Influences of some factors

For nano HAP product, its size and distribution and appearance of the particles are the major quantity indexes. In addition, chemically the mole ratio of Ca/P essentially characterizes the purity of the product. All these are taken as the criteria for comparison and analysis of the experimental results. 

The results given in both Table 16.2 and Fig. 16.2 suggest that a certain back-flow (keeping warm) time after reaction-precipitation inside the SCISR is necessary for full double decomposition and/or, probably, surface deactivation of the newly formed particles, while too long a back-flow time leads to the product becoming worse in both purity and appearance. From the results given in Table 16.2 and Fig, 16.2, three to four hours can be considered to be the optimal condition for the back-flow (ageing) time. 

The results of the influence of the pH of the reaction mixture on the Ca/P mole ratio of the product are illustrated in Table 16.3. As can be seen in the table, the mole ratio of Ca/P increases as the pH decreases so it can be concluded that pH is an important factor affecting the composition or purity of the product. 

As is well known, in addition to HAP, there are three solid products with different Ca/P ratios which can possibly be combined in the product under various pH conditions yielding variation of the Ca/P mole ratio in the product during precipitation Ca(OH)2 of Ca/P = oo, Ca,(P04)2 of Ca/P = 1.5, and CaHP04 of Ca/P = 1.0. 

Chemically, the data listed in Table 16.3 should lead to the following inference in the range of pH tested  

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Despite the widespread cultivation and use of potatoes, very little is known about the influence of some factors on their GI and RGI, whereas some obvious factors, such as starch structure and processing, have been subjected to a limited amount of research. 

Although the influences of some factors are self-evident, if experimental data are sparse, it can be difficult to determine all the significant factors. Experience will help provide a list of candidates, and the suite of factors to be investigated will be constrained by the time and effort available. At first, the linear coefficients of the model will give most information about the... 

Kodgev, A. and Rachev, R. 1070. The influence of some factors on the acidity of milkfat. 18th Int. Dairy Congr. Proc. IE, 200. 

The most important characteristics involved in pressure fluctuation are the frequency and the amplitude and must therefore be the major focus of investigation into pressure fluctuation. In addition, it is necessary to understand the distributions of the frequency and the amplitude of fluctuation over the space inside the reactor and the influences of some factors on them. 

Experimental methods often provide the integral characteristics of a system, but do not detect the influence of some factors. Quantum chemical methods provide an opportunity to perform calculations such that the role of some factors becomes apparent through the entire multistage mechanism of interaction between a silica nanoparticle and biologically active molecules.4... 

PVC is often used in food packaging and blood bags. This study concerns mass transfers between plasticised PVC, having been subjected to a treatment, and liquid food or food simulants. The treatment reduces the diffusion of the plasticiser and the influence of some factors of this processing were investigated. A mathematical model, able to simulate these mass transfers and to quantify treatment parameters, is proposed to quantify the diffusion rate in terms of an average diffusion coefficient. 16 refs. 

Exposure to gaseous and humid environments affects mechanical properties, friction, and wear of polymers. Synergistic effects between abrasion, wear, and corrosion result in amplified damage (59, 60). The dominant and synergistic influence of some factors may be noted as follows. 

Myasnikov, A. L., 1958, Influence of some factors on development of experimental cholesterol atherosclerosis, Circulation 17 99-113. 

Kostial K, Kello D, Blanusa M, Maljkovib T, Rabar I (1979) Influence of some factors on cadmium pharmacokinetics and toxicity. Environ. Health Perspect. 28 ... 

G.S. Polunin, S. Fyodorov, and A.A. Ivanov, Influence of some factors on the sutures of lens,... 

Taking into account syndiotactic 1,2-PB microstmctures and the presence of >C=C< various bonds in the polydiene macromolecules, the influence of some factors on the polymer chemical transformations has been of interest. The factors in question are determined both by the double bond nature in the polymer and the nature of the substituent in the macromolecules. 

Tahtat D, Mahlous M, Benamer S, Nacer Khodja A, Larbi Youcef S, Hadjarab N, Mezaache W (2011) Influence of some factors affecting antibacterial activity of PVA/Chitosan based hydrogels synthesized by gamma irradiation. J Mater Sci Mater Med 22 2505... 

A complete discussion of the corrosion behavior of alloy systems and the influence of metallurgical factors on each is available (30). Some of these factors in a few technologically important alloy systems are discussed here. 

The figures given in the table are obtained on mouldings relatively free from orientation and tested under closely controlled conditions of temperature, testing rate, and humidity. Changes in these conditions or the use of additives may profoundly affect these properties. Details of the influence of these factors on mechanical properties have been published in the trade literature but Figures 18.11-18.14 have been included to illustrate some salient features. 

The structure of the cake formed and, consequently, its resistance to liquid flow depends on the properties of the solid particles and the liquid phase suspension, as well as on the conditions of filtration. Cake structure is first established by hydrodynamic factors (cake porosity, mean particle size, size distribution, and particle specific surface area and sphericity). It is also strongly influenced by some factors that can conditionally be denoted as physicochemical. These factors are ... 

In anionic and coordination polymerizations, reaction conditions can be chosen to yield polymers of specific microstructurc. However, in radical polymerization while some sensitivity to reaction conditions has been reported, the product is typically a mixture of microstructures in which 1,4-addition is favored. Substitution at the 2-position (e.g. isoprene or chloroprene - Section 4.3.2.2) favors 1,4-addition and is attributed to the influence of steric factors. The reaction temperature does not affect the ratio of 1,2 1,4-addition but does influence the configuration of the double bond formed in 1,4-addition. Lower reaction temperatures favor tram-I,4-addition (Sections 4.3.2.1 and 4.3.2.2). 

In some studies, an increase in the run-up distance with tube diameter was reported, but this may be owing to the hidden influence of such factor as tube roughness. The ratio of the run-up distance to the tube diameter Xoot/D was found to be in the range of 15 0. 

A particular problem with GRAFA and RBL is the reproducibility of the retention data. The retention time axes should be perfectly synchronized. Small shifts of one time interval (thus the ith spectrum in X, corresponds with the i+lth spectrum in X ) already introduce major errors (> 5%) when the chromatographic resolution is less than 0.6. The results of an extensive study on the influence of these factors on the accuracy of the results obtained by GRAFA and RBL have been reported in Ref. [37]. Although some practical applications have been reported [38,39], the lack of robustness of RBL and GRAFA due to artifacts mentioned above has limited their widespread application in chromatography. 

It has been found that many environmental factors influence the amount and composition of root exudates and hence the activity of rhizosphere microbial populations. Microbial composition and species richness at the soil-plant interface are related either directly or indirectly to root exudates and thus vary according to the same environmental factors that influence exudation. In es.sence, the rhizosphere can be regarded as the interaction between soil, plants and microorganisms. Figure 2 shows some of the factors associated with these interactions, which will be discussed during the course of the chapter. Here we mention briefly the influence of some plant and microbial factors on root exudation and rhizosphere microbial populations, while soil factors are discussed later. 

DE Wurster, SF Kramer. Investigation of some factors influencing percutaneous absorption. J Pharm Sci 50 288-293, 1961. 

The robustness of an analytical procedure for the determination of the analyte A in presence of some accompanying species i = B,...,N under influence of various factors fj(j = l,...,m) according to Eq. (4.30) is in reciprocal proportion to the sum of all their cross sensitivities, SA multiplied by the actual amounts, x and the specific influencing strengths, hjy of the factors multiplied by their actual values (in relation to xA) see Danzer (2004). Because of the way measurements are obtained, the range of their values is range = (0... oo), so it makes sense to calculate the relative robustness which includes the analyte sensitivity and amount itself, SAA xA, as follows ... 

Lauren D R, Jensen D J, Smith W A and Dow W (1996), Mycotoxins in New Zealand maize A study of some factors influencing contamination levels in grain , New Zealand J. Crop Hort. Sci., 24, 13-20. 

For our purposes, oaks are important because they drop the acorns that determine how many white-footed mice successfully withstand the harsh winter months. Before winter arrives, however, a multitude of other factors has influenced the number of mice available to gather the acorns. One of these factors is the mice s reproductive activity, and this happens to be under the influence of some peculiar pheromones. Because they contribute to determining the number of mice, these chemicals also enter our story. They are airborne signals present in adult-mouse urine that affect the maturation and reproductive success of young female mice. 

Although the use of enclosures is conceptually the simplest approach, some particular problems arise in their use in studies of NH3 loss. These are associated with the chemical reactivity of the gas, particularly its reactivity with water, and to the strong influence of environmental factors on the volatilization process (11). Matching conditions within the enclosure to those prevailing outside is a difficult task and much of the data obtained using enclosures is open to question. However, the problems associated with enclosures can be overcome if the air speed through the enclosure is controllable to within the same range as that of wind speed at the experimental site (9, 12). 

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