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SHIP technique

One approach to recovery of useful plant metabolites such as rosmarinic acid is to extract plants as they are currently produced. Unfortunately the agronomic conditions for production of such plants are extremely variable. Unreliable cultivation, harvesting, shipping techniques, infestation with pests and natural status of the plant can all impart the lost of the product produced by the plant (6). Changes in any of these conditions can adversely influence the production of compounds such as rosmarinic acid. The application of modem culturing of plant cells offers an alternative means of production. Conditions of culturing can be optimized such that a cell culture would produce rosmarinic acid on a continuous basis at high yield and in a form where it can be easily extracted (7). [Pg.235]

Laser Doppler Velocimeters. Laser Doppler flow meters have been developed to measure Hquid or gas velocities in both open and closed conduits. Velocity is measured by detecting the frequency shift in the light scattered by natural or added contaminant particles in the flow. Operation is conceptually analogous to the Doppler ultrasonic meters. Laser Doppler meters can be appHed to very low flows and have the advantage of sensing at a distance, without mechanical contact or interaction. The technique has greatest appHcation in open-flow studies such as the deterrnination of engine exhaust velocities and ship wake characteristics. [Pg.67]

Several methods have received considerable research attention as alternatives to salt curing. These include use of sodium bisulfite as a disinfectant to allow preservation with or without decreased salt in a brine cure use of disinfectants such as quatenary amines for temporary preservation in direct shipping to the taimery from the packing plant (see Disinfectants and antiseptics) preservation of hides by radiation sterilization (see Sterilization techniques) and substitution of materials such as potassium chloride for sodium chloride. These methods have found only limited commercial success. [Pg.83]

The relationship between the stmcture of a molecule and its physical properties can be understood by finding a quantitative stmcture—property relation- ship (QSPR) (10). A basis set of similar compounds is used to derive an equation that relates the physical property, eg, melting poiat or boiling poiat, to stmcture. Each physical property requires its own unique QSPR equation. The compounds ia the basis set used for QSPRs with pyridines have sometimes been quite widely divergent ia respect to stmctural similarity or lack of it, yet the technique still seems to work well. The terms of the equation are composed of a coefficient and an iadependent variable called a descriptor. The descriptors can offer iasight iato the physical basis for changes ia the physical property with changes ia stmcture. [Pg.324]

Economic Aspects. Table 13 summarizes prices and shipping methods for the principal borate products as of January 1991. Within the United States most shipments are by rail, and additional charges are made for spHt cars, tmck shipments, palletized shipments, etc. Prices are fob Southern California. In general, the borates are stable soHds and require no special handling techniques with the possible exception of dust collection. [Pg.203]

Burns, R.S. (1997) The Application of Artificial Intelligence Techniques to Modelling and Control of Surface Ships. In Proc. 11th Ship Control Systems Symposium, Southampton UK, April, 1, 77-83. [Pg.428]

Grimble, M.J., Patton, R.J. and Wise, D.A. (1979) The design of dynamic ship positioning control systems using extended Kalman filtering techniques, IEEE Conference, Oceans 79, CA, San Diego. [Pg.430]

Shipping analysis is an extremely sensitive electrochemical technique for measuring trace metals (19,20). Its remarkable sensitivity is attributed to the combination of an effective preconcentration step with advanced measurement procedures that generate an extremely favorable signal-to-background ratio. Since the metals are preconcentrated into the electrode by factors of 100 to 1000, detection limits are lowered by 2 to 3 orders of magnitude compared to solution-phase voltammetric measurements. Hence, four to six metals can be measured simultaneously in various matrices at concentration levels down to 10 10 i. utilizing relatively inexpensive... [Pg.75]

Essentially, stripping analysis is a two-step technique. The first, or deposition, step involves die electrolytic deposition of a small portion of the metal ions hi solution into die mercury electrode to preconcentrate the metals. This is followed by die shipping step (the measurement step), which involves die dissolution (shipping) of die deposit. Different versions of stripping analysis can be employed, depending upon die nature of the deposition and measurement steps. [Pg.76]

Zeolites have ordered micropores smaller than 2nm in diameter and are widely used as catalysts and supports in many practical reactions. Some zeolites have solid acidity and show shape-selectivity, which gives crucial effects in the processes of oil refining and petrochemistry. Metal nanoclusters and complexes can be synthesized in zeolites by the ship-in-a-bottle technique (Figure 1) [1,2], and the composite materials have also been applied to catalytic reactions. However, the decline of catalytic activity was often observed due to the diffusion-limitation of substrates or products in the micropores of zeolites. To overcome this drawback, newly developed mesoporous silicas such as FSM-16 [3,4], MCM-41 [5], and SBA-15 [6] have been used as catalyst supports, because they have large pores (2-10 nm) and high surface area (500-1000 m g ) [7,8]. The internal surface of the channels accounts for more than 90% of the surface area of mesoporous silicas. With the help of the new incredible materials, template synthesis of metal nanoclusters inside mesoporous channels is achieved and the nanoclusters give stupendous performances in various applications [9]. In this chapter, nanoclusters include nanoparticles and nanowires, and we focus on the synthesis and catalytic application of noble-metal nanoclusters in mesoporous silicas. [Pg.383]

Some more recent field techniques have focused on the location of the preparation of field fortification samples and have taken some of the responsibility for the preparation of the field fortification samples from the field personnel and placed them with the analytical laboratory. For example, it is becoming more common for the analytical laboratory to prepare air sample field fortifications in the analytical laboratory, freeze them, and ship them to the field for use in a frozen state. Whereas there may be some advantage to this technique in that the air tube fortification samples may possibly be fortified more accurately in the laboratory under controlled conditions than if done in the field, there are some inherent scientific problems with this method. First, one reason for the field fortification is to test the ruggedness of the field techniques of the researcher under extreme field conditions. Second, the act of freezing and thawing the sorbent matrix within the air mbe itself may have an impact on the recovery of the analyte from the air tube after exposing the sorbent to field conditions... [Pg.1014]


See other pages where SHIP technique is mentioned: [Pg.57]    [Pg.57]    [Pg.980]    [Pg.1051]    [Pg.693]    [Pg.341]    [Pg.524]    [Pg.411]    [Pg.435]    [Pg.324]    [Pg.47]    [Pg.559]    [Pg.269]    [Pg.126]    [Pg.299]    [Pg.397]    [Pg.366]    [Pg.2243]    [Pg.318]    [Pg.9]    [Pg.1144]    [Pg.1283]    [Pg.112]    [Pg.345]    [Pg.699]    [Pg.32]    [Pg.133]    [Pg.648]    [Pg.655]    [Pg.539]    [Pg.84]    [Pg.181]    [Pg.30]    [Pg.598]    [Pg.147]    [Pg.297]    [Pg.619]    [Pg.870]    [Pg.1013]   
See also in sourсe #XX -- [ Pg.1283 ]

See also in sourсe #XX -- [ Pg.1283 ]




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