In order to study influence of automobile traffic on a local urban atmospheric environment, we have investigated suspended particulate matter (SPM) collected at sampling sites in a region which includes a major highwa...
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In order to study influence of automobile traffic on a local urban atmospheric environment, we have investigated suspended particulate matter (SPM) collected at sampling sites in a region which includes a major highway and a residential area in the southern part of Tokyo during August - November 1999. The atomic composition of each sample was measured by means of PIXE analysis using a 2.0 MeV proton beam. Sixteen elements were quantitatively measured. The positional dependence of SPM loading was determined for each element using samples simultaneously collected at three different sites. For the experimental results obtained fordownwind conditions, the measured concentration as a function of the distance from the highway was compared with a simple calculation based on the Gaussian plume model. The concentration distribution of some heavy elements in the fine fraction is well reproduced by this analysis. It has been found that for ordinary moderate downwind conditions the area within 300-400 m from the highway is directly affected by emission due to the automobile traffic.
The electronic and crystal structures of YbCuxGa2−x under pressure were investigated by high-resolution x-ray absorption spectroscopy (XAS) at the Yb-L3 absorption edge and x-ray diffraction. A rapid valence transitio...
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The electronic and crystal structures of YbCuxGa2−x under pressure were investigated by high-resolution x-ray absorption spectroscopy (XAS) at the Yb-L3 absorption edge and x-ray diffraction. A rapid valence transition was found in YbCu0.5Ga1.5 around 5 GPa accompanying the structural phase transition. In YbCuGa and YbCu1.5Ga0.5 the Yb valence increased gradually up to 5–7 GPa and 16 GPa with pressure, respectively, anddid not show a significant change above those pressures. XAS study at the Cu-L absorption edge was also performed. The major hybridization partner of Yb 4f electrons switched from Ga to Cu with increasing the Cu content around x=1–1.5, where the c–f hybridization was weakest. Photoelectron spectroscopy was performed around Yb 4d–4f resonance energy and at 8.4 eV.
Fiber-based material systems are emerging as key elements for next-generation wearable devices due to theirremarkable advantages,including large mechanical deformability,breathability,and high ***,greatly improved me...
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Fiber-based material systems are emerging as key elements for next-generation wearable devices due to theirremarkable advantages,including large mechanical deformability,breathability,and high ***,greatly improved mechani-cal stability has been established in functional fiber systems by introducing atomic-thick two-dimensional(2d)*** development of intelligent fibers that can respond to various external stimuli is strongly needed for versatile *** this work,helical-shaped semiconductive fibers capable of multifunctional sensing are obtained by wet-spinning MoS_(2) liquid crystal(LC)*** mechanical properties of the MoS_(2) fibers were improved by exploiting high-purity LC dispersions consisting of uniformly-sized MoS_(2) ***,three-dimensional(3d)helical fibers with structural chirality were successfully constructed by controlling the wet-spinning process *** helical fibers exhibited multifunctional sensing characteristics,including(1)photodetection,(2)pH monitoring,(3)gas detection,and(4)3d strain sensing.2d materials with semiconducting properties as well as abundant surface reactive sites enable smart multifunctionalities in one-dimensional(1d)and helical fiber geometry,which is potentially useful fordiverse applications such as wearable internet of things(IoT)devices and soft robotics.
Controlling the dynamics of ionic liquids (ILs) is a significant issue for widespread use. Metal–organic frameworks (MOFs) are ideal host materials for ILs because of their small micropores and tunable host–guest in...
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Controlling the dynamics of ionic liquids (ILs) is a significant issue for widespread use. Metal–organic frameworks (MOFs) are ideal host materials for ILs because of their small micropores and tunable host–guest interactions. Herein, we demonstrate the first example of an IL incorporated within the micropores of a MOF. The system studied consisted of EMI‐TFSA (1‐ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)amide) and ZIF‐8 (composed of Zn(MeIM) 2 ; H(MeIM)=2‐methylimidazole) as the IL and MOF, respectively. Construction of the EMI‐TFSA in ZIF‐8 was confirmed by X‐ray powderdiffraction, nitrogen gas adsorption, and infrared absorption spectroscopy. differential scanning calorimetry and solid‐state NMr measurements showed that the EMI‐TFSA inside the micropores demonstrated no freezing transition down to 123 K, whereas bulk EMI‐TFSA froze at 231 K. Such anomalous phase behavior originates from the nanosize effect of the MOF on the IL. This result provides a novel strategy for stabilizing the liquid phase of the ILs down to a lower temperature region.
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