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Heaves of floors inside a reinforced concrete structure with seven stories appeared one year after its construction. Apparent repair works were applied but did not improve the situation. Year by year, the heaves had increased and it was decided to bring the problem to the court. The cause was due to the use of steel slag mixed in filled soil under the structure. Free lime in the steel slag was identified as main cause of the problem by chemical analysis.

We have been investigating zeolite synthesis from paper sludge (PS) ashes. This technique is essential from the viewpoint of recycling of wasting materials.In our previous study, the PS ashes from 20 paper mills in Fuji area of Shizuoka Pref. were examined on suitability for starting materials in the zeolite synthesis, and they were classified into 4 types of compositional ranges in terms of talc-kaolinite-calcite composition ; that is, ranges (A) and (B) were suitable for the zeolite synthesis and ranges (C) and (D) were not suitable.In this study, we selected representative 4 mills that had discharged PS corresponding to the above 4 types of compositional ranges, and the chemical and mineralogical compositions of PS from these 4 mills were analyzed for 5 days. As a result, the following conclusions were obtained.The PS samples from the mills that had initially discharged PS belonged in the ranges (A) and (B) did not change into the ranges (C) and (D) for the period of 5 days. The samples belonged in (A) and (B) showed again being suitable for the zeolite synthesis.PS discharged from a paper mill that makes products including a lot of kaolinite is suitable for the zeolite synthesis. However. PS containing too much calcite is not suitable.

石炭火力発電の廃棄物である石炭フライアッシュをアルカリ処理することにより, 陽イオン交換能, すなわち陽イオン交換容量を有する人工ゼオライトが生成する。大きな陽イオン交換容量をもつ人工ゼオライトが生成する石炭フライアッシュの成分組成を明らかにするとともに, その処理条件についても検討した。主な結果は以下の通りである。 (1) 人工ゼオライトの陽イオン交換容量は石炭フライアッシュ中の非晶質Al2O3含有量に依存する。 (2) フライアッシュ中のAl2O3含有量あるいはNa2O+K2O含有量が増加するにしたがって非晶質Al2O3含有量が増加し, それより生成した人工ゼオライトの陽イオン交換容量も増加する。 (3) 石炭フライアッシュのアルカリ処理過程でAl源を添加することにより陽イオン交換容量の大きな人工ゼオライトが生成する。

NMR of Mn 55 and N 14 in Mn 4 N were studied in its ferrimagnetic ordered phase, by using both pulsed and steady state methods. Three resonance lines are separately observed from corner site Mn (Mn-I), face-centered site Mn (Mn-II) and N. The resonance line of Mn-II is much broader than those of Mn-I and N, and has a complex structure, which can be accounted for as a powder pattern of quadrupole split lines modified by an anisotropic hyperfine interaction. The hyperfine field at Mn-I is antiparallel to, and those at Mn-II and N, are parallel to the macroscopic magnetization. Resonance frequencies of Mn-I and N decrease with temperature as usual, whereas that of Mn-II increases initially with temperature, it then follows a steep fall off. From the temperature dependences of these resonance frequencies and sub-lattice magnetizations, derived by neutron diffraction, the phenomenological isotropic hyperfine coupling constants including the transferred hyperfine coupling are estimated. Some discussions are giv...

Crystal and magnetic structures of antiferromagnetic Mn 2 N were studied by means of neutron diffraction at 290°K, 230°K, and 120°K. An orthorhombic arrangement of nitrogen atoms in the octahedral interstices of hcp manganese lattice was found. The crystal structure is ζ-Fe 2 N type whose space group is D 2 h 14 - P b n a . The intensity analysis of the diffraction pattern at 120°K yields a magnetic structure with four sublattices having the same orthorhombic unit cell as the chemical one. The magnetic moment of manganese atom was found to be 1.4±0.4µ B at 230°K and 1.6±0.4µ B at 120°K.

Paper sludge ash (PS ash) discharged from Fuji area, Shizuoka prefecture reach about 160, 000 tons/year. Therefore, the development of a technique for utilizing of PS ash is essential for recycling waste materials.PS ash collected in Fuji area has little of SiO2 and much Al2O3, CaO, in comparison with the general material of the artificial zeolite (e. g. coal fly ash). PS mainly consists of calcite, talc and kaolinite, which are originally present in paper. These minerals are converted to gehlenite, meta-kaolinite, meta-talc and lime by incineration. For this reason, the PS ash has excess Ca and low Si containt.We synthesized an artifical zeolite from the PS ash by the “Si-added method” to exclude the effect of excess calcium present in the ash. Furthermore, we studied the reaction conditions such as temperature, time and the alkali used, and found optimal synthesis conditions. Chemical and mineralogical characteristics of the synthesized zeolite were then investigated. It was found that an NaP 1-type zeolite was synthesized in an autoclave by processing at 120°C for 2 hours using a 3.5M meta sodium silicate (Na2SiO3) solution.The characteristic of Si and Al dissolved in a diluted NaOH solution shows a characteristic property of zeolite. The PS ash, coal fly ash and Shirasu were classified to S type (Si/Al 2), respectively, in terms of the characteristic solubility of Si and Al in diluted NaOH solutions. For zeolite synthesis, the PS ash was found to require more Si to meet the synthesis condition because the PS ash had a low Si and a high Ca content. As it was, Ca silicate (CSH) was generated and zeolite synthesis was prevented. Shirasu was chosen as a material providing complementary Si. Ca in the PS ash reacted successfully with the Si in the added Shirasu to generate zeolite.

Paper sludge (PS) discharged from the paper recycling process is one of the wastes requiring active development of novel technology for their complete recycling. The PS is mainly consists of organic (cellulose) and inorganic (calcite, talc. kaolinite) matters which are originally present in paper. The present study has been concerned with reaction conditions such as reaction time. solid/liquid ratio and NaOH concentration for the synthesis of zeolite from the inorganic matters by successive alkali treatment following carbonization of the organic matters. intending to develop a new use of PS. Chemical and mineralogical characteristics of the Synthesized zeolite were investigated. and the results are as follows:(1) It is ascribable to decomposition of calcite scarcely occurred in the processing carbonization due to a high partial pressure of CO2. Therefore, carbonization process is found to be effective for the synthesis of zeolite from the PS.(l2) Carbonized matter in PS was activated in the alkaline treatment. The metakaolinite in carbonized PS was converted to zeolite faster than pure metakaolinite alone by the alkaline treatment. The zeolite formed in carbonized PS, showed fine grain in crystal morphology. We found that careful control of solid/liquid ratio, NaOH concentration and reaction time in the alkali treatment process for carbonized PS could give a new composite material of active carbon and zeolite.