Analytical chemistry, or analytical science when it refers to wider meaning, is one of the important tools of our society. This means that the analytical chemistry is used in forensic analysis, trading, industry, and food analysis. However, we sometimes tend to think little of analytical chemistry, and consequently, we lose many lives, money, or resources. I exemplify these in the present report: international coal trading, cosmetics, germs, the Product Liability Law, several forensic analyses, doping problem in Olympic games, radioactive waste, customs duties, liquor tax, the pig iron suit, total reflection X-ray analysis, and environmental analysis.

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Rock around an underground opening such as tunnel or gateway may fail. It is usually considered that loosen or damaged zone is gradually extending with elapsed time and stability is gradually decreasing.
Recently, it was pointed out that loosen zone might be recovered in strength under a proper condition. For example, if a tunnel is supported with a material of enough strength and stiffness, loosen zone between supports and surrounding rock is compacted and consolidated. Finally, the stability will be gradually increasing.
Very few studies on strength recovery of loosen zone or failed rock have been done up to now. In this study, strength recovery of Dotan (siltstone or mudstone), Tage tuff, Kimachi sandstone and Sanjome andesite is investigated by the following experimental procedures:
1) A sample rock (a cylindrical specimen) is inserted into a small pipe and then broken by a servo-controlled testing machine.
2) Load is increased to the predetermined value and then the broken rock is compacted in the pipe.
3) The compacted rock is pulled out from the pipe, and uniaxial compression and Brazilian tests are carried out.
The experimental results indicate that:
1) Strength recovery is verified in both uniaxial compression and Brazilian tests.
2) A degree of strength recovery varies from rock to rock. In Dotan, strength recovery is most remarkable among the 4 rocks. On the other hand, Sanjome andesite shows only poor strength recovery.
3) Strength recovery is much higher under air-dried condition than water-saturated condition.

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A rock mass in in-situ is not continuum and its mechanical behaviour is strongly affected by the behaviour of the existing discontinuities, such as bedding, joints, faults and fractures. Several experimental and numerical investigations have demonstrated the influence of discontinuities on mechanical, thermal and hydraulic behaviour of jointed rock masses. It has also been indicated based on the experimental and in-situ investigations that deformational mechanism and stability of rock structures in the discontinuous rock masses extremely depend on not only the existing discontinuities but also new cracks, which are generated and progress due to loading and/or excavation.
This study is to develop an expanded distinct element method (EDEM) for simulation of generation and progress of new cracks due to shear and tension failure in the matrix blocks. As the applications, changing the depth of opening and geometrical distributions of the existing discontinuities carries out excavation simulations of deep underground opening. For the verification of the proposed approach, scale model experiments by using the base friction experiment apparatus are also carried out. Finally, effects of cable bolts on controlling deformations of the rock masses surrounding opening and movements of key blocks are discussed.

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In order to provide capability of intelligent control to the wheel loader, its motion during the scooping progress is modeled and analyzed on the basis of robotics. Motion of bucket linkage along with translation of wheel loader itself is presented by means of mechanical manipulator with three-degree-of-freedom, though the bucket linkage consists of twelve joints and ten links, and it involves three closed loops. The modeling of wheel loader enables us to plan a set of trajectories of three active joints in advance preceding scooping. The modeling provides not only kinematical information, but also a computational tool to evaluate dynamical forces to actuate all active joints in advance preceding scooping. In addition to kinematics and dynamics, the present paper also covers statics of the bucket linkage, which formulates the reaction at active joints against payload imposed on the bucket during scooping.
The results of motion analysis and statics are integrated into a computer program, which is capable of simulating the progress of scooping materials piled with various angle of slope. This paper finally describes the results obtained from a series of computer simulation in which the slope angle of piled material is varied from 25 to 45 degrees.

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Restoration of contaminated soils to an environmentally acceptable condition is important. One of the newer techniques in soil remediation is a method based on electrokinetic phenomena in soils. The technology uses electricity to affect chemical concentrations and water flow through the pores of soils. An important advantage of electrokinetic soil remediation over other in-situ processes such as soil flushing is the capability of control over the movement of the contaminants. Because the migration of the contaminants is confined by the electric field, there is little dispersion outside the treatment zone. Furthermore, the process is effective for soils with low and variable permeability.
In the present study, the distributions of cadmium concentration, pH and the electrical potential in the electrokinetic processing of kaolinite under the condition of constant current density are investigated. The results obtained in this study are summarized as follows:
Cadmium accumulates near the cathode without reducing the diffusion of hydroxide ions into the soil. The electrical potential across the soil column increases with an increase in the processing time, particularly at the time between 96 and 144 hr in this study. However, the electrical potential remains nearly constant thereafter. The increase in electrical potential across the soil column is due to the formation of cadmium hydroxide near the cathode. In keeping the catholyte pH at neutrality, cadmium migrates toward the cathode without any accumulation of cadmium near the cathode and is successfully removed at the cathode reservoir. The electrical potential across the soil decreases with the increase of the processing time and the velocity of cadmium ion decreases. It was also found that the progress of electrokinetic processing of cadmium could be grasped to a certain extent by monitoring the local voltage.

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Rice hull and straw were oxidized at temperatures in supercritical and subcritical water region to produce acetic acid by wet oxidation.
Results showed that a high concentration of acetic acid may be obtained by controlling oxidation conditions. The highest acetic acid yield was about 14 % (TOC / TOC) of the starting materials, which is almost the same as that in the case of oxidation of food wastes. It was also found that there exists a large amount of other low molecular weigh carboxylic acids than acetic acid as residual intermediate products. It seems that the additional yield of acetic acid is hardly obtained from further oxidation of residual low molecular weigh carboxylic acids since the concentration of formic and oxalic acids, which are incapable of producing acetic acid, is relatively high among them. However, the purity of acetic acid in the solution after reaction can be increased easily by increasing the reaction temperature or reaction time, because other residual low molecular weigh carboxylic acids were oxidized much more easily than acetic acid.
No significant difference in residual intermediate products and TOC decomposition was found when changing the reaction temperature from subcritical to supercritical water region over the critical point of water.

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The researchers elucidated the transformation of the state between silica / titania particles and inorganic salts during the calcination of the solid mixture of silica / potassium halide (KX) or titania / potassium halide at temperatures near 700°C. The silica sol / KX or the titania sol / KX dispersed mixture was volatized, and its dried solid was prepared for the measurement of pore size (distribution), observation of pore structure by using focused ion beam-scanning image microscope (FIB-SIM) and the determination of X-ray diffractometry (XRD). In the solid state of mixture, inorganic salt existed as a crystal was found to be transformed to the amorphous state during the heat treatment of the solid mixture. From the result of the XRD test, diffraction pattern ascribed to the inorganic salt was almost disappeared at temperatures ca. 100 ∼ 200°C lower than the melting point of it. Both silica and inorganic salt were considered to be in an amorphous state at this temperature range in the case of silica / inorganic salt system. In the titania / inorganic salt system, however, both of two components were in the crystalline state, which caused to limit of their phase separation even at temperatures near the melting point of inorganic salt. After removing of inorganic salt phase dissolved into water, porous species with having narrow pore size distribution was obtained. Through this process, during the phase separation between silica or titania and KX proceeded, the resulting porous structure was considered to form. At a calcination temperature higher than 800°C, construction of the silica or titania crystal existed as a separated domain without the formation of the porous structure.

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CO₂ emissions from the copper products manufacturing system were quantitatively evaluated using Life Cycle Assessment (LCA) technique. Copper and brass products in several shapes, copper cable and sulfuric acid were produced in this system. In this study, inventories such as the fuel consumption of the processing and the in-house electricity were based on public statistical data. The following observations were made based on LCI analysis:
(1) CO₂ emissions from the copper products in the system are in the range from 1.4 kg to 2.24 kg / kg-product, respecting the materials consumption and the energy consumption to process the products. The CO₂ emission attributable to the processing corresponds to 50 % of all emissions.
(2) The reduction effects of CO₂ emissions from the system are larger with the recycling of copper alloy scrap to the brass processing than that to the converter, if the amount of scrap consumption is fixed. The reduction is estimated to be 50,000 t-CO₂ at the point of 0.1 kg / kg-brass processing with scrap additive. However, the recycling leads to the decrease of sulfuric acid.
The recycling of scrap should be evaluated not only from the reduction of CO₂ emissions but also in terms of land use and so on.

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In order to elucidate the kinetics and mechanism of liquid antimony oxidation, experiments were conducted with air and oxygen-argon gas mixtures from the view point of an antimony recovery from antimony-bearing materials such as an used lead-battery and InSb, GaSb semiconductors. The experimental condition was in the temperature range between 973 and 1,173 K, in the oxygen partial pressure range between 0.05 and 0.25 atm.
The experimental results show that the oxidation rate increases with increasing gas flow rate, oxygen partial pressure and temperature. An evaporation study of pure water into an argon gas stream was then carried out with respect to the mass transfer characteristics in the gas phase in the reactor used for the present work. The Sherwood number is correlated by the following equation : Sh = 1.38Re^0.64Sc1/2. Then the equation was applied to analyze the oxidation kinetics of liquid antimony. The kinetic analysis shows that the mass transfer step in the gas phase controls the overall rate in the experimental range studied, except for the condition of 0.05 atm as the oxygen partial pressure.

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The behavior of the crystallization stripping of Ag carbonate and Ag-Ni composite carbonate was investigated using Versatic Acid 10 as an extractant and pressurized carbon dioxide as a crystallizing agent. The physicochemical properties such as crystal structure, thermal decomposition and distribution of Ag and Ni were also investigated on the obtained crystallized products.
The possibility of crystallization stripping of Ag and Ni from the organic phase has been confirmed by calculating the aqueous pH equilibrated with pressured carbon dioxide. The reaction of crystallization stripping of Ag and Ni depends on an extractant concentration, a pressure of carbon dioxide and a metal concentration in an organic phase. The obtained crystallized product of Ag is confirmed to be Ag₂CO₃ crystal, which is characterized by the needle like crystal or polyhedron crystal. Heating of the crystallized product of Ag in air and hydrogen causes a thermal decomposition to metal Ag powder. When the crystallization stripping is carried out from the organic phase containing Ag and Ni, the simultaneous crystallization takes place to form the composite carbonate of Ag and Ni. The composite carbonate consists of mixture of Ag₂CO₃ and NiCO₃ · 2Ni(OH)₂ · 4H₂O.

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