三相三线有功电度表接线分析

在日常生活用电和工业用电遇到电度表多带负荷虽然很大,铝盘转速却很低,完全达不到所带负荷要求。有时铝盘不转甚至反转问题,现以三相三线有功电度表经电流互感器接入时的接线作一分析。     

Microstructural evolution of hybrid aluminum matrix composites reinforced with SiC nanoparticles and graphene/graphite prepared by powder metallurgy

The dispersion of ceramic nanoparticles is of significance to the microstructure and properties of particulate reinforced metal matrix composites.In this study,two hybrid enhancers,SiC-graphite and SiC-graphene nanosheets(GNSs),were incorporated into aluminum matrix composites using powder metallurgy.The dispersion of the reinforcements and microstructural evolution of the composites were characterized by using Scanning Electron Microscopy,X-Ray Diffraction,Transmission Electron Microscopy,and Raman spectroscopy.The results show that thin GNSs accelerated the deformation of the aluminum particles,and defects were introduced into the carbonaceous phases during the ball milling process.Al_4 C_3 needles generated during hot pressing,and were observed to bridge the aluminum grains.Compared with graphite,GNSs were more uniformly dispersed throughout the composite,which in turn restrained grain growth.As a result,a nanostructured composite(57.7 nm) was successfully produced upon the addition of SiC-GNSs.     

Zn1-xAlxO粉末样品的制备及结构表征

采用固相反应法制备了Zn1-xAlxO粉末样品。通过X射线衍射(XRD)和红外光谱(IR)对粉体的结构和光学性能进行了表征。结果表明:随着Al掺杂浓度逐渐加大,样品ZnO(101)衍射峰的峰位向高衍射角方向移动,x=0.024样品的晶粒大小随温度的升高而增大;通过FT-IR发现Al掺杂样品在427.78 cm-1和487.39 cm-1附近出现了Zn-O的吸收带,表现出良好的红外吸收特性。     

Numerical modeling of annular electromagnetic stirring with intercooling in direct chill casting of 7005 aluminum alloy billet

Uniform direct chill(UDC) casting method was developed by combining annular electromagnetic stirring(AEMS) with intercooling in direct chill casting. In order to investigate effect of UDC on flow patterns, temperature profiles and solidification during the casting, a numerical model of the UDC casting process was developed and used to simulate the UDC casting process for preparing 7005 aluminum alloy billets. The comparison of the calculated results of UDC casting with normal direct chill(NDC) casting indicated that flow patterns, temperature profiles and the sump depth are modified remarkably by the application of annular electromagnetic stirring and intercooling during the direct chill casting. The sump profile and the temperature history during UDC casing were studied, and the mechanism of the casting process were discussed. The comparisons between the simulations and experimental results suggested that the proposed model provides good agreement for the sump profiles and the temperature history within the billets.     

炼铝用碳阳极中三氟化铝作用机理的量子化学研究

本文采用ＣＮＤＯ／２方法研究了炼铝用碳阳极中添加三氟化铝的吸附行为，通过优化得到了吸附的最佳模型，量子化学计算结果表明；三氟化铝添加到炼铝用碳阳极中起传输电子的电桥作用，是碳阳极发生空气氧化以及铝电解时生成氧气的氧化反应的抑制剂，理论计算与实验结果吻合较好。     

渗流法制备泡沫铝金属材料的工艺参数研究

泡沫铝是一种新型的多孔功能材料。采用液相法中的渗流铸造法制备泡沫铝合金。结果表明,在泡沫铝孔结构的成形中,影响渗流深度和孔均匀性的主要工艺参数为填料粒子尺寸及其与模具的预热温度、铝液的浇注温度和真空度。     

铬天青S析相光度法测定痕量铝

研究了显色剂铬天青S与铝生成配合物的反应条件及其在OP中的析相条件。室温,铝与CAS络合形成1:2的配合物,最大吸收波长为620nm,ε620=1.09×105L?mol-1?cm-1,铝含量在0-10μg/50ml范围内符合朗伯-比尔定律;析相温度95℃,析相时间1h。     

中频反应磁控溅射制备氧化铝薄膜的工艺探索

采用中频反应磁控溅射工艺进行氧化铝薄膜的沉积实验,研究了反应气体(O2)含量和溅射功率与薄膜沉积速率的关系,并探讨了氧化铝薄膜制备过程中存在的"迟滞回线"问题.     

The inhibition of corrosion of aluminum in acid environment byin situ electrocoagulation of polybutadienoic acid

The dissolution rate of naked Al sheet in the acidic solutions containing polybutadienoic acid (PBA) with pH value of 0.3∼3.0 at 20∼60°C has been determined by electrometry and gravimetry methods. The form of electroactive Al(III) ions occurred on the anode and the behavior of electrocoagulation of PBA have been approached. The results indicate that the superior condition of electrocoagulation of water-soluble nonsaturable low polymer PBA is the adoption of the electroactive Al(III) ions occurred in electrolyte containing 1.0 g·L⁻¹ PBA+0.2 mol·L⁻¹C₆H₈O₇ citric acid with pH value of 3.0 at 30°C. The mechanism of corrosion-inhibited or electrocoagulation resulted from the electroactive Al(III) ions coordinate-COOH group of PBA and free ions of citric groups into the aluminum soaps with bicyclic structure are briefly discussed in this paper. Supported by the National Natural Science Foundation of China Tao Yingchu: born in 1943, Professor     

磺化铝酞菁在微量蛋白分析中的应用

利用蛋白质对磺化铝酞菁的吸附特性，建立了一种测量微量蛋白的方法．观测了多种影响因素，并探讨了其机理，与传统方法相比，本法具有简便快速的特点，测定结果较满意．牛血清白蛋白测定的线性范围为０．６７～８．００ｍｇ／Ｌ，检出限为０．５５ｍｇ／Ｌ，精密度为６．７％