Neutron spin-echo (NSE) measurements have been performed on three types ofpoly (vinyl alcohol)(PVA) gels;two physical gels and one chemical gel.The first onewas a PVA gel in a mixture of deuterated dimethyl sulfoxide (DMSO-d₆) and D₂O withvolume fraction of DMSO-d₆being0.6, in which cross-links are made of crystallites.On the basis of NSE results, small-angle neutron scattering (SANS) intensity wasdivided into static and dynamic fluctuations to find that the static fluctuations weredominant in the present Q range.The dynamic fluctuations are analyzed in terms offluctuations of cross-links in the quasi-equilibrium position.The second one was PVAin aqueous borax solution.The intermediate scattering functions of the gel as well asthe sol were well described by the Zimm mode and the gel mode in Q regions of aboveand below a critical Q_c.The last one was the chemically cross-linked PVA gel.Theintermediate scattering function was also described by Zimm mode in a short-timeregion, suggesting that the gel behaves like sol. However, in a long-time region, thedata points deviated from Zimm function, suggesting that the long-time dynamics wasrestricted by the cross-links made of covalent bonds.

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Superconductivity has been discovered around 50 K in FeSr₂YCu₂O_6+δ, when it isproperty annealed in N₂ atmosphere and subsequently in O₂ atmosphere.Neutronpowder diffraction study shows that N₂-annealing causes atomic ordering of Cu and Feto avoid the substitution of Fe for Cu on the CuO₂ sheet, and that 0₂-annealing andsubsequent oxidizing under high-0₂ pressure supply the carrier on the CuO₂ sheets toexhibit superconductivity. We also observed orthorhombic phase with the FeO₄tetrahedron, which is necessary to the atomic ordering of Cu and Fe.

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A novel type of cold-neutron interferometer has been developed. It contains a pair ofnew devices named‘beam splitting etalons (BSEs), ’which enable us to align fourindependent multilayer mirrors in the interferometer within required precision. In thispaper the recent progress of the interferometer using etalons will be reported. Thefuture prospect of some applications for fundamental physics will be also discussed.

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ISSP-NSE was relocated from the C2-2 port to the guide end of the C2 beam line in the JRR-3M, JAERI.On this process, we decided to use a polymeric floor instead of the othertype of floors, such as stone floors. The requirements for the floor are its hardness to sustainthe weight of the spectrometer, its flatness to ensure smooth movement, its area (above40m²) to get a wide scattering angle range, and so on. The present polymeric floor is enoughhard to set the spectrometer, and the level of the floor showed the flatness within 100μm forthe whole floor regions of 42m². The NSE spectrometer moves smoothly from 0 to 98degree of the scattering angle.The new floor shows very good performances as a dancingfloor of the spectrometer as well as the level surface to put the heavy shielding on.

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A new epithermal neutron diffractormeter EXCED has been in operation at KENS neutronfacility in order to investigate the materials containing highly neutron absorbing atoms suchas gadolinium, boron, cadmium, silver and so forth.The pulsed neutrons combined with Time-Of-Flight (TOF) technique demonstrated reasonable diffractions with good Q resolutions in spite of the disadvantage of small-angle scattering.

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Computing environments design of Material and Life Science Facility at J-PARC wasdescribed.Since it is necessary to use computers to handle large size datasets, thecomputing environments should be designed to be a good tool for researchers. MLFcomputing environment design group launched at April 2003 and design works has beenpreceded based on simple component model including a security system. Developments ofdata analysis codes, data acquisition and experiment control software are on going.Minimum system should be prepared by the first beam on the way to realize the “ideal” computing environment.

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