11 research outputs found
Impurity Substitution Effect on Magnetoelectric Properties of CaBaCo4O7 Crystals
AbstractWe have investigated effects of impurity substitution of Fe for Co sites on magnetic and dielectric properties in CaBa(Co1-xFex)4O7 crystals in magnetic fields. The non-doped compound, CaBaCo4O7 with the polar space group Pbn21, shows a large change of electric polarization ΔP along the c axis below a ferrimagnetic transition temperature. With increasing x, the transition temperatures for the ferrimagnetic and ferroelectric-like phases are shifted towards lower and these phases are completely collapsed above x=1.56%. We have also investigated the magnetic field effects for CaBa(Co1-xFex)4O7 crystal with a doping level x=0.5% where the ferrimagnetic and ferroelectric-like phases sustain. Then a relatively large magnetocapacitance, Δɛ(H)/ɛ(0) [ɛ(H) – ɛ(0)]/ɛ(0), of 45% at 58K was observed, which is not significantly reduced from the parent compound
Syntheses and Characterization of New Nickel Coordination Polymers with 4,4′-Dipyridylsulfide. Dynamic Rearrangements of One-Dimensional Chains Responding to External Stimuli: Temperature Variation and Guest Releases/Re-Inclusions
Crystal structures and dynamic rearrangements of one-dimensional coordination
polymers with 4,4′-dipyridylsulfide (dps) have been studied.
Reaction of Ni(NO3)2·6H2O with dps
in EtOH yielded
[Ni(dps)2(NO3)2]
·EtOH (1), which had channels filled with guest EtOH
molecules among the four Ni(dps)2 chains. This coordination polymer
reversibly transformed the channel structure responding to temperature
variations. Immersion of 1 in m-xylene released
guest EtOH molecules to yield a guest-free coordination polymer
[Ni(dps)2(NO3)2]
(2a), which was also obtained by treatment of
Ni(NO3)2·6H2O with dps in MeOH.
On the other hand, removal of the guest molecules from 1 upon
heating at 130 °C under reduced pressure produced a guest-free
coordination polymer
[Ni(dps)2(NO3)2]
(2b). Although the 2a and 2b
guest-free coordination polymers have the same formula, they showed differences
in the assembled structures of the one-dimensional chains. Exposure of
2b to EtOH vapor reproduced 1, while
2a did not convert to 1 in a similar reaction.
Reaction of Ni(NO3)2·6H2O with dps
in acetone provided
[Ni(dps)(NO3)2(H2O)]
·Me2CO (4) with no channel structure.
When MeOH or acetone was used as a reaction solvent, the
[Ni(dps)2(NO3)2]
· (guest molecule) type coordination polymer, which was observed in
1, was not formed. Nevertheless, the reaction of
Ni(NO3)2·6H2O with dps in
MeOH/acetone mixed solution produced
[Ni(dps)2(NO3)2]·0.5(MeOH·acetone)
(5), which has an isostructural Ni-dps framework to
1
Hourly Sampling of PM_<2.5> at an AERONET site in Higashi-Osaka, Japan : Dust Events During Spring 2006
To monitor urban atmospheric particles, we have undertaken simultaneous measurements of aerosols and suspended particulate matter (SPM) at Kinki University Campus, Higashi–Osaka, Japan, since 2004. The largest dust event recorded during our long-term observations was detected during the spring of 2006. We also examined the relationship between PM_ concentrations and aerosol properties obtained from radiometry using a multi-spectral photometer located at a NASA/AERONET station. We found a linear correlation between aerosol optical thickness and PM_ concentrations for both ordinary days and days with dust events. This fact indicates that aerosol characteristics can be estimated from SPM data, and vice versa. Combining radiometric aerosol information with surface-level particulate mass measurements is useful in studying air quality and aerosol properties.本文データは一部CiNiiから複製したものである
Participation of Somatic Stem Cells, Labeled by a Unique Antibody (A3) Recognizing Both N-glycan and Peptide, to Hair Follicle Cycle and Cutaneous Wound Healing in Rats
A monoclonal antibody (A3) was generated by using rat malignant fibrous histiocytoma (MFH) cells as the antigen. Generally, MFH is considered to be a sarcoma derived from undifferentiated mesenchymal cells. Molecular biological analyses using the lysate of rat MFH cells revealed that A3 is a conformation specific antibody recognizing both N-glycan and peptide. A3-labeled cells in bone marrow were regarded as somatic stem cells, because the cells partly coexpressed CD90 and CD105 (both immature mesenchymal markers). In the hair follicle cycle, particularly the anagen, the immature epithelial cells (suprabasal cells) near the bulge and some immature mesenchymal cells in the disassembling dermal papilla and regenerating connective tissue sheath/hair papilla reacted to A3. In the cutaneous wound-healing process, A3-labeled epithelial cells participated in re-epithelialization in the wound bed, and apparently, the labeled cells were derived from the hair bulge; in addition, A3-labeled immature mesenchymal cells in the connective tissue sheath of hair follicles at the wound edge showed the expansion of the A3 immunolabeling. A3-labeled immature epithelial and mesenchymal cells contributed to morphogenesis in the hair cycle and tissue repair after a cutaneous wound. A3 could become a unique antibody to identify somatic stem cells capable of differentiating both epithelial and mesenchymal cells in rat tissues