bluuebunny/crossref_metadata_2025 huggingface dataset:
Charge-Transfer Complexation in Aqueous Polyelectrolyte Solution. II. Interaction between Polycations and CT Complexes
Authors: Itaya Tomoyuki , Kawabata Yoshiya , Ochiai Hiroshi , Ueda Kazuyoshi , Imamura Akira
Published: July 2006

The CT complexation between 9,10-dimethoxyanthracene-2-sulfonate ion (DMACS−; donor) and 9,10-anthraquinone-2-sulfonate ion (AQS−; acceptor) has been studied in aqueous solution of poly(1,1-dimethyl-3,5-dimethylenepiperidinium chloride) (PDDP+Cl−). In aqueous PDDP+Cl− solution, both DMACS− and AQS− are electrostatically bound to the polyion and the CT complex between them is formed around the polyion due to the close proximity of DMACS−–AQS− pairs. By comparing the CT complexation in aqueous PDDP+Cl− solution with that in aqueous poly(allylammonium chloride) (PAAH+Cl−) solution studied previously, the effects of the charge density of the polyion, the structure of charged groups on the polyion and the local conformation of the polyion upon the CT complexation have been clarified. A plausible structure of the CT complex has been determined so as to satisfy the symmetry-allowed interaction between the HOMO of DMACS− and the LUMO of AQS−. The CT complex interacts more strongly with the polyion than Cl− and the decrease in the viscosity of the polymer (the contraction of the polymer chain) is more effectively caused by the CT complexation. Moreover, the strength of the association (stacking interaction) of aromatic counterions (DMACS−, AQS−) including the CT complexation affects the binding of these counterions to the polyion.
Thermal Membrane Potential across Anion-Exchange Membranes in Various Electrolyte Solutions and the Transported Entropy of Ions
Authors: Hanaoka Kokichi , Kiyono Ryotaro , Tasaka Masayasu
Published: July 2006

The thermal membrane potential cell with solution inlet channels was constructed from two blocks of poly(methyl methacrylate). Using the cell the thermal membrane potentials across anion-exchange membranes Aciplex A-201, A-211, and A-221, and Neosepta AM-1 were observed in inorganic electrolytes: KF, KCl, KI, KNO3, KClO3, and KIO3, and in organic electrolytes: HCOONa, CH3COONa, CH3COOK, and C6H5COONa. The thermal membrane potential Δψ across the anion-exchange membrane was always positive at the cold solution side. The temperature coefficient of the thermal membrane potential per unit temperature difference Δψ/ΔT is proportional to the logarithmic activities of the ions and the slope of this plot was R/F in the range of ideal permselectivity for the counterions except Aciplex A-221. The transported entropies of the counterions in the membrane were estimated by combining data for the thermal membrane potential, thermoosmosis, and electroosmosis. For all types of membranes, both terms of water and ions in the thermal membrane potential increased with the increasing of the friction coefficient of ions.
Total Inhibition of the Oxygen Reduction Reaction at Au(111) by Copper Adlayers in Sulfuric Acid Solution
Authors: Abe Takayuki , Miki Youichiro , Itaya Kingo
Published: July 2006

The influence of an underpotentially deposited adlayer of copper on the oxygen reduction reaction (ORR) at Au(111) has been studied in a 0.05 M H2SO4 solution using hanging meniscus rotating disk voltammetry. The total inhibition of the ORR was found after the formation of the first Cu adlayer. Two possible structures for the Cu adlayer on Au(111) take into account inhibition of the ORR. The total inhibition observed in the present study can be explained by a honeycomb (√3 × √3)R30° structure, rather than a simple (√3 × √3)R30° Cu adlayer. A bridging two-site process (disproportionation reaction) is not expected to occur on the honeycomb Cu adlayer.
Binding of Local Anesthetic Tetracaine to Phospholipid Mixed Vesicles
Authors: Fukushima Kohsuke , Someya Masayuki , Shimozawa Ryosuke
Published: July 2006

We measured the binding isotherms of a local anesthetic, tetracaine, to dilauroylphosphatidic acid (DLPA) and dilauroylphosphatidylcholine (DLPC) mixed vesicles along with their pure vesicles. The binding isotherms were constructed by the equilibrium dialysis method at different pH (5.5, 7.0, 8.0) at 35 °C. The binding isotherms were analyzed based on the equations combined with Langmuir and Hill-type isotherms, and the parameters characterizing the binding isotherms were evaluated. The thus-obtained binding parameters for pure vesicles well reproduce the binding isotherms for the mixed vesicles by taking account of the mixing ratios. This indicates that DLPA and DLPC also provide independent binding sites for tetracaine, as for previously reported dibucaine. The estimated values of the binding parameters for these two anesthetics, i.e., tetracaine and dibucaine, were compared in terms of the strength of the anesthetic action as well as the molecular structure.
Kinetics and Mechanisms of Photoinduced Electron-Transfer Reaction of Magnesium Myoglobin
Authors: Tsukahara Keiichi , Nishikawa Yuki , Kimura Chieko , Sawai Naoko , Sakurai Takeshi
Published: July 2006

Horse heart metmyoglobin was reconstituted with magnesium(II) porphyrin, [Mg(dp)] (3,7,12,17-tetramethyl-2,18-bis(2-carboxyethyl)porphyrinatomagnesium(II)). Photoinduced electron-transfer (ET) between magnesium myoglobin (MgDPMb) and cationic and anionic quenchers, such as viologens and anthraquinone-2-sulfonate (AQS−), has been studied in an aqueous degassed solution. None of the quenchers examined in this work formed a detectable associated complex with MgDPMb. The thermal backward ET reaction was observed for these quenchers. Not only photoinduced ET but also thermal backward ET reactions were insensitive to the driving force of the reactions. Moreover, there was little effect of metal-ion substitution; the rate of reaction was similar to that for zinc myoglobin. Thus, the reactions are controlled by conformational changes in the myoglobins.
Chemical Amplification Method by Spectrophotometry for the Determination of Trace Amounts of Selenium
Authors: Ramesh A , Ramakrishna T V , Subramanian M S
Published: July 2006

A rapid and sensitive spectrophotometric method has been developed based on the extraction of the ion-association complex formed between ICl2− and Rhodamine 6G+ into benzene. The ICI2− is formed through iodine which is liberated during the oxidation of iodide by the selenium(IV) present in sulfuric acid medium. The method is sensitive and down to 0.1 μg selenium could be determined in an aqueous phase volume of 10 ml. The extracted Rhodamine 6G+–ICl2− complex has a molar absorptivity of 4.8 × 105 dm3 mol−1 cm−1 at 535 nm. Beer’s law is obeyed over the range 0.1 to 0.9 μg of selenium. The relative standard deviation is 2.4%. The method is made more sensitive and selective by adopting the aluminium hydroxide collection procedure. The interference of few ions such as Fe3+, VO3−, TeO32− and Sb5+ which were collected along with selenium on aluminium hydroxide, were overcome by adding proper masking agents. The method was applied to the determination of selenium in environmental ash sample, copper ore, bark sample, and shampoo preparations.
Synthesis, Structure, and Magnetic Property of Linear Chloro-Bridged Nickel(II) Tetramer with Dinucleating Bis-dimethylcyclam Ligand
Authors: Kajiwara Takashi , Yamaguchi Tadashi , Oshio Hiroki , Ito Tasuku
Published: July 2006

A new nickel(II) complex with the composition of Ni2Cl2(L)(ClO4)2·1.5H2O (L = α,α′-bis(5R(S),7S(R)5,7-dimethyl-1,4,8,11-tetraazacyclotetradecan-6-yl)-o-xylene) has been prepared via a four coordinate complex [Ni2(L)] (ClO4)4·3H2O from [Ni2(μ-Br)Br2(L)]Br·H2O. The compound crystallizes in orthorhombic space group Ccm21 with cell parameters at −80 °C, a = 21.90(1), b = 20.28(1), c = 19.63(1) Å, V = 8718(1) Å3, Z = 8. The crystal consists of the cationic dinuclear unit [Ni2(μ-Cl)Cl2(L)]+, the counter anion ClO4−, and water of crystallization. In [Ni2(μ-Cl)Cl2(L)]+, three chloride ions and two nickel ions are alternately arranged in an almost linear manner, and two cyclam rings with the most stable trans-III type conformation are arranged in a face-to-face manner. This cationic dinuclear unit is further connected to each other by sharing the terminal Cl ligand to form pseudo one-dimensional chain structure of the ···Cl–Ni–Cl–Ni–Cl··· type. However, one of the Cl atoms which bridges the dinuclear units is statistically disordered at two positions along the chain and thereby the repeating unit in the chain is a chloro bridged dimer of the dinucleating ligand complex. The neighboring Ni–Cl distances range from 2.568(4) to 2.855(4) Å. The temperature dependent magnetic behavior in the range of 25—300 K has been interpreted by the usual Heisenberg–Dirac–Van Vleck model, assuming that only three Ni(II) ions in {Ni2Cl2(L)}2 are paramagnetic. The best fit parameters were J = −48.2(3) and J′ = −11.2(3) cm−1 for = −2J(S1·S1′) − 2J′(S1·S2).
Dithiooxalato(dto)-Bridged Bimetallic Assemblies {NPr4[MCr(dto)3]}x (M = Fe, Co, Ni, Zn; NPr4 = Tetrapropylammonium Ion): New Complex-Based Ferromagnets
Authors: Okawa Hisashi , Mitsumi Minoru , Ohba Masaaki , Kodera Masahito , Matsumoto Naohide
Published: July 2006

The reaction of potassium calcium tris(dithiooxalato)chromate(III) hexahydrate KCa[Cr(dto)3]·6H2O, a metal(II) salt and a tetrapropylammonium bromide (NPr4Br) in aqueous methanol forms bimetallic assemblies {NPr4[MCr(dto)3]}x (M = Fe (1), Co (2), Ni (3), Zn (4)), where the dto group bridges Cr(III) and M(II) ions through the sulfur atoms to Cr(III) and through the oxygen atoms to M(II) to provide an alternate array of Cr(III) and M(II) ions. The magnetic susceptibility data for 1—3 in the temperature range 5—300 K obey the Curie Weiss law (χM−1 = (T − θ)/C) with a positive Weiss constant (+18 K for 1, +24 K for 2, and +41 K for 3), and the effective magnetic moments increase with decreasing temperature. The megnetization studies (field-cooled magnetization, remnant magnetization, and zero-field cooled magnetization) reveal the ferromagnetic phase transition at TC = 8, 16, and 23 K for 1, 2, and 3, respectively. The assembly 4 shows paramagnetic behavior in the temperature range of 5—300 K.
Nucleophilic Reaction upon Electron-Deficient Pyridone Derivatives. XIII. Regioselective Synthesis of 2-Substituted 3-Nitropyridines by One-Pot Reaction of Either 4- or 6-Substituted 1-Methyl-3,5-dinitro-2-pyridones with Ketones and Ammonia
Authors: Tohda Yasuo , Kawahara Tohru , Eiraku Miyuki , Tani Keita , Nisiwaki Nagatoshi , Ariga Masahiro
Published: July 2006

A one-pot synthesis of 2-substituted 3-nitropyridines was developed by a ring transformation of 6- or 4-substituted 1-methyl-3,5-dinitro-2-pyridones (2 or 3) with ammonia and enamines derived from ketones. Some intermediates having a 2,6-diazabicyclo[3.3.1]nonane skeleton were isolated from reactions of 3. The ring transformation proceeds via an addition-addition-elimination-elimination mechanism. Few competitive isomeric by-products, 4-substituted 3-nitropyridines and 4-nitroanilines, were formed. All the 2 substrates showed good reactivity, but the 3 substrates having electron-withdrawing substituents were less reactive and selective. 1,4,6-Trimethyl-3,5-dinitro-2-pyridone did not gave any products. The selectivity is interpreted in terms of differences of thermodynamic (main selection rule B) and kinetic stability (minor selection rule A) between the possible bicyclic intermediates which are expected to be formed via the mechanism.
Synthesis of Unsymmetrical 2,3-Diaryl- and 2,4-Diarylthiophenes Starting from 2,5-Dichlorothiophene
Authors: Sone Tyo , Sato Kazuaki , Umetsu Yasuhiro , Yoshino Akihiro , Takahashi Kensuke
Published: July 2006

Unsymmetrically substituted 2,4-diaryl- and 2,3-diarylthiophenes were synthesized from 2,5-dichlorothiophene via 4-aryl-2-chlorothiophenes in two and four steps including Ni-mediated cross-coupling, respectively. Aluminum chloride-catalyzed reaction of 3-aryl-2-chlorothiophenes with some aromatic ethers unexpectedly led to the formation of the corresponding 2,4-isomers.
Oxidation of Nucleic Acid Related Compounds by the Peroxodisulfate Ion
Authors: Itahara Toshio , Yoshitake Takashi , Koga Sunao , Nishino Akihiro
Published: July 2006

The treatment of nucleic acid bases, nucleosides, and nucleotides with peroxodisulfate ion in a phosphate buffer solution at pH 7.0 or water at 70—75 °C was investigated. The reaction of thymine and 5-methylcytosine nucleosides and nucleotides resulted in the oxidation of the 5-methyl groups. The oxidation products from 1,3-dimethyluracils and the time-course of the reaction of uracils led to two plausible reaction mechanisms for the oxidation of uracils.
Perfluoroalkyl-Chalcogenation of Alkynes
Authors: Ueda Yasufumi , Kanai Masatomi , Uneyama Kenji
Published: July 2006

Perfluoroalkyl-telluration of alkynes has been performed by a (PhTe)2–NaBH4–RfX system at a low temperature (−40, −80, or −100 °C) to give 2-(perfluoroalkyl)vinyl tellurides. Meanwhile, perfluoroalkyl-sulfenylation and perfluoroalkyl-selenation were less effective. The perfluoroalkyl-telluration proceeds mainly via both SRN1 process and photochemical addition of the in situ formed perfluoroalkyl phenyl telluride (RfTePh). The efficiency of the chalcogenolate anions for perfluoroalkyl-chalcogenation was found to be the order of PhS− < PhSe− < PhTe−.
Conductance Measurements in Corrosion and Inhibition of Al and Al–Mn Alloy
Authors: El-Cheikh Fathla M , Assaf Fawzi H , Khodari Mahmoud , Ghandour Mahmoud A , Krisha Mortaga M Abou
Published: July 2006

Studies were performed to determine the effect of 2-picoline, 3-picoline, 4-pyridinol, and 2-pyridinamine on the dissolution of untreated, anodized, and sealed aluminum and aluminum–manganese alloys at 30.0 and 40.0 °C. Conductance measurements were applied to evaluate the corrosion rate. A comparison was carried out between this newly suggested conductance method and other methods previously used to estimate the dissolution rate. This comparison shows of the reliability of this conductance method. A good correlation was observed between the basicity, structure, and the inhibition effect of all compounds investigated. The order of inhibition efficiency is increasing as: 2–pyridinamine > 4–pyridinol > 3–picoline > 2–picoline. This order described above is consistent with the evidence that the oxidized specimens show higher inhibition in the presence of additives than sealed and untreated ones.
Purification of CO Based on Selenium-Amine-CO Chemistry
Authors: Tsunoi Shinji , Miyoshi Noritaka , Ogawa Akiya , Kambe Nobuaki , Sonoda Noboru
Published: July 2006

Efficient separation of carbon monoxide from a binary mixture of carbon monoxide and hydrogen with selenium and secondary amines has been developed. The process consists of (i) selective reaction of CO with selenium and a secondary amine to form the corresponding ammonium carbamoselenoate 1 and (ii) thermolysis of 1 to form pure CO (99.9%) quantitatively. A Se–alcohol system is also usable but the results are inferior to that with a Se–amine system.
Crystal Structure of Potassium Hydrogen Terephthalate: Symmetric Hydrogen Bond in One-Dimensional Chain
Authors: Miyakubo Keisuke , Takeda Sadamu , Nakamura Nobuo
Published: July 2006

Crystal structure of potassium hydrogen terephthalate was determined by X-ray diffraction. Crystals have monoclinic unit cells with C2/c, a = 18.776(6), b = 3.761(3), c = 11.150(4) Å, β = 94.72(3)°, V = 784.6(6) Å3, and Z = 4. Acid anions form a one-dimensional chain linked by short (RO···O = 2.459(3) Å) and symmetric hydrogen bonds. The acidic hydrogen was distributed at two equivalent sites in the hydrogen bond.
Spectroscopic Study of the Conformational Dependence on Acid Dissociation of Phenoxypyridinium Cations
Authors: Uno Bunji , Kawakita Toshio , Kano Kenji , Okumura Noriko , Goto Masashi , Kubota Tanekazu
Published: July 2006

Thermodynamic constants for acid dissociation of the 2-, 3-, and 4-phenoxypyridinium, and 2-(2,6-xylyloxy)pyridinium cations were estimated by the spectroscopic method, and are extensively discussed in relation to the conformations around the bridging oxygen atom and the electronic states.
Dipole Moment of the Excited Tetracarbonyl(2,2′-bipyrazine)molybdenum
Authors: Shinozaki Kazuteru , Kaizu Youkoh
Published: July 2006

Visible absorption maxima of [Mo(CO)4(bpz)] and [Mo(CO)4(bpy)] depend on solvent, while their emission maxima are less sensitive to solvent. These molybdenum carbonyl complexes have a large dipole moment in the ground state, but a small dipole moment in the MLCT excited state. These results suggest that π back donation from metal to CO ligands occurs in the ground state, whereas a counter migration of the other electron from the ligands to metal accompanied by photoexcitation occurs in the MLCT state.
Kinetics and Mechanism of the Oxidative Cleavage of Unsaturated Acids by Quinolinium Dichromate
Authors: Nongkynrih Irona , Mahanti Mahendra K
Published: July 2006

Quinolinium dichromate (QDC) oxidizes cinnamic and crotonic acids smoothly in N,N-dimethylformamide in the presence of an acid. The reaction has a unit dependence on each of the substrate, oxidant, and acid concentrations. The mechanistic pathway involves an electrophilic attack of the oxidant on the double bond of the substrate, giving a carbonium-ion intermediate. This is supported by a small inverse kinetic isotope effect (kH/kD = 0.78) at the α-carbon and the value of ρ = −4.0.
Formylation of Aryl Halides with Carbon Monoxide and Sodium Formate in the Presence of Palladium Catalyst
Authors: Okano Tamon , Harada Nobuyuki , Kiji Jitsuo
Published: July 2006

The formylation of aryl bromides or iodides with HCOONa at atmospheric pressure of CO readily proceeded in the presence of PdCl2(PPh3)2 in DMF to afford the corresponding aldehydes in good yields. The contamination with water promoted a side reaction to form carboxylic acids. The formylation using HCOOK or HCOONH4 as a hydride source was fast but gave a considerable amount of the reduction product.
Side-Chain Bromination of Diphenylmethanes, 1,2-Diphenylethanes, and 10,11-Dihydro-5H-dibenzo[a,d]cycloheptenes with N-Bromosuccinimide under Irradiation of a Tungsten Lamp
Authors: Mataka Shuntaro , Liu Guo-Bin , Tori-i Akiyoshi , Tashiro Masashi
Published: July 2006

The photothermal bromination of diphenylmethane and methyl derivatives with N-bromosuccinimide afforded benzophenone and (polybromomethyl)benzophenones via the hydrolysis of dibromodiphenylmethanes. 1,2-Diphenylethane and p-t-butyl derivative gave dibromostilbenes, while the o-methyl derivative afforded bis(dibromomethyl)dibromodiphenylethane. 10,11-Dihydro-5H-dibenzo[a,d]cycloheptene gave 9-bromodibenzocycloheptenone, which was also obtained in the bromination of 10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-one.
An Improved Synthesis of (±)-Otonecine and a Synthesis of a 12-Membered Otonecine Diester
Authors: Niwa Haruki , Sakata Tomoyo , Yamada Kiyoyuki
Published: July 2006

(±)-4-Methyl-1-phenylthio-8-oxa-4-azabicyclo[5.2.1]decane-9,10-dione was efficiently converted into (±)-otonecine, which was regioselectively coupled with (E)-2-ethylidenehexanedioic acid to give a 12-membered otonecine diester.
Quantification Analysis of 3′-Splice Signal Sequences in mRNA Precursors. Mutations and Exon Skipping in Rabbit β-Globin Gene
Authors: Iida Yôichi
Published: July 2006

The signals which direct excision of introns from mRNA precursors in mammalian genes have been studied. The consensus sequence for the 3′-splice site is (T or C)11N(C or T) AG/G, where N is A, G, C or T, and where the stroke (/) indicates the boundary between intron and exon. In the present research, the nucleotide sequence at the 3′-splice junction in rabbit β-globin gene was analyzed by a quantification method proposed previously. Using a sample score of 16-nucleotide sequence at the 3′-splice junction, we proposed the strength of the 3′-splice signal. This approach could explain not only the location of the authentic 3′-splice sites in rabbit β-globin pre-mRNA but also the experimental results of various point mutations introduced into the 3′-splice region of the second intron. Our analysis also explains a skipping mechanism of the second exon, in which the first exon is spliced directly to the third exon if the 5′-splice site of the second intron is destroyed.
Crystal Structure of Organic Metamagnet: 4-Methacryloyloxy-2,2,6,6-tetramethyl-1-piperidinyloxyl (MOTMP)
Authors: Kajiwara Atsushi , Sugimoto Hiroyuki , Kamachi Mikiharu
Published: July 2006

Structures of 4-methacryloyloxy-2,2,6,6-tetramethyl-1-piperidinyloxyl (MOTMP) and 4-acryloyloxy-2,2,6,6-tetramethyl-1-piperidinyloxyl (AOTMP) which have one-dimensional ferromagnetic coupling and antiferromagnetic interactions, respectively, have been determined by X-ray crystallographic analysis. The crystals of both compounds are monoclinic and have space group P21 (No. 4) with Z = 2. The one-dimensional ordering of spins of NO radicals is explained by intermolecular superexchange interactions of NO radicals due to NO radical ···C=C–C=O···NO radical contacts shorter than the van der Waals radii sum (ca. 3.6 Å). The difference in magnetic behavior between MOTMP and AOTMP might be due to the difference in the torsion angle of the C=C–C=O moiety, as in the three-dimensional molecular arrangement in the crystals.
The Mechanism of the Enantioselective Photocyclization of 2-Piperidone in the Clathrate Crystal
Authors: Hashizume Daisuke , Ohashi Yuji , Tanaka Koichi , Toda Fumio
Published: July 2006

The achiral molecules of N-(arylcarbonylmethyl)-2-piperidones form 1 : 1 host–guest complexes with the chiral host molecule derived from tartaric acid. The guest molecules in the clathrate crystals are converted into the chiral 7-aryl-7-hydroxy-1-azabicyclo[4.2.0]octan-2-one derivatives with high optical yields on exposure to a high pressure Hg lamp. The crystal structures and absolute configurations of the clathrate compound (5a), which consists of (−)-(2R,3R)-2,3-bis(hydroxydiphenylmethyl)-1,4-dioxaspiro[4.5]decane (4) and N-(p-bromophenylcarbonylmethyl)-2-piperidone (1a), and of the chiral product of (−)-(6S,7S)-7-hydroxy-1-azabicyclo[4.2.0]octan-2-one (2a) were determined by X-rays. (5a) C34H34O4·C13H14NO2Br, fw = 802.81, monoclinic C2, a = 24.186(3), b = 9.550(3), c = 19.711(3) Å, β=116.18(1)°,V = 4086(2) Å3, Z = 4, final R became 0.047. (2a) C13H14NO2Br, fw = 296.16, orthorhombic, P212121, a = 7.047(2), b = 31.151(3), c = 5.696(2) Å, V = 1250.3(5) Å3, Z = 4, final R became 0.039. The enantioselectivity of the photocyclization is clearly explained by the two structures if we assume that the reaction proceeds topochemically.
Cadmium(53P1)-Photosensitized Luminescence of Some Compounds Containing Three Donor Atoms
Authors: Ahmed Omar , Sueishi Yoshimi , Nishimura Norio , Yamamoto Shunzo
Published: July 2006

The cadmium photosensitized luminescence of some compounds containing three donor atoms (N and/or O) has been investigated by the steady illumination method at temperatures between 453 and 553 K. Broad emission spectra in the visible region were observed with diethylenetriamine (DETA), dipropylenetriamine (DPTA), bis(2-methoxyethyl) ether (BMOEE), bis-2-methoxyethylamine (BMOEA), and bis-(dimethylaminoethyl) ether (BDAEE). By comparing each of these spectra with the spectra of the corresponding bifunctional compounds, we can resolved these spectra into three component bands for DETA, DPTA, BMOEE, and BMOEA, and into four component bands for BDAEE. The longest wavelength bands were observed for the first time. They can be assigned to different types of 1 : 1 exciplexes (acyclic, monocyclic, and bicyclic). The enthalpy changes of the chelations were evaluated from the temperature dependences of the intensities of the bands and were found to depend on the type of chelating atom.
Direct Determination of the Interaction Potentials of Ar–Xe, Kr–Xe, and Ar–Kr from the Extended Principle of Corresponding States
Authors: Goharshadi Elaheh K , Boushehri Ali
Published: July 2006

Intermolecular pair-potential energy functions are given for all the unlike interactions of Ar, Kr, and Xe. The potentials are determined by direct inversion of experimental reduced viscosity collision integrals obtained from the corresponding-states correlation. The results are in good agreement with the potentials proposed by Ron Aziz.
Synthesis, X-Ray Analysis, and Electrochemical Study of Some Manganese Carbonyl Derivatives with 1,1′-Bis(diphenylphosphino)ferrocene, dppfe
Authors: Onaka Satoru , Haga Masa-aki , Takagi Shigeru , Otsuka Mayumi , Mizuno Katuya
Published: July 2006

Synthesis and X-ray structure analyses were carried out for fac-cis-[MnCl(CO)3dppfe] and fac-cis-[MnH(CO)3dppfe], and a cyclic voltammetric study was made for a series of manganese carbonyl derivatives with 1,1′-bis(diphenylphosphino)ferrocene (dppfe), including these new compounds. Unusually a low oxidation potential for the Mn site is revealed for [Mn(MeCp)(CO)dppfe]. A good correlation between ν(CO) and the oxidation potential for the Mn atom has been clarified.
Oxidative Decomposition of Chlorobenzene over Calcium-Deficient Hydroxyapatite
Authors: Nishikawa Harumitsu , Monma Hideki
Published: July 2006

Gaseous chlorobenzene was decomposed into CO and CO2 by the oxidative reaction at 400—450 °C over calcium-deficient hydroxyapatite (DAp) prepared by an aqueous precipitation procedure. Phenol and benzene were not detected after the reaction. Most of the Cl in chlorobenzene was captured as Cl- in DAp by the reaction. On the other hand, the DAp prepared by the hydrolysis of α-tricalcium phosphate was inactive for the decomposition of chlorobenzene. The difference in the activity between the two DAp materials was attributed to the difference of their crystallinities.
Study of Synthetic Clay Minerals. III. Synthesis and Characterization of Two Dimensional Talc
Authors: Takahashi Noriyuki , Tanaka Masanori , Satoh Teiji , Endo Tadashi
Published: July 2006

“Two dimensional” talc was prepared by the hydrothermal reaction of various silicas with magnesium hydroxide. The precipitated and activated silicas were especially available as starting materials. The powder X-ray diffraction data indicated that the resulting talc consisted of no-stratified and random layered structure. According to the IR spectrum, no solid acidity, i.e. Brønsted and Lewis acid sites were found. The specific surface area was over 500 m2 g−1. A large amount of water was adsorbed and partially combined with the surface of lamellar talc. As a result, the artificial talc would receive applications such as emulsifying agents to the mixture of liquid paraffin and water.
The Structures of Azedarachins, Limonoid Antifeedants from Chinese Melia azedarach Linn
Authors: Huang Ruo Chun , Okamura Hiroaki , Iwagawa Tetsuo , Nakatani Munehiro
Published: July 2006

Three azedarachins, insect antifeedant limonoids, have been isolated from the root bark of Chinese Melia azedarach Linn (Meliaceae), along with six trichilins. Their structures show a 14,15-epoxide and a 19/29 acyl acetal bridge system, as elucidated by spectroscopic studies. They are antifeedants active against the larvae of Spodoptera exigua Hübner (Boisduval).
An Improved Asymmetrically-Modified Nickel Catalyst Prepared from Ultrasonicated Raney Nickel
Authors: Tai Akira , Kikukawa Tadashi , Sugimura Takashi , Inoue Yoshihisa , Abe Satoshi , Osawa Tsutomu , Harada Tadao
Published: July 2006

The ultrasonic irradiation of Raney nickel catalyst in water followed by the removal of the resulting turbid supernatant gave an excellent nickel catalyst (RNi-U) which generated an asymmetrically-modified nickel catalyst. An EPMA (SEM-EDX) study indicated that RNi-U consisted of a fairly pure nickel surface of homogeneous size. Tartaric acid–NaBr-modified RNi-U (TA–NaBr–MRNi-U) showed a high enantio-differentiating ability as well as reactivity in the hydrogenation of prochiral ketones such as 1,3-diones and 3-oxoalkanoic acid esters.
Reactions of 2-Hydrazino-1-azaazulenes with Diphenylcyclopropenone
Authors: Abe Noritaka , Kakehi Akikazu
Published: July 2006

The reaction of ethyl 2-hydrazino-1-azaazulene-3-carboxylate with diphenylcyclopropenone (DPP) gave ethyl (Z)-2-[N′-(3-amino-2,3-diphenylpropenoyl)hydrazino]-1-azaazulene-3-carboxylate, ethyl 8,9-diphenyl-1,2,9b-triazaindeno[1,7,6-bcd]azulene-3-carboxylate, ethyl (E)-3-(1,2-diphenylethyl)-1,2,3a-triazacyclopent[a]azulene-9-carboxylate, and ethyl 2-amino-1-azaazulene-3-carboxylate (8a), together with the products of 8a with DPP. However, the reaction of 2-hydrazino-1-azaazulene with DPP gave 4H-2,3-diphenyl-1,4a-diazabenz[a]azulen-4-one, (Z)-3-[(1-azaazulen-2-yl)amino]-2,3-diphenylpropenamide, 3,4-diphenyl-3,4-dihydro-2H-1,4a-diazabenz[a]azulen-2-one and 2-amino-1-azaazulene. The structures of the obtained products were determined by inspections of their physical and spectral data, as well as single-crystal X-ray structure analyses of some of these compounds. The reaction mechanisms are discussed.
Stereoselective Syntheses of α-d- and β-d-Ribofuranosides Catalyzed by the Combined Use of Silver Salts and Their Partners
Authors: Shimomura Naoyuki , Mukaiyama Teruaki
Published: July 2006

α-d-Ribofuranosides are stereoselectively synthesized in high yields from 2,3,5-tri-O-benzyl-1-O-iodoacetyl-d-ribofuranose (1) and trimethylsilylated nucleophiles by the use of silver salts in the coexistence of 3 molar amounts of lithium perchlorate, while β-d-ribofuranosides are prepared predominantly in high yields by the reaction of 1 and trimethylsilylated nucleophiles or 2,3,5-tri-O-benzyl-d-ribofuranose and free alcohols by using [diphenyltin sulfide/silver salt] or [Lawesson’s reagent/silver salt] combined catalyst system.
FLC Mixtures Containing Laterally Fluorinated Compounds with an Acetylene Linkage for the τ–Vmin Mode
Authors: Tamai Kazuhiko , Kaneko Takashi , Shiomi Makoto , Takeda Hitoshi , Koden Mitsuhiro , Miyoshi Shuji , Wada Tomio , Watanabe Tetsuya
Published: July 2006

Achiral liquid crystal mixtures for the τ–Vmin mode of ferroelectric liquid crystals (FLC) were developed by using laterally fluorinated achiral compounds with an acetylene linkage. The achiral mixtures showed large negative dielectric anisotropy (Δε), low viscosity and an INAC phase sequence. FLC mixtures were prepared by doping chiral compounds into the developed achiral mixtures. The developed FLC mixtures showed low Vmin and fast τmin, giving a low driving voltage and fast line address time.
A Novel Synthesis of Alkyl Chloroformate in the Gas Phase by a Palladium-Catalyzed Reaction Using Cl2, CO, and Alkyl Nitrite
Authors: Murakami Masato , Manada Noriaki
Published: July 2006

A novel synthesis of chloroformate was developed by a palladium-catalyzed reaction of Cl2, CO, and alkyl nitrite in the gas phase. When PdCl2/γ-Al2O3 or PdCl2/SiO2 was employed as a catalyst, chloroformate was formed in good yield and with high selectivity. It was confirmed that the reaction did not proceed via phosgene. Cl2 is directly converted to methyl chloroformate. No HCl was formed. The reaction temperature greatly influenced the formation rate of chloroformate, and its selectivity depended on the nitrite/Cl molar ratio very drastically. The dependence of the formation rate on the concentrations of CO and methyl nitrite was also examined.
New Polyacetal Process from Formaldehyde Polymerization in the Presence of a Chain Transfer Agent
Authors: Matsuzaki Kazuhiko , Hata Tadashige , Sone Tatsuo , Masamoto Junzo
Published: July 2006

A new polyacetal process from formaldehyde polymerization in the presence of a chain-transfer agent was developed. For the acetal homopolymer, highly purified formaldehyde is polymerized in the presence of acetic anhydride. Thus, an end-capped polymer can be obtained during polymerization. This concept gave us a very simple process for manufacturing the acetal homopolymer, compared to the conventional process. If trifunctional or tetrafunctional alcoholic compounds are used as chain-transfer agents, branched poly(oxymethylene) is obtained; the melt viscosity of this branched poly(oxymethylene) shows a higher pressure dependence than the linear poly(oxymethylene). If a functional polymer is used as the chain-transfer agent, which has an active hydrogen, the acetal block copolymer, which shows characteristic properties, can be obtained.
Does a Magnetic Field Induce Optical Activity in Photochemical Reaction of 4-Methyl-2-quinolinecarbonitrile with Optically Active (S)-(+)-2-Phenylpropionic Acid ?
Authors: Fujiwara Yoshihisa , Tanaka Tomohiro , Ohtani Hokuto , Tanimoto Yoshifumi
Published: July 2006

The effect of a magnetic field on optical activity of a product was reinvestigated in photochemical reaction of 4-methyl-2-quinolinecarbonitrile with optically active (S)-(+)-2-phenylpropionic acid. The spectroscopic data show that the product, 4-methyl-2-(1-phenylethyl)quinoline, becomes racemic both in the presence and absence of a magnetic field (45 mT), indicating no induction of the optical activity by the magnetic field.
Synthesis of Tris(β-diketonato)indium from Metallic Indium and Bis(β-diketonato)copper
Authors: Wakeshima Ikuko , Watanabe Sazuku , Kijima Ichiro
Published: July 2006

The reaction between metallic indium and bis(β-diketonato)copper(II) in non-aqueous solution produced the corresponding indium chelate compounds of the type [In(dik)3], where Hdik denotes CH3COCH2COCH3 (Hacac), CH3COCH2COC6H5 (Hbzac), C6H5COCH2COC6H5(Hdbzm), or (CH3)3CCOCH2COC(CH3)3 (Hdpm). The [In(acac)3] was formed in high yield by the reactions using o-dichlorobenzene, decaline, or DMSO as solvent. The other indium chelate compounds were synthesized by reactions using DMSO as solvent.
Synthesis of 6-Amino-5,6-dideoxy-5-hyroxyphosphinyl-d-glucopyranose
Authors: Hanaya Tadashi , Fujii Yasushi , Yamamoto Hiroshi
Published: July 2006

The title sugar analogue (9) was conveniently synthesized from known 3-O-acetyl-5,6-dideoxy-5-dimethoxyphosphinyl-1,2-O-isopropylidene-6-nitro-α-d-glucofuranose in 4 steps via the 6-t-butoxycarbonylamino derivative. The structure of 9 was established by spectroscopy after conversion into the 6-acetamido-1,2,3,4-tetra-O-acetyl-5-methoxyphosphinyl derivatives.
Identification of Absolute Configuration of Tertiary Alcohols by Combination of Mosher's Method and Conformational Analysis
Authors: Izumi Shunsuke , Moriyoshi Hiroyuki , Hirata Toshifumi
Published: July 2006

Mosher's method for identification of the absolute configurations of secondary alcohols could be extended to that of tertiary alcohols, such as (1S,2S,5R)- and (1S,2R,5R)-pinan-2-ol, on the basis of its conformational analysis.
Effect of Methyl Substituents on the Double Bond Involved in the Formation of Tetrahydropyrans from Hydroxy Allylic Acetates
Authors: Nakata Masaya , Yasuda Minoru , Kawakita Jin
Published: July 2006

Substitutive cyclization of allylic acetates by an internal secondary hydroxyl group under acidic conditions to yield 2,6-disubstituted tetrahydropyrans has been investigated. The reaction is influenced by the substitution type of the double bond.
Syntheses and Properties of Ferrocenylethynyl Transition Metal Complexes of Platinum, Palladium, and Nickel
Authors: Onitsuka Kiyotaka , Tao Xin-Qung , Sonogashira Kenkichi
Published: July 2006

Square planar ferrocenylethynyl transition metal complexes M(C≡CFc)2(PR3)2 (M = Pt, Pd, Ni; Fc = (C5H4)Fe(C5H5)) were prepared by the reaction of MCl2(PR3)2 with ethynylferrocene in the presence of a CuI catalyst in diethylamine, and characterized by spectral analyses. An interaction between transition metals and an iron atom was studied by using electronic spectroscopy.
Violations of Cumulative Prospect Theory in Mixed Gambles with Moderate Probabilities
Authors: Baltussen Guido , Post Thierry , van Vliet Pim
Published: July 2006

In a classroom choice experiment with mixed gambles and moderate probabilities, we find severe violations of cumulative prospect theory (CPT) and of Markowitz stochastic dominance. Our results shed new light on the exchange between Levy and Levy (2002) and Wakker (2003) in this journal.
Timeshare Exchange Mechanisms
Authors: Wang Yu , Krishna Aradhna
Published: July 2006

This paper focuses on the timeshare industry, where members own timeshare “weeks” and can exchange these weeks among themselves without a medium of exchange (such as money). Timeshare exchanges allow for the weeks to be redistributed among members to better match their preferences and thus increase efficiency. As such, the problem falls within the domain of matching problems, which have recently gained much attention in academia. We demonstrate theoretically that the two major timeshare exchange mechanisms used currently (deposit-first mechanism and request-first mechanism) can cause efficiency loss. We propose an alternate exchange mechanism, the top trading cycles chains and spacebank (TTCCS) mechanism, and show that it can increase the efficiency of the timeshare exchange market because TTCCS is Pareto efficient, individually rational, and strategyproof. We test the three exchange mechanisms in laboratory experiments where we simulate exchange markets with networked “timeshare members.” The results of the experiments are robust across four different environments that we construct and strongly support our theory. The research focuses on an industry not studied earlier within academia and extends theoretical work on mechanism design to cases where supply of resources is dynamic, but resources can be stored.
Conducting R&D in Countries with Weak Intellectual Property Rights Protection
Authors: Zhao Minyuan
Published: July 2006

Multinational enterprises (MNEs) are increasingly conducting research and development (R&D) in countries such as China and India, where intellectual property rights (IPR) protection is still far from adequate. This paper examines this seemingly puzzling situation. I argue that weak IPR leads to low returns to innovation and underutilization of innovative talents; MNEs that possess alternative mechanisms for protecting their intellectual properties will therefore find it attractive to conduct R&D at those locations. A theoretical framework is developed to capture the interaction between firm strategy and the institutional environment. The empirical analysis on a sample of 1,567 U.S.-headquartered innovating firms finds results consistent with the hypotheses that (i) technologies developed in countries with weak IPR protection are used more internally, and (ii) technologies developed by firms with R&D in weak IPR countries show stronger internal linkages. The results suggest that firms may use internal organizations to substitute for inadequate external institutions. By doing so, they are able to take advantage of the arbitrage opportunities presented by the institutional gap across countries.
Outcome after surgery for fracture of the hip in patients aged over 95 years
Authors: Holt G. , Macdonald D. , Fraser M. , Reece A. T.
Published: July 2006

Despite the increase in numbers of the extreme elderly, little data is available regarding their outcome after surgery for fracture of the hip. We performed a prospective study of 50 patients aged 95 years and over who underwent this procedure. Outcome measures included morbidity, mortality, hospital stay, residential and walking status. Comparison was made with a control group of 200 consecutive patients aged less than 95 years who had a similar operation. The mortality at 28 and 120 days was higher (p = 0.005, p = 0.001) in the patients over 95 years. However, the one-year cumulative post-operative mortality was neither significantly different between the two groups (p = 0.229) nor from the standardised mortality rate for the age-matched population (p = 0.445). Predictors of mortality included the ASA grade, the number of comorbid medical conditions and active medical problems on admission. Patients over 95 were unlikely to recover their independence and at a mean follow-up of 29.3 months (12.1 to 48) 96% required permanent institutional care.
A kinematic comparison of fixed- and mobile-bearing knee replacements
Authors: Delport H. P. , Banks S. A. , De Schepper J. , Bellemans J.
Published: July 2006

Mobile-bearing posterior-stabilised knee replacements have been developed as an alternative to the standard fixed- and mobile-bearing designs. However, little is known about the in vivo kinematics of this new group of implants. We investigated 31 patients who had undergone a total knee replacement with a similar prosthetic design but with three different options: fixed-bearing posterior cruciate ligament-retaining, fixed-bearing posterior-stabilised and mobile-bearing posterior-stabilised. To do this we used a three-dimensional to two-dimensional model registration technique. Both the fixed- and mobile-bearing posterior-stabilised configurations used the same femoral component. We found that fixed-bearing posterior stabilised and mobile-bearing posterior-stabilised knee replacements demonstrated similar kinematic patterns, with consistent femoral roll-back during flexion. Mobile-bearing posterior-stabilised knee replacements demonstrated greater and more natural internal rotation of the tibia during flexion than fixed-bearing posterior-stabilised designs. Such rotation occurred at the interface between the insert and tibial tray for mobile-bearing posterior-stabilised designs. However, for fixed-bearing posterior-stabilised designs, rotation occurred at the proximal surface of the bearing. Posterior cruciate ligament-retaining knee replacements demonstrated paradoxical sliding forward of the femur.

We conclude that mobile-bearing posterior-stabilised knee replacements reproduce internal rotation of the tibia more closely during flexion than fixed-bearing posterior-stabilised designs. Furthermore, mobile-bearing posterior-stabilised knee replacements demonstrate a unidirectional movement which occurs at the upper and lower sides of the mobile insert. The femur moves in an anteroposterior direction on the upper surface of the insert, whereas the movement at the lower surface is pure rotation. Such unidirectional movement may lead to less wear when compared with the multidirectional movement seen in fixed-bearing posterior-stabilised knee replacements, and should be associated with more evenly applied cam-post stresses.
Hidden blood loss after surgery for hip fracture
Authors: Foss N. B. , Kehlet H.
Published: July 2006

Our aim was to determine the total blood loss associated with surgery for fracture of the hip and to identify risk factors for increased blood loss. We prospectively studied 546 patients with hip fracture. The total blood loss was calculated on the basis of the haemoglobin difference, the number of transfusions and the estimated blood volume. The hidden blood loss, in excess of that observed during surgery, varied from 547 ml (screws/ pins) to 1473 ml (intramedullary hip nail and screw) and was significantly associated with medical complications and increased hospital stay. The type of surgery, treatment with aspirin, intra-operative hypotension and gastro-intestinal bleeding or ulceration were all independent predictors of blood loss.

We conclude that total blood loss after surgery for hip fracture is much greater than that observed intra-operatively. Frequent post-operative measurements of haemoglobin are necessary to avoid anaemia.
Application of the polymerase chain reaction on formalin-fixed, paraffin-embedded tissue in the recognition of tuberculous osteomyelitis
Authors: Jambhekar N. A. , Kulkarni S. P. , Madur B. P. , Agarwal S. , Rajan M. G. R.
Published: July 2006

A retrospective series of 45 cases of chronic osteomyelitis collected over a period of 14 years was histologically classified into tuberculous osteomyelitis (25) and chronic non-granulomatous osteomyelitis (20). The tuberculous osteomyelitis group was divided into three subgroups: a) typical granulomas (13 cases); b) ill-defined granulomas (seven cases), and c) suspected granulomas (five cases). An in-house polymerase chain reaction amplifying the 245 bp nucleotide sequence, and capable of detecting 10 fg of DNA of Mycobacterium tuberculosis, was used on the DNA extracted from the paraffin blocks. The polymerase chain reaction was positive in 72% of cases (18) of tuberculous osteomyelitis, but when typical cases of tuberculous osteomyelitis with confirmed granulomas were considered (13), this increased to 84.6% (11). The chronic non-granulomatous osteomyelitis group gave positive polymerase chain reaction results in 20% of the cases (4).

Our preliminary study on tuberculous osteomyelitis shows that the polymerase chain reaction can be a very useful diagnostic tool, since a good correlation was seen between typical granulomas and polymerase chain reaction with a sensitivity of 84.6% and a specificity of 80%. In addition, our study shows that tuberculous osteomyelitis can be diagnosed in formalin-fixed paraffin-embedded tissues in the absence of typical granulomas.
Ankle arthrodesis for failed total ankle replacement
Authors: Hopgood P. , Kumar R. , Wood P. L. R.
Published: July 2006

Between 1999 and 2005, 23 failed total ankle replacements were converted to arthrodeses. Three surgical techniques were used: tibiotalar arthrodesis with screw fixation, tibiotalocalcaneal arthrodesis with screw fixation, and tibiotalocalcaneal arthrodesis with an intramedullary nail. As experience was gained, the benefits and problems became apparent. Successful bony union was seen in 17 of the 23 ankles. The complication rate was higher in ankles where the loosening had caused extensive destruction of the body of the talus, usually in rheumatoid arthritis. In this situation we recommend tibiotalocalcaneal arthrodesis with an intramedullary nail. This technique can also be used when there is severe arthritic change in the subtalar joint. Arthrodesis of the tibiotalar joint alone using compression screws was generally possible in osteoarthritis because the destruction of the body of the talus was less extensive. Tibiotalocalcaneal arthrodesis fusion with compression screws has not been successful in our experience.
The relationship between the orientation of the glenoid and tears of the rotator cuff
Authors: Kandemir U. , Allaire R. B. , Jolly J. T. , Debski R. E. , McMahon P. J.
Published: July 2006

Our aim was to determine the most repeatable three-dimensional measurement of glenoid orientation and to compare it between shoulders with intact and torn rotator cuffs. Our null hypothesis was that glenoid orientation in the scapulae of shoulders with a full-thickness tear of the rotator cuff was the same as that in shoulders with an intact rotator cuff.

We studied 24 shoulders in cadavers, 12 with an intact rotator cuff and 12 with a full-thickness tear. Two different observers used a three-dimensional digitising system to measure glenoid orientation in the scapular plane (ie glenoid inclination) using six different techniques. Glenoid version was also measured. The overall precision of the measurements revealed an error of less than 0.6°.

Intraobserver reliability (correlation coefficients of 0.990 and 0.984 for each observer) and interobserver reliability (correlation coefficient of 0.985) were highest for measurement of glenoid inclination based on the angle obtained from a line connecting the superior and inferior points of the glenoid and that connecting the most superior point of the glenoid and the most superior point on the body of the scapula. There were no differences in glenoid inclination (p = 0.34) or glenoid version (p = 0.12) in scapulae from shoulders with an intact rotator cuff and those with a full-thickness tear. Abnormal glenoid orientation was not present in shoulders with a torn rotator cuff.