To clarify the target cells of GnRH in the ovary, in vivo expression of ovarian GnRH receptor mRNA was examined histologically by in situ hybridization in immature rats treated with PMSG only or in ...combination with hCG. Strong hybridization signals were observed in the granulosa cells of atretic follicles. However, no significant signals were found in the granulosa cells of healthy small, preantral, or early antral follicles. Healthy Graafian and preovulatory follicles also showed intense signals in their mural granulosa cells, but no signals were detected in the cumulus oophorus cells. Corpora lutea showed only weak signals, but luteinizing follicles probably after atresia exhibited signals of moderate intensity in their luteinized and remaining granulosa cells. No signals were detected in the theca cells and oocytes in all the follicles. Interstitial cells sometimes exhibited hybridization signals of moderate intensity, when the cells were eosinophilic. Pretreatment with different combinations of gonadotropins yielded different ovarian histology, but this had no influence on the localization of hybridization signals. These results, showing that the authentic GnRH receptor mRNA was expressed in a certain cell population in the rat ovary, suggest that the receptor is involved in the control of various ovarian functions including follicular development, atresia, ovulation, and luteinization after ovulation and follicular atresia.
(CuIn) x Zn2(1 - x )S2 solid solutions between a ZnS photocatalyst with a wide band gap and CuInS2 with a narrow band gap showed photocatalytic activities for H2 evolution from aqueous solutions ...containing sacrificial reagents SO3 2- and S2- under visible-light irradiation (λ ≥ 420 nm). Pt (0.5 wt %)-loaded (CuIn)0.09Zn1.82S2 with a 2.3-eV band gap showed the highest activity for H2 evolution, and the apparent quantum yield at 420 nm amounted to 12.5%. H2 evolved at a rate of 1.5 L h-1 m-2 under irradiation with a solar simulator (AM 1.5). Diffuse reflection and photoluminescence spectra of the solid solutions shifted monotonically to a long wavelength side, as the ratio of CuInS2 to ZnS increased in the solid solutions. The photocatalytic H2 evolution depended on the composition as well as the photophysical properties. DFT calculations suggested that the visible-light response should be derived from the contribution of Cu 3d and S 3p orbitals to the valence band and that of In 5s5p and Zn 4s4p orbitals to the conduction band, respectively. The contribution of these orbitals to the energy bands affected the photophysical and photocatalytic properties.
The electrochemical reduction of CO
2 under high pressure in an aqueous solution at metal electrodes with high overpotentials for hydrogen evolution such as Pb, Hg and In was studied. When the ...electrolysis was conducted under high pressure CO
2, HCOOH was formed with faradaic efficiencies of almost 100%, even at high current densities (∼ 200 mA cm
−2). The maximum partial current density of HCOOH formation amounted to 560 mA cm
−2 at the In electrodes under 60 atm of CO
2. On the other hand, it was found that CO could form as the main reduction product of CO
2 at Pb and In electrodes, at which HCOOH has previously been believed to be the main product under 1 atm of CO
2. The selectivity for CO formation depended on the electrode potential. The less negative were the potentials, the higher was the faradaic efficiency of CO formation.
(AgIn) x Zn2(1 - x )S2 solid solutions between ZnS photocatalyst with a wide band gap and AgInS2 with a narrow band gap showed photocatalytic activities for H2 evolution from aqueous solutions ...containing sacrificial reagents, SO3 2- and S2-, under visible-light irradiation (λ ≥ 420 nm) even without Pt cocatalysts. Loading of the Pt cocatalysts improved the photocatalytic activity. Pt (3 wt %)-loaded (AgIn)0.22Zn1.56S2 with a 2.3 eV band gap showed the highest activity for H2 evolution, and the apparent quantum yield at 420 nm amounted to 20%. H2 gas evolved at a rate of 3.3 L m-2·h-1 under irradiation using a solar simulator (AM 1.5). The diffuse reflection and the photoluminescence spectra of the solid solutions shifted monotonically to a long wavelength side as the ratio of AgInS2 to ZnS increased in the solid solutions. The photocatalytic H2 evolution depended on the compositions as well as the photophysical properties. The dependence of the photophysical and photocatalytic properties upon the composition was mainly due to the change in the band position caused by the contribution of the Ag 4d and In 5s5p orbitals to the valence and conduction bands, respectively. It was found from SEM and TEM observations that the solid solutions partially had nanostep structures on their surfaces. The Pt cocatalysts were selectively photodeposited on the edge of the surface nanosteps. It was suggested that the specific surface nanostructure was effective for the suppression of recombination between photogenerated electrons and holes and for the separation of H2 evolution sites from oxidation reaction sites.
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