Scanning tunneling microscopy images for two isomers of Ce@C-82 were observed on Si(111)-(7x7) at 295 K. The Ce@C-82 molecules in the first layer were bound to the Si surfaces, and the motions were frozen even at 295 K. The multilayer of the Ce@C-82 isomer I (Ce@C-82-I) produced a close-packed structure in the surface layer by annealing the Si substrate at 473 K. The distance between the nearest-neighboring molecules was 1.15(4) nm whose value was consistent with that, 1.12 nm, estimated from x-ray diffraction of the Ce@C-82-I crystals. This implies that the close-packed structure is dominated by van der Waals forces, as in crystals of Ce@C-82-I. The internal structure of Ce@C-82-I was observed in the first layer due to a freeze of molecular motion caused by strong interactions between the molecule and the Si adatoms in the surface. Scanning tunneling spectroscopy revealed that the energy gaps for Ce@C-82-I and -II in the first layer opened to gap energies, E-g of 0.7 and 1.0 eV, respectively. This fact suggests that these molecules are semiconductors with smaller value of E-g than those for C-60 and C-70.
en-copyright= kn-copyright= en-aut-name=FujikiSatoshi en-aut-sei=Fujiki en-aut-mei=Satoshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=KubozonoYoshihiro en-aut-sei=Kubozono en-aut-mei=Yoshihiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=RikiishiYoshie en-aut-sei=Rikiishi en-aut-mei=Yoshie kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=UrisuTsuneo en-aut-sei=Urisu en-aut-mei=Tsuneo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=Graduate University for Advanced Studies affil-num=2 en-affil= kn-affil=Science and Technology Agency affil-num=3 en-affil= kn-affil=Okayama University affil-num=4 en-affil= kn-affil=Graduate University for Advanced Studies en-keyword=electronic-structure kn-keyword=electronic-structure en-keyword=endohedral metallofullerenes kn-keyword=endohedral metallofullerenes en-keyword=microscopy kn-keyword=microscopy en-keyword=lanthanum kn-keyword=lanthanum en-keyword=crystal kn-keyword=crystal en-keyword=anion kn-keyword=anion en-keyword=films kn-keyword=films END start-ver=1.4 cd-journal=joma no-vol=122 cd-vols= no-issue=7 article-no= start-page= end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2005 dt-pub=20050215 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=On the thermodynamic stability and structural transition of clathrate hydrates en-subtitle= kn-subtitle= en-abstract= kn-abstract=Gas mixtures of methane and ethane form structure II clathrate hydrates despite the fact that each of pure methane and pure ethane gases forms the structure I hydrate. Optimization of the interaction potential parameters for methane and ethane is attempted so as to reproduce the dissociation pressures of each simple hydrate containing either methane or ethane alone. An account for the structural transitions between type I and type II hydrates upon changing the mole fraction of the gas mixture is given on the basis of the van der Waals and Platteeuw theory with these optimized potentials. Cage occupancies of the two kinds of hydrates are also calculated as functions of the mole fraction at the dissociation pressure and at a fixed pressure well above the dissociation pressure. en-copyright= kn-copyright= en-aut-name=KoyamaYuji en-aut-sei=Koyama en-aut-mei=Yuji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=TanakaHideki en-aut-sei=Tanaka en-aut-mei=Hideki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=KogaKenichiro en-aut-sei=Koga en-aut-mei=Kenichiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=Department of Chemistry, Faculty of Science, Okayama University affil-num=2 en-affil= kn-affil=Department of Chemistry, Faculty of Science, Okayama University affil-num=3 en-affil= kn-affil=Department of Chemistry, Faculty of Science, Okayama University en-keyword=STRUCTURE-II kn-keyword=STRUCTURE-II en-keyword=POTENTIAL FUNCTIONS kn-keyword=POTENTIAL FUNCTIONS en-keyword=ETHANE kn-keyword=ETHANE en-keyword=METHANE kn-keyword=METHANE en-keyword=GAS kn-keyword=GAS en-keyword=MOLECULES kn-keyword=MOLECULES en-keyword=MIXTURES kn-keyword=MIXTURES en-keyword=PROPANE kn-keyword=PROPANE en-keyword=WATER kn-keyword=WATER END start-ver=1.4 cd-journal=joma no-vol=55 cd-vols= no-issue=1 article-no= start-page= end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2008 dt-pub=20080314 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Modelling the dynamics and control of Schistosoma japonicum transmission on Bohol island, the Philippines en-subtitle= kn-subtitle= en-abstract= kn-abstract=We have investigated a mathematical model for the transmission of Schistosoma japonicum in the infested region of northeastern Bohol island in the Philippines. The development of transmission models is important for planning control strategies. Since S. japonicum has a complicated mode of transmission, the rates of transmission among its hosts cannot be measured directly by field observation. Instead, they have been estimated through model analysis. The model takes into account the seasonal variations and includes a function of control measures. In 1981, a project to eliminate schistosomiasis started on Bohol island. The prevalence decreased dramatically and has kept low level less than 1%. The simulations based on the model predicted that there is little probability of resurgence of an epidemic in the northeastem endemic villages of Bohol island due to the fact that the project has attained a high coverage of selective mass treatment based oil stool examination accompanied by a successful snail control operation. (c) 2005 Elsevier Ireland Ltd. All rights reserved.
en-copyright= kn-copyright= en-aut-name=IshikawaHirofumi en-aut-sei=Ishikawa en-aut-mei=Hirofumi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=OhmaeHiroshi en-aut-sei=Ohmae en-aut-mei=Hiroshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=PangilinanRogelio en-aut-sei=Pangilinan en-aut-mei=Rogelio kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=RedullaApolinario en-aut-sei=Redulla en-aut-mei=Apolinario kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=MatsudaHajime en-aut-sei=Matsuda en-aut-mei=Hajime kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= affil-num=1 en-affil= kn-affil=Okayama University affil-num=2 en-affil= kn-affil=National Institute of Infectious Diseases affil-num=3 en-affil= kn-affil=Schistosomiasis Control Team affil-num=4 en-affil= kn-affil=Schistosomiasis Control Team affil-num=5 en-affil= kn-affil=Dokkyo University School of Medicine en-keyword=schistosomiasis japonica kn-keyword=schistosomiasis japonica en-keyword=control kn-keyword=control en-keyword=mathematical model kn-keyword=mathematical model en-keyword=Philippines kn-keyword=Philippines en-keyword=Bohol kn-keyword=Bohol END