【简答题】某反应在催化剂存在时,反应的活化能降低了41.840kJ/mol,反应温度为625K时,测得有催化剂存在时的反应速率常数为无催化剂时的1000倍,结合催化作用的基本特征说明该反应中催化剂是怎样使反应速率常数增加的。
【单选题】下列选项中,属于人工被动免疫的生物制品是:
【单选题】In a listening activity, students are asked to note down the time and places of events. The aim of this activity is to develop the skill of__________.
B.
listening for specific information
C.
listening for structure
D.
listening for vocabulary
【判断题】催化剂的使用,降低了反应活化能,使活化分子总数增加,反应加快。
【判断题】随着电子商务的发展对通信技术的要求也不断提高,但目前还没有涉及无线移动通信技术。
【简答题】Scientists in Israel have discovered a new way to test for water pollution by “listening” to what the plants growing in water have to say. By shining a laser beam (激光束) on the tiny pieces of algae flo...
【单选题】Rugby has the reputation of being the roughest sports in the world. Outside the British Isles, rugby is little known and, in fact, is often confused with soccer. But in England, as old sports saying s...
A.
compare English and American sports
B.
compare rugby to football
C.
discuss the brutality of rugby
D.
provide a brief introduction to rugby
【判断题】消费者个性的可塑性决定消费者需求的可诱导性