Scanning magnetic

Note Normally, three to ten m/z values are monitored 20-100 ms each in a cycle. Some settling time is needed for the mass analyzer after switching to the next value, e.g., 1-2 ms for pure electric scanning, 20-50 ms for a magnet scan. 

The magnetic scan is synchronised with the x-axis of a recorder and calibrated to appear as mass number (strictly m/e). The amplified current from the ion collector gives the relative abundance of ions on the y-axis. The signals are usually pre-processed by a computer that assigns a relative abundance of 100% to the strongest peak (base peak). 

Major elements were determined by magnetic scanning of the mass range of interest and recording the signals electrically. Calculations of the concentrations of the major elements were made using the following equation ... 

Figure 68. Sweep rate-dependent micro-SQUID magnetization scans collected for [(triphos) Re (CN)3]4[Mn Cl]4 at 0.5 K showing hysteretic behavior. The outermost curve corresponds to a scan rate of0.560 T/s, and the scan rate decreases for each successive curve by a factor of 2, reaching the value of 0.008 T/s for the innermost curve. [Adapted from (214)].

Mass spectroscopic runs were made on a CEC 21-103C spectrometer. GC/ MS runs were made on a DuPont 21-491 system composed of a PE 900 GC and a DuPont 21-491 magnetic scanning mass spectrometer. The samples were run on a 10-ft by 1/8-in. SE 30 column. 

Volume scanning remainder of measurements by magnet scanning. 

Fig. 17. Isotopic abundances of thallium recorded electrically by FDMS and signal accumulation in a multichannel analyzer. For each measurement SO cyclic magnetic scans are performed, a natural abundance of thallium, theor. m/z 203 = 29.5%, m/z 205 = 70.5% > found m/z 203 = 29.2%, m/z 205 = 70.S%, standard deviation 0.18, mean error = 0.08 b stable isotope-enriched internal standard, measurement certificate of the Russian manufacturer (supplied by RohstofTEinfuhr GmbH, Diisseldorf, FRG.) isotope T1 = 87.0%, isotope T1 = 13.0%, found m/z 203 = 87.7%, m/z 205 = 12.3%, standard deviation 0.46, mean error = 0.20 c quantitative determination of thallium traces in brain tissues. Found m/z 203 = 43.01 %, m/z 205 = 56.99%, standard deviation 1.28, mean error = 0.57...

Currently, there are no universally accepted tolerance values for the neck for the various injury modes. This is not due to a lack of data but rather to the many injury mechanisms and several levels of injury severity, ranging from life-threatening injuries to the spinal cord to minor soft-tissue injuries that cannot be identified on radiographic or magnetic scans. It is likely that a combined criterion of axial load and bending moment about one or more axes will be adopted as a future FMVSS. 

Figure 3.145 Zero-field-cooled (ZFC) and field-cooled (FC) magnetization scans for the 2 nm spherical iron nanopartides and the 2nmx11nm iron nanorods at the applied magnetic field of 100 Oe. Reproduced with permission from Ref. [82] 2000, American Chemical Society.

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