Modeling of The Dynamics of N-Body Tethered Satellite Systems

Yu Ling Yan,A. K. Misra,Naoki Oshiro,Tetsuhiko Yamamoto 대한기계학회 1997 Asia-Pacific Vibration Conference Vol.2 No.1

Experimental trials of Si coating on the surface of municipal solid waste incineration fly ash particles using hydrated silica with sodium hydroxide

( Yu Tian ),( Astryd Viandila Dahlan ),( Giun Jo ),( Takashi Yamamoto ),( Fumitake Takahashi ) 한국폐기물자원순환학회(구 한국폐기물학회) 2018 한국폐기물자원순환학회 심포지움 Vol.2018 No.1

From about 1960, Japan accelerated treatment of urban garbage by incineration. In 2009, there were 1243 incineration facilities for municipal solid wastes (MSW) in Japan. Fly ash from municipal solid waste incinerators (MSWI) contains a lot of heavy metals as well as toxic organic substances. Incineration plants for MSW always equip flue gas treatment devices to remove SOx, HC1, NOx, smoke, dioxin and particulate solid residues in flue gases. The solid particles produced during municipal solid waste incineration (MSWI) in mass burning units may be grouped into bottom ashes (BA) and fly ashes (FA). MSWI fly ash is classified as hazardous waste because high contents of heavy metals and toxic organic compounds are possibly leached to the environment. Therefore, it is necessary to take some immobilization treatment before landfill disposal of fly ash. This research focuses on inorganic treatment for stable immobilization of toxic elements. Because the authors already found secondary mineral formation on the surface of fly ash particles under certain conditions and it was partially effective on physical immobilization of soluble elements, this study tried silicate-based inorganic treatment to promote secondary mineral formations and/or physical silicate coverage on the surface. In this study, fly ash sample was collected from a Japanese MSWI facility plant. Deionized water, hydrated silica (0.01mol/L) and sodium hydroxide (0.01mol/L) were used as inorganic agents to treat the MSWI fly ash. The inorganic agents were mixed with MSWI fly ash at the solid to liquid (L/S) ratio of 1. Moistened samples were dried at room temperature about 20 °C for about 120 hours. Scanning electron microscope (SEM) was used to observe the morphology of fly ash particles. Energy dispersive X-ray spectrometry (EDX) was used to observe the surface elemental concentrations of each fly ash particle. X-ray diffraction analysis (XRD) was used to detect major secondary minerals. According to the measurement results of XRD, the main minerals were sylvite, halite, anhydrite, gypsum, calcite and quartz. By the results of SEM observations and XRD analysis, there is no significant difference between raw and inorganic-treated MSWI fly ash in terms of mineralogical composition. It suggests that inorganic treatment tested in this study was not effective to promote secondary mineral formations which was detectable by XRD. This study also expected physical immobilization of soluble elements by silicate coverage on the surface of fly ash particles. Therefore, the authors focused on Si distribution on fly ash particle surfaces. In order to evaluate homogeneous or heterogeneous Si coverage by hydrated silica, the authors checked certain sections of the surface of MSWI fly ash particles on which high degradation of surface elemental concentration were found by elemental mappings. Especially, chlorine (Cl), calcium (Ca), and silica (Si) were detected in higher concentrations than other sections. When line profiles of elemental concentration variations along target sections were analyzed, large variation of Si compared to Cl and Ca were observed. The results of line profile analysis suggested that sodium silica solution, sodium aluminum or sodium silica was not simply adhered to the particle surface during inorganic treatment. This means that physical immobilization by Si coating would require method modification. At least, simple mixing using hydrated silica solution generates heterogeneous Si coating on the surface of fly ash particles.

Temperature-Resistant Bicelles for Structural Studies by Solid-State NMR Spectroscopy

Yamamoto, Kazutoshi,Pearcy, Paige,Lee, Dong-Kuk,Yu, Changsu,Im, Sang-Choul,Waskell, Lucy,Ramamoorthy, Ayyalusamy American Chemical Society 2015 Langmuir Vol.31 No.4

<P>Three-dimensional structure determination of membrane proteins is important to fully understand their biological functions. However, obtaining a high-resolution structure has been a major challenge mainly due to the difficulties in retaining the native folding and function of membrane proteins outside of the cellular membrane environment. These challenges are acute if the protein contains a large soluble domain, as it needs bulk water unlike the transmembrane domains of an integral membrane protein. For structural studies on such proteins either by nuclear magnetic resonance (NMR) spectroscopy or X-ray crystallography, bicelles have been demonstrated to be superior to conventional micelles, yet their temperature restrictions attributed to their thermal instabilities are a major disadvantage. Here, we report an approach to overcome this drawback through searching for an optimum combination of bicellar compositions. We demonstrate that bicelles composed of 1,2-didecanoyl-<I>sn</I>-glycero-3-phosphocholine (DDPC) and 1,2-diheptanoyl-<I>sn</I>-glycero-3-phosphocholin (DHepPC), without utilizing additional stabilizing chemicals, are quite stable and are resistant to temperature variations. These <I>temperature-resistant bicelles</I> have a robust bicellar phase and magnetic alignment over a broad range of temperatures, between −15 and 80 °C, retain the native structure of a membrane protein, and increase the sensitivity of solid-state NMR experiments performed at low temperatures. Advantages of two-dimensional separated-local field (SLF) solid-state NMR experiments at a low temperature are demonstrated on magnetically aligned bicelles containing an electron carrier membrane protein, cytochrome <I>b</I><SUB>5</SUB>. Morphological information on different DDPC-based bicellar compositions, varying <I>q</I> ratio/size, and hydration levels obtained from <SUP>31</SUP>P NMR experiments in this study is also beneficial for a variety of biophysical and spectroscopic techniques, including solution NMR and magic-angle-spinning (MAS) NMR for a wide range of temperatures.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/langd5/2015/langd5.2015.31.issue-4/la5043876/production/images/medium/la-2014-043876_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/la5043876'>ACS Electronic Supporting Info</A></P>

Preliminary observations of surface morphology of municipal solid waste incineration fly ash particles treated by sodium carbonate, sulfate, and phosphate

( Yu Tian ),( Hiroki Kitamura ),( Astryd Viandila Dahlan ),( Takashi Yamamoto ),( Fumitake Takahashi ) 한국폐기물자원순환학회(구 한국폐기물학회) 2017 한국폐기물자원순환학회 심포지움 Vol.2017 No.1

Municipal solid wastes incineration (MSWI) is a commonly accepted solution in Japan for waste management by municipalities. The main products after incineration are bottom ash (BA) and fly ash (FA). The fly ash is cargorized as hazardous waste owing to high contents of heavy metals and toxic organic compounds like dioxin. It is necessary to take some immobilization treatment before landfill disposal of fly ash. The major treatment method in Japan is organic treatments such as chelating treatment. In this process, the authors found secondary mineral formations on fly ash surfaces. Because chelate reagents for organic treatment can be decomposed within several years and cause high concentraions of organic carbon in landfill leachate, this research focuses on inorganic treatments for stable immobilize of toxic elements. In this study, MSWI fly ash sample was collected from a Japanese MSWI facility plant. Materials used in this research are chelate-treated MSWI fly ash, and three kinds of inorganic reagents. They are sodium carbonate (0.01mol/L), sodium phosphate (0.01mol/L) and sodium sulfate (0.01mol/L). In organic treatment, sodium solutions were mixed with fly ash at the solid to liquid (L/S) ratio of 1. Moistened samples were dried at room temperature about 20 °C for about 5 days. X-Ray Diffraction (XRD) method was used to detect major secodaiy minerals. Scanning Electron Microscope (SEM) was used to observe the surface morphology of fly ash particles and Energy Dispersive X-Ray analyzer (EDX) equipped with SEM was used to measure elemental distribtuions of fly ash particle surfaces. According to the experiment results of XRD, the main crystals were sylvite, halite, anhydrite, gypsum, calcite and quartz. There is no significant difference bteween raw and inorganic-treated MSWI fly ash. It suggests that inorganic treatment did not promote secondary mineral formations which were detecable by XRD. SEM-EDX analysis showed that raw, chelate-treated and inorganic-treated MSWI fly ash particles consist mainly of Na, K, Cl, Ca, Al, and Si. According to SEM observations, significant differences of surface morphology of fly ash after inorganic treatment were not found in spite of chelate-treated MSWI fly ash. Although inomgaic treatments were expected to promote the formations of calcite (CaCO₃), gypsum (CaSO₄·2H₂O) and apatite (Ca₅(PO₄)₃(OH)₂), experimental conditions should be improved in particular water content, pH, and reaction time.

Characteristics of Voltage Sag/Swell Compensator Utilizing Single-Phase Matrix Converter

Yamamoto, Kichiro,Ikeda, Keisuke,Tsurusaki, Yu,Ikeda, Minoru Journal of International Conference on Electrical 2013 Journal of international Conference on Electrical Vol.2 No.4

Compensating characteristics of a voltage sag/swell compensator utilizing single-phase matrix converter is examined. First, system configuration and operation for both voltage sag and swell are described. Next, in order to suppress pulsations of the source voltage, a countermeasure using low pass filter and all pass filter is introduced. Then, compensating characteristics of the compensator are investigated for R-L load by simulation. Finally, the validity of the simulated results is confirmed by the experimental results.

Fast electro-optic device controlled by dielectric response of planarly aligned cholesteric liquid crystals

Lee, Ho Hyun,Yu, Jeong-Seon,Kim, Jong-Hyun,Yamamoto, Shin-ichi,Kikuchi, Hirotsugu American Institute of Physics 2009 JOURNAL OF APPLIED PHYSICS - Vol.106 No.1

A first modern contribution to <i>Caloplaca</i> biodiversity in South Korea: two new species and some new country records

JOSHI, Yogesh,WANG, Xin Yu,YAMAMOTO, Yoshikazu,KOH, Young Jin,HUR, Jae-Seoun Cambridge University Press 2010 The Lichenologist Vol.42 No.6

<B>Abstract</B><P>Eleven species are recognized of which <I>C. bogilana</I> and <I>C. subflavorubescens</I> are described here as new to science while nine species (<I>C. cinnabarina</I>, <I>C. decipiens</I>, <I>C. ferruginea</I>, <I>C. inconspecta</I>, <I>C. pellodella</I>, <I>C. scopularis</I>, <I>C. stantonii</I>, <I>C. squamosa</I> and <I>C. subsoluta</I>) are reported for the first time for South Korea. Both new species are peculiar due to their secondary chemistry; anthraquinones along with atranorin, gyrophoric acid and lecanoric acid in <I>C. bogilana</I>, and gyrophoric acid together with anthraquinones in <I>C. subflavorubescens</I>.</P>

Clock gene mouse period2 overexpression inhibits growth of human pancreatic cancer cells and has synergistic effect with cisplatin.

Oda, Akira,Katayose, Yu,Yabuuchi, Shinichi,Yamamoto, Kuniharu,Mizuma, Masamichi,Shirasou, Satoru,Onogawa, Toru,Ohtsuka, Hideo,Yoshida, Hiroshi,Hayashi, Hiroki,Rikiyama, Toshiki,Kim, Hyunjung,Choe, You Potamitis Press 2009 Anticancer research Vol.29 No.4

<P>Circadian rhythms are the daily oscillations of multiple biological processes regulated by an endogenous clock. The Period2 gene is essential in controlling the circadian rhythm and plays an important role in tumor suppression. We examined whether the overexpression of the mouse Period2 gene (mPer2) in cultured tumor cells from human tissues inhibits cell growth, using the recombinant adenovirus vector AdmPer2. The overexpression of mPer2 in human pancreatic cancer cells (Panc1, Aspc1) reduced cellular proliferation and induced apoptotic cell death. Infection with AdmPer2 also inhibited cell-cycle progression, inducing arrest at the G(2)-M phase. Western blotting analyses confirmed that infection with AdmPer2 reduced Bcl-X(L), Cdc2 and cyclin B1 protein, whereas it increased Bax protein in Aspc1 cells. The overexpression of mPer2 suppressed Cdc2 kinase activity. Moreover, infection with AdmPer2 resulted in dose-dependent synergic cell killing effects with the anticancer agent cisplatin (CDDP) in human pancreatic cancer cells. This synergic effect might be related to the reduction of Bcl-X(L) induced by infection with AdmPer2. Our results suggest that the circadian gene Period2 may play an important role in suppression of cell proliferation in human cancer, and additionally Period2 gene expression level may influence the sensitivity to cisplatin depending on Bcl-X(L) expression level.</P>

Interparticle elemental heterogeneity of surface and insoluble inner matrices of municipal solid waste incineration fly ash particles: A comparison between stoker incinerator and fluidized bed incinerator

( Astryd Yiandila Dahlan Hiroki Kitamura ),( Yu Tian ),( Hirofumi Sakanakura ),( Takashi Yamamoto ),( Fumitake Takahashi ) 한국폐기물자원순환학회(구 한국폐기물학회) 2018 한국폐기물자원순환학회 심포지움 Vol.2018 No.1

Incineration is major treatment method of municipal solid waste (MSW) in Japan to reduce volume and weight of the waste. In 2016, total MSW generation in Japan was about 43.17 million tons and around 80 % of MSW were combusted by incinerators. Bottom ash and fly ash are the main products from MSW incinerators. MSW incineration fly ash is categorized as hazardous waste due to high concentration of leachable toxic heavy metals and the presence of toxic organic compounds like dioxins. Although MSWI fly ash is fine particles and has been regarded as homogeneous in numerous previous researches, it has not been proved based on sufficient analysis in the micro-scale. Therefore, the objective of the study is to investigate particle-scale heterogeneity of fly ash, in particular heterogeneity among fly ash particles (interparticle heterogeneity). In this study, fly ash generated from a fluidized bed and stoker combustor were analyzed and compared. Surface elemental concentrations of each fly ash particles, measured by SEM-EDS, were used to analyze elemental heterogeneity among fly ash particles. In order to measure interparticle heterogeneity of inner matrices of fly ash particles, Japan leaching test 19th (JLT 19), which used hydrochloric acid as leaching medium with liquid-to-solid ratio of 33.3, were conducted to remove semi-soluble and soluble components of fly ash particles. For each sample of stoker incinerator fly ash, fluidized bed incinerator fly ash, and their insoluble residues of JLT 19, 100 particles were measured. Elemental binary molar ratio among Ca, Si and A1 were plotted in ternary diagrams to visualize interparticle heterogeneity. Major elements in fly ash particles generated from both incinerators have large distributions of elemental concentrations. On the other hand, there are not significant differences of elemental concentration distribution between both incinerator fly ash excluding calcium (Ca). Ca concentration in fluidized bed combustor is relatively higher than stoker combustor. Ca concentration distribution of fluidized bed incinerator fly ash is wider than that of stoker combustor fly ash. Elemental ratios among Ca, Si and Al, plotted in triangular graphs, clearly shows that fly ash particles produced from stoker combustor concentrated in Ca area. On the other hand, fly ash of fluidized bed incinerator are dispersed more to Ca and Si sides as shown in Figure 1. This means that fly ash of fluidized bed incinerator has larger interparticle elemental heterogeneity compared to stoker combustor fly ash although different waste streams might have caused this difference to some extent. Fly ash residues of JLT 19 are relatively concentrated in Si area compared to fly ash particle surfaces. The authors expected that most of residue samples would be plotted near Si area. However, some particles spread to Ca and A1 areas. Moreover, fly ash of stoker incinerator has more scattered plots than fluidized bed incinerator fly ash. In contrast to interparticle elemental heterogeneity on fly ash surfaces, insoluble inner matrices of stoker incinerator fly ash have larger interparticle heterogeneity than fluidized bed incinerator fly ash. These analysis results would be useful for not only evaluation of fly ash heterogeneity but also considerations of fly ash formation mechanisms.

Hyperfractionated radiotherapy for re-irradiation of recurrent esophageal cancer

Kazuya Takeda,Haruo Matsushita,Rei Umezawa,Takaya Yamamoto,Yojiro Ishikawa,Noriyoshi Takahashi,Yu Suzuki,Keiichi Jingu 대한방사선종양학회 2021 Radiation Oncology Journal Vol.39 No.4

Purpose: Re-irradiation is a treatment option for recurrent esophageal cancer patients with a history of radiotherapy, but there is a risk of severe late adverse effects. This study focused on the efficacy and safety of re-irradiation using hyperfractionated radiotherapy. Materials and Methods: Twenty-six patients who underwent re-irradiation by the hyperfraction technique using twice-daily irradiation of 1.2 Gy per fraction for recurrent esophageal cancer were retrospectively included in this study. The overall survival period after the start of secondary radiotherapy and the occurrence of late adverse effects were investigated. Results: Of 26 patients, 21 (81%) received re-irradiation with definitive intention and 21 (81%) underwent concurrent chemotherapy. The median re-irradiation dose was 60 Gy in 50 fractions in 25 treatment days, and the median accumulated irradiation dose in equivalent dose in 2 Gy per fraction was 85.4 Gy with an α/β value of 3. The median interval between two courses of radiotherapy was 21.0 months. The median overall survival period was 15.8 months and the 1-year and 3-year overall survival rates were 64.3% and 28.3%, respectively. Higher dose of re-irradiation and concurrent chemotherapy significantly improved survival (p < 0.001 and p = 0.019, respectively). Severe late adverse effects with the Common Terminology Criteria for Adverse Events grade 3 or higher were observed in 5 (19.2%) patients, and 2 (7.7%) of them developed a grade 5 late adverse effect. Conclusion: High-dose re-irradiation using a hyperfractionated schedule with concurrent chemotherapy might be related to good prognosis, while the rate of late severe adverse effects is not high compared with the rates in past reports.