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The Cement–Opalinus Clay Interaction (CI) Experiment at the Mont Terri rock laboratory is a long-term passive diffusion–reaction experiment between contrasting materials of relevance to engineered barrier systems/near-field for deep disposal of radioactive waste in claystone (Opalinus Clay). Reaction zones at interfaces of Opalinus Clay with two different types of concrete (OPC and “low-pH”/ESDRED) were examined by sampling after 2.2 and 4.9 years. Analytical methods included element mapping (SEM, EPMA), select spot analysis (EDAX), 14C-MMA impregnation for radiography, and powder methods (IR, XRD, clay-exchanger characterisation) on carefully extracted miniature samples (mm). The presence of aggregate grains in concrete made the application of all methods difficult. Common features are a very limited extent of reaction within claystone, and a distinct and regularly zoned reaction zone within the cement matrix that is more extensive in the low-alkali cement (ESDRED). Both interfaces feature a de-calcification zone and overprinted a carbonate alteration zone thought to be mainly responsible for the observed porosity reduction. While OPC shows a distinct sulphate enrichment zone (indicative of ingress from Opalinus Clay), ESDRED displays a wide Mg-enriched zone, also with claystone pore-water as a source. A conclusion is that substitution of OPC by low-alkali cementitious products is not advantageous or necessary solely for the purpose of minimizing the extent of reaction between claystone and cementitious materials. Implications for reactive transport modelling are discussed.

We report a vertically stacked graphene tunnel junction with an atomically thin insulating layer for novel function devices. The insulating water layer sandwiched between graphene samples as a tunnel barrier which is fabricated through deionized (DI) water treatment of epitaxial graphene. Two graphene samples fabricated by SiC thermal decomposition are directly bonded to each other in a face-to-face manner. Vertically stacked graphene samples without DI water treated formed an ohmic junction. By inserting the structured water layer as tunnel barrier, the stacked junction exhibits Direct tunneling (DT) characteristics in a low-electric-field regime and Fowler-Nordheim tunneling (FNT) characteristics in a high-electric-field regime. The thickness of the structured water layer is estimated to be 0.28 nm by fitting the FNT formula. The very thin structured water layer is stable as tunnel barrier on epitaxial graphene for diode devices, which will have a widely application in electronic devices.

The laboratory experiment was done that 1.0mol/L sodium hydroxide solution was injected to the compacted bentonite whose density is the same as the prospected value in the concept of the intermediate-level disposal in Japan in the circumstance of 70°C temperature. After the injection of the alkali solution for approximately 600 days, the bentonite was taken out of the apparatus and some sorts of analysis were done. The accompanying minerals in the bentonite, calcedony and quartz, were dissolved and disappeared in XRD charts. Then analcime was precipitated as a secondary mineral. Although montmorillonite was dissolved, the mass fraction of it was kept approximately. The hydraulic conductivity of the bentonite calculated using the flow rate at the end of the injection of alkali solution was smaller than the prospected value based on a widely-used empirical model of the hydraulic conductivity of compacted bentonite as a function of the equivalent concentration of pore solution, montmorillonite partial void ratio, and the ratio of sodium ion equivalent to the exchangeable cation equivalent. The reasons for the difference were supposed to be the decrease of pore size brought by mineral dissolution and the large viscosity of pore solution involving high concentration aqueous silicon.

Cyanidin 3-O-beta-D-glucoside (CG) was purified from black bean seed coat and other anthocyanins were prepared from red grape skin. These anthocyanins were identified by Mass, and 1H- and 13C-NMR. The effects of four anthocyanins on cell viability in human leukemia Molt 4B cells were investigated. The anthocyanins displayed strong growth inhibitory effects against human leukemia Molt 4B cells. Morphological changes showing apoptotic bodies were observed in the Molt 4B cells treated with these anthocyanins. The fragmentations by these anthocyanins of DNA to oligonucleosomal-sized fragments, that is a characteristic of apoptosis, were observed to be concentration-dependent. N-acetyl-L-cysteine, an antioxidant, suppressed the fragmentation of DNA by these anthocyanins. These findings suggest that growth inhibition of Molt 4B cells by these anthocyanins result from the induction of apoptosis by these compounds and that active oxygen is involved in the induction of apoptosis in the Molt 4B cells.

Cyanidin 3-O-beta-D-glucoside (CG) was purified from black bean seed coat and other anthocyanins were prepared from red grape skin. These anthocyanins were identified by Mass, and 1H- and 13C-NMR. The effects of four anthocyanins on cell viability in human leukemia Molt 4B cells were investigated. The anthocyanins displayed strong growth inhibitory effects against human leukemia Molt 4B cells. Morphological changes showing apoptotic bodies were observed in the Molt 4B cells treated with these anthocyanins. The fragmentations by these anthocyanins of DNA to oligonucleosomal-sized fragments, that is a characteristic of apoptosis, were observed to be concentration-dependent. N-acetyl-L-cysteine, an antioxidant, suppressed the fragmentation of DNA by these anthocyanins. These findings suggest that growth inhibition of Molt 4B cells by these anthocyanins result from the induction of apoptosis by these compounds and that active oxygen is involved in the induction of apoptosis in the Molt 4B cells.

Aftershocks can increase the damage and possibility of structural collapse soon after a major earthquake. When it is considered whether the structure should be repaired or not after a major earthquake, it is necessary to estimate the influence of aftershocks on mainshock-damaged structure and the likelihood for occurrence of aftershocks shortly after the main shock. In the present study, the damage evaluations of simplified SSI system with the influence of aftershocks are examined. Besides, methodologies for evaluating the collapse probability of mainshock-damaged structure shortly after the main shock by considering the likelihood for occurrence of aftershocks are proposed. It is shown that the proposed estimation method can effectively evaluate the collapse probability of structure due to aftershocks.