In this letter, an efficient method for the photolytic generation of difluoromethyl radicals from [bis(difluoroacetoxy)iodo]benzene reagents is described. The present approach enables the introduction of difluoromethyl groups into various heteroarenes under mild conditions in the absence of any additional reagents or catalysts.

The purpose of this study was to retrospectively investigate the feasibility of 11 C-choline PET, compared with 18 F-FDG PET, for the detection of hepatocellular carcinoma (HCC). Methods: A total of 16 HCC lesions in 12 patients were examined with both 11 Ccholine PET and 18 F-FDG PET. Tumor lesions were identified as areas of focally increased uptake, exceeding that of surrounding noncancerous liver tissue. For semiquantitative analysis, the tumor-to-liver (T/L) ratio was calculated by dividing the maximal standardized uptake value (SUV) in HCC lesions by the mean SUV in noncancerous liver tissue. Results: 11 C-choline PET showed a slightly higher detection rate than did 18 F-FDG PET for detection of HCC (63% vs. 50%, respectively), although this difference was not statistically significant. 11 C-choline PET had a better detection rate for moderately differentiated HCC lesions but not for those poorly differentiated (75% vs. 25%, respectively). In contrast, 18 F-FDG PET exhibited the opposite behavior, with corresponding detection rates of 42% and 75%, respectively. The mean 11 C-choline SUV and T/L ratio in moderately differentiated HCC lesions were higher than those in poorly differentiated HCC lesions. In contrast, the mean 18 F-FDG SUV and T/L ratio in poorly differentiated HCC were higher than those in moderately differentiated HCC. These differences, however, were also not statistically significant. Conclusion: 11 C-choline PET had a better detection rate for moderately differentiated HCC lesions but not for poorly differentiated HCC lesions, whereas 18 F-FDG PET produced the opposite result. 11 C-choline is a potential tracer to complement 18 F-FDG in detection of HCC lesions.

Mesophase-pitch-based carbon fibers were heat-treated at high temperatures (2600 or 2800~ and examined as anodes for lithium secondary batteries. Four types of carbon fibers were used whose cross-sectional views are: a radial texture with wedge (type A), a radial texture with fine zigzag layers (type B), a double texture (type C), and a Concentric texture (type D). Lithium could net be deintercalated after the first lithium intercalation in the type A carbon fiber. The structure of the type A fiber was destroyed during lithium intercalation. The other three types of carbon fibers showed good rechargeability on the first cycle, but demonstrated different behavior after 30 cycles. The highest lithium intercalation and deintercalation capacity was observed for the radially oriented carbon fiber (type B). The x-ray results showed a reversible change in the lattice along the c-axis during the intercalation and deintercalatien cycle.

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