Performance prediction of a hybrid‐excitation synchronous machine with axially arranged excitation poles and permanent‐magnet poles

This paper presents a method of predicting the steady‐state performance of a new hybrid‐excitation synchronous machine (HESM) theoretically. The field pole of this HESM is axially divided into two parts; one is an excitation part and the other a permanent‐magnet (PM) part. A nonlinear equivalent circuit, which can include the saliency of the rotor and the magnetic saturation due to the iron core, is derived. Based on this equivalent circuit, the steady‐state performance of the HESM is calculated, and the results are confirmed through experiments. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 43–49, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20033     

Preparation of samples for proficiency testing of pesticide residue analysis in processed foods

To conduct proficiency testing for the analysis of pesticide residues in processed foods, fortified samples of retort curry and pancake were examined. In the case of retort curry, heating and mixing were necessary at the time of preparation to provide a homogenous analytical sample. A mixture of 4 carbamates and 11 organophosphorus pesticides was spiked and 14 of them showed consistent results in the samples. In the case of pancake, 10 kinds of pesticides were added to the pastry. The prepared pastry was them cooked. The relative concentrations of most of the pesticides in the pancake were not affected and all the pesticides showed consistent results in the samples. These results showed that the two tested samples were suitable for proficiency testing.     

Distribution, characteristics, and worldwide inventory of dioxins in kaolin ball clays

Distribution, characteristics, and global inventory of dioxins (polychlorinated dibenzo-p-dioxins [PCDDs] and dibenzofurans [PCDFs] and dioxin like polychlorinated biphenyls) in kaolin clays collected from 10 countries were investigated. Dioxins were found in all kaolin clay samples analyzed, at total concentrations ranging from 1.2 pg/g (Brazil) to 520,000 pg/g (USA). Dioxin concentrations in kaolin clays from a few countries (e.g., Brazil and UK) were lower than those reported for background soils in Japan. Dioxin profiles in kaolin clays were characterized by the domination of the congener octachlorodibenzo-p-dioxin (OCDD), and the concentrations of other congeners decreased in the order of reduction in the levels of chlorination. Furthermore, specific distribution of congeners, with predominant proportions of 1,4,6,9-substituted PCDDs within each homologue group, was found in most clay samples. The ratios of concentrations of PCDD to PCDF and 1,2,3,7,8,9-HxCDD to 1,2,3,6,7,8-HxCDD indicated differences in the profiles found for anthropogenic sources (including pentachlorophenol) and kaolin clays. Concentrations of PCDD/Fs in kaolin clays, except for American ball clays, did not exceed the environmental criteria set by the Law Concerning Special Measures against Dioxins in Japan. Based on the average concentrations measured in our study, inventories of PCDD/Fs from the production/usage of ball clays on a global scale were estimated to be 650 kg/yr; the corresponding value on a TEQ basis is 2400 g-TEQ/yr. More than 480 kg of OCDD is estimated to be released annually from the production of kaolin clays worldwide, suggesting that kaolin clays can be a major contributor for additional source of dioxins, especially OCDD, in the environment.     

Correlations of Hepatic Hemodynamics,Liver Function,and Fibrosis Markers in Nonalcoholic Fatty Liver Disease: Comparison with Chronic Hepatitis Related to Hepatitis C Virus

The progression of chronic liver disease differs by etiology. The aim of this study was to elucidate the difference in disease progression between chronic hepatitis C (CHC) and nonalcoholic fatty liver disease (NAFLD) by means of fibrosis markers, liver function, and hepatic tissue blood flow (TBF). Xenon computed tomography (Xe-CT) was performed in 139 patients with NAFLD and 152 patients with CHC (including liver cirrhosis (LC)). The cutoff values for fibrosis markers were compared between NAFLD and CHC, and correlations between hepatic TBF and liver function tests were examined at each fibrosis stage. The cutoff values for detection of the advanced fibrosis stage were lower in NAFLD than in CHC. Although portal venous TBF (PVTBF) correlated with liver function tests, PVTBF in initial LC caused by nonalcoholic steatohepatitis (NASH-LC) was significantly lower than that in hepatitis C virus (C-LC) (p = 0.014). Conversely, the liver function tests in NASH-LC were higher than those in C-LC (p < 0.05). It is important to recognize the difference between NAFLD and CHC. We concluded that changes in hepatic blood flow occurred during the earliest stage of hepatic fibrosis in patients with NAFLD; therefore, patients with NAFLD need to be followed carefully.     

Electron transfer reactions of some ferrous complexes of substituted 1,10-phenanthroline

The cyclic voltammograms of ferrous complexes of 5-substituted 1,10-phenanthroline were obtained. The anodic and the cathodic peak potentials shifted toward positive side by substituting electron-withdrawing group for 5-hydrogen in 1,10-phenanthroline. This result was interpreted by that the probability of the transition of electron from d orbital to the empty MO of the ligand was increased by the introduction of electron-withdrawing group, and hence the oxidation of the ferrous complex became more difficult. The oxidized substances of ferrous complex containing this functional group were labile and decomposed chemically.     

Risk of cancer and non-cancer diseases in the atomic bomb survivors

Late health effects of exposure to atomic bomb radiation have been evaluated in survivors. A cohort of 120 321 people has been followed since 1950 for mortality, including the cause of death using the Japanese population registry system (Life Span Study), and for cancer incidence using population-based cancer registries. Findings have included a markedly increased risk of leukaemia several years after the exposure, increased risk of various malignant tumours several decades after the exposure and, more recently, findings of increased rates of non-cancer diseases such as cardiovascular diseases.     

Electrochemical and spectroscopic studies of molybdenum(VI) complexes with aminopolycarboxylic acids

The complexes of molybdenum(VI) with iminodiacetic acid (IDA), nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid (EDTA) were investigated by means of polarographic and spectroscopic methods. The composition of the complexes was determined by the Job's method as following: 1Mo(VI)/1IDA; 1Mo(VI)/1NTA and 2Mo(VI)/1EDTA. The polarographic wave height was fairly dependent on the nature of the complexes. The overall reaction rate for the reduction of Mo(VI)-IDA complex was limited by diffusion. On the other hand, the polarographic reduction of Mo(VI)-NTA and - EDTA complexes were kinetically controlled by the preceding chemical reaction which was composed of protonation, dimerization and substitution of ligands, however, the rate-determining step was the substitution of ligands. The mechanism for the electroreduction of each complex was discussed.