Dual systems

Starch is a polysaccharide found in many plant species. Com and potatoes are two common sources of industrial starch. The composition of starch varies somewhat in terms of the amount of branching of the polymer chains (11). Its principal use as a flocculant is in the Bayer process for extracting aluminum from bauxite ore. The digestion of bauxite in sodium hydroxide solution produces a suspension of finely divided iron minerals and siUcates, called red mud, in a highly alkaline Hquor. Starch is used to settle the red mud so that relatively pure alumina can be produced from the clarified Hquor. It has been largely replaced by acryHc acid and acrylamide-based (11,12) polymers, although a number of plants stiH add some starch in addition to synthetic polymers to reduce the level of residual suspended soHds in the Hquor. Starch [9005-25-8] can be modified with various reagents to produce semisynthetic polymers. The principal one of these is cationic starch, which is used as a retention aid in paper production as a component of a dual system (13,14) or a microparticle system (15). 

Microparticulate Systems - Although dual combination treatment systems comprising microparticles and flocculants have been used in the paper industry since the 1980s, it is only recently that there has been a general trend for paper mills to switch from conventional single component systems to dual systems. 

The lubricating oil system for a turbine is very important and is nearly always provided with a dual pumping arrangement. One pump can be driven directly off the turbine shaft and the other by separate electric motor or steam turbine. In another arrangement, one pump can be separately electric driven and the other separately steam turbine driven. Twin coolers are often provided in the dual system to... 

APME WURZBURG,UNIVERSITY DOW CHEMICAL EUROPE DUALES SYSTEM DEUTSCHLAND... 

BASF AG DUALES SYSTEM DEUTSCHLAND OTTO GMBH... 

NOTE If primacord is in short supply, a single strand of primacord with two knots tied on it may be used in place of the dual system described and illustrated. 

A new composite containing montmorillonite and zeolite Beta is prepared by in situ crystallization. Nano-zeolite Beta grows on montmorillonite. The composite possesses a dual system of micropore, originated from zeolite Beta, and mesopore of size around 50nm, due to the abundance of interspace formed by montmorillonite laminaes. Compared with catalyst MoNi/Beta, more i-C8 is produced on catalyst MoNi/composite, when n-Cg is used for feedstock for hydroisomerization. This results from the high diffusion created by composite and the short channel of nano-size zeolite Beta. 

When using PFT with a neutral selector, it is quite difficult to avoid any entrance of the chiral selector into the ionization source, particularly at a high pH, where EOF is important. The use of BGE at low pH and/or coated capillary to minimize EOF is therefore mandatory. However, the coaxial sheath gas, which generally assists the ionization process, leads to an aspirating phenomenon of the chiral selector in the MS direction. Javerfalk et al. were the first to apply PFT with a neutral methyl-/i-CD for the separation of racemic bupivacaine and ropivacaine with a polyacrylamide-coated capillary and an acidic pH buffer (pH 3). Cherkaoui et al. employed another neutral CD (HP-/1-CD) with a PVA-coated capillary for the analysis of amphetamines and their derivatives. To prevent a detrimental aspiration effect, analyses were carried out without nebulization pressure. Numerous other studies presented excellent results such as the enantioselective separation of adrenoreceptor antagonist drugs using tandem mass spectrometry (MS/MS) the separation of clenbuterol enantiomers after solid-phase extraction (SPE) of plasma samples or the use of CD dual system for the simultaneous chiral determination of amphetamine, methamphetamine, dimethamphetamine, and p-hydroxymethamphetamine in urine. 

TT-system can easily be realized (see schematic representation on page 53). (Ni part of the double-dual system shown below ... 

Each heliostat is designed to illuminate a specific area on the parabola and is equipped with a dual optical control system, which maintains the proper orientation for each hcliostat by means of a dual hydraulic system. This dual system permits each heliostat lo be operated in either a search or track mode. In both cases, the optical guidance system uses an optical tube, which contains four photodiodes that control the heliostat motion in east-west and up-down direction. 

Carballo-Jane E, Pandit S, Santoro JC, et al. Skeletal muscle a dual system to measure glucocorticoid-dependent transactivation and transrepression of gene regulation. J Steroid Biochem Mol Biol. 2004 88 191-201. 

It is possible to classify dyes by using the Color Index that classifies dyes according to a dual system. An assigned number defines the chemical class and a generic name identifies the usage of application. However, it is convenient to use the application classification used by the U.S. International Trade Commission for application classes ... 

Ethanol Feed. The ethanol was fed by a dual system. The first was a two flask feed system, used to maintain an ethanol base line feed rate. Each flask contained 4000 ml of ethanol solution. Flask one contained 125 ml of 190 proof ethanol (93.7 g) in 3875 ml of H2O. Flask two contained 3500 ml of 190 proof ethanol (2623 g) plus 500 ml of water. When the system is feeding solution from flask one to the fermenter at a constant rate, r liter/hr, a linear increase in alcohol concentration in the feed will occur. See Figure 2 for details. This will result in a cell mass increase in the fermenter that is second order in time. This base line feed rate will always be less than the desired growth rate as long as the correct feed rate is selected. 

A real plastic waste collected by the German Dual System (DSD) from municipal packaging waste was pyrolyzed in the laboratory plant as well as in the pilot plant. The composition of the mixed plastic wastes is shown in Table 17.4. 

Often dual chiral recognition systems ]462,463] involving mixtures of chiral SOs have been shown to enhance enantioselectivity. With dual systems of cyclodextrins (CDs), cationic mono(6-amino-6-deoxy)-p CD and a neutral CD (trimethyl-p-CD or dimethyl-p CD), it could be illustrated that arylpropionic acid enantiomers were baseline resolved, while with a single SO, no or insufficient separation of the enantiomers could be achieved [462J. 

Ion-exclusion chromatography can couple to ion chromatography to improve the chromatographic resolution of inorganic anions and organic acids in complex matrices. The dual system can be either in the order lEC/IC or IC/IEC. 

Although the work reported in this paper has been concerned with combinations of two degrading additives, systems involving three or more additives are being investigated. Even faster rates than were obtained with dual system can be achieved. With three additives and using a typical ternary composition graph, contour lines can be plotted and the area of maximum effectiveness determined quickly. Princeton Polymer... 

Ordinance is the legal basis for the work of the private company DSD (Duales System Deutschland). It searches and contracts companies involved in recycling plastics, pays them and collects a licence fee from every producer of goods. This is dependent on the weight of the total packaging material and the number of pieces produced. The producer of the original packaging material also has to pay a licence fee. 

A dual system of healthcare has been instituted, consisting of both public and private healthcare systems. The public system provides about 20 percent of primary healthcare and 80 percent of hospital care, while the private system provides 80 percent of primary health services and 20 percent of hospital services. 

In all cases, the pressure used should be the lowest which will do the work. This saves first cost, power and time. In many instances a part of an operation can be performed at low pressure, the finish only requiring high pressure. This dual system may be provided by a complete duplication of pumps, accumulators and piping, with manual or automatic transfer valves, or intensifiers may be used at points of fluid consumption. These are pumps using the low-pressure fluid as the actuating medium in what corresponds to the steam cylinder, to produce a local excess pressure. 

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