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Formulation and Structure

Polymer structure and formulation. As an example, Woo et al. [7] measured OIT values for series of commercial PVC resins and polyester thermoplastic elastomers (TPEs). The researchers used the ASTM D3895-80 procedure, but substituted air as the oxidising gas instead of pure oxygen. A dependency on thermal processing history of the TPE film samples appeared to influence the measured OIT in the PVC study, chemically different chain ends affected polymer stability and hence OIT values. [Pg.391]

Lee ER, Marshall J, Siegel CS, et al. Detailed analysis of structures and formulations of cationic lipids for efficient gene transfer to the lung. Hum Gene Ther 1996 7(14) 1701-1717. [Pg.271]

Zhu L, Lu Y, Miller DD et al (2008) Structural and formulation factors influencing pyridi-nium lipid-based gene transfer. Bioconjug Chem 19 2499-2512... [Pg.89]

Lipid. Lipids or surfactants had been used widely in the delivery of pharmacologically active materials in the form of liposomes, emulsions, or micelles. Since the first description of their potential for exogenous gene transfer, much progress has been made in the development of improved cationic lipid structures and formulations with enhanced gene transfection activity. [Pg.322]

Johnson FA, Craig DQM, Mercer AD, Chauhan S. The effects of alginate molecular structure and formulation variables on the physical characteristics of alginate raft systems. Int ] Pharm 1997 159 35 2. [Pg.599]

Among other subjects the influence of the conditions, in which the polymerization process is conducted, on the supramolecular structure of the polymer formed is discussed in studies40-42. Using these data the researchers analyzed the impact of polymerization kinetics on the polymers supramolecular structure and formulated the basic principles for controlling the structure of the polymer in the course of its synthesis. They also proposed a new thermodynamic approach for controlling supramolecular structures. The possible uses of this method are demonstrated in the polymerization of trioxane and triethylamine in different solvents and at different monomer concentrations. The purpose of this approach and the manner in which it differs from the conventional kinetic approach are roughly illustrated by the scheme in Fig. 5. [Pg.107]

An MEA performance of -600 mV at 400 mA/ cm under realistic system operating conditions has been demonstrated, representing a major milestone towards developing a viable atmospheric PEMFC system. To further enhance cell performance (to desired operating conditions of 0.8 V at 400 mA/ cm ), optimization of cathode structure and formulation to enhance proton conduction and cathode catalyst utilization is required. [Pg.299]

Most of the drugs on the market are obtained as a defined crystalline structure and formulated as solid dosage forms. It is well known that a molecule ean erystallize to give different crystalline structures displaying what is called polymorphism. The erystal structures may be anhydrous or may contain a stoichiometric number of solvent moleeules leading to the formation of solvates (hydrates in case of water molecules). Pseudopolymorphism is the term used to describe this phenomenon. [Pg.986]

The oxidation of high energy irradiated polymers progresses in relation with their basic component structure and formulation, which is initiated by the scission of backbones. The activation energy (Ea) required for oxidative degradation is the key of stability evaluation. The values of activation energies are placed on the range between 100 and 120 kJ moF for different classes of insulation materials (polyethylene, ethylene-propylene copolymer, poly(vinyl chloride) used in the manufactures of cables for nuclear power plants [176]. The life time allows the prediction... [Pg.142]

The target analysis aims on the one hand to systematically structure and formulate targets within a project and on the other hand to record them in a binding manner. [Pg.290]

Now that we have discussed the relationships between rheological properties and PSA performance, we will eonsider the control of the rheological properties through polymer structure and formulation. An excellent detailed review of many of these issues can be found in an article by Creton [34]. [Pg.526]

The methods for solving an optimization task depend on the problem classification. Since the maximum of a function / is the minimum of the function —/, it suffices to deal with minimization. The optimization problem is classified according to the type of independent variables involved (real, integer, mixed), the number of variables (one, few, many), the functional characteristics (linear, least squares, nonlinear, nondifferentiable, separable, etc.), and the problem. statement (unconstrained, subject to equality constraints, subject to simple bounds, linearly constrained, nonlinearly constrained, etc.). For each category, suitable algorithms exist that exploit the problem s structure and formulation. [Pg.1143]

C for about 1 h. Poly benzimidazole adhesives have a higher temperature ceiling than polyimide formulations but are markedly susceptible to oxidative degradation above 260 °C. The relationships between low-temperature performance and the structure and formulation of the adhesive have also been considered [78,79], and the polyurethane adhesives are particularly good at very low test temperatures. [Pg.231]

NO is very reactive towards copper ions, both Cu(I) and Cu(II). Until very recently only two copper nitrosyl X-ray structures were known, one possessing a bridging Cu"-rNO)-Cu" structure and formulation [v(N-O) = 1460 cm ] [78], the other being a mononuclear copper-nitrosyl complex [(Tp )Cu(NO)j (R= Bu, R = H) ... [Pg.51]

Increasing the conversion, the HAL selectivity increases slightly, passes through a maximum and then drops for conversions between 90 and 95%. In parallel, some heavy products, among which acetals have been recognized, are formed. If the formation of these by-products is catalytical or not is not known, but it is interesting to see that presence of a larger Ni area or the presence of Na in the cat alyst) seems to limit their formation. Further work is needed to try to correlate catalyst structure and formulation with the forrn tion of these heavy compounds. [Pg.132]

The use of CuAAC reaction in polymer science has clearly provided very rich dividends both in terms of creating very novel structures and formulating innovative strategies to improve the synthesis of previously studied systems. [Pg.251]


See other pages where Formulation and Structure is mentioned: [Pg.244]    [Pg.350]    [Pg.301]    [Pg.642]    [Pg.537]    [Pg.26]    [Pg.128]    [Pg.646]    [Pg.729]    [Pg.19]    [Pg.526]    [Pg.118]    [Pg.112]   


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Structural formulations

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