Manipulating Oxidation of Silicon with Fresh Surface Enabling Stable Battery Anode.

Silicon (Si)-based material is a promising anode material for next-generation lithium-ion batteries (LIBs). Herein, we report the fabrication of a silicon oxide-carbon (SiOx/C) nanocomposite through the reaction between silicon particles with fresh surface and H2O in a mild hydrothermal condition, as well as conducting carbon coating synchronously. We found that controllable oxidation could be realized for Si particles to produce uniform SiOx after the removal of the native passivation layer. The uniform oxidation and conductive coating offered the as-fabricated SiOx/C composite good stability at both particle and electrode level over electrochemical cycling. The as-fabricated SiOx/C composite delivered a high reversible capacity of 1133 mAh g-1 at 0.5 A g-1 with 89.1% capacity retention after 200 cycles. With 15 wt % SiOx/C composite, graphite-SiOx/C hybrid electrode displayed a high reversible specific capacity of 496 mAh g-1 and stable electrochemical cycling with a capacity retention of 90.1% for 100 cycles.

[Clinical observation of imaging expression and operation treatment for intramedullary schwannoma of thoracolumbar spine].

OBJECTIVE: To explore the imaging characteristics and operation outcomes of intramedullary schwannoma in thoracolumbar spine. METHODS: From June 2005 to December 2012,17 patients with intramedullary schwannoma in thoracolumbar spine were operated through posterior approach, including 11 males and 6 females with an average age of 53 years old ranging from 46 to 67 years old. The courses of disease ranged from 3 to 5 years (averaged 3.3 years). Thoracic patients manifested chest and back pain,numbness and inability on lower limb gradually, unsteady gait. Lumbar patients manifested low back pain,radiating pain and numbness on lower limb, intermittent claudication. Preoperative VAS score was 5 to 8 with an average of 6.12. Eleven patients suffered from never injury, 4 cases were grade C, 5 cases were grade D and 2 cases were grade E according to Frankel classification. Three patients were injured on thoracic segments, 5 patients were on thoracolumbar segments, 3 patients on lumbar segments and 6 patients on lumbosacral segment confirmed by CT and MRI. Five patients were epidural, 12 were intradural extramedullary. Six patients underwent spinal decompression and tumor resection simply, eleven patients underwent spinal decompression, tumor resection, internal fixation and bone graft fusion. RESULTS: No injury of blood vessel or spinal cord occurred during operation, cutting healed well. All patients were followed up from 12 to 60 months with an average of 32 months. Chest and back pain, low back pain, radiating pain and numbness on lower limb were improved significantly. VAS score at final follow-up was 0 to 3 (averaged 1.5). According to Frankel classification, 5 cases were grade D, and 6 cases were grade E at final follow-up. CONCLUSION: MRI is an effective method in diagnosis of intramedullary schwannoma in thoracolumbar spine. Operative method is choosed by imaging expression, and the aim is effectively decompression of spine, reconstruction of stability of spine.