The technique used to align liquid crystals-rubbing the surface of a substrate on which a liquid crystal is subsequently deposited-has been perfected by the multibillion-dollar liquid-crystal display industry. However, it is widely recognized that a non-contact alignment technique would be highly desirable for future generations of large, high-resolution liquid-crystal displays. A number of alternative alignment techniques have been reported, but none of these have so far been implemented in large-scale manufacturing. Here, we report a non-contact alignment process, which uses low-energy ion beams impinging at a glancing angle on amorphous inorganic films, such as diamond-like carbon. Using this approach, we have produced both laptop and desktop displays in pilot-line manufacturing, and found that displays of higher quality and reliability could be made at a lower cost than the rubbing technique. The mechanism of alignment is explained by adopting a random network model of atomic arrangement in the inorganic films. Order is induced by exposure to an ion beam because unfavourably oriented rings of atoms are selectively destroyed. The planes of the remaining rings are predominantly parallel to the direction of the ion beam.

Electromigration induced damage strongly depends on Sn-grain orientation in Pb-free solders. Rapid depletion of intermetallic compounds and under bump metallurgy led to significant damages caused by the fast diffusion of Cu and Ni along the c axis of Sn crystals. When the c axis of Sn grain is not aligned with the current direction, electromigration (EM) damage is dominated by Sn self-diffusion, which takes longer to occur. This is a direct proof of the highly anisotropic diffusion behavior in Sn. Due to the presence of twin structures and stable Ag3Sn network, SnAg(Cu) solders are less susceptible to grain orientation effects and showed better EM performance than SnCu solders.

3D ultrasound is a promising imaging modality for clinical diagnosis and treatment monitoring. Its cost is relatively low in comparison with CT and MRI, no intensive training and radiation protection is required for its operation, and its hardware is movable and can potentially be portable. In this study, we developed a portable freehand 3D ultrasound imaging system for the assessment of musculoskeletal body parts. A portable ultrasound scanner was used to obtain real-time B-mode ultrasound images of musculoskeletal tissues and an electromagnetic spatial sensor was fixed on the ultrasound probe to acquire the position and orientation of the images. The images were digitized with a video digitization device and displayed with its orientation and position synchronized in real-time with the data obtained by the spatial sensor. A program was developed for volume reconstruction, visualization, segmentation and measurement using Visual C++ and Visualization toolkits (VTK) software. A 2D Gaussian filter and a Median filter were implemented to improve the quality of the B-scan images collected by the portable ultrasound scanner. An improved distance-weighted grid-mapping algorithm was proposed for volume reconstruction. Temporal calibrations were conducted to correct the delay between the collections of images and spatial data. Spatial calibrations were performed using a cross-wire phantom. The system accuracy was validated by one cylinder and two cuboid phantoms made of silicone. The average errors for distance measurement in three orthogonal directions in comparison with micrometer measurement were 0.06+/-0.39, -0.27+/-0.27, and 0.33+/-0.39 mm, respectively. The average error for volume measurement was -0.18%+/-5.44% for the three phantoms. The system has been successfully used to obtain the volume images of a fetus phantom, the fingers and forearms of human subjects. For a typical volume with 126 x 103 x 109 voxels, the 3D image could be reconstructed from 258 B-scans (640 x 480 pixels) within one minute using a portable PC with Pentium IV 2.4 GHz CPU and 512 MB memories. It is believed that such a portable volume imaging system will have many applications in the assessment of musculoskeletal tissues because of its easy accessibility.

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We fabricated pure and SiC-added MgB 2 /Fe composite tapes using a MgH 2 starting powder and applying heat treatments at 600-900 • C and systematically investigated their superconducting properties. For both the pure and SiC-added tapes, the critical temperature (T c ) increased with increasing heat-treatment temperature due to the improved crystallinity of MgB 2 . The SiC addition decreased the T c but increased the slope of the B c2 -T and B irr -T curves, dB c2 /dT and dB irr /dT , for all heat-treatment temperatures. The dB c2 /dT and dB irr /dT of the pure tape decreased with increasing heat-treatment temperature from 600 to 700 • C because of the longer coherence length associated with the improved crystallinity. However, the SiC addition significantly decreased the heat-treatment temperature dependences of dB c2 /dT and dB irr /dT . At a temperature of ∼20 K, which is easily obtained using a cryocooler, the B irr is governed by both the T c and dB irr /dT . The B irr of a pure tape at 20 K decreased with increasing heat-treatment temperature from 600 to 700 • C, but the B irr of the 10 mol% SiC-added tape increased with the temperature. These behaviours can be explained by the heat-treatment temperature dependence of the T c and dB irr /dT . At 20 K the highest B irr of 10 T was obtained under the conditions of a 10 mol% SiC addition and heat-treatment temperature of 900 • C. This B irr at 20 K is comparable to that of commercial Nb-Ti at 4.2 K. The 10 mol% SiC-added tape heat treated at 900 • C and the 5 at.% SiC-added tape heat treated at 800 • C showed J c (MgB 2 core) values higher than 10 4 A cm −2 at 20 K in 5 T.