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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. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

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. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

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. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The total food waste constitutes a great portion of perishable goods and Kaya (2021) stated that inventory management has been proven to be more challenging for perishable goods since these deteriorate over time and become obsolete. This study will be significant for business owners in Convenience Store X in Marikina City and for future studies to have an effective inventory management. The objective of this study is to create user-focused inventory management system using a design thinking approach which is a five-stage process: Empathize, Define, Ideate, Prototype, Test. With that, the researchers gathered data and determined the users' pain points related to the inventory management system for perishable goods in Convenience Store X. Then, the researchers came up with criteria and solutions for the new inventory system with the use of Multi-Criteria Decision Analysis (MCDA), specifically Analytical Hierarchy Process (AHP) and integrated with software developers in designing the three (3) user interfaces of a Software-as-aservice (SaaS) inventory system namely: System X, System Y and System Z. Through the Pugh Selection and User Acceptance Test, the researchers collected ratings from the users and concluded that System X is the most preferred design based on the users' pain points and preferences. [ABSTRACT FROM AUTHOR]

Emissions coming out of an engine are the main cause of health hazards for humans and leaving beings, this has resulted in ever-tightening of the emission regulations. Currently, emissions coming out of the engine are reduced by using after-treatment devices like Oxidation Catalyst (DOC), Diesel Selective Catalytic Reduction (SCR), and Diesel Particulate Filter (DPF). However, after-treatment devices add significant cost. Sighting the same, a need is felt to achieve lower engine emissions with limited or no use of after-treatment devices. Use of alternate fuels, multi-fuel / fuel blends, and improvements in combustion technology are some of the major areas of focus. One of the methods of combustion improvement is Homogenous Charge Compression Ignition (HCCI) engine where the air-fuel mixture is ignited automatically without a spark or controlled fuel injection. This method is preferred over the after-treatment devices due to the lower cost of the solution and simultaneous reduction of NOx and HC. The current research work on HCCI concept and its applicability for diesel engines for genset application is reviewed in this paper. This review is mainly focused on HCCI combustion, genset engine requirements, transient control and alternate fuels for HCCI. Finally, this review concludes with the possible suggestion for future research in the field of diesel genset engines with HCCI concept. [ABSTRACT FROM AUTHOR]

The nature of the electronic structure and bonding in transition metal compounds is matter of intrinsic interest. High-energy spectroscopic are well suited to provide information on these points. Among them, X-ray absorption spectroscopy (XAS) has been revealed to be a potential tool for determining the electronic and geometrical structure of complex compounds. In particular, K edge and XANES spectra of transition metal complexes have been the topic of several studies. The position and shape of X-ray absorption discontinuities have been used to deduce structural and chemical bonding information on transition metal complexes. The K-absorption spectra were recorded on the synchrotron radiation, i.e., on beamline BL-8 at RRCAT, Indore. XANES reveal to identify the allowed transitions and also the mixing or splitting of the final state orbital. [1, 2] Using known structural data, informative deductions on structure-bonding relations have been made. copper K-edge XANES spectra have been used since they probe 1s→3d, 1s→4p transitions respectively. Since the spectra can be influenced by the state of the d orbital, which is primarily responsible for the bonding with ligands. For Cu-containing complexes, Cu K-edge XANES has been widely used to derive information on the electronic and geometrical structure. [ABSTRACT FROM AUTHOR]

A new soft x-ray beamline BL17SU (RIKEN) has been constructed at SPring-8. The beamline consists of two branches with each varied-line-spacing-plane-grating-monochromator. Both monochromators perform high energy resolution (E/ΔE > 10,000) between 0.2 and 1 keV. One of the monochromator achieves high energy stability of 10 meV over a period of half a day. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Singapore Synchrotron Light Source (SSLS) is commissioning its new beamline for Infrared Spectro/Microscopy (ISMI). The infrared light is extracted from the edge region of dipole D1 of the compact superconducting electron storage ring Helios 2. The nominal source point is located at half the maximum field, i.e., at 2.25 T. The end station comprises both, a medium and a high resolution Fourier transform infrared spectrometer (FTIR), the former featuring an infrared microscope as well as a UHV chamber for catalysis experiments. Synchrotron Radiation Workshop (SRW) calculations and a preliminary experimental evaluation of ISMI show the capability of this beamline to deliver a bright flux of photons in the Far and Mid infrared spectral regions. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The status of the soft x-ray beamline BL25SU at SPring-8 is reported. The beamline performance for circular dichroism measurements using the helicity switching of helical undulator radiation is focused on. Light spots on a sample of the opposite helicities have been observed with a photoelectron emission microscope. The vertical profiles of the spots have almost the same line shape and a positional difference of ∼ 0.5 μm. The horizontal spot positions coincide, but the horizontal spot widths are different by ∼ 7 %. The energy difference of the monochromatized light between the opposite helicities has been estimated to be less than or comparable to 1 meV in the Ne 1s absorption region. The kick angle of the kicker magnets has been increased from 0.2 to 0.3 mrad to avoid penetration of the higher harmonics. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The varied line spacing plane grating monochromator (VLS-PGM) has been constructed for an industry application beamline using soft x-rays from the 1.4 GeV storage ring in Saga, which is the first synchrotron in Kyushu Island. The design aim of the VLS-PGM is to cover the wide-energy range from 40–1,000 eV and also to have medium resolving power, high throughput, better reproducibility and suppression of higher-order light. In order to cover the wide energy range with suppressing higher-order light, a set of three focusing mirrors and one grating is installed. The resolving power expected from the ray-tracing calculation using SHADOW is more than 5,000 with 10 micron slits. The conventional photoelectron spectrometer is installed with an ion gun, a flood gun and a twin-anode x-ray source. The instrument for XAFS measurement is also attached to the main chamber. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The high-resolution absolute photoabsorption cross section with an absolute photon energy scale for Ne in the energy region of 864–872 eV (1s-1np Rydberg states) has been measured using a multi-electrode ionization chamber and monochromatized synchrotron radiation. The natural lifetime width of Ne 1s-13p resonance state has been obtained to be 252 ± 5 meV. The Ne+ (1s-1) ionization potential is determined to be 870.16 ± 0.04 eV by using the Rydberg formula. These absolute values are supposed to be more reliable than those previously reported. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

In soft X-ray energy region, there are really many absorption edges for the constituents of the useful materials. We have reported the powerful XAFS measurement system at soft X-ray energy beamline on small or compact storage ring HiSOR and also recent NEXAFS spectra data about nano, bio and catalytic materials. The XAFS measurement system has a Be window, which can separate the ultra-high vacuum (UHV) and the atmospheric pressure condition. Moreover the XAFS spectra can obtain by yielding a fluorescent X-ray emitted from the samples. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

In order to investigate photo-induced processes and dynamics of photochemical reactions involving molecular complexes and clusters in the vacuum ultraviolet and soft X-ray region, a cluster beam-photoreactive scattering apparatus has been designed and constructed at the HiSOR facility in Hiroshima University. The apparatus has a basic arrangement of a cluster beam source and a linear time-of-flight mass spectrometer, where it was designed to give strong cluster beam intensity enough to perform a variety of photoelectron and photoion coincidence measurements. Here, we present spectroscopic and coincidence measurements of the photo-induced processes of atomic and molecular clusters in the soft X-ray region to make a fundamental assessment for the present cluster beam-photoreactive scattering apparatus. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Recently, resolutions of energy and momentum in ARPES experiments have been greatly improved to 600∼700 μeV and 4×10-3 Å-1, respectively, at excitation photon energy of hv∼8 eV on helical undulator beamline connected to compact light source; HiSOR. During the experiments, temperature of specimens on multiaxis cryogenic manipulator can be controlled down to 4.8 K. The system has been applied to investigations of quasiparticles in high Tc superconductor and 3d transition metals. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Photodissociation process to produce the electronically excited CN(BΣ+) fragment has been studied for four structural isomers, n-C4H9CN, t-C4H9CN, n-C4H9NC and t-C4H9NC by using synchrotron radiation. Photoexcitation spectra for the CN(B2Σ+→X2Σ+) transition were measured in the excitation wavelength range of 85–165 nm (7.5–14.5 eV) and the CN(B2Σ+→X2Σ+) emission spectra were dispersed at several wavelengths in the range of 57–140 nm. Quantum yields for the production of the CN(B) state from photodissociative excitation of the isocyanides were larger than those from the cyanides. The quantum yields from the molecules consisting of tertiary-butyl group were larger than those from the normal-butyl compounds. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Annealing effect on the local structure of diamond like carbon (DLC) formed by focused ion beam-chemical vapor deposition (FIB-CVD) was investigated by the measurement of near edge x-ray absorption fine structure (NEXAFS) and energy dispersive x-ray (EDX) spectra. Carbon K edge absorption NEXAFS spectrum of FIB-CVD DLC was measured in the energy range of 275–320 eV. In order to obtain the information on the location of the gallium in the depth direction, incidence angle dependence of NEXAFS spectrum was measured in the incident angle range from 0° to 60°. The peak intensity corresponding to the resonance transition of 1s→σ* originating from carbon-gallium increased from the FIB-CVD DLC annealed at 200°C to the FIB-CVD DLC annealed at 400°C and decreased from that at 400°C to that at 600°C. Especially, the intensity of this peak remarkably enhanced in the NEXAFS spectrum of the FIB-CVD DLC annealed at 400°C at the incident angle of 60°. On the contrary, the peak intensity corresponding to the resonance transition of 1s→π* originating from carbon double bonding of emission spectrum decreased from the FIB-CVD DLC annealed at 200°C to that at 400°C and increased from that at 400°C to that at 600°C. Gallium concentration in the FIB-CVD DLC decreased from ≈2.2% of the as-deposited FIB-CVD DLC to ≈1.5% of the FIB-CVD DLC annealed at 600°C from the elementary analysis using EDX. Both experimental results indicated that gallium atom departed from FIB-CVD DLC by annealing at the temperature of 600°C. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The origin of amino acid formation in the early years is still not well known. Muñoz Caro and collaborators showed the generation of amino acid by UV irradiation of a mixture of organic molecules reproducing the interstellar media. Although the photochemistry is one of the mechanism which would be active in the early years, it is also important to study other mechanisms such as the electrochemistry or electron induced chemistry which would act as well as a tool for the amino acid formation. The aim of this work is to demonstrate the amino acid formation by low energy electron irradiation of condensed organic molecules. In particular, our purpose is the formation of glycine by low energy electron irradiation of a film composed of a mixture of condensed NH3 and CH3COOD. Prior to the study of amino acid formation it is important to know about the effect of the interaction between electrons and organic molecules, so the first step in this work is the study of the electron irradiation of NH3 and CH3COOD films condensed on a passivated substrate (hydrogenated diamond) at a temperature of about 40 K. The next step involves the electron irradiation of the condensed NH3 and CH3COOD mixture on the same substrate. In this case, the reactions induced by electron irradiation would permit the formation of glycine in the zwitterionic form. Induced modifications on the NH3 and CH3COOD molecules, as well as the formation of glycine will be monitored by High Resolution Electron Energy Loss Spectroscopy (HREELS). © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

After inner shell excitation the ultrafast fragmentation of small molecules can proceed on a time scale similar to that of the Auger decay. In this case the nuclear motion affects the observed electron spectrum in various ways. The best known example is the Doppler splitting of atomiclike Auger lines, but non-parallel potential surfaces are equally important. Using an electron energy — ion momentum coincidence experiment and an ab initio calculation of potential curves, we discuss the main features seen in the non-coincident and coincident resonant Auger spectrum by decay of the F(1s) → 6a* core excited state of CH3F. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Synchrotron radiation-excited etching of compound semiconductor, ZnTe, was investigated using the SF6 and Ar gases. In the case of SF6 gas, the ZnTe was not etched but thin film of a fluorine containing material, e.g. ZnF2, was deposited on the surface of ZnTe. On the other hand, ZnTe was etched by using Ar gas under the negative sample bias to the sample. The etched pattern obtained by placing a Ni mesh showed that only the irradiated area was etched. The etching rate was estimated to be around 4.5×10-2 Å/mA·min. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

A figure-8 undulator is installed in the soft X-ray beamline BL27SU at SPring-8 as insertion device. It provides linearly polarized light whose direction of polarization is horizontal for the integer order harmonic light and vertical for the half-integer order harmonic light. We have measured the degree of linear polarization of the monochromatic soft X-ray radiation at the end station of the beamline. Photoelectron spectra of Ne emitted in the horizontal direction are recorded for both horizontal and vertical directions of polarization, for two different settings of the front-end-slits. The degrees of linear polarization and the anisotropy parameters and branching ratios of photoelectrons are extracted in a self-consistent manner, at various photon energies. The resultant values for the degree of linear polarization are interpreted with the help of theoretical calculations. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The Varied Line Spacing Plane Grating Monochromator (VLSPGM) was adopted for industry application beamline at Saga-ring. The VLSPGM is consisted of three focusing mirrors and one grating to suppress the higher order and stray light in the wide energy range by changing the deflection angle. The parameters of varied line spacing grating were determined so as to satisfy the condition that the terms expressing defocus, coma and spherical aberrations in the optical path function are equal to zero. The overall performance of the VLSPGM was estimated using ray-tracing calculations. The calculated resolving power with the slit widths of 10 and 20 μm was more than 5,000 and 2,000 with the photon flux of more than 1×1010 and 6×1010 photons/sec/300mA, respectively. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The output energy and resolving power of a high-resolution monochromator are sensitive to temperature and vibrations of optical elements. Cooling of mirrors and gratings require: (1) to decreasing the velocity of cooling water with sufficient flow rate, (2) positioning devices to avoid distortion by cooling tube, and (3) maintaining an intimate contact with plates for exhausting heat. We have installed a cooling system that fulfills these essential conditions by using InGa in the monochromator of BL27SU, so that its energy drift is decreased to 10 meV for 6 hours. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Refocusing mirrors were designed and equipped in the high-resolution branch of BL27SU in SPring-8. It is required to switch quickly among the three tandem end-stations and achieve a vertical size of less than 10 microns at one experimental station. Two toroidal mirrors and a set of two cylindrical mirrors were employed in order to align them easily. The beam size and photon flux were measured. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

A new experimental setup for probing multi-electron processes in molecular inner-shell ionization regions has been developed at the UVSOR facility, IMS. A zero-kinetic-energy electron (ZEKE) analyzer is composed of a lens system on the basis of the penetrating field technique and an electrostatic analyzer. Two identical ion detectors with regarding grids are utilized for detecting the fragment-ions emitted at 0 and 90 degrees relative to the electric vector of the light, which correspond to the symmetry-resolved photoabsorption spectra. The symmetry-resolved ZEKE spectra have been measured by scanning the photon energy with monitoring the intensity of the coincidence signals between the ZEKE electrons and fragment-ions. The results obtained at SPring-8 using the new setup are reported. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

To study the influence of the flux ratio of C60 molecule to Ar cluster ion on DLC film characteristics, DLC films deposited under various flux ratios were characterized with Raman spectrometry and Near Edge X-ray Absorption Fine Structure (NEXAFS). From results of these measurements, hard DLC films were deposited when the flux ratio of C60 to Ar cluster ion was between 0.7 and 4. Furthermore the DLC film with constant sp2 content was obtained in the range of the ratio from 0.7 to 4, which contents are lower values than that of conventional films such as RF plasma. DLC films deposited under the ratio from 1 to 4 had hardness from 40 to 45GPa. It was shown that DLC films with stable properties of low sp2 content and high hardness were formed even when the fluxes were varied from 1 to 4 during deposition. It was indicated that this process was useful in the view of industrial application. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Near-edge X-ray absorption fine structure (NEXAFS) spectra were measured for the optimization of synthesis conditions on the production of diamond-like carbon (DLC) thin films by the Ar gas cluster ion beam (GCIB) assisted deposition of fullerene. The sp2 contents of DLC films were estimated from the analysis of the peak corresponding to the transition of the excitation electron from a carbon 1s orbital to a π* orbital in the NEXAFS spectrum of the carbon K-edge over the excitation energy range 275–320 eV. Substrate temperature and Ar cluster ion acceleration voltage in the synthesis conditions of DLC films were optimized to make the sp2 content minimum. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]