Recently, many and various microbial products appear on the market. However, almost all of them could not have sufficient effects. The expectation of users to microbial products is rising up. It is because of the directions for the environmental friendly and sustainable industrial activity. In addition, it is expected that the development of genetic engineering can make the possibility for the practical use of potential ability of microbes which is still not known.
There are two major problems in practical use of microbial products. First, the transplanting of microbes into the target environment is not easy. Because, many indigenous microbes are inhabit in the industrial field and they doesn't allow introduced microbe(s) to be dominant in the field. Moreover, the environment of target fields is very fickle for introduced microbes. Second, the insufficient information of products promotes the misunderstanding to the users for the effect of the products.
To the practical use of microbial products in the industrial fields, the researches and developments of reliable and effective products are required. Thereby, the preparations of special feeding and habitat are important for introduced microbes. Moreover, the analyses of microbes transplanted in the industrial fields are important to guarantee both the quality of the products and the correct information to users.
The purpose of this communication is the clarification of present challenge for the practical use of microbial products in the industrial fields. Then, this communication suggests the several ways for the research and development of reliable microbial products and useful analytical methods for microbial community by genetic engineering.

抄録全体を表示

Size effect and time dependency are observed in most rock or bedrock. A lot of researches have been performed on both of them up to now. However, many points have been left unsettled although they are considered to be important especially for long-term stability of a large structure.
In this study, long-term slope stability around the Three Gorges reservoir was discussed considering both size effect and time dependency. There are still not so many researches in the size effect related to slope stability, and it is difficult to presume the relationships between the size effect and slope stability theoretically or experimentally. So, in this study the size effect was estimated by data analysis of apparent friction and nominal dimension of landslides occurred in the past.
Time dependency concerning slope collapse or landslide is well known. If the time dependency is remarkable, just a relatively low stress can lead to gradual deformation and then final failure. For evaluating the stability of, for example, 100 years, it is necessary to understand time dependency of the rock. For this reason, the rock collected in situ was tested in laboratory to obtain the time dependency by the recently developed testing method with relatively small specimens.
Overdesign factor required for long-term slope stability was calculated based on the size effect and the time dependency. The long-term slope stability around the Three Gorges reservoir was discussed based on the estimated overdesign factor.

抄録全体を表示

Potentiostatic electrodeposition behavior of dendritic copper from acidic copper(I) chloride (cuprous chloride) bath containing sodium chloride and sodium bromide was investigated. Deposition current density of the dendrite onto a titanium cathode was lower than that onto a copper cathode with the same surface area, while the current efficiency and the morphology, or appearance, of copper dendrite were independent of the cathode material. The reproducibility of the current for the dendrite was poorer when as-polished titanium cathode was used, although a surface treatment of the cathode with an HF-H₃PO₄ solution before electrodeposition improved the reproducibility. The content of sodium as an impurity in the dendrite was independent of the cathode material.

抄録全体を表示

For flood prevention, power generation and conveyance, the world's largest Three Gorges Dam was begun to construct in 1993. However, the problem of landslide around the Three Gorges reservoir has not been solved completely so far. Although a lot of geological investigations have been carried out in the field, the role of rock mechanical characteristics in the failure of rock slope has not been cleared thoroughly.
In order to study the geological setting and the mechanical characteristic of the landslide area around the Three Gorges reservoir, field investigation and laboratory work including microscope observation, X-ray powder diffraction analysis and uniaxial compressive tests have been carried out. Rock specimens such as two muddy sandstones, a red mudstone, a limestone and a sandstone were collected and examined.
The main mineral composition of examined rock specimens except for limestone is quartz. Under the air-dried condition, sandstone is the strongest and weathered muddy sandstone is the weakest. It is interesting to note that calcium contents (carbonate observed) in unweathered muddy sandstone are significantly decreased in weathered one. The decrease in strength for the weathered rock may arise from the dissolution of calcium. For all sample rocks, uniaxial compressive strength shows remarkable decrease under the water-saturated condition. It may be attributed to high content of clay minerals.
Complete stress-strain curves were obtained. For all sample rocks, stress increased almost linearly with strain up to the peak strength and then dropped rapidly indicating brittle feature. Weakening under water-saturated condition and high degree of brittleness indicate that very careful and sophisticated measure is necessary to prevent landslide in the area.

抄録全体を表示