Porphyrin complexes covalently bound to macromolecules bind oxygen reversibly under various conditions. Cobalt porphyrin, fixed to disperse homogeneously and densely in soild polymer matrix, enables the facilitated oxygen transport through successive ligation in a series of complexes with the oxygen concentration gradient. Iron(II) porphyrin is oxidized immediately in an aqueous medium, but ligates oxygen molecule reversibly when it is bound to a macromolecule and accordingly incorporated in hydrophobic environment. A novel iron (II) porphyrin derivative having phospholipid-like substituents (lipid-heme) forms molecu lar assembly with phospholipids (lipid-hemefliposome), and acts as an oxygen carrier in physiological aqueous salt solution, pH 7.4, 37, 40°C, under air. The analyses of oxygen ligation to porphyrin complex is a potential methodology to clarify the molecular environment surrounding the metal complexes.

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Hydrogen-isotope exchange reaction between organic liquids (unlabeled) and tritium-labeled poly(vinyi alcohol), PVA(T), was investigated. The liquids used were m onosubstituted benzaldehydes, benzaldehyde, nitrobenzene, and benzene. It was found that only monosubstituted benzaldehydes and benzaldehyde had exchangeable 11-1 atoms. Then, the hydrogenisotope exchange reaction between PVA(T) and the excess amount of one of the monosubstituted benzaldehydes or of benzaldehyde was studied in the temperature range of 50-90°C, and the following results were obtained:
1. A hydrogen atom in a formyl group participates in the reaction.
2. The order of reactivity is benzaldehyde≈>o->m->p-tolualdehyde
3. The reactivity of the formyl group in monosubstituted benzaldehydes, except for orthosubstituted benzaldehydes, follows the Hammett rule.
4. The activation energies for the o-, m-, p-tolu aldehyde and benzaldehyde are 43, 48, 56, and 45 kJ⋅mol^-1, respectively.

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A new Raney nickel composite-coated electrode, which was prepared by a dispersion coating technique from a nickel plating bath in which Raney nickel alloy powder was uniformly dispersed, has been characterized.
SEM observation showed that the Raney nickel composite-coated layer is microscopically dendritic, although the layer is macroscopically smooth.
The roughness factor of the electrode was app roximately 8000, which was obtained from the BET surface area measurement.
ESCA study showed that the surface of the electrode is entirely covered with NiO, which presumably resulted from the exposure of the electrode to air.
An AC impedance measurement of the electrode showed tha t the phase angle of the electrode impedance which in series consisted of double layer capacitance and solution resistance was ca.45°, which is a typical behavior of a “porous electrode” towards AC.
The Tafel slope of the polarization curve for hydrogen evolution reaction in a 35 wt% NaOH solution at 90°C was ca.45 mV (2 RT 13 F). Therefore, it was found that the hydrogen evolution reaction mostly occurs on the Raney nickel catalyst not on the nickel matrix of the composite-coating layer.

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From a viewpoint of electric power storage, the following iron (III)-iron(II) redox reaction was electrochemically studied.
By use of a flow cell with gas diffusion electrodes, graphite cloth/FeCl₂ (aq), H₂ (aq)/ion exchange membrane/FeCl₃ (aq), H₂(g)/Pt loaded graphite cloth, the voltage-current charatteristics on charging and discharging of the cell were examined at 70°C as a function of (i) total Fe²⁺/Fe³⁺ concentration (1.2-2.4 mol/kgH₂O), (ii) HCl concentration (1-8 mol/kgH₂O), and (iii) the nature of the ion exchange membrane (Neosepta C-66-5 T and Nafion-125)(Figs.2 and 3).
The voltage -current characteristics were greatly influenced by the HCl concentration. A high HCl concentration favors the charging process because of the cell voltage decrease, while a low HCl concentration favors the discharging process because of the cell voltage increase. Factors (i) and (iii) did not exhibit significant effects on the voltage-current characteristics.
The power storage efficiency was estimated to be 93-68% at current density of 25-100 mA/cm² for a solution composition FeCl₂/FeCl₃/HCl=0.6 /0.6 /5.0 (mol/kgH₂O), and 90-57% at 25-100 mA/cm² for FeCl₂/FeCl₃/HCl=1.2/1.2/2.5 (mol/kgH₂O) (Table 1). If the cell is charged at higher HCl concentration provided by waste heat and discharged at a lower one, higher efficiencies (>100%) could be achieved: this has been experimentally confirmed (Fig.4).

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A hybrid-type fuel cell system consisting of power generation with the H₂/FeCl₃ couple and air oxidation of FeCl₂,
was studied. A cell was constructed with graphite gas diffusion electrodes and an ion-exchange membrane.
The fuel cell characteristics (voltage-current density relationship for Eq.1) was examined for a variety of (i) cell temperature (50-70°C), (ii) ion-exchange membranes (Neosepta C66-5 T, Nafion-125, or Aciplex K-I01), and (iii) the amount of platinum catalyst loaded on the anode (0-45 mgPt/cm²). A typical cell voltage of O.6 V and a current density of 100mA/cm² were attained at 70°C for 2 mgPt/cm². Eq.2 was examined with a bubble-type ract or for a variety of (i) bubble diameter (0.9 and O.3 mm), (ii) reaction temperature (70 and 90°C), (iii) oxygen partial pressure (0.8 and 1.8 atm), and (iv) liquid composition (1.5-3.0molFeCl₂/kgH₂O, 2.0-3.5 mol HCl/kgH₂O). The regeneration efficiency was 90% for bubble diameter 0.3 mm, 90°C, 1.8 atm O₂, 1.5 mol FeCl₂/kgH₂O, and 3.5 mol HCl/kgH₂O. Based on these experimental results, the feature of the present hybrid-type fuel cell system is discussed in comparison with the phosphoric acid type fuel cell.

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The anodic reaction of formamide (HCONH₂) on amorphous carbon was studied in a molten KH₂F₃ at 120°C using a few kinds of electrochemical methods. Pt-rod was used as the reference electrode. Anodic products were analyzed by both gas chromatography and infrared spectroscopy.
The i-E curves obtained by the cyclic voltammetry were divided into four regions with an increase in the potential. The current densities observed in both region I (below ca.2 V vs. Pt) and II (ca.2-3.5 V vs. Pt) were dependent upon the HCONH₂-concentration, and, therefore, HCONH₂ discharged mainly in these regions. Besides, the (CxF)[x>2] film was formed also on the carbon surface in the region II. In the region III (ca.3.5-6.5 V vs. Pt), HCONH₂ was fluorinated and the anode gas was composed of N₂(+O₂), CF₄, NF₃, CO₂(+COF₂), N₂O and so on. As H₂O in the melt was eliminated by formation of CO₂, the content of NF₃ in the anode gas increased with the lapse of time of electrolysis and reached the maximum value of 50.9% in the case of 4.0 mol% HCONH₂ and the current density of 5.3 mA⋅cm^-2. The anode effect occurred in the region IV (over ca.6.5 V vs. Pt). In th is system, however, the peak current density at ca.6.5 V vs. Pt on the i-E curves obtained by scanning the potential to the lower side from 9 V vs. Pt was larger than that in the molten KH₂F₃ only and it also increased with increasing the number of scan cycles. In electrolysis at the current density of 5.3-11.0 mA⋅cm^-2, the anode effect often occurred and the pulsed application of very high voltages (over 40 V) to the electrolytic cell was effective for the decomposition of (CF)n film covering the surface of the carbon anode in every occurrence of the anode effect. This procedure did not decrease the yield of NF₃. The addition of 1.0 wt% LiF to the melt was also effective for the prevention of the anode effect, but it decreased the yield of NF₃.
From these results, it is concluded that the surface of the carbon anode would be partially restored through the reduction of (CxF)n and (CF)n films with HCONH₂ and that the direct discharge of HCONH₃ as well as its electrofluorination would take place on the partially restored surface of the carbon anode. The mechanism of electrochemical fluorination of HCONH₂ is also discussed in detail.

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Effects of added K₂CO₃, CaCO₃ and BaCO₃ on the activities and selectivities of the Raney nickel alloy catalysts prepared from Ni-Cu-Al alloy were examined. Addition of K₂CO₃, CaCO₃ and BaCO₃ was carried out by impregnation of the catalyst with K₂CO₃, Ca(CH₃COO)₂ and Ba(CH₃COO)₂ aq. soln., respectively, followed by calcination in air at 500°C. The improvement of selectivity toward decomposition of methanol and the suppression of dimethyl ether formation were observed for the basic metal carbonates added catalysts (Table 1). Methanol decomposition activities of the catalyst increased with increasing amount of the added basic metal carbonates and reached a maximum at an characteristic value of content for each carbonate (Figs.1, 2, 3). The enhacement of the activity by the addition of CaCO₃ and BaCO₃ was found to be due to an increase in active sites (Figs.1, 2). For these catalysts, the crystallite size of Ni-Cu alloy decreased with increasing amount of the added carbonates (Figs.1, 2). On the other hand, the addition of K₂CO₃ caused no increase in active surface area (Fig.3). It could be presumed that K modified the active sites to enhance the activity. The carbon deposition of the catalysts after reaction at 350°C for 30 h increased with the increase of added amount of the carbonates, except the low content regions of CaCO₃ and BaCO₃ (Table 1). Deactivation was significant for the catalysts on which a large amount of carbon (Fig.4) was deposited.

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The mechanical properties such as elastic moduli, Vickers hardness, fracture toughness and percentage crack formation of alkaline earth metaphosphate glasses were systematically measured. In comparison with RO⋅P₂O₅ (R=Ca, Sr, Ba) glasses, MgO⋅P₂O₅ glass had a smaller Young′s modulus and Vickers hardness, but larger fracture toughness and crack-forming resistance values even though the ionic radius of Mg²⁺ is smaller than that of the other alkaline earth ions. This anomaly could be interpreted by considering the structure of metaphosphate glasses, where the coordination number of Mg²⁺ is four, not six as for Ca²⁺, Sr²⁺, and Ba²⁺. This structure was confirmed by considering the change of interatomic bonds of R-O and P-O, which were obtained from the three-band theory. When the other alkaline earth ions except for Mg²⁺ were mixed, mixed effects in Young′s modulus and Vickers hardness appeared faintly. On the other hand, when Mg²⁺ and one of the other alkaline earth ions were mixed, a positive mixed effect was distinctly found. This change was also interpreted in terms of the change of the coordination number of Mg²⁺.

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In order to obtain desired production conditions for prismatic a-calcium sulfate hemihydrate (α-hemihydrate) from calcium sulfite hemihydrate (sulfite), changes in crystal shapes of sulfite and α-hemihydrate and the crystal growth of α-hemihydrate during the oxidation of sulfite suspended in water with sodium citrate and nickel sulfate at 125°C and at 2 kg/cm² in pressure were studied.
Plate-like ca lcium sulfate dihydrate (dihydrate) was formed on the surface of spherical sulfite crystals at the temperatures between room temperature and 125°C. Even though the oxidation proceeded at 125°C, the plate-like dihydrate did not transfer rapidly to thea-hemihydrate. After an induction period, the dihydrate rapidly disappeared, and the prismatic ahemihydrate immediately grew in the presence of sodium citrate. Sodium citrate promoted the crystal shape change to the prismatic shape, but slowed down the precipitation of the a-hemihydrate. On the other hand, the nickel sulfate made the precipitation faster a nd promoted the crystal shape change to the needle-like shape,

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In the formation of calcium carbonate from highly supersaturated aqueous solution, stable calcite is finally formed through a process of the formation of amorphous calcium carbonate (ACC), followed by its transformation to the metastable polymorphs (vaterite at low temperatures or aragonite at high temperatures). The effect of ethylenediamine-N, N, N′, N′tetrakis(methylphosphonic acid) (EDTMP), which is one of the most widely used scale inhibitors, on the above process has been studied as functions of concentration and addition time of EDTMP and of temperature.
The effect of 10^-8.0 to 10^-4.0 M(≡mol.⋅dm^-3) of EDTMP on the change in the ion product of CO²⁺ and CO₃^2- in solution, the abundance of polymorphs and the rates of formation and transformation of CaCO₃ has been studied by means of potentiometry, X-ray diffractometry and scanning electron microscopy.
At 25.0°C, although EDTMP up to 10^-5.0 M scarcely affected the formation of ACC and its transformation to crystalline CaCO₃, the presence of EDTMP strongly inhibited the transformation from vaterite to calcite and the transformation was completely stopped at 10^-5.0 M EDTMP (Figs.1 and 2). The transformation of ACC to crystalline CaCO₃ was retarded at higher EDTMP concentrations and crystalline CaCO₃ was not formed at 10^-4.0 M (Fig.1, Table 1). The abundance of calcite formed from ACC increased with increasing EDTMP concentration until 10^-5.0 M EDTMP. Its abundance was, however, considerably lowered at 10^-4.7-10^-4.5 M EDTMP (Table 1), and a very unusual behavior has been observed for the transformation at 10^-4.7 M (Fig.1, e). The effect of EDTMP on the process at high ternperature was almost the same as that at 25.0°C, although the metastable polymorph changes to aragonite. The inhibition effect can be explained by the adsorption of EDTMP on the crystal surface of growing polymorphs.

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On the surface of Hidasuli, typical design pattern of Bizen-yaki, the formation of corundum was found in addition to quartz and iron pxide which was responsible for characteristic coloring of Bizen-yaki. It was piesumed that corundum would be formed, in the burning process, through the reaction of Bizen-clay, and potassium, a main alkali composition contained in straw ashes. In this study we investigated chemical, conditions to form the corundum in the reaction of Bizen-clay and potassium, - In the course of our study, we prepared various mixtures of Bizen-clay and potassium chloride in differekrierportion as materials, and burnt them at a constant temparature of 1300°C; then examiged the chemical products created in this process by means of X-ray diffractions. This eiamination showed: for the 3 h burning condition, the more potassium was contained, generally, the less amount of mullite appeared rapidly in the composition of the products. When the 8 wt% potassium chloride sample was used, no more formation of mullite was found out. A material containing 8to 10 wt% potassium chloride has formed the most amount of corundum in a process which was almost the same as that seen of the surface of Hidasuki; furthermdie the higher the potassium content, the more leucite was formed in the reaction of the corundum, the potassium and the quartz.
Under the conditions where the burning time was longer than 3 h, the corundum reacted with the quartz and the mullite was produced, while the forming range and amount of corundom decreased.

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An apparatus for the highly sensitive determination of residual organic carbon in highpurity water is described. Organic carbon in high-purity water is converted to carbon dioxide by chemical oxidation (K₂S₂O₈, 200°C, 30 kgf/cm²). The resulting CO² can be measured directly with a gas chromatograph. The amount of CO² is directly proportional to the concentration of carbonaceous materials in sample water. The analyzer developed consists of a degasser for removing the dissolved CO² in sample water, a reactor for converting organic material into CO², a gas/liquid separator for extraction of CO² in hot water and vapor, and a gas chromatograph for measuring CO² in extracting gas.
The dynamic range for the organic carbon determination was 1-100 ppb and the coefficient of variance at 1 ppb was 20%. The present analytical operation took 20 min per a sample.

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Organo molybdenum compounds are used as an anti-friction additive for fuel-saving engine oils. However, the anti-friction effect of the additive is deteriorated while it is used, to study the mechanism of its deterioration, the local structure around Mo atoms in the compounds have been investigated by an X-ray absorption spectroscopy (EXAFS and XANES)using a laboratory scale equipment.
The EXAFS results s uggested that the local structure of the Mo atoms in the fresh engine oils is similar to that in the molybdenum 0, 0-dialkyl phosphorodithioate (Mo-DTP)whose structure is expressed by the chemical formula as follows;
and the molybdenum compound in the oils has changed to Mo oxide in which an Mo atom is coordinated by six oxygen atoms after 2000 km running. XANES spectra of the compounds show that the coordination geometry around Mo atoms in the Mo oxide is similar to that in MoO₃ rather than MoO₂.
The deterioration of anti-friction effect of the engine oils after use coincides with Mo oxide formation.

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Autoxidation of 1, 5-diisopropylazulene C/A0 at 115°C in HMPA (or DMF) yielded 22separable products. All the compounds were monomeric and dimeric products containing an extra carbon unit ([1G], [1N], [1A₂], [1D₅], [1D₂]), naphthoquinone [1D₁], 1 H-inden-1-ones ([1D₄], [1H]), azulenylbenzofulvenes ([1B_1.2], [1C], [1D₈], [1F], [1L], [1M], [1O], [1R_1.0], and diazulenylbenzofulvenes ([1E], [1I], [1P], [1S]), structures of which were established on the basis of spectroscopic data (UV, MS, IR, and NMR). Similarly autoxidation of 1, 1′-methylenebis(3, 7-diisopropylazulene) [1A₂] at 115°C in HMPA (or DMF) gave 14separable products ([1G], [1N], [1D₅], [1D₂], [1B_1.2], [1C], [1D₃], [1F], [1L], [1M], [1O], [1R_1.2], which had been previously obtained by the autoxidation of [1A₁]. Possible re action pathways through radical reaction schemes are discussed for the formation of all the products.

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Noncatalytic liquefactions of Illinois No.6 coal in tetralin and toluene-tetralin mixture were studied at residence time of 4 to 20 min by continuous flow method. Liquefied products were fractionated into unreacted coal, preasphaltene, asphaltene and oil in order to obtain the yield-time profiles. Chemical reaction engineering analysis was performed for those profiles using the model involving all possible pathways for the formation of preasphaltene, asphaltene and oil from coal. Pseudo-first-order rate constants for each of these mechanistic steps were estimated by nonlinear regression and were compared with those of Wandoan and Morwell coals described previously. In hydrogenative liquefaction at 450°C and 20 MPa, tetralin was unusually converted to isomer 1-methylindan which causes to lose the hydrogen-donor ability as shown in Fig.4. Therefore, noncatalytic reactions with tetralin (hydrogenative liquefaction)were mainly carried out at a temperature of 400°C and pressures of 20 to 60 MPa. The rate constant estimation shown in Table 3 indicated that Illinois No.6 coal liquefaction fairly proceeds via direct formation of asphaltene from parent coal. The largest pressure acceleration for the initial stage of dissolution of Illinois No.6 coal was observed as shown in Fig.8. Comparing with the results of solvent extraction by using toluene-tetralin mixture under the same experimental conditions, the reason for this is that Illinois No.6 coal contains characteristically a fairly large amount of the weak-linked macromolecule as asphaltene, this weakbonded fraction can be easily liquefied by extraction and such a physical process is also accelerated by pressure.

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Hydroxymethylations of melamine (MH) and acetoguanamine (AGH) with formaldehyde (F) were kinetically investigated in aqueous carboxylate buffers at 40°C. For melamine hydroxymethylation, chloroacetate, 3-chloropropionate, and acetate buffers were used, and for acetoguanamine hydroxymethylation, in addition to above three buffers, formate, and propionate buffers were used. As a result, the second-order rate constant k given by the initial rate R₀=k[Ml_f]₀[F]₀ or R₀=k[AGH_f]₀[F]₀ was approximately given by k-k′ =k_HA[HA]. Here, MH_f and AGH _f show the free bases of MH and AGH, respectively, and k′ is the rate constant in unbuffered media, HA being the acidic constituent of the buffer. Next, Brφnsted plots obtained by the use of the k_HA, values, thus estimated, are linear with the slope of 0.35in each case. From this result, the general acid-catalyzed reaction mechanism was dicussed.

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Fifteen kinds of ester derivatives of fumaric acid (F), N-[p-[[(E)-3-(alkoxycarbonyl)acryloylJoxyThenzylidene]-p-alkoxyaniline (R-F-OR′), were p repared. The alkyl group (R)was ethyl, propyl, isopropyl, butyl, and s-butyl. Six kinds of alkoxyl group (OR′) from methoxy to hexyloxy were also employed. All of R-F-OMe showed only the nematic ph ase, while Et-F-OR′ with alkoxyl groups whose carbon number is 3 or above showed smectic phase other than nematic phase. From the electrooptical measurements using the He-Ne laser, electrooptical response time (τr)in nematic phase of R-F-OR′ is found to be 0.68-2.20ms (R: normal chain) and ca 40 ms (R: branched chain). The electrooptical measurement of mixed system of DOBAMBC (2-methylbutyl p-[p-(decyloxy)benzylidene]amino]cinnamate and i-Pr-F-OC₆H₁₃ⁿ was also carried out.

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Highly porous poly(styrene-co-divinylbenzene) resins were coupled with 3-chloropropionyl chloride by Friedel-Crafts reaction. The resins obtained were reacted with KSCN in DMF solution at 80°C to introduce isothiocyanato groups. The resin beads were examined for the binding ability with proteins by using batch method and column injection method. Proteins were attracted to the resin beads by the hydrophobic interaction. Subsequently proteins were strongly bound to the resin beads by formation of a stable thiourea structure between amino groups in the proteihs and isothiocyanato groups on the resin beads. These resin beads packed in a column were useful for the pretreatment (removal of proteins) of serum samples in the continuous quantitative analysis of glucose using immobilized enzymes. These resin beads were also useful as the supports of immobilized enzymes.

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The hydrolysis process of CaS Ce phosphor under a water vapour pressure was studied by means of exposing CaS: Ce to water vapour.
CaSO₄ and CaSO₃ were already obs erved on the surface of the CaS: Ce crystals at the initial period of hydrolysis. While the CaS: Ce was exposed to an atmosphere of 25°C and 40% relative humidity, water was liable to be absorbed in CaS: Ce. The surface of CaS: Ce was surrounded by water in the form of ok, and then molecular water was incorporated into the structure. With the hydrolysis being continued, Ca(OH)₂ was partially formed. A small amount of Ca(OH)₂ was changed into CaCO3 by absorbing atmospheric CO₂. Moreover, CaS: Ce was exposed to a saturated water vapour pressure at 25°C. CaS: Ce was changed into CaSO₃.1/2 H₂O via II CaSO₄. It was found that CaS was transformed to CaSO₃, 1/2 H₂O while the CaS was stored in a desicator with silica gel.

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Effects of reduction conditions on the crystal shapes and the emission intensities of CaS: Ce phosphor have been studied. Needle-like or prismatic α-CaSO₄: Ce1/2 H₂O including cerium were prepared from CaSO₄: Ce₂H₂O by using sodium succinate. After II⋅CaSO₄: Ce was obtained by calcining a-CaSO₄: Ce1/2 H₂O, CaS: Ce was prepared by the reduction of II⋅CaSO₄: Cefat 800, 900 or 1000°C in a stream of H₂, in the absence or the presence of sulfur. When It CaSO₄: Ce was reduced at 800 or 900°C, needle-like crystal shape of α-CaSO₄: Ce⋅1/2H₂O was maintained. The products, reduced at 1000°C, consisted of an aggregate of ium spherical CaS: Ce crystals. Grnular CaS: Ce was always obtained from the prismatic α-CaSO₄: Ce1/2⋅H₂O, regardless of reduction temperature. The emission intensity of CaS: Ce obtained was increased in the presence of sulfur, although the crystal shapes were not different from those obtained in the absence of sulfur.

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Syntheses and the structures of carbazole dioxazines (diindolo[3, 2-b: 3′, 2′-/n] and [2, 3-c: 2′, 3′-n]triphenodioxazines) [X b-f] whose two N positions of carbazole rings were covalently substituted by long straight chain alkyl (n-C₆-C₁₈) groups were studied. For examining the s tructt ure of [X], carbazole dioxazines in which two N positions were covalently substituted by (n-C₃-C₁₂) alkyl, groups having linear type-[6 c-e] and angular type structures [13 c-e] were synthesized from the correspoding 2, 5-bis[9-n-alkyl-2-methoxy-3-carbazolyl)amino)-3, 6-dichloro-1, 4-benzoquinoneg [12 c-d]. It was concluded that [X] does not have the linear type structure by comparing the 'properties of [6] with those of [X] Introduction of long n-alkyl groups on to the carbazole nitrogen of [X] results in lowering the melting and decomposition points, and a small bathochromic shift was observed in the visible spectra. [X] showed an improved dispersion property in poly(vinyl chloride).

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Polycondensed fused polynuclear aromatics (COPNA) resins, previously reported, were carbonized by heat treatment up to 2500°C and carbonization mechanism of COPNA resins linked with dimethyl-substituted of benzenedimethanols (DM-series) was investigated. Discussion was carried out in terms of the structure changes due to heat treatment and the results obtained were compared to those of COPNA resin linked with PXG (PXG-series).
The starting materials for carbonization were obtained by post-curing DM-series (cured at 120°C for 20 h) 200°C for 1 h.
The resultant resins were heat-treated, in a stream of nitrogen, to 1400°C at a heating rate of 5°Cimin and then from 1400 to 2500°C at 20°C/min.
PXG-series was carbonized in solid state through the whole process, while DM-series completely liquefied at 450°C. Optically anisotropic mesophase was observed in a microscopic section of DM-series treated at this temperature.
X-ray diffraction parameters of DM -series chars produced by the heat treatment at various temperature up to 2500°C revealed that they behave like graphitizing carbon: at 2500°C, d₍₀₀₂₎=O.3 36 nm, Lc = 33 rim.

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The interlayer spacing of aluminum-montmorillonite swollen with water (1.13 g-Water/g-Clay) was measured by small angle X-ray scattering. The interlayer spacing of aluminummontmorillonite paste was 19.2Å, and that in the frozen state was 17.3Å. The heat of fusion obtained by differential scanning calorimetry (DSC) was by 72 J/g-Clay smaller than that calculated by assuming that water in the paste was totally frozen. These rcstilts suggested that the amount of unfrozen water at 200 K in aluminum-montmorillonite was 0.22 g-Water/g-Clay.

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