The control factors controlling the growth of native silicon oxide on silicon (Si) surfaces have been identified. The coexistence of oxygen and water or moisture is required for growth of native oxide both in air and in ultrapure water at room temperature. Layer-by-layer growth of native oxide films occurs on Si surfaces exposed to air. Growth of native oxides on n-Si in ultrapure water is described by a parabolic law, while the native oxide film thickness on n+-Si in ultrapure water saturates at 10 Å. The native oxide growth on n-Si in ultrapure water is continuously accompanied by a dissolution of Si into the water and degrades the atomic flatness at the oxide-Si interface, producing a rough oxide surface. A dissolution of Si into the water has not been observed for the Si wafer having surface covered by the native oxide grown in air. Native oxides grown in air and in ultrapure de-ionized water have been demonstrated experimentally to exhibit remarkable differences such as contact angles of ultrapure water drops and chemical binding energy. These chemical bond structures for native oxide films grown in air and in ultrapure water are also discussed.

Native silicon (Si) oxide growth on Si (100) wafers in air and in ultrapure water at room temperature requires coexistence of water and oxygen in the air and ultrapure water ambients. The growth rate data on n-, n+-, and p+-Si (100) in air indicate layer-by-layer growth of an oxide. The growth rate on n-Si (100) in ultrapure water may be governed by a parabolic law. For native oxide growth in ultrapure water, the number of Si atoms dissolved in ultrapure water is over one order of magnitude larger than the number of Si atoms contained in the grown native oxide film. The structural difference between the native oxide film in air and in ultrapure water is also discussed.

In order to discuss the reactivity of carbonaceous materials with CO 2 , the Raman spectroscopy analysis was carried out. Nine kinds of materials were examined. The Raman spectra of ordered materials could be assigned to the graphite structure and its defect, but those of disordered materials could not. New parameters were derived to evaluate the structure of the latter. Using the parameters, the structure change was followed during high temperature heat treatment. The disordered material consists of random structure, graphite structure and its defects. The random structure changes to the graphite structure with many defects and the defects decrease with the heat treatment temperature. The reaction rate constant is evaluated. It increases when the structure changes from the random structure to the graphite structure with many defects. After the change, it decreases with decreasing the defects in graphite structure. Thus, the most reactive material should consist of the graphite structure with many defects.KEY WORDS: natural and synthetic graphite; coke; wood charcoal; bamboo charcoal; Raman spectroscopy; reactivity with CO 2 ; new parameters to evaluate structure; structure change during heat treatment; highly reactive material.

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Coke is one of the important materials for ironmaking process such as blast furnace as it plays multiple roles by providing heat energy, performing the role of reducing agent and spacer for maintaining the blast furnace permeability. Due to increasing economic and environmental concerns, there is growing interest in reducing coke consumption by using innovative blast furnace operations such as accelerating coke reactions at relatively lower reactions. In an operating blast furnace, coke carbon structure is continuously modified as it descends towards lower parts of a blast furnace. Evolution coke carbon structure is well known to influence its reactions in a blast furnace such as solution loss reaction and graphitisation. Coke quality issues are becoming increasingly pertinent as less coke would be available to supply sufficient reducing gases under proposed innovative low temperature BF operations. On the hand, graphitisation behaviour could influence its fines generation behaviour in high temperature regions of an operating blast furnace. Therefore, understanding of evolution coke carbon structure at increasing temperatures is very important for the success of any new innovative blast furnace operations.Carbon structure of carbonaceous materials is often characterized by maceral analysis or reflectance measurements which are often subjective in nature and do not distinguish atomic level differences of different carbon types. Recently, advanced analytical tools such as the X-ray Diffraction or Raman Spectroscopy are being developed to characterize carbon structure of different carbonaceous materials includ-1165

In a large proportion of the complex kanji characters resulting from the combination of two radicals, the left radical gives information about the meaning of the whole character, and the right one gives cues to pronunciation. In this study, this feature was exploited to investigate the relative contribution of semantic and phonological information in the process of recognizing a word written in kanji. In 2 experiments, a technique was used in which part of the target character (i.e., the left radical, carrying the semantic information; the right, phonetic radical, or a fragment) was presented shortly (60 or 180 ms stimulus onset asynchrony [SOA]) before the exposure of the whole character, which had to be named as fast as possible. Earlier exposure of the phonetic radical produced facilitation of the naming response, which was stronger at the 180-ms SOA than at the 60-ms SOA, whereas preexposure of the semantic radical had a weak facilitatory effect at the 60-ms SOA and some inhibition at the 180-ms SOA.The work reported in this article represents a contribution to the knowledge of the activation processes that underlie naming words written in a logographic system, that is, kanji characters for Japanese readers. The study deals with the recognition of single complex kanji characters. These kanji are constructed by assembling together one simple character, or radical, with another or sometimes two radicals or with the addition of some strokes. Both in the original Chinese form and in the Japanese writing system, a large number of the complex kanji, sometimes called phonetic, are characterized by a combination of a radical that gives information about the meaning with another one that gives information about the pronunciation of the character. The first is sometimes called the signific (in Japanese, hen), whereas the second is sometimes called the phonetic (in Japanese, tsukuri). In an alternative terminology, the first component is called the radical and the second is called the stem. The amount of complex Chinese characters of the phonetic type is estimated at a value close to 85% to 90% of all complex characters (Zhou, 1978) and is increasing with new words (see also Wang, 1981).The signific is not always uniquely related to a specific

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