怪侠一把刀
第68楼2007/07/25
新问题之二:After replacing column for SIM analysis why are no peaks identified? 更换柱子之后,SIM模式下扫描检测不到任何组分?
解答:SIM analysis typically performs grouping and changes the ions captured in each time band. Changing the column usually causes the peak retention times to change. If the retention time for a particular compound's peak changes the peak will not appear if the ions required to capture that compound's peak are not set. In this situation, perform another scan measurement, reconfigure the SIM data acquisition conditions based on this data, and then perform the SIM measurement. You can also obtain the data by performing synchronous SIM/Scan data acquisition.
jhzhang33
第72楼2007/12/27
• 为何谱库检索结果不只一次报告同一化合物?
The NIST, WILEY, and other libraries were not produced by Agilent.NIST, WILEY,以及其它谱库不是由Agilent创建的。他们包含由磁质谱和不同厂家MS产生的谱图。因为谱库包含同一化合物的多次扫描结果,化合物可能在结果中多次显示。在延扩展的数据分析页面,打开[光谱]菜单并点击[编辑搜索策略]以打开[搜索策略]对话框。选择[删除重复的CAS 号]检验栏即可解决同一化合物出现多次的问题。
jhzhang33
第74楼2007/12/27
新问题之二:更换色谱柱后做SIM扫描无可确定的峰?解答:SIM扫描通常用于分组分析和改变各时间段的扫描离子。柱子改变通常导致峰保留时间的改变。如果某一特定化合物峰的保留时间改变了,因为该化合物的特征离子在该时间段未设置,这将导致该化合物峰不出现。在这种情况下,应再进行一次全扫描,以重置SIM的扫描特征离子以进行SIM检测。你也可通过同时进行SIM/Scan 来获得这些数据。
怪侠一把刀
第81楼2008/01/11
What is QuickSwap and how does it works?
QuickSwap is a T-connection placed between the end of the gc column and the entrance to the MSD transfer line. A purge gas flow mixes with column effluent, passes into a deactivated fused silica restrictor inside the transfer line, and then into the MSD source. QuickSwap provides:
• A means for removing or changing columns without the need to cool and vent the MSD.
• Protection from entrance of air when doing routine maintenance on columns and inlets.
• A means for backflushing columns to remove high-boiling components, reducing run times and cool-down times and minimizing ghosting (chemical noise in the baseline) from run to run.
Attached Document describes workings of quickswap.
QuickSwap快速切换装置如何工作
s219
第86楼2008/01/23
灵敏度测试的方法是?我还没有用过