Plastic thermistors are polymeric thermosensitive materials applied to flexible temperaturesensing wires. These thermistor wires economically constitute fine temperature-control systems with high fail-safety, which have extensively been applied to electric blankets and carpets. These thermistor can be devided into three kinds; an ion-conductive type (I-type), an electron-conductive type (E-type), and a capacitance type (C-type), of which the I-type and the C-type have been used practically and manufactured. The I-type consists of poly (vinyl chloride) compounds doped with organic ammonium perchlorate, and has high temperature sensitivity and excellent thermal stability. On the other hand, the C-type consists of nylon-phenol hybrids doped with a phenol oligomer as the "pseudo-water" in hygroscopic nylon matrices to be less sensitive to humidity. The C-type has excellent thermal stability even under a high DC-component field in addition to the temperature sensitivity and the thermal-fuse function. This paper describes the method of mateiral design and the chemistry of these thermistors mainly, and reviews the technology of the plastic thermistors.

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It was recognized by potentiostatic and galvanostatic methods in the previous paper that the charge and discharge capacity of a silver-silver oxide electrode in KOH solution was increased by the addition of a small amount of manganese(II) chloride. The investigation of this paper was carried out concerning th e case with the addition of a large amount of manganese(II) chloride by the potentiostatic and galvanostatic methods as well as an observation using a scanning electron microscope and an X-ray diffraction. The following results were obtained. ( 1 ) The potential of the initial stage o n a discharge process measured by the galvanostatic method disappeared completely in the solutions with more than 7 x 10^-2 mold of [MnC₁₂.4 H₂O], and the potential of the secondary stage kept the plateau potential throughout the discharge. ( 2 ) The two oxidation-reduction peaks among the four oxidation-reduction peaks on the cyclic voltammograms measured by the potentiostatic method disappeared completely in the solutions with more than 5 x 10^-2 mold of [MnC₁₂.4 H₂O]. ( 3 ) It was observed by the electronmicroscope that the active materials of the electrode grew to be the cohesion under the presence of manganese( II) chloride.

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In order to investigate the effect of magnetic field on electrode reactions with EC (electrodechemical reaction) and ECE (elctrode-chemical-electrode reaction) processes, the electrochemistry of 1, 4-benzoquinone (Q) and oxygen molecule in aprotic solvents was studied with cyclic voltammetry (CV) in steady high magnetic fields up to 15 T. A new anodic peak was observed above 6 T at 1.2 V (vs. Ag/AgCl) in the CV curves of Q in N, N-dimethylformamide (DMF). For the electrode reaction of oxygen in the presence of diethyl malonate (DEM) in DMF, the rate-determining step was found to shift from the diffusion step into the chemical reaction step of O2^- and DEM, with increasing magnetic fields. These results were explained in connection with the magnetohydrodynamic effect.

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Partial hydrogenation of benzene-d6 was carried out with Ru catalyst, promo tor and H₂O system. The reaction scheme, especially for the process of addition of hydrogen, was clarified by analysis of remaining D value in the hydrogenated products. On the Ru catalyst surface, in addition to hydrogenation reaction, a notable reaction also occurrs such as C -DH exchange reaction between adsorbed substrates, especially olefin and adsorbed hydrogen generated from H₂ and H₂0. The latter reaction was emphatically observed within the production route of cyclohexene in Zn-promoted catalyst system. The new production route of cyclohexane was clarified. This route is explained as the hydrogenation of cyclohexene with the adsorbed hydrogen regenerated by dehydrogenation of cyclohexene on the catalyst surface.
Selectivity of cyclohexene was very increased by Zn-promoted catalyst system. This effect may be attributed to that; ( 1) on the catalyst surface, Z n compound raises the stability of hydrogenated intermediates, therefore further hydrogenation of the intermediates to cyclohexane is restrained, and ( 2 ) Zn compound hinders readsorption of produced cyclohexene to the catalyst surface, therefore hydrogenation of cyclohexene to cyclohexane is also restrained. Par tial Hydrogenation of Benzen. I.

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The liquid phase hydrogenation of crotonaldehyde has been i nvestigated with silver and silver-manganese catalysts supported on alumina? aluminium phosphate. The relationship between catalytic activity and selectivity to trans-2-buten-1-ol was examined. Catalysts were prepared from metal nitrates by the impregnation method. Reaction was carried out at 130-210°C and 10-70 atm of hydrogen with a 10 vol% crotonaldehyde-hexane solution and 1.0 g of a catalyst in a 300 ml autoclave. With an increase in the P/A1 atomic ratio in the catalyst support, dehydrogenation of 2buten-1-ol to crotonaldehyde becomes prominent, leading to a decrease in apparent conversion. The selectivity is kept constant in the range of P/A1-=0--0.8, and decrease at P/A1=1.0where a crystalline Ag₃PO₄ is formed. Manganese added to silver catalyst as a promoter was found to increase both activity and selectivity of the catalyst. When the atomic ratio of manganese to silver was 1.5 or above, the yield of 2-buten-1-ol was 70.5 mol%, whereas it is only 36.6 mol% over the catalyst without manganese addition.

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The effects of crystal catalyzer on the transformation of calci um sulfate dihydrate (CaSO₄.2H₂O) to α-hemihydrate has been studied by using high-pressure differential thermal analysis (HPDTA) under various nitrogen pressure up to 5 M Pa. The intermediates formed at desired temperatures in HPDTA were identified by differential scanning calorimetory under the selfgenerated atmosphere and were also observed by a scanning electron microscope.
HPDTA curves were influenced by the species and amount of the catalyzer; the way of its addition, the particle size of original dihydrate and the nitrogen pressure. The peak temperature due to the transformation to α-form was shifted to higher temperatures with increase in the effect of the catalyzers. The addition of the catalyzer affected not only the solubility of dihydrate in solvent, but the crystallization rate of hemihydrate. The shape and temperature of dehydration peak of hemihydrate were dependent on the character of hemihydrate formed in HPDTA. The appearance of a small endothermic peak at about 200°C above 3 MPa showed that the transformation to anhydrate took place easily in water under the pressurized atmosphere.
The SEM micr ographs of hemihydrate and anhydrate obtained indicated characteristic shapes depending on the species of the catalyzer and the way of its addition.

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The separation of protochlorophylls from the inner seed coats of pumpkin (C, maxima)were examined by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). The chromatogram of protochlorophylls were obtained as one spot (R_t=0.54) by cellulose-TLC [Fig.1] but in the case of ODS-TLC [Fig.1 ( 2 )] and/or ODS-column HPLC [Fig.3] the chromatograms were obtained three peaks (Rt=9.35, 10.26and 12.35 min). The absorption spectra of these three protochlorophylls were completely same in visible region [Fig, 2] These pigments were identified to be 4-vinyl-protochlorophyll a. They were named 4-vinyl-protochlorophyll a₁, a₂, and a₃, respectively. The structure of three species of 4-vinyl-protochlorophylls a were identified by fast atom bombardment mass spectrometry (FAB/MS). FAB/MS spectra of these pigments were shown in Fig.4. Quasi molecular ions appeared at m/z=887, 885 and 883, respectively. Common fragments ions cleavaged at esterifing C₂₀ isoprenoid alcohols of a1, a₂, and a₃, observed at m/z.611, 551and 479. The chemical structure of these quasi molecular ions and fragments ions were shown in Fig.5. The results of these analysis suggested that three 4-vinyl-protochlorophylls a from the inner seed coats of pumpkin were identified to be al; 4-vinyl-protochlorophyll a-THGG (tetrahydrogeranylgeraniol), a₂, ; 4-vinyl-protochlorophyll a-DHGG (dihydrogeranylgeraniol)and a₃, ; 4-vinyl-protochlorophyll a-GG (geranylgeraniol).

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The extraction behavior of indium(III) ion from aqueous oxalic acid solution (40.0±0.2°C)with trioctylamine (R₃, N) in benzene have been studied. Extracted indium (III) species was isolated from the extract using preparative gel permeation chromatography. The compositional formulas of the isolated indium(III) species is estimated to be (R₃NH)₃1n(C₂O₄)₃ on the basis of the data of chemical and elemental analyses and infrared spectrum of this compound. Molecular weight of extracted indium(III). species was measured with vapor pressure osmometric method (VPO). Molecular weight estimated by extrapolation to infinitely dilute solution is in agreement with formula weight of the extracted indium (III) species.
Association behavior of (R₃NH)HC₂O₄ in benzene which appears to plays an important role in the extraction of metal ions from aqueous oxalic acid solution have been investigated. It can be seen from the results of molecular weight measurement of the (R₃NH)HC₂O₄ with VPO that this species in benzene exists predominantly as monomer and dimer. Values of formation constant (K₂) of (R₃NH)HC₂O₄ dimer at 30°C, 40°C and 50°C are found to be 35.0+0.3, 24.0+0.5 and 16.0±0.3, respectively. Moreover, from an approximately linear relationship between the log K₂ and 1/T, heat of formation of (R₃NH)HC₂O₄ dimer is estimated to be about -31.8 kJ.mo-1 which corresponds to the heat of hydrogen bonding. Dependence of distribution ratio of indium(III) species on concentration of (R₃NH )HC₂O₄dimer also has been discussed.

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Investigations of the pK_a's (acidities and basicities) of, organic compounds have played an i Tmhpeo rtraenlta tioronles hitpo btheet wuenedner s ptaKndai'nsg ando f ththee fraecatcotirvsi tyo r atnhde tihned ipcreosp edretireisv eodf forrogman ict h ec ommpooluencdusla. r structures of compounds have been extensivly studied. Correlation of Hammetts' substituents constants and pK_a's is a good example. Very recently, a priori pK_a calculation using novel th eoretical procedures have been done. However, the compounds calculated were relatively small.
In the present work, correlation of pK_a's of organic compounds and the indices derived from, semi-empirical calculation that will give higher correlation coefficients wer e investigated. C alculation methods employed were PPP (Pariser-Parr-Pople) method, CNDO/2 method and E xt-HMO method. In MO approaches, pi- electron density Q_x (=I₁ ) on atom X on which proton (H⁺) is transferred, or ionization potential of atom X, Q_p(XX | pp) (=I₂) that is taken into account the effect of other atoms (or Q_p/r_xp (=I₂')) are sometimes employed. However, the single index is not necessarily enough. New index(I) was made as a linear combination of two indices, I₁ and 1₂ (or I₂', i. e., I=lI₁+m'I₂') (l+|m|=1; m= -1 -1). Then, parameters l and m (weights of I₁ and I ₂) were varied so as the correlation coefficient of pK_a's vs. I to be maximized. After aimed parameters were obtained, I_opt vs. pK_a's were plotted. The method was named as Maximum Correlation Coefficient I Method. Va1ues of 1 thus obtained for aza aromatic amines (aminopyridines, aminoqu inolines, aminoacridines) were in the range of 1=0.9-0.92, and l=0.90-0.93 whe n purines were included. For the ratio of I₂ and I, ₁(I₂/I₁)=3-5, and (I₂'/I₁) =0.12-0.22 were obtained. The ratios of second term and first term of new indices in optimum condition were as follows (|m|1₂11.1₁)=0.33-0.56 (for 1=0.9), and (| m'| . I₂'/l'. I₁. ) = 0.28--0.51 (for l'=0.3 ).,

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The indirect electroreduction of acetophenones 1 a-1 g in the presence of catalyti c amounts of Sb(III) chloride led to formation of corresponding monohydric alcohols 2 a -2 g which were difficult to be prepared by the direct electroreduction. The electrolysis conditions were found tHoC 1h-aEvte0 H-an -BsturoOnHg effemcet dioan (t5h0e myl)i eldusn deorf 2h ae- 2f ogll. o wiAn g 98c%on dyitiieoldn s of; c2a tah odwea s: olebatda, i needl ectirni citayq. passed: 4 F/mol, constant current density: -3.7 mA^-2, 1 a: 8.3 mmol, SbC13: 0.2 mol% 1al c '. Wh en an amount of SbC13 increased, the advantages of this method were also observed for the selective reduction of 1 g which contains two potentially reducible functional groups and a corresponding 1-(4-iodophenyl)ethanol was obtained without cleavage of carbon -halogen bond. When the analogous electrolysis were conducted to the other compounds having various functional groups, only benzaldehyde was converted smoothly to benzyl alcohol with high yield. A possible reduction mechanism which accounts for the formation of SbH₃, through the reduction of Sb deposited on the electrode surface by active hydrogen atom is illustrated in Scheme 2.

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The configuration of 3-[(8 Z, 11 Z)-8, 11, 14- and (8 Z, 11 E, 13 E)-8, 11, 13-pentadecatrienyl]catechol, components of sap in Japanese Lac, Rhus vernicifera, has been confirmed by the synthesis of their dimethyl ethers 2 and 4. In the synthetic route to the target compounds 2 and 4, cis-double bond at the 8-position in the side chain was constructed by a Wittig reaction between the aldehyde 10 and the ylide derived from the heptadienylphosphonium salt 15 and 18, respectively (Fig.2). The aldehyde 10 was synthesized from veratrole by alkylation as shown in Fig.3. The heptadienylphosphonium salts 15, 18 were easily synthesized from 3-butyn-1-ol and bromocyclopropane as shown in Figs.4 and 5, respectively.

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The conversion process from polydimethylsilane to polycarbosilane in the presence of a small amount of BBr3, polyborodiphenylsiloxane (PBDS), B(OC₄H₉)₃ or B(OH)₃ was investigated on the basis of the reaction of the low molecular weight organosilicon compounds (LMOS), which were the intermediates at the initial stage during this conversion, with these boric compounds at 200--340°C. The changes in unit structures of the intermediates and products during the polymerization, which consists of a decomposition reaction, a rearrangement reaction and a propagation reaction, were examined by the measurement of IR spectra, UV spectra, and GPC. The boric compoumds played a role in accelerating the propagation reaction by dehydrogenation between Si-H bonds in LMOS among above three reactions. In order to clarify the role of these boric compounds in the propagation reaction, the relationship between these reactivities and the acid strength of these boric compounds, was studied. The order of the aforesaid accelerating effect of these boric compounds, BBr₃, PBDS, B(OC₄H₉)₃ and B(OH)₃, on the propagation reaction agreed with that of the acid str ength of these boric compounds. From the results of thermogravimetric analysis of the produced polymers, both the increase in the molecular weight due to the propagation reaction and the formation of Si-CH₂-Si bonds by the rearrangement reaction of silicon radicals, which were formed by the decomposition reaction of LMOS, at above 300°C were found to be important for obtaining the convertible organosilicon polymer into pyrolysis products in a high yield. BBr₃ was undesirable for obtaining the convertible organosilicon polymer into the inorganic material in a high yield, because BBr₃ with the highest acid strength of these boric compounds, accelerated the dehydrogenation of Si-H bonds even at 200°C and then hindered the formation of Si-CH₂-Si bonds by the rearrangement reaction at above 300°C. B(OC₄H₉)₃and B(OH)₃, which showed less accelerating effect on the propagation reaction than BBr₃and PBDS, were also ascertained to be disadvantageous for producing the suitable organosilicon polymer to get the inorganic material. PBDS with -0.85<H <02.80 of the acid strength was the much more predominant accelerator than another boric compounds for the production of the convertible organosilicon polymer into the inorganic material in a high yield, because of the moderate accelerating effect on the propagation reaction and no hindrance for the formation of Si-CH₂-Si bonds.

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A variety of 2-arylthio-N-alkylmaleimides were prepared from 2-arylthio-N-alkylsuccinimides. We have screened for antimicrobial activity of these compounds, and examined an effect of substituents of benzene ring and N-alkylchains against antimicrobial activity. Almost all these compounds showed good inhibitory effect against B. substilis and yeast. Especially, 2-phenylthio N-lower alkyl-maleimides showed an excellent activity against Gram-positive bacteria, fungi and yeasts. The Studies on the Preparation an d Antimicrobial Activity of Maleimide Compounds. iv.

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Excellent properties of the polyallylamine-poly (vinyl alcohol ) (PAAm-PVA) matrix available in the ISFET (Ion-sensitive field effect transistor) biosensor were found. By coating the PAAm-PVA including high density enzyme onto the gate of the N channel deflection type field effect transistor, the enzyme was immobilized and the ISFET biosensor was fabricated.
Degree of immobilization, swelling and, residual membrane of the immobilized GOD showed the enough toughness and good immobilization. It was found that due to the growth of the microcracks on the surface, the immobilized enzyme membrane become blushing by treatment of glutaraldehyde. The membrane never stripped from the gate of the ISFET dipped in aqueous solution for a week. This means it is adhesive enough to use in the ISFET.
To measure the effect of PAAm-PVA matrix for glucose oxidase (GOD), apparent activity of the GOD membrane was determined by oxygene electrode. The result implies that the matrix is as good enzyme matrix as silk fibroin, which is the excellent immobilized matrix.
The urea, the alcohol or hypoxanthine sensor, were obtained by coating the PAAm -PVA incluiding the urease, the alcohol dehydrogenase and β-NAD⁺ membrane, or the xanthine oxidase membrane, respectively. The urea sensor thus fabricated shows the sensitivity of 60 mV/mM from 0.1 to 1 mM, which is 20 times higher than published data. The alcohol sensor shows the sensitivity of 2.3 mV/M up to several decade percent, and the hypoxanthine sensor shows that of 22 mV/mM from 0.05 to 3 mM.
PAAm-PVA enzyme membrane reported here can immobilize the high density enzyme, and it's activity and durability were enough. This means the enzyme membrane is most suitable for the ISFET biosensor.

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Amphiphilic phosphobetaine "Alkyl 2-Hydroxy-3-tri methylammoniopropyl Phosphates"(Alkyl; C₁₂, C ₁₄, C HOC ₁₈, abbreviated as C_n-AHTMAP) were synthesized by th e reaction of potassium monoalkyl dihydrogenphosphate (C_n-MAP-K) and 2, 3-epoxypropy1trimethy1ammonium chloride (EPMAC). The opening of the epoxy ring of EPMAC was the selective -fission. (Scheme 3) When r≥2 (r; molar ratio of EPMAC/C_n-MAP-K), C_n-AHβTMAP was quantitatively obtained. (Fig.1)Electrodialysis was effectively ap plied for the purification of watersoluble C_n-AHTMAP from the aqueous reaction mixture. (Fig.2)On the other hand, by the equimolar re action of dialkyl monohydrogenphosphate (DAP), MAP or phosphoric acid (PA) with EPMAC, the salt of the anion of DAP, MAP or PA and 2-Hydroxy-3-chloropropyltrimethylammonium (HCPA) cation was produced and C_nAHTMAP was not obtained. (Scheme 2, Fig.1)Some physicochemical properties of C_n-AHT MAP (critical micelle concentration (cmc), surface tension, free energy of micellization, area per molecule, foaming power, and foam stability) concerning surface-activity were measured. (Tables 1, 2, Fig.3) The surface tensions at cmc (γcmc)o f C₁₂, C₁₄a nd C₁₆-AHTMAP aqueous solutions were not affected by alkyl chain length (38 mN/m). C₁₂a nd C₁₄-AHTMA P showed good foaming power and foaming stability. TheReaction of Epoxy-compound with Phosphate.II

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Sodium dodecyl 2-hydroxy-3-chloropropy1 phosphate (C₁₂-AHCP-Na) was synthesized by the reaction of sodium dodecyl hydrogenphosphate (C₁₂-MAP) and 1, 2-epo. xy-3-chloropropane. (Fig.1, Scheme 1, A), Sodium dodecyl 2, 3-epoxypropyl phosphate (C₁₂-AGP-Na) was obtained quantitatively by the treatment of C₁₂-AHCP-Na with equivalent amount of NaOH. '(Scheme 1, B) C₁₂-AGP-Na is an amphiphilic Phosphoric acid ester containing a reactive ep oxyring, which can react with various active hydrogen compounds. The reactions of C₁₂-AGP-Na with some am ino acids (glycine, N-methylglycine and Lcysteine)were studied, and new amphiphilic amino acid derivatives of MAP 1, 2 and 3 were obtained. (Scheme 2) In, the Teact, ion of C₁₂-A. GP-Na with glycipe in aqueous solution, the hydrolysis of C₁₂-AGP-Na, which gave sodium dodecyl- glyceryl phosphate (C₁₂-AGCP-Na), was unavoidable, but with the equirnolar amount of L-cysteine in aqueous solu tion, L-cysteine derivatives of MAP were obtained quantitatively.
By the analysis of the NMR spectra of 3 it was suggested that th e, ring opening of the epoxide of C₁₂-AGP-Na was the selective β-fission by the -SH group of L-cysteine. From the studies on the reactivity of C₁₂-AGP with HS-CH₂CH₂-OH, H₂N-CH₂-CH₂-OH, and OH-CH₂C11₂-OH in the dilute borate buffer solution (pH=9.5), the order of reactivity of tthe. active hydrogen groups for the epoxide of C₁₂-AGP-Na was -SH>-NH₂>-OH (-OH had no reactivity). The m odification of BSA (Bovine Serum Albumin) with C₁₂-AGP-Na in the dilute borate buffer solution (pH=9.5) was studied. From the SDS-polyacrylarnide gel electrophoresis analysis (Fig.2), ³¹P-NMR spectrum analysis, and the free -NH₂ group determination, it was found that BSA was effectively modified with C₁₂-AGP-Na and this suggests that AGP can be applicable to protein and peptide for as a new type of modifier. The Reaction of Epoxy-compoundw itht Phosphate. III.

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Poly(vinyl chloride) (PVC) powder consisting of 0.45 or 1.52 μm primary particles, was granulated by tumbling with a water medium. The following relationship was obtained between the feed rate (W_p) of fine grain PVC (average size: 3 μm), the feed rate (W₈) of PVC seed (average size r₁; μm) and the size (r₂; μm) of the granulate PVC.
r₂={(W_p/W₈) α +1}1/3r₁, [α is 1.21 when r₁, is 290 μm]
The granulate PVC, the moisture content of which is 3 5-37 wt%, was heat-treated at a constant temperature for 1 h to get spherical PVC. The following equations were set up between the physical properties of the spherical PVC and the heat treatment temperature (T°C).
Pore volume (cm^-3 g ^-1) = - 9.0 8 × 10^-3 T +1.51 (107≤ T≤150)
Specific surface area (cm². g^-1) = -1.08x 10^-1 T +15.1 ( 9 5 ≤ T≤136)
Bulk density (g. cm^-3) =3.70 × 10^-3 T+0.118 (107≤T≤150)
Crushing strength (g/one particle) =4.32 x 10 T - 4 9 00 (125 ≤T≤150)
A chelate resin containing dithiocarbamic acid moiety was synth esized by the reaction of the spherical PVC with ethylenediamine to yield aminated PVC, and by the reaction of the aminated PVC with carbon disulfide. The ratio of specific surface area (S_1.52/S_0.45) and the ratio of mercury adsorption quantity (Q_1.52/Q_0.45) on the chelate resin, where the subscripts are the average size of primary particles of the chelate resin, were both 0.30. The chelate resin consisting of primary particles of 0.45 μm size showed excellent mercury adsorption ability.

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It was observed that Methylene Blue was dimerized at the cancentration of 10^-5 mo1.dm^-3in water (Fig.1). There relation between inctination angle α and center-center distance of was shown. The photobleaching of Methylene Blue was stimulated at Iow concentration of detergent and inhibited at high concentration (Fig.3). It was found that the shorter the chain Iength of anionic detergent exhibits larger effect of inhibition (Fig.4).

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The monthyl 1 h maximum concentrations were analyzed for SO₂, NO_x(NO, NO₂), NMHC, O_x and CH₄ from 1979.4 to 1989.3 and compared with monthly mean concentrations. For CH₄, yearly mean concentrations were also analyzed. All the data used were the air monitoring data which had been continuously measured at an urban (Yokohama city) and a suburban (Odawara city) monitoring station in Kanagawa Prefecture. The coentration of each air pollutant mentioned aboves howed a large monthly variation; especially for SO2, NOxa nd NMHC high concentrations were measured in winter at theurbanstation, and for O_x high concentrations were. nneasure tnsummer at thesuburban station.Foryearlyvariation, maximum concent ratio of SO₂, NMH Candqshowed a trendof sma11 decrease, but NO_x did not show obvious decrease. CH₄conc et rations also showed a large monthly variation in theurbanstation. Yearly mean concentration of CH₄was 1.85 PPm at the urban station and 1.80PPm at the suburban stationin 1988 fiscalyear. At both the stations, CH₄ showed a trend of small yearly increase.

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