The ion exchange reactions of alklai metal ions on inorganic ion exchangers were examined with solid state NMR technique in related with the hydration phenomenon of metal ions. ¹H, ⁷Li, ²³No NMR spectra were measured on lithium ion selective tin antimonate and titanium antimonate. According to the NMR study as well as ion exchange study, it was found that these exchangers had two types of ion exchange sites, one was favorable for lithium ions and the other had poor selectivity for lithium and sodium ions. In the former site, lithium ions were adsorbed by dehydrating water molecules. The second and the third exchangers examined were monoclinic antimonate and cubic niobate, both are very selective for lithium ions. It was found that only lithium ions were selectively adsorbed on these ion exchangers by dehydrating their hydrated water molecules. Small space of ion exchange site result in the selectivity. The last ion exchanger was cubic ammonium molybdate, in which potasium ions as well as ammonium ions are very selective. Two types of ion exchange sites were found to present due to the I1 NMR study. One site, the population was about 25%, was found to adsorb any kind of univalent ions. The other site was very favorable for potassium ions and could not adsorb hydrogen ions. The phenomenon was well accountable from the analogy of hydration properties of metal ions in aqueous solution.

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Control of layer charge has been undertaken for expandable fluorine micas utilizing a fixation method with interlayer A13+ cations and the conception of effective layer charge (E. L. C. ) have been brought. Sodium-fluorine mica having layer charge of 0.8 (Na_0.8Mg_2.2Li_0.8Si₄O₁₀F₂) and it's Li+-exchanged form, i. e. Li-fluorine mica, were used as mothe r crystals for layer charge-controlling. Partially exchanged Al³⁺in Li-mica is completely fixed into hexagonal holes of silicate layer and loses it's exchangeability upon heating at 500 °C, so that the net negative charge, i. e. E. L. C., which is defined as the difference between the original layer charge and the fixed Al³⁺-positive charge per unit silicate layer, is controllable with interlayer cation ratios of Al³⁺/Li+. The partially Al³⁺-exchanged Li-micas show limited swelling but they recover free swelling upon heating at 500 °C. This is caused by the remaining interlayer Li+ cations and reduction of layer charge through Al3+-fixation. The content of intercalated hydroxoaluminum polycations decreases linearly with decreasing E. L. C., indicating that the intercalated pillar density is controllable for cross-linked mica complexes. Thermal durability of the complexes decreases with decreasing E. L. C. because the pillar density in the complexes having smaller values of E. L. C. is too low to stabilize the intercalated structure at high temperatures, resulting in the collapse of regular stacking sequences and the smaller quantity of micropores in interlayer region of the complexes. The basal spacings of the complexes heated at 500 °C are 17.7 A, not depending on E. L. C., while specific surface areas and micropore volumes of them show dependency on E. L. C. due to the changes of pillar density and the difference of thermal behaviors of intercalated substances, showing a maximum at E. L. C. of 0.5.

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On adding a small amount of Triton X-100, a nonionic surfactant to an aqueous solution of some divalent or trivalent metal ions containing potassium thiocyanate in excess, various colored tarry gels deposited. The colors were as follows: Ti(III1) violet, VOID yellow brown, Cr(III) purple, Fe(III) deep red, Fe(II) white, Co(II) deep blue, Cu(II) dark brown, and Zn(I0 white. Scan), Mn(II), and Ni(II) ions did not form such gels. These gels w ere stoichiometric adduct such as K₂[M^II(NCS)₅]⋅2Triton, and K₂[M^III(NCS)₅]⋅2Triton. The compositions remained essentially constant on preparing with various concentrations of potassium thiocyanate and Triton. Although such higher thiocyanato-N complexes would exist not so many in the aqueous solution, Triton might selectively bind to the complex of higher order, and the equilibria of complex formation would be forced to move. The recovery of metal ions remaining in the supernatant liquid was minimized when the Triton addition was conducted at a molar ratio of Triton/metal ion =2. Qualitative tests on the other heavy metals made it clear that 30 metal ions produced similar gels, but 20 metal ions did not. The nature of alkali-metal ion or alkaline earth-metal ion as a counter ion of thiocyanate had the serious effect on the gel yield. t Adducts of Heavy Metal Thiocyanato-N Complexes with Nonionic Surfactant. II.

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The reaction of 1-methyladenosin quaternary salt (MAD) with aqua(diethylenetriamine)platinum(II) (ADTP) was investigated by means of HPLC, UV a nd 1H-NMR under the conditions of MAD:: 1, pH 2.3 and 7.2, and at 310 K. Each reaction product was successfully separated by means of ion-pair chromatography using perchlorate as an ion-pair reagent, and the progress of the reaction was traced. The resulting reaction products were obtained by preparative HPLC under the conditions similar to analytical scale. The optimum HPLC conditions were as follows: Eluent, O.2 M NaC104 (with 0.01 M HC104)/Me0H=95/5; column, Nucleosil 5 C-18 (4.6 mm x 15 cm for analysis) and Cosmosil 5 C-18 (20 mm x 25 cm for preparative HPLC). From the column effluent, the solvent was evaporated off in the dark at 310 K in vaccuo. In many cases, '1-1-NMR measurements were successfully carried out in D20, in spite of the presence of larger amount of NaC104. In a case of difficulty, the sample described above was submitted to preparative HPLC once more to reduce the amount of perchlorate. The struct u re of the products was determined or deduced from UV and 11-1-NMR as follows: The reaction products at pH 2.3 were N 7-complex (coordinated at 7-position N), 1\6-complex (coordinated at amino group on 6-position) and N 7, N 9-complex (coordinated at 7- and 9position) (Pt/MAD=2). At pH 7.2 the main product was 1\18-complex, and the N6-methyladenosine (6-methylamino compound) and presumably N6-methyladenosine N 1-complex were produced as the small quantity of the by-products by Dimroth rearrangement. The N 7complex, which was stable at pH 2.3, decomposed gradually by Dimroth rearrangement at pH 7.2. For N6-complex diethylenetriamine and sugar moiety appeared to occupy the neighbo ring space in the solution because NOR was observed between He and H 3'.

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6-Aminohexylated macroporous glucomannan gel beads (AH-GM gel) have been developed and applied to chromatographic separation of blood coagulation factor VII in plasma cryoprecipitate fraction. Retained capacity of FVE on various kinds of AH-spherical gels was measured by a batchwise method and was apparently dependent on exclusion limit (Mlim) of the gels. AH-GM gel (Mlim 1 x107) possessed the capacity at least 10 fold higher than EAH Sepharose 4 B. The HPLC system using an AH-GM gel column also showed strong retention and go od elution recovery of FIE under the operational conditions at 0. mill flow rate.

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The phase transitions of Cd-Stearate (Cd-St) LB films (4-21 layers) were studied by Differential Scanning Calorimetry (DSC). In order to obtain the sample for DSC measurement, the LB films were formed on the Au/SiO2 substrates, and removed from the Si02 substrate with Au film. The order-disorder transitions of Cd-St LB films, ranged from 80 °C to 110 °C, were observed clearly by DSC. The thermal behavior of Cd-St LB film was different from that of the bulk material, and varied with changing the number of layers.

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We have developed a new method for the substitution of aromatic rings in calix[ 4 ]arenes via lithiation of 25, 26, 27, 28-tetrapropoxycalix[ 4 ]arenetricarbonylchromium (lCr(C0)₃). Since the Cr(CO)₃ unit activates the coordinated benzene ring, functional groups (e. g. methyl, formyl, etc. ) can be selectively introduced into the Cr(C0)₃ complexed benzene ring of cone-1. Cr (CO)₃ and 1, 3-alternate-1. Cr(C0)₃ in the yields of 75-96%. We also studied the reactivity of the 1: 2 complex, 12 Cr (CO)₃. In the distal isomer two methyl groups were introduced into the p, p' -posi t ion in 81% yield whereas in the proximal isomer several methylated products were yielded as a mixture. The substitution reaction occurred selectively at the p-position. The high para selectivity was attributed to the structural characteristics of the complexes. Thus, the present study established the novel method for selective introduction of functional gruops into the upper rim of calix[4]arenes.

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It was clarified that N-ethoxycarbonyl-N'-cyanoguanidine ( 4 ) reacted with hydroxylamine hydrochloride to afford 3-ethoxy-5-ureido-1, 2, 4-oxadiazole( 5 ) and 5-amino-3-ethoxycarbonylamino1, 2, 4-oxadiazole ( 8 ). On alkaline hydrolysis, 5 gave 5-amino-3-ethoxy-1, 2, 4-oxadiazole (10), whereas 8 gave sodium salt of 5-amino-3-carboxyamino-1, 2, 4-oxadiazole (15).8was hydrolyzed in dilute hydrochloric acid to afford 3-ethoxycarbonylamino-1, 2, 4-oxadiazol-5(4 H)-one (12), which gave 3-amino-1, 2, 4-oxadiazol-5(4 H)-one (14) on further alkaline hydrolysis.8 reacted with methylamine to give 5-amino-3-(3-methylureido)-1, 2, 4-oxadiazole (18).

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In the field of carbonization industry, it is very important to improve the quality (especially transparency) of tar acid (phenols). The technique for this purpose may be applicable to the coal liquefaction oil and the by-product oil of coal gasification. This paper describes the origin, the mechanism and the prevention of coloring of the tar acid. In order to clarify the mechanism of the coloring, the re lationship of the distillation curve of crude tar acid and the colored area was studied. It was found that the colored area are agreeable to the fraction of aniline compounds. We have developed a novel method to prevent the coloring. The process is as follows; ( 1 ) the formation of imide by reaction between 1, 2-dicarboxylic acids (for example, phthalic anhydride, 1, 2, 4-benzenetricarboxylic acid, 1, 8-naphthalenedicarboxylic acid etc. ) and a small quantity of aniline compounds in the crude tar acid; R(COOH)₂+Ar-NH₂→ R(C0)₂N-Ar, ( 2 )the elimination of aniline compounds as high boiling imides from the crud e tar acid at the distillation stage.

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The stereoselective hydrolysis of the long-chain substrate(N-dodecanoyl-D(L)-phenylalanine p-nitrophenyl ester) catalyzed by the active tripeptide(N-benzyloxycarbonyl-L-phenylalanylL-histidyl-L-leucine) was found to be controlled by changing the reaction field (temperature and the composition of coaggregates) in the hybrid aggregates composed of the nonionic micellar surfactant, α -[p-(1, 1, 3, 3-tetramethyl(butyl)phenyl]-ω -hydroxypoly(oxyethylene) Triton X 100), and the vesicular surfactants, L-α -dipalmitoylphosphatidylcholine (DPPC). The optimum composition (32 mol% DPPC/68 mol% Triton X 100) hybrid-assemblies presented the highest enantioselectivity. The markedly enhanced enantioselectivity was also observed at the phase transition of coaggregates composed of 65 mol% DPPC and 35 mol% Triton X 100.

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erovskite-type LaFe03 powders were prepared by drop coprecipitation method. An aqueous solution of La(NO₃)₃ and Fe(NO₃)₃ was dropped slowly (0.4 ml⋅ min-1) into an water-ethanolammonia solution at 40°C. The resultant gel was calcined at temperatures down to 630 °C for 2 h. The sizes of LaFe03 polycrystals were found to be as low as 13-20 nm by XRD and TEM. Their BET surface areas were measured to be 20-49 m2- g-1. In consequence of the experiment with change of coprecipitation temperature, stirring speed, dropping speed or calcination conditions of temperatures and time, the most effective factor to determine the size of ultra-fine particle were found to be the calcination temperature. In addition, the maximum surface area was obtained by short calcination time and ultrasonic stirring as secondary effects. The minimum crystallite size of LaFeO₃ was obtained around the crystallization temperature (630 °C).

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I n order to retard formation of allophanate linkages in the reaction of phenyl isocyanate with N-phenylurethane in N, N-dimethylformamide (DMF) in the presence of various inhibitors, phosphoric acid was selcted as most effective inhibitor. The reaction of bis(4-isocyanatophenyl)methane (BIM) with a diol mixture of poly(ethylene adipate) (Mn=2000) and ethylene glycol (molar ratio=1: 2; NCO/OH molar ratio=1.00) in DMF was studied to clarify the effects of addition of phosphoric acid on the concentration of allophanate linkages in resulting polyurethanes. Increase in the content of phosphoric acid results in decrease in the concentration of allophanate linkages. The addition of phosphoric acid more than 60 ppm was found to retard formation of allophanate linkages below 3 x 10-3 mmol The viscosity retention after stability test decreased with increasing the concentration of allophanate linkages in the polyurethanes.

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¹³C-NMR chemical shifts of 1, 1'-bis(o-substituted phenyl)ferrocenes were measured, and the relationships between the chemical shifts and conformation were discussed. The chemical shifts of a-protons indicated that the degree of the inclination of Cp group and Ph group in 1, 1'-bis(o-substituted phenyl)ferrocenes is almost equal to that of the corresponding mono substituted derivatives. The lower-field shifts for the ipso-carbons in 1, 1'-bis(o-substituted phenyl)ferrocenes show a steric repulsion between two Ph groups.

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