Development cycle/process, components

Advancement in the use of process analytical tools prior to process scale-up affords opportunities to reduce product development cycles by having an earlier understanding of the parameters that influence a product s processability, as well as properties that impact the final quality. Implementation in the development phase of a product will reduce the dependence on empirical approaches to product formulation. Thorough understanding of quality attributes in a formulation or process allow one to tailor-make a product through its processing and formulation by relating properties that are important to the final product quality to the chemical and physico-chemical characteristics of the components. 

At CEA, the studies on this process have started more recently. The two critical components of the process components are the high-temperature decomposition reactor and the SDE. Beside the European project mentioned above on the process heat reactor for S03 decomposition, CEA studies therefore focus on the electrolysis section, with a pilot now in operation in Marcoule (see Figure 7). Indeed, a major challenge for the HyS process is the development of an efficient, cost-effective SDE. Prevention of S02 migration through the separation membrane of the electrolyser, which leads to undesired sulphur deposits, remains a major technical hurdle to overcome. Like for all electrolytic processes, economic competitiveness of the cycle will also depend on the minimisation of electrolysis overvoltage and on components lifetime (membrane, interconnectors). 

A special focus of the development regarding solar thermochemical processes is the high temperature endothermic decomposition of sulphuric acid. The solarisation of this step was part of the R D activities of the European project HYTHEC (HYdrogen THErmochemical Cycles) with an emphasis on components development and process improvement (Noglik, 2009). 

A system is typically composed of related elements (subsystems and components) and their interfaces. Additionally, elements include the people required to develop, produce, test, distribute, operate, support, or dispose of the element s products, or to train those people to accomplish their role within the system. Figure 1 provides a hierarchy of names for the elements making up a system. This generic system hierarchy is a key concept within this standard because it ties the system architectures, specificahon and drawing trees, system breakdown structure (SBS), technical reviews, and configuration baselines together. Many elements within the system hierarchy can be considered a system by the classical definition, but actually represent subsystems within the system hierarchy. Likewise, the life cycle processes represent subsystems within the overall system hierarchy. 

Complex components represent system elements that are composed of hardware, software, and/or humans, which are recognizable in terms of life cycle process (how to design, test, produce, support, etc., is known), and the domain-specific engineering team assumes responsibility for the development of the complex... 

Although development of life cycle process definitions may not be initiated prior to when the product (system product, subsystem assembly, or component snbassembly) for which it is intended to snpport is defined, the enterprise shall schedule applicable downstream life cycle processes to be available at the time needed to... 

The enterprise should initiate development of applicable downstream life cycle processes for development, production, test, distribution, support, training, and disposal to provide life cycle support to products and their subsystems, and for assemblies and their components. If system elements are being procured from suppliers or subcontractors, then consideration for life cycle support of the system elements should be addressed. Each life cycle process goes through the same development events and activities as described for products in 5.1 through 5.5, including technical reviews. 

Accelerated life tests usually take too long to be conducted online, as part of any product development cycle. Therefore, they must be conducted offline, well before the components, materials, or processes are needed for a given application. For these reasons, ALT is usually conducted genetically, using generic samples which represent the materials, components, and processes used for a variety of products [100]. 

As shown in Fig. 24, the mechanism of the instability is elucidated as follows At the portion where dissolution is accidentally accelerated and is accompanied by an increase in the concentration of dissolved metal ions, pit formation proceeds. If the specific adsorption is strong, the electric potential at the OHP of the recessed part decreases. Because of the local equilibrium of reaction, the fluctuation of the electrochemical potential must be kept at zero. As a result, the concentration component of the fluctuation must increase to compensate for the decrease in the potential component. This means that local dissolution is promoted more at the recessed portion. Thus these processes form a kind of positive feedback cycle. After several cycles, pits develop on the surface macroscopically through initial fluctuations. 

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