The amounts and forms of hydroxybenzoic acids adsorbed on goethite (GT) were examined i n aqueous suspensions and the effects of GT on formation of chloro comp ounds, chloroform (CF) and trichloroacetic acid (TCA), in water were discussed quantitatively. The analysis of adsorption behavior and FT-IR spectra of hydroxybenzoic acids in the presence of GT showed that these compounds are chemisorbed on GT. It was elucidated from FT-IR spectroscopy that m-hydroxybenzoic acid (MHBA) and p -hydroxybenzoic acid (PHBA) are adsorbed on GT, forming either monodentate complexes with an Fe atom of GT surfaces or binuclear complexes with two adjacent Fe atoms, while salicylic acid (SA) is strongly chemisorbed to form chelate complexes by coordination of carboxyli c and phenolic li gand to an Fe atom.8 El * I L. t 1992 No.1The effect of the presence of GT on the chlorination processes was found in all cases, that is based on the exchange of surface hydroxyls of GT. The other effect of the presence of GT on the chlorination processes is not remarkable in the cases of MHBA and PHBA, b ut in the cases of SA in pH 4 buffer solution, the yields of CF and TCA decreases steadily as the adsorbed SA increase. It could be concluded from the discussion on the reaction mechanism of the chlorination of hydroxybenzoic acids that this result is attributed to the chemisorption of SA on GT by chelation.

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Hydrodechlorination, dechlorohydrogenation, and isomerization of CFC 113 took place over Ni, Pd, Pt, Au catalysts supported on fluorides at 200-550 °C in the presence of hydrogen. O ver Ni/CeF₃, Ni/LaF₃, and Ni/CaF₂ catalysts, C₂C1F₃( I ) and CH, were formed selectively at <350°C and at>450°C, respectively. Compound ( I ) was a major product at 250-550°C over Ni/PbF₂ and Ni/MnF₂ catalysts. CFC 113 was converted at >150-200°C over Pd/CeF ₃and Pd/LaF₃ and the conversion increased with increasing temperature. The conversion gave a maximum of 85% at 300°C and a minimum of 10-45% at 450-500 °C and then increased again with increasing temperature. CF₃CC1H₂(II) and CF₃CC1₂H(II) were formed at <350°C and the selectivity of (IV) increased to 90% at 550°C from 50% at 150°C over Pd/CeF ₃. Compounds (II) +(IV), C₂F₃H, and ( I ) were formed successively with increasing temperature over Pd/LaF3. Pd/MnF2 was less active for the reaction. Compounds (II)+(IV) and CFHCFH(V) were major products at <250°C and at 300-500°C, respectively, over Pt/C eF3. (II) and (V) were produced slectively at <250 °C and 250-500°C over Pt/LaF₃, respec tively. A ctivity of Pt/MnF₂ was relatively low, and the high selectivity, 80-400%, was maintained at all reaction temperatures. Compound( I) was a major product at>350°C over Au/MnF 2and Au/CeF₃. No changes in acitivity and selectivity were observed after 55 h at 300°C over Ni/CaF ₂. j9-PbF₂ changed into PbC1₂ during the reaction, however, the other fluorides reacted with neither CFC 113 nor supported metals. Specific surface areas of Pd/CeF₃ and Au/CeF ₃ increased after the reaction. Dispersion of Pd increased during the reaction over fluoride supports.

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New compounds were synthesized by conventional solid state reaction at 900 °C in air using about 2: 1 powder mixture of BaCO₃ and Cu0 added about 10 mol% of MgO, CaCO₃, or Sr(NO₃)₂. Chemical composition of them was fairly different one another and shown in Table 1. About 7-8 wt% of CO, was evolved by heating them in O₂ stream at 1200 C. Moreover, they could not be synthesized successfully by firing in decarbonated atmosphereor using Ba02 as a source material inplace of BaCO₃.
Therefore CO₂ has an important role in the formatio n of these compounds. Their stability under various partial pressure of CO₂(pCO₂) was investigated at 900 °C. It was found that the new compounds were only stable under pCO2 between about 10^-4-10^-3 atm. In the atmosphere of higher pCO², they were carbonated and BaCO³ was formed. On the other hand, they decomposed to Ba2CuO³with the evolution of CO² under lower pCO ². These reactions were reversible. In conclusion, the new compounds should contain CO², probably in the form of CO^32-, in their crystal lattice, which is essential for the stabilization of the structure. The new compounds were black color and hygroscopic. Powder X-ray patterns of them could be indexed as a cubic or a tetragonal system, and their XRD data were shown in Table 2 and Table 3.

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The X-ray photoelectron spectra of Co 2p and N is level for [Co(Hdmg)₂L₂]Cl, [CoCl(Hdmg)₂2], H[CoC1₂(Hdmg)2]₂ and [Co(Hbhpn)L₂]C1₂ have been measured, where H2dmg is dimethylglyoxime, H2bhpn is N, N'-bis(2-hydroxyimino-1-methylpropylidene)-1, 3-propanediamine, and L are aniline or its derivatives. The influence of electron donating characteristics or the heat of sublimation of aniline derivative as the axial ligand on the chemical shift of binding energies was studied. The deconvolution of N 1s s pectra indicated the presence of two (for [Co(Hdmg)₂L₂]Cl, [CoCl(Hdmg), L] and [CoCl₂(Hbhpn)]) or three (for [Co(Hbhpn)L₂]C1₂) nitrogen atoms (Fig.2). These nitrogen atoms were found to be due to the amino group of aniline derivative, the hydroxyimino group of Hdmg or Hbhpn, and propanediimine of Hbhpn (Tables 2, 3). The δ Eco-N value (the binding energy difference of Co 2p 1/2 and N is of aniline derivative) was calculated. A linear correlation is observed between the δEco-N/σ, la"and δH(sub)/σ values (Fig.4), where a is Hammett substituent constant of substituted aniline derivative, and δH(sub) is heat of sublimation of aniline derivative. This fact reveals that the bonding strength of cobalt-ligand depends on the electron donating characteristic and the heat of sublimation of aniline delivatives.

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In order to isolate new complexes of [Co(taud)a] (taud: -00CCH2NH(CH2)2NH(CH2)2NHCH, C00-), several preparative reactions were attempted by using the previous reported trans(O)-[Co(taud)(H₂O)]ClO₄ as the starting materials. Subsequently, it was foun d that four kinds of taud-Co(lll) complexes could be isolated as crystals with good yields. The elemental analyses indicated that the crystals had the compositions of [Co(taud)a]Xn H2O {(a=C1-; X=0; n=0.5), (a=Br-, NCS-; X=0; n=0), (a-=NH, ; X=C104-; n=0)}. On the basis of the absorption spectrum and the infrared spectrum for th e complex of [Co(taud)(NCS)], the donor atom of the NCS- ligand is the nitrogen atom N. From th e electronic spectral data and the preparative routes for the complexes obtained, therefore, it has been found that these all complexes have the trans(0) structure and the coordination modes of taud are trans(0).

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Anion interference in response of sodium ion-selective electrodes (Na-ISEs) based on a bis (crown ether) compound was studied by measurements of electromotive force(emf) of the Na-ISEs and ATR/FT-IR spectra of the membrane surface. Sodium ion-selective membranes consisted of bis[(12-crown-4)methyl] 2-methyl-2-dodecylmalonate [bis(12-crown-4)] as a ligand, plasticizer with a variety of dielectric constants and poly(vinyl chloride). It was found that higher dielectric constant- of the plasticizer led smaller Nernstian slope and narrower linear range for the Na-ISEs. Lipophilic anions such as SCN- affected the emf-response of Na-ISEs based on bis(12-crown-4). In order to eliminate the anion interference, it was effective to use a plasticizer with low dielectric constant and an additive like sodium tetraphenylborate or its derivatives, simultaneously. It seems that the optimum plasticizer and additive are dioctyl adipate (DOA) and sodium tetrakis[3, 5-bis(trifluoromethyl)phenyl]borate (NaTFPB), respectively. The optimum concentration of NaTFPB was 5-20 mol%for bis(12-crown-4) from the point of high electivity and exclusion of anion interference. The optimized Na-ISE was applied to the analysis of control serum and patient serum samples; good reproducibility and accuracy were obtained. We concluded that the Na-ISE optimized in this study would be highly useful in the field of clinical analysis.

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A specific and sensitive high-performance liquid chromatographic method using immobilized enzyme reactor and electrochemical detector is described for the simutaneous determination of lactose and glucose. Silica beads immobilized galactosidase and glucose oxidase were packed into a short stainless steel column. The immobilized enzyme ractor column was jointed between analytical column and electrochemical detector in HPLC. Phosphate buffer solution (pH 6.5, 0.15 mol/dm3) was used as a mobile phase and was flowed at a rate of 1.1 m// min. At fitst, lactose was separated from glucose through the analytical column and enzymically hydrolyzed to β-D-glucose and D-galactose catalyzed by β-galactosidase in the immobilized enzyme column. /β-D-Glucose is oxidized to gluconolactone and hydrogen peroxide by glucose oxidase at the same eznyme column. Finally, hydrogen peroxide was amperometrically determined with an electrochemical detector. The minimum detectable amounts of lactose and glucose were found to be 10 ng and 5 ng, respectively. This method was about 10³ fold as sensitive as conventional HPLC with a differential refractive index detection. The combination of specific immobilized enzyme reactor and electrochemical detector enabled to perform highly selective detection of lactose and glucose, because the effect of interference components observed in a flow injection method was eliminated by a analytical column prior to detection. This method was successfully applied for the determination of lactose and glucose in milk, sour milk beverage and fermented

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New Synthesis of cis- δ9-tetrahydrocannabinol [2 a] and trans-49-tetrahydrocannabinol [1 b], the main physiologically active constituent of Hashish or Marijuana, is reported starting from olivetol monoacetate and 3-methyl-3-butenyl isopropyl sulfide via [2, 31sigmatropic rearrangement and intramolecular [2 +41cyclization. The [2, 31sigmatropic rearrangement of oxysulfonium ylid derived from olivetol monoacetate and 3-methyl-3-butenyl isopropyl sulfide gave a separable mixture of 2-substituted [3 a] and 6-substituted olivetol [3 b] in 74%combined yield in 1: 1.2 ratio (Scheme 3), which, after separation by column chromatography, were acrylated and transformed into sulfoxides [5 a] or [5 13], respectively. Upon heating in xylene in the presence of calcium carbonate under reflux, sulfoxides [ 5 underwent a-elimination followed by intramolecular Diels-Alder cycloaddition reaction, resulting in the formation of tetrahydrodibenzo[b, d] pyrans [7 a] or [7 b] in good overall yields (Scheme 4). These fused-ring compounds turned out to be cis indicating endo-mode cycloaddition, which is clearly contrast to unsubstituted model compound, ο-(1, 3-butadienyl)phenyl acrylate, which gave mainly a trans isomer. Dibenzopyranone [7 a] was methylated and dehydrated to give cis-δ9-cannabidiol [12 a] in good overall yield, which was converted to cis-δ9-THC [2a] on treatment with boron trifluoride etherate at 25 °C (Scheme 6). On the other hand, dibenzopyranone [7 b] was similarly converted to abn-cis-δ9-cannabidiol [12 b] (Scheme 7), which was treated with p-toluenesulfonic acid in benzene at reflux to give trans- 48-THC [1 b] (Scheme 7).

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Steroidal synthons for the preparation of active forms of vitamin D were synthesized.1 α, 3β-Diacetoxy-23, 24-dinor-5, 7-choladien-22-ol [1] was prepared starting from 22-acetoxy23, 24-dinor-1, 4, 6-cholatrien-3-one C 5 J. Enolization of [5] with isopropenyl acetate under acidic conditions, reduction of the tetraenyl acetate C 7 J with Ca(BH, ), and the treatment of the trienol [9] with PTAD (4-phenyl-3 H-1, 2, 4-triazole-3, 5(4 H)-dione) gave a DielsAlder adduc[111]. Protection of the hydroxyl group of [11] as a t-butyldimethylsilyl ether and the conversion of the acetyl group of [13] into tetrahydropyranyl ether produced [17]Epoxidation of [17] with m-CPBA and removal of the t-butyldimethylsilyl group of [19] with n-Bu4NF followed by the reduction with LiA1H4 gave the 1 a, 3 p-diol [23]. Acetylation of [23] and cleavage of the tetrahydropyranyl group of [25] yielded the target compound C 1 1 Alternatively, [13] was converted into 1 1 J in six steps through the trityl ether [31]. In a similar manner, 24-acetoxy-1, 4, 6-cholatrien-3-one[6] was transformed into 1α, 3α-diacetoxy-5, 7-choladien-24-ol C 3 J. The compounds 1 J and [3] were oxidized with pyridinium chlorochromate to afford the corresponding aldehydes [2] J and [4] .

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Hydration of d-limonene [1], 2-pinene [2], 2(10)-pinene [3], camphene [4] and tricyclene [ 5] with water in the presence of synthetic zeolites was studied. The zeolite effects on the product distribution were examined. In the HSZ-710 HOA Zeolite, d-carvone [8] was obtained from [1] as a main product, amounting to more than 75.5% of the hydration products. Hydration of[2] gave a-terpineol [7 a] as a major product. In the 2020 AH zeolite, trans-verbenol [11] was obtained from [3] as a main product, amounting to 71% of the hydration products under the optimal conditions. Hydration of [14] with CuCl2 in the presence of HSZ-620 HOA zeolite afforded predominantly isoborneol [16]. Un der particular conditions, the C16D/n-borneol [17] ratio was 2: 3 or 1: 1. Hydration of [5]with Cu(OH)2 in the presence of HSZ-640 HOA zeolite gave 1161 as a main product.

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An investigation was made on the addition reaction of camphene[1], tricyclene [2], 2-carene [3] and 3-carene [4] with alcohols (C1-C4) in the presence of synthetic zeolites. In methanol with HSZ-330 HUA synthetic zeolite at 70 °C, the addtion of [1] gave 1, 7, 7-trimethy1-2-methoxybicyclo[2.2.1]heptane [5] with high selectivity (97.5% at optimum). In 1-buthanol with HSZ-360 HUA synthetic zeolite, 1, 7, 7-trimethy1-2-butoxybicyclo[2.2.1]heptane [8] was obtained with high selectivity (high 82%) from [2] J. The addition of [3] and [4] gave 8-alkoxy-1-p-menthene compounds as the major products. These compounds were evaluated on the basis of their odor: [5], [7][12] emitted an odor that would qualify them for use as flavor materials.

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Effects of composition and sequence distribution on ionic conductivity have been investigated in the network polymer electrolytes based on poly(ethylene oxide-co-propylene oxide) (E0/PO copolymer) and lithium perchlorate (LiC1O₄). The polymer electrolytes were prepared by cross-linking reaction of E0/130 copolymer triol with 4-methyl-1, 3-phenylene diisocyanate, followed by complexation with LiC10₄. The introduction of PO units into PEO sequence and the complexation with LiC10₄ made the polymer electrolytes completely amorphous. The increase in glass transition temperature (T6) of the network polymers with increasing 82 EI * 1992 No.1LiC10₄ concentration was greatly affected by sequence distribution of the copolymer. The increase in the random copolymer networks was much larger than that in the block copolymer, and the latter increase was approximately equal to that of PEO networks, while the former increase approached that of PPO networks with increasing PO composition. Ionic conductivity of the polymer electrolytes at low LiC1O₄ concentrations was mainly affected by the EO composition of the copolymers, and the higher was the EO composition, the higher was the ionic conductivity, whereas that at high concentrations was affected not only by the EO composition but also by the difference in 7', owing to the difference in the sequence distribution. Random and block copolymer electrolytes of EO mole fraction of 0.84 had favorable ionic conductivity of 10^-5 S cm^-1 at 30 °C and 10^-7S cm^-1 even at 10 °C. Li+ transference number was 0.15 to O.4, depending on the composition and sequence distribution of the copolymers, concentration of LiC10₄, and temperature.

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The polymerization of methyl methacrylate (MMA) in the dark after UV irradiation was investigated to elucidate the nature of initiator. It was found that a mixture of dimethylketene (DMK), formaldehyde and 1, 4-dimethoxy-2, 5-dimethylbenzene was obtained photochemically from vapor of MMA exposed to UV light. The resulting mixture induced rapid polymerization of MMA. Furthermore, the presence of tetramethyl-1, 3-cyclobutanedione (TMBO) brought about a considerable reduction in UV irradiation time on the photoinduced polymerization it seems to be the reason that TMBO irradiated with UV light undergoes photolysis rapidly to DMK in a solution. These results suggest that in the presence of UV light, MMA vapor is converted into DMK which can later act as an initiator for the polymerization in the dark.

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After the activation of polypropylene fiber by ozone-oxidation, methyl methacrylate was graft copolymerized onto it. The ability of the activated fiber to initiate vapor-phase graft copolymerization was compared with that of usual liquid-phase one. The structural differences between the graft copolymers (vapor- and liquid-phase samples) prepared by the vapor -phase graft copolymerization method and the liquid-phase one were discussed from the data of the mechanical properties, the crystallinity, the double refraction, and the melting behavior by DSC. The degree of grafting for the vapor-phase sample increased with the ozone -oxidation time, the polymerization time, and the polymerization temperature, while the graft efficiency decreased. These tendencies were the same as those for the liquid-phase one. The number of branch for the vapor-phase sample was higher than that for the liquid -phase one, but the molecular weight of branch estimated by that of homopolymer was lower. The mechanical properties were improved by vapor-phase grafting and liquid-phase one, and the extent of which was small for the vapor-phase sample. The decreases in the crystallinity and the double refraction for the vapor-phase sample was less than that for the liquid -phase one. These facts suggest that the vapor-phase graft copolymerization proceeds near fiber surfa ce in our experimental conditions.

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Solvent extraction and liquid membrane transport abilities of the synthesized noncyclic diamides (L¹, L², L³, L⁴, L⁵) having pyridine ring as ligand were examined for transition metal ions (Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺) and the structural effect of the ligand on the metal binding ability was discussed. Even in acidic ran ge, L₁L₄ formed neutral complex with Cu²⁺- accompanied with the release of two amide-proton and extracted Cu²⁺ with the excellent selectivity and efficiency even in the absence of lipohilic picrate ion. The extraction and the transport abilities for CIO decreased in the following order: L²>L¹>L⁴>L³ and L³>L⁴>L¹>L², respectively. This result implies that the balance of the rates of uptake and release of CIO at the interfaces between aqueous and membrane phases is of substantial importance. The discrepancy of the orders will be explainable by the ease of the conformation change in the complex formation and the coordination ability of donor nitrogen atom of each ligand. In the extraction of the solution containing single ion species (Co²⁺, Ni²⁺, C u²⁺, Zn²⁺), L¹ and L² extracted Cu²⁺ Ni²⁺ (40%), Zn²⁺ (15%) and Co2+ (12%), while they specifically extrated Cu²⁺ from the mixed solution of these ions. L³ and L⁴ extracted only Cu²⁺ from either the single or the mixed solutions. L⁵ extracted Cu²⁺ only when picr ate ion is present at the neutral range of pH and the two amide-proton did not dissociate.

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It is well known that Rhodamine 6 G(R 6 G) dimerizes in higher concentration range than 2.5 x 10^-4 mol dm^-3 in aqueous solution and its fluorescence fades remarkably. Adding some detergents or complex forming compounds to this R 6 G dimer solution, its fluorescence intensity recovers to the level of that in alchol solution. From application of Kasha's theory on the difference spectrum between R 6 G monomer and dimer, we have estimated that the distance between xanthene planes of R 6 G is 6.28 A and these planes form the cross angle 40° in dimer molecules (Fig.2). In the case of addition of detergents to R 6 G aqueous solution the variation of R 6 G fluorescence intensity implies that the process from dimer to monomer is R 6 G₂→ R 6 G₂. Det→R 6 G in micelle. On the other hand for cyclodextrins and their derivative s and others, it cannot be contended that the additives with the large equilibrium constant for R 6 G monomer solution affect on recovering of fluorescence intensity more effectively to the dimer solution.

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A continuous filament yarn was made from the B stage resin with a softeing point of 45 °C. This resin named COPNA resin was prepared using a mixture of 1-methylnaphthalene (α-MN) and 1, 4-benzenedimethanol (PXG) of 2.5 times in molar ratio to α-MN. The continous filament yarn was immersed and cured in over 95% conce ntrated sulfuric acid for a few minutes to prevent it from melting and reacting at higher temperature. The cured filament yarn was then washed with water and dried in air. The cured filament yarn was insoluble and infusible, and did not deform even when the fiber was heated at 300°C in air. The mechanical properties o f the cured filament were measured. The tensile strength was ca.250 MPa and the Young 's modulus was ca.6 GPa. The carbonized filament yarn obtained by heating at 2500°C in a stream of argon was mechanically fragile. The filament yarn from a pitch based resin was continously made by the use of 2, 5dmithyl-1, 4-benzene dimethanol (DMPXG) as a crosslinking agent. This filament had a mechanical strength of ca.490 MPa in tensile strength and ca.5 GPa in Young's modulus by immersing and curing the filament yarn in sulfuric acid in a manner similar to theα-MN based filament yarn.

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The purpose of this study is to determine the extent of the chemical decomposition of the gel, which is formed from the soil stabilizer of urea-formaldhyde condensate type. The immersion of the gel in the various amounts of 0.0125 M H₂SO₄ solution caused the dissolution of the component such as urea, formaldhyde, hydroxymethyl goup, methylene group, and KMnO₄-consuming substances. The chemical analysis of the immersion solution reveale d that the increase in the concentration of the water-soluble substances is due to the acidcatalyzed decomposition of the gel, not to the physical dissolution of the gel.

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The procedure for the determination of trace amount of rubidium by graphite furnace atomic absorption spectrometry (GFAAS) has been examined and applied to the analysis of some natural waters including rain, lake, pond, river and hot spring water. The optimum spectral conditions for the rubidium determination are as follows: wavelength, 780.0 nm; spectral bandwidth, 1.4 nm (low); absorption signal, peak area. The t emperatures of ashing and atomization, and interferences of several acids and of coexisting major components to the absorbance of 10 ppb rubidium were examined. The most appropriate temperatures of ashing and atomization were found to be 400 °C and 1900 °C, respectively. Nitric acid and hydrochloric acid showed no significant influence on the absorbance of rubidium. The chloride interference could be suppressed by the addition of nitric acid and sodium ion into the sample solution; 0.2 mol dm-3 of nitric acid and 100 ppm of sodium ion overcame the interference up to 100 ppm of chloride. In this procedure, 20 id of the sample solution was used for one measurement and five measurements were repeated for each sample. The finally determined values were the averages of three data after the highest and lowest values were excluded. Relative standard deviation was less than 1.5% (n=40). The procedure was applied to the determination of rubidium in natural waters. Reliability of the data was examined by the addition of a certain volume of a standard rubidium solution into a natural water Whose rubidium content was already determined. The amount of rubidium in the water thus formed reached 96 to 99% of what was expected from the calculation, indicating that the data are fairly reliable. As for the samples with high rubidium contents, the results determined by the present procedure were in good agreement with those obtained by flame atomic absorption spectrometry. The detection limit was 0.03ppb (S/N = 3).

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Concentrated aqueous solutions of starch and poly( ethylene oxide) were prepared at 80 °C, and they were mixed to form simple coacervates of starch through the phase separation. This suspension was immediately cooled in an ice-containing water bath to get spherical starch microgels. The average diameter was measured to be 35 pm by particle size analyzer. The average diameter was revealed to increase with incubation time as coacervates before cooling. For example, starch microgels with average diameter of 180 pm were obtained by the cooling of the coacervates incubated at 80 °C, for 10 min.

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Holmium rhodium borides were analyzed by analytical electron microscopy. In addition to electron diffraction and electron microscopy studies, electron energy loss spectroscopy (EELS) was performed on HoRh3131.333 (nominal composition, B; 25 at%). It was found that HoRh313, 333 consists of two phases, i. e. HoRh3B (B: 20 at%) and HoRh3B2 (B: 33.3at%). These results indicate that EELS of analytical electron microscope is very useful to detect and analize for various boron compounds.

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