【多选题】下列有关粉尘爆炸的特性及影响因素中正确的有( )。
A.
评价粉尘爆炸危险性的主要特征参数是爆炸极限、最小点火能量,最低着火温度、粉尘爆炸压力及压力上升速率
B.
粉尘爆炸极限不是固定不变的,它的影响因素主要有粉尘粒度、分散度、温度、点火源的性质、可燃气含量、氧含量、惰性粉尘和灰分温度等
C.
一般来说,粉尘粒度越细,分散度越低,可燃气体和氧的含量越小,火源强度、初始温度越低,湿度越高,惰性粉尘及灰分越少,爆炸极限范围越大,粉尘爆炸危险性也就越大
D.
粉尘爆炸压力及压力上升速率主要受粉尘粒度、初始压力、粉尘爆炸容器、湍流度等因素的影响。粉尘爆炸压力对粉尘爆炸压力上升速率的影响比粒度对它的影响大
E.
当粉尘粒度越细,比表面越大,反应速度越快,爆炸上升速率就越大。随初始压力的增大,对密闭容器的粉尘爆炸压力及压力上升速率也增大,当初始压力低于压力极限时,粉尘则不再可能发生爆炸
【简答题】2017卷的阅读理解 When you are in England , you must be very careful in the street because the traffic drives on the left. You must look at the right first and then the left, then you can cross the street. I...
【多选题】以下有关爆炸极限范围说法正确的是( )。
【简答题】根据短文内容,判断正(T)误(F)。 When you are in Hong Kong, you must be very careful in the streets, because the traffic drives on the left. It is different from that in other areas of China. If this is the first t...
【单选题】一般来说,粉尘粒度越细,分散度越高,可燃气体和氧的含量越大,火源强度、初始温度越高,湿度越低,惰性粉尘及灰分( ),爆炸极限范围( ),粉尘爆炸危险性也就越大。正确答案为( )。
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