bluuebunny/crossref_metadata_2025_split huggingface dataset:
Infrared Spectrum of Deoxyribonucleic Acid —Effects of Base Composition and of 15N-Substitution—
Authors: Tsuboi Masamichi , Shuto Katsuichi , Higuchi Shigesada 
Published: July 2006

Abstract
Infrared absorption spectra have been observed in the 4000–500 cm−1 region of deuterated and undeuterated films of deoxyribonucleic acids (DNA’s) obtained from Micrococcus lysodeikticus (guanine plus cytosine content or GC content 72%), from Bacille de Calmette-Guérin (GC 65%), from Pseudomonas aeruginosa (GC 65%, 15N-substituted), from calf thymus (GC 44%), and from Cancer borealis (GC 3%). Of the undeuterated DNA, 14 absorption bands have been assigned to the GC pair and 17 absorption bands to the adenine-thymine (AT) pair. Of the deuterated DNA, 19 absorption bands have been assigned to the GC pair and 16 to the AT pair. For 4 bands of undeuterated DNA and 13 bands of deuterated DNA, appreciable 15N isotopic shifts have been observed. A discussion has been given of a few of these bands on the basis of the observed 15N shift and some other data.
Rheological Properties of Hydrogels of Agar-agar. III. Stress Relaxation of Agarose Gels
Authors: Watase Mineo , Arakawa Kiyoshi 
Published: July 2006

Abstract
A stress relaxation experiment on hydrogels of agarose isolated from agar-agar was made by means of a chainomatic balance relaxometer for the purpose of investigating the mechanism of gelation. The measurements were made on the agarose gels of the concentration range from 1.2 to 2.0 wt%, and also on agar-agar gels for the comparison, at various temperatures from 25 to 55°C. The relaxation curves obtained were represented approximately by a mechanical model consisting of three Maxwell models in parallel. The apparent activation energy, ΔH, which was calculated from the temperature dependence of the longest relaxation time, τ1 was about 5 kcal/mol for all gels treated in this study, which was nearly the same magnitude as that for agar-agar gels. It was observed in the curves obtained that the relaxation curves for agarose gels had quite similar characteristics to those for agar-agar gels of the same concentration and was observed that the total instantaneous modulus of the former gels amounted to about 80% of that of the latter gels. From these results it may be concluded that agarose is a main constituent in the network structure in agar-agar gels and that the hydrogen bonding plays a major role in the agar-agar gels as well as in the agarose gels.
The Bromination of Tris(3-phenyl-2,4-pentanediono)cobalt (III)
Authors: Murakami Yukito , Nakamura Katsuyuki 
Published: July 2006

Abstract
Tris(3-phenyl-2,4-pentanediono)cobalt(III) has been treated with three kinds of bromination reagents; bromine in the presence of pyridine, pyridine perbromide, and N-bromosuccinimide. Components of the product species have been detected by means of thinlayer chromatography and fractionated by liquid-chromatography. The characterization of bromination products has been performed by the aid of infrared and nuclear magnetic resonance spectroscopy. The bromination has taken place with the chelate ring remaining intact, and converted methyl groups in the coordinated ligands to bromomethyl. The cleavage of coordinate bonds, which has occurred afterward, has resulted in the formation of a metal-absent brominated ligand. Among various bromination products, the one with lowest bromination degree (monobrominated chelate) has been fully characterized in accordance with the experimental facts: elemental analysis, the appearance of a new infrared band at 1248 cm−1 which is attributable to CH2 wagging vibration of the CH2Br group, and two doublet NMR peaks at 3.55, 3.69, 3.94 and 4.09 in δ-value which are due to nonequivalent protons of the CH2Br group. Reaction mechanism has been discussed in terms of electrophilic substitution process.
Intramolecular Hydrogen Bonds. XII. The Dipolar-field and the Hydrogen-bonding Effects of the Hydroxyl Group on the Carbonyl Frequencies of Aliphatic Hydroxy-carboxylates
Authors: Mori Nobuo , Asano Yuzuru , Tsuzuki Yojiro 
Published: July 2006

Abstract
The infrared carbonyl-stretching absorption bands of several methoxy- and hydroxyalkanoates have been measured in dilute carbon tetrachloride solutions, and their frequency shifts from the normal bands of ethyl alkanoates have been explained in terms of the dipolar-field and the hydrogen-bonding effects of the substituents. Further, as regards the direction of hydrogen bonding, the spectral data of the hydroxy-esters lead to essentially the same conclusion as that based on their hydroxyl spectra. However, the magnitudes of the carbonyl-frequency shifts due to hydrogen bonding can not be related to those of the corresponding hydroxyl shifts.
Condensation Reaction of Ferrocene with Carbonyl Compounds
Authors: Shiga Mikio , Motoyama Izumi , Hata Kazuo 
Published: July 2006

Abstract
The condensation reactions of ferrocene with various ketones and with trichloroacetaldehyde in the presence of aluminum chloride were investigated. The formation of carbinol (7) as an intermediate was postulated in these reactions. In the reaction of acetone with ferrocene, the intermediate carbinol underwent further condensation with other ferrocene molecules to give oligomers (9). On the other hand, in the cases of methyl ethyl ketone, acetophenone, propiophenone, cyclohexanone, and trichloroacetaldehyde, the condensation reactions produced olefinic compounds via the intermediate carbinols. The intermediate carbinol was isolated together with the olefin in the reaction with trichloroacetaldehyde.
Hydrolysis of Uranium Monocarbide and Oxidation Potentials
Authors: Hori Yoshio , Mukaibo Takashi 
Published: July 2006

Abstract
The hydrolysis of UC with 1 n H2SO4 was carried out in the presence of various oxidants at 80°C. The amount of gaseous products was measured by means of a gas chromatograph; the dissolved, carbon-containing compounds, and the insoluble residues produced in the reaction were analyzed for carbon. Analyses of the uranium and oxidants consumed were also made by volumetric and gravimetric methods. The results may be summarized : (1) The hydrolysis of UC with 1 n H2SO4 proceeds by an electro-chemical mechanism. (2) The hydrolysis products fundamentally depend upon the oxidation potential of the oxidants in the solution. (3) The oxidation potential at which the hydrolysis of UC with 1 n H2SO4 proceeds can be explained in terms of the partial ionic character of UC. (4) The application of this experimental method to other carbides would serve to clarify the chemical reaction and the bond character of the carbides.
ASMO-SCF-CI Calculation on the Electronic Structures of the Bases of Nucleic Acids with Special Emphasis on the Configuration Interaction
Authors: Fujita Hiroko , Imamura Akira , Nagata Chikayoshi 
Published: July 2006

Abstract
The calculation was carried out on the electronic structures of the bases of nucleic acids by means of semi-empirical self-consistent field configuration interaction (SCF-CI) method taking into account of the CI calculation. The effects of mixed configurations, e.g., doubly excited ones, on the transition energies and oscillator strengths, were remarkable. On the other hand, the effects on the direction of the transition moments and the π–electron densities were small. The more configurations were involved, the better the calculated data agreed with the experimental result, but the change of the calculated values with increasing number of configurations from twenty to thirty was small. The agreement between the calculated singlet transition energies and the observed ones obtained by the vapor spectra of the bases was satisfactory, when twenty or thirty configurations including doubly excited ones were considered. The direction of the transition moment calculated by the present authors for thymine agreed well with the experimental result by Stewart and Davidson. For adenine, the calculated direction of transition moment of the main band was polarized parallel to long-axis and it coincided not with the result obtained by Stewart and Davidson, but with that proposed by Mason. Variation of the core resonance integral exerted the influence on the electronic structures, and K in Eq. (1), viz., −0.49 was better than −0.431 when doubly excited configurations were taken into calculation.
Kinetics of Multidentate Ligand Substitution Reaction. III. Substitution Reactions of BT with Cobalt(II) and Nickel(II) Chelates of N-(2-Hydroxyethyl)-ethylenediamine-N,N′,N′-triacetic Acid and 2,2′-Ethylenedioxybis[ethyliminodi(acetic acid)]
Authors: Kodama Mutsuo , Sasaki Chifumi , Noda Tomohiko 
Published: July 2006

Abstract
BT can displace EDTA-OH and GEDTA from their cobalt(II) and nickel(II) chelate as in the case of the substitution reaction of BT with cobalt(II)-EDTA chelate or nickel(II)-EDTA chelate. In this paper, kinetics of the substitution reactions of BT with cobalt(II)- and nickel(II)-chelates of EDTA-OH and of GEDTA was studied spectrophotometrically. All substitution reactions were found to be first-order in BT and first-order in metal(II)-chelate of EDTA-OH or GEDTA, and to proceed through two simultaneous reaction paths analogous to those proposed for the substitution reaction of BT with cobalt(II)-EDTA chelate. Although EDTA-OH differs from EDTA by the presence of a hydroxyethyl group in place of one acetate group, its metal(II) chelate behaves in a nearly identical manner with EDTA chelate in the substitution reaction and the cleavage of the metal-nitrogen bond of the glycinate group is considered to be the probable rate-determining step. The substitution reactions of BT with GEDTA chelates are considered to be more favored thermodynamically over the reactions of EDTA-OH chelates, but were found to be less favored kinetically. This fact may suggest that the geometrical structure of metal(II)-GEDTA plays an important role in determining the rate of the substitution reaction of GEDTA.
Studies of the Grinding of Condensed Phosphates. IV. Grinding of Sodium Trimetaphosphate at Low Pressure
Authors: Motooka Itaru , Hashizume Genzo , Kobayashi Masamitsu 
Published: July 2006

Abstract
The change in sodium trimetaphosphate by grinding at low pressure was examined by the X-ray diffraction method and paper chromatography. The crystalline sodium trimetaphosphate became amorphous more rapidly when ground at low pressure than in dry air or nitrogen gas, and in these cases the chain phosphates higher than triphosphate were produced in addition to ortho-, pyro- and tri-phosphates.
Syntheses and Properties of Some Tetrabromobis(dithioacetylacetonato)Complexes
Authors: Furuhashi Akiko , Takeuchi Toshio , Ouchi Akira 
Published: July 2006

Abstract
Some compounds of type M(Lss)2Br4, where M is Mn(II), Fe(II), Co(II), Cu(II), Zn(II) and Cd(II) and HLss are dithioacetylacetone, were obtained by passing hydrogen bromide, adding bromine and passing hydrogen sulfide through an ethanolic solution containing an anhydrous metal bromide and acetylacetone. Such compounds, which seem to be isostructural with tetrachlorobis-(dithioacetylacetonato)iron(II), are stable. They are all of high spin, and their infrared spectra show characteristic bands at about 1200, 1000 and 860 cm−1. CuI(Lss)2Br3 was also obtained from cupric bromide by the same method without using bromine, but from cupric chloride, an isostructural complex was not obtained but [Cu(C5H8S2)Cl]n. Electronic spectra are also shown and discussed.
Studies on Coprecipited Phases in the Calcium-Gadolinium Oxalate System
Authors: Chi Hsiu , Nagashima Kozo 
Published: July 2006

Abstract
Calcium oxalate is often used as a carrier for precipitating rare earth elements. Gadolinium was chosen as a rare earth element and X-ray powder diffractometry used for the identification of coprecipitated solids. The X-ray lattice spacings are tabulated for each of the coprecipitates of varying composition in the calcium-gadolinium oxalate system. From the spacings, the following facts were obtained: (1) The uptake mechanisms of gadolinium in calcium oxalate, and calcium in gadolinium oxalate are completely due to the formation of solid solutions. (2) Several new solid solution phases were formed. (3) When the gadolinium to calcium ratio is proper, precipitates having a weddellite structure, which is not obtained in usual analytical procedures, are formed.
Structure and Properties of the Condensation Product of 2-Amino-3-ethoxycarbonyl-1-azaazulene and Formamide
Authors: Nozoe Tetsuo , Seto Shuichi , Toda Takashi 
Published: July 2006

Abstract
The structure of the condensation product of 2-amino-3-ethoxycarbonyl-1-azaazulene and formamide is proved not to be the expected cyclohepta[2,3]pyrrolo[5,4-d]pyrimidine derivative, but 5,6-pentamethylene-7H-pyrrolo[2,3-d]pyrimidin-4(3H)-one. The chemical properties of the obtained pyrrolo-pyrimidine are investigated, and then the tautomerism of the above compound is discussed.
Polar Conjugative Effect of Aryldithia Group on the Dissociation and Ultraviolet Spectra of Substituted Phenols
Authors: Oae Shigeru , Yoshihara Masakuni 
Published: July 2006

Abstract
A few substituted aryldithiaphenols have been synthesized and their acid dissociations, NMR chemical shifts and UV spectra have been determined. The relatively stronger acidic nature of p-aryldithiaphenols over that of the meta-isomers is interpreted as being caused by the 3d-orbital resonance effect of the aryldithia group.
The Formation and Reactions of α-Keto Sulfoxide
Authors: Kumamoto Takanobu , Mukaiyama Teruaki 
Published: July 2006

Abstract
The reactions of α-keto sulfoxide, produced by the oxidation of thiolester, were studied. It was established that the oxidation of S-ethyl thiobenzoate with N-bromosuccinimide and isopropyl alcohol afforded benzoyl ethyl sulfoxide. Similarly, butyryl ethyl sulfoxide was produced by the oxidation of S-ethyl thiobutyrate with iodosobenzene. α-Keto sulfoxide, produced by the above-mentioned oxidations, reacts with alcohols, phenols, amines or sodium carboxylates to afford acylated products such as esters, amides or carboxylic anhydrides in good yields.
Ring-butylamination of Toluquinone: Isolation of Products by TLC and an Observation of Their Reaction Course on the Basis of Molecular Reactivity Index
Authors: Kumanotani Ju , Kagawa Fumio , Hikosaka Aizo , Sugita Kazuyuki 
Published: July 2006

Abstract
The ring-butylamination of toluquinone with n-butyl-amine was carried out in a chloroform or ethanolic solution at room temperature or at 25.0°C with various molar ratios of the quinone to the amine (designated as Q/A). For the successful separation of each product, TLC was applied, while polarography was used for following the change in the composition of the reacting mixture as well as for measuring the amount of the amino-quinone separated from the reacting mixture by TLC. In the butylamination of toluquinone with excess butylamine (Q/A: 1/5) for 10 hr, the major products were 3,6-bis-(n-butylamino)-toluquinone (32%) and 2,5-bis(n-butylamino)-p-benzoquinone (8%), accompanied by a relatively large amount of unknown by-products: with a Q/A of 2/1 for 2 hr, the major products were 3- and 4-n-butylamino-toluquinone (17% and 21%) and 3,6-bis(n-butylamino)-toluquinone (3.3%) together with toluhydroquinone (47%). The quantitative formation of 3,6-bis(n-butylamino)-toluquinone from 3-n-butylamino-toluquinone or the formation of 2,5-bis(n-butylamino)-p-benzoquinone (34%) and 3,6-bis-(n-butylamino)-toluquinone (1%) from 4-n-butylamino-toluquinone was also found (Q/A: 1/4, 3 hr or 13 hr), where a faster reaction was found for the 3-isomer than for the 4-isomer under the present conditions. The pathway of the formation of each product was discussed on the basis of the calculated reactivity index of toluquinone or its butylaminated toluquinone isomers toward the amine-attacking.
Photochemical Rearrangement of Azoxybenzene to 2-Hydroxyazobenzene and cis-trans Isomerization
Authors: Tanikaga Rikuhei 
Published: July 2006

Abstract
The photochemical oxygen migration and cis-trans isomerization of azoxybenzene have been investigated. The direct irradiation of trans-azoxybenzene leads to both rearrangement to 2-hydroxyazobenzene and cis-trans isomerization, whose rate is faster in a polar protic solvent and is never affected by a quencher. Direct irradiation does not afford any azobenzene formed from an excited triplet state of azoxybenzene. On the basis of these observations, the author proposes a mechanism in which 2-hydroxyazobenzene and cis-azoxybenzene are formed directly from an excited singlet state of trans-azoxybenzene. This mechanism is analogous to that for the photochemical rearrangement of nitrone to oxaziridine. Nitro- or dimethylamino-substituted azoxybenzene undergoes neither photochemical rearrangement nor cis-trans isomerization. Oxygen migration is not sterically hindered by a substituent in the 3-position of azoxybenzene.
Medium-Sized Cyclophanes. VI. High-Temperature NMR Spectra of [2.2]Metacyclophane and Optical Resolution of 4,14-Disubstituted Derivatives
Authors: Sato Takeo , Akabori Sadatoshi , Kainosho Masatsune , Hata Kazuo 
Published: July 2006

Abstract
The NMR spectra of [2.2]metacyclophane have been shown to be held unchanged over a wide range of temperature, ca. −80 to 190°C, indicating that the ten-membered ring system undergoes no inversion and is frozen in a chair conformation. It may, then, be expected that suitably substituted derivatives of [2.2]metacyclophane would become disymmetric due to restricted inversion; such was proved to be the case by carrying out the optical resolution of the 4, 14-di-substituted derivatives. The 4,14-dimethyl derivative was resolved by means of a complex formation with Newman’s reagent, [α]57826=−3.4 and +4.2°. 4,14-Dicarboxylic acid was also resolved by converting it to the quinine salt, [α]d22=+5.0°.
Oxygen Oxidation of Ferrous Ions Induced by Chelation
Authors: Kurimura Yoshimi , Ochiai Ryoji , Matsuura Niro 
Published: July 2006

Abstract
The oxidation of ferrous ions by dissolved oxygen in aqueous solutions in the presence of such chelating agents as EDTA, DTPA, EDTAOH, EDTP, CyDTA and NTA was studied spectrophotometrically. The rate equation for the oxidation reaction is:
d[Fe^III]/dt=4k_p[Fe^IIHZ][O_2]+4k_n[Fe^IIZ][O_2]
where kp is the rate constant for the (1) reaction; kn, the rate constant for the (2) reaction; FeIIHZ, protonated chelate, and FeIIZ, the normal chelate.
&Fe^IIHZ+O_2\xrightarrowk_pFe^IIIZ+HO_2 \labeleq1
&Fe^IIZ+O_2\xrightarrowk_nFe^IIIZ+O_2^-\labeleq2
The linear relationship between log k and log Rf shown by Eq. (3), was obtained from all the experimental results except for those on the EDTPA and CyDTA systems:
logk=0.92+0.13logR_f\labeleq3
In Eq. (3), k is 4kp and Rf is KFeIIIL⁄KFeIIHL, for the protonated chelate, while k is 4kn and Rf is KFeIIIL⁄KFeIIL for the normal chelate. In the cases of the DTPA and CyDTA systems, a deviation from the straight line was observed. This can be explained by steric hindrance of the oxygen attack by these chelates.
An Energetic Consideration of the Monomer Reactivity in Catalytic Polymerization
Authors: Kagiya Tsutomu , Sumida Yūzō , Nakata Tetsuya 
Published: July 2006

Abstract
The elementary processes constituting the polymerization reaction are energetically considered, and the relation between the activation energy of each process and the structures of reagents or the kind of solvents is theoretically discussed. The solvation energy of ion has been evaluated with the ionization potential of anion or the electron affinity of cation, and the ionization potential or the electron affinity of the growing radical with that of the corresponding monomer. The energy of the highest occupied (εho=α+λhoβ) or the lowest vacant (εlv=α–ηlvβ) π level of the monomer has been calculated, and the π bond dissociation energy has been evaluated with the summation (λho+ηlv). On the basis of these considerations, the monomer reactivity in catalytic polymerization can be compared with the relative magnitude of the electronic natures of monomer and components of catalyst, i. e., ionization potential or electron affinity.
Nuclear Magnetic Double-resonance Study of the Hindered Internal Rotation in Formamide
Authors: Kamei Hirotake 
Published: July 2006

Abstract
The nitrogen-14 quadrupole relaxation broadening effect on the proton spectrum of formamide was eliminated by a 1H–{14N} double resonance technique. The completely-decoupled proton spectra of formamide in the neat liquid and in acetone, dioxane, and water solutions were observed at several temperatures. The spectra observed at room temperature were analyzed on the basis of an ABC system, while the spectra at higher temperatures (∼100°C) were analyzed on the basis of an AB2 system. From the changes in the resonance lines of the formyl proton with the temperature, the values of the activation energy for the hindered internal rotation about the C–N bond, Earot, and for the intermolecular proton exchange involving the amine protons, Eaex, were obtained. It has been found that the hydrogen-bond formation on the carbonyl oxygen of formamide increases the Earot value and the magnitude of the vicinal coupling constants, while it decreases the magnitude of the geminal coupling constant.
Photochemistry of Acetanilide. I. Quantum Yields of the Rearrangement and Benzene Photosensitized Reaction
Authors: Shizuka Haruo , Tanaka Ikuzo 
Published: July 2006

Abstract
The photochemical rearrangement of acetanilide under 2537 Å irradiation has been studied by spectrophotometry. The quantum yield of the rearrangement in cyclohexane solution was independent of the irradiation time, concentration of acetanilide, presence of oxygen and light intensity. It was found that electronic energy transfer from the electronically excited benzene to acetanilide occurred in the mixed solution, and the transfer mechanism was explained by singlet-singlet nonradiative energy transfer. It was observed that the energy transfer rate constant was about 22 times greater than that predicted by diffusion theory (the transfer rate constant, k3=1.45×1011 l·mol−1·sec−1). From these studies, it is proposed that the rearrangement of acetanilide is an introamolecular reaction and does not occur from the triplet state but from the lowest singlet excited state.
Synthetic Inorganic Ion-exchange Materials. XII. Some Observation on Surface Structure and Cation-exchange Behaviour of Three Different Antimonic Acids
Authors: Abe Mitsuo , Ito Takuji 
Published: July 2006

Abstract
The cation-exchange behaviour and surface functionality of three different antimonic acids, amorphous, glassy and crystalline, were studied by thermogravimetric measurement, infrared absorption spectrometry and change in uptake of potassium ions upon heating. The ion-exchange capacities of the amorphous and glassy antimonic acids decrease with the loss of chemically bonded water. In contrast, the capacities of the crystalline acid heated within 200°C rarely change because of the loss of the interstitial (free) water and no drastic change occurs in the surface structure of the crystal. The crystalline acid with free water removed adsorbs moisture upon exposure to the atomsphere at room temperature. Upon heating above 300°C, the tenaciously bonded water was removed and the cation-exchange capacity decreased simultaneously. The infrared absorption spectra indicated that the surface functionality of the crystalline acid, similar to that of crystalline sodium antimonate Na[Sb(OH)6], is different from those of the amorphous and glassy acids. It seems that chemically bonded water in the crystalline acid is tenaciously combined as Sb-OH.