Egg phosphatidylcholine liposomes were coated with nat urally occurring polysaccharides bearing palmitoyl or cholesteryl group as the hydrophobic anchor. Coating the surface of liposome with these polysaccharides makes liposome mechanically stable and cell specific. An increase in the stability of the liposomes so obtained ascertained by the depression of leakage of CF from the liposomal interior and protection of enzymatic destruction of the liposome. Cell specificity of the liposomes was monitored by the specific lectin-induced aggregation, the cell uptake, and the tissue distribution in animals. Liposomes coated with amylopectin or mannan derivative showed increased endocytosis with macrophages and effective uptake by the lungs after intravenous injection into guinea pigs. Encapsulation of antimicrobial agents ( amphotericin B, ampicillin, minocycline, and sisomycin) and immunomodulator (polyanionic polymers) into these polysaccharide-coated liposomes resulted in both enhanced pharmaceutical activities, such as anti-fungal activity and macrophage activation, and decreased side effect.
In order to increase the targetability of liposome to tumor cells, monoclonal antibody fragment (anti-sialosylated Lewis^X, IgM) was conjugated with pullulan derivatives bearing maleimido group as the coupling unit. Such the immunoliposome so obtained showed significantly the specific binding to PC-9 lung squamous cell carcinoma in vitro, and selectively high accumulation in vivo at the subcutaneously implanted tumor. Encapsulation of adriamycin into the immunoliposome resulted in more significant inhibition in the tumor growth compared with simple pullulan-coated liposome without the specific sensory device.

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The chemical formation of chlorate (Cl0₃^-) by the reaction of hy pochlorite (Cl0^-) with chlorite (Cl0₂^-) has been investigated at various temperatures in the mixed solution at pH of 12.0-13.0 with an excess of Cl0₂^- to Cl0^- in order to determine the rate constant. The ionic strengths in these solutions were kept constant at 4.00 or 3.79 by adding NaCl. The permanganometry and the U. V. spectroscopy were employed in chemical analysis of the sample solutions in all cases.
The reaction of Cl0^- with Cl0₂^- was a second-order reaction, and the order with respect to each reactant separately was one. The rate constants at a given temperature were increased by increasing the ionic strength, and were 8.3 × 10^-2, 1.3 × 10^-2 and 2.3 × 10^-1 l⋅ mol^-1 ⋅h^-1 at 40.0, 45.0 and 50.0 °C, respectively, at the ionic strength of 4.00. With the results of calculations using the rate constant obtained, it was concluded that the contribution of this chemical reaction to the overall Cl0₃^- - formation during electrolysis at 1.1 V vs. S. C. E. with the anodes consisting of Ti / Pt - Ir0₂, Ti/Pd0 and Ti/Ti0₂ - Ru0₂ was negligibly small even in alkaline solutions.

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The stereoselective hydrolysis of the long-chain su bstrate (p-nitrophenyl N-dodecanoylo(L)-phenylalaninate) catalyzed by the active tripeptide (N-(benzyloxycarbonyl)-L-phenylalanyl-L-histidyl-L-leucine) was found to be controlled by changing the reaction field (the species of surfactants and the composition of coaggregates) in the hybrid aggregates composed of the cationic micellar surfactant (hexadecyltrimethylammonium bromide) and the vesicular surfactants (anionic sodium succinatedialkyl 2-sulfonatosuccinate or cationic dialkyldimethylammonium bromide).

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XP spectra of eighteen samples (Table 1) were obtained using an MgK_a X-ray source (hν=1253.6eV). The main results are as follow.
The ratio aluminum to silicon on the surface (Al/Si)_s was a little larger than that in the bulk (Al/Si)_b for all samples except HZSM-5 (Fig.1). The (Al/Si)_s, value for the HZSM -5zeolite was exceptionally smaller than the bulk value, indicating that part of Al had dissolved out during the ion-exchange process. The surface ratios cation to silicon (cation/Si)_s were larger than the bulk ratio value (cation/Si)_b (Fig.2), but the differences between (cation/Si)_s and (carion/Si)_b for the group of KZSM-5, RbZSM-5, CsZSM-5 were found to be small as well as for the group of CaZSM-5, SrZSM-5, BaZSM-5. In addition the (cation/Si), ratio for the former group was about twice as large as that for the latter group. Theser results are interpreted in terms of two cationic sites required for ion exchange of a bivalent cation.
Binding energies of Si(2p)., 0(1s), and 0(2s) decreased with the increase in the (Al/Si)_s, ratio of the sample (Figs.3 and 4), representing an increase in the concentration of Al- 0 bond in the surface phase. The existence of surface Al-0 bond was also revealed by subtrac ting the valence band spectrum of silicalite from that of zeolite (Fig.8).
The half height width of the C(1s) XPS peak could be correlated with those of Si(2p), Al(2p), and 0(1s) (Fig.6), suggesting that the surface carbon species had interacted with the cation site Al-OH⁺-Si over the zeolite surface.

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Carbon monoxide hydrogenation activity over Ti0₂- or Si0₂-supp orted Fe-Co-Ni alloy decreased with addition of Cr, Mo, or Mn due to suppressed adsorption of hydrogen and carbon monoxide on the alloy surface. However the selectivity to oxygenated compounds such as ethanol or acetone was enhanced over Cr- and Mo-added Fe-Co-Ni alloy. On the other hand, the chain growth probability was promoted over Mn added 50 Co 50 Ni. Since the vibrational frequency of adsorbed NO shifted to higher wavenumbers, the electron density of Fe-Co-Ni alloy seems to be lowered by the addition of Cr, Mo, and Mn. Dissociative chemisorption of CO is suppressed on electron deficient surface of the Fe-Co-Ni alloy, resulting in high selectivity to oxygenated compounds.

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Copper(II) ion was directly reduced in an aqueous solution to metallic copper by hydrogen gas at atmospheric pressure and at temperatures from 15 to 80°C in the presence of a Pt/PTFE (poly(tetrafluoroethylene)) catalyst. Metallic copper deposited on the surface of the catalyst was needle-like at the early stage of the reaction and grew to form foil. Many small bubbles were attached to the surface of the catalyst during the reaction. In addition, pH of the solution was lowered when copper (II) sulfate was added after hydrogen gas was bubbled into water containing only the catalyst. The reaction rate at the copper deposition amount of less than 1.5 mg/cm² was proportional to the first power of the concentration of copper(II) ion (2-20 mmol/l) and to the O.5th power of hydrogen partial pressure (10-90 kPa), and was hardly affected by the pH (1-5) of the solution.
The reaction mechanism was considered as fol lows : At the early stage of the reaction, copper(II) ion reacts with dissociatively adsorbed hydrogen on platinum and is red uced to metallic copper via copper (I) ion. At the late stage of the reaction, the metallic copper grows by a cell reaction in which platinum functions as an anode and the metallic copper as a cathode.

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Oxidation reaction of sulfide ion by molecular oxygen was studied using a catalyst with a water repellency. Sulfide ion was converted to thiosulfate ion via polysulfide ion when air was bubbled into an aqueous sodium sulfide solution in which active carbon treated with PTFE (poly(tetrafluoroethylene)) was suspended. At a PTFE content of 3 wt%, the oxidation rate was at its maximum which was more than ten times larger than that using an active carbon without PTFE. Alumina and titania showed no catalytic activity even after the PTFE treatment.

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The characteristics of five clay minerals of montmorillonites in the wet state were investigated and compared with those in the dry state. The grain size and surface structure were examined with an electron microscope. The clays of Ca and H forms remained as porus particles of several μm in the wet state, but the clays of Na form were dissociated into very fine crystalline particles below several hundred Å. Results of X-ray diffraction studies showed that the basal spacings of all the samples increased from 9.6A in the dry state to about 18.8Å or 19.6Å in the wet state. Pore size distributions and specific surface areas in the dry and wet state were determined by nitrogen and water vapor adsorption techniques and calculated by cylindrical pore and parallel plate models. The micro pore volumes of various montmorillonites increased from 25-160 mm³/g to 240-340 mm³/g, and the specific areas increased from 10-150 m²/g to 300-450 m²/g, in going from the dry to wet state.

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The solid solubility in the two barium fluoromica-potassium fluoromica systems, [barium fluorophlogopite (Ba_0.5Mg₃AlSi₃0₁₀F₂;Ba-ph) fluorotetrasilicic mica (KMg_2.5Si₄O₁₀F₂;TSM), and Ba-phfluorophlogopite(KMg₃AlSi₃O₁₀F₂; F-ph)], was investigated, by solid state reaction by, using their single crystals and polycrystalline and mixed powder specimens. Electron probe X-ray microanalysis, X-ray diffraction measurement and scanning electron microscopy were used to analyze the reaction products.
The specimens of single crystals and polycrystals in each system showed good adhesion between the two micas; the reaction process in each system was diffusion-controlled. The value of the apparent activation energy in the Ba-phF-ph system was larger than that of the Ba-phTSM system; for polycrystalline specimen the values increased as the grain size decreased. The solid solutions in each system were formed through the counter diffusion of the two cations at the interlayer site(Ba_0.5_??_K), the octahedral site[(Mg₃_??_Mg_2.5) or (Mg₃_??_Mg₃)] and the tetrahedral site[(Al⋅Si₃_??_Si₄) or (Al⋅Si₃_??_Al⋅Si₃)] in the crystal structure of mica. For the mixed powder specimens (1: 1 mol) in each system, a plot of logarighmic values of reaction period up to the end of solid state reaction vs. reciprocal absolut e tempera, ture of firing gave a straight line, and hexagonal plate crystals which were grains of micas were clearly observed at the end of the solid state reaction.

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Organic arsenic compounds, which were delivered in the atm osphere as a result of the activity of biomethylation in the environment exist in a variety of forms, such as methylarsonic acid (MMAA), dimethylarsinic acid (DMAA) and trimethyla' rsine, oxide (TMAO). In order to understand the chemical form of arsenic compounds and distribution of them in the unpolluted area, their concentrations in the marine atmosphere were measured at several sites in the North Pacific Ocean.
The arsenic compou nds were collected by high volume air sampler with a quartz fiber filter (Pallflex 2500 QAST) for 5 or 6 days at 1000 dm³⋅min^-1 air flow rate. Aerosol samples were extracted with nitric acid and hydrogen peroxide for inorganic arsenic analysis, with distilled water for organic arsenic analysis. The use of Chelex 100 resin was very effective for the elimination of foreign ions which interfered with organic arsenic analysis. Analysis of arsenic compounds in the sample solution was used by hydride generation atomic absorption spectrophotometry combined with a. cold trap of liquid nitrogen for trapping of generated arsines. This method can determine arsenic compounds separately by using the diffe rence of their boiling points of arsines generated from a sample solution, and it has a high sensitivity for arsenic analysis. The detection limits by this method were 0.7 pg/m³ for MMAA, 0.8pg/m³ for DMAA, and 0.2pg/m³ for TMAO in case of 400m³ sampling volume.
In Oahu, Hawaii, the concentration range of arsenic compounds were 40-520 pg/m³ for inorganic arsenic, 0.8-5.5 pg/m³ for DMAA, and 0.2-8.8 pg/m³ for TMAO. Methylarsonic acid was not found in any sample in Oahu, Hawaii. On the other hand, the concentration range of arsenic compounds in Yokohama, Japan were 920-5900 pg/m³ for inorganic arsenic, 1.1-22.8 pg/m³ for MMAA, O.8-5.3 pg/m³ for DMAA, and 1.6-4.8 pg/m³ for TMAO; the concentration of inorganic arsenic in Yokohama was about 15 times higher than that in Oahu, Hawaii. The inorganic arsenic concentration in other remote islands, Midway, Fanning and Chichijima in the North Pacific Ocean was almost in the same level (13-520 pg/m³) as Oahu, Hawaii. It is considered that these values are the background concentration of inorganic arsenic in the marine atmosphere. Only a slight difference of organic arsenic concentration except MMAA was found between Oahu, Hawaii and Yokohama, compared with a large difference of inorganic arsenic concentration. This fact indicates that organic arsenic, suc h as DMAA and TMAO, could be produced by biomethylation in the environment and have a homegeneous distribution in the atmosphere.

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The distribution and the pathway of source light in the new type of long capillary cell (LCC) for signal enhancement in liquid absorption spectrometry, which was proposed by the authors, were estimated by personal computer-aided Monte Carlo simulation based on a geometrical optics model of LCC. The incident light can be transmitted through the cell based on successive total reflection at the boundary between the cell wall and the atmosphere. The results of the simulation were essentially equal to those obtained by a statistica l approach using Markov process on the same subject. The simulation could not explain the res u lt why almost no signal enhancement was obtained in the actual experiment in the case that the total transmitted source light through the LCC was collected in the detector, suggesting that a considerable amount of the source light would dissipate from the expected transmission mode soon after the source, light entered the LCC. On the other hand, when the transmit ted sourcelightwas collected onlyin the liquid phase, the factors of signal enhancement corres1ponded well to those of the simulatibn.

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Photoirradiations of diazaparacycloanthracenophanes [1] gave their photocyclization products [2], and the photoproducts were reconverted into [1] upon heating at 150°C or irradiation at shorter wavelength (Scheme 1 and Figs 1-6). Substituents (R) on the bridged chains in [1] greatly affected the reactivities of [1] (Table 1). The quantum yields of photocyclization (Φ_r(N₂)) and the rate constants of photocyclization process (k_r) increased i n the order of R=-CHO, -H, -S0₂φ, -COCH₃, -CO(CH₂)₃CH₃, -COCF₃, -CH₃, -COC(CH₃)₃, while the rate constants of thermal reversion (k) decreased in the same order. The order of these reactivities was in good agreement with that of either obscurity of fine structure in electronic spectra or decrease in quantum yield of fluorescence. These differences in both reactivities and spectral properties seem to be based mainly on both the steric effect of the substituents and the difference in hybridization of nitrogen atom.

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2, 3-Dihydro-1 H-naphtho[2, 1-b]pyran-3-ol [1a] was synthes ized easily by the addition reaction of 2-naphthol (2-NP), with acrylaldehyde (AAa) followed by ring-closure reaction in the presence of sodium hydroxide in benzene.
A similar reaction of methyl substi tuted acrylaldehydess uch as crotonaldehyde (AAb) and methacrylaldehyde (AAc) with 2-NP afforded the corresponding methyl-substituted 2, 3dihydro-1 H-naphtho[2, 1-b]pyran-3-ol (1b, c).
The reaction of trans-cinnamaldehyde with 2-NP, however, afforded1 -phenyl-1H -naphtho [2, 1-b]pyran as the main product r ather than 1-phenyl-2, 3 -dihydro-1 H-naphtho[2, 1-b]pyran3-o1.
In the reaction of 1-naphthol with AAa, 3, 4-dihydro-2 H-naphtho[1, 2-b]pyran-2-ol was obtained in a 25% yield together with resinous products.
Although the dehydration and/or ring openin g of [1a] does not easily occurred under mild acidic conditions, phenalenones was formed through the rearrengement reaction by heating [1a] in 68% sulfuric acid.
Furthermore, [1a] gave not only the corresponding acetals and monothioacetals by the reaction with alcohols and thiols in the presence of acid catalyst, but also the amino derivatives by the reaction with amines in the absence of catalyst, respectively.

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The effects of surfactants on γ-ray-induced dechlor ination of carbon tetrachloride were studied in aqueous 2-propanol (25vol%) solutions containing KOH(0.2-1mol. dm^-3) by using sodium dodecyl sulfate (SDS) and hexadecyltrimethylammonium chloride (CTAC) as surfactant.
Reaction proceeded in a similar chain mechanism to that proposed for neutral and acidic solutions. In 0.4 mol⋅dm^-3 KOH solution, addition of 12-30 mol⋅dm^-3 surfactants decr eased the rate of the reaction by a factor of 1.7-2.4 as shown in Figs.6 and 7, but increased the yield of hexachloroethane by a factor of 1.2-1.7, which was produced by the bimolecular termination of ⋅CCl, radical, a chain carrier, as shown in Figs.6 and 8.

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Oxidation of phenylhydrazine with an aqueous solution of sodium periodate in the presence of eight kinds of alkenes was investigated at 40 ± 1°C, 3-anilinocyclopentene (1.1%) was obtained from cyclopentene and 3-anilinocyclohexene (0.5%) from cyclohexene. These results suggest the generation of phenylnitrene as an intermediate in these reactions (Scheme 1 routea). New 3-phenylazosubstituted cycloalkenes were obtained from cyclopentene, cyclohexene and cyclo octene. New 1-phenyl-2-phenylazo-substituted alkanes were also obtained from 1-pentene, 1-hexene, cyclopentene and cyclooctene.

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The products and reactivities on the copyrolysis of bromotrifluoromethane and methane, ethane, propane, or hydrogen in the presence of steam at the temperature range of 660-866°C were studied. The copyrolysis was carried out by a flow method under atmospheric pressure using a steam-jet quartz reactor. The major product under the copyrolysis conditions was trifluoromethane in a yield of 65-100%. The reactivities of bromotrifluoromethane on each paraffin were almost equal. The pyrolysis products of the paraffin alone increased with coexistence of bromotrifluoromethane. The minor products bonding with trifluoromethyl group in the copyrolysis of bromotrifluoromethane and ethane or propane were 3, 3, 3-trifluoropropene and 1, 1, 1-trifluoropropane, and the yields were 4-12 and 0.2-9%, respectively. The other hand, the minor product bonding with trifluoromethyl group from the copyrolysis of bromotrifluoromethane and methane was 3, 3, 3-trifluoropropene in yield of 2% or less. Trifluoromethane was obtained nearly 100% in the thermolysis of bromotrifluoromethane and hydrogen at a thermolysis temperature below 760°C.

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A new phenolic sesquiterpenoid, 5-hydroxyisocalamenene [6a] and its m ethyl ether [6b] was synthesized from m-cresol. 4-(2-Methoxy-4-methylphenyl)-4-oxobutyric acid [7] was prepared from m-cresol and succinic anhydride and converted into a dihydronaphthalene [12] via 3, 4-dihydro-5-methoxy-4-isopropyl-7-methyl-1[2H]-naphthalenone [10]. The hydrogenation of [12] gave a tetralin derivative, 5-methoxyisocalamenene [6b] having the stereochemistry of cis-configuration. 5-Hydroxyisocalamenene [6a] was synthesized by the demethylation of [6b] with hydrobromic acid. 6-Methyl-5-(2-methoxy-4-methylphenyl)-2-heptanol [14] prepared from 5-methyl-4-(2-methoxy-4-methylphenyl)hexanoic acid [9] afforded a mixture of [6] and its isomer 8-hydroxycalamenene [5] by the cyclodehydration with hydrobromic acid and p-toluenesulfonic acid. Each of the cyclization products was a diastereomer mixture.
On dehydrogenation of the hydronaphthol [6a] by heating with Pd-C, daucalene [16] and three fused naphthalene derivatives [17], [18], and [19] were yielded. 5-Methoxydaucalene [20b] obtained by aromatization of [12] gave naphthols [20a] and [21a] on treatment with boron tribromide and hydrobromic acid, respectively.

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Thermal decomposition of silicon nitride powder was investigate d along with powder charac teristics such as oxygen content, crystallinity, α-phase content, and specific surface area. The decomposition remarkably promoted above 1450°C to form significant amounts of free silicon after a certain period of the initial process. The oxygen content reduced during the initial process without α/β transformation of silicon nitride. On the contrary, the molar ratio of oxygen to α-silicon nitride was almost constant after the initial process. From the constant molar ratio, the solubility limit of oxygen into α-silicon nitride was estimated to be the composition of Si₃N_3.932-3.9420_0.101-0.086. It was considered that during the initial process the oxygen content reduced by decomposing oxygen-rich surface layers of silicon nitride particles. However, it was impossible to reduce the oxygen content less than the solubility limit by heat treatments. Amorphous powder crystallized to α-phase with poor crystllinity during the initial process. The thermal decomposition easily progressed for powders with poor crystallinity and large specific surface area.

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The ratio of the liquid-phase volumetric transfer coeff icient of ozone to that of oxygen was determined using a bubble column under the conditions that the kinetics of ozone decomposition was negligible in comparison withthe mass-transfer rate of ozone across the gas-water interface. The ratio obtained was 0.84 ± O.03, being independent of the various mixing conditions, the temperature ranging from 283 to 313K, and the ionic strength ranging from O.01 to 1.0. The kinetics of ozone decomposition also indicated that ozone decompose d by an approximately second-order reaction with respect to the ozone concentration in Water. The experiment of volatilizing the ozone dissolved in water to the gas phase enabled continuous monitoring of the ozone concentration, and therefore, the faster and easier determination of the volumetric transfer coefficient. The ratio obtained would be used to estimate readily the absorption rate of ozone into an aqueous solution in a water-treatment facility. If the volumetric transfer coeffient of oxgen is available in the facility, multiplying its value by the ratio of O.84 permits the determination of the volumetric transfer coefficient of ozone.

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Aqueous solutions of chloramine and dichloramine were prepared at pH 10.0 and pH 5.0, respectively, where chloramine and dichloramine were stable for at least 3h. The rate constants for the reactions between the chloramines and a series of compounds were determined at 25°C by the microporous membrane-separation technique. The chloramines separated from the reaction mixture were monitored at 244 nm for chloramine and at 297nm for dichloramine. The reaction were of second order, being of first order in each reactant. The observed second order rate constants for chloramine at pH 6.89 and dichloramine at pH 5.0 ranged from 0.16 (nitrite) to 52.9 (hydroxylamine) M^-1⋅s^-1 and from 0.017 (hydroxylamine) to O.62 (ascorbic acid) M^-1⋅s^-1, respectively.

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A method is proposed for continuous flow determination of chlorine dioxide in water and is applied to the measurements of its chemical reactivity. The method is based on the separation of chlorine dioxide through a microporous PTFE tube and absorbance measurment at 360 nm (λ_max) . The detection limit (S/N=3) was 2.7 × 10^-7M. The response time was 1 min with a microporous PTFE tube of 20 cm in length. The rate constants for the reactions between the chlorine dioxide and a series of compounds were determined at pH 6.89 (25°C). The reaction rates with amino acids and organic acids were low, while those with albumin and humic acid were high.

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The heat of immersion of carbons with different activation was measured in the homologous series of fatty acids(C₃-C₆, C₈) and was compared with that of the same carbons in normal alcohols reported previously. The heat of immersion per unit of the surface area decreased slightly in both acid and alcohol with the progress in the carbon activation. On the contrary the difference in the heat of immersion between the alcohol and the acid increased with the activation of carbon. This result indicates that the polarity of the carbon surface increased with the activation. The decrease in the heat is assumed to be due to the increase in the portion of the carbon surface area which contributes little to the heat of immersion.

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Two stripping methods of analysis of riboflavin were proposed by square w ave polarography in which preconcentration is achieved by the adsorption of riboflavin or its reduced form. The supporting electrolyte used was O.1 M ammonium acetate, the preconcentration potentials were -O.65 V (anodic stripping) and 0 V (cathodic stripping). Preconcentration time was 5 min, and scan rate was 5 mV/s. Square wave amplitude and frequency were 50 mV and 25 Hz, respectively. Sample time was 3 in 10 and temperature was 25°C. Caliblation curves for anodic and cathodic stripping were linear up to 100 nM. The detection limits were 1 nM (anodic stripping) and 0.5 nM (cathodic stripping). Riboflavin in a soft drink was detc mined by the proposed cathodic stripping method.

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Pyrolysis of the phenylhydrazones of aliphatic aldehydes and ketones was investigated at 225-265°C. 3-R₁-4-R₂-5-Methyl-1-phenyipyrazole, 3-R-4-methyl-1-phenylpyrazole, 3-R-5 methyl-1-phenylpyrazole, and 4-methyl- and 4-propyl-1-phenylpyrazole were obtained from PhNHN=C(R₁)CH(R₂)CH₂CH₃, PhNHN=C(R)CH(CH₃)₂, PhNHN=C(R)CH₂CH(CH₃)₂, and PhNHN=CHCH(CH₃)CH₂CH₂CH₃, r espectively. The results indicated that various types of pyrazoles can be synthesized by pyrolysis of phenylhydrazones. N-Alkylideneanilines were also obtained in all cases, except for butanal phenylhydrazone.

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Cationic polyallylamines containing 92-95 mol% of aromatic azo moieties as pendant groups were synthesized. The reversible photochromism and solubility change of poly [N-[p-(phenylazo)benzoyl] allylamine] due to the trans-cis photoconversion of azo moieties were studied. On irradiation at different wavelengths, the above-cited azo-substituted polyallylamine are soluble under ultraviolet light (cis) and precipitate under visible light (trans) in such mixed solvents as 1, 1, 1, 3, 3, 3-hexafluoro-2-propanol (HFIP)-water and HFIP-acetone. The dipole moments of the solvents used are considered to play a role in the reversible solubility change.

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The easy and useful back-extraction method using cop per bis(benzoyltrifluoroacetonate) for measuring the copper(II) complexing capacity (CuCC) was established and applied to the evaluation of the contamination of small river waters in the urban area by human activities.
The change in the CuCC of river waters were coincident with the change in the c oncentration of PO₄^3- and ABS, and good relationships were found between the CuCC and the concentration of PO₄^3- and ABS. From these results, it was concluded that the CuCC reflected the human activities.

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