What energies are the peaks at spect?
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The peaks at SPECT have different energies depending on the specific study. In the case of Marcassa and Zoccarato, they discuss the use of two different isotopes, Tl201 and 99mTc-labeled tracers, with Tl201 injected at rest and 99mTc-perfusion tracers injected at peak stress. They mention the downscatter effect, where higher energy photons contaminate the lower energy window, potentially degrading the image quality . Lewis, Merkel, and Hamill measured low-energy electron-reflection (LEER) spectra for various molecules and observed peaks at different energies, including 3.1 and 4.6 eV for 1-hexene and 3.0 and 4.7 eV for cyclohexene . Harris, Reid, Ballantine, and Parry measured the double-ionization energies of N2O2+ using double-charge-transfer spectroscopy and found peaks at energies such as 35.7 ± 0.4 eV . Otto investigated peak profiles of standard reference materials using energy-dispersive X-ray diffraction and found that the profiles were essentially pure Gaussians independent of energy . Prasanna, Reddy, and Krishnamoorthy studied the energies of excitation source, spectral peaks, and modulation spectrum in speech production and found changes at the vowel onset point (VOP) .
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17 Citations | The peaks in the spectrum correspond to double-ionization energies of 35.7 ± 0.4, 38.8 ± 0.4, 41.8 ± 0.4, and 43.1 ± 0.4 eV. |
| The energy peaks in SPECT imaging vary depending on the isotopes used, such as 140 keV for I-123 and 159 keV for Tc-99m. | |
30 Citations | The energy of the peaks in the spectra is not mentioned in the provided information. |
16 Citations | The peaks in the spectra are at approximately 3.1 and 4.6 eV for 1-hexene, and at 3.0 and 4.7 eV for cyclohexene. |
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