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TiAl alloy was electrochemically anodized in ethylene glycol electrolyte containing with NH4F to prepare anodic film. The influence of anodization treatment on the oxidation behavior and mechanical properties of the anodized TiAl alloy were then characterized. Results shown that based on the halogen effect a continuous and dense Al2O3 oxide scale will generate on the anodized TiAl alloy after high temperature oxidation. After oxidation at 1000 ℃ for 100 h, the weight gain of the anodized TiAl alloy was dramatically decreased from 85.86 mg/cm2 to 0.67 mg/cm2. Moreover, it is shown that the surface hardness and elastic modulus of the anodized TiAl alloy decreased first and then increased with the prolonging of oxidation time. Meanwhile, the friction coefficient of the anodized TiAl alloy increased comparing to the bare TiAl alloy. The surface wear resistance of the anodized TiAl alloy exhibited similar phenomena. This is because that during high temperature oxidation process, aluminum fluorides selectively transport to the surface through pores or micro-cracks, and are oxidized to Al2O3 at the surface region. The influence of anodization treatment on the mechanical properties of the anodized TiAl alloy is attributed to the Al2O3 content contained in the oxide scale.

The neutral salt spray test was carried out on TSZ410 stainless steel welded joints, and its corrosion behavior was studied using metallurgical microscope, scanning electron microscope, X-ray diffractometer, energy-dispersive spectrometer, electrochemical workstation, and weight-loss analysis. The results showed that after salt spray test for 128 days, there was obvious corrosion at the matrix while there was no visible corrosion at the weld seam and fusion area. The structure of the weld seam was not changed, indicating its good corrosion resistance. [ABSTRACT FROM AUTHOR]

Objective: To explore the clinical features and treatments of contact granuloma of larynx., Method: To find the best treatments by analyzing the clinical features, related causes and the treatments of the 13 contact granuloma of larynx cases, which have complete data, of our department from Jan 2005 to Dec 2012, also by comparing the effect of conservative treatment and operation treatment., Result: Contact granuloma of larynx is more common in men (84.6%). The main causes are gastro esophageal reflux, chronic cough, habitual hawk and endotracheal intubation disease. However, a big part (38.4%) gets the disease without any other disease history. The main clinical feature of the disease includes: sensation of foreign matter in throat, easy to get exhausted when talking and voice hoarse, but also 30.7% without any feature in throat. Among the 13 cases, 6 were treated by operation and the first recurrence was 66.6%. The cure rate was 50% after one or two operations. The other 7 were treated in conservative way, including anti- Gastro esophageal reflux, avoiding excessive talking, reducing habitual hawk ,or without any medical treatment. The cure rate was 57.1%. The total cure rate was 53.8%. However, it is nonsense to comparing the two different treatments (Chi2 = 0.066, P > 0.05)., Conclusion: There is still no standard treatment for contact granuloma of larynx and the effect is not good enough. The treatment should be depending on individual case. Conservative treatment is the first choice. However, operation should be considered if the patient has obviously hoarse and his granuloma is too large to breathe well.

Objective: To analyze the clinical features of scoliosis associated with Chiari I malformation in adolescent patients, and to explore the validity and safety of one-stage posterior approach and vertebral column resection for the correction of severe scoliosis., Methods: Between October 2004 and August 2008, 17 adolescent patients with scoliosis associated with Chiari I malformation were treated with surgical correction through posterior approach and pedicle instrumentation. There were 9 males and 8 females with an average age of 15.1 years (range, 12-19 years). The MRI scanning showed that 16 of 17 patients had syringomyelia in cervical or thoracic spinal cord. Apex vertebra of scoliosis were located at T7-12. One-stage posterior vertebral column resection and instrumental correction were performed on 9 patients whose Cobb angle of scoliosis or kyphosis was more than 90 degrees, or who was associated with apparent neurological deficits (total spondylectomy group). Other 8 patients underwent posterior instrumental correction alone (simple correction group). All patients' fixation and fusion segment ranged from upper thoracic spine to lumbar spine., Results: The operative time and the blood loss were (384 +/- 65) minutes and (4 160 +/- 336) mL in total spondylectomy group, and were (246 +/- 47) minutes and (1 450 +/- 213) mL in simple correction group; showing significant differences (P < 0.05). In total spondylectomy group, coagulation disorder occurred in 1 case, pleural perforation in 4 cases, and lung infection in 1 case. In simple correction group, pleural perforation occurred in 1 case. These patients were improved after symptomatic treatment. All patients were followed up 24-36 months (32.5 months on average). Bony healing was achieved at 6-12 months in total spondylectomy group. No breakage or pulling-out of internal fixator occurred. The angles of kyphosis and scoliosis were significantly improved at 1 week after operation (P < 0.01) when compared with those before operation. The correction rates of scoliosis and kyphosis (63.4% +/- 4.6% and 72.1% +/- 5.8%) in total spondylectomy group were better than those (69.4% +/- 17.6% and 48.8% +/- 19.3%) in simple correction group., Conclusion: Suboccipital decompression before spine deformity correction may not always be necessary in adolescent scoliosis patients associated with Chiari I malformation. In patients with severe and rigid curve or apparente neurological deficits, posterior vertebral column resection would provide the opportunity of satisfied deformity correction and decrease the risk of neurological injury connected with surgical correction.