Kansai University
UniversitySuita, Japan
Research output, citation impact, and the most-cited recent papers from Kansai University (Japan). Aggregated across the NobleBlocks index of 300M+ scholarly works.
Top-cited papers from Kansai University
Willingness to communicate (WTC) is emerging as a concept to account for individuals’ first language (L1) and second language (L2) communication. This study examined relations among L2 learning and L2 communication variables in the Japanese English as a foreign language context using the WTC model and the socioeducational model as a framework. A L2 communication model was constructed and tested using AMOS version 4.0, with a sample of 297 Japanese university students. In the model, a latent variable, international posture, was hypothesized to capture the general attitude toward the international community and foreign language learning in Japan. From structural equation modeling, it appeared that international posture influences motivation, which, in turn, influences proficiency in English. Motivation affected self‐confidence in L2 communication which led to willingness to communicate in a L2. In addition to this indirect path, a direct path from international posture to WTC in a L2 was significant. The model’s fitness to the data was good, which indicates the potential for using the WTC and other constructs to account for L2 communication.
The properties of the bactericidal action of silver zeolite as affected by inorganic salts and ion chelators were similar to those of silver nitrate. The results suggest that the contact of the bacterial cell with silver zeolite, the consequent transfer of silver ion to the cell, and the generation of reactive oxygen species in the cell are involved in the bactericidal activity of silver zeolite.
The culture movement challenged the universality of the self-enhancement motive by proposing that the motive is pervasive in individualistic cultures (the West) but absent in collectivistic cultures (the East). The present research posited that Westerners and Easterners use different tactics to achieve the same goal: positive self-regard. Study 1 tested participants from differing cultural backgrounds (the United States vs. Japan), and Study 2 tested participants of differing self-construals (independent vs. interdependent). Americans and independents self-enhanced on individualistic attributes, whereas Japanese and interdependents self-enhanced on collectivistic attributes. Independents regarded individualistic attributes, whereas interdependents regarded collectivistic attributes, as personally important. Attribute importance mediated self-enhancement. Regardless of cultural background or self-construal, people self-enhance on personally important dimensions. Self-enhancement is a universal human motive.
This paper shows how the performance of evolutionary multiobjective optimization (EMO) algorithms can be improved by hybridization with local search. The main positive effect of the hybridization is the improvement in the convergence speed to the Pareto front. On the other hand, the main negative effect is the increase in the computation time per generation. Thus, the number of generations is decreased when the available computation time is limited. As a result, the global search ability of EMO algorithms is not fully utilized. These positive and negative effects are examined by computational experiments on multiobjective permutation flowshop scheduling problems. Results of our computational experiments clearly show the importance of striking a balance between genetic search and local search. In this paper, we first modify our former multiobjective genetic local search (MOGLS) algorithm by choosing only good individuals as initial solutions for local search and assigning an appropriate local search direction to each initial solution. Next, we demonstrate the importance of striking a balance between genetic search and local search through computational experiments. Then we compare the modified MOGLS with recently developed EMO algorithms: the strength Pareto evolutionary algorithm and revised nondominated sorting genetic algorithm. Finally, we demonstrate that a local search can be easily combined with those EMO algorithms for designing multiobjective memetic algorithms.
[1] At 14:46 local time on March 11, 2011, a magnitude 9.0 earthquake occurred off the coast of northeast Japan. This earthquake generated a tsunami that struck Japan as well as various locations around the Pacific Ocean. With the participation of researchers from throughout Japan, joint research groups conducted a tsunami survey along a 2000 km stretch of the Japanese coast. More than 5300 locations have been surveyed to date, generating the largest tsunami survey dataset in the world. On the Sendai Plain, the maximum inundation height was 19.5 m, and the tsunami bore propagated more than 5 km inland. Along the ria coast from about 50 to 200 km north of Sendai, the narrow bays focused the tsunami waves, generating the largest inundation heights and run-ups. The survey data clearly show a regional dependence of tsunami characteristics.
This article investigates results and antecedents of willingness to communicate (WTC) in a second Language (L2) through 2 separate investigations conducted with Japanese adolescent learners of English. In the first investigation, involving 160 students, a model was created based on the hypothesis that WTC results in more frequent communication in the L2 and that the attitudinal construct international posture leads to WTC and communication behavior. This model was tested with structural equation modeling and was found to fit the data well. The second investigation with 60 students who participated in a study‐abroad program in the United States confirmed the results of the first. Finally, frequency of communication was shown to correlate with satisfaction in interpersonal relationships during the sojourn.
An innovation of the aerobic oxidation of hydrocarbons through catalytic carbon radical generation under mild conditions was achieved by using N-hydroxyphthalimide (NHPI) as a key compound. Alkanes were successfully oxidized with O2 or air to valuable oxygen-containing compounds such as alcohols, ketones, and dicarboxylic acids by the combined catalytic system of NHPI and a transition metal such as Co or Mn. The NHPI-catalyzed oxidation of alkylbenzenes with dioxygen could be performed even under normal temperature and pressure of dioxygen. Xylenes and methylpyridines were also converted into phthalic acids and pyridinecarboxylic acids, respectively, in good yields. The present oxidation method was extended to the selective transformations of alcohols to carbonyl compounds and of alkynes to ynones. The epoxidation of alkenes using hydroperoxides or H2O2 generated in situ from hydrocarbons or alcohols and O 2 under the influence of the NHPI was demonstrated and seems to be a useful strategy for industrial applications. The NHPI method is applicable to a wide variety of organic syntheses via carbon radical intermediates. The catalytic carboxylation of alkanes was accomplished by the use of CO and O2 in the presence of NHPI. In addition, the reactions of alkanes with NO2 and SO2 catalyzed by NHPI provided efficient methods for the synthesis of nitroalkanes and sulfonic acids, respectively. A catalytic carbon-carbon bond forming reaction was achieved by allowing carbon radicals generated in situ from alkanes or alcohols to react with alkenes under mild conditions. 1 Introduction 2 Discovery of NHPI as Carbon Radical Producing Catalyst from Alkanes 2.1 Historical Background 2.2 Catalysis of NHPI in Aerobic Oxidation 3 NHPI-Catalyzed Aerobic Oxidation 3.1 Oxidation of Benzylic Compounds 3.2 Alkane Oxidations with Molecular Oxygen 3.3 Oxidation of Alkylbenzenes 3.4 Practical Oxidation of Methylpyridines 3.5 Preparation of Acetylenic Ketones via Alkyne Oxidation 3.6 Oxidation of Alcohols 3.7 Selective Oxidation of Sulfides to Sulfoxides 3.8 Production of Hydrogen Peroxide by Aerobic Oxidation of Alcohols 3.9 Epoxidation of Alkenes using Molecular Oxygen as Terminal Oxidant 4 Carboxylation of Alkanes with CO and O2 5 Utilization of NOx in Organic Synthesis 5.1 First Catalytic Nitration of Alkanes using NO2 5.2 Reaction of NO with Organic Compounds 6 Sulfoxidation of Alkanes Catalyzed by Vanadium 7 Carbon-Carbon Bond Forming Reaction via Catalytic Carbon Radicals Generated from Various Organic Compounds Assisted by NHPI 7.1 Oxyalkylation of Alkenes with Alkanes and Dioxygen 7.2 Synthesis of α-Hydroxy-γ-lactones by Addition of α-Hydroxy Carbon Radicals to Unsaturated Esters 7.3 Hydroxyacylation of Alkenes using 1,3-Dioxolanes and Dioxygen 8 Conclusions
Design of green, safe, and sustainable process for the synthesis of hydrogen peroxide (H2 O2 ) is a very important subject. Early reported processes, however, require hydrogen (H2 ) and palladium-based catalysts. Herein we propose a photocatalytic process for H2 O2 synthesis driven by metal-free catalysts with earth-abundant water and molecular oxygen (O2 ) as resources under sunlight irradiation (λ>400 nm). We use graphitic carbon nitride (g-C3 N4 ) containing electron-deficient aromatic diimide units as catalysts. Incorporating the diimide units positively shifts the valence-band potential of the catalysts, while maintaining sufficient conduction-band potential for O2 reduction. Visible light irradiation of the catalysts in pure water with O2 successfully produces H2 O2 by oxidation of water by the photoformed valence-band holes and selective two-electron reduction of O2 by the conduction band electrons.
Visible-light irradiation (λ > 450 nm) of gold nanoparticles loaded on a mixture of anatase/rutile TiO(2) particles (Degussa, P25) promotes efficient aerobic oxidation at room temperature. The photocatalytic activity critically depends on the catalyst architecture: Au particles with <5 nm diameter located at the interface of anatase/rutile TiO(2) particles behave as the active sites for reaction. This photocatalysis is promoted via plasmon activation of the Au particles by visible light followed by consecutive electron transfer in the Au/rutile/anatase contact site. The activated Au particles transfer their conduction electrons to rutile and then to adjacent anatase TiO(2). This catalyzes the oxidation of substrates by the positively charged Au particles along with reduction of O(2) by the conduction band electrons on the surface of anatase TiO(2). This plasmonic photocatalysis is successfully promoted by sunlight exposure and enables efficient and selective aerobic oxidation of alcohols at ambient temperature.
A novel method is proposed for simulating free-space propagation. This method is an improvement of the angular spectrum method (AS). The AS does not include any approximation of the propagation distance, because the formula thereof is derived directly from the Rayleigh-Sommerfeld equation. However, the AS is not an all-round method, because it produces severe numerical errors due to a sampling problem of the transfer function even in Fresnel regions. The proposed method resolves this problem by limiting the bandwidth of the propagation field and also expands the region in which exact fields can be calculated by the AS. A discussion on the validity of limiting the bandwidth is also presented.
We report here the synthesis of a zeolitic imidazolate framework-8 (ZIF-8) in an aqueous solution. ZIF-8 crystals were prepared by mixing 2-methylimidazole (Hmim) with Zn nitrate hexahydrate (Zn) in deionized water. The products prepared at high Hmim/Zn molar ratios were assigned to a sodalite (SOD)-type structure whose morphology consisted of a rhombic dodecahedron with truncated corners. The crystals possessed ultrahigh surface areas and micropore volumes. At low Hmim/Zn molar ratio, some zinc hydroxide and basic zinc nitrate were observed in the products. We also focused on the formation process of ZIF-8 crystals in an aqueous system by observing the change in the pH value as a function of synthesis time. We tried to calculate the stability constant of ZIF-8 by fitting the calculated pH values to the measured pH values. When the molar fractions of the zinc compounds in the equilibrium state were calculated, high fractions of the Zn(mim)2 complex were observed at high concentrations of Hmim. On the other hand, some zinc cations were present at low concentrations of Hmim. This finding would support a causal relationship between these zinc cations and the formation of some by-products.
Solar-to-chemical energy conversion is a challenging subject for renewable energy storage. In the past 40 years, overall water splitting into H2 and O2 by semiconductor photocatalysis has been studied extensively; however, they need noble metals and extreme care to avoid explosion of the mixed gases. Here we report that generating hydrogen peroxide (H2O2) from water and O2 by organic semiconductor photocatalysts could provide a new basis for clean energy storage without metal and explosion risk. We found that carbon nitride-aromatic diimide-graphene nanohybrids prepared by simple hydrothermal-calcination procedure produce H2O2 from pure water and O2 under visible light (λ > 420 nm). Photoexcitation of the semiconducting carbon nitride-aromatic diimide moiety transfers their conduction band electrons to graphene and enhances charge separation. The valence band holes on the semiconducting moiety oxidize water, while the electrons on the graphene moiety promote selective two-electron reduction of O2. This metal-free system produces H2O2 with solar-to-chemical energy conversion efficiency 0.20%, comparable to the highest levels achieved by powdered water-splitting photocatalysts.
The widespread adoption of ChatGPT, an AI language model, has the potential to bring about significant changes to the research, teaching, and learning of foreign languages. The present study aims to leverage this technology to perform automated essay scoring (AES) and evaluate its reliability and accuracy. Specifically, we utilized the GPT-3 text-davinci-003 model to automatically score all 12,100 essays contained in the ETS Corpus of Non-Native Written English (TOEFL11) and compared these scores to benchmark levels. The study also explored the extent to which linguistic features influence AES with GPT. The results showed that AES using GPT has a certain level of accuracy and reliability and could provide valuable support for human evaluations. Furthermore, the analysis revealed that utilizing linguistic features could enhance the accuracy of the scoring. These findings suggest that AI language models, such as ChatGPT, can be effectively utilized as AES tools, potentially revolutionizing methods of writing evaluation and feedback in both research and practice. The paper concludes by discussing the practical implications of using GPT for AES and exploring prospective future considerations.
Terahertz radiation was generated with several designs of photoconductive antennas (three dipoles, a bow tie, and a coplanar strip line) fabricated on low-temperature-grown (LT) GaAs and semi-insulating (SI) GaAs, and the emission properties of the photoconductive antennas were compared with each other. The radiation spectrum of each antenna was characterized with the photoconductive sampling technique. The total radiation power was also measured by a bolometer for comparison of the relative radiation power. The radiation spectra of the LT-GaAs-based and SI-GaAs-based photoconductive antennas of the same design showed no significant difference. The pump-power dependencies of the radiation power showed saturation for higher pump intensities, which was more serious in SI-GaAs-based antennas than in LT-GaAs-based antennas. We attributed the origin of the saturation to the field screening of the photocarriers.
TiO2 loaded with Au–Ag bimetallic alloy particles efficiently produces H2O2 from an O2-saturated ethanol/water mixture under UV irradiation. This is achieved via the double effects created by the alloy particles. One is the efficient photocatalytic reduction of O2 on the Au atoms promoting enhanced H2O2 formation, due to the efficient separation of photoformed electron–hole pairs at the alloy/TiO2 heterojunction. Second is the suppressed photocatalytic decomposition of formed H2O2 due to the decreased adsorption of H2O2 onto the Au atoms.
This book presents fundamental concepts and general approaches to City Logistics. City Logistics is the process of totally optimising urban logistics activities by considering the social, environmental, economic, financial and energy impacts of urban freight movement. City Logistics initiatives are required to solve urban freight transport problems including high levels of traffic congestion, negative environmental impacts, high energy consumption and a shortage of labour. The focus of this work is on modelling City Logistics.
At 14:46 local time on March 11, 2011, a magnitude 9.0 earthquake occurred off the coast of northeast Japan. This earthquake generated a tsunami that struck Japan as well as various locations around the Pacific Ocean. With the participation of about 300 researchers from throughout Japan, joint research groups conducted a tsunami survey along a 2,000 km stretch of the Japanese coast. More than 5,200 locations have been surveyed to date, generating the largest tsunami survey dataset in the world. The inundation height and run-up height were surveyed by laser, GPS, and other instruments, and the tidal correction has been accurately adjusted using a tidal database and a numerical simulation for Tohoku, an area where tide gauges were destroyed by the tsunami. Based on the survey dataset, the regional and local scale analyses were conducted to understand the basic characteristics of this event. Maximum run-up heights greater than 10 m are distributed along 500 km of coast in direct distance. The affected area of this event was several times larger than historically recorded in Tohoku. The mean inundation height in the southern Sanriku region is 10–15 m and there are several peaks of inundation along the coast from the northern to middle part of Sanriku.
This paper summarizes recent advances in α-alkylation reactions based on hydrogen borrowing methodologies using alcohol as an alkylating agent. This review provides a summary of recent progress toward the α-alkylation of carbonyl substrates, as well as relatively unactivated substrates bearing fewer acidic α-hydrogens, such as acetonitriles, acetamides, esters, methylpyrimidines, and methylquinolines. A summary of recent improvements in α-methylation strategies based on hydrogen borrowing methodologies has also been provided. Particular emphasis has been placed on highly practical and green chemistry approaches involving modified catalytic systems, including metal-supported heterogeneous catalysts and nanoparticle-based catalysts, as well as reactions conducted in the absence of a transition-metal catalyst. A review of recent achievements in methylation strategies using methanol as a methyl source, and their application to the α-methylation of ketones using transition-metal catalyzed hydrogen borrowing methodology, has also been documented.
Abstract This report demonstrates the first pH‐dependent synthesis of pepsin‐mediated gold nanoclusters (AuNCs) with blue‐, green‐, and red‐fluorescent emission from Au 5 (Au 8 ), Au 13 , and Au 25 , respectively. Pepsin is a gastric aspartic proteinase (molecular weight, 34 550 g/mol) that plays an integral role in the digestive process of vertebrates. It was found that the pH of the reaction solution was critical in determining the size of Au NCs (i.e., the number of gold atoms of AuNCs). Interestingly, enzyme function of pepsin contributes to the formation of these AuNCs. The photo‐stability of the Au 25 (or Au 13 ) NCs is much higher than that of Au 5 NCs (i.e., Au 25 ∼ Au 13 > > Au 5 ). The pepsin‐mediated Au 25 NCs were also found to be useful as fluorescent sensors for the detection of Pb 2+ ions by enhanced fluorescence and the detection of Hg 2+ ions by fluorescence quenching. Although the detailed formation mechanisms of these AuNCs require further analysis, the synthetic route using proteinase demonstrated here is promising for preparing new types of fluorescent metal nanoclusters for application in catalysis, optics, biological labeling, and sensing.
The decomposition of persistent and bioaccumulative perfluorooctanoic acid (PFOA) in water by UV-visible light irradiation, by H202 with UV-visible light irradiation, and by a tungstic heteropolyacid photocatalyst was examined to develop a technique to counteract stationary sources of PFOA. Direct photolysis proceeded slowly to produce CO2, F-, and short-chain perfluorocarboxylic acids. Compared to the direct photolysis, H2O2 was less effective in PFOA decomposition. On the other hand, the heteropolyacid photocatalyst led to efficient PFOA decomposition and the production of F- ions and CO2. The photocatalyst also suppressed the accumulation of short-chain perfluorocarboxylic acids in the reaction solution. PFOA in the concentrations of 0.34-3.35 mM, typical of those in wastewaters after an emulsifying process in fluoropolymer manufacture, was completely decomposed by the catalyst within 24 h of irradiation from a 200-W xenon-mercury lamp, with no accompanying catalyst degradation, permitting the catalyst to be reused in consecutive runs. Gas chromatography/mass spectrometry (GC/MS) measurements showed no trace of environmentally undesirable species such as CF4, which has a very high global-warming potential. When the (initial PFOA)/(initial catalyst) molar ratio was 10: 1, the turnover number for PFOA decomposition reached 4.33 over 24 h of irradiation.