Mechanical and Acoustic Performance Test of New Designed Metal Noise Barrier Unit Plate with No Riveted Connection

The modern transportation system is increasingly developed during recent years.It is an effective solution to set the noise barriers to reduce the traffic noise pollution caused by different kinds of transportation systems.Many deficiencies on concrete noise barriers and metal noise barriers with rivet structure can be eliminated by a new kind of noise barrier with no-riveted structure.The mechanical performance examination and acoustic performance test are conducted on the new-designed noise barrier with no-riveted structure.The results indicate that the maximum stress is 1.74 MPa and the maximum deformation is 1.04 mm with load acting on the unit plate.The noise reduction coefficient of this kind of no-riveted noise barrier unit plate is 0.75 and its noise insulation is 40 dB,which were conform to or superior to the standard requirements.Therefore,this new designed noise barrier meets the field application requirements of mechanical and acoustic performance,which demonstrates the noise barriers can be widely promoted.

曝光2A3B、2A3C电子管

曙光生产的2A3为双管并联型，因音色优美，有小“300B”之称。2004年5月曙光首先推出了2A3B，采用了单屏设计，灯丝采用了高强度的弹簧钩结构，克服了原2A3的灯丝由于热膨胀可能造成的松动，从而使输出不稳定。新的2A3B绝无此状况，且输出功率也有所增加，并且上下云母片都采取了防漏电设计，极大地解决了2A3形成的漏电噪音。其稳定性很好，已经超过俄罗斯同类管。