直接支配小汗腺活动的神经纤维是A．肾上腺素能纤维 B．胆碱能纤维 C．肽能纤维 D． 发布时间：2018-06-17 17:49 │ 来源：www.tikuol.com 题型：单项选择题 问题： 直接支配小汗腺活动的神经纤维是A．肾上腺素能纤维B．胆碱能纤维C．肽能纤维D．副交感神经节后纤维E．交感神经节前纤维
题型：单项选择题 完形填空。 A coal mine gas explosion (瓦斯爆炸) yesterday morning in Tongchuan, Shanxi Province in Northwest China, killed five miners (矿工) and left 1 missing. The explosion took place in the Chenjiashan Coal Mine in Tongchuan at about 7:10 a.m. yesterday, 2 293 miners were working underground. People above ground saw thick smoke 3 out of a mine at about 7:30 when communication underground was 4 . Shortly after the accident, President Hu Jintao gave instructions urging (督促) the local government and departments 5 their best to save the 6 miners. It was about 8000 metres from 7 the workplace where the explosion took place. It was very difficultto save those trapped miners. By 5:00 p.m. on Sunday, 127 out of the 293 workers working there when theexplosion took place were brought up. Five were dead, and another 166 8 . An officer said 9 there is no air in the underground area where the missing miners are, it is 10 for them to have survived. ( ) 1. A. 166 others ( ) 2. A. after ( ) 3. A. comes ( ) 4. A. got off ( ) 5. A. tried ( ) 6. A. trapping ( ) 7. A. the entrance of( ) 8. A. were missed ( ) 9. A. since ( ) 10. A. possible B. another 166 B. before B. was coming B. put off B. to try B. were trapping B. the entrance toB. missing B. while B. impossible C. 166 the otherC. when C. coming C. cut off C. to try to C. trapped C. the way to C. were missing C. because of C. unpossible D. the other 166 D. since D. came D. taken off D. tried to D. were trapped D. the way of D. to miss D. as D. possiblely 查看答案
题型：单项选择题 （6分）已知某烃A含碳元素的质量分数为85.7％。结合以下信息回答问题：(1)若烃A密度是相同状况下氢气密度的42倍。则烃A的相对分子质量_____________，分子式为_____________。(2) 若烃A可作果实催熟剂。则由A制取高分子化合物的化学方程式为 A和水在一定条件下反应生成B。B为生活中常见的有机物，B可与另一种生活中常见有机物在一定条件下反应生成有香味的物质C，写出生成C的化学方程式 查看答案