摘要:

A Protein crystallography beam line using MIRRORCLE‐6X, which is a compact synchrotron for hard x‐ray production, is under construction. Since MIRRORCLE‐6X provides hard x‐ray with high brightness, it is suitable for x‐ray source of accurate protein crystallography research in a small laboratory.The divergent x‐ray emitted from a target is focused by a condensing mirror. The mirrors used for the condensing mirror are a multi layer mirror of Wolter type and a rotating ellipsoidal mirror. Photon energies dispersed by them are set to the K‐edge of Zn and of Se, respectively. The flux at a focusing point is expected to be 103∼ 104times larger than that without the condensing mirror. The focusing size is less than 100 &mgr;m of diameter. The x‐ray after the mirror is transformed to parallel beam using a Fresnel zone plate and irradiated on a protein crystal. The diffraction figure is detected by the an imaging‐plate detector. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1796601

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

Microfocusing experiments of high‐brilliance, high‐energy X‐ray by using a multilayer Fresnel zone plates were performed at SPring‐8. It is proved that the multilayer FZPs can be used as focusing elements with high spatial resolution in a wide range X‐ray wavelength domain up to 100 keV. A Cu/Al FZP with the thickness of 40 micron has attained the spatial resolution of 0.7 ∼ 1.8 micron in a wide range X‐ray wavelength domain of 18.6 ∼ 113 keV. Three types of microscopic image of an Au mesh with 1500 lines per inch were taken by a X‐ray microscopy experiment by using the multilayer FZP at 82 keV: a scanning microscopic transmission image, a scanning microscopic fluorescent one and an imaging microscopic one with the spatial resolution of ∼ 0.7 micron. High‐energy X‐ray microprobe by using the multilayer FZP will be powerful tool for non‐destructive various analyses of thick materials (bulk, IC, etc) with submicron spatial resolution. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1796602

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

X‐ray microscopy enables high‐resolution analysis of thick specimens such as several microns in aqueous and atmospheric pressure environments in fields of biological and material sciences. Most commonly, zone plates (ZPs) are used as optical elements in combination with the use of synchrotron radiation (SR) as an x‐ray source. It is realized at the x‐ray microscopy station at BL‐12 of Ritsumeikan University SR center. The highest spatial resolution is 50 nm. The beam line is open to researchers from universities, government research centers and companies and has been applied in biology, medicine, and material science. The present paper describes a recent progress and recent results of BL12. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1796603

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

A new high resolution X‐ray microscopy project is proposed at Saga synchrotron light source, a third generation synchrotron light facility in Kyusyu Island, Japan. Two microscopy beamlines are planned. One is a scanning microscope in the water window region and the other is a full‐field imaging microscope in the multi‐keV X‐ray energy region. To demonstrate the feasibility of the project, an optical layout of the scanning microscope was designed. The beamline mainly consists of a 3.5 cm periodical undulator, a varied line‐spacing plane grating monochoromator (600 lines/mm) and an end‐station including a zone plate. The calculated X‐ray properties focused on the sample position are as follows: the spot size is ∼70 nm, the monochromaticity is ∼2000, and the photon flux is 109∼ 1010photons/s. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1796604

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

X‐ray Talbot Interferometry (XTI) is demonstrated as a novel and simple X‐ray phase‐sensitive imaging method. Differential phase contrast is generated with XTI and quantitative determination of the differential phase is attained in combination with a phase‐shifting technique, further enabling phase tomography. Because XTI does not use crystals but transmission gratings, divergent X‐rays with a broad energy band are available. This is an advantage for medical applications especially using a compact X‐ray source. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1796605

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

Monochromatic x‐ray CT at two different energies provides information about electron density without ambiguity due to the beam hardening effect. This information makes the treatment planning for heavy‐ion radiotherapy more precise. We have started a feasibility study on the dual‐energy x‐ray CT by using synchrotron radiation. We developed a linear scanning CT system in order to evaluate what precision in the measurement was achieved. The experiments were carried out using monochromatic x‐rays of 40, 70 and 80 keV. Comparison of measured electron densities with the theoretical values proved that these values were in agreement in 0.9 &percent; on average. We have developed a 2D‐CT system with a two‐dimensional scintillator array to take images in a short time. At present, it has been proved that the electron density is measured in the precision of about 1 &percent; with the 2D‐CT system. Effective atomic numbers are obtained as well from the dual‐energy x‐ray CT. The CT images are reconstructed based on each of the electron density and the effective atomic number. They present different features of an object, and the contrasts in the images differ from that in a conventional CT image. The feature of the images may help distinguish more clearly tissues or organs with aid of different contrast from the conventional CT images. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1796606

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

Non‐thermal effects of millimeter wave (MMW) on Pheochromocytoma (PC12) were studied by potential measurement with a voltage sensitive dye (DiBAC4(3)). Cells were irradiated at fixed frequencies of 30, 40, 60, 76GHz as well as sweeping frequency between 10 and 100 GHz by an MMW generator based on a uni‐traveling‐carrier photodiode (UTC‐PD), the most widely tunable MMW source. However there were no significant changes in membrane potential between MMW‐irradiated and control cells. The results suggest that MMW irradiation in the range from 10 to 100GHz appears to be safe for ordinary PC12 cells under non‐thermal conditions. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1796607

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

The recent progress in the portable synchrotron MIRRORCLE‐20 for brilliant FIR or IR source for the life Science research is reported. The new MIRRORCLE‐20 FIR beam line is consist of the special optics which collect all radiation, emitted from the exactly circular 156mm radius electron orbit, by using both circular mirror and quasi‐ellipsoidal mirror (magic mirror). The optics designed is somewhat different from the conventional SR beam line optics. In case the whole radiation is collected and the e‐beam lifetime reaches 1 minute, 10W power in total are available. The beam line was tuned to maximize the light extraction. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1796608

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

Portable synchrotron, MIRRORCLE 20 in Ritsumeikan University is prepared as the infrared and far infrared synchrotron light source for the molecular dynamics study. The FTIR spectrometer and the dispersive‐type IR irradiation system using grating monochrometer are installed in the beam line. Sample cells with a temperature controller is prepared for the FTIR measurements of water‐rich samples like the aqueous solution, which encounters difficulty in a conventional FTIR system. The irradiation system provides monochromatic IR‐rays in the wave length between 2&mgr;m and 25&mgr;m. Dielectric relaxation spectroscopy (DRS) with network analyzer in the frequency range of 45MHz to 20GHz is prepared for the measurements of the sample irradiated by monochromatic IR‐rays. Research plans with the analysis system for dynamical water structure is described in this report. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1796609

出版商:AIP    

年代:1904

数据来源: AIP

摘要:

In this article, partial molar volumes of hydrophobic compounds in water were reviewed. Distorted surfaces of the partial molar volumes for alkylbenzenes in water were drawn in a wide range of pressure, 0.10–400 MPa, and temperature, 273–323 K. They include a domain of negative compressibility of the partial molar volume in a low temperature and low pressure region. The negative compressibility was ascribed to a well‐known property of bulk water; more compressible at lower temperature in the observed region. Aromatic ring which was included in naphthalene, anthracene, etc. contribute to the positive sign of the volume change for hydrophobic hydration though the negative sign has been usually observed for a methylene group of many hydrophobic compounds. © 2004 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1796610

出版商:AIP    

年代:1904

数据来源: AIP