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A-directing influence

The global geochemical background and enormous industrial environmental pollution have increased, thus, there are all the bases to speak about the beginning of biogeochemical formation development which has a direct influence on the ecological system condition in general as well as on the population health. [Pg.77]

Corrosivity of the water has a direct influence on erosion-corrosion susceptibility. Opportunities for reduction of corrosivity are often limited, but the following are offered as guidelines ... [Pg.250]

As indicated above, national policies and international conventions have been invoked to curb known, and usually obvious, sources of marine pollution. National legislation is used to control coastal discharges of contaminants. A major problem remains owing to the inadequate treatment of sewage prior to emission from land-based sources. The most important deleterious effects in this case are with respect to microbial water quality. This can have a direct influence on bathing criteria and result in beach closures during contamination episodes. An additional problem from land-based sources pertains to transboundary effects, whereby pollution may inadvertently be exported from one country to another. [Pg.89]

The temperature of pressing has also a noticeable effect [226,227] as it does influence the surface/core temperature gradient and has a direct influence on the temperature rise in the board core layer. In short, the higher the press temperature, the faster the heat conduction and the faster the development of the steam gradient across the wood mat. The press temperature will influence the steam front transfer time to the core layer. The higher the initial temperature, the faster the steam front enters the mat core. Increasing the press temperature will cause the maximum steam pressure peak to appear earlier but does not result in a higher core temperature. [Pg.1095]

Dust porosity The porosity of the dust cake, which has a direct influence on the filter pressure drop. [Pg.1432]

Comparing the reactivity of the catalysts (Fig.l and Table 1), the -OH substituted catalyst showed highest activity with EAS and the least to -OMe substituted catalyst. But with MAO the trend was reversed. Even though it is difficult to establish a direct influence for these push-pull substituents on the metal center, their roles have been try to investigate by cyclic... [Pg.855]

An advantage of nickel catalysts over other metal systems is that the properties of the active species can easily be tuned by the addition of suitable ligands. For example, the presence of PPhj was shown to have a direct influence on the regiochem-istry of hydroalumination of 1,1-dimethylindene la [33]. While the reaction of BU2AIH with la gave a 4 1 mixture of regioisomeric products 13a/13b after deuterolytic workup, the same reaction carried out in the presence of PPh, yielded 13a and 13b in a ratio of >99 1 (Scheme 2-14). [Pg.60]

This allows a direct influence of the alloying component on the electronic properties of these unique Pt near-surface formations from subsurface layers, which is the crucial difference in these materials. In addition, the electronic and geometric structures of skin and skeleton were found to be different for example, the skin surface is smoother and the band center position with respect to the metallic Fermi level is downshifted for skin surfaces (Fig. 8.12) [Stamenkovic et al., 2006a] owing to the higher content of non-Pt atoms in the second layer. On both types of surface, the relationship between the specific activity for the oxygen reduction reaction (ORR) and the tf-band center position exhibits a volcano-shape, with the maximum... [Pg.259]

The dielectric constant e has a direct influence on Cp and influences k indirectly, so the presence of non-aqueous solvent, if any, will be of great importance. [Pg.37]

Thus, loops, utility paths and stream splits offer the degrees of freedom for manipulating the network cost. The objective function in new design is usually to minimize total cost, that is, combined operating and annualized capital cost. The annualization period chosen for the capital cost will have a direct influence on the optimization. A longer annualization period will lead to more energy-efficient designs. [Pg.414]

The bystander substituent (Y) exerts a direct influence on the migrant group (M) at the migration origin. In contrast, a spectator substituent (X in Eq. 22)... [Pg.81]

Note (1) The temperature of the flame and the composition of the flame afford a direct influence on interferences which may give rise to erroneous results,... [Pg.362]

The real density of coke is obtained when the particle size of the specimen is smaller than 75 mm. The real density (or the particle size) exerts a direct influence on the physical and chemical properties of the carbon and graphite products that are manufactured from the coke. [Pg.299]

Ofher diffusion layer approaches can also be found in the literature. Chen-Yang et al. [81] made DLs for PEMFCs out of carbon black and unsintered PTFE comprising PTFE powder resin in a colloidal dispersion. The mixture of fhese materials was then heated and compressed at temperature between 75 and 85°C under a low pressure (70-80 kg/cm ). After this, the DLs were obtained by heating the mixture once more at 130°C for around 2-3 hours. Evenfually, fhe amount of resin had a direct influence on determining the properties of fhe DL. The fuel cell performance of this novel DL was shown to be around a half of that for a CFP standard DL. Flowever, because the manufacturing process of these carbon black/PTFE DLs is inexpensive, they can still be considered as potential candidates. [Pg.223]

To design the optimal diffusion layer for a specific fuel cell system, it is important to be able to measure and understand all the parameters and characteristics that have a direct influence on the performance of the diffusion layers. This section will discuss in detail some of the most important properties that affect the diffusion layers, such as thickness, hydrophobicity and hydrophilicity, porosity and permeability (for both gas and liquids), electrical and thermal conductivity, mechanical properties, durability, and flow... [Pg.248]

The failure in increasing residence time of mucoadhesive systems in the human intestinal tract has led scientists to the evaluation of multifunctional mucoadhesive polymers. Research in the area of mucoadhesive drug delivery systems has shed light on other properties of some of the mucoadhesive polymers. One important class of mucoadhesive polymers, poly(acrylic acid) derivatives, has been identified as potent inhibitors of proteolytic enzymes [72-74]. The interaction between various types of mucoadhesive polymers and epithelial cells has a direct influence on the permeability of mucosal epithelia by means of changing the gating properties of the tight jrmctions. More than being only adhesives, some mucoadhesive polymers can therefore be considered as a novel class of multifunctional macromolecules with a number of desirable properties for their use as delivery adjuvants [72,75]. [Pg.184]

Sulfur impurities can be detrimental to nickel deposits. Specifically, an increase in sulfur couteut is known to reduce the fracture resistance of electroformed nickel. Since sulfur has a direct influence on the properties of electrodeposited nickel, if no other impurities are present in the deposit, hardness by itself can be used as an indicator of sulfur impurity content. [Pg.285]

In the case of cyclooctene oxide 24, the nature of the base used has a direct influence on the competition between a- and /3-deprotonation, as already discussed in Section 11. [Pg.1219]

Studying the transition from (semi)metallic to ionic stmctures. It became evident that the use of different or different combinations of electropositive metals led to variations in size and shape of the polyanionic moiety. For some elements this was extensively studied, and a direct influence of cation-element interaction on size, structure, and functionahty of the polyanions was emphasized. These interactions are naturally strong for small cations and become less strong the higher the period, in accord with the corresponding radii. [Pg.27]

The level of definition of a project during the FEL phases has a direct influence on the projects ultimate outcome in terms of the number and impacts of changes in the EPC phase. This level of FEL performance translates to fewer major changes in engineering, construction, and during start-up (Merrow, E. W., Independent Project... [Pg.45]


See other pages where A-directing influence is mentioned: [Pg.219]    [Pg.276]    [Pg.184]    [Pg.330]    [Pg.991]    [Pg.1251]    [Pg.667]    [Pg.93]    [Pg.47]    [Pg.258]    [Pg.19]    [Pg.64]    [Pg.157]    [Pg.249]    [Pg.210]    [Pg.274]    [Pg.232]    [Pg.26]    [Pg.231]    [Pg.13]    [Pg.107]    [Pg.108]    [Pg.76]    [Pg.152]    [Pg.394]    [Pg.284]    [Pg.259]    [Pg.141]    [Pg.201]    [Pg.92]   
See also in sourсe #XX -- [ Pg.136 , Pg.137 , Pg.138 , Pg.147 ]




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A direct

Directing influence

Influence, directive

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