Features of materials production in ecological (biological) and industrial systems have been considered in view of environmental impacts based upon mainly energy consumption in both systems. Materials production in industrial systems can be characterized to be just high efficiency, high rate and mass production using processings with unlimited reaction media, raw materials and conditions thus it would bring about high environmental impacts. Materials production in ecological systems is limited in materials and energies included in reactions thus environmentally friendly in comparison with industrial systems. These difference can be interpreted by energy level of materials and reactions. In order to reduce environmental impacts, we must use solution processing in the fabrication processes of inorganic materials in their industrial fabrication.
Based upon above consideration, we have proposed "Soft Solution-Processing" where high performance inorganic materials like ceramics and / or compound semiconductors can be fabricated directly on constituent substrates in solutions. Double oxides, perovskites as BaTiO₃, SrTiO₃, Sheelites as BaWO₄, SrMoO₄, LiMO₂ (M = Co, Ni), Hydroxyapatite and some carbon materials could be prepared in film forms on constituent substrates in aqueous solutions at low temperatures of <200 ^{°C mostly 120-150 °}C. Fabrication of other materials from solution precursors are also discussed.

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Changes in pore spaces and microcracks in Shirahama sandstone subjected to slow and uniform temperature changes up to 1,000 °C have been examined using a fluorescent technique. A specimen heated up to a certain temperature was kept at the constant for 24 hours, and then cooled down to a room temperature. Texture of the specimen was observed with a microscope.
Above 500 °C, new microcracks were observed along grain boundaries. The widening of grain boundary microcracks was recognized with increasing temperature. Thermal expansion caused by the α to β transition of quartz plays the dominant role in the development of grain boundary microcracks. Above 500 ^°C, increase and enlargement of pore spaces in the matrix were also observed. The changes in matrix are caused by thermal reactions in the matrix constituent materials such as dehydration and formation of new minerals. At high temperatures, these reactions and the quartz expansion may occur simultaneously, so that microcracks and pore spaces significantly increase. Changes in physical properties such as porosity and elastic wave velocity show good agreement with the results obtained by microscopic observations.

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The boundary conditions for an axial diffusion model are overviewed and modified concerning the pulp layer in a column flotation cell. It is confirmed by the transfer function representation that the four general boundary conditions for an axial diffusion model correspond to the particular cases of Wehner and Wilhelm's, which considers not only the reaction section itself but also its fore and after ones.
Various mathematical models for the pulp layer in a column flotation cell have been proposed and the most popular one of them is an axial diffusion with first order reaction model of one stage. However, they can't estimate the behaviors of non-adhesive particles at the pulp level.
In this paper, the authors, therefore, represented the transportation of non-adhesive particles in the pulp layer of a column flotation cell by the two-stage axial diffusion with first order reaction model. The Wehner and Wilhelm's as well as Danckwerts' boundary conditions have been partly modified and then applied to the feed point, the pulp level and the tailing point of the column flotation. The proposed models with their appropriate boundary conditions make it possible to estimate the behaviors of non-adhesive particles at the pulp level.

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Kinetic behavior of lead removal from liquid copper by slag-metal reaction was investigated at 1200 °C on a laboratory scale. Various slags composed of Cu₂O, Fe₂O₃, B₂O₃ and SiO₂ were used, For Cu₂O-M_xO_y (M = B, Si, Fe) binary slags, B₂O₃ addition was most effective for the lowering of activity coefficient of PbO in slag. As a result, larger removal rate of lead from liquid copper was obtained under the experimental condition of higher contents of B₂O₃ and oxygen. SiO₂ was also an effective slag component for the lead removal, but the reaction rate was retarded by its addition to slags. The kinetic behavior of lead removal by oxidizing slags could be simulated by the reaction model based on the two film theory.

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CO₂ emission from the zinc production by recycling of the Electric Arc Furnace dust (EAF dust) was quantitatively evaluated using Life Cycle Assessment (LCA) technique. EAF dust is used as one of the raw materials in pyrolytic zinc for the smelter. So, inventories for this study such as fuel consumption of unit process and in-house electricity were established based on literatures and the public statistical data. The analysis of Life Cycle Inventory (LCI) has been conducted and as a result, the followings have been observed.
(1) The amount of CO2 emission from the pyrolytic zinc production is about 3.4 kg / kg-zinc. 40 % of the whole CO₂ emission is originated by the coke combustion in the smelting furnace. And, 20 % of the whole CO₂ emission is attributable to the separation process of EAF dust.
(2) If recycling of EAF dust to pyrolytic zinc is accelerated, the amount of CO₂ emission from zinc production is increased under the assumption that the energy consumption in the stabilization process of EAF dust is negligible. This is attributable to the difference of the energy consumption to convert to the roasted ore from the raw materials.
As a result, the present zinc recycling system from EAF dust has disadvantage from the viewpoint of the CO₂ emission. Hence, the projected recycling systems of metal recovery in the steel industry are expected to reduce the energy consumption. However, the recycling of the EAF dust must be evaluated from not only the CO₂ emission, but also impact assessment based on the resources exhaustion, the global warming, the land use and so on. Impact assessment methodology must be developed to evaluate the validity of the recycling of EAF dust.

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The precious metal has a long history of usage not only as jewelry but as the industrial materials such as catalysis, parts of electrical products and dental filling. The precious metal is extremely expensive because of the small amount of the deposit. The supply of the precious metal from recycling is more desirable than that from the ore deposit. As the method of recovery of the precious metal, precipitation-crystallization has been employed, but a lot of process steps are needed to obtain the recovery with high purity and high yield. In stead of the method mentioned above, solvent extraction with 2-ethylhexanal oxime (EHO), which is known as the selective extractant for Cu(II), Ni(II) and Pd(II), was investigated to separate Pd(II) from other metals.
It was clarified that almost perfect recovery of Pd(II) can be attained by the multistage-countercurrent solvent extraction with EHO, when Pd(II) concentration is approximately 0.005 mol / dm³ in the aqueous phase. The reaction stoichiometry is like Pd(II) : EHO : Cl^- = 1 : 2 : 2. It is impossible to strip the extracted Pd(II) with EHO by using water, but the aqueous phase containing thiourea enables the perfect stripping of Pd(II). Palladium (II)with high purity can be obtained by the scrubbing process with water to remove small amounts of other metals present as an impurity in the organic phase.

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The formation process and the internal structure of Ag-NiO composite powders prepared by spray pyrolysis were investigated. Further, the changes in structure of the composite powders were studied after heating in air and H2 gas stream. The distribution of Ni grains in the composite powders prepared by spray pyrolysis was compared with that of the usual products obtained by a mechanical mixing method.
The internal structure of Ag-NiO composite powders was observed by SEM photographs and EPMA analysis with the result; there exist Ag layer in the external region and Ag-NiO composite layer in the internal region in a single particle. The formation process of the composite powders was discussed from the observation of cross sections of the composite powders and the thermogravimetric analysis of some nitrates. The two layer structure was composed by the deposition of Ag layer in the external region with decomposition of AgNO₃ after the formation of Ag-NiO composite in the internal region.
The two layer structure of Ag-NiO composite powders did not change by heating in air. On the other hand, it was found that those structures could change and fine Ni grains were distributed uniformly after the reduction of the composite powders by heating in H₂ gas stream.

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The extraction of zinc(II) and lead(II) from sodium hydroxide solutions by Kelex 100 (7-(5, 5, 7, 7-tetramethyl-1-octen-3-ol)-8-hydroxyquinoline) in kerosene has been investigated under different conditions by addition of 2-ethylhexyl alcohol. As the results, it is found that when alcohol is added to the organic phase, the extraction of zinc(II) and lead(II) is enhanced under the limited amounts of alcohol added at low alkali concentration, although the extraction efficiency for zinc(II) is higher than that for lead(II). In contrast, those extraction is supressed by addition of alcohol at higher alkali concentrations.

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The template effects of SO₄^2-, NO₃^-, NH₃, and OH^- on the structure and morphology of Ni(OH)₂ and the effects of tartrate ions on that of Sb₂O₃ were investigated and discussed with the theoretical model that the growth units are the polyhedral structure of coordination ions. The structure and morphology of Ni(OH)₂ and Sb₂O₃ can be effectively controlled by controlling their growth units, whose dimensions and linking patterns vary with the changes of physical and chemical conditions in the aqueous solution.

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On the synthesis of mixed metal sulfides in sulfur melt, the yield is greatly affected by the addition of halides. The respective effects of PbX₂ on PbTiS₃ and BaX₂ (X = F, Cl and I) on Ba_xTiS_y yield were studied for the reaction in evacuated sealed ampoules at 350~ ^°C for 7 days. The starting materials were 0.9 Pb + 0.1 PbX₂ + TiS₂ + 50S and 0.9 BaS + 0.1 BaX2 + TiS2 + 50S. In the former reactions, PbCl2 caused a large increase in the yield at lower temperatures, viz. 350 ^°C. On the other hand, BaI₂ was most effective giving 96 % yield of Ba_xTiS_y at 450 ^°C. The yield enhancement at lower temperatures seems to be associated with the higher concentration of metal ions (Pb²⁺) or the higher solubility of PbS in sulfur melt. The main effect at higher temperatures seems to be that to suppress the sulfur vapor pressure, which reduces the formation of high volatility sulfide by-products.

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Weathered granites were studied in order to understand quantitative mineralogical changes which seriously affect the engineering properties of granite. Nishinomiya granites of different weathering grades were examined by using a X-ray diffractometer (XRD), optical microscope, electron probe micro-analyzer (EPMA). In addition, modal analysis was performed for back-scattered electron images (BSEI) of the granites.
XRD and EPMA analyses suggest that Nishinomiya granite weathering can be characterized by the plagioclase and biotite alterations to clay minerals. The mineralogical alteration series in weathered granites are 1) biotite → vermiculite → smectite → kaolin mineral, and 2) plagioclase → smectite → kaolin mineral. These mineralogical changes of the constituent minerals may be one of the major factors controlling physical and chemical properties of granite under weathering environment.
Modal analysis were performed by a fitting of probability density functions and a peak decomposition for the gray level histogram of BSE image. This convenient measurement method gives relevant modal values of constituents including alteration products, approximately equivalent to those by the conventional point counting method. It is indicated that the measurement method using BSEI is applicable to highly-resolvable quantitative-analysis of the mineralogical change in granite weathering.

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