Process milestone practices

AH cephalosporins found in nature (Tables 1 and 2) have the D-a-aminoadipic acid 7-acyl side chain (21). AH of these compounds can be classified as having rather low specific activity. A substantial amount of the early work in the cephalosporin area was unsuccessfiiHy directed toward replacing the aminoadipic acid side chain or modifying it appropriately by fermentation or enzymatic processes (6,22). A milestone ia the development of cephalosporins occurred in 1960 with the discovery of a practical chemical process to remove the side chain to afford 7-ACA (1) (1). Several related processes were subsequendy developed (22,23). The ready avaHabHity of 7-ACA opened the way to thousands of new semisynthetic cephalosporins. The cephalosporin stmcture offers more opportunities for chemical modification than does that of penicillins There are two side chains that especiaHy lend themselves to chemical manipulation the 7-acylamino and 3-acetoxymethyl substituents. 

This chapter is not a systematic account of the history of electrochemistry, nor does it give detailed descriptions of all the contributions made by numerous scientists who have worked in the field. The main objective of the chapter is to outline the most important milestones in the development of electrochemistry and to show the relationship between the development of electrochemistry and other sciences. At all stages of the development of electrochemistry, an intimate connection existed between the development of theoretical concepts and the discovery of methods for a practical application of electrochemical processes and phenomena. 

From this beginning there has evolved a series of texts surpassing by far the scope and longevity envisioned by the founding Editorial Board. The McGraw-Hill Series in Chemical Engineering stands as a unique historical record of the development of chemical engineering education and practice. In the series one finds the milestones of the subject s evolution industrial chemistry, stoichiometry, unit operations and processes, thermodynamics, kinetics, and transfer operations. 

The duration of the development process, together with the progressive investments required, make it mandatory to have milestones along the way (see Table 3). At these milestones key data are reviewed and a decision taken to continue if the target profile can still be met, or to stop if this is not the case (go/no go decision). In practice the third option i.e. to adapt... 

This workshop focused on factors such as work processes, systems, and technologies that could enable and accelerate the pace of innovation and increase the yield of major innovations from work in the basic chemical sciences. More specifically, speakers identified teamwork, commitment, standardized portfolio management, clear goals, well-defined milestones, and effective technology transfer as some of the characteristics of innovative institutions and practices. Successful approaches to innovation have taken place in different environments and between different environments—despite infrastmcture and cultural differences, both interdisciplinary collaborations and collaborations between industry and academia have proven beneficial for all parties. Funding must also be available to promote innovation at stages of research often ignored. 

Membrane filters were first commerciafised in 1927 by the Sartorius Company in Germany using the Zigmondy process. Reverse osmosis (RO) was first observed and studied in the 1920s. However, it remained unnoticed until rediscovered by Reid and his co-workers 30 years later. The first practical phenomenon of haemodialysis was demonstrated by Kolff in the 1940s. Membrane milestones are given in Table 1.1. 

Several scientific milestones transformed dentistry in the nineteenth century. In 1844, Horace Wells administered nitrous oxide to a patient before a tooth extraction, becoming the first dentist to use anesthesia. In 1890, dentist Willoughby Dayton Miller connected microbes to the decay process, extending the germ theory to dental disease. In 1898, William Hunter introduced the term oral sepsis to the profession of dentistry and called attention to the contaminated practices and instruments used by dentists. In 1918, radiology was added to dental school curricula, and by the 1930 s, most dentists in the United States were using X rays as part of routine dental diagnostics. 

The life cycle of a new drug is illustrated in Figure 1. As shown, the process consists of sequential phases and milestones. The phases are defined by the stages of preclinical and clinical development leading to market launch. In practice, the development phases are rarely discrete so that only the decision points clearly mark progress. 

Despite a long history, it was not until 150 years later that gas separations using polymer membranes became a reality in the gas separation industry. Until the 1970s, the dense polymer membranes available were too thick to obtain the high permeation flux required for practical applications. The development of the Loeb-Sourirajan process for making defect-free, high-flux, ultrathin asymmetric membranes for RO was a milestone in membrane history (Loeb and Sourirajan, 1963). Since that time, many polymer membranes based upon asymmetric membranes and their modules have been developed and evaluated in pilot-scale for MF, UF, and RO applications (Baker, 2000). 

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