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This paper suggests an IoT device utilization for skid suppression for work vehicles in the framework of Hybrid Twin and the performances of IoT utilization are experimentally evaluated. In the autonomous driving of work vehicles, stuck state or lock state should be avoided because it is very difficult to escape from these states autonomously. First of all, a state transition diagram consisting of grip, skid, stuck and lock states is configured and a skid ratio is newly defined to measure the degree of skid. Then, a three-stage skid suppression method is suggested based on skid ratio and a controlling system is implemented by using MATLAB/Simulink. Using an actual snow blower, an IoT device with some filtering processes is incorporated and the three-stage skid suppression method is applied. The experimental results show that the suggested approach is feasible but not a three-stage but a two-stage skid suppression method is likely to be efficient because of insufficient noise reduction. As future work, the noise reduction should be improved and the skid suppression method should be implemented in a Hybrid Twin approach.

The photoreaction mechanism of 3-chloro-2-hydroxypyridine isolated in a low-temperature argon matrix was investigated by IR spectroscopy and density functional theory (DFT) calculations. Two tautomeric forms, keto and enol I, with an intramolecular N⋯H–O hydrogen bond, existed in the matrix before UV irradiation. Tautomerization from the keto form to enol I occurred completely upon the first UV irradiation ( λ ≥ 300 nm), while the second light irradiation ( λ ≥ 250 nm) induced the reverse tautomerization from enol I to the keto form as well as photodissociation to yield a five-membered-ring ketene, 2 H -pyrrol-2-ylidenemethanone, and HCl. The latter is similar to the photolysis of 2-chlorophenol to yield its corresponding five-membered-ring ketene by Wolff rearrangement after dissociation of HCl by UV irradiation. Kinetic analysis indicates the existence of a short-lifetime precursor, which is expected to be the less stable enol tautomer with an intramolecular Cl⋯H–O hydrogen bond. A trace of the intermediate was spectroscopically detected only during UV irradiation.

Hydrogen bonding is one of the exciting and interesting research themes because it plays important roles in biomolecules, plant cells, and so on. Here we report hydrogen-bonded complexes among the photodecomposition products of thiazole, being studied by a joint use of infrared (IR) spectroscopy and density-functional-theory (DFT) calculations. Three types of hydrogen-bonded complexes of ethynethiol (HS C CH) and hydrogen cyanide (HC N), which are photodecomposed by two cleavages of the NC–SC and CN–CC single bonds of thiazole in argon matrices, have been identified by comparison of the observed IR spectra with the corresponding calculated spectral patterns. In addition, another complex with weak interaction between S atom and HC N, which are photoproduced by cleavages of the three single bonds of thiazole, is detected by comparison with the wavenumbers previously reported in literature. The reaction mechanisms to form these complexes are discussed based on the analysis of IR spectra and the DFT calculations.

Photoinduced reversible intramolecular hydrogen-atom migration between 9H-fluorene and 1H-fluorene isolated in an Ar matrix is found by FTIR spectroscopy with an aid of DFT calculation. The forward isomerization from 9H-fluorene to 1H-fluorene occurs upon UV irradiation (λ ≥ 295 nm), while the backward isomerization occurs upon λ ≥ 320 nm light irradiation. The less stable isomer, 1H-fluorene, is identified by comparison of the measured IR spectrum with the corresponding simulated spectral pattern obtained at the B3LYP/6-31++G(d,p) level. In addition, an IR spectrum of 9H-fluorene in the T1 state is measured during UV irradiation (λ ≥ 275 nm).

The photoreactions of molecular complexes composed of O3 and three 5-membered heterocyclic compounds, tetrahydrothiophene (THT), pyrrolidine (PyD), and thiazolidine (TAD), are systematically invest...

A visible-light-induced reaction of an O3-trimethylamine (TMA) complex isolated in low-temperature noble-gas matrices is investigated by infrared (IR) and visible absorption spectroscopies using the DFT calculation. The complex isolated in a Ne matrix yields trimethylamine-N-oxide (TMAO) upon irradiation (λ ≥ 800 nm) by dissociation of O3. When the wavelength of radiation is changed to λ = 455 nm, two stable conformers of dimethylaminomethanol (DMAM) are recognized besides TMAO. In an Ar matrix, DMAM and not TMAO is mainly produced upon λ = 455 nm irradiation. The photoreaction mechanism of the O3-TMA complex with a single collision reaction between O(3P) and TMA in the gas phase to produce OH and CH2N(CH3)2 radicals is discussed.

Since acenaphthene isolated in an Ar matrix at 15 K emits green-yellow phosphorescence for ∼10 s after stopping UV-light irradiation, its transient IR spectrum is expected to be measured with an FTIR spectrometer during UV irradiation. The transient spectrum observed is found to be consistent with the simulated spectrum of acenaphthene in the lowest electronically excited triplet (T1) state calculated at the B3LYP/6–31++G(d,p) level. The spectral pattern obtained using the B3LYP functional, which is the most popular DFT hybrid functional, reproduces the observed spectrum more satisfactorily than that obtained using the recently proposed M06-2x functional, although the optimized geometrical parameters in the both calculations are not so different from each other. The IR-band assignments of the T1 state and the structural changes from the S0 state to the T1 state are discussed based on the results of B3LYP calculation.

Photoreaction of molecular complex composed of ozone and dimethylamine is investigated by matrix-isolation IR and UV–visible spectroscopies. The UV–visible spectrum of the molecular complex isolated in an Ar matrix shows two broad bands in the region between 400 and 700 nm. Upon red-light irradiation (λ ≥ 680 nm), dimethylamine-N-oxide is produced by intermolecular oxygen-atom transfer from O3 to the lone pair on the nitrogen atom of dimethylamine. Dimethylamine-N-oxide isomerizes to N,N-dimethylhydroxylamine by intramolecular hydrogen-atom migration upon the second light irradiation (λ ≥ 385 nm). The both photoproducts are identified by the DFT calculation at the B3LYP/6-31++G(d,p) level.

The photoreactions of 2-chlorothiophenol are investigated using matrix-isolation IR spectroscopy combined with density functional theory calculation at the B3LYP/6-311++G(3df,3pd) level. In a Ne matrix, 2,4-cyclopentadien-1-ylidenemethanethione, a five-membered-ring thioketene compound, is identified as the major photoproduct of a reaction similar to Wolff rearrangement. The reaction intermediate is spectroscopically detected as benzothiirene, which is produced from the reactant under UV (λ ≥ 275 nm) irradiation and is then converted to the thioketene under λ ≥ 325 nm irradiation. Moreover, the complex of benzothiirene and HCl changes into 4-chloro-2,5-cyclohexadiene-1-thione under irradiation at λ ≥ 325 nm. By contrast, UV irradiation of 2-chlorothiophenol in an Ar matrix yields primarily 4-chloro-2,5-cyclohexadiene-1-thione via its isomer 2-chloro-2,4-cyclohexadiene-1-thione.

Thermoluminescence spectra of gamma-irradiated shells of oysters, scallops, mussels, littleneck clams, and freshwater clams are measured with a multichannel Fourier-transform luminescence spectrometer. Oysters, scallops, and mussels isothermally heated at 200 °C show strong luminescence due to the electronic transition of Mn2+, which is included as an impurity in shells and excited to a metastable state by gamma-ray irradiation. Littleneck clams and freshwater clams show very weak thermoluminescence under the same experimental conditions and show strong thermoluminescence owing to phase transition when they are heated at 450 °C before gamma-ray irradiation. The phase transition of the crystal structures from aragonite to calcite is monitored by infrared spectroscopy.

Reaction mechanisms of nitrene, one of the most famous biradicals, have been frequently studied, and many spectral data have been obtained so far. In the present study, the experimental IR spectra of triplet 8-amino-1-naphthylnitrene (3ANN), a triplet diimine biradical 1,8-dihydro-1,8-naphthalenediimine (3DND), and 1,2-dihydrobenz[cd]indazole (DBI), which are produced in the UV photolysis of 1,8-diaminonaphthalene in an Ar matrix and identified by a combination method of IR spectroscopy and DFT quantum chemical calculations, are first reported. 3ANN is found to change to DBI by hydrogen-atom migration with bond making between the two nitrogen atoms upon visible-light irradiation (λ > 580 nm) with its backward reaction caused by 350 nm irradiation. In addition, 3ANN isomerizes to 3DND by 700 nm irradiation, while its backward reaction occurs upon 500 nm irradiation. The wavelength dependences of these photoisomerizations are explained in terms of their electronic transition energies estimated by time-depen...

UV-induced photoreactions of thiazole isolated in low-temperature argon matrices have been investigated by a joint use of infrared spectroscopy and density-functional-theory calculations. Photoproducts have been identified by comparison of the observed infrared spectra with the corresponding calculated spectral patterns, leading to the conclusion that undetected open-chain molecules, syn-2-isocyanoethenethiol (CN–CHCH–SH) and 2-isocyanothiirane, are initially produced by cleavage of the CS–CN bond with hydrogen-atom migration, when the matrix samples are exposed to UV radiation coming from a super high-pressure mercury lamp for 3 min. In the secondary photolysis, syn-2-isocyanoethenethiol and 2-isocyanothiirane change to another unknown molecule, 2-isocyanoethanethial (CN–CH2–CHS), by hydrogen-atom migration with generation of the CS double bond. These photoreaction pathways are supported by kinetic analysis of the absorbance changes of IR bands against irradiation time. We have also found that HCN and the ˙CHCH–S˙ biradical are photodecomposed from thiazole by cleavage of the CN–CC bond following the cleavage of the CS–CN bond, where the hydrogen atom on the center carbon atom of ˙CHCH–S˙ immediately migrates to the end carbon atom to form CH2CS or to the sulfur atom to form HCC–SH. In addition, weak bands of the species of interest in astrophysics and astrochemistry such as HCCH, NC–SH, HNCS, HCNS, and the ˙CN radical are detected, but the photoconversion from thiazole to isothiazole or Dewar thiazole is not found. The ring-opening photoreaction, photoisomerization and photodecomposition pathways of thiazole isolated in low-temperature argon matrices are discussed comprehensively.

This paper describes a co-simulator simulating interactions between electric power system and motor drive system in an EV. By using the developed co-simulator, the state-of-charge behaviors of battery with respect to motor drive and generative brake are obtained. In the experiments, the co-simulation is used to verify the design of actual micro EV and obtained results are useful for determining the design parameters of EV.

Multiscale structures of anisotropic nanoparticles up to macroscopic scales are important in order to produce practical materials through nanotechnology. As an example of such structures, hierarchical organization of colloidal liquid crystals of niobium oxide nanosheets yields stripe textures observable by naked eyes. The stripes are generated by the growth of liquid crystalline domains (tactoids) and the alignment of the tactoids under an electric field and gravity applied in the directions orthogonal to each other. The nanosheets forming the tactoids are unidirectionally aligned along the flow induced by gravity, and the aligned tactoids are stretched to be connected each other to form the stripes. Time evolution of the stripes indicates that they are generated during the settlement of the nanosheets. The nanosheets are debundled with the settlement, and thus the stripes are gradually degenerated during the settlement. Larger tactoids cause faster nanosheet settlement and stripe degeneration. The electric field applied orthogonally to gravity has roles of pinning the nanosheets to slow down their settlement and retains the stripes for several hours.

In order to elucidate the mechanism of degradation of γ-irradiated polytetrafluoroethylene (PTFE), gases evolved by isothermal heating under vacuum were trapped in low-temperature argon matrices. Infrared spectra of the evolved gases were assigned to COF2 and CF4 by comparison with the corresponding literatures. Kinetic analyses of the IR absorbance and chemiluminescence intensity changes against heating time were carried out to determine the rate constants of the thermal reactions, showing that CF4 was produced more rapidly than COF2. By comparison between the rate constants obtained by infrared spectroscopy and chemiluminescence spectroscopy, we propose a new thermal reaction mechanism of γ-irradiated PTFE at the molecular level. Thermal reaction mechanism of γ-irradiated polytetrafluoroethylene (PTFE) is elucidated at the molecular level by kinetic analysis, where a new multichannel Fourier-transform chemiluminescence spectrometer was used.

The chemiluminescence spectra of styrene-butadiene and acrylonitrile-butadiene rubbers isothermally heated in the range between room temperature and 200 °C were measured with a multichannel Fourier-transform chemiluminescence spectrometer. The observed spectra were analyzed by a least-squares fit using a Gaussian function to determine the peak intensity and the peak wavelength of emission bands. It was found that the peak wavelength of acrylonitrile-butadiene rubbers was slightly longer than that of styrene-butadiene rubbers due to the influence of the nitrile groups. The peak intensity of chemiluminescence from styrene-butadiene rubbers decreased with the styrene content, while that from hydrogenated acrylonitrile-butadiene rubbers increased with the iodine value. From these experimental results, it is concluded that the content of double bonds in the butadiene units in rubbers is measurable by chemiluminescence spectral analysis.

Conformational changes of 2-pyridinecarboxylic acid (2-picolinic acid) upon UV irradiation have been investigated by low-temperature matrix-isolation infrared spectroscopy. Only one conformer having an intramolecular hydrogen bond of COOH⋯N in the pyridine ring is found to exist in argon matrices after deposition before UV irradiation, in contrast to a reported feature in the CCl 4 solution. The hydrogen bond is broken by UV irradiation, resulting in two less stable conformers; one increases immediately at the early irradiation stage while the other increases slowly during the prolonged irradiation time. The conformations around the OC OH and C COOH bonds of the photoproducts are identified by assignments of the IR bands measured in an argon matrix with an aid of the density-functional-theory calculation. The proposed photoreaction pathways of the conformational changes based on this observation are supported by a kinetic analysis of the IR absorbance changes with the reactants and the photoproducts against the irradiation time.

Temperature dependence of the time evolution of chemiluminescence intensity from γ -irradiated polytetrafluoroethylene was examined by heating isothermally in the range of 150 and 200 °C. Kinetic analysis was carried out to estimate the rate constants, from which the dissociation energy of the O O bond in the fluoroperoxide group was determined to be 97 ± 4 kJ mol −1 , being consistent with the corresponding value for small fluorocarbon model systems obtained by quantum chemical calculations. This strongly supports the emission mechanism [ CF(OOF) CF 2 → CO CF 2 + OF 2 + hν ] proposed in our previous paper to explain chemiluminescence from the γ -irradiated polytetrafluoroethylene.

Thermal chemiluminescence spectra of polytetrafluoroethylene powder irradiated by γ rays in air at room temperature were measured with a multichannel Fourier-transform chemiluminescence spectrometer. The luminescence appeared immediately after heating the irradiated samples at 160, 180 and 200 °C in dry air and in N 2 and then disappeared within a few minutes, whereas virgin samples showed no luminescence. The lifetime of luminescence decreased as the heating temperature increased, but the total amount of luminescence at each temperature was nearly constant. From this observation an emission mechanism was derived with the aid of ESR and IR spectroscopy.

Photoreaction pathways of salicylic acid have been investigated by the low-temperature matrix-isolation infrared spectroscopy with an aid of the density-functional-theory calculations. Only the most stable E form existed in an argon matrix. The second stable R form and the fourth stable H form were produced by UV irradiation ( λ > 290 nm). The third stable O form was assumed to return immediately to E form even if it was produced. Ketoketene–water complex was yielded from R form by dissociation of the H and OH parts interacting through intramolecular hydrogen bonding upon prolonged UV irradiation.

Infrared (IR) spectra of the enol and keto forms of 4-amino-6-oxopyrimidine (AOP) isolated in a low-temperature Xe matrix were recorded, where the change from the keto to the enol form was found to be induced by UV irradiation ( λ > 270 nm). On the other hand, the hydrated crystal of AOP exhibited a similar IR spectrum to the anhydrous crystal by dehydration, suggesting that the dehydrated and anhydrous crystals are polymorphs. It has been found from the IR spectral analyses that the AOP crystal is dominated by infinite double H-bonded ribbons, which has been supported by quantum chemical calculations.

Conformations and photoreaction pathways of 3-chlorosalicylic acid have been investigated by low-temperature matrix-isolation infrared spectroscopy with an aid of the density-functional-theory calculation. It was found that only one conformer having an intramolecular hydrogen bond of Ph OH⋯O C in COOH existed in argon matrices after deposition before UV irradiation. Two less stable conformers were produced upon UV irradiation ( λ > 330 nm); one has an intramolecular hydrogen bond of Ph OH⋯OH in COOH, and the other has two intramolecular hydrogen bonds of COOH⋯OH Ph and Ph OH⋯Cl. Another conformational change between the less stable conformers was observed when the matrix was exposed to the shorter-wavelength UV light ( λ > 290 nm) for 1 min following the 300-min longer-wavelength UV irradiation ( λ > 330 nm). The photoreaction pathways due to the conformational changes were supported by a kinetic analysis using the IR absorbance changes of the photoproducts against the irradiation time.

Chemiluminescence emission spectra of polypropylene pellets pre-irradiated in air with γ rays were measured using a time-dependent multichannel Fourier-transform chemiluminescence spectrometer. Spectra were detected immediately after heating the irradiated polymer at 150 °C, which was not the case for the virgin material, and deconvoluted into emission bands by least-squares fitting using Gaussian curves. The peak intensity of the initial emission band around 490 nm rapidly increased and then decreased with a constant peak wavelength during the thermal oxidation time between 0 and 10 min. We have elucidated the emission mechanism from the dependence of γ -irradiation dose on the peak intensity.

Thermal oxidative degradation of additive-free polypropylene pellets heated isothermally in dry air at 150 and 180 °C (below and above the melting point of 163 °C) was investigated by multichannel Fourier-transform chemiluminescence spectroscopy. The initial peak wavelength of chemiluminescence emission at 490 nm remained constant during the early stages of thermal degradation, but new emissions developed with time in the red spectral region over an extended oxidation period. The time-dependent luminescence spectra were deconvoluted into three emission bands by least-squares fitting using Gaussian curves. We concluded that at least three groups of luminescent species (luminophores), having different conjugation lengths, were generated by thermal oxidation over extended periods and show luminescence around 490, 660, and 740 nm.

Delayed fluorescence spectra of intact leaves of Green pak choi (Brassica rapa var. chinensis) were measured with a multichannel Fourier-transform chemiluminescence spectrometer, which we developed recently. The intact samples, photoexcited by sunlight without artificial light sources, showed delayed fluorescence around 740 nm with a lifetime of ∼6 s. The observed spectra were deconvoluted into two Gaussian bands: the delayed fluorescence from photosystem II and photosystem I complexes. Their relative intensities depended on the chlorophyll concentration, but their wavelengths were unchanged.

The UV-induced photoreaction of 9-methyladenine was investigated by low-temperature matrix-isolation infrared (IR) spectroscopy with an aid of the density-functional-theory (DFT) calculation. Shorter-wavelength irradiation, λ > 240 nm, caused the elimination of a hydrogen atom in the amino group, resulting in the production of two kinds of amino radicals: One immediately changed to an imine isomer by migration of the eliminated hydrogen atom to a nitrogen atom in the pyrimidine ring, while the other stayed unreacted in the matrix for a long time. The imine returned to the original reactant, 9-methyladenine, by longer-wavelength irradiation, λ > 270 nm. The conformations of the unreacted radical and the imine were determined by comparison of the observed IR spectra with the spectral patterns obtained by DFT calculations.

UV-induced photoreactions of 4-chlororesorcinol (4-chloro-1,3-benzenediol; denoted as Cl-RN) and 4,6-dichlororesorcinol (4,6-dichloro-1,3-benzenediol; denoted as Cl-RN-Cl) in low-temperature argon matrices have been investigated by infrared (IR) spectroscopy and density-functional-theory (DFT) calculation. In the photolysis of Cl-RN, elimination of HCl occurred to produce a ketocarbene, which immediately changed to a five-membered ring ketene (3-hydroxy-2,4-cyclopentadiene-1-ylidenemethanone; denoted as HO-CPYM) by Wolff rearrangement. In addition, dissociation of CO from the C C O part of HO-CPYM occurred to produce 2,4-cyclopentadienone (CPDN) by intramolecular hydrogen-atom migration from the OH group to the carbene atom. Similarly, in the photolysis of Cl-RN-Cl, HO-CPYM-Cl was produced by elimination of HCl and Wolff rearrangement, which changed to Cl-CPDN by intramolecular hydrogen-atom migration. The conformations around the C O bonds of the reactants, Cl-RN and Cl-RN-Cl, and the intermediates, HO-CPYM and HO-CPYM-Cl, are determined by comparison of the observed IR spectra with the corresponding calculated spectral patterns obtained by the DFT method.

A UV-light induced photoreaction product of adenine in low-temperature argon matrices was identified as an adenine radical, where the hydrogen atom in the N H group was detached from adenine, by analyses of IR and UV–visible absorption spectra with aids of the density-functional-theory (DFT) and time-dependent DFT calculations. The adenine radical returned to adenine by recombination with the detached hydrogen atom upon longer-wavelength UV irradiation. A reversible isomerization to another adenine isomer via the adenine radical was also observed when the wavelength of UV irradiation was changed. The photoreaction mechanism of adenine in low-temperature argon matrices is discussed, including UV-light induced amine–imine tautomerism.

Infrared spectra of 4-bromo-2-chloro-6-fluorophenol in low-temperature argon matrices were measured with an FTIR spectrometer. Despite that an F-type geometrical isomer, which has an intramolecular hydrogen bond of OH⋯F, is as stable in the CCl 4 solution at room temperature as a Cl-type geometrical isomer, which has that of OH⋯Cl, no infrared bands of the F-type were observed in an argon matrix at 20 K. This implied that the F-type changed to the more stable Cl-type by hydrogen-atom tunneling in the argon matrix. To confirm the tunneling isomerization, similar experiments on the deuterated species were performed, resulting in that an O D stretching band of the F-type appeared as well as that of the Cl-type. This finding suggested that a deuterium is inhibited from the tunneling migration. The UV-induced photoreaction pathways of 4-bromo-2-chloro-6-fluorophenol were additionally examined, resulting in that 2-fluoro-4-bromocyclopentadienylidenemethanone was produced from the Cl-type by Wolff rearrangement after dissociation of the H atom in the OH group and the Cl atom. However no cyclohexadienone derivative, which is analogous to a photoproduct of a parent molecule, 2-chloro-6-fluorophenol, was produced upon UV irradiation. It is concluded that the bromine atom located at the 4th position disturbs the intramolecular migration of the Cl atom.

The photoreaction mechanisms of 2-naphthol and carbazole in low-temperature argon matrices have been investigated by infrared and electronic absorption spectroscopy with aids of density-functional-theory (DFT) and time-dependent DFT (TD-DFT) calculations. When the matrix samples were irradiated upon UV light, 2-naphthoxyl and N-carbazolyl radicals were produced by the elimination of the H atom in the O-H group of 2-naphthol and in the N-H group of carbazole, respectively. The observed IR and electronic absorption spectra of the radicals were reproduced satisfactorily by the quantum chemical calculations. To understand a role of the radicals in the excited-state proton transfer (ESPT), the fluorescence and excitation spectra of 2-naphthol and carbazole were measured in aqueous solution at room temperature as well as in the low-temperature argon matrices. It was found that the intensity of the fluorescence emitted from carbazole anion in aqueous solution decreased when oxygen gas was blown into the solution.

Chemiluminescence spectra of natural rubber, chloroprene rubber and ethylene propylene diene rubber were measured in N2 and in air with a multichannel Fourier-transform chemiluminescence spectrometer. Samples were measured after γ-ray irradiation in air and in the absence of O2. No strong emission was observed for natural rubber heated in N2 after the sample was γ-irradiated in the absence of O2, but a strong emission from the sample was observed at 631 nm in air. An emission from chloroprene rubber was observed around 659 nm even when the sample was not γ-irradiated. A similar band was observed after the sample was γ-irradiated in air and in the absence of O2. A strong emission from ethylene propylene diene rubber was observed in air only when the sample was γ-irradiated in air. The observed spectrum was separated into two bands at 678 and 523 nm, where the former and the latter were tentatively assigned to peroxidic compounds and excited carbonyl groups, respectively. The relative intensity of the two bands changed during the measurement. It is concluded that luminescence spectroscopy using a multichannel spectrometer is a powerful technique to examine the oxidative degradation of elastomers. Chemiluminescence spectra of natural rubber, chloroprene rubber and ethylene propylene diene rubber were measured in N2 and in air with a multichannel Fourier-transform chemiluminescence spectrometer. Samples were measured before and after γ-ray irradiation in air and in the absence of O2. A strong emission from ethylene propylene diene rubber was observed in air only when the sample was γ-irradiated in air. The observed spectrum was separated into two bands at 678 and 523 nm because of peroxidic compounds and excited carbonyl groups, respectively.

The thermal chemiluminescence spectra of the dicyclohexylamine (DCHA) salts of glycine, alanine, serine, and threonine were measured with a multichannel Fourier-transform chemiluminescence (FT-CL) spectrometer. The zwitterionic amino acids themselves are non-luminescent because their amine groups are protonated, whereas the corresponding DCHA salts show strong emission in the presence of oxygen because their NH 2 groups are free. It was found that the CH 3 and OH groups on the side chain caused red and blue shifts, respectively, suggesting that thermal luminescence spectroscopy using an FT-CL spectrometer can be used to identify the presence of electron donating or withdrawing groups in chemiluminescent molecules.

Thermal luminescence (TL) spectra of polyamides were measured with a Fourier-transform chemiluminescence spectrometer to elucidate the emission mechanism. A TL band of e-polylysine with a peak at 542 nm observed at 403 K was assigned to the emission due to the interaction of the –CO–NH– group with oxygen molecules by comparison with nylon-6, polyglycine, and polyalanine. When the sample was kept at 453 K, the intensity of the TL band decreased and the wavelength of the peak shifted to 602 nm, which was assigned to the emission due to the interaction of the NH2 group on the side chain with oxygen molecules by comparison with monomeric lysine. A weak emission with a peak at 668 nm was assigned to the advanced glycosylation end products (AGEs) yielded by the Maillard reaction with a catalytic amount of water. To understand this reaction and to examine the TL emission of AGEs, we measured TL spectra of mixtures of polylysine and reducing sugars such as glucose, maltose, lactose, and dextrin. The minimum temperature for TL emission, wavelength of the peak and the relative intensities of the TL emission were found to depend on the size of the sugars. Copyright © 2011 John Wiley & Sons, Ltd.

Infrared spectra of 2-chloro-6-fluorophenol in argon matrixes at 20 K revealed the presence of a "Cl-type" isomer, which has the OH···Cl hydrogen bond, but no "F-type" isomer with OH···F bonding, in striking contrast to the existence of both isomers in the gas and liquid phases at room temperature. This finding suggests that the F-type isomer changes to the more stable Cl-type one by hydrogen-atom tunneling in the matrixes. Similar experiments on the OD···X analog species were performed to confirm the tunneling isomerization, resulting in an O-D stretching band of the F-type isomer appearing as well as that of the Cl type, like the spectra reported in the gas and liquid phases. This implies that tunneling migration of the D atom is inhibited in the argon matrix. In addition, UV-induced photoreactions of 2-chloro-6-fluorophenol were studied by a joint use of matrix-isolation IR spectroscopy assisted by density functional theory calculations. It was found that 2-fluorocyclopentadienylidenemethanone and 4-chloro-2-fluorocyclohexadienone were produced from the Cl type; the former was by the Wolff rearrangement after dissociation of the H atom in the OH group and the Cl atom, and the latter was by intramolecular migration of the H and Cl atoms. As for the deuterated F-type isomer, however, 2-chlorocyclopentadienylidenemethanone was produced by the Wolff rearrangement after dissociation of the D atom in the OD group and the F atom, besides other photoproducts of the deuterated Cl-type isomer. It is thus concluded that the tunneling isomerization around the C-O bond occurs in the OH···X species but not in the OD···X species.

Infrared spectra of ethanol in low-temperature argon and xenon matrices were measured with an FT-IR spectrometer. The relative intensities of the IR bands for anti and gauche conformers changed according to the Boltzmann distribution law, when the matrix temperature was varied in the ranges between 15 and 30 K in argon and between 15 and 55 K in xenon. The energy difference between the two conformers was determined from the spectral changes to be 29.4 ± 2.1 cm −1 in argon and 20.0 ± 1.2 cm −1 in xenon, where anti is more stable than gauche. The results are discussed in terms of the interaction between an ethanol molecule and noble-gas atoms.

A thermal luminescence spectrum of solid lysine in O 2 with an emission peak at ∼600 nm was measured at 450 K with a Fourier-transform chemiluminescence spectrometer. No emission bands were observed for lysine in N 2 , nor its monohydrochloride in O 2 or N 2 , under the same experimental conditions. This observation led us to the conclusion that the intermolecular interaction between the free NH 2 group on the side chain of lysine and O 2 molecules plays an essential role in this thermal luminescence. This scheme was given support by the finding that the dicyclohexylamine salt of phenylalanine, which has a free NH 2 group, but not phenylalanine itself, showed similar thermal luminescence in O 2 .

Photoreaction of 7-hydroxyquinoline monomer in a low-temperature argon matrix was investigated, and electronic absorption spectra of three unstable species generated by UV-light irradiation were measured. By comparison with the calculated spectral patterns obtained by the time-dependent density-functional-theory calculation, the electronic absorption bands around 460, 360 and 260 nm appearing after UV irradiation were assigned, respectively, to the keto form produced from the enol form of 7-hydroxyquinoline by migration of the hydrogen atom of the OH group to the N atom, quinolinoxyl radical by elimination of a hydrogen atom, and 7-ketene by Wolff rearrangement following elimination of a hydrogen molecule.

Photoreactions of 7-hydroxyquinoline (7-HQ) in low-temperature (77-100 K) 2-methyltetrahydrofuran glass matrices are investigated using electronic spectroscopy. We have observed fluorescence excitation and fluorescence spectra of two long-lived species generated by irradiation of UV light (230-400 nm). The dominant species responsible for the fluorescence spectrum between 470 and 600 nm was assigned to the S(1)-->S(0) (pipi*) transition of the keto form of cyclic 7-HQ dimer [(7-HQ)(2)] produced by excited-state double-proton transfer, the corresponding S(1)-S(0) fluorescence excitation spectrum of which was detected between 360 and 510 nm. Temperature dependence of the fluorescence excitation spectra showed the occurrence of keto --> enol isomerization in the S(0) state of (7-HQ)(2) due to a back double-proton transfer. A very slow rate for the keto --> enol isomerization implies that the potential barrier height for the back double-proton transfer reacion is substantially high. Theoretical calculations at the MP2/aug-cc-pVDZ level of theory indicate that the enol and keto forms of cyclic (7-HQ)(2) are nonplanar, therefore a large change in the geometry is necessary for the back double-proton transfer. A second long-lived species that emits between 410 and 600 nm has been tentatively assigned to the D(3)(2A'') --> D(0)(1A'') transition of the 7-quinolinoxyl radical on the basis of calculated electronic transition energies for possible candidates obtained by MS-CASPT2/aug-cc-pVDZ level calculations as well as IR study of 7-HQ in argon matrices [Sekine, M.; Nagai, Y.; Sekiya, H.; Nakata, M. J. Phys. Chem. A 2009, 113, 8286]. Photoreaction processes leading to the two long-lived species have been discussed.

Photoreaction mechanisms of 6-hydroxyquinoline (6-HQ) and 7-hydroxyquinoline (7-HQ) in low-temperature argon matrixes have been investigated by Fourier transform infrared (IR) spectroscopy and density-functional-theory (DFT) calculations. A comparison of the observed IR spectra of reactants with the corresponding calculated spectral patterns obtained by the DFT method led to the conclusion that the hydrogen atoms in the O-H group of 6-HQ and in that of 7-HQ are selectively located at the outer position against the quinoline ring. When the matrix samples were irradiated upon UV light around 300 nm, IR spectra of unknown chemical species were observed; they were assigned to the photoreaction intermediates, quinolinoxyl radicals and ketene compounds, produced by eliminations of a hydrogen atom and a hydrogen molecule, respectively. In the photoreaction of 7-HQ, a small amount of keto form was also produced by intramolecular hydrogen-atom transfer from oxygen to nitrogen in an argon cage. Kinetic analyses were made by assuming that 5-ketene and 6-ketene were produced from 6-HQ, while 6-ketene and 7-ketene were produced from 7-HQ. The effective rate constants estimated from the absorbance changes of IR bands against irradiation time revealed that the reaction pathway to produce 6-ketene was minor in both HQs, leading to the conclusion that the conformation of reactants, HQs, plays an important role in the photoproduction of ketenes through biradicals in the Wolff rearrangement.

Fourier-transform chemiluminescence spectra of H 2 O 2 /gallic acid/K 3 [Fe(CN) 6 ] systems containing organic solvents were measured. Emission bands with peaks around 530 and 700 nm were observed in systems containing solvents with a carbonyl group such as N , N -dimethylformamide, and those with a hydroxyl group such as methanol, respectively. The relative band intensities depended strongly on the concentration of these organic solvents. The emission species are attributed to gallic acid–ferricyanide complexes excited by energy transfer from singlet oxygen dimol, ( 1 O 2 ) 2 . The effects of organic solvents are interpreted in terms of intermolecular interactions of gallic acid–ferricyanide complexes, water molecules and organic solvents.

The JEOL Automated Data Acquisition System (JADAS) is a software system built for the latest generation of the JEOL Transmission Electron Microscopes. It is designed to partially or fully automate image acquisition for ice-embedded single particles under low dose conditions. Its built-in flexibility permits users to customize the order of various imaging operations. In this paper, we describe how JADAS is used to accurately locate and image suitable specimen areas on a grid of ice-embedded particles. We also demonstrate the utility of JADAS by imaging the epsilon 15 bacteriophage with the JEM3200FSC electron cryo-microscope, showing that sufficient images can be collected in a single 8 h session to yield a subnanometer resolution structure which agrees with the previously determined structure.

The gasification behavior of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in fly ash by thermal treatment has been investigated to estimate gas-particle partition in flue gas. The results obtained in thermal experiments under various conditions showed that gasification of PCDD/Fs depends on air flow rate and treatment weight of fly ash as well as treatment temperature. On the other hand, the results obtained in the thermal experiments using dioxin-free fly ash revealed that during thermal treatment, the de novo synthesis, gasification, and decomposition of PCDFs proceeded at different rates. This difference in the reaction rates indicates that thermal treatment time is also a factor in determining the gas-particle partition of PCDD/Fs in fly ash. Therefore, reasonable thermal treatment conditions were established and applied to three ash samples. For all samples, PCDD/Fs started to gasify at 350 degrees C treatment, whereas 53-98% of PCDD/F homologs gasified at 400 degrees C treatment, implying that gaseous PCDD/Fs are dominant in flue gas at temperatures in the range 350-400 degrees C regardless of particle concentration.

A Fourier-transform spectrometer equipped with a Savart-plate polarization interferometer was developed for observation of weak chemiluminescence and applied to a measurement of emission spectra in the decomposition of hydrogen peroxide with gallic acid and K3[Fe(CN)6]. The band appearing at ∼580 nm in the chemiluminescence spectrum was assigned to the emission of singlet-oxygen dimol, the peak wavelength being shifted from that observed in the reaction of hydrogen peroxide with sodium hypochlorite, ∼633 nm. The band intensity was increased with the increasing concentration of K3[Fe(CN)6] up to ∼100 mM, and thereafter the peak wavelength was shifted from 580 to 700 nm with a decrease in the intensity.

The photoreaction mechanism of 2-chloropropionic acid in a low-temperature argon matrix has been investigated by Fourier transform infrared spectroscopy with an aid of density-functional-theory calculations. The photoisomerization from syn to anti around the C O bond with the isomerization around the central C C bond was observed when the matrix sample was exposed to UV light ( λ > 240 nm). In the anti isomer produced in this reaction, the hydrogen atom in the carboxyl group is so close to the chlorine atom that this isomer changed to a less stable photoreaction intermediate by elimination of HCl. The photoreaction intermediate, which showed a strong C O stretching band around 1910 cm −1 , was assigned by comparison with the calculated spectral pattern to methyloxiranone, a 3-membered lactone. This photoreaction mechanism was confirmed by a kinetic analysis for the absorbance changes of the reactant and intermediate bands.

Intramolecular hydrogen atom tunneling in 2-chlorobenzoic acid has been investigated by low-temperature matrix-isolation infrared spectroscopy with the aid of density functional theory calculation. Infrared spectra of two relatively stable syn isomers, SC and ST, were observed in argon and xenon matrixes. When the matrix samples were annealed after deposition, the isomerization from ST to SC occurred around the benzene-carboxyl bond. Two less stable anti isomers, AT, which has an OH...Cl intramolecular hydrogen bond, and AC, which has no OH...Cl bond, were produced from SC and ST upon UV irradiation. When the matrix samples were kept in the dark after UV irradiation, AT and AC changed to ST and SC, respectively, by spontaneous isomerization around the C-O axis in the carboxyl group. The rate constants of isomerization, AT --ST, in a Xe matrix were estimated from the absorbance changes at various matrix temperatures. The rate constants showed a drastic decrease in deuteration of the hydrogen atom of the carboxyl group. The relationship between the rate constants and the matrix temperature did not follow the Arrhenius law. These findings lead to the conclusion that the isomerization of AT --ST and AC --SC in low-temperature rare-gas matrixes proceeds through intramolecular hydrogen atom tunneling.

Intramolecular hydrogen-atom migrations in 2-hydroxy-3-nitropyridine have been investigated by low-temperature matrix-isolation infrared (IR) spectroscopy with the aid of density functional theory (DFT) calculation. An IR spectrum measured after deposition was assigned to an enol isomer, the conformation of which is anti in relation to OH versus N in the pyridine ring. When the matrix sample was exposed to UV and visible light (lambda>350 nm), an IR spectrum consistent with a keto product was observed. During the irradiation, an IR spectrum of a transient species, a photoreaction intermediate between anti-enol and keto, was observed, which was assigned to syn-enol. The bands of syn-enol disappeared completely when the irradiation was stopped, while those of the original isomer, anti-enol, reappeared. No reverse isomerization was observable in the corresponding deuterated species. This led to the conclusion that the isomerization from syn to anti occurs through hydrogen-atom tunneling. On the other hand, an aci-nitro form was produced by UV irradiation (lambda=365+/-10 nm) without visible light. The conformation around the aci-nitro group was determined to be cis-cis by comparison with the spectral patterns obtained by the DFT/B3LYP/6-31++G** calculation. The dynamics of the hydrogen-atom migrations between anti- and syn-enols, syn-enol and keto, and anti-enol and aci-nitro are discussed in terms of the potential surfaces obtained by the DFT calculation.