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951.
The fundamental frequencies (F0) of daily life utterances of Japanese infants and their parents from the infant's birth until about 5 years of age were longitudinally analyzed. The analysis revealed that an infant's F0 mean decreases as a function of month of age. It also showed that within- and between-utterance variability in infant F0 is different before and after the onset of two-word utterances, probably reflecting the difference between linguistic and nonlinguistic utterances. Parents' F0 mean is high in infant-directed speech (IDS) before the onset of two-word utterances, but it gradually decreases and reaches almost the same value as in adult-directed speech after the onset of two-word utterances. The between-utterance variability of parents' F0 in IDS is large before the onset of two-word utterances and it subsequently becomes smaller. It is suggested that these changes of parents' F0 are closely related to the feasibility of communication between infants and parents. 相似文献
952.
Toshiyuki Tamai Mitsuru Watanabe Tomohiro Teramura Noboru Nishioka Kimihiro Matsukawa 《Macromolecular Symposia》2009,282(1):199-204
Summary: Polymer particles decorated with metal nanoparticles were prepared by UV-irradiation of polystyrene particles incorporating polymethylphenylsilane (PS/PMPS) and P[S-co-NIPAM]/PMPS particles (NIPAM: N-isopropyl acrylamide) in the presence of metal salts. The metal nanoparticle/polymer hybrid particles were used as a catalyst for the reduction of 4-nitrophenol with NaBH4. The Pd- and Ag-P(S-co-NIPAM)/PMPS hybrid particles had larger metal nanoparticles and the lower catalytic activity than those of Pd- and Ag-PS/PMPS, respectively. The surface functional group of the polymer particles affected the formation of the metal nanoparticles and their catalytic activity. 相似文献
953.
Dr. Tomohiro Higashino Hitomi Iiyama Yuma Kurumisawa Prof. Dr. Hiroshi Imahori 《Chemphyschem》2019,20(20):2689-2695
Anchoring groups adopting a five-membered bidentate chelating are attractive to realize high power conversion efficiency (η) and long-term durability in dye-sensitized solar cells (DSSCs). In this regard, we chose catechol as an anchoring group that can adopt the chelating. However, the DSSCs with catechol-based sensitizers have never exceeded an η-value of 2 %. These poor photovoltaic performances may be associated with the electron-donating ability of the hydroxy groups in catechol. Considering these, we envisioned that fusing an electron-withdrawing thiazole moiety with a catechol anchoring group would improve its photovoltaic performance. Herein, we report a push-pull porphyrin sensitizer ZnPTC with a thiazolocatechol anchoring group. The DSSC with ZnPTC exhibited η=4.87 %. This value is the highest ever reported for catechol-anchor based DSSCs. Meanwhile, the long-term cell durability was not improved, although the robust anchoring properties were attained under harsh conditions. 相似文献
954.
Koshiro Midori Tomohiro Fukuhara Dr. Yasunari Tamai Dr. Hyung Do Kim Prof. Hideo Ohkita 《Chemphyschem》2019,20(20):2683-2688
Recently, ternary blend polymer solar cells have attracted great attention to improve a short-circuit current density (JSC) effectively, because complementary absorption bands can harvest the solar light over a wide wavelength range from visible to near-IR region. Interestingly, some ternary blend solar cells have shown improvements not only in JSC but also in fill factor (FF). Previously, we also reported that a ternary blend solar cell based on a low-bandgap polymer (PTB7-Th), a wide-bandgap polymer (PDCBT), and a fullerene derivative (PCBM) exhibited a higher FF than their binary analogues. Herein, we study charge transport in PTB7-Th/PDCBT/PCBM ternary blend films to address the origin of the improvement in FF. We found that hole polarons are located in PTB7-Th domains and their mobility is enhanced in the ternary blend film. 相似文献
955.
Kanae Sano Taiki Kuribara Nozomi Ishii Ayumi Kuroiwa Toshitada Yoshihara Seiji Tobita Kiichiro Totani Ichiro Matsuo 《化学:亚洲杂志》2019,14(11):1965-1969
Golgi endo‐α‐mannosidase (G‐EM) catalyzes an alternative deglucosylation process for N‐glycans and plays important roles in the post‐endoplasmic reticulum (ER) quality control pathway. To understand the post‐ER quality control mechanism, we synthesized a tetrasaccharide probe for the detection of the hydrolytic activity of G‐EM based on a fluorescence quenching assay. The probe was labeled with an N‐methylanthraniloyl group as a reporter dye at the non‐reducing end and a 2,4‐dinitrophenyl group as a quencher at the reducing end. This probe is hydrolyzed to disaccharide derivatives by G‐EM, resulting in increased fluorescence intensity. Thus, the fluorescence signal is directly proportional to the amount of disaccharide derivative present, allowing the G‐EM activity to be evaluated easily and quantitatively. 相似文献
956.
Let : X
T be a small deformation of a normal
Gorenstein surface singularity
X
0 =
-1(0) over the complex number field .
Suppose that T is a neighborhood
of the origin of and that
X
0
is not log-canonical.
We show that if a topological invariant
-P
t
P
t
of X
t
= -1(t)
is constant, then, after a suitable finite base change,
admits a simultaneous resolution
f : M
X which induces a locally trivial
deformation of each maximal string of rational curves at an end of
the exceptional set of M
0
X
0;
in particular, if X
0
has a star-shaped resolution graph, then
admits a weak simultaneous resolution (in other words, is
an equisingular deformation). 相似文献
957.
Grinding a 1 : 1 enantiomeric mixture of chiral transition metal complex crystals and subsequent annealing afforded crystals of a racemic compound by diffusion and rearrangement of component molecules, without melting and without racemization of each enantiomeric species. 相似文献
958.
Goto T Maeda K Yoshida Y 《Langmuir : the ACS journal of surfaces and colloids》2005,21(25):11788-11794
Cyclic voltammograms and interfacial tension-applied potential curves were recorded at the interface between water containing surface-active bis-quaternary ammonium ions, bis-A(2+), and an organic solvent such as 1,2-dichloroethane or nitrobenzene. An ordinary diffusion-controlled voltammetric wave for the transfer of bis-A(2+) from aqueous phase to organic phase, the first wave, was followed by a typical adsorption-related wave, the second wave. It was found from the potential dependence of the interfacial tension of bis-A(2+) that the second wave was due to the desorption of bis-A(2+) toward the organic phase. The influence of the structure of bis-A(2+) on voltammograms was investigated, and the potential for the first wave was found to depend on both the length of the side chain and that of the spacer chain, whereas the potential for the second wave depended on the latter only. The thermodynamic relations among three processes of the ion transfer, adsorption, and desorption were discussed based on the experimental results. 相似文献
959.
In string theory, stabilization of moduli fields and their cosmological implications have been discussed by many authors. In this paper, we consider the relative positions of three intersecting branes. Surprisingly, there had been no phenomenological and cosmological argument on the mechanism that stabilizes the corresponding parameter. We show that the area of the triangle is not a free parameter. The effective potential is generated from loop corrections in the low energy effective Lagrangian, where supersymmetry is expected to be broken. The stabilization of the area of such triangles will determine the Yukawa couplings that have been considered as the free parameters of the intersecting brane models. The stabilization puts a constraint on the model, which is different from the other requirements that have been discussed before. We also discuss cosmological problems and then show an idea that may solve the problem. 相似文献
960.
Hayashi Y Gotoh H Tamura T Yamaguchi H Masui R Shoji M 《Journal of the American Chemical Society》2005,127(46):16028-16029
Asymmetric intramolecular Michael reaction catalyzed by an organocatalyst derived from cysteine has been developed for the synthesis of chiral bicyclo[4.3.0]nonene and cis-disubstituted cyclopentane skeletons with a creation of three or two contiguous chiral centers in good yield with high diastereo- and excellent enantioselectivities. 相似文献