Inert gas flow

Additional samples were prepared from the three resins and were heated at temperatures between 940° and 1100°, under different inert gas flow rate and with different heating rates. The samples have different microporosities and show different capacities for lithium insertion. The results for all the carbons prepared from resins are shown in Fig. 32, which shows the reversible capacity plotted as a function of R. The reversible capacity for Li insertion increases as R decreases. This result is consistent with the result reported in reference 12,... 

The reagents ratio, reaction temperature, reaction time and inert gas flow have been reported as the variables of KOH activation process, which influence effectively the porosity development on the treatment of a given carbonaceous material with potassium hydroxide [6],... 

Before injection of 0.5-lml of solution into the zinc column, the inert gas flow rate was adjusted to 0.71 min-1, and the furnace (1700°C) and recorder were turned on and allowed to establish a stable baseline (approximately 10s). The solution was injected as quickly as possible using a syringe and the furnace turned off when the recorder signal had returned to the previously established baseline (approximately 20s). 

SSP can be carried out batchwise or continuously, either in vacuo or supported by an inert gas flow. Another variation of SSP is the so-called suspension process in the swollen state, which allows for the production of extremely high-molecular-weight polyesters [3], This technology is more of academic interest than for commercial application since it requires complete removal of the high-boiling suspending oils. 

Newly packed traps should be conditioned overnight at 230°C with an inert gas flow of at least 20 ml/min. The trap is also conditioned prior to daily use by backflush-ing at 180°C for 10 min. 

As sweep gas flow rate is increased, the performance of the reactor improves until the flow rate is about one thousand times the reactant flow rate. The concentration of all species, but most importantly formaldehyde decreases in the shell side of the reactor as this happens. This increases the driving force for permeation of all species. After increasing this flow rate to a certain point further increases in inert gas flow rate do not change the concentration gradient of any species along the reactor because the shell concentrations of all species is... 

Experiment B. Place an accurately weighed 150-200 mg sample of powdered YBa2Cus07 x in the titration beaker and begin inert gas flow. Add 10 mL of 1.0 M HC104 and 0.7 M KI and stir magnetically for 1 min. Add 10 mL of water and complete the titration. 

Plasma Discharge. The low-voltage and high-current-density process in plasma gas is often called arc plasma or hot plasma. A high-power ion beam formed in the plasma flame hits the target substances to heat them to several thousand kelvins, which is enough to melt all solid materials. Under the inert gas flow, the vaporized... 

The reducibility of nickel and copper cations in Nb- and Al-containing MCM-41 It is known that transition metal cations, which occupy extra lattice positions in zeolites, are reduced while activated under vacuum or in an inert gas flow [20], The same occurs while applying mesoporous matrices for metal cations. The species formed during the auto reduction depend on the nature of a matrix, the conditions of cation modification, and activation They can be identified by H2-TPR, ESR, and NO/FTIR measurements. 

Fig. 1.2. Manifold for medium vacuum and inert gas. A low-temperature trap, on the right side of the figure, is used in the vacuum line to protect the pump from harmful vapors. When the apparatus is being filled with gas or purged with inert gas, the valve on the pressure release bubbler (which contains a check valve to prevent oil from backing up into the line) is opened to avoid excess pressure which would blow the apparatus apart. Often a mineral oil bubbler (not shown here) is connected in line with the inert-gas source to provide visual indication of the inert-gas flow.

Fig. 1.24. Opening a sealed ampule. (a) The neck of the ampule is carefully scored using a glass knife. (b) A metal tube of larger diameter than the ampule neck is placed over the neck. Inert gas flowing through the metal tube will minimize exposure of the ampule contents to air once the neck is broken. A quick jerk is then applied to the metal tube, which snaps the neck off (c) at the score.

Fig. 8.9. Notched stopcock plug. A triangular file drawn across the orifice at right angles to the length of the plug will notch the orifice. This may then be used to better control gas flow, such as an inert-gas flow while working on a Schlenk manifold.

Fig. 4.1. Apparatus for purging solvents with inert gas. (n) A long needle attached to an inert-gas source is directed through the sidearm and into the solvent. A slow inert-gas flow runs through the sidearm to avoid back-diffusion of air into the flask. (b) Solvent purge using a septum and a doubleneedle arrangement.

An Electron Capture Detector operates as follows a CECD is essentially a tube thru which a stream of inert gas flows. A weak radioactive source on the walls of the tube irradiates the gas and generates within it a population of free electrons. These electrons are extracted from the gas stream by a positive electrode. The number extracted per second is measured as a current flowing thru this electrode... 

When the inert gas flow rate is increased, the gas-solid contact regime evolves from the conventional spouted bed... 

Formation of metal clusters by gas aggregation, in which metal atoms are evaporated or sputtered into a cooled inert gas flow at relatively high pressure, has been well established in last decade. By repeated collisions with the carrier gas, the supersaturated metal vapor nucleates and forms clusters. The mechanism of cluster formation can be explained with homogeneous and heterogeneous nucleation theories. The gas aggregation methods have been applied extensively to produce small clusters of metals such as zinc, copper, silver etc. [23-26]. In some cases this method was used in combination with a mass filter such as a quadruple or a time-of-flight spectrometer [27, 28], The metal vapor for cluster source can be produced by either thermal evaporation [23-28] or sputter discharge [22, 29]. 

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