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It is vital to create flexible batteries as power sources to suit the needs of flexible electronic devices because they are widely employed in wearable and portable electronics. The direct methanol fuel cell (DMFC) is a desirable alternative portable energy source since it is a clean, safe, and high energy density cell. The traditional DMFC in mechanical assembly and its unbending property, however, prevent it from being employed in flexible electrical devices. In this study, the flexible membrane electrode assembly (MEA) with superior electrical conductivity and nanoscale TiC-modified carbon cloth (TiC/CC) is used as supporting layer. Additionally, solid methanol fuels used in the manufacturing of flexible all-solid-state DMFC have the advantages of being tiny, light, and having high energy density. Furthermore, the DMFC's placement and bending angle have little effect on its performance, suggesting that DMFC is appropriate for flexible portable energy. The flexible all-solid-state DMFC's power density can reach 14.06 mW cm-2 , and after 50 bends at 60°, its voltage loss can be disregarded. The flexible all-solid DMFC has an energy density that is 777.78 Wh Kg-1 higher than flexible lithium-ion batteries, which is advantageous for the commercialization of flexible electronic products.
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In this paper, ß-Ga2O3 nanowires were synthesized by vapor transport method at different temperatures. The as-prepared samples were analyzed for crystal structure by X-ray diffraction (XRD), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), and for morphology using scanning electron microscopy (SEM). The results show that the Ga2O3 nanowires present a monoclinic structure, the length and diameter of the Ga2O3 nanowires increased with the growth temperature. A majority of the Ga2O3 nanowires present longitudinal twinning structures. A broad photoluminescence emission band was observed from the Ga2O3 nanowires at room temperature, which is caused by different kinds of vacancy defects. Our study shows an unusual twinning structure of ß-Ga2O3 nanowires, which may be helpful to understand the growth mechanism of nanowires.
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AIM: To evaluate the feasibility and safety of No. 13 lymphadenectomy in radical gastrectomy for gastric carcinoma. METHODS: Medical records of the patients undergone No. 13 lymph node dissection during D2 gastrectomy for gastric carcinoma, were reviewed from March 2003 to May 2007. RESULTS: One hundred and fifty-eight patients underwent No. 13 lymph node dissection for D2 gastric carcinoma, of them, 4 (2.53%) were found to have metastasis in No. 13 lymph node. Metastasis to No. 12 lymph node was detected in 6 patients and 4 of them had positive No. 13 lymph node. The operative morbidity except for wound infection was 15.19% (24/158), and hospital death rate was 1.27% (2/158). No obstructive jaundice caused by No 13 lymph node metastasis after No. 13 lymph node dissection in radical gastrectomy for gastric carcinoma was detected during the follow-up study to end of January 2007. CONCLUSION: Dissection of No. 13 lymph node in D2 gastrectomy for gastric carcinoma is safe with a low morbidity and mortality rate. Further study is needed to explore its long-term effect.
Assuntos
Gastrectomia , Excisão de Linfonodo , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Ulva prolifera can protect human skin fibroblast from being injured by hydrogen peroxide. This work studied the composition of Ulva prolifera polysaccharide and identified its physicochemical properties. The results showed that the cell proliferation of 0.5mg/mL crude polysaccharide was 154.4% of that in negative control group. Moreover, ROS detection indices, including DCFH-DA, GSH-PX, MDA and CAT, indicated that crude polysaccharide could improve cellular ability to scavenge free radical and decrease the injury on human skin fibroblast by hydrogen peroxide. In purified polysaccharide, the activity of fraction P1-1 was the highest, with 174.6% of that in negative control group. The average molecular weight of P1-1 was 137kD with 18.0% of sulfate content. This work showed the inhibition of hydrogen peroxide induced injuries on human skin fibroblast by Ulva prolifera polysaccharide, which may further evaluate the application of U. prolifera on cosmetics.