【判断题】【消耗次数:1】
气相色谱柱温选择原则是:在最难分离的组分有好的分离度、不拖尾且保留时间适宜的前提下,尽可能采取较低柱温。
正确
错误
参考答案:
复制
纠错
相关题目
【判断题】 气相色谱仪器检测室温度需低于柱温,至少等于柱温。
①  正确
②  错误
【单选题】 在满足(  )的前提下应该尽可能的选择季相性明显的植物。
①  植物光照需要
②  植物生态习性
③  植物水分需求
④  植物生理习性
【多选题】 色谱柱在使用一段时间后出现柱效下降(分离能力降低、色谱峰扩张变形),可能的原因是
①  色谱柱进样端固定液流失
②  色谱柱内固定液分布不均匀
③  色谱柱内固定液性能改变
④  流失的固定液污染了检测器
【判断题】 两组分保留时间之差越大且色谱峰越窄,分离效果越好。
①  正确
②  错误
【判断题】 气相色谱法的优点是分离效能高,选择性好
①  正确
②  错误
【单选题】 气相色谱分析影响组分之间分离程度的最大因素是
①  进样量
②  柱温
③  载体粒度
④  气化室温度
【判断题】 气相色谱法分离非极性物质,一般选用非极性固定液。试样中各组分按沸点从高到低的顺序流出色谱柱。
①  正确
②  错误
【判断题】 为保证空心阴极灯的寿命,在满足分析灵敏度的前提下,灯电流应尽可能的小。
①  正确
②  错误
【单选题】 在气相色谱中,直接表征组分在固定相中停留时间长短的保留参数是
①  保留时间
②  调整保留时间
③  死时间
④  相对保留值
【单选题】 以硅胶为吸附剂的柱色谱,分离极性较弱的物质时宜选用的流动相是
①  极性较强的流动相
②  活性较高的吸附剂和极性较弱的流动相
③  活性较低的吸附剂和极性较弱的流动相
④  活性较高的吸附剂和极性较高的流动相
随机题目
【单选题】 I’m very sorry to kept you ______ for two hours.
①  wait
②  waited
③  waits
④  waiting
【单选题】 If you listen to the tape again and again, you may ____.
①  want to retell the general meaning of what you hear from the tape
②  feel so bored that you cannot understand what you hear from the tape
③  understand what you hear from the tape better and better
④  repeat the exact words you hear from the tape
【单选题】 Some handicapped people may be ______ to go out at all and a visitor is more than welcome.
①  able
②  unable
③  disable
④  disabled
【单选题】 I was ______ tired that I had to rest.
①  very
②  so
③  enough
④  too
【单选题】 In the eyes of the author, one should start from ______ in wide reading.
①  interesting materials
②  books with very few pages
③  materials not too difficult
④  both A and C
【单选题】 In the first sentence, “by no means” means ____.
①  without method
②  not at all
③  absolutely
④  above all
【单选题】 You’ll be late, ______ you start at once.
①  or
②  if
③  and
④  unless
【单选题】 The article ______ in French were impossible for me to read.
①  written
②  writing
③  write
④  wrote
【单选题】 Is this ______ looking for?
①  you are
②  that you are
③  what you are
④  what are you
【单选题】 According to the author, in order to have a good command of English one must ____.
①  employ as many learning strategies as possible
②  expect to gain an easier task
③  exert oneself constantly
④  sustain oneself