球铁中注管耐火砖成型模内衬的选材研制

分析了10钢制中注管耐火砖成型模具内衬的失效形式及原因。论证了采用稀土镁球铁代替10钢制作模具内衬的可行性。生产试验表明,稀土镁球铁内衬的使用寿命是10钢的16倍,且可降低成本,节约能源。     

Institutional experience of PTH evaluation on fine-needle washing after aspiration biopsy to locate hyperfunctioning parathyroid tissue

Assaying parathyroid hormone (PTH) in the washing liquid after fine-needle aspiration biopsy (FNAB) seems to be a valid approach to locate parathyroid tissue. PTH-FNAB was evaluated in 47 patients with a clinical picture of primary hyper-parathyroidism (PHP) and ultrasonography (US) suggestive of parathyroid lesion. The patients were subdivided into two groups on the basis of the absence or presence of US thyroid alterations. The result of PTH-FNAB was compared with those of cytology, scintigraphy and, in 24 patients, surgical outcome. PTH-FNAB samples with a value higher than that recorded in the serum and higher than our institutional cut-off were deemed to be probable samples of parathyroid tissue. Cytology proved diagnostic for benign thyroid lesions, non-diagnostic for thyroid lesions, hyperplastic parathyroid tissue, undetermined or malignant thyroid lesions and other lesions in 45%, 30%, 17%, 4%, and 4% of cases, respectively. In 47% of cases, PTH-FNAB indicated that the sample had been taken in parathyroid tissue. In patients without US alterations, the diagnostic accuracy of PTH-FNAB was greater than that of scintigraphy. After surgery, comparison between the results of PTH-FNAB and scintigraphy, in terms of positive predictive value (PPV), revealed the superiority of PTH-FNAB; PPV was 94% for FNAB and 71% for scintigraphy, while sen-sitivity was 83% and 69%, respectively. PTH-FNAB evaluation after FNAB appears to be more diagnostic than cytology and scintigraphy. Of all the procedures used, PTH-FNAB appears to be the method of choice when the target is US suggestive and reachable. PTH-FNAB appears to be a useful method of guiding surgical intervention.     

漏斗砖成型模内衬选材研究

本文对漏斗砖成型模内衬的选材进行了详细的分析，生产试验表明，采用稀土镁球墨铸铁代替ZG45铸钢制作漏斗砖成型模内衬是完全可行的，其使用寿命可提高50％左右，且成本大为降低。     

球墨铸铁石墨开花问题的分析与防范

减少原料中碳的遗传、避免球化处理时出现大的石墨球、降低高温铁水的热混流、降低碳的活度和增强奥氏体的强度、准确把握球化处理和倒包时铁水量、准确控制出炉温度和浇注温度是防止石墨开花的有效途径。