Bacillus pasteurii was used as synthesis director for the formation of hollow cylinder and helical NiO micro/nanostructure under urea hydrolysis conditions. Bacteria were capable of precipitating nickel product from nickel solution by metabolic processes. An appropriate amount of both water and bacterial solution were required to precipitate the nickel product in good yield. The average crystallite size of NiO was 11.45 nm and lengths of the cylinder and helices were non-uniform (~2–7 µm) and were varied with bacterial body structure template. The present study demonstrates a feasibility of synthesizing bacteria-guided metal oxide crystals for various functional applications.

We report herein the crystal growth of ZnO nanoparticles by the foam fractionation method. In this study, the vertical column height of the foam was fixed and the velocity of the sparging air was varied, and the effect of foam flow rate on the synthesis of ZnO was investigated. The obtained ZnO consisted of aggregated platelets and had differing ultraviolet absorbances. The as-synthesized ZnO was hydrophobic because of the interaction between the anionic head groups of sodium dodecyl sulfate (SDS) and the ZnO under the precipitation conditions. The long chain of the SDS molecule was the cause of hydrophobicity. The contact angle of water was in the range of 95–105° for the obtained ZnO/SDS surface. The photocatalytic degradation efficiency of the as-synthesized (ZnO/SDS) and the calcined ZnO was investigated for methylene blue, and the calcined ZnO retained its activity even after three recycles.

We investigated a cluster of postoperative febrile episodes and episodes of Acinetobacter baumannii bacteremia in obstetrics and gynecology wards after an electrical blackout and loss of the water supply. The use of patient-controlled analgesia was the only independent risk factor associated with postoperative fever, and A. baumannii isolates recovered from the blood of patients who had received patient-controlled analgesia were genetically related to an isolate recovered from the diluted morphine solution used for this procedure. After inappropriate preparation of the morphine solution was identified and stopped, the outbreak ended.

We report two cases of carcinoma in situ in the external auditory canal (EAC), presenting with symptoms such as pain, long-term itching of the ear, easy contact bleeding, canal otorrhea and hearing loss. Otoscopic examination revealed granulation tissue and a greyish-black tumour with irregular surface. The first patient had previously been diagnosed with otitis externa with persistent ear itching for the past three years. The second patient had received tympanoplasty for treatment of chronic otitis media on the right ear ten years ago. The first case was treated with wide excision, whereas the second patient received resection of the skin of the EAC together with its adjacent soft tissue, followed by skin grafting. No tumour recurrence was noted in the fourth and third post-operative year for the first and second patient respectively. We suggest that EAC carcinoma can be detected early and treated.

Recently, it was reported that adding Zn to solder was an effective way for reducing the formation of both Cu3Sn and Cu6Sn5 and inhibiting Kirkendall voids formation. The objective of this study is to investigate this Zn effect in detail. Three Sn-xZn solders (x = 0.5, 0.7, and 2 wt. %) were reacted with Cu substrates at 250°J for 2-10 mins. A slight variation in the Zn concentration changed the reaction product formed at the interface. When the Zn concentration was low (x = 0.5 wt. %), the reaction product was Cu6Sn5. At high Zn concentration (x = 2 wt. %), the reaction product became Cu5Zn8. When Zn concentration was in-between (x = 0.7 wt. %), Cu6Sn5 and CuZn co-existed. The above findings are explained using the Cu–Sn–Zn phase diagram. The implication is that the type of compound forms at the interface can be controlled by adjusting the Zn concentration of the Sn-based solders.

Spalling of intermetallic compounds in a massive scale has been reported in the literature for several solder/substrate systems, including SnAgCu soldered on Ni substrate, SnZn on Cu, high-Pb PbSn on Cu, and high-Pb PbSn on Ni. In this work, a common mechanism based on thermodynamic arguments is proposed to explain this rather peculiar phenomenon that occurs across several systems. According to this mechanism, two necessary conditions must be met. This first is that the most reactive element must be present in a limited amount, and the second is that the soldering reaction must be very sensitive to the concentration of this element. With the growth of intermetallic, more and more of the most reactive elements are extracted out of the solder and incorporated into intermetallic. As the concentration of this element decreases, the local equilibrium phase at the interface changes. This changing of the equilibrium phases caused the non-equilibrium phase to spall.

Ink jet technology is applied to the industry application of CPU cooling in this study. The PZT actuated micro-cooling device which generating the micro-scale liquid droplet is used in the CPU cooling of desktop and laptop PCs. It consists the advantages of long lifetime of operation, simple and easily manufactured of the structure with PZT actuator. Since the high latent heat transfer rate, 2260 J/g, of water droplet for the liquid-vapor phase change cooling system, it removes heat from the CPU surface effectively for over 100 W. In order to design an efficient cooling device, it is important to study the PZT material property varies after the laser cutting process and the dimensional effects of PZT actuator on the nozzle plate vibration mode. The frequency and amplitude of the voltage used to energize the PZT transducer are also important parameters that should be properly controlled in order to achieve the optimal liquid breakup conditions. It also reveals the low noise and power consumption in the CPU cooling system with some appropriate operational conditions.