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PREPARATION OF MICRON-SIZED NONSPHERICAL POLYSTYRENE/POLY(STYRENE-co-ETHYLENEGLYCOL DIMETHACRYLATE) PARTICLES BY SEEDED SOAP-FREE EMULSION POLYMERIZATION

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Chinese Journal of Polymer Science 2011年第5期29卷 634-638页

作者：石山 Shin-ichi kuroda Key Laboratory of Applied Technology of Polymer Materials College of Materials Science and EngineeringShenyang University of Chemical Technology Department of Production Science and Technology Faculty of EngineeringGunma UniversityOta 373-0057Japan

Micron-sized nonspherical polymer particles having different morphologies were synthesized by seeded soap-free emulsion polymerization of styrene （St） and ethyleneglycol dimethacrylate （EGDMA, used as a crosslinker） on spherical, linear polystyrene （PS） seed particles. The morphology of the resulting PS/poly（St-co-EGDMA） particles was dependent on the crosslinker concentration and polymerization temperature.

关键词： Nonspherical Polymer particles Seeded soap-free emulsion polymerization Crosslinking.

Kinetic study of all-or-none hemolysis induced by cationic amphiphilic polymethacrylates with antimicrobial activity

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Chinese Chemical Letters 2015年第4期26卷 479-484页

作者： Kazuma Yasuhara Kenichi kuroda Graduate School of Materials Science Nara Institute of Science and Technology Department of Biologic and Materials Sciences University of Michigan School of Dentistry

To gain an understanding of the toxicity of antimicrobial polymers to human cells, their hemolytic action was investigated using human red blood cells （RBCs）. We examined the hemolysis induced by cationic amphiphilic methacrylate random copolymers, which have amino ethyl sidechains as cationic units and either butyl or methyl methacpjlate as hydrophobic units. The polymer with 30 tool% butyl sidechains （B3o） displayed higher hemolytic toxicity than the polymer with 59 tool% methyl sidechains （Ms9）. B3o also induced faster release of hemoglobin from RBCs than lVlsg. A new theoretical model is proposed based on two consecutive steps to form active polymer species on the RBC membranes, which are associated to RBC lysis. This model takes the all-or-none release of hemoglobin by the rupture of RBCs into account, providing new insight into the polymer-induced hemolysis regarding how individual or collective ceils respond to the polymers.

关键词： HemolysisAntimicrobial polymerAmphiphilic polymethacrylateKinetic analysisMembrane disruption

Differences in dinucleotide frequencies of thermophilic genes encoding water soluble and membrane proteins

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第6期12卷 419-427页

作者： Hiroshi NAKASHIMA Yuka kuroda Department of Clinical Laboratory Science Graduate Course of Medical Science and TechnologySchool of Health SciencesKanazawa University

The occurrence frequencies of the dinucleotides of genes of three thermophilic and three mesophilic species from both archaea and eubacteria were investigated in this study. The genes encoding water soluble proteins were rich in the dinucleotides of purine dimers, whereas the genes encoding membrane proteins were rich in pyrimidine dimers. The dinucleotides of purine dimers are the counterparts of pyrimidine dimers in a double-stranded DNA. The purine/pyrimidine dimers were favored in the thermophiles but not in the mesophiles, based on comparisons of observed and expected frequencies. This finding is in agreement with our previous study which showed that purine/pyrimidine dimers are positive factors that increase the thermal stability of DNA. The dinucleotides AA, AG, and GA are components of the codons of charged residues of Glu, Asp, Lys, and Arg, and the dinucleotides TT, CT, and TC are components of the codons of hydrophobic residues of Leu, Ile, and Phe. This is consistent with the suitabilities of the different amino acid residues for water soluble and membrane proteins. Our analysis provides a picture of how thermophilic species produce water soluble and membrane proteins with distinctive characters: the genes encoding water soluble proteins use DNA sequences rich in purine dimers, and the genes encoding membrane proteins use DNA sequences rich in pyrimidine dimers on the opposite strand.

关键词： Water soluble and membrane proteins Purine/pyrimidine dimers Thermophilic and mesophilic species Dinucleotide frequencies

Progress in numerical simulation of cavitating water jets

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Journal of Hydrodynamics 2013年第4期25卷 502-509页

作者： PENG Guoyi SHIMIZU seiji College of Engineering Nihon University

This paper reviews recent progress made toward modeling of cavitation and numerical simulation of cavitating water jets. Properties of existing cavitation models are discussed and a compressible mixture flow method for the numerical simulation of high- speed water jets accompanied by intensive cavitation is introduced. Two-phase fluids media of cavitating flow are treated as a homo- geneous bubbly mixture and the mean flow is computed by solving Reynolds-Averaged Navier-Stokes （RANS） equations for com- pressible fluid. The intensity of cavitation is evaluated by the gas volume fraction, which is governed by the compressibility of bubble-liquid mixture corresponding to the status of mean flow field. Numerical results of cavitating water jet issuing from an orifice nozzle are presented and its applicability to intensively cavitating jets is demonstrated. However, the effect of impact pressure caused by collapsing of bubbles is neglected, and effectively coupling of the present compressible mixture flow method with the dynamics of bubbles remains to be a challenge.

关键词： cavitation water jet multi-phase flow numerical simulation

Hand-holding and releasing between the anion and cation to change their macroscopic behavior in water

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Green Energy & Environment 2019年第2期4卷 127-130页

作者： Kosuke kuroda Yumiko Shimada Kenji Takahashi Faculty of Biological Science and Technology Institute of Science and Engineering Kanazawa University

Despite the similarity of ionic liquid and zwitterion, their some properties such as conductivity and hydrophobicity are different. Here we developed a novel phosphonium salt having a dynamic covalent bond between anion and cation, enabling reversible structural shift between free ion pair and zwitterion. With the phosphonium salt, control of the macroscopic phase behavior in aqueous solution, i.e. forming mono-or biphasic systems, upon exposure to an acid or base was reversibly achieved, based on the structural shift of the phosphonium salt. CO_2/N_2 bubbling reversibly changed the phase behavior as well as acid/base, leading to green separation systems.

关键词： Ionic liquid Zwitterion Phase separation Dynamic covalent bond

Silicification in Mississippian Lodgepole Formation,Northeastern Flank of Williston Basin,Manitoba,Canada

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Journal of Earth Science 2012年第1期23卷 1-18页

作者： Harvey R Young Moe kuroda Department of Geology Brandon University

Five types of replacement silica are recognized in the Lower Mississippian Virden Member carbonates on the northeastern flank of Williston basin： microcrystalline quartz, chalcedonic quartz, anhedral megaquartz, euhedral megaquartz, and stringy megaquartz. Silica tends to replace various bioclasts, and all except the stringy megaquartz also occur as non-replacive void-filling cement or as silica forming chert nodules and silicified limestone. Although crinoids, brachiopods, corals, bryozoans, molluscs, trilobites, forams, and ostracodes are present in the sediments studied, only the first three show evidence of silicification. Crinoids are commonly replaced by microcrystalline quartz whereas brachiopods typically by spherules of length slow chalcedony. Coalesced spherules, often in concentric rings （beekite rings）, may form sheet-like masses on the surface of corals and brachiopods. Although bryozoans are common in the Virden Member, none showed any evidence of silicification. The difference in the susceptibility to silicification may be related to the shell microstructure, biological group, size of organism, skeletal mineralogy, and organic content of the bioclasts. Biogenic silica derived from the dissolution of siliceous sponge spicules is considered to be the most likely silica source for silicification. Most silica is believed to be released during early diagenesis before the sediments were deeply buried. The Virden Member carbonate may have experienced two episodes of replacement, the first affecting the bioclasts, the second producing silicified limestone and chert nodules.

关键词： silicification Williston basin Lodgepole Formation Virden Member Mississippian carbonate.

Analysis of Laser-Induced Plume During Disk Laser Welding at Different Speeds

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Plasma Science and Technology 2013年第8期15卷 821-824页

作者：王腾高向东 Katayama seiji School of Electromechanical Engineering Guangdong University of Technology School of Computer South China Normal University Joining and Welding Research Institute Osaka University

During high power disk laser welding, the high-speed photography was used to measure the dynamic images of the laser-induced plume at different laser welding speeds. Various plume features （area, height and brightness） were extracted from the images by the color space clustering algorithm. Combined with observation on the surface and the cross sections of welding samples, the effect of welding speed on welding stability was analyzed. From the experimental results, it was found that these features of plume could reflect the welding state. Thus changes of the plume features corresponded to different welding speeds, which was helpful for monitoring the laser welding stability.

关键词： disk laser welding laser-induced plume stability high-speed photography different welding speeds

Conservation Design for Traditional Agricultural Villages: A Case Study of Shirakawa-go and Gokayama in Japan

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Built Heritage 2019年第2期3卷 7-23页

作者： Nobu kuroda World Heritage Studies Faculty of Art and DesignUniversity of TsukubaIbarakiJapan

Agricultural villages in Japan are declining and disappearing *** an agricultural village goes extinct,its tradition and culture die as *** agricultural villages as cultural heritage sites is one way of preserving them for the *** villages can be influenced by the economic and social situation of a *** safeguard both tangible and intangible cultural traditions,the way that we interpret them is ***-designing elements of the landscape may be necessary for conservation,but it may change the natural environment of a *** paper aims to discuss conservation design in agricultural villages through a case study of the historic villages of Shirakawa-go and Gokayama,which are World Heritage *** Shirakawa mura,there are regulations for the design of landscape *** elements are controlled by regulations and ***-style houses are crucial elements of the design,and each element has a relationship with everyday activities such as agriculture and *** modern times,relationships with nature have become tenuous,and activity in forest areas has *** pass on the traditions and culture of these villages to the next generation,it is important to create new links between each *** agricultural village cannot continue to be lively without *** self-motivation of residents is important for the sustainable development of agricultural villages.

关键词： cultural landscape community Gassho-style houses farmland forest

Numerical analysis of cavitation cloud shedding in a submerged water jet

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Journal of Hydrodynamics 2016年第6期28卷 986-993页

作者： Guoyi PENG 杨从新 Yasuyuki OGUMA seiji SHIMIZU Department of Mechanical Engineering College of Engineering Nihon University School of Energy and Power Engineering Lanzhou University of Technology

Focused on the unsteady behavior of high-speed water jets with intensive cavitation a numerical analysis is performed by applying a practical compressible mixture flow bubble cavitation model with a simplified estimation of bubble radius. The mean flow of two-phase mixture is calculated by unsteady Reynolds averaged Navier-Stokes （URANS） for compressible flow and the intensity of cavitation in a local field is evaluated by the volume fraction of gas bubbles whose radius is estimated with a simplified Rayleigh- Plesset equation according to pressure variation of the mean flow field. High-speed submerged water jet issuing from a sheathed sharp-edge orifice nozzle is treated. The periodically shedding of cavitation clouds is captured in a certain reliability compared to experiment data of visualization observation and the capability to capture the unsteadily shedding of cavitation clouds is demonstrated. The results demonstrate that cavitation takes place near the entrance of nozzle throat and cavitation cloud expands consequentially while flowing downstream. Developed bubble clouds break up near the nozzle exit and shed downstream periodically along the shear layer. Under the effect of cavitation bubbles the decay of core velocity is delayed compared to the case of no-cavitation jet.

关键词： cavitation bubble dynamics submerged water jet two-phase flow turbulent flow