Electrical Conduction in β-Bi2O3 Doped with Sb2O3

Electrical conduction in tetragonal β-Bi₂O₃ doped with Sb₂O₃ was investigated by measuring electrical conductivity, ionic transference number, and Seebeck coefficient. The β-Bi₂O₃ doped with 1 to 10 mol% Sb₂O₃ was stable up to 600°C and showed an oxygen ionic and electronic mixed conduction, where the electron conduction was predominant at low oxygen pressures. The oxygen-ion conductivity showed a maximum at 4 mol% Sb₂O₃, whereas the activation energy for the ionic conduction remained unchanged for 4 to 10 mol% Sb₂O₃-doped specimens. These results were interpreted in terms of the oxygen vacancy concentration and the distortion of the tetragonal structure. The electron conductivity and its oxygen pressure dependence decreased with increasing Sb₂O₃ content. The fact that Sb⁵⁺ is partially reduced by excess electrons in heavily doped β specimens at low oxygen pressures is explained.     

Dependence of Vacuum Electrical Breakdown Field and Field Enhancement Factor on the Number of Apertures Drilled in Small Electrodes

Dark current based on field emission current is considered to be a factor causing the vacuum electrical breakdown between multiaperture acceleration grids in the JT‐60 negative ion source. In this paper, we focus on field enhancement factor, which is a key parameter of field emission from the electrode. Vacuum breakdown testing for small‐sized electrodes simulating the multiaperture acceleration grids of the negative ion source was performed. We found the field enhancement factor and breakdown field for multiaperture electrodes, and we investigated the dependence of each parameter on the number of apertures. The results revealed that an increase in the average field enhancement factor after the end of conditioning resulting from an increase in the number of apertures led to a decrease in the dielectric strength of the multiaperture electrodes.     

Iron Loss Analysis of Permanent Magnet Motors Fed by PWM Inverter

Carrier harmonic losses that consist of iron loss, eddy current loss, and ac copper loss are produced in a permanent magnet machine driven by a PWM inverter. It is already known that a higher motor inductance can lead to lower carrier harmonic losses. This paper investigates the carrier harmonic loss composition of two motors with identical dimensions but different inductances. The results of finite element analysis (FEA) showed that the eddy current loss in the iron core accounts for most of the carrier harmonic loss. It is also shown that the carrier harmonic loss of the iron core is quantifiable using theoretical calculations.     

Dynamic scheduling system utilizing machine learning as a knowledge acquisition tool

Dynamic selection of scheduling rules during real operations has been recognized as a promising approach to the scheduling of the production line. For this strategy to work effectively, sufficient knowledge is required to enable prediction of which rule is the best to use under the current line status. In this paper, a new learning algorithm for acquiring such knowledge is proposed. In this algorithm, a binary decision tree is automatically generated using empirical data obtained by iterative production line simulations, and it decides in real time which rule to be used at decision points during the actual production operations. The configuration of the developed dynamic scheduling system and the learning algorithm are described in detail. Simulation results on its application to the dispatching problem are discussed with regard to its scheduling performance and learning capability.     

System Voltage Control Based on Potential Game Theory Considering PV Output Prediction Error

Recently, in Japan, large‐scale introduction of photovoltaics (PVs) has been under way. This development increases the likelihood of system voltage increase and fluctuations, which can be prevented by employing PV output prediction. In this study, we focus our attention on applying PV output prediction to system operation with the objective of system voltage control. In this paper, 30‐min ahead prediction is assumed according to prior research with prediction error consideration. System voltages of 30 min ahead are estimated and are controlled in advance by using transformer taps and static capacitors. In this paper, voltage control is proposed for coordinating control, which is based on one of the games in the game theory, potential game. The validity of the proposed method is confirmed by running simulations using a modified IEEE 30 bus system. By applying the proposed method, both the voltage deviations and control counts improved considerably compared to a conventional method.     

Voltage Control Using PV Power Factor,Static Capacitor,and Transformer Tap for Large PV Penetration

The Japanese government has set 53 GW as the target level of PV deployment by 2030. However, the large‐scale introduction of PV will cause several problems in power systems. One of these problems is the increase in voltage due to decreased load demands associated with large PV active power output. Another problem is voltage variations caused by fluctuations in PV system output. In this paper, we focus our attention on the voltage and reactive power control for large‐scale PV deployment and propose voltage control using the PF (PV power factor), SC (static capacitor), and TAP (transformer tap). In the proposed method, the SC and TAP controls consider voltage stability through the use of VMPI‐i and VMPI‐i sensitivity, and the PF control suppresses voltage variation and voltage spikes. Finally, we simulate these controls using the Ward–Hale system to verify the validity of the proposed method.     

EXTRACTION ENHANCEMENT OF TITANIUM(IV) ACETYLACETONATE IN THE PRESENCE OF PHENOLS

ABSTRACT

The effects of phenols as additives on the solvent extraction of titanium(IV) with acetylacetone in carbon tetrachloride have been investigated. Titanium(IV) is scarcely extracted with acetylacetone, and the extractability is lower than that of the other titanium group metals, zirconium(IV) and hafnium(IV). However, the extractability of titanium(IV) acety lacetonate is greatly enhanced in the presence of 3,5-dichlorophenol where titanium(IV) can be extracted quantitatively and better than zirconium(IV) or hafnium(IV). The effects of the phenols (3,5-dichlorophenol, 3,5-dimethylphenol, and 4-chlorophenol) are greater than that of benzoic acid, and the phenol with the lower pK_a value is more effective. From equilibrium analy sis on the extraction system using 3,5-dichlorophenol (Hdcp), it was found that one mole of titanium(IV) is extracted together with two moles of acetylacetone (Hacac) and one to three moles of the phenol; one of the extracted species is suggested to be Ti(acac)₂(dcp)₂Hdcp.     

Investigation of Degradation and Voltage Response of Lithium‐Ion Battery Based on Impedance and Electromotive Force Measurement

Detailed information on degradation process of lithium‐ion batteries is essential to manage the batteries throughout their lifetime because degradation of the batteries associated with long‐term usage is inevitable. To evaluate degradation degree of the batteries in detail, it is necessary to separately make clear the decrease in output power due to the increase in AC impedance and the decrease in battery capacity caused by the decrease in electromotive force. In this study, therefore, the authors at first propose a new evaluation method of detailed degradation process of lithium‐ion batteries through measurements of AC impedance and electromotive force of degraded batteries. It is made clear that this proposed evaluation method can provide simple but detailed diagnosis of battery degradation degree, indicating usefulness of the proposed method. Next, as a first step for performance simulation of degraded lithium‐ion batteries, the authors make clear that the already developed simulation method of battery transient voltage response, validity of which has been confirmed only for new batteries, is also applicable to degraded batteries.     

Viscoelastic Properties of Whey Protein Gels: Mechanical Model and Effects of Protein Concentration on Creep

The creep behavior of gels made using different concentrations of whey protein isolate (WPI, >95% protein) was systematically determined. The creep curves of these gels conformed to a six element mechanical model consisting of one Hookean, two Voigt and one Newtonian component. The concentration and temperature dependence of each viscoelastic constant were examined and the data are discussed in terms of mechanisms involved in gel network structure.     

一株中度嗜盐菌SL21合成Ectoine的研究

从大连市普兰店盐场盐池淤泥中筛选出一株中度嗜盐细菌SL 21,对其进行形态和分子生物学鉴定.运用16 S rDNA技术建立SL 21系统发育树.该菌株为革兰氏阴性细菌,短杆状,最适生长NaCl浓度是10%.以其16S rDNA序列相似性为基础构建了包括7种相关种属在内的系统发育树.结果表明,SL 21与Halomonas venusta的同源性达到99%以上,应归属于盐单胞菌属.研究了中度嗜盐菌SL21的渗透压补偿溶质(Ectoine)的生成及生成条件.用含2 mol.L-1NaCl的肉汤培养基,在30℃条件下,培养48 h,诱导生成Ectoine为285.1 mg.L-1,其Ectoine生成的最适诱导温度是30℃,最适NaCl浓度是2 mol.L-1.