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Floret senescence of Oxypetalum caeruleum was investigated in relation to ethylene production and its sensitivity to ethylene. Ethylene production increased as the florets senesced, and conversely, their senescence was accelerated by exogenous application of ethylene at 2 or 10 μl·liter-1 for 24 hr, indicating that Oxypetalum florets are sensitive to the gaseous hormone. Treatment with silver thiosulphate complex (STS), an ethylene action inhibitor, extended the vase life of florets. Thus, ethylene is considered to be involved in the senescence of cut Oxypetalum florets.

Fragmentation of doubly charged ethanol clusters [(C(2)H(5)OH)(n)] following the O 1s ionization has been investigated by means of the photoelectron-photoion-photoion coincidence (PEPIPICO) method. The dominant fission channel of (C(2)H(5)OH)(n)(2+) was the formation of protonated cluster ion pairs [H(C(2)H(5)OH)(l)(+)/H(C(2)H(5)OH)(m)(+)]. The fragmentation mechanisms of these ion pairs were discussed based on the analysis of the PEPIPICO contour shape. It was clarified that the prominent fragmentation channel was a secondary decay mechanism, where neutral evaporation occurs after charge separation. On the other hand, the formation of small fragment ions was suppressed, excluding the formation of certain specific fragments (H(3)O(+), C(2)H(5)(+)/COH(+), and C(2)H(4)OH(+)). The formation of small fragment ions was suppressed due to the cooling effect caused by the neutral evaporation and the decrease in the electrostatic repulsive force caused by charge separation.

We have designed and constructed the apparatus for the angular distribution measurements of photoejected electrons and ions from free molecules, as a part of the endstation of the c -branch of the beamline BL27SU, a soft X-ray photochemistry beamline at SPring-8. The experimental procedures are described in combination with the use of a capability to switch the horizontal and vertical directions of the linear polarization of the light produced by the figure-8 undulator. As a typical example of the experimental results, we present angle-resolved energetic ion yield spectra in the O 1s excitation region of CO 2 .

Total electron–ion–ion coincidence measurements on core excited organic molecules have been carried out with high mass resolution by using multimode (reflectron/linear) time-of-flight mass analyzer. From the ion correlation spectra of core excited CH3OH and CD3OH, the reaction pathway to form H3+ (D3+) is identified as the elimination of three H (D) atoms from the methyl group, not as the inter-group (–CH3 and –OH) interactions. In a PEPIPICO spectrum of acetylacetone (CH3COCH2COCH3) measured by using a reflectron TOF, correlations between ions up to mass number 70 with one-mass resolution was recorded.

Photoabsorption and fluorescence excitation spectra of CHBr2Cl and CHBrCl2 trihalomethanes were measured in the 106–200 nm region using synchrotron radiation as a light source. Main photoabsorption bands observed are assigned as the Rydberg transitions of the outer shell orbitals. In the photoexcitation of CHBr2Cl a diffuse emission band of CHCl(A 1A‘→X 1A’) was observed in the 500–800 nm region. The radiative lifetime of the CHCl(A 1A‘) state was first determined to be 7.01±0.25 μs. In the photolysis of CHBrCl2 at 121.6 nm, the formation of CHCl(A 1A‘) and CCl2(A 1B1) radicals were observed. The fluorescence thresholds for CHBr2Cl and CHBrCl2 start at 162 and 159 nm with the maximum yields of 5% and 11% at 122 and 119 nm, respectively.

No abstract available. Image: Chest CT showing bilateral diffuse ground-glass opacities in both lungs., JOP. Journal of the Pancreas, Vol 11, No 2 (2010): March - p. 95-198

Photoabsorption and fluorescence excitation spectra of CHBr2Cl and CHBrCl2 trihalomethanes were measured in the 106–200 nm region using synchrotron radiation as a light source. Main photoabsorption bands observed are assigned as the Rydberg transitions of the outer shell orbitals. In the photoexcitation of CHBr2Cl a diffuse emission band of CHCl(A 1A‘→X 1A’) was observed in the 500–800 nm region. The radiative lifetime of the CHCl(A 1A‘) state was first determined to be 7.01±0.25 μs. In the photolysis of CHBrCl2 at 121.6 nm, the formation of CHCl(A 1A‘) and CCl2(A 1B1) radicals were observed. The fluorescence thresholds for CHBr2Cl and CHBrCl2 start at 162 and 159 nm with the maximum yields of 5% and 11% at 122 and 119 nm, respectively.

A focusing soft x‐ray beam line equipped with a focusing premirror and a double crystal monochromator (DXM) has been constructed at BL1A in the UVSOR. An elliptically bent cylindrical mirror was used as the focusing premirror in order to attain both horizontal and vertical focusing at the sample position. Ray tracing shows that the size and shape of the focused spot at sample position with an elliptically bent cylindrical mirror is almost the same as that of an ellipsoidal mirror. Measured spot size of the monochromatic x‐ray beam at the sample position was about 2 mm wide and 1 mm high, which is in good agreement with the result of ray tracing. Monochromatic x rays were observed up to 4 keV even after reflection by a platinum coated premirror with grazing angle of 1°.

The visible edge radiation generated by a relativistic electron beam at fringe fields of bending magnets in storage rings differs significantly from the well-known standard synchrotron radiation. An intensive peak appears in the electromagnetic radiation angular distribution. Its intensity exceeds considerably the intensity of synchrotron radiation. In addition, the radiation generated at two adjacent edges of bending magnets produces an interference pattern. The real electron beam parameters (its transversal sizes and angular spread) have effect on the radiation intensity distribution. It is possible to find the electron beam parameters from the experimentally measured edge radiation distribution. Such electron beam diagnostics as applied to HiSOR storage ring (Hiroshima, Japan) is discussed in the present paper.

A study of the excitation energy dependence of resonant X-ray emission spectra across the O1s absorption edge in combination with X-ray absorption spectroscopy and density functional theory reveals the site-specific valence electronic structure of liquid acetic acid under ambient conditions.

The location and identity of low-lying electronic states of jet-cooled isoquinoline have been investigated by multiphoton ionization photoelectron spectroscopy, involving one-color well as two-color ionization schemes. The results provide evidence for the presence of an nπ* triplet state lying between the lowest excited singlet state of nπ* character and the lowest triplet state of /gp/gp* character.

The direct absorption spectrum of benzene in a free jet has been measured in the 130–260 nm region (S1, S2, and S3 states, Rydberg series, and the first ionization limit) using synchrotron radiation as a light source. The absolute molar extinction coefficients (e) of benzene in jets have been determined by scaling measured free‐jet values to the known value in the vapor phase for a broadband at 200.1 nm in the S2 state. The vibrational temperature for ν16 mode was estimated to be 185 K. The maximum value of e of the S1 absorption system was found to be 1400 l mol−1 cm−1 (spectral bandwidth=0.065 nm). A shoulder observed at 205.45 nm in the S2 absorption system is assigned to the S2 origin, induced by pseudo‐Jahn–Teller distortion.

The absorption spectrum of solid Ne measured in the 800-1300 eV region is presented. Two sharp peaks near the K -edge around 865 eV which correspond to the 1 s →3 p and 1 s →4 p transitions in gaseous Ne are attributed to the excitonic transitions. Above the ionization energy of 1 s electron in gaseous Ne, many structures are observed in solid Ne.

The direct absorption spectra of benzene in jets are measured in the wavelength region of the S 2 and S 3 system, using synchrotron radiation (SR) as a light source. Two broad absorption maxima are found at 208 and 185 nm and assigned, respectively, to the S 2 and the S 3 absorption system of benzene clusters. Large stability in the S 2 and S 3 states upon cluster formation, by at least 6 kcal/mol, is concluded from the observed red-shifts with respect to the monomer bands.

Journal URL: http://www.sciencedirect.com/science/journal/03682048

We study the electronic structure and chemical bonding of the ${\text{SO}}_{2}$ molecule adsorbed on Ni(100) surface using x-ray emission spectroscopy at the $\text{O}\text{ }1s$ absorption edge. Elemental and symmetry specificities of the method enable us to directly probe surface chemical bonding formed by strong hybridization of $\text{O}\text{ }2p$ with $\text{Ni}\text{ }3d$ orbital. Contrary to the expected $\ensuremath{\pi}$ bonding due to strong $\ensuremath{\pi}$ acceptor character of the ${\text{SO}}_{2}$ molecule, we find electronic structures with both $\ensuremath{\sigma}$ and $\ensuremath{\pi}$ characters just below the Ni Fermi level. The details of this complicated surface chemical bonding are discussed using a calculation based on density-functional theory.

Hydrogen bonding in methanol clusters has been investigated by using inner-shell photoabsorption spectroscopy and density functional theory (DFT) calculations in the carbon and oxygen K-edge regions. The partial-ion-yield (PIY) curves of H(CH(3)OH)(n)(+) were measured as the soft x-ray absorption spectra of methanol clusters. The first resonance peak in the PIY curves, which is assigned to the sigma*(O-H) resonance transition, exhibits a 1.20 eV blueshift relative to the total-ion-yield (TIY) curves of molecular methanol in the oxygen K-edge region, while it exhibits a shift of only 0.25 eV in the carbon K-edge region. Decreased intensities of the transitions to higher Rydberg orbitals were observed in the PIY curves of the clusters. The drastic change in the sigma*(O-H) resonance transition is interpreted by the change in the character of the sigma*(O-H) molecular orbital at the H-donating OH site due to the hydrogen-bonding interaction.

Photoabsorption and fluorescence excitation spectra of CHFCl2 and CHFBr2 were measured in the wavelength region 106–200 nm using synchrotron radiation as a light source. The Rydberg excitations of the outer shell orbitals are discussed. The He(i) photoelectron spectrum of CHFBr2 was first measured. Diffuse emission band of CHF(A 1A‘→X 1A’) was observed in the 350–700 nm region, in which the 2n0 (n=0–4) vibrational progression and 201 transition were identified. The CClF(A 1A‘) radical was produced together with CHF(A 1A‘) in the photodecomposition of CHFCl2. The radiative lifetimes of the A 1A‘ states of CHF and CClF were determined to be 2.57±0.16 μs and 644±15 ns, respectively. In the photolysis of CHFCl2 fluorescence starts at 155 nm and shows a maximum quantum yield Φ=0.22 at 107.5 nm, while the CHFBr2 excitation gives a maximum of Φ=0.016 at 117.5 nm.

The photoabsorption cross sections and fluorescence excitation spectra of group IIb dimethylmetals were measured using synchrotron radiation at 106–270 nm. The observed absorption bands were accounted for in terms of Rydberg transitions. The fluorescence spectra of MCH3 (A 2E→X 2A1) transitions were observed and the radiative lifetimes determined were 47±2 and 62±2 ns for M=Zn and Cd, respectively. The excited M(np 3P01) atoms were detected in the photolyses of dimethylcadmium and dimethylmercury, but not in dimethylzinc. The formations of the electronically excited MCH3 (A 2E) and M(np 3P01) states are characteristic of the Rydberg excitations of the C–H in methyl and M–C bonding electrons, respectively.

Photodissociative excitation processes of gaseous HNCO are studied in the wavelength region 107–180 nm using synchrotron radiation as a light source. Fluorescence excitation spectra of the photofragments, NH(c 1 Π, A 3 Π) and NCO(A 2 Σ), are measured under near collision-free conditions. The quantum yields for formation of these excited radicals are also determined.

Due to the rapid increase of the population of elderly people, many countries have serious social problems. Technical approach is highly required to deal with such problems. One of serious problem can be found at nursing care of patients suffered by intractable disease like ALS (Amyotrophic Lateral Sclerosis) and cerebral infraction. They need intensive cares by care-workers. As a typical symptom of ALS patients their muscular functions deteriorate rapidly. In two or three years after the onset of the disease, patients are often obliged to use artificial respirators since even the breathing action becomes impossible. Once they start to use the artificial respirator, uttering voice becomes impossible. Therefore, communication with family and friends becomes difficult In this presentation activity to support daily lives of these serious patients in Nagasaki area are explained. We developed and offered communication system using original switching devices. These switches are developed considering individual symptom of the patients. Using the Internet function of the system, the patients are able to join the social activity.

Soft X-ray absorption spectra of the lowest excited triplet states of several organic molecules (quinones, benzaldehydes, and other carbonyls) and potential curves of valence- and core- doubly excited states are calculated for the O 1s region.

Synchrotron radiation emitted from the UVSOR storage ring is monochromated by a grazing-incidence monochromator and introduced coaxially with the second harmonic of a mode-locked Ti:sapphire laser. Sample gases, N2 and N2O, are photoionized into vibronically ground N2 + with the fundamental light of the undulator radiation at 18.0 and 18.6 eV, respectively. Laser-induced fluorescence (LIF) excitation spectra of N2 + from N2 and N2O are measured in the laser wavelength region of the (B 2Σ u +, v′ = 0) ← (X 2Σg +, v′′ = 0) transition at 389–392 nm. The LIF excitation spectra of N2 + exhibit two maxima due to the P and R branches in which rotational bands are heavily overlapped. The rotational temperature is determined by simulating an LIF excitation spectrum by using the theoretical intensity distribution of rotation bands convoluted with the spectral width of the laser.

Time-of-flight mass spectra have been measured for inner-shell ionization of ethanol molecules, its clusters, and methanol clusters at the oxygen K-edge regions. Only in the case of the ethanol clusters, a fairly intense signal corresponding to H 3 O + has been observed. The measurements for ethanol- d 1 (C 2 H 5 OD) suggest that at least one H atom in the H 3 O + ion originates from the C 2 H 5 group of neighbouring ethanol. It is proposed that in addition to the O–H⋯OH type hydrogen bonding in the ethanol clusters, the H in the C 2 H 5 group and OH interact with each other.

Ionic fragmentation of core-excited α-alanine in gas phase was observed. The most dominant ionic species is COOH+ for all core-ionizations at C 1s, N 1s, and O 1s. An increase in COO+ and a decrease in COOH+, which were observed as core-hole atom selectivity for the O 1s ionization, are explained by the enhancement of O–H bond scission. Further state-selective O–H bond scission, observed at the O 1s second peak, is attributed to the OOH1s → 3s/σ* transition.

Dissociation of free methyl-formate (MF), HC(O)OCH3, and its clusters (MF)n, (HC(O)OCH3)n, induced by core-level excitation was studied near the oxygen K edge by time-of-flight fragment-mass spectroscopy. Besides the protonated clusters, (MF)nH+ with n < or = 15, we identified the production for another series of (MF)mCH3OH2+ with m < or = 14 as well as methyl-oxonium ion, CH3OH2+, characteristic of hydrogen transfer reactions in the cationic clusters. Here; specifically labeled methyl-formate-d (MFD), DC(O)OCH3 was also used to examine the core-excited dissociation mechanisms. Deuterium-labeled experiments indicated that MFD+ with low internal energies, partially generated after the core excitation, produces CH3OD+ via a site-specific deuterium transfer from the alpha carbonyl in the molecular cation and that CH3OD2+ can be formed via the successive transfer of another deuterium from the neighbor molecule in the clusters. The deuteron (proton) transfer was also found to take place preferentially from the alpha carbonyl of the neighbor molecule for the production of deuteronated (MFD)nD+, (protonated (MF)nH+), clusters. The minimal energy requirement paths were examined for dimer (MF)2+ cation to support the present dissociation mechanisms of core-excited (MF)n clusters using ab initio molecular-orbital calculations.

We have studied amino acid formation by UV (193 nm) irradiation to organic molecules (amines, alcohols and amides) in aqueous solution. Among several types of detected amino acids, small aliphatic amino acids (Gly and alpha-, beta-Ala and alpha-, beta-, gamma-ABA) were quantitatively identified. Among these small aliphatic amino acids, certain amino acids were formed in its free form, even before hydrolysis, contrary to the results of UV irradiation to a gas mixture of CO, NH3, and H2O, where amino acids were hardly detected before hydrolysis. The species distribution of identified amino acids showed a dependence on the starting organic molecules, and also on the presence of ammonia. The formation processes of the identified small aliphatic amino acids were investigated with the aid of electrospray ionization (ESI) MS and MS/MS measurements of photoproducts. Possible formation processes of these amino acid precursors from each starting molecules are proposed. By identifying the amino acid precursor, which has a chiral carbon atom, a new possibility is suggested for asymmetric photosynthesis of amino acid from achiral organic molecules.

Vibrationally resolved spectra have been obtained for the lowest-lying cationic states X (2)B(1), A (2)A(1), and B (2)B(2) of the water molecule reached after participator resonant Auger decay of core-excited states. The angular distribution has been measured of the first four vibrational components of the X state in the photon energy regions including the O 1s-->4a(1) and the O 1s-->2b(2) core excitations, and for different portions of the vibrational envelope of the B state in the photon energy region including the O 1s-->2b(2) core excitation. For the X state, a large relative spread in beta values of the different vibrational components is observed across both resonances. For the B state, a very different trend is observed for the high binding energy side and the low binding energy side of the related spectral feature as a function of photon energy. A theoretical method based on the scattering K matrix has been used to calculate both the photoabsorption spectrum and the beta values, by taking both interference between direct and resonant photoemission and vibrational/lifetime interference into account. The numerical results show qualitative agreement with the trends detected in the experimental values and explain the conspicuous variations of the beta values primarily in terms of coupling between direct and resonant photoemission by interaction terms of different sign for different final vibrational states.

Vehicle manufacturers developed two mixture formation concepts for the first generation of gasoline direct-injection (GDI) engines. Both the wall-guided concept with reverse tumble air motion or swirl air motion and the air-guided concept with tumble air motion have the fuel injector located at the side of the combustion chamber between the two intake ports. This paper proposes a new GDI concept. It has the fuel injector located at almost the center of the combustion chamber and with the spark plug positioned nearby. An oval bowl is provided in the piston crown. The fuel spray is injected at high fuel pressures of up to 100 MPa. The spray creates strong air motion in the combustion chamber and reaches the piston bowl. The wall of the piston bowl changes the direction of the spray and air motion producing an upward flow. The spray and air flow rise and reach the spark plug. The fuel injection pressure, the spray shape and the piston bowl geometry are important factors for the performance of stratified combustion with this concept.

(Received 1 December 2003; published 27 February 2004)In the soft x-ray region, the demand for helicity switching of circularly polarized undulator radiationis increasing to study circular dichroism. The asymmetric figure-8 undulator is an insertion device toprovide circularly polarized radiation (CPR) and a simple method of helicity switching which has beenproposed and built at SPring-8. Because of its complicated magnetic structure, it is important tooptimize the magnetic parameters for more effective utilization of CPR. Using an analytical method,the relation between the magnetic parameters to maximize the degree of circular polarization isobtained. The impact of the finite emittance of electron beams on the polarization performance is alsoinvestigated numerically.

A novel undulator has been developed for the soft X‐ray beamline BL17SU of SPring‐8. Experiments to be done at the BL17SU require linearly/circularly polarized light and fast helicity switching of circular polarized light. In addition, it must have low power density on axis to avoid a heat load problem. Therefore, the undulator has three operation modes; it works as a helical undulator for circular polarized light, figure‐8 undulator for linear polarized light and asymmetric figure‐8 undulator for fast helicity switching. In order to realize three types of undulator, the novel undulator consists of electromagnets and permanent magnets. The magnetic field has been measured at each operation mode and performances have been calculated from the measurement results.

Twin helical undulators and five kicker magnets have been installed in the 5 m straight section of SPring‐8 BL25SU to provide helicity switched circularly polarized radiation in soft X‐rays. Helicity of circular polarization is changed by means of electron beam orbit bumps. We successfully increased frequency up to 10 Hz without disturbing the stability of the electron beam orbit.

A UHV apparatus for soft x‐ray spectroscopic studies on solids and surfaces has been constructed at the beamline BL27SU in SPring‐8. A newly developed flat field spectrometer with a CCD detector is equipped for soft X‐ray emission spectroscopy (SXES). The focused beam, less than 10μm in vertical direction, enables us to take entrance slit of the spectrometer away, and to achieve high detection efficiency without loss of incident beam. The energy resolution (E/ΔE) of around 1000 is realized in the energy range of 250–900 eV. An electron energy analyzer is also equipped for photoelectron spectroscopy (PES). An undulator called “Figure‐8” at this beamline supplies both horizontally and vertically polarized soft x‐rays so that we can get symmetry resolved SXES and PES spectra with ease by changing the polarization.