Stellar Limit Arm Spirality
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Effects of melt overheating degree on undercooling degree and amorphous forming of Nd_9Fe_(85-x)Ti_4C_2B_x(x=10, 12) magnetic alloys
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作者 杨梦琳 潘晶 +2 位作者 刘新才 肖晓燕 詹玉勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第10期2633-2640,共8页
The effectsof melt overheating degree on the undercooling degree and resultant solidification structures of Nd9Fe85-xTi4C2Bx(x=10, 12) glass-forming alloyswerestudied by differential thermal analysis combining with ... The effectsof melt overheating degree on the undercooling degree and resultant solidification structures of Nd9Fe85-xTi4C2Bx(x=10, 12) glass-forming alloyswerestudied by differential thermal analysis combining with solidification structure analysis. The results indicate that the undercooling degree of Nd9Fe85-xTi4C2Bx(x=10, 12) alloys significantly increaseswith the rise of melt overheating degree, and two overheating degree thresholds corresponding to the drastic increase of the mean undercooling degree are found for each of the alloys. The existence of two turning points of the mean undercooling degreescan be linked to the structure transitions inside the overheated melts, which result in the evident increase of volume fraction of amorphous phasein the solidified structures. 展开更多
关键词 magnetic alloy melt overheating undercoolingdegree structure transition glass formability
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Overheating temperature of 7B04 high strength aluminum alloy 被引量:5
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作者 高凤华 李念奎 +3 位作者 田妮 孙强 刘显东 赵刚 《中国有色金属学会会刊:英文版》 EI CSCD 2008年第2期321-326,共6页
The microstructure and overheating characteristics of the direct chill semicontinuous casting ingot of 7B04 high strength aluminum alloy,and those after industrial homogenization treatment and multi-stage homogenizati... The microstructure and overheating characteristics of the direct chill semicontinuous casting ingot of 7B04 high strength aluminum alloy,and those after industrial homogenization treatment and multi-stage homogenization treatments,were studied by differential scanning calorimetry(DSC),optical microscopy(OM)and scanning electron microscopy with energy dispersive X-ray spectroscopy(SEM-EDX).The results show that the microstructure of direct chill semicontinuous casting ingot of the 7B04 alloy contains a large number of constituents in the form of dendritic networks that consist of nonequilibrium eutectic and Fe-containing phases.The nonequilibrium eutectic contains Al,Zn,Mg and Cu,and the Fe-containing phases include two kinds of phases,one containing Al,Fe,Mn and Cu,and the other having Al,Fe,Mn,Cr,Si and Cu.The melting point of the nonequilibrium eutectic is 478℃for the casting ingot of the 7B04 alloy which is usually considered as its overheating temperature.During industrial homogenization treatment processing at 470℃,the nonequilibrium eutectic dissolves into the matrix of this alloy partly,and the remainder transforms into Al2CuMg phase that cannot be dissolved into the matrix at that temperature completely.The melting point of the Al2CuMg phase which can dissolve into the matrix completely by slow heating is about 490℃.The overheating temperature of this high strength aluminum alloy can rise to 500?520℃.By means of special multi-stage homogenization,the temperature of the homogenization treatment of the ingot of the 7B04 high strength aluminum alloy can reach 500℃without overheating. 展开更多
关键词 过热技术 温度 铝合金 氧化物
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The Resuming Insulation Discharge Failure and Conductor Overheating Failure Judgment Method of SF6 Electrical Equipment
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作者 Xiansheng ZHUANG Zhi LI Chengji HUANG 《Energy and Power Engineering》 2009年第2期122-127,共6页
Through the long time track examination and disintegration to SF6 circuit breaker, we obtain the massive monitor data and massive pictures. The criteria of resuming insulation discharge failure conforming to CSO2/CH2S... Through the long time track examination and disintegration to SF6 circuit breaker, we obtain the massive monitor data and massive pictures. The criteria of resuming insulation discharge failure conforming to CSO2/CH2S>7, is quite broad to SO2 and the H2S concentration permission. Even if it reaches 100μL/L, it will not be in danger immediately to the safe operation of equipment. We may plan, arrange, and overhaul calmly. When obtaining the bare conductor overheating failure, it has not involved the resuming insulation. We may use the resuming insulation discharge failure criterion. 展开更多
关键词 SF6 conductor DISCHARGE overheated FAILURE METHOD
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Investigation of the interaction of material of fuel cladding for WWER-1000 reactor with steam at a temperature of accident overheatings
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作者 Nadezhda Ishchenko Ivan Petelguzov Olena Slabospitska 《Materials Engineering Research》 2019年第2期32-39,共8页
The subject of this study is the oxidation of fuel rod cladding made of material Zr1Nb(0.1% O) in steam at temperatures in the range of 660℃ to 1200℃ with a surface in the initial state (after manufacturing - grindi... The subject of this study is the oxidation of fuel rod cladding made of material Zr1Nb(0.1% O) in steam at temperatures in the range of 660℃ to 1200℃ with a surface in the initial state (after manufacturing - grinding) and after additional chemical etching. The changes in the microstructure of tubes due to the interaction with steam were investigated. A comparison was made between the oxidation rate of this material (weight gain) and the data on the oxidation of other alloys for nuclear power plants. The oxidation rate of Zr1Nb(0.1% O) is close to the oxidation rate of other zirconium alloys. It is shown that after chemical treatment of the surface of the samples there is a more even growth of oxide films, and they have a smaller thickness for the same time of exposure than after mechanical grinding. Surface treatment before oxidation also affects the change of microstructure of samples when heated to high temperatures. 展开更多
关键词 high-temperature oxidation nuclear power plants ZIRCONIUM tubes fuel rod CLADDING STEAM surface treatment alloy and oxide structure ACCIDENT overheating
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Great change,big attraction and high expectation Persistent overheating of ITMA ASIA +CITME 2018 registration
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《China Textile》 2018年第1期42-45,共4页
On June 19th,2017,the registration system of ITMA ASIA+CITME 2018 came online officially.In the past five months,the exhibition recruitment work has obtained the general concentration of the industry.What is the bigg... On June 19th,2017,the registration system of ITMA ASIA+CITME 2018 came online officially.In the past five months,the exhibition recruitment work has obtained the general concentration of the industry.What is the biggest difference of this exhibition with the previous ones?What will the audiences and exhibitors get from this exhibition? 展开更多
关键词 Great change big attraction and high expectation Persistent overheating of ITMA ASIA
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Results of Treatment of Patients with COVID-19 and the Role of Cooling and Overheating in the Development of Viral Respiratory Infections
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作者 Isma Gašanin 《Journal of Pharmacy and Pharmacology》 2022年第11期299-312,共14页
During the Covid-19 pandemic in Serbia on March 6.to 03.04.2020.I cured 41 cases with a very severe clinical picture of influenza or possibly Covid-19.At that time,the Health Center in Sjenica did not have the materia... During the Covid-19 pandemic in Serbia on March 6.to 03.04.2020.I cured 41 cases with a very severe clinical picture of influenza or possibly Covid-19.At that time,the Health Center in Sjenica did not have the material for the diagnosis of Covid-19,and the patients refused to go to the neighboring Health Center because of the fear that caused sudden deaths.In my scientific work:“The role of cold in the origin and development of diseases with special review of some diseases of the respiratory system-treatment and prevention”,I proved the effect of cold and overheating on all organs and effective treatment.Under the effect of cooling,vasoconstriction,impaired circulation and impaired metabolism occur.Macrophage motility is reduced,phagocytes are weakened,ingestion,which causes easy implantation of the virus in the lungs.All the viral infections I followed for more than 35 years passed with mild symptoms if there was no previous cold or during the illness,even with the highly infectious Mexican flu(A/H1N1)and influenza.Patients with Covid-19 reported minimal,minor or more intense colds,which also determined the severity of the clinical picture. 展开更多
关键词 Distance mask disinfection vaccine prevention“without cooling and overheating”of the organism-respiratory tract proper use of corticosteroids-gradual abolition prevention of obesity adequate physical activity
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熔体过热度对Zr基非晶合金力学性能和热稳定性的影响
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作者 张香云 张博循 +1 位作者 肖才云 袁子洲 《有色金属(冶炼部分)》 CAS 北大核心 2024年第3期103-107,共5页
采用吸铸法制备Zr_(70)Cu_(13.5)Ni_(8.5)Al_(8)非晶合金,采用同步差示扫描量热仪(DSC)和万能试验机对非晶合金显微结构进行表征和力学性能测试,并利用XRD和SEM对试样的相组成和剪切带观察。研究发现:随着吸铸功率增加,热稳定性、玻璃... 采用吸铸法制备Zr_(70)Cu_(13.5)Ni_(8.5)Al_(8)非晶合金,采用同步差示扫描量热仪(DSC)和万能试验机对非晶合金显微结构进行表征和力学性能测试,并利用XRD和SEM对试样的相组成和剪切带观察。研究发现:随着吸铸功率增加,热稳定性、玻璃形成能力不断提高;Zr_(70)Cu_(13.5)Ni_(8.5)Al_(8)非晶合金的锯齿流变现象越明显,综合力学性能越好,其中吸铸功率8 kW时,试样的屈服强度、抗压强度和塑性达到最值,室温综合力学性能最好,且剪切带分布情况最好,但是继续提高吸铸功率,力学性能反而变差。 展开更多
关键词 过热度 金属玻璃 显微组织 玻璃形成能力
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基于恒流式热线风速仪的流速检测实训台设计
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作者 苏燕 周恒超 《山东商业职业技术学院学报》 2024年第4期122-125,共4页
基于恒流式热线风速仪设计了可实现复杂表面的气流测量和湍流结构分析的流速检测实训台。实训台在基于单片机的硬件电路上创新设计,保证了较高的测量精度。可用于相关专业的教科研,同时也可用于学生自制热线式风速探针的校准,提高学生... 基于恒流式热线风速仪设计了可实现复杂表面的气流测量和湍流结构分析的流速检测实训台。实训台在基于单片机的硬件电路上创新设计,保证了较高的测量精度。可用于相关专业的教科研,同时也可用于学生自制热线式风速探针的校准,提高学生的动手操作能力,培养学生的学习兴趣。 展开更多
关键词 恒流式 流速检测 过热比 IPS触摸屏
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8 kA稀土电解槽单侧电导及阴极优化数值模拟
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作者 龚姚腾 吕招东 +1 位作者 陈泽斌 逄启寿 《中国有色冶金》 CAS 北大核心 2024年第3期64-71,共8页
稀土电解槽导电板的分布位置对稀土电解槽的物理场会有影响,为探究稀土电解槽中导电板分布的最优位置,在本次仿真实验中为该导电板的分布引入一个等差数列的分布梯度,通过对不同分布梯度下的槽内物理场仿真数值进行比较,进而得到稀土电... 稀土电解槽导电板的分布位置对稀土电解槽的物理场会有影响,为探究稀土电解槽中导电板分布的最优位置,在本次仿真实验中为该导电板的分布引入一个等差数列的分布梯度,通过对不同分布梯度下的槽内物理场仿真数值进行比较,进而得到稀土电解槽导电板最优分布模型。在仿真过程中观察到阴极底部的尖角对实验结果影响较大,在其他条件保持不变的基础上将阴极底部由圆柱优化为半球形,通过与未优化的结构进行对比,验证新型电解槽结构的合理性。仿真结果显示:随着导电板由侧边位置向中间偏移,电解反应时槽内的温度与阳极电势基本保持不变,槽盖板与阳极间的电势差逐渐减小,槽内电流密度缓慢增大。当将阴极钼棒底部由柱状结构改为球状结构后,槽内电势分布更为均匀,电流密度相较于之前的结构也有所增加,优化后的结构能改善局部过热问题,同时也使得电解效率增大。 展开更多
关键词 稀土电解槽 单侧导电板 通电位置 阴极底部结构 物理场模拟 结构优化 局部过热 电解效率
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计及制冷系统和过热保护的含高温超导电缆配电网可靠性评估方法
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作者 吕忠麟 顾洁 金之俭 《电力自动化设备》 EI CSCD 北大核心 2024年第1期64-72,共9页
为适应高温超导电缆商业化运行需求,提出一种考虑不同应用模式下制冷系统和过热保护影响的含高温超导电缆的配电网可靠性评估方法。依据高温超导电缆制冷系统的工作原理、故障特性及过热保护装置的动作逻辑和自动重合规则,对高温超导电... 为适应高温超导电缆商业化运行需求,提出一种考虑不同应用模式下制冷系统和过热保护影响的含高温超导电缆的配电网可靠性评估方法。依据高温超导电缆制冷系统的工作原理、故障特性及过热保护装置的动作逻辑和自动重合规则,对高温超导电缆系统可靠性进行建模分析。考虑了低压联络和配电线路增效2种典型应用模式下高温超导电缆接入对配电网的可靠性影响,采用融入了计及高温超导电缆的新增故障模式的最小割集法求解配电网可靠性指标,实现含高温超导电缆的配电网可靠性评估。以某实际配电网为算例,通过仿真分析了制冷系统故障和过热保护对配电网不同可靠性指标的影响,并与传统的配电网改造方案进行对比,验证了所提方法的有效性。 展开更多
关键词 高温超导电缆 配电网 可靠性评估 最小割集法 制冷系统 过热保护
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低温慢烫对淘汰蛋鸡去羽效果及胸肉过熟的影响
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作者 史家浩 徐幸莲 +6 位作者 朱纯 刘岳龙 李建超 黄祖芬 徐梦泽 刘磊 王鹏 《食品工业科技》 CAS 北大核心 2024年第17期40-47,共8页
本研究目的在于通过调整浸烫参数的方式减少淘汰蛋鸡在屠宰加工中的损失。以饲养日龄为400 d的淘汰蛋鸡作为研究对象,探究不同浸烫方式对其羽毛去除效果及皮下肌肉过熟程度的影响。分别设置三种温度和时间的浸烫组合:65℃-3 min(高温浸... 本研究目的在于通过调整浸烫参数的方式减少淘汰蛋鸡在屠宰加工中的损失。以饲养日龄为400 d的淘汰蛋鸡作为研究对象,探究不同浸烫方式对其羽毛去除效果及皮下肌肉过熟程度的影响。分别设置三种温度和时间的浸烫组合:65℃-3 min(高温浸烫,High Temperature Scald,HS)、60℃-4 min 20 s(中温慢烫,Middle Temperature Slow Scald,MSS)、58℃-4 min 20 s(低温慢烫,Low Temperature Slow Scald,LSS),并以未经浸烫的淘汰蛋鸡作为对照组。通过测定浸烫后去羽力(Feather Retention Force,FRF)及计数残留羽毛数量表征浸烫脱毛效果。通过测定肉色、测量过熟区域深度、DSC扫描、拉曼光谱扫描表征不同浸烫处理对皮下肌肉过熟程度。浸烫后淘汰蛋鸡HS组与LSS组羽毛去除效果无显著差异,MSS组去羽力与残留羽毛数量显著低于另外两处理组(P<0.05),两种残留羽毛计数结果显示采用长时间浸烫能够使毛根数量减少。浸烫后鸡胸肉L*值显著高于对照组(P<0.05),其中HS组L*值比LSS、MSS组分别显著高出5.33与4.75(P<0.05)。沿肌纤维方向切割鸡胸肉发现截面出现明显分层(白色肉与正常肉),HS组白色肉厚度相比LSS组与MSS显著增加。DSC结果显示虽然三种浸烫处理均会使淘汰蛋鸡胸肉肌球蛋白变性,但是HS组胸肉中肌浆蛋白或胶原蛋白以及肌动蛋白的变性程度均高于其他两处理组。蛋白质二级结构相对含量显示HS组胸肉蛋白质变性程度最高。综合羽毛去除效果结果与胸肉过熟结果,得到淘汰蛋鸡最适浸烫参数为:60℃-4 min 20 s。本研究在抑制浸烫中皮下肌肉过熟程度的同时提升了浸烫脱毛效果,为企业屠宰淘汰蛋鸡提供技术参考。 展开更多
关键词 淘汰蛋鸡 低温慢烫 去羽效果 肌肉过熟 蛋白变性
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人类世人类学的可持续性 被引量:1
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作者 托马斯·许兰德·埃里克森 卞思梅(译) 彭文斌(校) 《云南师范大学学报(哲学社会科学版)》 北大核心 2024年第2期104-114,共11页
早期社会与文化人类学所研究的社会都被默认为我们现在所称的可持续性社会,因为它们被认为能够无限地复制自己,并且只会逐渐地,几乎难以被察觉地发生改变。变化也被认为是由外生因素引起的,如殖民主义。这与当代人类学实践和理论的对比... 早期社会与文化人类学所研究的社会都被默认为我们现在所称的可持续性社会,因为它们被认为能够无限地复制自己,并且只会逐渐地,几乎难以被察觉地发生改变。变化也被认为是由外生因素引起的,如殖民主义。这与当代人类学实践和理论的对比显著:人类世人类学将全球化当作一种事实,认为社会是相互联系的,文化是无界的,对可持续性的威胁主要是从生态破坏和气候变化的角度来概念化的。可持续发展的概念于1987年被提出,之后在联合国可持续发展目标中得到了详细阐述,其与当代人类学的全球视野一致,但以经济增长为前提,并将文化多样性纳入其中。对于这一论述及其相关实践,人类学正在做出重大贡献,它从一个世纪前取得的方法论进步中获益,将民族志置于全球人类世的背景中,用学科工具来批判轻率的普遍主义,与地方世界进行对话并呈现了许多替代性选择。虽然为研究表面不变的乡村社会而设计的方法论对研究全球危机仍具意义,但新人类学必然是跨学科的。 展开更多
关键词 人类世 过热 人类学史 民族志方法 可持续性
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GIS内触头过热的无线感知系统研制 被引量:1
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作者 李爽 鲁旭臣 +2 位作者 唐红 唐佳能 崔文军 《高压电器》 CAS CSCD 北大核心 2024年第5期31-38,45,共9页
为了实现72.5 kV及以上电压GIS内触头温度的无线感知,文中阐述了一套GIS内触头温度无线感知系统的设计思路,并进行了研制。通过功能性试验,验证了本系统的有效性和可行性。最后,建立了252 kV GIS角型隔离开关接触良好和接触不良工况模型... 为了实现72.5 kV及以上电压GIS内触头温度的无线感知,文中阐述了一套GIS内触头温度无线感知系统的设计思路,并进行了研制。通过功能性试验,验证了本系统的有效性和可行性。最后,建立了252 kV GIS角型隔离开关接触良好和接触不良工况模型,开展了一系列局部过热无线感知试验。试验数据与热电偶测试数据进行了对比,验证了本系统的可信性。试验结果表明:本系统能够实现GIS内部触头温度的无线感知;当接触电阻Rj>250μΩ,动触头及静触头座的温度上升较快;当Rj达到620μΩ,负荷电流600 A时,静触头座的温度已接近50℃,可勉强通过红外成像检出;当Rj达到1.8 mΩ,负荷电流大于400 A时,触头的温度一直在增长,可通过红外成像清晰检测。 展开更多
关键词 GIS内触头 无线感知 局部过热 红外成像 接触电阻
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基于物联网的电力变压器过热故障红外检测系统设计 被引量:1
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作者 温启良 文华 《电子设计工程》 2024年第1期68-72,共5页
电力变压器运行过程中容易受到自身因素和外界因素影响出现过热故障,进而发生事故,为此,该文基于物联网设计了一种新的电力变压器过热故障红外检测系统,在物联网技术的基础上对系统的硬件和软件进行开发设计。系统硬件主要设计了红外热... 电力变压器运行过程中容易受到自身因素和外界因素影响出现过热故障,进而发生事故,为此,该文基于物联网设计了一种新的电力变压器过热故障红外检测系统,在物联网技术的基础上对系统的硬件和软件进行开发设计。系统硬件主要设计了红外热像仪、中心控制计算机、监测云台三部分。红外摄像仪负责采集设备的实时温度数据,将数据发送到中心控制计算机;中心控制计算机负责收集并储存数据,同时将数据判断指令传达到云台;云台负责运行中心计算机的指令。通过数据采集、红外图像处理和温度测量与显示完成系统检测软件设计。实验结果表明,所设计系统能够同时绘制出温升曲线和三相曲线,更好地判定系统温度是否出现过热故障,与传统系统相比,预警响应时间平均值分别降低13.916 min和5.548 min,误检率平均值分别降低10.942%和8.262%。 展开更多
关键词 物联网 电力变压器 过热故障 红外检测 检测系统
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新型环保气体双三氟甲基硫醚的热稳定性研究
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作者 唐念 庞衍泽 +3 位作者 孙东伟 王中奥 张博雅 李兴文 《广东电力》 北大核心 2024年第9期29-35,共7页
为了降低SF_(6)高温室效应对环境的影响,寻找环境友好、性能优异的SF_(6)替代气体很有必要,双三氟甲基硫醚(CF_(3)SCF_(3))因其综合性能良好有望成为新一代SF_(6)替代气体。为了探究CF_(3)SCF_(3)的热稳定性,将CF_(3)SCF_(3)样品充入石... 为了降低SF_(6)高温室效应对环境的影响,寻找环境友好、性能优异的SF_(6)替代气体很有必要,双三氟甲基硫醚(CF_(3)SCF_(3))因其综合性能良好有望成为新一代SF_(6)替代气体。为了探究CF_(3)SCF_(3)的热稳定性,将CF_(3)SCF_(3)样品充入石英管中,使用管式炉加热该气体。在特定温度保持一定时间后,采集气体样品并送入气相色谱质谱联用仪中,提取样品色谱与色谱峰对应的质谱,并在NIST 2017数据库中搜索所获质谱以确定气体成分。研究发现:该气体在450℃时开始生成极少量CF 3 SSCF 3;在500℃时开始出现较为明显的分解;温度继续升高至550℃后,有更多气体分解,并出现了CF 3 CF 3、CS 2、CF 3 SCF 2 CF 3等更多分解产物。由此可知CF_(3)SCF_(3)热稳定性与C_(4)F_(7)N基本相当。研究成果为SF_(6)的环保替代提供了新选择。 展开更多
关键词 SF_(6)替代气体 高通量虚拟筛选 CF_(3)SCF_(3)分子 热稳定性 局部过热
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超大容量变压器外部结构件局部过热现象分析
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作者 谢辉 李程 《变压器》 2024年第8期69-72,共4页
油浸式超大容量变压器外部件局部过热发生典型部位,主要集中在大电流引线附近,是由大电流产生的磁通所造成的。本文作者通过应用三维模型仿真技术,控制结构件中杂散损耗,防止局部过热,并通过试验进行验证,对于过热部位给出相应的解决方案。
关键词 超大容量变压器 局部过热 漏磁分析
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催化裂化装置再生器二级旋分料腿结垢原因分析
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作者 程前进 《炼油技术与工程》 CAS 2024年第8期42-45,共4页
为查明某催化裂化装置再生器二级旋分料腿结垢原因,对垢样进行元素分析,结果表明金属元素在样品催化剂细粉中进行了富集。通过X射线衍射分析,证明催化剂细粉发生了熔融和黏结。再生器二级旋分料腿结垢的主要原因:金属元素的富集降低了... 为查明某催化裂化装置再生器二级旋分料腿结垢原因,对垢样进行元素分析,结果表明金属元素在样品催化剂细粉中进行了富集。通过X射线衍射分析,证明催化剂细粉发生了熔融和黏结。再生器二级旋分料腿结垢的主要原因:金属元素的富集降低了催化剂分子筛晶相结构崩塌温度。当CO及少量携带焦炭颗粒的细粉在二级旋分持续燃烧时,由于二级旋分内烟气夹带固体粒子很少,热阱作用减弱,使烟气温度骤升,当温度达到甚至超过催化剂细粉熔融温度时,细粉晶体结构破坏变为液相,在高速离心作用下黏附在料腿顶部形成垢层。通过再生器超温次数与垢样“年轮”层数关系比对,证明二旋料腿结垢与富氧再生环境及烧焦不均出现尾燃有对应关系,而金属元素富集降低了催化剂细粉的熔融温度。针对结垢原因,提出了相应的改进措施和建议。 展开更多
关键词 催化裂化装置 再生器 二级旋分料腿 结垢 金属元素 生焦率 超温 富氧再生
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220kV变压器箱沿连接铜排及螺栓过热的分析与处理
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作者 孙富强 张亚杰 +1 位作者 祝兆华 夏建国 《变压器》 2024年第9期22-25,共4页
本文作者针对几台220kV钟罩式油箱主变压器油箱上下节箱沿连接铜排及螺栓在运行过程中因电流过大而发热的问题进行了分析。通过研究螺栓过热的原因,提出了相应的解决措施,达到了降低连接铜排及螺栓温度的目的,确保了变压器的安全、稳定... 本文作者针对几台220kV钟罩式油箱主变压器油箱上下节箱沿连接铜排及螺栓在运行过程中因电流过大而发热的问题进行了分析。通过研究螺栓过热的原因,提出了相应的解决措施,达到了降低连接铜排及螺栓温度的目的,确保了变压器的安全、稳定运行。 展开更多
关键词 变压器 箱沿 铜排 过热
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