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Abstract The clathrate hydrate formation at the interface between liquefied carbon dioxide (CO 2 ) and liquid water is one of the key processes in the course of direct CO 2 disposal into deep seas—an option to mitigate the emission of CO 2 into the atmosphere. Eight different models have been proposed so far on the formation and metabolic self-preservation of a hydrate film at the interface and also the mass transfer of CO 2 across the hydrate film. This paper reviews those rival models one by one and illustrates how they are discrepant. Each model is critically examined, and if any, its weakness in physical reality or mathematical formulation is pointed out. The state of the art of hydrate-film modeling thus revealed suggests the necessity of more careful consulting of pertinent experimental observations to establish our physical view about hydrate films, which should serve as the base of any further work on hydrate-film modeling.

Abstract The clathrate hydrate formation at the interface between liquefied carbon dioxide (CO 2 ) and liquid water is one of the key processes in the course of direct CO 2 disposal into deep seas—an option to mitigate the emission of CO 2 into the atmosphere. Eight different models have been proposed so far on the formation and metabolic self-preservation of a hydrate film at the interface and also the mass transfer of CO 2 across the hydrate film. This paper reviews those rival models one by one and illustrates how they are discrepant. Each model is critically examined, and if any, its weakness in physical reality or mathematical formulation is pointed out. The state of the art of hydrate-film modeling thus revealed suggests the necessity of more careful consulting of pertinent experimental observations to establish our physical view about hydrate films, which should serve as the base of any further work on hydrate-film modeling.

AbstractVery high photocurrent densities of up to 80 mA/cm2, observed at H2‐evolving p‐Si electrodes having high electric resistivity under AM1 (100 mW/cm2) illumination, are caused by the electron injection from the back side metal into the conduction band of p‐Si.

AbstractVery high photocurrent densities of up to 80 mA/cm2, observed at H2‐evolving p‐Si electrodes having high electric resistivity under AM1 (100 mW/cm2) illumination, are caused by the electron injection from the back side metal into the conduction band of p‐Si.

Abstract To elucidate the gas generation mechanism due to electrolyte decomposition in commercial lithium-ion cells after long cycling, we developed a device which can accurately determine the volume of generated gas in the cell. Experiments on LixC6/Li1−xCoO2 cells using electrolytes such as 1 M LiPF6 in propylene carbonate (PC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC) are presented and discussed. In the nominal voltage range (4.2–2.5 V), compositional change due mainly to ester exchange reaction occurs, and gaseous products in the cell are little. Generated gas volume and compositional change in the electrolyte are detected largely in overcharged cells, and we discussed that gas generation due to electrolyte decomposition involves different decomposition reactions in overcharged and overdischarged cells.

Abstract To elucidate the gas generation mechanism due to electrolyte decomposition in commercial lithium-ion cells after long cycling, we developed a device which can accurately determine the volume of generated gas in the cell. Experiments on LixC6/Li1−xCoO2 cells using electrolytes such as 1 M LiPF6 in propylene carbonate (PC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC) are presented and discussed. In the nominal voltage range (4.2–2.5 V), compositional change due mainly to ester exchange reaction occurs, and gaseous products in the cell are little. Generated gas volume and compositional change in the electrolyte are detected largely in overcharged cells, and we discussed that gas generation due to electrolyte decomposition involves different decomposition reactions in overcharged and overdischarged cells.

Capture of trace amounts (parts per trillion or ppt level) of 90Sr from highly Na+-rich (5 M or 115 000 parts per million) liquid wastes produced from reprocessing of spent nuclear fuel rods is crucial for continuous operation of nuclear power plants.