bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydrates of Organic Compounds. XII. Intercalation of Methyl and Ethyl Alcohols within the Clathrate-Like Hydrates of Tetrabutylammonium Fluoride and of Tetrabutylammonium Propionate
Authors: Nakayama Haruo , Tsunakawa Kiyoshi , Kan\={o} Mizue , Matsui Hiroshi 
Published: July 2006

Abstract
The amount of either methyl or ethyl alcohol intercalated within clathrate-like hydrates of tetrabutylammonium fluoride and of tetrabutylammonium propionate has been determined using 14C-labeled alcohols. It was found that (1) methyl alcohol could be intercalated within the tetrabutylammonium fluoride hydrate but not within the tetrabutylammonium propionate hydrate; (2) ethyl alcohol could be intercalated within both the tetrabutylammonium fluoride and tetrabutylammonium propionate hydrates; and (3) the amount of the alcohol intercalated increased with increasing concentration of alcohol in the initial solutions. These results were interpreted by taking into consideration the states of vacant pentagonal dodecahedra formed by hydrogen-bonded water networks.
The Reaction of N(24S3⁄2) with Hydrogen Halides and Deuterium Iodide
Authors: Umemoto Hironobu , Uchida Teruo , Tsunashima Shigeru , Sato Shin 
Published: July 2006

Abstract
The bimolecular rate constants for the reactions of ground state atomic nitrogen with hydrogen halides and deuterium iodide were measured by employing a pulse radiolysis-resonance absorption technique. As for the reactions of hydrogen iodide and deuterium iodide, the temperature dependence was also measured; it was found that the rate constants were well expressed by the following Arrhenius expressions: k(N+HI)=(3.6±0.6)×105 exp[−(1530±50)⁄T]; k(N+DI)=(1.0±0.4)×105 exp[−(1460±130)⁄T], in units of m3 mol−1 s−1. The preexponential factors for these reactions are much smaller than the semiempirically calculated ones. These small preexponential factors suggest that these reactions proceed non-adiabatically. The rate constants for hydrogen bromide and hydrogen chloride were found to be very small.
Electrochemical and Spectroelectrochemical Speciation of [5-phenyl-10,15,20-tris(4-sulfonatophenyl)porphinato]iron in Aqueous Solution
Authors: Arifuku Fumihiro , Nishino Rika , Ujimoto Kikujiro , Kurihara Hirondo 
Published: July 2006

Abstract
The equilibria among the species of [5-phenyl-10,15,20-tris(4-sulfonatophenyl)porphinato]iron (Fe–TPPS3) ion in aqueous solution and the redox reactions of the central metal were investigated by electrochemical and spectro-electrochemical methods. In the range of pH 3–12.5, the species formed by the reduction of Fe(III)–TPPS3 in solution was identified as the monomeric Fe(II)–TPPS3, while Fe(III)–TPPS3 exists in both monomeric and dimeric species in equilibrium. The monomeric Fe(III)–TPPS3 was demetallated at pH below 3 in the course of reduction of the Fe(III)–TPPS3 solution. The μ-oxo-dimer of Fe(III)–TPPS3 in highly basic solution was reversibly reduced to Fe(II)–TPPS3 and subsequently the monomeric Fe(I)–TPPS3. The formation of the stacking-type dimer of Fe(III)–TPPS3, significantly depending on the concentration of Fe(III)–TPPS3, was presumed to have a pH below 6.
Regio- and Stereoselectivity of the Intramolecular C–H Insertion by Cyclopropylidenes Bearing a Remote Oxido Substituent
Authors: Harada Toshiro , Yamaura Yasunari , Oku Akira 
Published: July 2006

Abstract
(ω-Oxidoalkyl)cyclopropylidenes generated from (2,2-dibromo-1-methylcyclopropyl)-CH2–X–(CH2)n–OH (X=CH2 or O, n=1, 2) by the reaction with methyllithium underwent a regioselective intramolecular insertion into the C–H bond at the δ position to the carbenic carbon. The activation effect of the oxido substituent on the reactivity of C–H bonds is discussed on the basis of (1) the ratio of the insertion products to the rearrangement product allenyl alcohol, and (2) the endo stereoselectivity of the present insertion reactions.
Chemo-Selectivity of Group-VIII Metal Catalysts in Hydrogenation of Nonconjugated Enones
Authors: Ishiyama Jun-ichi , Maeda Satoshi , Takahashi Kazuhiro , Senda Yasuhisa , Imaizumi Shin 
Published: July 2006

Abstract
The chemo-selectivity of group-VIII metal catalysts has been examined in the hydrogenation of nonconjugated enones at ambient temperature under an atmospheric pressure of hydrogen. A cobalt catalyst gave high yields of unsaturated alcohols from trialkylated olefinic ketones. Osmium showed the highest selectivity among platinum metal catalysts for the reduction of the carbonyl bond in the hydrogenation of trialkylated olefinic ketones. The hydrogenation of mono- and dialkylated olefinic ketone ordinarily proceeded with a preferential saturation of the olefinic function, regardless of the catalyst. The hydrogenation of 4-methylene- and 4-ethylidenecyclohexanone was accompanied by the formation of diethyl acetals over ruthenium, rhodium, and palladium black catalysts in an ethanol solvent. The acetals were not detected in the hydrogenation of the other enones and over the other catalysts. In addition, the chemoselectivity on the hydrogenation of acyclic enones was examined over nickel and cobalt catalysts treated with small amounts of alkali and carbon monoxide. The amount of unsaturated alcohols increased when the catalyst was treated with alkali in the case of di- and trialkylated olefinic ketones, whereas the characteristics of cobalt, which selectively reduces the ketonic function in trialkylated olefinic ketones, were completely missing when cobalt was treated with carbon monoxide.
Construction of an Optically Active 7-Oxabicyclo[4.3.0]non-4-en-3-one Skeleton from d-Glucose, and Its Transformation to Some Pseudo-Hexopyranoses
Authors: Tadano Kin-ichi , Ueno Yoshihide , Fukabori Chiyoko , Hotta Yukinori , Suami Tetsuo 
Published: July 2006

Abstract
A versatile chiral compound, (1R,6R,8R,9R)-8,9-isopropylidenedioxy-7-oxabicyclo[4.3.0]non-4-en-3-one (6), was efficiently synthesized from d-glucose. The synthesis featured an intramolecular aldol cyclization of 3-C-acetylmethyl-3-deoxy-1,2-O-isopropylidene-α-d-ribo-pentodialdo-1,4-furanose, which was readily derivatized from the known Wittig adducts of 1,2:5,6-di-O-isopropylidene-α-d-ribo-hexofuranos-3-ulose. The utility of this highly functionalized chiral synthon 6 was embodied by conversion to four optically active pseudosugars, these are pentaacetyl derivatives of pseudo-α-l-altropyranose, pseudo-β-d-glucopyranose, pseudo-2-amino-2-deoxy-β-l-altropyranose, and pseudo-2-amino-2-deoxy-α-d-glucopyranose (a derivative of pseudoglucosamine). The transformation of 6 to the pseudo sugars involved 1) a stereospecific epoxidation of the double bond in 6 providing (1R,4S,5S,6S,8R,9R)-4,5-epoxy-8,9-isopropylidenedioxy-7-oxabicyclo[4.3.0]nonan-3-one (8), and 2) an exclusive diaxial ring opening of the β-epoxy alcohols, which were derived from 8, providing (1R,3R,4S,5S,6S,8R,9R)-8,9-isopropylidenedioxy-7-oxabicyclo[4.3.0]nonane-3,4,5-triol (11) or (1R,3S,4S,5R,6S,8R,9R)-4-azido-8,9-isopropylidenedioxy-7-oxabicyclo[4.3.0]nonane-3,5-diol. Treatment of (1R,2S,3S,4S,5R)-3,4,5-tris(benzyloxy)-2-hydroxycyclohexanecarbaldehyde, which was derived from 11, with methanesulfonyl chloride, and successive sodium borohydride reduction provided (3S,4S,5R)-3,4,5-tris(benzyloxy)-1-cyclohexene-1-methanol (19). Hydroboration of 19 proceeded from the less hindered side stereoselectively.
Reaction of Olefins with α-Cyanoacetamide in the Presence of Manganese(III) Acetate
Authors: Sato Hidehiko , Nishino Hiroshi , Kurosawa Kazu 
Published: July 2006

Abstract
2-Butenamides and 2-buten-4-olides are formed by the reaction of phenyl or 4-chlorophenyl-substituted olefins with α-cyanoacetamide in the presence of manganese(III) acetate. On the other hand, aryl substituted olefins having electron-donating groups are oxidized under similar reaction conditions to give 1,5-dihydro-2H-pyrrol-2-ones and 3-ethenyl-2-pyrrolidones. All these reactions also produce glycols or ketones which are given by the direct oxidation of these olefins with manganese(III) acetate. The question whether an intermediate carbocation in the oxidation process cyclized on an oxygen or a nitrogen atom can be explained by the hard and soft acids and bases (HSAB) concept. A possible mechanism for the formation of 2-butenamides and 2-buten-4-olides is proposed.
Synthesis and Properties of Chiral Macrobicyclic and Macrotricyclic Cryptands Containing the trans-Tetrahydrofuran-2,5-diylbis(methylene) Subunit as the Chiral Center
Authors: Naemura Koichiro , Kanda Yuji , Iwasaka Hiroshi , Chikamatsu Hiroaki 
Published: July 2006

Abstract
The macrobicyclic and macrotricyclic cryptands containing the trans-tetrahydrofuran-2,5-diylbis(methylene) molecular framework as the chiral subunit were prepared in optically active forms. The enantiomer recognition property of the macrotricyclic tetracarboxamide (+)-6 in transport of enantiomeric molecules was examined, and the cation-binding abilities of the macrotricyclic and macrobicyclic amines 7, 10, and 13 were also investigated.
In-beam EIMS and Molecular SIMS of Quaternary Ammonium Chlorides of Benzylamine Derivatives
Authors: Shida Yasuo , Tsujimoto Kazuo , Ikeda Takashi , Ohashi Mamoru 
Published: July 2006

Abstract
The in-beam EIMS and SIMS of three quaternary ammonium chlorides of benzylamine derivatives have been examined, and their fragmentation processes have been clarified by means of the B⁄E costant and B2⁄E constant linked scanning techniques. The B⁄E constant linked scan of the benzyltrimethylammonium ion (m⁄z 150) in the in-beam EIMS indicated a fragment ion at m⁄z 126 as a daughter ion. A substitution reaction between the m⁄z 150 ion and a chlorine atom in the first field free region is proposed. The characteristics of SIMS of those compounds were demonstrated in comparison with those of EIMS and the fragmentation processes of the salts upon Xe+ bombardment were established based on the linked scanning techniques.
1,4-Dihydropyrrolo[3,2-b]pyrrole: The Electronic Structure Elucidated by Photoelectron Spectroscopy
Authors: Tanaka Shoji , Kumagai Tsutomu , Mukai Toshio , Kobayashi Tsunetoshi 
Published: July 2006

Abstract
The electronic structures of 1,4-dihydropyrrolo[3,2-b]pyrrole and some of its alkyl derivatives were studied by means of He(I) photoelectron spectroscopy combined with the MNDO calculation and a first-order perturbation theoretical method. The first five bands of the parent pyrrolopyrrole are assigned, from the top, to the π5(au), π4(au), π3(bg), π2(bg), and σ(ag) bands respectively. The MO model, which explains well the spectral data, indicates that the nitrogen lone-pair electrons are mainly delocalized in the π4, π2, and π1 orbitals. The ionization potentials of the HOMO levels of these compounds, which are characterized by the large pz contributions from the α-carbons, are the lowest among the hitherto known π-electron-excessive heteroaromatic compounds. 1,4-Dihydropyrrolo[3,2-b]pyrrole is concluded to be the system with the most efficient π-electron-donating ability among 10π-electron systems.
The Nucleophilic Reaction upon Electron-Deficient Pyridone Derivatives. VIII. Novel Fragmentation of 3,5-Dinitro-2-pyridone by Primary Amine
Authors: Tohda Yasuo , Ariga Masahiro , Kawashima Toshihide , Matsumura Eizo 
Published: July 2006

Abstract
Fragmentation of 3,5-dinitro-2-pyridone (1) by primary amine gave nitroacetamide (2) and nitromalonaldehyde diimine. In the case of N-methyl derivative (1c), the reaction was completely suppressed by the product 2 to give an anionic σ-adduct of 1c with 2. The mechanism of the reaction was discussed.
Stereoselective Synthesis of Anomers of 5-Substituted 2′-Deoxyuridines
Authors: Aoyama Hajime 
Published: July 2006

Abstract
The substitution reaction of 5-substituted 2,4-bis(trimethylsilyloxy)pyrimidines with 3,5-bis(O-p-chlorobenzoyl)-2-deoxy-α-d-ribofuranosyl chloride was investigated. In the presence of p-nitrophenol, β anomers were formed stereoselectively, whereas the addition of organic bases brought forth stereoselective formation of α anomers. Stereoselectivity of the reaction depends on the substituents at 5-position of disilylpyrimidines, additives, and the concentration of each reagent. The α and β anomers of 5-substituted 2′-deoxy-uridines were synthesized through the deacylation of α and β anomers of 5-substituted 3′,5′-di-O-(p-chlorobenzoyl)-2′-deoxyuridines.
The Reactions of Tropone Tosylhydrazone Sodium Salt with Acetylene Derivatives Possessing Electron-Withdrawing Groups: A Novel Method of Synthesis of 1H-1,2-Benzodiazepine Derivatives
Authors: Saito Katsuhiro 
Published: July 2006

Abstract
Reactions of tropone tosylhydrazone sodium salt with dimethyl and diethyl acetylenedicarboxylate gave dimethyl and diethyl 1H-1,2-benzodiazepin-3,4-dicarboxylate, respectively. The same reactions, but using ethyl acetylenecarboxylate and 3-butyn-2-one, afforded ethyl 1H-1,2-benzodiazepin-4-carboxylate and 4-acetyl-1H-1,2-benzodiazepine, respectively, accompanied by 8-azaheptafulvene derivatives derived from the sodium salt and the acetylene derivatives, and p-toluenesulfinic esters formed from p-toluenesulfinic acid and the acetylene derivatives. Reactions of the sodium salt with ethyl 2-butynoate gave the corresponding sulfinic ester but afforded no diazepine derivative.
A New Synthesis of 3-Amino-2-alkenoates. Novel Synthetic Route to Amino Sugars N-Benzoyl-l-daunosamine and -l-acosamine
Authors: Hiyama Tamejiro , Kobayashi Kazuhiro , Nishide Kiyoharu 
Published: July 2006

Abstract
Alkanoate esters are found to couple with various nitriles to give (Z)-3-amino-2-alkenoates in good yields with the aid of a magnesium amide prepared by the reaction of ethylmagnesium bromide and diisopropylamine. The C–C bond forming reaction was applied to (2S,3S)-2,3-(cyclohexylidenedioxy)butanenitrile and the resulting adduct was successfully converted into N-benzoyl-l-daunosamine in 41% overall yield through a sequence of functional group manipulation; acetylation, hydrogenation, hydrolysis and benzoylation, lactonization and finally reduction. By the similar process, (2R,3S)-2,3-(cyclohexylidenedioxy)butanenitrile was transformed to N-benzoyl-l-acosamine in 25% overall yield.
An Enantiospecific Synthesis of the C-21–C-37 Segment of the Aglycon of Amphotericin B
Authors: Kinoshita Mitsuhiro , Takami Hitoshi , Taniguchi Masato , Tamai Tetsuro 
Published: July 2006

Abstract
3-Deoxy-1,2-O-isopropylidene-3-C-methyl-α-d-allofuranose was stereoselectively converted into 3,5-dideoxy-4-O-(methoxymethyl)-3,5-di-C-methyl-6-O-pivaloyl-l-talose ethylene dithioacetal (31) via 3,5-dideoxy-4-O-(methoxymethyl)-3,5-di-C-methyl-l-talopyranuro-6,2-lactone ethylene dithioacetal (24) in 10 steps (23.6% overall yield). Desulfurization [Raney Ni W-4, 92% yield] of 31 followed by three-step transformation (91% yield) afforded 2,4,6-trideoxy-5-O-(diethylisopropylsilyl)-3-O-(methoxymethyl)-2,4-di-C-methyl-l-altrose, which was olefinated by using methyl (2E,4E)-6-(dimethoxyphosphinyl)-2,4-hexadienoate twice to give the target compound, all-trans-hexaenal 4 (12 steps, 38.6% overall yield from 31).
Chemical Synthesis of a Biosynthetic Precursor of Lipid A with a Phosphorylated Tetraacyl Disaccharide Structure
Authors: Imoto Masahiro , Yoshimura Hiroyuki , Yamamoto Michiharu , Shimamoto Tetsuo , Kusumoto Shoichi , Shiba Tetsuo 
Published: July 2006

Abstract
2,2′-N:3,3′-O-Tetrakis[(R)-3-hydroxytetradecanoyl]-β(1-6)-d-glucosamine disaccharide 1,4′-bis(phosphate) and its dephospho derivatives were synthesized. The bisphosphate prepared was shown to be identical with a natural biosynthetic precursor of lipid A which corresponds to the lipophilic part of lipopolysaccharide (LPS) in bacterial cell wall. The synthetic bis- and monophosphates exhibited many of typical endotoxic activities of LPS. Consequently, this work established the chemical structure of the biosynthetic precursor of lipid A and elucidated the fundamental structure required for the expression of these activities.
Total Synthesis of Escherichia coli Lipid A, the Endotoxically Active Principle of Cell-Surface Lipopolysaccharide
Authors: Imoto Masahiro , Yoshimura Hiroyuki , Shimamoto Tetsuo , Sakaguchi Nobuki , Kusumoto Shoichi , Shiba Tetsuo 
Published: July 2006

Abstract
Chemical syntheses are described of polyacylated β(1→6) glucosamine disaccharide 1,4′-bis(phosphate), which corresponds to the proposed structure of E. coli lipid A, and of its dephospho derivatives. The synthetic bisphosphate proved to be identical with the corresponding natural specimen. The chemical structure of lipid A was thus established.
Catalase-Like Activity of Anion-Exchange Resin Modified with Metalloporphyrin in the Oxidation of Methyl Alcohol and Its Application to the Determination of Hydrogen Peroxide
Authors: Saito Yutaka , Satouchi Mitsuko , Mifune Masaki , Tai Takaaki , Odo Junichi , Tanaka Yoshimasa , Chikuma Masahiko , Tanaka Hisashi 
Published: July 2006

Abstract
The catalase-like activity of anion-exchange resins (Amberlite IRA 900) modified with various metalloporphyrins in the acceleration of reaction (1) was evaluated by efficiency in color reaction (2) based on dye formation:
H2O2+CH3OH\oversetcatalase\ightharpoonup2H2O+HCHO (1)
HCHO+4-amino-3-hydrazino-5-mercapto-1,2,4-triazole+KIO4\oversetOH−\ightharpoonupDye(λmax=550 nm). (2)
Amberlite IRA 900 modified with Mn3+–tetrakis(sulfophenyl)porphine (MnTPPSr) was found to exhibit the highest catalase-like activity among the resins tested and was applied as a mimesis of catalase to the determination of hydrogen peroxide by the use of reactions (1) and (2). The molar absorption coefficient for hydrogen peroxide was found to be 2.37×104 mol−1 dm3 cm−1, which is larger than twice that in the control catalase method (0.97×104 mol−1 dm3cm−1). Interferences by common foreign substances tested were found to be small. MnTPPSr gave a better result than catalase in the determination of hydrogen peroxide.
The Synthesis of Ar-abietatrien-12,16-oxide and Its C-15 Epimer
Authors: Matsumoto Takashi , Imai Sachihiko , Yoshinari Takashi , Tsuruta Kazuaki 
Published: July 2006

Abstract
In order to elucidate the absolute configuration of C-15 in natural ar-abietatrien-12,16-oxide, (15R)-12,16-epoxy-8,11,13-abietatriene (1a) and its (15S)-epimer (1b) have been synthesized. Treatment of (15R)-8,11,13-abietatriene-12,16-diol with a mixture of chloromethyl methyl ether, dicyclohexano-18-crown-6, and potassium carbonate afforded 1a as a minor product and (15R)-12-methoxymethyl ether as a major product. The latter was further converted into 1a. A similar treatment of (15S)-8,11,13-abietatriene-12,16-diol gave 1b. Catalytic hydrogenations of 12,16-epoxy-8,11,13,15-abietatetraene, methyl 12,16-epoxy-8,11,13,15-abietatetraen-19-oate (5), and methyl 12,16-epoxy-8,11,13,15-abietatetraen-18-oate (7) afforded the corresponding (15R)-dihydrobenzofuran derivatives and their (15S)-epimers. Conversions of the hydrogenation products from 5 and 7 into 1a and 1b were also carried out. The synthetic 1a was identical with natural ar-abietatrien-12,16-oxide.
Preparation, Absolute Configuration and Conformation of Some α-Aryl-2-pyridylmethanols
Authors: Bojadziev Stefan E. , Tsankov Dimiter T. , Ivanov Petko M. , Berova Nikolina D. 
Published: July 2006

Abstract
The syntheses of five optically active α-aryl-2-pyridylmethanols 1–5 are described. It is shown by means of chemical correlation with the known (−)-(αR,2S)-α-phenyl-2-piperidylmethanol 6 that all levo-rotatory isomers of 1–4 are of R configuration. It is also found via the relative integral intensities in the infrared spectra of the bands due to free and intramolecularly bonded hydroxyl groups in the compounds 1–4 and the free hydroxyl groups in the model compounds 7–10, that the population of the conformers with an intramolecular OH···N bond in compounds 1–4 exceeds 80%.
Clay Montmorillonite-Catalyzed Aldol Reactions of Silyl Ketene Acetals with Carbonyl Compounds
Authors: Onaka Makoto , Ohno Ryosuke , Kawai Motomitsu , Izumi Yusuke 
Published: July 2006

Abstract
Al3+ ion-exchanged montmorillonite efficiently catalyzes the aldol reactions of silyl ketene acetals with carbonyl compounds and acetals. The optimum preparation of the effective montmorillonite catalyst is described.
63Cu High Resolution NMR of Cu(I) Halides in Aqueous Solution and Suspension
Authors: Endo Kazunaka , Yamamoto Kyonosuke , Deguchi Kenzo , Matsushita Kazuhiro 
Published: July 2006

Abstract
In an aqueous solution, 63Cu chemical shielding order ([CuCl4]3− \simeq[CuBr4]3−&lt;[CuI4]3−) and line widths (10 to 30 kHz) for CuX–KX systems(where X=Cl, Br, I) have been obtained. The chemical shift(−694 ppm) between [CuCl4]3− and [Cu(CN)4]3− is interpreted by the paramagnetic term which depends mainly upon a 3d-hole on a Cu(I) atom by using perturbation theory with an average excitation energy approximation. The linebroadening of Cu(I) halide complexes in aqueous solution is explained dominantly by a Cu(I) nuclear quadrupole interaction with the electric field gradient which arises from a 3d-hole on a Cu atom. For the abnormal increasing metal shielding order of [MX4](4−i)−([MCl4](4−i)−≤[MBr4](4−i)−&lt;[MI4](4−i)−), a possibility of the heavyatom effect in the metal shielding of [CuI4]3−(649 ppm, using the lowest excitation energy of the diatomic molecule) and [CdI4]3−(1941 ppm using the lowest excitation energy of the diatomic molecule), is evaluated.
The Photocycloaddition of N-Vinylcarbazole with 3-Cyanostyrene
Authors: Tsuchida Akira , Yamamoto Masahide , Nishijima Yasunori 
Published: July 2006

Abstract
The photocycloaddition reaction of N-vinylcarbazole (VCZ) as an electron donor, with 3-cyanostyrene as an electron acceptor, was studied. In nonpolar solvents, two cyclobutanes of cis-1-(9-carbazolyl)-2-(3-cyanophenyl)cyclobutane and trans-1-(9-carbazolyl)-2-(3-cyanophenyl)cyclobutane (in a ratio of 3 : 1) were obtained from an exciplex intermediate. The structure of cis cyclobutane seemed to originate from a sandwich conformation of the exciplex. In polar solvents, a photodissociation to free ion radicals was observed and trans-1,2-di(9-carbazolyl)cyclobutane was produced efficiently by means of a chain mechanism via a cation radical of VCZ. Transient intermediates were measured by means of nanosecond laser photolysis; the results supported the reaction scheme.
Silver–Gelatin Method for the Determination of Trace Amounts of Carbon Monoxide in Air
Authors: Pal Tarasankar , Ganguly Ashes , Maity Durga S 
Published: July 2006

Abstract
The use of silver–gelatin complex was found suitable for the determination of trace amounts of carbon monoxide in air. Silver–gelatin complex is reduced by carbon monoxide to give intensely colored sol. Measurement of the color intensity of the stable silver sol enables the determination of carbon monoxide successful under various environmental conditions. The detection limit is 2–100 ppm. The relative standard deviation for the determination of 10 ppm carbon monoxide is 2.6%.
The Effect of the Electrical Potential Difference on the Adsorption of the Hexadecyltrimethylammonium Ion at the Polarized Nitrobenzene–Water Interface
Authors: Kakiuchi Takashi , Kobayashi Miki , Senda Mitsugi 
Published: July 2006

Abstract
The adsorption of the hexadecyltrimethylammonium ion(HTMA+) at the polarized nitrobenzene–water interface has been studied using electrocapillary measurements. The adsorption of HTMA+ was found to be markedly dependent on the potential drop across the interface. HTMA+ exhibited no specific adsorption in the potential range where the aqueous phase is positive, whereas a strong adsorption occurred in the potential range where the electric potential in the aqueous phase is negative with respect to that in the nitrobenzene. The adsorption free energy depends linearly on the potential difference across the interface. The specific adsorption of HTMA+ significantly alters the double-layer structure. The outer Helmholtz potential in the nitrobenzene phase was inverted from negative to positive due to the adsorption of HTMA+ ions.