Recently, lithium-ion batteries have been attracting more interest for use in automotive applications. Lithium resources are confi rmed to be unevenly distributed in South America, and the cost of the lithium raw materials has roughly doubled from the fi rst practical application in 1991 to the present and is increasing due to global demand for lithium-ion accumulators. Since the electrochemical equivalent and standard potential of sodium are the most advantageous after lithium, sodium based energy storage is of great interest to realize lithium-free high energy and high voltage batteries. However, to the best of our knowledge, there have been no successful reports on electrochemical sodium insertion materials for battery applications; the major challenge is the negative electrode and its passivation. In this study, we achieve high capacity and excellent reversibility sodium-insertion performance of hard-carbon and layered NaNi 0.5 Mn 0.5 O 2 electrodes in propylene carbonate electrolyte solutions. The structural change and passivation for hard-carbon are investigated to study the reversible sodium insertion. The 3-volt secondary Na-ion battery possessing environmental and cost friendliness, Na + -shuttlecock hard-carbon/NaNi 0.5 Mn 0.5 O 2 cell, demonstrates steady cycling performance as next generation secondary batteries and an alternative to Li-ion batteries.

TiO 2 loaded with Pd particles (Pd/TiO 2 ), when photoirradiated at λ > 300 nm in alcohol containing primary amine, efficiently promotes N-monoalkylation of amine with alcohol, producing the corresponding secondary amine with almost quantitative yields. This occurs via tandem photocatalytic and catalytic reactions: (i) Pd-assisted alcohol oxidation on the photoactivated TiO 2 , (ii) condensation of the formed aldehyde with amine on the TiO 2 surface, and (iii) hydrogenation of the formed imine by the surface H atoms on the Pd particles. The rate-determining step is the imine hydrogenation, and the reaction depends strongly on the size of the Pd particles. The catalyst with 0.3 wt % Pd, containing 2−2.5 nm Pd particles, shows the highest activity for imine hydrogenation, and smaller or larger Pd particles are inefficient. Calculations of the number of surface Pd atoms based on the cuboctahedron particle model revealed that the Pd atoms on the triangle site of Pd particles are the active site for hydrogenation. Larger Pd particles contain a larger number of these Pd atoms and are effective for imine hydrogenation. Alcohols, however, are strongly adsorbed onto the larger triangle site and suppress imine hydrogenation. As a result of this, the catalyst with 2−2.5 nm Pd particles, which contains a relatively larger number of Pd atoms on the triangle site and does not promote strong alcohol adsorption, shows the highest activity for imine hydrogenation and promotes efficient N-monoalkylation of amine with alcohol under photoirradiation.

Antibody binding to bovine serum albumin (BSA) and human serum albumin (HSA) immobilized onto gold nanoparticles was studied by means of localized surface plasmon resonance (LSPR) spectroscopy. Amine-modified glass was prepared by self-assembly of amine-terminated silane on substrate, and gold (Au) nanoparticles were deposited on the amine-modified glass substrate. Au nanoparticles deposited on the glass surface were functionalized by BSA and HSA. BSA immobilization was confirmed by LSPR spectroscopy in conjunction with surface-enhanced Raman scattering spectroscopy. Then, LSPR response attributable to the binding of anti-BSA and anti-HSA to BSA- and HSA-functionalized Au nanoparticles, respectively, was examined. Anti-HSA at levels larger than approximately 10 nM could be detected by HSA-immobilized chips with LSPR optical response, which was saturated at concentrations greater than approximately 650 nM of anti-HSA.

Predicting RNA secondary structure is often the first step to determining the structure of RNA. Prediction approaches have historically avoided searching for pseudoknots because of the extreme combinatorial and time complexity of the problem. Yet neglecting pseudoknots limits the utility of such approaches. Here, an algorithm utilizing structure mapping and thermodynamics is introduced for RNA pseudoknot prediction that finds the minimum free energy and identifies information about the flexibility of the RNA. The heuristic approach takes advantage of the 5′ to 3′ folding direction of many biological RNA molecules and is consistent with the hierarchical folding hypothesis and the contact order model. Mapping methods are used to build and analyze the folded structure for pseudoknots and to add important 3D structural considerations. The program can predict some well known pseudoknot structures correctly. The results of this study suggest that many functional RNA sequences are optimized for proper folding. They also suggest directions we can proceed in the future to achieve even better results.

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