轴径磨损量小于()mm,而轴径表面又要求一定硬度时,可采用镀铬的方法进行修复。
A.0.05
B.0.1
C.0.2
D.0.5
A.0.05
B.0.1
C.0.2
D.0.5
(重庆大学2007年考研试题)圆管流动过流断面上切应力为()。
A.管轴处为零,且管壁处为最大
B.沿径向不变
C.管壁处为零,且管轴处为最大
D.管轴处为零,管壁处也为零
A.弥漫性结节性甲状腺肿
B.甲状腺非典型腺瘤
C.甲状腺髓样癌
D.甲状腺乳头状腺癌
E.甲状腺滤泡性腺癌
根据气力输送的特点,降低动力消耗,节约能源是一个重要的研究课题,从经验中知,管道内径是关于能耗的重要参数。直观上看,当输送量一定时,管径过小,输送易阻滞,管径过大,虽输送畅通,但又造成能量的浪费。根据经验,把管径分成三组,各组的试验结果如下表所示,试用方差分析法比较各组的效果.
管径(mm) | 单位功耗 |
230 | 0.0308,0.0476,0.0504 |
250~260 | 0.0532,0.032,0.0218,0.028,0.028, 0.042,0.0336,0.042,0.042,0.028 |
280~320 | 0.07,0.07,0.0644,0.0312,0.0756,0.0756, 0.07,0.0588,0.0588,0.042,0.0308,0.0364, 0.0448,0.21,0.154,0.1064,0.1288,0.112, 0.1064,0.1288,0.0756,0.0644,0.0504,0.0644, 0.0504,0.0308 |
由于眼球前后径过长而导致眼的折光能力异常称为()
A. 近视
B. 远视
C. 散光
D. 老视
E. 正视
A.偏执型人格障碍
B.强迫型人格障碍
C.分裂型人格障碍
D.反社会型人格障碍
A.μN=0.64<0.85,符合规程要求
B.μN=0.82<0.90,符合规程要求
C.μN=0.69<0.90,符合规程要求
D.μN=0.78<0.85,符合规程要求
A.有明显腐蚀和冲刷减薄的弯头、三通、管径突变部位,不包括相邻直管部位
B.需重点管理的管道,其他没有要求
C.需重点管理的管道,其他管道的弯头、三通、管径突变部位及相邻直管部位
D.需重点管理的管道或有明显腐蚀和冲刷减薄的弯头、三通、管径突变部位及相邻直管部位