The rotational spectrum of the carbon dioxide–propylene oxide (CO2–PO) complex was measured in the frequency region from 5 up to 24GHz by Fourier transform microwave spectroscopy. For the normal species 82 a-type, 53 b-type, and 43 c-type transitions were observed, while a-type and b-type transitions were assigned for the four isotopic species with one 13C in each of the PO or CO2 moiety in natural abundance. Enriched C18OO and C18O2 samples were employed to record a-type, b-type, and c-type transitions for the complexes with the respective isotopic CO2 species bound to PO, including the two different C18OO–PO complexes: the inner OC18O–PO and the outer 18OCO–PO. All the observed transition frequencies were analyzed for the normal and the three 18O–carbon dioxide complexes using a one CH3 group internal rotation and overall rotation Hamiltonian. The potential barrier height V3 to internal rotation of the CH3 in the PO was determined to be 859.8 (62) cm−1. The rotational constants derived for the CO2–PO complex led to the structure in which the CO2 moiety was located in one side of the PO ether plane opposite to that of the CH3 group, namely an anti-conformer. The intermolecular bonding of the CO2–PO was found weaker than those of the CO2–EO and the CO2–DME; by assuming a Lennard–Jones-type potential, the force constant of the van der Waals stretching mode and the dissociation energy were estimated to be 5.0Nm−1 and 5.7kJmol−1, respectively, which were to be compared with those of the CO2–EO and the CO2–DME: 8.0Nm−1 and 7.1kJmol−1 and 10.9Nm−1 and 9.7kJmol−1, respectively. It is interesting to note that the intensities of the inner OC18O–PO spectra are stronger than those of the outer 18OCO–PO ones. This observation was explained by the zero-point energy of the inner conformer being a little smaller than that of the outer.
Aqueous alteration was one of the earliest geological processes in the solar system and significantly shaped the mineralogical diversity observed in primitive minor bodies. Carbonate minerals are reliable tracers of the physicochemical conditions during alteration processes on early planetesimals. We present a comprehensive characterization of carbonates in the returned samples of asteroids Ryugu and Bennu, performed using the MicrOmega near-infrared hyperspectral microscope. We identify two major carbonate species, dolomite (CaMg(CO3)2) and breunnerite ((Mg,Fe)CO3), with similar relative abundances and mean elemental compositions on both asteroids, indicating analogous aqueous alteration pathways on their parent bodies. A general spatial separation of dolomite and breunnerite is observed, indicating that at size scales of 10-100 mu m, alteration conditions favored the precipitation of one species over the other. We interpret this as evidence for a spatially heterogeneous local water-rock ratio, suggesting that a high local water-rock ratio suppresses the formation of dolomite, instead favoring precipitation of breunnerites. Based on relative carbonate abundances, we conclude that chambers A (sampling the surface) and C (predominantly sampling the subsurface) of the Ryugu sample contain different mixtures of lithologies with different alteration degrees.
In this paper, we propose a natural voice dialogue system based on a voice dialogue system using generative AI (ChatGPT) which can communicate with users, including nonverbal behavior similar to that of humans, according to the user's seating position and facial expression. In this paper, we developed a prototype of the proposed system and evaluated it. The results of a questionnaire survey conducted during a demonstration confirmed the effectiveness of the proposed system.
In the era of Society 5.0, where cyberspace and physical space are increasingly integrated, securing IoT actuators in mobile robots and autonomous vehicles has become critical. As malware becomes stealthier and AI-driven, conventional detection methods are often inadequate. This study proposes a Zero Trust IoT Security Framework (ZeTiots FW) for mobile robot platforms, focusing on TurtleBot3 as a representative case. The framework integrates zero trust principles with physical-layer safety using infrared sensors to proactively prevent real-world harm.
This study proposes a three-terminal self-biased channel diode (SBCD) with a Fin-based split-gate (SG) structure as a low-loss, low-cost alternative to Schottky barrier diodes in power supplies and solar cells. The proposed SBCD prevents thermal runaway and addresses trade-offs between on-voltage, breakdown voltage, and reverse recovery loss. To enhance switching performance, a vertical Fin structure with an SG electrode was introduced to increase gate capacitance. Device simulations were conducted with various SG heights (0.6–1.4 μm) and unit sizes (5–15 μm). The device’s characteristics varied depending on the SG connection: anode shorted, floating, or grounded. Notably, when the SG was shorted to the anode, reverse recovery time (trr) and charge (Qrr) improved by 77
