The basic studies on negative ion chemical ionization mass spectrometry (NCIMS) and their some applications to trace analysis are presented. In NCI of halogenated compounds by electron resonance capture reactions, the correlation between both NCIMS and GC-ECD responses, the ion species, the ion abundances and the ion abundance ratios (negative/positive), etc. were discussed. It was found the negative ion formation in NCI depended upon electron affinity and activation energy, and changes in their values produced about 10QQ-fold variation in ion formation. In NCI using C1 as a reactant ion, Cl could be easily generated from chloroform, and more stabilized by addition of methane. Moreover, the spectra obtained were useful to estimate the molecular weights of thermally labile compounds. The NCI spectra of polycyclic aromatic hydrocarbons, nitroarenes, and organochlorine compounds with methane and of dioxins with oxygen were evaluated for highly sensitive and/or selective detection. Alcohols, phenols, amines, carboxylic acids, and amino acids were derivatized with various fluorine-containing reagents to find the derivatives having high electron affinity and low activation energy. The NCI techniques developed 'were applied to detect or determine trace amounts of environmental pollutants or metabolites in human plasma.

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Regioselective cleavages of 2', 3'-cyclic m onophosphateso f cytidine (Ia), uri dine (Ib), adenosine (Ic), and guanosine (Id) are achieved by cyclodextrins (CyDs) as catalysts. α-CyD promotes the cleavages of the P-O(2') bonds, resulting in the selective formation of the corresponding 3'-phosphates. At the concentration 0.05 M of α-CyD, the- selectivities are 98, 94, 76, and 67% for the cleavages of Ia-d. In the absence of α-CyD, however, concurrent cleavages of the P-0(3') bonds singificantly take place and the selectivities are only around 50%. In contrast with the regioselectiveP -0(2') cleavages by α-CyD, β-CyD and γ-CyDs enhance the cleavages of the P-0(3') bonds. The selectivity for the formation of adenosine 2'-phosphate from Ic is 88% at the concentration 0.015 M of β-CyD. The dominant effect of the molecular size of CyD on the regioselective catalysis is interpreted in terms of the difference of the structure of the CyD complex. Regioselective cleavages of the dimers and the polymers of ribonucleotides, which proceed via the cyclic phosphates as intermediates, are also successfully carried out by use of CyDs. The catalytic activities of CyDs have been promoted still more by the chemical modification.

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1, 2 -Dimetoxyethane (DME) has proauced 2, 3 -dim etox, yoxirane[1]of low concentration by autoxidation-reaction during storage for six month. The ESR spectra which can be assigned to 2, 3-dimethoxyoxirane anion radical[1-]have been obtained by electrochemical reduction of the DME containing [1] Jat, 750°C, as shown in Fig.2. The observed hyperfine splitting constants (hfsc) were nicely supported by molecular orbital (MO) calculation_of[1]The temperature dependenceo f hfsc of [ 1-] (Table 1, Fig.2) was ' discussed on the basis of cis and trans formations. The kinetic energy (δE) containing enthalpy-fluctuation due to the two inversions is estimated to be 92.9 k J/mol from Fig.3.

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The rate of thermal isomerization of merocyanine deriv atives and the mechanism of catalytic reaction with proton were investigated in various solvents. The rate contstants (kd), in methanol significantly depended on the number of sulfur atoms introduced into the merocyanine molecule. The activation energy decreased by ca.3.5 kcalmol^-1 per sulfur atom. The increase in the isomerization rate by addition of HC1 was proportional to t he proton activity in the solution as expressed by k_d=k_o+k_H⋅a_Hvu, where ko is the rate constant characteristic of the solvent used.
It was found that the activation energy of ko and kH was the same, since the activation energy of kd did not show any pH-dependence at all. This indicates that the catalytic intermediates in neutral and alkaline regions are protonated merocyanines accompanied by counter anions, MDH⁺…OR^-, rather than more weakly interacted species through hydrogen bonds, MD…HOR.
We proposed that a_o=k_o/k_H would be a convenient measure of the intrinsic proton activity in protic solvents. The possible application of the r49rocyanine photoisomers was also discussed as memory devices and proton probes for biological systems. t Spectroscopic Studies on Merocyanine Photoisomers. N.

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In order to control the properties of silica-alumina, silica-aluminas were synthesized from aluminum alkoxides and tetraalkoxysilanes in diols by chemical mixing procedure. The influence of diol structures on the specific surface areas and acidities of the silica-aluminas were investigated.
The bulkier diols generally gave the silica-aluminas with higher specific surface areas. Ethylene glycol and 1, 3-propanediol which can strongly coordinate to Si and Al, gave also the silica-aluminas with high specific surface areas. The less branched 1, 4-diols gave the silica-aluminas having extremely low specific surface areas.

According to Hammett indicators method, acidities of silica-aluminas were mainly Ho≥-8.2. Among 1, 2-diols, ethylene glycol and 1, 2-propanediol were found to give si licaaluminas with large acid amounts. Silica-aluminas prepared in 1, 3-diols had almost the same acid amounts irrespective of diol structure. It was found from the NH₃-TPD curves in the range of 200-600°C that the diol structure had big influence on the acidity of the silicaaluminas. The 1, 2-diols which tend to remain in the silica-aluminas before calcination gave silica-aluminas with high acid strength. This tendency was completely reverse when 1, 3and 1, 4-diols were used as solvents.
Accordingly, it seemed possible to control specific surface areas and acidities with this preparation method.

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The evaporation of a liquid droplet on native or hydrophobic glass, teflon and poly(vinyl chloride) plate was investigated from measurment of the contact angle and the bottom length of the droplet against time. The evaporation of a liquid droplet was found to be classified into two types (1 ) the bottom length of liquid droplet is constant until the contact angle decreases to a certain angle where the former begins to decrease with a constant contact angle and ( 2 ) the bottom length is constant while the contact angle decreases with evaporation. The evaporation of water droplet on the surface-treated glass plate, teflon and poly(vinyl chloride) is classified as type ( 1 ) and that of a droplet of water, in which powde ry concrete had been suspended, on surface-treated glass plate belongs to type ( 2 ). The rate equations of two types of evaporation were derived. These equations explain well experimental results. The receeding contact angle is discussed for the evaporation of ( 1 ). t The Appearance Mechanism of Permanent Stains on the Glass Plate. I. the type

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The evaporation of a droplet of NaC1 aq. solution in various concentrations and of 0.2wt% Na₂SiO₃ on untreated and surface-treated glass plates was investigated through the change of contact angle and the length- of the bottom of a droplet against time and the deposit of the solution droplet after evaporation was observed. The bottom length of a droplet on the untreated glass plate is constant but its contact angle decreases during evaporation. The solute was deposited on the edge of a droplet and showed caldera-like pattern after complete evaporation. The bottom length of a droplet on the surface-treated glass plate is constant, but its contact angle decreases to a certain angle and then the bottom length begins to decrease with a constant contact angle. A single agglomerate of NaCl crystals was deposited after evaporation of a droplet of NaCl aq. solution, and a caldera-like deposit was observed after evaporation of a droplet of Na₂SiO₃ aq. solution. The radius of this calderalike ring was found to be apparently shorter than that of an initial droplet. The mechanism of the evaporation and the pattern of deposit after evaporation are discussed.

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The acidities of ZSM-5 zeolites were studied comparatively using the four following methods: (1)Amine titration, (2)NH³-TPD, (3)GC-pulse adsorption of pyridine (Py) or 4methylquinoline (4 MQ), and (4)FT-IR spectroscopy. The following results were obtained;
(A) The acid amount of H-ZSM-5 determined by the methods 0-0 was found to be about 60% of the Al content of ZSM-5 (Fig.9), its acid strength having been regarded as Ha≤3.0 (Table 2). However, the acid amount determined by FT-IR spectroscopy (Method) was about 30% of the Al content (Fig.11). Therefore, the absorption coe fficients (integrated values) both for PyB (ε=1.3 cm/μmol) and for PyL (ε=1.5 cm/μmol) must be re-examined.
(B) A trace of weak acid (B+L) was observed (Fig.7) in Na-ZSM-5. This weak acidity is, in some cases, utilized as a selective acid catalyst.
(C) The acid on the external surface of zeolite, inspite of its low density, contributes considerably to the catalytic reactivity. The acidity ratio (external/total) was proportional to the surface area ratio (external/total) within 10% region.
(D) The absorbance of acidic silanol (3615 cm^-1) w as proportional to the content of Al (Fig.12). While, the absorbance of terminal silanol (3740^-1cm) was proportional to the external surface area in the range of 0 to 30 m²/g, but in higher region (≥30m²/g), the absorbance became constant (Fig.13).

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The distribution of several trace elements (Cu, Zn, Pb, Mn, and Sn) in the bottom sediments at Matoya Bay, Mie Prefecture has been studied. The concentrations of copper, zinc, lead, manganese, and tin were determined by atomic absorption spectrophotometry (AAS), after wet ashing with a mixture of hydrochloric and nitric acids (3: 1). The concentrations of copper, zinc, lead, manganese, and tin at Matoya Bay were estimated to be 1.9-49.9, 26.7.3-40.9, 86.2-350, and 2.4-10.8 μgig (dry weight), respectively. These values were significantly lower than those at Maizuru Bay, Kyoto Prefecture, while they were comparable to those at Seto Harbor, Nagasaki Prefecture. According to the distribution of trace elements, it is found that copper, zinc, and lead in the bottom sediment at the Bays behave similarly, although manganese and tin behave differently. t Studies on the Behavior of Some Trace Elements in Bay Area. BI.

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Glass transition temperature (Tg) and heat capacity change WO at the glass transition region of two kinds of quenched polymethylsiloxanes partially substituted with phenyl groups, polydimethyldiphenylsiloxane (PDMDPS) and polydimethylmethylphenylsiloxane (PDMMPS), were studied using a differential scanning calorimeter.
The T_g and the δC, were related to the weight fraction of the siloxane unit with phenyl groups.
The T_g was expressed by the equation according to Pochan et al. and the Tg's of polydiphenylsiloxane (PDPS) and polymethylphenylsiloxane (PMPS) were determined as 388 K and 330 K, respectively.
By assuming that the δC, is proportional to the free energy change (δG) at the glass transition, δ_p∝ δG=RT in f(x) was derived. Here f(x) represents a function of state depending on the content of the siloxane unit with phenyl groups.
According to the above equation, δC_p⋅T^-1 were related to the logarithmic weight fraction of siloxane unit with phenyl groups, and the δC_ps of PDPS and PMPS were determined as 0.291 and 0.371 ⋅g^-1⋅K^-1, respectively.
For both PDMDPS and PDM MPS, the δC, have a minimum values at 10 mol% of the phenyl-bearing siloxane unit content. There was not so much difference between these two polysiloxanes in the behavior of the δC_p⋅Tg^-1 in spite of the variation of the content of siloxane unit with phenyl groups. So that, it was assumed that the effect on the statistical conditions was almost the same between these two polysiloxanes partially substituted with phenyl groups, PDMDPS and PDMMPS.

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trans-Vitamin K₂(trans-VK₂), widely used as a medicine for hemostasis, is manufactured by chemical processes as its mixture with cis-VK₂, among which trans-VIC, is isolated and cis-VK₂ is discarded. During the course of our investigation on the isomerization of unsaturated bonds by a tunable laser instrument, we found that laser excitation successfully converted cis-VK₂ into trans-VK₂.
cis-VK₂ exhibits absorp tion in 200-500 nm. The irradiation of its diisopropyl ether solution (1.5 wt%, 3 ml) under nitrogen with lasers of various wavelength in 200-800 nm (10 Hz, 2 mi. /pulse, fwmh/5 ns) resulted in the isomerization to trans-VK₂. Among the lasers examined, the most efficient isomerization was accomplished with lasers in the region of 355435 nm (355, 366, 375, 404, 414 and 435 nm). Excitation of either cis- or trans-VK 2afforded their photostationary mixture comprising of trans- and cis-VK₂ in 7: 3..
It is noteworthy that the isomerization between cis- and trans-VIC, takes place highly selectively at the unsaturated bond closest to the quinone ring among four unsaturated bonds in the tetraprenyl chain. Furthermore, from the irradiation mixture, a small amount of menachromenol, a cyclized product, was isolated as a by-product. We have proposed a reaction mechanism on the photoisomerization of cis- and trans-VK₂.

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1, 1, 3, 3, 3-Pentafluoropropenesh aving a tetrahydropyrany l oxyl or methoxyethoxymethoxyl group at 2-position ([2a], [2b]) were prepared as synthons for t rifluoromethylated c ompounds.
The addition of alkoxides, amides or alkanides anion to [2 a] or[2b] followed by elimination of fluoride anion afforded the Correspondingo lefines[3] .
Trifluorolactamides [ 5 D] were prepared by the addition-eli m ination reaction of [2a ] with amide anions and the subsequent hydrolysis. When lithium (S)-(-)-1-phenylethylam ide was used, the reaction products, trifluorolactamides [ 6 ] were separated into two epimers and their configurations were determined by X-ray analysis and other methods.
Furthermore, 2-hydroxy-2-trifluoromethy1-4-alkenoica cids [10] a nd t h eir esters [11] were prepared via the addition-elimination of [2a ] or [2b] with allylic alkoxidesa nd the s ubseq uent. [3, 3]-sigmatropic rearrangement.

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When p-tolyl esters (4-CH₈C₈1-₄OCOR, R C₆H₅ [1], CH₂C₆H₅ [2] 1-C₁₀11₇[3], 3NO₂C₈H₄[4 ] ) were refluxed in chlorobenzene in the presence of AlCl₈, the corresponding 2-hydroxy-5-methylphenyl ketones were obtained in over 82% yields except t he case with p-tolyl 3-nitrobenzoate[4 ] This Fries rearrangement proceeded faster in chloroaromatic solvents (e. g., o-dichlorobenzene, p-chlorotoluene and 1, 2, 4-trichlorobenzene) (Table 1, Fig.1). On the other hand, a similar reaction of p-chlorophenyl esters (4-C1C₆H₄OCOR, R: C₆H₅ [5], CH₂C₆H₅[6] 1-C₁₀H₇[ 7 ], 2-C₁₀H₇[8], 3-NO₂C₆H₄[9] ) in boiling chlorobenzen e resulted in lower yields of the corresponding 2-hydroxy-5-chlorophenyl ketones (10.8% to 26.8 %) (Table 2). The reverse Fries rearrangement was observed in the reaction of 2hydroxy-5-chlorophenyl ketone[10] and 2-hydroxy-5-methylphenyl benzyl ketone[11] with AlCl₈ (Table 3). t Studies on the Fries Rearrangement. W.

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The reaction of isoxazoles with enamines, proceeded easily to give pyridine derivatives. For example, 1, 2, 3, 4 -tetrahydroquinoline was obtairKedb y the reaction of isoxazole with 1-(1cyclohexenyl)pyrrolidinei n THF or in dioxane under reflux in the presence of low-va lence titanium salt (prepared from titanium(IV) chloride and zinc dust) (yield: 75%). Similarly, various 3(and/or 2)-substituted pyridines were obtained from isoxazoles and β(and/or α)substituted enamines.5-Methylisoxazoles, however, gave pyridines in only poor yields.

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The 1H-NMR spectra of several [3]ferrocenophane-6-ols [3], 4 lferrocenophane-6-ols[4] and 4 Nerrocenophane-7-ols [5] in trifluoroacetic acid-d (TFA-d) were measured, and the structures of the compounds obtained by hydrolysis of the solutions in TFA-d were examined. The spectra of [3] and [4] indicated formation of stable 6-carbocations; the chemical shifts of the 6-methine and 6-methyl protons, the splittings and coupling constants of the cyclopentadienyl rings, and the long-range spin-spin coupling constants between the 6-methine and ring protons are similar to those_ of 1-ferrocenylalkyl cations. The cationic species were formed with retention of the geometric structures of the alcohols. Rearrangement of the cationic center from the 7-position to the 6-position by 1, 2-hydride shift was observed in the strong acid for [5]containing a tertiary OH. Hydrolysis of these solutions gave the corresponding 6-ols, which were dissolved in the acid to show the same sp ectra as 7-ols in TFA-d. Dissolving [5], which contains a secondary OH, in the acid did not lea d to carbocations, but formation of the species stabilized by participation of ferrocene moi ety was suggested.

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An improved method for reductive alkylation of coal using molten K in THF was applied to some coal samples.
Good yields of soluble products were obtained in the case of bituminous coals such as Yubari or Kairan, but in the case of anthracite or lignite, the yields were lower than the former.
In the case of reductive alkylation of coals, linear relationship was observed between the yield of soluble products and the ether type oxygen content of sample coals, suggesting that the yields of soluble products depend mainly on the scission of the ether linkage and the subsequent degradation of coal strucrure.
Better correlation between the ratio of the ether type oxygen content to the total oxygen (E0/0) and the yields of soluble products was obtained, which shows that both the ch emical structures of coal units and the contents of ether linkages in coals affect the yields of soluble products in the reductive alkylation of coal.

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A variety of N-(substituted phenyl)maleimides have been prepared and screened for antifungal activity using three species of fungi. All the maleimides showed antifunga l activity, and especially N-(dialkylphenyl)maleimides showed satisfactory results. T o investigate the relation between alkylated position and activity, isomers of N-(dimethylphenyl)maleimide were screened for antifungal activity. We have found that N-(2, 6-dimethylpheny)maleimede, N-(2, 4-dimethylphenyl)maleimide and N-(2, 6-diethylphtenyl)maleimide have decent activity against a variety of fungi, bacteria and yeast. N-(2, 4, 6-trichlorophenyI)maleimide showed activity against Gram-positive bacteria, but it was inactive against Gramnegative bacteria. Some Diels-Alder adducts were parpared from N-(substituted phenyl)maleimides with furan, and screened for antifungal activity. Unsubstituted compounds showed weak activity, but substituted compounds showed no activity.

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The alkylated p-cyclodextrins, heptakis(2, 3, 6-O-trialkyl)-/3-cyclodextrin[alkyl group: -(CH2)., -CH8, n=0-11], remarkably increase the polymerization rate of water-soluble viny l monomers using water-insoluble free radical initiators in the two-phase system consisting of water and organic solvent (chloroform/ligroine, volume ratio 1: 4). For example, in the polymerization of acrylamide initiated by benzoyl peroxide (BPO), the addition of about 2equivalents of alkylated /3-cyclodextrin (n=11), based on BPO, to the polymerization system increased the conversion by 10.6 times. Moreover, the conversion was accelerated by increasing the alkyl chain length of alkylated p-cyclodextrins added. In this polymerization, the lipophilic character of the alkylated p-cyclodextrins, as well as their ability to form an inclusion complex with the initiators, play an important role. Based on this finding, the alkylated p-cyclodextrins are supposed to act as the initiator carrier. That is, the waterinsoluble initiator (or radical species generated from the initiator) in the organic phase is entrapped with the lipophilic alkylated S-cyclodextrin and then effectively transferred to the aqueous phase to initiate the polymerization of water-soluble vinyl monomers.

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N-Acryloylpyrrolidine gel showed reversible therma l response, such as swelling at lower temperature and shrinkage at higher temperature: This thermosensitive property of the gels is considered due to the reversible change of hydrophobicity of the gels with temperature.
The degree of swelling decreased for the gels synthesized with higher degree o f cross-linking or with higher hydrophobic Tonomer concentration.
The amount of adsorption of benzoic aci d increased with the increase of the temperature and the content of hydrophobic monomer. The adsorption-desorption of benzoic acid was controlled by changing the temperature of the gels with controlled balance of hydrophilicity and hydrophobicity. The adsorption proceeded in the undissociated state of the substrate. The adsorption of neutral and basic compounds occurred also in the undissociated state, although the interaction was smaller than that of acidic compounds. It was suggested that the adsorption mainly based on the hydrophobic interaction, since the amount of adsorption of benzoic acid reduced by the addition of dioxane or ethylene glycol.

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Ground water pollution by organic chlorine compounds is noticed recently, and these compounds in wastewater, and solids are suspected to pollute ground water through soil. But, there is not a convenient analytical method of organic chlorine compounds in solid wastes and soil. In this researbh, a method for analysis of total organic chlorine (TOCl) or individual organic chlorine compounds in solid wastes and soil has been developed.
It was found that organic chlorine compounds could be analyzed much more conveniently and accurately by the following procedures and conditions than by the method recommended by Japan Environment Agency: ( 1 ) extract organic chlorine compounds by the addition of 20 ml ethyl acetate and ca.5 ml of water for 10 g solid sample by shaking with ultrasonic wave, ( 2) extract the organic chlorine compounds in the residue by the addition of 20 ml ethyl acetate, ( 3 ) mix the both extracts, ( 4 ) dehydrate the ethyl acetate extract by a small amount of sodium sulfate, ( 5 ) adjust the volume of the ethyl acetate extract to 50 ml, ( 6 ) measure TOC1 and the concentration of individual compounds in the extract by a total organic halogen(TOX) analyzer in the specified conditions and a gas chromatograph (GC)with ECD, respectively.
The per c ent recovery of the organic chlorine compunds were 73 10 2 % for the TOX analyzer, and 85-101 % for the GC-ECD method.

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Colloidal nickel was easily prepared by reaction of nickel bromide with zinc powder. It was an active catalyst for hydrogenation of aromatic nitro compounds and of halobenzenes. Aromatic nitro compounds were hydrogenated to give the corresponding amines in high yields in the presence of the colloidal nickel under an atmospheric pressure of hydrogen. p-Bromonitrobenzene was hydrogenated successively to afford aniline via p-bromoaniline. p-Bromoaniline and p-chloroaniline were reduced to aniline in good yields. It is suggested that the amino moiety assists the adsorption of the substrate on the surface of the metal and that it acts as an acceptor of hydrogen halide. The hydrogenation of halobenzenes gave benzene in the presence of aniline. The reactivity of halobenzenes was in the following order;1>Br>Cl.kn-abstract=

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The {ZrO(IV), Cu(II)}- and {ZrO(IV), Ti(IV)}-mixed oxalato compounds were obtained as powders by the homogenous reaction in aqueous solution of ZrOCl₂ with K₂[Cu(OX)₂] or K₂[TiO(OX)₂]. The compositions of these compounds were found to be (ZrO)₅Cu₈(OX)₁₂(OH)₂(H₂O)₂₅ ([Zr-Cu]) and (ZrO)(TiO)₂(OX)₂(OH)₂(H₂O)₇ ([Zr-Ti]), respectively. Both compounds released almost all water molecules at 200°C. In the range of 350 to 450°C, [ZrCu] formed the intermediate which had the composition of (ZrO₂)5(CuO)725010.75(CO₃)_0.75 or (Zr0)_0.75(ZrO₂)4.25(CuO)₈, (CO₃)0.75 and, above 600°C, gave (ZrO₂)₅(CuO)₈ which was merely a mixture of each metal oxide. [Zr-Ti] was found to form an intermediate of (ZrO)_0.8(ZrO₂)0.2(TiO₂)₂(CO3)0.8 or (ZrO₂)(TiO)_0.8(TiO₂)1.2(CO₃)_0.8 in the range of 350 to 550 °C. This intermediate contained a small amount of CO₂. Further heating to 650°C gave the mixed oxide, (ZrO₂)(TiO₂)₂, the structure of which was similar to that of the orthorhombic ZrTiO₄.

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Ring-opening reaction of optically active 2-ethylaziridine in water was found to give 1-(2-ethy1-1-aziridiny1)-2-butanaminek N-(2-aminobuty1)-1-(2-ethyl-1-aziridinyl-2-butanamine, and oligomers of 2-ethylaziridine. The structures of the products were elucidated on the basis of their infrared spectra and mass spectra. In this ring-opening reaction, the original configuration in the starting aziridine was retained in these products, suggesting the occurrence of N-CH1₂ bond cleavage in 2-ethylaziridine.

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Oxidation of hydrazino-1, 3, 5-triazine [1] with s everal oxidizing agents was investigated. Oxidation of [1] with nitrous acid in aqueous-chloroform media afforded triazinyl azide [2] as the sole product. On the other hand, the oxidation with such agents as mercury(II)oxide, irona(III) chloride, or bromine afforded chloro- [3], hydrazo- [4], bromo- [ 6 ], hydroxytriazine [7] and triazine [ 5 ] as products, depending on the oxidizing agent and the conditions employed. The formation of these products can be explained in terms of the formation of triazinyldiazene and its subsequent oxidation to triazinediazonium ion as reaction intermediates.

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The tautomerism of 2-(4'-substituted phenylazo)-1-naphthol (2-azo dyes) has been examined by means of electronic spectra in various solvents. With hydrogen and electron-withdrawing groups as the 4'-substituents, the hydrazone form is favored (almost 100%), while with electron-donating groups the azo form is favored to some degrees (0-58%). As examined for the 4'-OCH₃ derivative, the azo form is stabilized in pyridine, acetonp, ethanol, and methanol compared with the equilibrium in benzene, while the hydrazone form predominates in chloroform and acetic acid. Above effects of substituents and solvents have the same tendency to those observed for 4-(4'-substituted phenylazo)-1-naphthol (4-azo dyes). However, for all cases the hydrazone/azo ratios observed for 2-azo dye are much larger than those for 4-azo dye.

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