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Later injection

One of the attractive features of SFE with CO2 as the extracting fluid is the ability to directly couple the extraction method with subsequent analytical methods (both chromatographic and spectroscopic). Various modes of on-line analyses have been reported, and include continuous monitoring of the total SFE effluent by MS [6,7], SFE-GC [8-11], SFE-HPLC [12,13], SFE-SFC [14,15] and SFE-TLC [16]. However, interfacing of SFE with other techniques is not without problems. The required purity of the CO2 for extraction depends entirely on the analytical technique used. In the off-line mode SFE takes place as a separate and isolated process to chromatography extracted solutes are trapped or collected, often in a suitable solvent for later injection on to chromatographic instrumentation. Off-line SFE is inherently simpler to perform, since only the extraction parameters need to be understood, and several analyses can be performed on a single extract. Off-line SFE still dominates over on-line determinations of additives-an... [Pg.429]

Problem No. 8 Peaks Tail on Initial and Later Injections... [Pg.123]

For development of a weight percent assay, a short isocratic method can be implemented based on observations from the gradient method used for the impurity profile. One can use a shorter column such as a 5-cm column and keep retention of the solute of interest to around a capacity factor of 3 as long as it is still resolved from impurities observed in the impurity prohle. Additionally, the elution of more hydrophobic species should not co-elute with the drug substance in later injections. During the method development of an isocratic method, the compound should be injected and then a suitable number... [Pg.659]

These antigens are commonly administered by frequent, intravenous injection without adjuvant. Results are obtained quickly, the antisera often containing a high proportion of IgM immunoglobulin. There is a risk both of direct toxicity early in immunization and of severe hypersensitivity reactions as a result of later injections. With some at least of the antigens in question, equally satisfactory results can be obtained by intramuscular injection of Freund s emulsions—immunization is slower but less risky. [Pg.117]

Laterally injected dikes of distinct composition Fractured and tilted dikes of distinct composition... [Pg.1717]

Bradycardia and other dysrhythmias are common (80% in some series) and occur after the first and subsequent injections of suxamethonium in infants and children. In adults, these effects are seen more commonly after second or later injections, particularly when the interval between the doses is 2-5 minutes. However, it has been suggested that bradycardia and asystole may now be more frequently seen than previously in adults after a single injection of suxamethonium, as a result of the increased use of fentanyl or the omission of atropine beforehand (6). Nodal rhythm and wandering pacemaker are frequent. The bradycardia is sometimes extreme (asystoUc periods of 15-30 seconds duration have been reported). Usually these minor dysrhythmias revert to normal after a few minutes. Halothane can prolong their presence. The incidence of bradycardic asystole is not known, as atropine (the effective therapy) is usually quickly given. [Pg.3255]

AIGalnP LEDs, (b) Current crowding in a mesa-structured GaN-based LED grown on an insulating substrate, (c) Lateral injection geometry. The corresponding equivalent circuits are shown as well. [Pg.16]

The roles of Ras-related proteins were revealed by simple microinjectlon experiments. When Rac was mlcroln-jected into a fibroblast, the membrane immediately started to form upward projections called ruffles focal adhesions and stress fibers formed 5-10 minutes later. Injection of an inactive form of Rac inhibited all reorganization of the actin cytoskeleton when growth factors were added to the cell. When Rho, rather than Rac, was injected, it mimicked the mitogenic effects of lysophosphatidic acid (LPA), a chemokine in serum and a potent stimulator of platelet aggregation. Both Rho and LPA induced the assembly of stress fibers and focal adhesions within 2 minutes but did not induce membrane ruffling. [Pg.803]

The nozzle represents the outer hmit of the injection- or ante-chamber (i.e., the space in front of the screw tip). The material is later injected through the nozzle and into the mold. However, no material should escape from the nozzle... [Pg.36]

Forty-six to 48h later, inject the same mice ip with 100 oL of 50-IU/mL hCG (5 lU/ mouse). Immediately place each female with a male stud. [Pg.81]

Compressor performance parameters follow basic dimensional analysis and similarity rules which allow to design and test stages at some reference conditions and then apply them at actual (dimensional) conditions. If it were 100% rigorously followed, this process would guarantee a perfect matching of the performance. Unfortunately, in real life this is not always possible for several reasons such as lirst and last stage effects, lateral injections, difSculty of matching Reynolds number, etc. Thus, some corrections are needed to move from the performance stored in the database to the actual machine. There is a trade-off between the complexity of the database and the amount of adaptations which are needed (Fig.14). [Pg.239]

If the concentration of cadmium in a sample solution is too low for quantitation by this flame AAS analytical technique, and the sample is to be averaged with other samples for TWA calculations, aliquots of the sample and a matrix modifier are later injected onto a Lvov platform in a pyrolytically-coated graphite tube of a Zeeman atomic absorption spectrophotometer/graphite furnace assembly for analysis of elemental cadmium. The matrix modifier is added to stabilize the cadmium metal and minimize sodium chloride as an interference during the high temperature charring step of the analysis (5.1., 5.2.). [Pg.1007]

At the beginning of the reaction, the first species observed was intermediate 163, which may proceed from the intermediate 164. It was suggested that 164 was the result of an oxidative addition of acetic acid to a Pd(0) complex In a later injection. [Pg.254]

To illustrate the hyphenation between FIA and HPLC, a system for food additives (acesulfame-k, saccharin, caffeine, benzoic acid and sorbic acid) determination [40] is shown in Figure 3.14. The system includes a dialysis cell in order to eliminate the sample matrix. Thus, a peristaltic pump dispenses the sample, which is loaded into a holding coil of an injection valve (IVl) and later injected into the donor stream. Both, donor and acceptor streams are also propelled by the peristaltic pump. Once the dialysis has been performed, analytes are loaded into a holding coil of a second injection valve (IV2). At this point, the sample passes to the HPLC system. The sample is injected into a mobile phase stream dispensed by the HPLC pump. So, the pretreated sample passes through the precolumn and column, and the analytes are separated and detected. Thus, the treatment, separation and detection steps are carried out in an efficient and high automated way. [Pg.80]

The other path would be to lower the engine-out NOx to the legislated value with later injection timing and cooled EGR. This would lead to higher soot from the combustion and higher fuel consumption. A DOC (diesel oxidation catalyst) and/or a DPF (diesel particulate filter) are then used in order to reduce the particulates to the legislated value (Fig. 3.2). [Pg.66]

Tsai, M.K., Liou, T.M., 1991. Study of flow induced by nonuniform lateral injection. J. Propul. 7, 668-677. [Pg.454]

Figure 8.29. Cumulative oil recovery and watercut profiles for later injection of biopolymer compared with waterflooding in the Brent Sands cross-section (Sorbie et al, 1982). Figure 8.29. Cumulative oil recovery and watercut profiles for later injection of biopolymer compared with waterflooding in the Brent Sands cross-section (Sorbie et al, 1982).
Shortly before the cavity the runner of the tunnel gate leads into an angled drilling entering tunnel- like the cavity (Figure 1.36). Therefore, prerequisite for the application is the existence of a side or facing surface, which will accept the gate. A lateral injection will be necessary if the part has not a convenient aperture. [Pg.52]

Wells O.S. 9 and 27 in Oerrel have produced two oil banks. The first bank was formed by a lower viscosity oil bank, because the polymer moving over a large distance was partly stripped of polymer due to adsorption and some dilution. The later injection in Well O.S. 57 could form a viscous polymer bank to displace additional oil from a previously polymer-flooded area (Fig. 15). [Pg.314]


See other pages where Later injection is mentioned: [Pg.109]    [Pg.40]    [Pg.255]    [Pg.26]    [Pg.705]    [Pg.660]    [Pg.135]    [Pg.206]    [Pg.1015]    [Pg.305]    [Pg.476]    [Pg.434]    [Pg.5]    [Pg.108]    [Pg.60]    [Pg.434]    [Pg.4]    [Pg.242]    [Pg.484]   
See also in sourсe #XX -- [ Pg.291 ]




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