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Thin (<50 µm) and flawless diamond single crystals are essential for the realization of numerous advanced X-ray optical devices at synchrotron radiation and free-electron laser facilities. The fabrication and handling of such ultra-thin components without introducing crystal damage and strain is a challenge. Drumhead crystals, monolithic crystal structures composed of a thin membrane furnished with a surrounding solid collar, are a solution ensuring mechanically stable strain-free mounting of the membranes with efficient thermal transport. Diamond, being one of the hardest and most chemically inert materials, poses significant difficulties in fabrication. Reported here is the successful manufacture of diamond drumhead crystals in the [100] orientation using picosecond laser milling. Subsequent high-temperature treatment appears to be crucial for the membranes to become defect free and unstrained, as revealed by X-ray topography on examples of drumhead crystals with a 26 µm thick (1 mm in diameter) and a 47 µm thick (1.5 × 2.5 mm) membrane. [ABSTRACT FROM AUTHOR]

Leaf venation networks mediate many plant resource fluxes and are therefore of broad interest to research questions in plant physiology, systematics, paleoecology, and physics. However, the study of these networks is limited by slow and destructive imaging methods. X-ray imaging of leaf veins is potentially rapid, of high resolution, and nondestructive., Here, we have developed theory for absorption- and phase-contrast X-ray imaging. We then experimentally test these approaches using a synchrotron light source and two commercially available X-ray instruments., Using synchrotron light, we found that major veins could be consistently visualized using absorption-contrast imaging with X-ray energies < 10 keV, while both major and minor veins could be consistently visualized with the use of an iodine contrast agent at an X-ray energy of 33.269 keV. Phase-contrast imaging at a range of energies provided high resolution but highlighted individual cell walls more than veins. Both approaches allowed several hundred samples to be processed per d. Commercial X-ray instruments were able to resolve major veins and some minor veins using absorption contrast., These results show that both commercial and synchrotron X-ray imaging can be successfully applied to leaf venation networks, facilitating research in multiple fields. [ABSTRACT FROM AUTHOR]

One of the challenges of tuning bimorph mirrors with many electrodes is that the calculated focusing voltages can be different by more than the safety limit (such as 500 V for the mirrors used at 17-ID at the Advanced Photon Source) between adjacent electrodes. A study of this problem at 17-ID revealed that the inverse problem of the tuning in situ, using X-rays, became ill-conditioned when the number of electrodes was large and the calculated focusing voltages were contaminated with measurement errors. Increasing the number of beamlets during the tuning could reduce the matrix condition number in the problem, but obtaining voltages with variation below the safety limit was still not always guaranteed and multiple iterations of tuning were often required. Applying Tikhonov regularization and using the L-curve criterion for the determination of the regularization parameter made it straightforward to obtain focusing voltages with well behaved variations. Some characteristics of the tuning results obtained using Tikhonov regularization are given in this paper. [ABSTRACT FROM AUTHOR]

The aim of the study is to clarify how far it is possible to describe the mechanical behavior of novel TRIP-Steel/Mg-PSZ composite open-cell foam structures using beam networks generated from random tessellations. Conventional compression tests were performed with various foam samples. Furthermore, the deformation of open-cell composite foams was observed as well by X-ray computed tomography (XCT). Up to a compressive strain of 20% different stages of deformation could be observed. Respective bulk samples were manufactured by powder metallurgy and tested in order to determine the mechanical properties of the bulk material. Numerical simulations were employed based on the suitable modeling of foams exposed to mechanical loading. The predictions of the simulation are compared with the results of the deformation experiments. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the sap flow dynamics and xylem hydraulic properties is essential to unravel the functional features of water transport from roots to shoots in vascular plants. To evaluate quantitatively the safety and efficiency of this system, nondestructive methods to assess the interactions between sap ascent kinetics and xylem structure are required. In this study, synchrotron X-ray microscopy was employed to observe anatomical structures and sap flow dynamics in rice (Oryza sativa) xylem simultaneously. The phase-contrast imaging technique allowed nondestructive observation of the xylem structural characteristics and the air-water interfaces generated by dehydration-rehydration cycles in excised leaves. This X-ray microimaging method provided a unique tool to characterize the perforated end walls of vessel elements and to evaluate their influence on hydraulic resistance during the refilling of embolized vessels. The real-time monitoring of the axial and radial sap flow under various environmental conditions highlighted the important role of perforation plates. In summary, we report a new methodology to study the sap flow dynamics and xylem hydraulic properties with lm spatial and ms temporal resolution using X-ray microscopy. The experimental procedure described herein provides a useful handle to understand key sap transport phenomena in xylem. [ABSTRACT FROM AUTHOR]

LIGA process has been developed in the 2.5-dimensional world. We introduced new technologies of a 3D X-ray lithography and a worm injection molding with an unscrewing de-molding mechanism, and succeeded in the deployment of a 3D LIGA process. Furthermore, we fabricated a spiral microcoil using the 3D-LIGA process and a metallization technique combining flat and smooth electroplating and isotropic chemical etching. The microcoil diameter was 0.5 mm and the length was 1 mm. The width of coil lines was 10µm and the pitch was 20µm. Characteristics of this microcoil as an inductor combine the inductance of 91 nH and the quality factor of 5.8 at the frequency of 1 GHz. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(1): 43–51, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20679 [ABSTRACT FROM AUTHOR]

We have developed a new 3D X-ray lithography system for LIGA processing using synchrotron radiation at the New SUBARU facility of the University of Hyogo. The X-ray lithography system can utilize two different energy regions; one is a high-energy region from 3 keV to 10 keV, and the other is a low-energy region from 0.1 to 2 keV. Each energy region can be selected in accordance with the size and shape of the desired microstructures. It is demonstrated that a large-area high-luminance 7-inch optical waveguide for the liquid crystal backlight unit was successfully fabricated with this X-ray lithography method. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(1): 52–59, 2008; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/eej.20680 [ABSTRACT FROM AUTHOR]

The cost of searching for two visual targets simultaneously was compared against two separate single-target searches using exposure time and accuracy measures within a staircase procedure. Dual-target search for all stimuli (colour, shape and orientation) exhibited a loss of accuracy for one target. For orientation and shape, this dual-target cost in accuracy was extreme, with chance-level performance on one target. For colour, dual-target search exhibited an additional cost in search time, with search requiring a longer exposure than the summed time required for two single-target searches. An additional search-time cost was also found for orientation targets when irrelevant colour variation was added to the display. In conclusion, dual-target search for dissimilar targets is accompanied by an accuracy cost. Furthermore, colour variation, whether task-relevant or not, leads to an additional cost in processing speed. The results suggest that a divided-effort strategy would improve performance in search tasks such as X-ray baggage screening. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article investigates the phenomena of penetration of liquid slag into solid bulk lime and into the cracks of the lime body with the use of in-situ X-ray direct observation. It was found from the immersion experiments that the height of slag penetration into the lime bulk was linearly proportional to the penetration time and the rate of penetration at high temperature is much greater than in low temperature.

There have been efforts to detect the collimation field of medical digital radiographs (x-ray images), which is unnecessary in diagnosis. The method used in past studies is to detect the boundary of the collimation field as a straight line, using the edge detection on the two-dimensional image. The boundary, however, is not an ideal step-edge, as is seen from the principle of image generation, but is a ramp edge containing a blur (half-shadow). This paper extends the radiograph to another dimension of brightness, to be considered as three-dimensional data. A method is proposed in which the Hough transform is used to detect the boundary of the collimation field as a plane. In order to investigate the validity of the model and the effectiveness of the proposed method, a detection experiment is performed for the collimation field. The collimation field is correctly detected at a rate of 96.4% (324 cases) in 336 images. It is also shown that when the image is compressed by setting the brightness of the detected collimation field as 0, the amount of image data is smaller than the amount of image data obtained by compressing the original image. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(6): 22–33, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20268 [ABSTRACT FROM AUTHOR]

Simulation results for four MEMS variable capacitors suitable for fabrication using the LIGA process are presented. A Q-factor as high as 435.6 was obtained using a copper-device layer. The capacitor with a nominal capacitance of 0.24 pF has a self-resonant frequency of 33.7 GHz, making it suitable for operation up to frequencies of approximately 18 GHz. Using a “pull-away” actuation design, a tuning ratio of 1.43:1 was obtained with tuning voltages as low as 6.1 V. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 507–511, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20352 [ABSTRACT FROM AUTHOR]

Pretinning of gold-plated components is often done to avoid the formation of brittle Au/Sn intermetalli&cgrave; compounds, which may lower the mechanical strength of the joints. In this investigation the reliability of 32LCCs surface mounted on alumina boards is tested in internal and external temperature cycling, as well as in shear tests, and the effect of pretinning is studied. One thousand times of temperature cycling between -55 and + 125°C and 2000 h of power cycling with an upper joint temperature of + 75°C did not cause any electrical opens. Shear tests made after a 168 h heat treatment at + 125°C and 1000 temperature cycles showed that forces of approximately 1000 N were required to break the chip carrier joints. The microstructure of Sn62/Pb36/Ag2 solder joints containing gold was examined and the existing phases were identified using electron diffraction X-ray analysis. The joints fail at the Au/Sn intermetallics at the chip carrier metallization or at the Cu/Sn compounds formed at the substrate thick film/solder interface. No deterioration of the overall joint strength due to Au/Sn intermetallics was seen, when the gold content in the joints was approximately 4 weight per cent. [ABSTRACT FROM AUTHOR]

Scope of Deliverables: This section reviews current applications of X-ray technology for food processing. The advantages of X-rays over other types of radiation are described. A study on the inactivation of Escherichia coli, a pathogen of concern, with pulsed X-rays in ground meat is described. Little is known about the inactivation kinetics when X-rays or pulsed X-rays are used for microbial inactivation. Comprehensive research needs to be done to validate the potential use of X-rays in food preservation. [ABSTRACT FROM AUTHOR]