Electron direct injection

If electrons are injected not exactly along the equipotential surface, but with an angular spread Aa about the correct direction, then the energy resolution is given by ... 

Flame (direct injection) Thermo-electron IL 157 single channel IL 357 single beam IL 457 single channel double beam Video 11 single channel single beam Video 12 single channel double beam Video 22 two double channels... 

Analytical Procedures. Incubation mixtures were extracted with diethyl ether except in the case of toxaphene where a mixture of chloroform-methanol (5 1, v/v) was used instead. Ether extracts of DDT, dieldrin, and lindane were dried over anhydrous sodium sulfate, evaporated using a gentle stream of nitrogen, and the residues were redissolved in n-hexane. Aliquots of the hexane solutions were directly injected into a gas liquid chromatograph (GLC, Varian, model 240 ) equipped with an electron capture (EC) detector (Aerograph Sc H detector) and a 1.5% 0V-101 on chrom GHP 100/120, 5 x 1/8" stainless steel column. The detector temperature was 245°C, injection port 235°C, and the oven temperature was 125°C for lindane, 180°C for DDT and 200°C for dieldrin. Carrier gas was nitrogen at the flow rate of 40 ml/min. 

Fig. 5.17 Demonstration of MS-based bioassay functionality using a plant extract. MS instrument Ion-trap mass spectrometer (LCQ Deca, Thermo Electron), (a) MS analysis of pure extract by direct injection onto restricted-access column 2 in the absence of affinity protein, (b) Analysis of the same natural extract spiked with digoxin using the label-free MS assay method as shown in Fig. 5.15.

Hydrazine may be derivatized with salicylaldehyde to a hydrazone derivative, separated on a suitable HPLC column and determined by a UV detector. Aqueous samples may be directly injected into a polar GC column interfaced to an FID. Anhydrous hydrazine may be appropriately diluted in alcohol or ether and determined by GC/MS. The molecular ion for GC/MS determination by electron-impact ionization is 32. 

When an electron is injected into a polar solvent such as water or alcohols, the electron is solvated and forms so-called the solvated electron. This solvated electron is considered the most basic anionic species in solutions and it has been extensively studied by variety of experimental and theoretical methods. Especially, the solvated electron in water (the hydrated electron) has been attracting much interest in wide fields because of its fundamental importance. It is well-known that the solvated electron in water exhibits a very broad absorption band peaked around 720 nm. This broad absorption is mainly attributed to the s- p transition of the electron in a solvent cavity. Recently, we measured picosecond time-resolved Raman scattering from water under the resonance condition with the s- p transition of the solvated electron, and found that strong transient Raman bands appeared in accordance with the generation of the solvated electron [1]. It was concluded that the observed transient Raman scattering was due to the water molecules that directly interact with the electron in the first solvation shell. Similar results were also obtained by a nanosecond Raman study [2]. This finding implies that we are now able to study the solvated electron by using vibrational spectroscopy. In this paper, we describe new information about the ultrafast dynamics of the solvated electron in water, which are obtained by time-resolved resonance Raman spectroscopy. 

Photocurrent voltage curves have been studied with molybdenum selenide crystals of different orientation and different pretreatment. Figure 5 represents results for three typical surfaces of n-type MoSe (JJ+). An electrode with a very smooth surface cleaved parallel to the van der Waals-plane shows a very low dark current in contact with the KI containing electrolyte since iodide cannot directly inject electrons into the conduction band and can only be oxidized by holes. At a bias positive from the flat band potential U where a depletion layer is formed a photocurrent can be observed as shown in this Figure. This photocurrent reaches a saturation at a potential about 300 mV more positive than when surface recombination becomes negligible. 

A final topic to be discussed in this section is the direct injection of electrons into a liquid by the use of nanowires. The difference with the discharge processes described above for the point electrodes is twofold the use of nanostructured electrodes and the generation of solvated electrons, instead of the initiation of a discharge. Solvated electrons have a very short... 

Nicolson and Meresz [515] directly injected the drinking water sample into a gas chromatograph equipped with a scandium tritide electron capture detector. Glass columns (1.2mmx6mm) packed with Chromosorb 101 (60-80 mesh) were used for the analysis. The conditions for operating the instruments were as follows. 

Figure 4.3 Arrangement of HPLC equipment for termination of reaction by direct injection of sample. A sample is removed from the reaction mixture and transferred directly to the injection port for introduction onto the column. The HPLC column is protected by a guard column, which removes debris. The eluent flows through the detector, from which a signal is displayed on a recorder. The area of each peak is electronically integrated.

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