Photoelectric properties of organic heterojunction thin film cells were investigated. Copper phthalocyanine (CuPc) and mono-azo dye (m-azo) were deposited on the Au electrode by vacuum evaporation. The cell structure was Au/m-azo/CuPc/Au, and the double layer cell was irradiated from the side of m-azo or CuPc through the semitransparent Au electrode. The dark current of m-azo in mono-layered cell under the dry air and vacuum showed the characteristic of n-type semiconductor. Wavelength dependence of photovoltages showed different behaviors for the irradiated side of m-azo and CuPc, respectively. The maximum photovoltage through the irradiation of the CuPc side was showed in the same visible wavelength region with the absorption minimum of CuPc and the absorption maximum of m-azo. On the other hand, the maximum photovoltage was showed at the relatively lower absorbance in double layer of m-azo and CuPc for the irradiation of the m-azo. The region of photocarrier generation was discussed to be the interfaces between CuPc and m-azQ from the wavelength dependence photovoltage and band model of heterojunction.

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Effect of semimicroscopic structure and rheological properties of fibrous-structured cheese on its stringiness was studied on fLheat-treated samples and stored samples. Parameters measured were as follows: area and angle 0 of stringy material, shear strength, Young's modulus, breaking strength, breaking strain, tear strength, degree of roundness of fat globules, and ratio of soluble total nitrogen to total nitrogen. Heat treatment consisted immersing the samples in temperature-controlled hot water for 30 min, then immersing the samples in water at 25 °C for 30 min, and finally measuring at 25 °C. A sample was restretched in hot water at 55 °C after heat treatment at 55 °C (restretched sample), then subjected to the same measurements as the heat-treated samples. Stored samples were kept at 20 °C for various periods, then measured in the same way as the heat-treated samples. The degree of roundness of fat globules provided quantitative informati on on the semimicroscopic structure of fibrous-structured cheese.
The degree of roundness R is defined as follows:
R= (4 π X Area of object)/(Peripheral length of object)2
An increase in the heat treatment temperature or storage period decreased the stringiness (Figs.1, 2) and anisotropy of the rheological properties (Figs.4, 5), and increased the degree of roundness (Figs.6, 7). The restretched sample after heat treatment recovered its stringiness, anisotropy and degree of roundness. On the other hand, the restretched sample after 8 weeks' storage, did not show any recovery in these properties. This is because the proteins of the stored samples are decomposed by enzymes during the storage period (Fig.3). Both the rheological propetries and oriented semimicroscopic structure of fibrous-structured cheese were assumed to be necessary to reveal the stringiness.

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The homogeneous hydrogenation of cinnamic acid catalyze d by dihydrido(1, 3-diphenyltriazenido)bis(triphenylphosphine)rhodium(E) (dihydridorhodium complex) in several solvents was studied under a 1 atm pressure of hydrogen at 30 °C. The catalytic activity was found to decrease in the following order:
Dimethyl sulfoxide (DMSO)>> N, N-Dimethylformamide>Acetone- Benzene> Toluene >Tetrahydrofuran.
When DMSO was used as a solvent, the apparent overall activation energy for the hydrogenation of cinnamic acid with dihydridorhodium complex was estimated to be 45.6 kJmol^-1. A possible mechanism of the hydrogenation of cinnamic acid in the presence of dihydridorhodium complex and DMSO was proposed.

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The growth of SiC whisker from SiO( g )-CO system was examined over 1500-1600 °C. No whisker grew on the graphite plate and on the mullite tube at 1530-1600 °C. On the other hand, whisker grew on the activated charcoal in the temperature range. When 112 was added, the population of whisker increased. Size of whisker (length and diameter) grown on the activated charcoal increased as partial pressure of SiO and deposition temperature increased. Whisker size tended to decrease as partial pressure of CO increased. Growth rate of whisker decreased with elapse of reaction time. Although main crystalline phase of SiC whisker were 3 C type, the formation of 2 H type SiC was observed in the presence of H2. The temperature where disproportionation of SiO( g) occured was examined and compared with thermodynamic calculation.

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Perovskite type lanthanum chormium oxide, LaCrO₃, was prepared by pyrolysis of La (CH₃COO)(CrO_O4)⋅n H₂O (n≅2) precursor which was obtained as residue of the evaporatio n of an equimolar mixture of lanthanum acetate and chromium trioxide. The pyrolysis process was investigated by TG-DTA, XRD, IR, EPR, chemical analysis, and elemental analysis. It was found that pyrolysis reaction of the precursor is affected by partial pressure of oxygen, P02, in the atmosphere. An increase in P02 caused a change in mass losstemperature curves from a one-step to a two-steps type (Figs.3, 8). For P0₂ O.10 atm, the reaction clearly proceeded in two steps via the formation of monoclinic LaCrO4 as an intermediate (Figs.4, 5). The first step was corresponded to the combustion of acetate moiety in the precursor and crystallization to form LaCr0₄, and the second step was an elimination of the oxygen of LaCrO₄ and the phase transition to orthorhombic LaCrO₃. For P02≥0.028 atm, LaCrO₃ was formed by the one-step reaction, and the transition temperature to LaCrO3 was lower than at higher Po, (Fig.8). The intermediate compound, LaCrO₄, was obtained as a single phase at 575-625 °C in air, and it was stable at 600 °C for at least 12 h (Fig.10). Specific surface area of LaCrO₃ formed by 3 h pyrolysis at 650 °C in N2 was 19+2m₂m₂⋅g_-1. A-site subst ituted perovskite type oxide could also be prepared by a similar method: La_0.8Ca_0.2CrO₃ was prepared by pyrolysis at 800 °C for 5 h in N₂ from the precursor, which was obtained from a mixture of lanthanum acetate, calcium carbonate, and chromium trioxide (Fig.14).

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Synthesis of highly pure acetylacetone (Hacac), dipivaroylmethane (Hdpm) and ethyl acetoacetate (Hetac) chelates of yttrium(III), barium(II) and copper(II) was investigated. The chelates were synthesized by the reaction of the ligands with anhydrous yittrium chloride (in the presence of amine), barium metal or anhydrous copper(II) acetate using anhydrous solvents under dry atmosphere. Anhydrous yttrium chelats were synthesized by using triethylamine as dehydrochlorinating agent. High purity of metal chelates (Y, Ba, Cu) of Hdpm and copper chelates of Hacac and Hetac isolated in this work was confirmed by IR and ¹H-NMR spectra in addition to elemental analysis. Association and relative hydrolyzability of metal chelates were discussed according to the results on the ¹H-NMR, IR and MS measurement, the solubility and the observation during the experiment.

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In order to investigate the long-range transport of the Saharan dust over the North Atlantic Ocean and to estimate its transport amount, atmospheric dust samples were collected at Bermuda Island and Barbados Island in the North Atlantic Ocean from February 1989 to February 1991. The dust samples were analyzed by X-ray fluorescence and atmospheric concentrations of major crustal elements such as Al, Si and Fe were measured. The annual mean concentrations of Al, Si and Fe were 140 ng/m³ (n=71), 380 ng/m³ (n=65) and 120ng/m³ (n=65) at Bermuda Island and 830 ng/m³ (n=96), 1880 ng/m³ (n=90) and 550 ng/ m³(n=85) at Barbados Island, respectively. In Bermuda Island, the high concentrations o f Al, Si and Fe were observed in the summer season. Air mass trajectory patterns in Bermuda and Barbados Islands were classified with the charts of back trajectory analysis. When the air mass came from the direction of the North African Continent, the mean atmospheric concentrations of Al, Si and Fe were the highest ones in all the trajectory patterns at both islands. The air mass from the North African Continent reached frequently both islands during the summer from July to September. Therefore, it was confirmed that the Saharan dust was transported to Bermuda and Barbados Islands in the North Atlantic Ocean. By use of data of mineral dust concentrations and Box model, an annual transport amount of Saharan dust over the North Atlantic Ocean was estimated to be 123 x 10⁶ tfy.

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The bromostyrene is a new raw material for flame retardant polymers. This monomer is synthesized by the bromination of phenethyl bromide with FeC13 catalysis to give bromophenethyl bromide followed by the dehydrobromination of -CH₂-CH₂Br with CH₃CH₂OK. Since the bromination reaction has poor position selectiveity, the product of this reaction is a mixture of mono-, di- and tribromostyrenes with each of them has position isomers. By the combined use of GC-MS and several 1 and 2-dimensional NMR spectroscopies, structures. of one mono-, three di- and one tribromo-isomers in bromostyrene mixture are determined.
From the comparison of GC and ¹³C-NMR peak intensities, each GC peak is identified to these isomers, and relative GC sensitivities of each isomers are determined to 1.6, 1 and 1.5 for mono-, di- and tribromostyrenes respectively.

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Reactions of mes0-1, 2, 3, 4-tetrachlorobutene [1 a] and dl-1, 2, 3, 4-tetrachlorbutane [1 b]with patassium acetate (AcOK) in polar solvents were carried out in order to elucidate selectivity for formation of 2, 3-dichloro-1, 3-butadiene[3] and solvent effects on rate of reactions. Dehydrochlorination of [1 a] gave [3] and cis-1, 2, 4-trichloro-2-butene [4 a], which was substituted with AcOK to form cis-4-acetoxy-1, 2-dichloro-2-butene C5 a] and cis-1, 4-diacetoxy-2-chloro-2-butene [6 a] (Table 1). On the other hand, [1 b] was converted into 3 ), trans-1, 2, 4-trichloro-2-butene C4 b], trans-4-acetoxy-1, 2-dichloro-2-butene[ 5 b]and trans-1, 4-diacetoxy-2-chloro-2-butene C6b ] (Table 2). Yield of C3 was decreased with increasing polarity of solvent (Tables 4 and 5). The rate constants were correlated with dielectric constant and ET value of solvents (Fig.2). Reactivity of [1 a] with various potassium carboxylates (RCO2K) increased in the order of H <CH3 <CH₃CH₂ (CH₃), CH₃ CH₂, CH_2, CH₃=CH₃ (CH₂)(Table 6). The selectivity for formation of 3 shows in reverse order to the reactivity. These results can be interpreted by difference in pKa of conjugated acid. Yield of 3 was little affected by reaction temperature. The rate constants for consumption of [1 a] and [i b] were given by following equations.
kmeso =7.12 X 10⁷e xp(-44300/RT) (M-1 min^-1)kdl=5.7 4 X 10¹²exp(-76400/RT) (M-1 min^-1)

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The reactions of phenyltriisocyanatosilane (PTIS) with ethanol and amin es were investigated to obtain polysilazanes as a precursor for silicon nitride, binders or additives. The reaction of PTIS with ethanol at 0°C in the presence of a catalytic amount of triethylamine formed alkoxyisocyanatosilane derivatives PhSi(NCO)_3-n_(0Et)_n(n=1-3). The derivative (n=2)reacted with amines RNFI, (R=Me, Pr) to give the adduct PhSi(NHCONHR)(0Et)₂. On the reaction in the molar ratio r(NH₃/PTIS) =2, 4, 6 at-60°C, on the other hand, polysilazanes with a good spinnability (r=4, 6) and film formation (r=2) were obtained. In order to investigate the formation mechanism and structure of polysilazanes, the intermediate oligosilazane formed on the reaction (r=4) at 60°C was reacted with methylamine, followed by the reaction with N, O-bis(trimethylsilyl)acetamide to isolate as a stable derivative. It was confirmed that the intermediate was oligosilazane [-Ph(NCO)SiNH-]_n, (n=3-4) which underwent condensation during the isolation process at room temperature or by heating at 70° to give polysilazanes with n=7-8 or M=2200, respectively. On the reaction (r=6), the polysilazane having partly unreacted isocyanato group and probably sesquisilazane-like structure was obtained. Thermal property of these polysilazanes was also investigated.

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Hydration of a-terpinene [1], isolimonene[2], terpinolene [3]7 2-carene [4 ], 3-carene C5 J and sabinene [6 ] in the presence of synthetic zeolites was studied. Hydration of monocyclic monoterpene hydrocarbons [1], [2] and [3] in the presence of high-silica zeolites as HSZ-320 HOA or HSZ-600 HOA gave p-methylacetophenone [10] and p-cymen-8-ol [11] as the main products. Terpinen-4-ol [13] was obtained from C 2 J with 82% selectivity by hydration in the presence of HSZ-640 NAA zeolite. Hydration of gave [10] with Al(OH)3 or Ca(OH)2 in high 80% selectivity in the presence of 2020 AH or HSZ-360 HUA zeolites. Hydration of[ 5 ] with Al(OH)3 in the presence of 13 X zeolite afforded [14] or [17] in high selectivity (about 75%). Compound [13] was obtained from [6] as a major product by hydration with Ca(OH)2 in the presence of 13 X zeolite. t Studies on the Reaction of Terpenes in the Presence of Synthetic Zeolites. XVI.

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5, 15-Dialky1-5, 8, 15, 18-tetrahydroindolo[3, 2-a]indolo[3', 2' 5, 6]quino[3, 2-i]acridine-10, 20diones[ 6 ] were synthesized from 9-alkyl-3-aminocarbazoles [1] and diethyl 2, 5-dioxo-1, 4cyclohexanedicarboxylate[2] in three steps. The structure of [6 ]was confirmed by 400 MHz 1H-shift-correlated 2-D NMR spectra in DMSO-d 6 and so on. Visible spectra of [6] in DMF showed bathochromic shift (40 nm) compared with that of quinacridone. Furthermore, N-alkylation of [6] with alkyl halides in the presence of a phase transfer catalyst gave 5, 8, 15, 18-tetraalkyl-5, 8, 15, 18-tetrahydroindolo[3, 2-a]indolo[3', 2': 5, 6]quino[3, 2-i]acridine10, 20-diones [7] The compounds [7] having long alkyl groups were easily soluble in organic solvents.

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A coprecipitation method with Zn-DDTC complex was studied for the determination of trace amounts of chromium(VI) in natural water by graphite furnace atomic absorption spectrometry.
A 10 ml solution of zinc sulfate containing 100 mg/l zinc(II) and 5 ml of sodium acetate buffer solution were added to sample water. After adjusting pH to 3.5, 10 ml of 2% sodium diethyldithiocarbamate (DDTC) solution was added to the sample to coprecipitate chromium (VI) quantitatively. The precipitate was collected onto a membrane filter (0.45μm), then dissolved in 25 ml of ethyl acetate with stirring for 30 min to prepare the sample solution for GF-AAS. The detection limit for chromium(V1) was 0.014 μg, and the lower limit of determination was 0.047 μg.
The proposed method was not influenced by the coexistence of chromium(II), and can be satisfactorily applied to the microdetermination of chromium(VI) in natural water such as sea water and river water.

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Active-carbon-supported palladium catalysts were found to be effective in selective hydrogenolysis of dibenzofuran (DBF) to 2-phenylphenol (OPP). Good results were obtained at relatively low initial pressure of H2. On increasing the H_, pressure hydrogenation of aromatic nuclei became predominant. At 400°C and 10 kg/cm₂ of initial H2 pressure, 73.3%selectivity for OPP was obtained at 22.9% conversion of DBF. On increasing the temperature hydrogenolysis to gaseous products occurred considerably. From the change in selectivity with the DBF conversion, a consecutive reaction pathway by way of OPP leading to biphenyl and then to cyclohexylbenzene was implied.

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The adsorption of 2-naphthol-3, 6-disulfonate (NDS) and m-benzenedisulf onate (BDS) ions with the oxide solid solutions prepared by the thermal decomposition of synthetic Mg-Al and Zn-Al carbonated layered double hydroxides was investigated at 25 °C. Both of the oxides were found to adsorb these anions to reconstruct the layered double hydroxide structure. In the case of the Mg-Al system, the Freundlich adsorption isotherms bent at about 0.2 mmoldm^-3 of the equilibrium concentration were obtained. This is due to the fact that the higher equilibrium pH of 11'12 causes a preferential adsorption of OH- in the low concentration region of the sulfonate ions. On the other hand, the Freundlich adorption isotherms obtained in the Zn-Al system became straight line because of the lower equilibrium pH of 9-10 (Fig.2). In both systms, the adsorbed amount of NDS was larger than that of BDS, and the interlayer distance of the solid products varied with the size and adsorbed amount of the guest anions (Fig.3).

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Tetragonal type single crystals of CeAlO₃, which are large enough for studies of crystal structures and physical properties, were successfully obtained by a flux method and by controlling Ce valency to Ce³⁺. A solute was prepared by sintering method in a graphite crucible and crystal growth was performed by using KF as a flux. All of the processes were carried out under He gas atmosphere in order to prevent oxidation. The structure have been reported to be tetragonal and/or rhombohedral based on X-ray powder diffraction studies. In this study, the Laue symmetry P 4/mmm were confirmed by means of single crystal X-ray diffractions using precession cameras and a diffractometer. The lattice parameters are a =3.7669(9), c= 3.7967(7) Å and Z=1.

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The Atomic Absorption Spectrometry (AAS) for the determination of titanium, based on ion exchange extractions of the associated ions in high alloy steels and iron sand using benzene solution of Amberlite LA-2, is described.
Titanium is extracted quantitatively in to the benzene solution of Amberlite LA-2 from O.1 M hydrofluoric acid-O.1 M hydrochloric acid mixture solution. It is back-extracted into 0.5 M hydrofluoric acid-1.2 M hydrochloric acid mixture solution.
The effect- of various other elements and acids on determ ination of titanium was examined by AAS using a dinitrogen monoxide-acetylene flame. Absorption of titanium was measured at 364.3 nm and the sensitivity of titanium was 0.75 μg per 0.01 absorptivity. Mo(VI), V(V) and Zr (VI) interfere with the determination of titanium. This method was applied to the determination of titanium in high alloy steels and iron sand with the satisfactory results.

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