Quantum Effects on Hydrogen Isotopes Adsorption in Nanopores

We have investigated the applicability of simulations and theoretical techniques for exploring the selectivities of hydrogen isotopes. We have simulated the adsorption isotherms of H₂ in an idealized carbon slit pore at 77 K by using the grand canonical Monte Carlo simulations with the Feynman-Hibbs effective potential (FH-GCMC) and the rigorous path integral method (PI-GCMC), and we obtained good agreement between the isotherms from both simulations. This suggests that FH-GCMC, which uses the approximative Feynman-Hibbs treatment, is as useful as PI-GCMC for exploring H₂ adsorption at 77 K. Moreover, we show that the ideal adsorption solution theory (IAST) can predict the selectivity of D₂ over H₂ in the interstices of single-wall carbon nanotube (SWNT) bundles at 77 K (below 0.1 MPa) very well by comparing the obtained results with the mixture adsorption FH-GCMC simulations. This indicates that IAST is also applicable to the estimation of the selectivity of D₂ over H₂ at moderate pressures and at 77 K from experimental single-component adsorption isotherms. We also demonstrate that the FH-GCMC simulation can reproduce the experimental adsorption isotherms of H₂ and D₂ in aluminophosphate AlPO₄-5 at 77 K. Finally, we analyze the selectivity of D₂ over H₂ by IAST with the experimental single-component adsorption isotherms of H₂ and D₂ at 77 K for a variety of adsorbents: AlPO₄-5, activated carbon fibers (ACFs), HiPco SWNT, and SWNHs. The selectivities predicted by the experimental adsorption data based on the results from the FH-GCMC simulations are presented and discussed.     

Measurement of mean free paths for inelastic electron scattering of Si and SiO2

The effects of accelerating voltage and collection angle on the mean free path for all inelastic electron scattering (lambdap), which is an important parameter for determining specimen thickness by using electron energy-loss spectroscopy, were investigated with crystalline Si and amorphous SiO2. First, thickness of Si film was measured with the convergent-beam electron diffraction method, while thickness of SiO2 particles was estimated from their spherical shape. Then from electron energy-loss spectra, lambdap was evaluated for Si film and SiO2 particles by changing the accelerating voltage (100 to approximately 300 kV) and the collection angle for the scattered electrons. Under the condition of no objective aperture, lambdap for Si film and SiO2 particles was found to increase with the increase of accelerating voltage and to take values of 180+/-6 nm (Si) and 247+/-8 nm (SiO2) at 300 kV. Also, it was found that lambdap in both cases decreases drastically with the increase of collection angle in the range smaller than 25 mrad, while it tends to take a constant value at the collection angle larger than 25 mrad at 200 kV.     

Determining surface orientations of transparent objects based on polarization degrees in visible and infrared wavelengths

Techniques for modeling an object through observation are very important in object recognition and virtual reality. A wide variety of techniques have been developed for modeling objects with opaque surfaces, whereas less attention has been paid to objects with transparent surfaces. A transparent surface has only surface reflection; it has little body reflection. We present a new method for obtaining surface orientations of transparent surfaces through analysis of the degree of polarization in surface reflection and emission in visible and far-infrared wavelengths, respectively. This parameter, the polarization degree of reflected light at the visible wavelengths, is used for determining the surface orientation at a surface point. The polarization degree at visible wavelengths provides two possible solutions, and the proposed method uses the polarization degree at far-infrared wavelengths to resolve this ambiguity.     

Molecular recognition by wall-assembling-type nanocavity in aqueous media

Steroid cyclophanes, each having a macrocyclic ring attached to four bile acid moieties via chiral lysine connectors, were synthesized, and the binding of the 2-naphthylphenylketone (guest) to the steroid cyclophanes in water was investigated. The circular dichroism spectra of the steroid cyclophane with cholic acid and L-lysine were significantly affected by the binding of the guest, and the induced circular dichroism based on the absorption of the achiral guest was also observed. The binding of the guest to the steroid cyclophane with cholic acids and D-lysines induced changes in the circular dichroism spectra with the opposite sign of the molecular ellipticities. An induced circular dichroism spectral change was not observed upon binding of the guest to the analogous host without OH sites. These results strongly suggest that the guest is conformationally fixed through hydrogen bonding between the carbonyl group of the guest and the steroidal hydroxyl group of the host. The assembly of only four steroid residues on the macrocyclic ring probably provided a hydrophobic nanocavity for hydrogen bonding.     

Training of a leaning agent for navigation--inspired by brain-machine interface.

The design clue for the remote control of a mobile robot is inspired by the Talwar's brain-machine interface technology for remotely training and controlling rats. Our biologically inspired autonomous robot control consciousness-based architecture (CBA) is used for the remote control of a robot as a substitute for a rat. CBA is a developmental hierarchy model of the relationship between consciousness and behavior, including a training algorithm. This training algorithm computes a shortcut path to a goal using a cognitive map created based on behavior obstructions during a single successful trial. However, failures in reaching the goal due to errors of the vision and dead reckoning sensors require human intervention to improve autonomous navigation. A human operator remotely intervenes in autonomous behaviors in two ways: low-level intervention in reflexive actions and high-level ones in the cognitive map. Experiments are conducted to test CBA functions for intervention with a joystick for a Khepera robot navigating from the center of a square obstacle with an open side toward a goal. Their statistical results show that both human interventions, especially high-level ones, are effective in drastically improving the success rate of autonomous detours.     

Development of a novel emitting vinyl polymer and its application in organic electroluminescent devices

Abstract— A novel emitting vinyl polymer, poly[4‐(7‐{4‐[N,N‐bis(9,9‐dimethylfluoren‐2‐yl)amino]phenyl}‐2,1,3‐benzothiadiazol‐4‐yl)phenylethylene] (PVFABT), was designed and synthesized. The new vinyl polymer was found to form smooth amorphous films with a high glass‐transition temperature of 199°C. The polymer possesses bipolar character with both electron‐donating and accepting properties. It undergoes reversible anodic oxidation and cathodic reduction to give stable cation and anion radicals. It exhibits intense orange fluorescence in solution and as film. A multilayer organic electroluminescent device using PVFABT as an emitting material emitted orange light, exhibiting high performance.     

Behavior of Buried Flexible Pipe under High Fills and Design Implications

The existing design guidelines for buried flexible pipes are limited to depth up to 10?m. The increasing use of difficult terrains for infrastructure, landfills, and residential and industrial developments has prompted installation of drainage pipelines under 20–30?m high fills. This paper presents the behavior of an instrumented flexible pipe buried under a 47.1?m deep fill. For filling above 20?m, the measured vertical stress above the pipe exhibited a concave distribution, corresponding to 90 and 110% of the average vertical pressure at the center and edges of the pipe, respectively. The measured results suggest that a triangular lateral pressure distribution can lead to overly conservative and uneconomical results for high fills while Spangler’s analysis is unconservative. Based on the measured results, a revised vertical and lateral earth pressure diagram was proposed for the design of flexible pipe under high fills >20?m. This paper proposes closed-form analyses for estimating the moments and displacements of the pipe subjected to high fill earth pressures. These closed-form solutions agree well with the measured pipe displacements and strains.     

Immediate-type heat urticaria: report of a case and study of plasma histamine release

We report a 68-year-old man who had immediate-type heat urticaria with systemic symptoms. Immersing his hand in water at 42 degrees C (heat challenge test) produced an urticarial response, with an increase in the plasma histamine level from 0.26 to 7.64 ng/mL. Administration of oral antihistamines alone did not suppress either the urticarial response or the increase in plasma histamine. However, a combination of antihistamines and desensitization improved the skin lesions and reduced the plasma histamine level. The heat challenge test subsequently provoked a negative response and there was no increase in plasma histamine level 3 months after starting the combination therapy. These results indicate that the histamine level reflected the result of the heat challenge test and the amelioration of the skin eruption.