Evaporation, residue

Existent gums NF EN 26246 ISO 6246 ASTM D 381 Weight of evaporated residue... 

A sample to be examined by electrospray is passed as a solution in a solvent (made up separately or issuing from a liquid chromatographic column) through a capillary tube held at high electrical potential, so the solution emerges as a spray or mist of small droplets (i.e., it is nebulized). As the droplets evaporate, residual sample ions are extracted into a mass spectrometer for analysis. 

The 35 and 50% H2O2 concentrations are used for most industrial appHcations. The standard grades contain sufficient stabilizers to ensure safety. Grades having lower stabilizer content and evaporative residue are available for specialty uses and for aseptic cleansing of containers in food processing and marketing. 

The crude product separates as a solid from the reaction medium and is recovered by filtration, and it is then washed thoroughly with ether and dissolved in 350 ml 1 N HCI. Then, approximately 250 ml of the aqueous solvent is removed with a rotary evaporator and the evaporation residue combined with 125 ml methanol and filtered through decolorizing charcoal. The product is precipitated as the HCI salt by the addition of 7 parts of acetone. The resulting crystalline material is removed by filtration dried at 40°C with vacuum, and has a melting point of about 242°C and Is used without further purification. 

Toluene (99.8% anhydrous, water <0.001%, evaporation residue <0.005%) was purchased from Aldrich Chemical Company and used as received. The capacity of the receiver in the Dean-Stark trap was 28 mL. The initial amount of toluene placed in the flask was 88 mL. Upon heating to reflux, 28 mL of toluene was distilled from the flask and collected in the receiver. The remaining volume of toluene in the reaction flask was ca. 60 mL, corresponding to an approximately 0.50M concentration of the reactants. 

The main mineral components of baghouse dust are silica, clay, some resin evaporation residue, and metal fines. Its composition is related to the way it is collected. Shake-out dust mainly contains silica and clay. Metal fines may be present in the dust collected from areas used for cleaning, grinding, and melting processes. 

The evaporated residue from sensitised photochemical oxidation of the polyene ignited spontaneously, on several occasions explosions occurring. 

Urine Extract compound from urine using diethyl ether wash with HC1, dry over anhydrous Na2S04, filter evaporate diethyl ether dissolve evaporated residue with diethyl ether HPLC/UV GC/MS NR NR Albro and Moore 1974 Albro et al. 1973... 

Blood and tissue samples Mix blood sample with HC1 and hexane homogenize tissue sample and mix with HC1 and hexane evaporate hexane dissolve evaporated residue with methanol 1 HPLC NR NR Oishi 1990... 

Figure 6. Plot of experimental products from evaporation of chondrules in the laboratory (Young et al. 2002b). The four data points below = 0.0 are the starting materials. The evaporative residues exhibit...

Liquid chromatographic methods based on ultraviolet and/or electrochemical detection have also been developed (622-625). In the earliest of these methods (623), tissues were extracted with mcthanol/water (1 1), and the evaporated residue was taken up in dichloromethanc. The extract was then injected on a Kieselgel Merckosorb SI-60 liquid chromatographic column, and eluted with dichloromethane/ethanol/water. Monitoring at 280 nm allowed 5 ppb thiouracils to be readily detected in the tissue samples. In the latest method (625), cattle plasma samples were extracted with etliyl acetate in presence of ethylenediamine-tetraacetate (EDTA). The addition of ED I A could significantly improve the efficiency of the extraction process. Remarkable improvement of the ethyl acetate... 

The cross section for production of a heavy evaporation residue, ctEVr, by a complete fusion reaction can be written as ... 

RECOILS, EVAPORATION RESIDUES (EVRs), AND HEAVY RESIDUES 591... 

When these heavy recoil nuclei are the result of a complete fusion of the projectile and target nuclei, they are usually called evaporation residues because they result from a deexcitation of the primary complete fusion product by particle evaporation (emission). In intermediate energy and relativistic nuclear collisions, the momentum transfer to the target nucleus is much less, and the energy of the recoiling nucleus is 5-100 keV/nucleon. Such recoils are usually called heavy residues ... 

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