Cop systems

The location of the copolymer was studied as a function of the characteristics of the polymers in the blend (e.g., homopolymer molecular weights and copolymer molecular weight and composition) which are related to the a and P of Equations 1 and 2. For a given PS-PI-Cop system, it was found that the location of Cop is practically independent of the amounts of PS, PI, and Cop in the polyblend. Therefore for such a system, two types of blends were generally prepared one rich in PS with PS forming the continuous phase (Blend 1), and one rich in PI with a continuous PI phase (Blend 2). The different fluorescence possibilities are listed in Table IV. If blue fluorescence is observed in the continuous PS phase of Blend 1, it can be inferred that Cop is soluble in PS and in fact the dispersed PS phase of Blend 2 (PI continuous phase) is also fluorescent. 

At about 50% (w/w), phase inversion takes place, and at COP concentrations beyond 50% the formation of LC-rich islands in an LC-poor matrix is observed. These islands have been described by several authors in the COP system [118] and in a blend consisting of a rigid rod and a semiflexible coil polymer [121]. The formation of these islands is mainly due to differences in viscosity and surface tension of LC-poor and LC-rich phases and the tendency to achieve efficient packing by orientation and the lowering of lateral distances of the anisotropic parts of a polymer. The LC-poor (= PC-rich) matrix has a higher melt viscosity than that of COP. In a shear field or under... 

The measure of the system performance is coefficient of performance (COP). For refrigeration applications COP is the ratio of heat removed from the low-temperature level (( Uv) lo the energy input (W) ... 

When dry, or superheated, vapor is used to subcool the liquid, the COP in R12 systems will increase, and decrease the COP in NH3 sys-... 

The COP s of specific air conditioners will vary widely with both manufacturer and application. Electricity utility efficiencies will also differ between countries. However, the reason for the economic interest in heat-driven cycles remains clear. Given that primary fuels can cost the consumer approximately 25% of the cost of electricity and that electricity frequently costs more at times of peak demand, there is justification for considering alternative systems. The use of a primary fuel at the point of use can also reduce COj and other emissions. 

Fig. 6 shows both the actual cycle (shown in dashed lines) and the idealised cycle, which consists of two isosteres and two isobars. Heat flows in J/kg adsorbent q) are shown as shaded arrows. For most purposes, analysis of the ideal cycle gives an adequate estimate of the COP and cooling or heating per kg of adsorbent. An accurate calculation of the path of the actual cycle needs information on the dead volume of the whole system and of the heat transfer characteristics of the condenser and evaporator. General trends are more apparent from an analysis of the idealised cycle. 

Designs should be based on knowledge of what the human body (and human nature) will do. Include educated operators in design reviews. The HAZOP methodology for process hazard analysis offers an excellent opportunity to identify design and procedural opportunities for inherently safer systems. After all, the OP in HAZOP stands for operability (COPS, 1992). For example, a safe start-up procedure that requires the operator to walk up and down the stairs three times to manipulate valves in the correct sequence can be made inherently safer by locating the valves so that operator has to walk up the stairs only once during the start-up. 

There are two major factors that impact the COP temperature difference and system component efficiency. A heat pump requires energy to move heat from a lower temperature to a higher one. As the difference in the two temperatures increases, more energy is required. The COP of a heat pump is high-... 

In the summer, the COP of an air-to-air heat pump decreases as the outdoor temperature rises, reducing the cooling capacity. Normally the thermal needs of the building are met since it is common practice to size a heat pump so that it will deliver adequate cooling capacity in all but the most extreme summer conditions. The winter heating capacity of the system is then determined by this tradeoff, and if the heating capacity is inadequate, supplemental electric or fossil fuel heat is required. 

Bottle washing Closed recirculatory systems Domestic use BEWA COP.0f.85... 

The main application for this cycle is the air-conditioning and pressurization of aircraft. The turbines used for compression and expansion turn at very high speeds to obtain the necessary pressure ratios and, consequently, are noisy. The COP is lower than with other systems [15]. 

Better balance between cooling capacity and load can be obtained by capacity control of the compressor (s). Targe systems will have a number of compressors, or built-in capacity control on the cylinders. A central condensing unit of this sort may be coupled to several fan-coils, each with its own thermostat and liquid solenoid value. The COP is good at all but the lowest load levels. 

In most of these instances the overall reduction in heat flowmay be small, but the cumulative effect within a system maybe enough to reduce the evaporating temperature by as much as 2 K, resulting in a loss in COP of some 6%. 

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