The perception of Arabic and Japanese short and long vowels by native speakers of Arabic, Japanese, and Persian

This study examines the perception of short and long vowels in Arabic and Japanese by three groups of listeners differing in their first languages (L1): Arabic, Japanese, and Persian. While Persian uses the same alphabet as Arabic and Iranian students learn Arabic in school, the two languages are typologically unrelated. Further, unlike Arabic or Japanese, vowel length may no longer be contrastive in modern Persian. In this study, a question of interest was whether Persian listeners' foreign language learning experience or Japanese listeners' L1 phonological experience might help them to accurately process short and long vowels in Arabic. In Experiment 1, Arabic and Japanese listeners were more accurate than Persian listeners in discriminating vowel length contrasts in their own L1 only. In Experiment 2, Arabic and Japanese listeners were more accurate than Persian listeners in identifying the length categories in the "other" unknown language as well as in their own L1. The difference in the listeners' perceptual performance between the two experiments supports the view that long-term L1 representations may be invoked to a greater extent in the identification than discrimination test. The present results highlight the importance of selecting the appropriate test for assessing cross-language speech perception.     

Study of γ d → π + π − d Reaction in an Energy Region of 0.67 ≤ E γ ≤ 1.08 GeV

Double charged pion photoproductions from the deuteron have been studied at Research Center for Electron Photon Science (ELPH), Tohoku University. Tagged photon beams in an energy range of 0.67 ≤ E _γ ≤ 1.08 GeV were impinged on the liquid deuteron target. Produced charged particles were observed with the Neutral Kaon Spectrometer2 (NKS2). The γ d → π ⁺ π ^? d process was clearly separated among the three charged tracks. We obtained the photon energy dependence of the normalized yields of this process.     

Crystal structure and mixed-valence state in 1′,1‴-dibutylbiferrocenium triiodide

In 1′, 1‴-dibutylbiferrocenium triiodide crystals A show temperature-independent trapped-valence state, while crystals B show a valence-delocalization of the mixed-valence state. The mixed-valence states of both crystals are discussed in relation to their crystal structures. Address after October 1991: Department of Chemistry, Faculty of Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima 724, Japan     

Heavy element nuclear chemistry at JAERI

The present status of heavy element nuclear chemistry research at JAERI (Japan Atomic Energy Research Institute) is reviewed. Production of the transactinide nuclei ²⁶¹Rf and ²⁶²Db via the reactions of ²⁴⁸Cm(¹⁸O,5n) and ²⁴⁸Cm(¹⁹F, 5n), respectively, at the JAERI tandem accelerator is reported. Study of the aqueous chemistry of Rf is being carried out with a newly developed rapid ion-exchange separation apparatus. Anion-exchange behavior of Rf in acidic solution is briefly discussed. Recent experimental results on decay studies of neutron-deficient actinide nuclei using the gas-jet coupled JAERI-ISOL are given. We also discuss characteristics of nuclear deformation properties at scission in symmetric and asymmetric fission of actinides. Prospects for studies in the near future are briefly considered.     

Observation of the transient rotator phase of n-hexadecane in emulsified droplets with time-resolved two-dimensional small- and wide-angle X-ray scattering

Crystallization of n-hexadecane in emulsion droplets was studied using time-resolved two-dimensional small- and wide-angle x-ray scattering with differential scanning calorimetry (2D-SAXS-WAXS-in situ DSC) which provides information about both nano- and subnanoscale structural change. n-hexadecane in droplets reproducibly crystallized into the stable triclinic phase via a transient-rotator phase. This is in contrast with previous results that the rotator phase of n-hexadecane was observed only occasionally for bulk samples. Thus we confirmed the existence of rotator phase in n-hexadecane, which is important for the study of crystallization of soft materials. We suggest that the rotator phase at the interface of oil and water plays a precursor role for bulk crystallization. This study demonstrates that 2D-SAXS-WAXS-in situ DSC is a powerful tool for the study of a transient phase.     

Measurement Accuracy in Phase-Shifting Point Diffraction Interferometer with Two Optical Fibers

A phase-shifting point diffraction interferometer (PS/PDI) with point sources of two single mode optical fibers has been developed, which will be appropriate for the surface figure measurement of large aperture optics on a sub-nanometer scale. To reduce the measurement error factors, a fiber optic plate (FOP) is used as a projection plane for interference pattern. Errors caused by imperfection of optical alignment, such as position of point sources and tilt of FOP, are minimized by analyzing the measured phase data with an original method. Measurement accuracy in the PS/ PDI is estimated with the interference pattern produced by the two optical fiber sources. If inhomogeneity of the FOP and a systematic error of the PS/PDI are eliminated, the measurement accuracy of the present system is estimated to be less than 4nm P-V and 0.7nm rms, respectively, at a measurement wavelength of 632.8 nm.     

Qβ measurements of 158, 159Pm , 159, 161Sm , 160-165Eu , 163Gd and 166Tb using a total absorption BGO detector

Q _β values of the neutron-rich isotopes of ^160-165Eu and ¹⁶³Gd were measured for the first time using a total absorption bismuth germanate (BGO) detector, and previously obtained data on ^{158, 159}Pm , ^{159, 161}Sm and ¹⁶⁶Tb were re-analyzed. These radioactive sources were prepared by an on-line mass separator (Tokai-ISOL) following the ²³⁸U (p,f reaction. The deduced Q _β values are the following: 6085(80)keV for ¹⁵⁸Pm , 3805(65)keV for ¹⁵⁹Sm , 5460(140)keV for ¹⁵⁹Pm , 4705(60)keV for ¹⁶⁰Eu , 5065(130)keV for ¹⁶¹Sm , 3705(60)keV for ¹⁶¹Eu , 5575(60)keV for ¹⁶²Eu , 4690(70)keV for ¹⁶³Eu , 3170(70)keV for ¹⁶³Gd , 6430(70)keV for ¹⁶⁴Eu , 5800(120)keV for ¹⁶⁵Eu , and 4695(70)keV for ¹⁶⁶Tb . Moreover, the deduced mass excesses and two-neutron separation energies ( S _2n values) were compared with those of the atomic mass evaluations and theoretical predictions.     

Construction of self-assembled monolayer terminated with N-heterocyclic carbene-rhodium(I) complex moiety

Functionalization of self-assembled monolayer (SAM) of alkanethiolate with metal containing unit is one of the versatile methods to obtain functional surfaces such as heterogeneous catalysts. However, organic molecules that strongly bind to transition metals at SAM terminal are limited. Recently N-heterocyclic carbenes (NHCs) such as cyclic diaminocarbenes have emerged as strongly σ-donating ligands forming a robust bond with broad spectrum of transition metals. In the present study, for the purpose of establishment of a new robust basement for heterogeneous metal catalysts, a SAM of the alkanethiolate terminated with NHC-rhodium(I) complex moiety was prepared by utilizing a newly designed disulfide molecule bearing NHC-metal complex terminals. X-ray photoelectron spectroscopy (XPS) analysis and angle resolved XPS measurement revealed successful formation of the Rh-complex-terminated SAM on a gold substrate. Infrared reflection absorption spectroscopy (IRRAS) analysis suggested that the linker methylene chains connecting the rhodium complex moiety and the gold surface are in a loosely packed structure. This unique chemical species, NHC, would be a promising candidate as a basement for the construction of functional surface.