External rendering

The selection of the mortar depends on the background material (i.e., the bricks, blocks or other masonry which is being rendered), the exposure conditions and the required finish. 

Good workability is important to ensure that the mortar is easily applied and can be effectively worked into the joints and crevices of the background material. A high degree of cohesiveness ensures that the mortar adheres to the trowel and to the background. It is also essential when using mechanical spraying equipment. 

A high bond strength to the background material is particularly important. The bond needs to withstand movement between the rendering and the backing material caused by variations in temperature and moisture content. 

Durability results from the use of suitable materials, giving adequate long-term bond strength. 

Renderings are often used to improve the appearance of the building and are treated to give various surface textures and colours. It is therefore essential that the finishing layer is compatible with the proposed finish. 

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The practices described in section 26.6.5 for masonry mortar are appropriate for external rendering mortar. As uniformity of appearance is important in rendered finishes, particular care is necessary to ensure that the materials and proportions are consistent throughout a particular job. 

Although most of the requirements for internal plastering and those for mortar and external rendering are similar, there are several important differences [26.28]. The requirements are described in full, to avoid undue cross-referencing [26.39]. 

A company rendering services in NDT for internal or external customers shall establish and improve the testing quality through management of processes and their interaction. 

The laboratories with sufficient scientific and technical potential may be accredited on the right to develop and/or expert appraisal of the procedures of testing and render their services to external firms. 

Both chloramine-T and dichloramine-T have marked antiseptic properties, chloramine-T being most frequently used because of its solubility in water. Aqueous solutions of chloramine-T can be used either for external application, or for internal application to the mouth, throat, etc, as chloramine-T in moderate quantities is non-toxic its aqueous solution can also be effectively used when the skin has come in contact with many of the vesicant liquid poison-gases, as the latter are frequently organic sulphur or arsenic derivatives which combine with or are oxidised by chloramine-T and are thus rendered harmless. 

Tube-type. These separators are typically divided into two sections (I) precharging and (2) separation. The precharging section is designed to create or enhance the charge difference between particles to be separated (typically by some form of contact mechanism or external pretreatment to render one constituent positive or negative in comparison to the other materials present. The separation section consists of two vertical walls of tubes opposing each other. Each tube... 

This is applicable to both LT and HT capacitors. But it is more important in HT banks, which are relatively much larger and are built of a number of single units eonnected in series-parallel. These may encounter much higher fault currents in the event of a severe internal fault, even in one unit and are thus rendered more vulnerable to such ruptures. This phenomenon is more applicable to units that are externally protected w here (he intensity of fault may be more severe, than internally protected units. 

The theory is initially presented in the context of small deformations in Section 5.2. A set of internal state variables are introduced as primitive quantities, collectively represented by the symbol k. Qualitative concepts of inelastic deformation are rendered into precise mathematical statements regarding an elastic range bounded by an elastic limit surface, a stress-strain relation, and an evolution equation for the internal state variables. While these qualitative ideas lead in a natural way to the formulation of an elastic limit surface in strain space, an elastic limit surface in stress space arises as a consequence. An assumption that the external work done in small closed cycles of deformation should be nonnegative leads to the existence of an elastic potential and a normality condition. 

Optimizing the use of flie external MSA The pinch diagram (Fig. 3.12) demonstrates that below the pinch, the load of the waste stream has to be removed by the external MSA, S3. This renders the remainder of this example identical to Example 2.2. ThereftKc, the optimal flowrate of S3 is 0.0234 kg mol/s and the optimal outlet composition of S3 is 0.(X)85. Furthermore, the minimum total annualized cost of the benzene recovery system is 41,560/yr (see Fig. 2.13). 

At the zinc electrode, zinc ions pass into solution, leaving an equivalent negative charge on the metal. Copper ions are deposited at the copper electrode, rendering it positively charged. By completing the external circuit, the current (electrons) passes from the zinc to the copper. The chemical reactions in the cell are as follows ... 

The green colour due to the Cr3+ ions formed by the reduction of potassium dichromate makes it impossible to ascertain the end-point of a dichromate titration by simple visual inspection of the solution and so a redox indicator must be employed which gives a strong and unmistakable colour change this procedure has rendered obsolete the external indicator method which was formerly widely used. Suitable indicators for use with dichromate titrations include AT-phenylanthranilic acid (0.1 per cent solution in 0.005M NaOH) and sodium diphenylamine sulphonate (0.2 per cent aqueous solution) the latter must be used in presence of phosphoric) V) acid. 

However, the source of MU water for higher pressure steam-raising plants is important because it is generally the case that no matter the origin of the water, it will not be entirely suitable for the purpose and some form of water conditioning will be required. This conditioning requirement necessitates the provision of a (pre-boiler section) water pretreatment plant system (external treatment/external conditioning) to render the water fit for purpose. 

Before an antibacterial agent can exert its effect on a cell it must eombine with that eell. This process often follows the pattern of an adsorption isotherm. Clearly, faetors whieh affect the state of the cell surface, as the pH of the eelTs environment must do, must affect, to some extent, the adsorption process. An inerease in the external pH renders the cell surface more negatively charged. Bioeidal agents that are eationie in nature thus bind more strongly to the cell surface with a eonsequent inerease in aetivity. 

Alternative mechanisms are equally likely. One possibility arises from evidence that activation of a2-adrenoceptors reduces Ca + influx this will have obvious effects on impulse-evoked exocytosis. In fact, the inhibition of release effected by a2-adrenoceptor agonists can be overcome by raising external Ca + concentration. Finally, an increase in K+ conductance has also been implicated this would hyperpolarise the nerve terminals and render them less likely to release transmitter on the arrival of a nerve impulse. Any, or all, of these processes could contribute to the feedback inhibition of transmitter release. Similar processes could explain the effects of activation of other types of auto-or heteroceptors. 

Three main properties render clay suitable for making ceramic materials its plasticity when wet, its hardness when dry, and the toughness, increased hardness, and stability that it acquires when fired. The addition of water to dry clay produces a clay-water mixture that, within a narrow range of water content, has plastic properties it is deformed, without breaking or cracking, by the application of an external stress, and it retains the acquired shape when the deforming stress is removed. Wet clay mixtures can, therefore, be modeled, molded, or otherwise made to acquire a shape that will be retained after the forming operations. Water-poor mixtures are not plastic, however, and excess water results in mixtures, known as slips, that are too fluid to retain a shape, as shown in Table 56. 

It should be noted immediately that not all the frequencies absorbed by a semiconductor are photocatalytically active, but only those that are also photoelectrically active, i.e., that cause an internal photoelectric effect in the semiconductor. Note further that the sign and magnitude of the photo-catalytic effect depend on the past history of the specimen exposed to illumination i.e., they depend on the external influences to which the specimen in question was subjected in the course of the whole of its life, and also on the conditions of the experiment (temperature, intensity of illumination, etc.). For example, by introducing into the semiconductor an impurity of any concentration or by adsorbing foreign gases on its surface it is possible to render its catalytic activity more or less sensitive to illumination. 

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