[in Japanese]

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Polyacrylamide(PAA) cryogels containing iron hydroxide oxide(FeOOH) nanoparticles were prepared and used for the fixed bed continuous adsorption of As(V) from water. The effect of inlet As(V) concentration and feed flow rate on the breakthrough characteristics of the fixed bed continuous adsorption were investigated. The cryogels have a large number of pores with µm order and FeOOH nanoparticles are observed on the surface and inside of the wall of the cryogels. Hence it was found that As element was observed and overlapped with Fe element by EDX mapping analysis, As(V) was adsorbed on FeOOH from aqueous phase. The breakthrough curves of the fixed bed adsorption were analyzed using the well-established column models which are Yoon-Nelson and Thomas models. The calculated results were well fitted with both models at high inlet concentrations and slow feed rate rather than that at low one and fast one. The maximum adsorption amount of As(V) on the FeOOH particles in the cryogels, which was obtained from the fixed bed adsorption at the inlet concentration of As(V), showed Langmuir type adsorption isotherm. The FeOOH particles prepared and the FeOOH particles entrapped in PAA cryogels were determined to be α-FeOOH by FT-IR spectrum. The XPS analysis of FeOOH-PAA cryogel after adsorption of As(V) detected As-3d peak and the shape change of O-1s peak.

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With the aim for the easy estimation, as a daily work, of volume of liquid nitrogen in metal tanks in which liquid nitrogen cannot be observed directly, in the present paper a simply structured and non-electric weight scale is proposed. The proposed weight scale consists only of a bedplate with vibration suppression rubber to lift liquid nitrogen tanks, an L-shape component connected to the bedplate, and a conventional ruler. The principle of the mass measurement is the following. The length of the rubber working as spring material changes depending on the amount of liquid nitrogen, i.e. the mass of a liquid nitrogen tank, following the classical Hooke’s law; hence, the height of the bedplate also changes. The L-shape component detects the vertical displacement of the bedplate, magnifies it by the ratio of the two arms of this L-shape component, and converts into a horizontal displacement. This magnified displacement is measured with the conventional ruler. With this weight scale the mass and volume of liquid nitrogen in tanks can be estimated with the accuracy of 1.0 kg and 1.2 L, respectively. This accuracy of the proposed scale is not small but within an acceptable range for the rough estimation of liquid nitrogen. Only the Hooke’s law and elemental geometry with some trigonometric functions are utilized to construct the proposed weight scale; thus, even in high school and university students can construct and repair this scale by themselves. Moreover, the proposed weight scale may also be suitable for an educational material for classical physics in the field of education in high school and university.

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[in Japanese]

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Out-of-class study hours of Japanese university students are significantly shorter than those of American university students. Assignments are practical method to encourage students to study. However, professors have many responsibilities and giving feedback to each student is difficult. Effectively utilizing learning management system (LMS) can encourage students to study in out-of-class hours and to lessen professors’ burden of scoring. However, the system is not fully introduced nor utilized in every university in Japan. In this paper, an LMS-like environment was built by using Google Apps in order to solve these problems in a university without LMS. The proposed environment was implemented in an English course for one semester. The result showed that the environment enabled efficient scoring of assignments and effective recording of the students’ learning activities: when given a reading assignment from past EIKEN P1 grade reading sections composed of three question sets totaling 10 questions with 2,041 words, average study hour of the students was 70 minutes. Time required to construct the environment was long but the time required for operation was short, suggesting professors could increase their research activities.

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The selenium distribution in the scale, the skin or the endothelium as inedible tissues and the ordinary muscle of several species of fish (Japanese horse mackerel Trachurus japonicus, Chub mackerel Scomber japonicus, Largehead hairtail Trichiurus lepturus and Doggertooth pike conger Muraenesox cinereus) which have generally been known as the special marine products from Oita Prefecture was investigated in order to clarify the possibility of the available utilization of selenium especially from inedible tissues, in relation with the mercury distribution involving the tissues. As results, both levels of selenium and mercury in the ordinary muscle of the subjected fish were higher than those from the other ocean areas. Each mercury and selenium level in those inedible tissues of all subjected species was about the same and high compared with that involving muscle, respectively. On the other hand, from the selenium molar fraction involving inedible tissues, the low oxidation states of selenium species was almost predominant in all subjected species, as not in the case of involving ordinary muscle. The Se/Hg (the molar ratio of selenium to mercury) as an indicator of the safety of marine products was also extremely high compared with that involving ordinary muscle, suggesting that the scale, the skin or the endothelium will be usually inedible but significantly safe tissue in which little levels of heavy metals such as mercury will tend to accumulate, as in the case of a preceding paper. These findings suggested that the available utilization of selenium will be expected from the scale, the skin or the endothelium as inedible tissues of fish regardless of inhabiting waters, including the improvement of the environment.

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It has investigated using a Clark-type oxygen electrode and an ESR method that the conformation of thiol-compounds such as cysteine (Cys) and glutathione (GSH) effects on the formation of a nitrosyl(protoporphyrinato)iron(II) complex by the reaction between hydroxo(protoporphyrinato)iron(III) complex adsorbed on magnesium oxide (Heme/MgO) powder and the nitrite ion (NO2–). The oxygen consumption rate of the Heme/MgO with Cys was slightly higher than that of the Heme/MgO with GSH. However, a nitrosyl(protoporphyrinato)iron(II) complex produced by the Heme/MgO with GSH was lower than that produced by the Heme/MgO with Cys under the concentration of NO2– below 0.1 mmol dm–3. This result suggests that the conformational effect of thiol-compounds plays a key role on the formation of the nitrosyl(protoporphyrinato)iron(II) complex during the reduction of NO2– to nitrogen monoxide (NO). A possible mechanism for the conformational effect of GSH on the formation of the nitrosyl(protoporphyrinato)iron(II) complex is discussed, as a characteristic feature of the molecular size of GSH and an electronic interaction (repulsion) between GSH and NO2–.

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It is well known that the lithium secondary battery (LiSB) is the most promising power source for electric vehicle (EV), the further development is still needed to assure the life and performance prediction of LiSB. Mathematical modelling of overvoltage relaxation for batteries has been carried out by applying piggyback stacked dual transmission line as an equivalent circuit of electrode for commercially available batteries. Derived functions were quite complicated. However, we succeeded to express the overvoltage relaxation after current interruption. For the overvoltage relaxation, we succeeded to obtain the accurate response within 1 mV residuals for 10 minutes relaxation by simply connecting two dual transmission line in series.

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Vegetables and fruits are known as an excellent source of anti-oxidant components. However, their anti-oxidant activities are predicted to depend on their producing areas and cooking methods. In the present study, we investigated anti-oxidative activities on Abutomato (tomato), Tamagenasu (eggplant) and Kurimasaru (pumpkin) cultivated in Yamaguchi Prefecture in Japan, after they cooked as well. We measured hydrophilic oxygen radical absorbance capacity (H-ORAC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and total polyphenol content of three vegetables with or without cooking, and evaluated their relevance. Anti-oxidative activities of these vegetables were not altered by cooking using electric oven and microwave. Furthermore, whether or not tomato seeds were removed did not affect the activities during cooking. These findings suggested that the three vegetables retain the original anti-oxidative capacities even though cooked using electric oven and microwave.

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Scores of English certificate exams have been drawing increasing attention as one of the indexes for English learning activities. The certificate exams can evaluate proficiency of test takers objectively. However, the exams are usually expensive to take, making it difficult for students to take ones frequently. If students’ proficiency based on certificate exams’ result can be estimated by using learning outcomes of English course, their objective proficiency can be assessed without additional cost. This study used learning outcomes of 76 students in a public university in Ishikawa. Their learning outcomes (weighted average scores of mid-term and final exams, assignment average scores, assignment average study hours, times of assignment submission) in an English reading course in 2018 fall semester and reading scores of TOEIC Bridge in February of 2019 were used for discriminant analysis. A model using weighted average sores of mid-term and final exams and assignments average scores yielded 89.04% accuracy to classify the students into upper and lower groups. The threshold of the two groups are set on 80 % correct score of TOEIC Bridge reading scores. The results also showed a necessity to give students appropriately calibrated assignments on regular basis.

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