Tuning the electronic band structure of PCBM by electron irradiation

Tuning the electronic band structures such as band-edge position and bandgap of organic semiconductors is crucial to maximize the performance of organic photovoltaic devices. We present a simple yet effective electron irradiation approach to tune the band structure of [6, 6]-phenyl-C61-butyric acid methyl ester (PCBM) that is the most widely used organic acceptor material. We have found that the lowest unoccupied molecular orbital (LUMO) level of PCBM up-shifts toward the vacuum energy level, while the highest occupied molecular orbital (HOMO) level down-shifts when PCBM is electron-irradiated. The shift of the HOMO and the LUMO levels increases as the irradiated electron fluence increases. Accordingly, the band-edge position and the bandgap of PCBM can be controlled by adjusting the electron fluence. Characterization of electron-irradiated PCBM reveals that the variation of the band structure is attributed to the molecular structural change of PCBM by electron irradiation

Toxicity Studies on Secretio Bufonis: A Traditional Supplement in Asia

AbstractObjectivesThis study was performed to investigate the toxicity of Secretio Bufonis (SB) on male mice and assess its no-observed-adverse-effect-level (NOAEL).Materials and MethodsAfter feeding an aqueous solution of SB extracts to mice for either 1 or 8 weeks, their blood and urine were assayed and their liver and kidney morphology examined. The numerical data was analyzed by the Mann-Whitney U-test and analysis of variance test.ResultsMice administered SB in 50 mg/kg/day for 1 week had higher heart weights and higher aspartate transaminase activities; those administered SB in 0.01 and 0.05 mg/kg/day for 8 weeks had lower creatinine concentrations; and those administered SB in 0.5 mg/kg/day for 8 weeks had higher brain weights and higher blood urea nitrogen.ConclusionsThe extracts of SB had cardiac toxicity in the short term and hepatotoxicity in the long term. The NOAEL of the extract was under 5 mg/kg/day for 1 week and under 0.25 mg/kg/day for 8 weeks

Improved conversion efficiency of Ag2S quantum dot-sensitized solar cells based on TiO2 nanotubes with a ZnO recombination barrier layer

We improve the conversion efficiency of Ag2S quantum dot (QD)-sensitized TiO2 nanotube-array electrodes by chemically depositing ZnO recombination barrier layer on plain TiO2 nanotube-array electrodes. The optical properties, structural properties, compositional analysis, and photoelectrochemistry properties of prepared electrodes have been investigated. It is found that for the prepared electrodes, with increasing the cycles of Ag2S deposition, the photocurrent density and the conversion efficiency increase. In addition, as compared to the Ag2S QD-sensitized TiO2 nanotube-array electrode without the ZnO layers, the conversion efficiency of the electrode with the ZnO layers increases significantly due to the formation of efficient recombination layer between the TiO2 nanotube array and electrolyte

Fabrication of complete titania nanoporous structures via electrochemical anodization of Ti

We present a novel method to fabricate complete and highly oriented anodic titanium oxide (ATO) nano-porous structures with uniform and parallel nanochannels. ATO nano-porous structures are fabricated by anodizing a Ti-foil in two different organic viscous electrolytes at room temperature using a two-step anodizing method. TiO2 nanotubes covered with a few nanometer thin nano-porous layer is produced when the first and the second anodization are carried out in the same electrolyte. However, a complete titania nano-porous (TNP) structures are obtained when the second anodization is conducted in a viscous electrolyte when compared to the first one. TNP structure was attributed to the suppression of F-rich layer dissolution between the cell boundaries in the viscous electrolyte. The structural morphologies were examined by field emission scanning electron microscope. The average pore diameter is approximately 70 nm, while the average inter-pore distance is approximately 130 nm. These TNP structures are useful to fabricate other nanostructure materials and nanodevices

Improvement in the photoelectrochemical responses of PCBM/TiO2 electrode by electron irradiation

The photoelectrochemical (PEC) responses of electron-irradiated [6,6]-phenyl-C61-butyric acid methyl ester (PCBM)/TiO2 electrodes were evaluated in a PEC cell. By coating PCBM on TiO2 nanoparticle film, the light absorption of PCBM/TiO2 electrode has expanded to the visible light region and improved the PEC responses compared to bare TiO2 electrode. The PEC responses were further improved by irradiating an electron beam on PCBM/TiO2 electrodes. Compared to non-irradiated PCBM/TiO2 electrodes, electron irradiation increased the photocurrent density and the open-circuit potential of PEC cells by approximately 90% and approximately 36%, respectively at an optimum electron irradiation condition. The PEC responses are carefully evaluated correlating with the optical and electronic properties of electron-irradiated PCBM/TiO2 electrodes

Distribution and Conservation of Long-billed Plovers Charadrius placidus in Korea

AbstractThe Long-billed Plover Charadrius placidus of distribution was surveyed from 2002 to 2005, on rivers, streams and coasts of 38 areas within Korea. The Sum of highest numbers (sum of peak counts) of Long-billed Plovers at 24 sites was 198 individuals. Number of observed individuals during breeding period was 88 individuals, 129 individuals during the migration period, and 56 individuals during the wintering period. The Long-billed Plover breeds and migrates throughout Korea. They spend winter south of 37° latitude. Highest numbers (73 individuals) were observed at Daejeon. Therefore, streams and rivers of Korea are considered as an important habitat for the Long-billed Plover

Accuracy and Efficacy of Ultrasound-Guided Pes Anserinus Bursa Injection

The term “pes anserinus tendinobursitis (PATB)” is generally used to describe the inflammatory condition of pes anserinus bursa (PAB). Ultrasound (US) is widely used as a diagnostic and therapeutic tool to improve the assessment and management of joints and soft tissues. We performed the study to prove the accuracy and efficacy of US-guided injections in patients with PATB by comparing blind interventions. Forty-seven patients were randomly assigned to an US-guided and a blind injection group. The patients in the US-guided group were given injections under sonographic visualization. Otherwise, in the blind group, injections were provided in the conventional technique without any sonographic guidance. After the management, the accuracy of the injections was assessed by identifying the injectate location using the US. Treatment efficacy was evaluated using the visual analog scale (VAS) of knee tenderness. The US-guided group showed that the injectates were located at the PAB accurately in all participants, whereas the blind group revealed that the materials were found to be at the bursa side only in 4 out of 22 patients. VAS scores of the US-guided group significantly improved compared to the blind group. In conclusion, US-guided PAB injections are more accurate and efficacious than blind approaches

Cancer-related Fatigue in Patients with Advanced Cancer Treated with Autonomic Nerve Pharmacopuncture

AbstractThe purpose of this study was to observe the effects of autonomic nerve pharmacopuncture (ANP) treatment on cancer-related fatigue (CRF) in patients with advanced cancer. This observational case study was conducted at the East West Cancer Center of Daejeon University's Dunsan Korean Medical Hospital. Two patients were observed. One patient was diagnosed with left thymic cancer metastatic to the left pleura. The other patient had terminal-stage cervical cancer with iliac bone and lumbar 5 metastases. We injected mountain ginseng pharmacopuncture (MGP) into acupoints alongside the spine (Hua-Tuo-Jia-Ji-Xue, EX B2). We examined the patients for CRF using the Korean version of the Revised Piper Fatigue Scale (RPFS-K), which is a self-assessment tool. The scores on the RPFS-K for both patients tended to decrease during the treatment. Laboratory findings, including hematological changes, were also checked. Liver and renal function tests showed that the treatment was safe. Although further large-population studies are necessary, this case study suggests that ANP has a favorable effect on CRF in patients with advanced cancer