Preheat method

Hamatani Archival thyroid High Pure RNA Breakpoint cluster Preheating method... 

It was observed that higher temperatures were reached in the reactor on changing the preheating method, the effect being more pronounced at 02 CH4 feed ratios lower than 0.7, due to the minor extent of the oxidation reaction. However, the trend of the temperature profile along the reactor was unchanged irrespective of the means of reactant preheating. 

Table 9.1 Reactor temperature profiles as a function of preheating method.

Preheating method T comb (°C) TrefL (°C) TrefM (°C) TrefH (°C)... 

Figure 9.11 H2 outlet concentration and overall CH4 conversion in different preheating methods.

The steps in the ASE process are shown in Figure 3.8. The sample is loaded into the extraction cell, and then the solvent is pumped in. Then the cell is heated to the desired temperature and pressure. The heat-up time can be 5 to 9 minutes (for up to 200° C). This is referred to as the prefill method. Alternatively, the sample can be heated before adding the solvent, which is known as the preheat method. However, the preheat method is prone to the loss of volatile analytes. Therefore, the prefill approach is generally preferred [46],... 

Preheating methods are convection, infrared, radio frequency, and steam. Thermostatically controlled gas or electrically heated ovens are inexpensive methods of heating. The quickest, and possibly the most efficient, method is radio-frequency heating, but it is also the most expensive. Preheaters are located adjacent to the molding press and are manually operated for each cycle. 

Table 5.12 Comparison of different siurry preheating methods and their influence on selected parameters.

Table 2.1 Advantages and disadvantages of preheating methods (Based on [10-12])...

Some limestones, more often the coarse crystalline types, can never be calcined successfully. Such stone tends to decrepitate during preheating or calcination into fine particles that interfere with this pyrochemical reaction. The adaptabiflty of a stone for calcination can only be ascertained with surety by empirical methods. Possibly the greatest influence on lime quaflty is the size gradation of limestone. Narrow gradations, such as... 

Alcohol Amination. There are many similarities in the process technologies for Methods 1 and 2. In both, an alcohol reacts with ammonia over a fixed catalyst bed at elevated temperature. The reaction section consists of feed systems, vapori2ers, and/or preheaters which pass a Hquid or gaseous feed mixture over the catalyst bed in the desired ratio, temperature, and pressure. Possible amination catalysts for each method are as foUows. 

Sodium was made from amalgam ia Germany duriag World War II (68). The only other commercial appHcation appears to be the Tekkosha process (74—76). In this method, preheated amalgam from a chlor—alkali cell is suppHed as anode to a second cell operating at 220—240°C. This cell has an electrolyte of fused sodium hydroxide, sodium iodide, and sodium cyanide and an iron cathode. Operating conditions are given ia Table 6. 

Acylates. Titanium acylates are prepared either from TiCl or tetraalkyl titanates. Because it is difficult to obtain titanium tetraacylates, most compounds reported are either chloro- or alkoxyacylates. Under most conditions, TiCl and acetic acid give dichlorotitanium diacetate [4644-35-3]. The best method iavolves passiag preheated (136—170°C) TiCl and acetic acid simultaneously iato a heated chamber. The product separates as an HCl-free white powder (125) ... 

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