下面关于后印象主义的特点描述不正确的一项是?() ["A、表达自我","B、表达主观","C、自然主义","D、表达人的内心情感"]
两块厚度相同的钢板的对接接头,材料为Q235A钢。已知焊缝长度为80mm,板厚为10mm,Q235A钢的焊缝许用拉应力[σt′]为167MPa,求该焊缝能承受多大拉力?
下面哪一位不是印象派画家的代表?() ["A、勃朗特","B、雷诺阿","C、莫奈","D、德加"]
下面哪一位是点彩派画家的代表?() ["A、库尔贝","B、荷尔拜因","C、丢勒","D、席妮科"]
表观吸收水分组成浓度n/w,反映了植物()之间的关 ["A、吸水与吸肥","B、吸水与开花","C、吸肥与开花","D、吸水与生长"]
已知12Cr1MoV钢中,ω(C)=0.15%、ω(Mn)=0.6%、ω(Cr)=1.2%、ω(Mo)=0.3%、ω(V)=0.3%,求该种钢的碳当量。