Partially unzipped carbon nanotubes as a superior catalyst support for PEM fuel cells

Partially unzipped carbon nanotubes prepared by strong oxidation and thermal expansion of carbon nanotubes were explored as an advanced catalyst support for PEM fuel cells. The unique hybrid structure of 1D nanotube and 2D double-side graphene resulted in an outstanding electrocatalytic performance.     

A nonlinear signal-based control method and its applications to input identification for nonlinear SIMO problems

The problem of control system design can be conceptualised as identifying an input signal to a plant (the system to be controlled) so that the corresponding output matches that of a pre-defined reference signal. Primarily, this problem is solved via well-known techniques based upon the principle of feedback design, an essential component for ensuring stability and robustness of the controlled system. However, feedforward design techniques also have a large part to play, whereby (in the absence of feedback control and assuming that the plant is stable) a model of the plant dynamics can be used to modify the reference signal so that the resultant feedforward input signal generates a plant output signal that is sufficiently close to the original reference signal.     

Ion Selectivity of Water Molecules in Subnanoporous Liquid-Crystalline Water-Treatment Membranes: A Structural Study of Hydrogen Bonding

We demonstrate hydrogen-bonded structures of water in self-organized subnanoporous water treatment membranes obtained using synchrotron-based high-resolution soft X-ray emission spectroscopy. The ion selectivity of these water treatment membranes is usually understood by the size compatibility of nanochannels in the membrane with the Stokes radius of hydrated ions, or by electrostatic interaction between charges inside the nanochannels and such ions. However, based on a comparison between the hydrogen-bonded structures of water molecules in the nanochannels of the water treatment membrane and those surrounding the ions, we propose a definite contribution of structural consistency among the associated hydrogen-bonded water molecules to the ion selectivity. Our observation delivers a novel concept to the design of water treatment membranes where water molecules in the nanochannel can be regarded as a part of the material that controls the ion selectivity.     

On the presence of the S4z-term in Fe(HCOO)2 · 2H2O

The magnetic specific heat of ferrous formate dihydrate is analysed on the basis of a model, $\text{S}{}_{\mathrm{A}}\text{=}\text{1}\text{2}$ and S_B = 2. The experimental result turns out to be well explained by the introduction of a large S⁴_z-term for B site ions.     

Effect of the frustration to the ground state energy and entropy of the spin-glass in the random bond Ising model on the square lattice

The energies and the entropies of the spin-glass state and the paramagnetic state at T = 0 of the random-bond Ising mixture of the ferromagnetic bond (concentration p) and the antiferromagnetic bond (concentration 1 ? p) on the square lattice are calculated by the method of the square approximation in the simple version. A self-consistent relation that the partial trace of the normalized density matrix of the square cluster is equal to that of the vertex ($\text{tr}\text{(}{}_{\mathrm{jkl}}\text{?}\text{?}{}^{\mathrm{(4)}}\text{(i,j,k,l) =}\text{?}\text{?}{}^{\mathrm{(1)}}\text{(i)}$) leads to an integral equation for the distribution function of the effective fields, and it is solved exactly at T = 0. The symmetric solution of the integral equation contains the paramagnetic state and two spin-glass states, SG1 and SG2. The energies and the entropies of these states are obtained as functions of the concentration p. The values of the energies per spin at $\text{p =}\text{1}\text{2}$ are -0.75|E_F|, -0.72746|E_F|, -0.72543|E_F|, and correspond to a minimum, a saddle point, and a maximum, respectively, and the values of the entropies are 0, 0.082886k_B, and 0.054457k_B, respectively. The present results are compared with those of the pair approximation and discussed.     

Homological properties of balanced Cohen-Macaulay algebras

A balanced Cohen-Macaulay algebra is a connected algebra having a balanced dualizing complex in the sense of Yekutieli (1992) for some integer and some graded - bimodule . We study some homological properties of a balanced Cohen-Macaulay algebra. In particular, we will prove the following theorem:
 

As a corollary, we will have the following characterizations of AS Gorenstein algebras and AS regular algebras:
 

     

Participation of the surface structure of Pharaonis phoborhodopsin, ppR and its A149S and A149V mutants, consisting of the C-terminal alpha-helix and E-F loop, in the complex-formation with the cognate transducer pHtrII, as revealed by site-directed 13C solid-state NMR

We have recorded 13C solid state NMR spectra of [3-13C]Ala-labeled pharaonis phoborhodopsin (ppR) and its mutants, A149S and A149V, complexed with the cognate transducer pharaonis halobacterial transducer II protein (pHtrII) (1-159), to gain insight into a possible role of their cytoplasmic surface structure including the C-terminal alpha-helix and E-F loop for stabilization of the 2:2 complex, by both cross-polarization magic angle spinning (CP-MAS) and dipolar decoupled (DD)-MAS NMR techniques. We found that 13C CP-MAS NMR spectra of [3-13C]Ala-ppR, A149S and A149V complexed with the transducer pHtrII are very similar, reflecting their conformation and dynamics changes caused by mutual interactions through the transmembrane alpha-helical surfaces. In contrast, their DD-MAS NMR spectral features are quite different between [3-13C]Ala-A149S and A149V in the complexes with pHtrII: 13C DD-MAS NMR spectrum of [3-13C]Ala-A149S complex is rather similar to that of the uncomplexed form, while the corresponding spectral feature of A149V complex is similar to that of ppR complex in the C-terminal tip region. This is because more flexible surface structure detected by the DD-MAS NMR spectra are more directly influenced by the dynamics changes than the CP-MAS NMR. It turned out, therefore, that an altered surface structure of A149S resulted in destabilized complex as viewed from the 13C NMR spectrum of the surface areas, probably because of modified conformation at the corner of the helix E in addition to the change of hydropathy. It is, therefore, concluded that the surface structure of ppR including the C-terminal alpha-helix and the E-F loops is directly involved in the stabilization of the complex through conformational stability of the helix E.     

Enantioselective total synthesis of heliespirone B

The first enantiocontrolled total synthesis of heliespirone B has been accomplished employing a biomimetic intramolecular oxy-Michael reaction followed by the regio- and diastereoselective reduction of the carbonyl function as key steps.