RESUMEN
Efficient room temperature NIR detection with sufficient current gain is made with a solution-processed networked SWNT FET. The high performance NIR-FET with significantly enhanced photocurrent by more than two orders of magnitude compared to dark current in the depleted state is attributed to multiple Schottky barriers in the network, each of which absorb NIR and effectively separate photocarriers to corresponding electrodes.
RESUMEN
BACKGROUND: Belt or wire shaped TiO2(B) particles were synthesized for lithium ion battery application by a hydrothermal and heat treatment process. In order to facilitate TiO2(B)/C composites fabrication, the synthesized TiO2(B) particles were crushed into smaller sizes by ball milling. RESULTS: Ball mill treated TiO2(B) particles of less than 1.0 µm with a fraction of anatase phase, compared to as-synthesized TiO2(B) particles with about 24 µm in average particle size, showed a significant improvement in the electrochemical properties. They showed a much improved stability in the charge-discharge cycles and irreversibility. They maintained about 98% of the initial capacity during 50 cycles while as-synthesized sample before ball mill treatment showed a gradual decrease in the capacity with the cycles. The irreversibility of 12.4% of as-synthesized sample was also greatly improved to 7% after ball milling treatment. CONCLUSIONS: Our results indicate ball mill treatment can be an economical way to improve electrochemical properties of TiO2(B) anode materials for lithium ion battery application.
RESUMEN
The collapse of North Korea's public health system has increased the development of tuberculosis (TB) in its populace. This study investigated the prevalence of active and latent TB infection (LTBI) in such people who have settled in the Republic of Korea since 1999. From 1999 to August 2006, 7,722 dislocated North Koreans entered the Republic of Korea and all were screened immediately for active TB. Demographic and clinical characteristics were reviewed from the official records of the Settlement Support Office for Dislocated North Koreans, based in the Ministry of Unification. Of 7,722 participants, 87 (1.13%) were diagnosed with active TB from 1999 to August 2006. Of these, 78 (90%) had pulmonary TB. Checking for the presence of a Bacille Calmette-Guerin (BCG) scar and tuberculin skin test has been performed in all dislocated North Koreans since November 2005. Of 1,112 participants, BCG vaccination scars were found in 67.4%. The tuberculin-positive rate using two tuberculin unit doses of the purified protein derivative RT23 (> or =10 mm in diameter) was 81.5%. The prevalence of active TB and LTBI in dislocated North Koreans was high. Because this group bears a disproportionate burden of TB, we need to initiate a specific control programme and to plan for the impact of this disease in the Republic of Korea.