CUMULATIVE natural products

While the individual property comparisons amply differentiate the natural products from combinatorial and drug libraries, the cumulative diversity can only be visualised by principal component analysis (PCA). 

FIGURE 9.10 Tree-like graphical representation of natural product scaffolds. For clarity, only scaffolds that cumulatively represent at least 0.2% of the natural products in the DNP are shown. 

Vol. 31 Studies in Natural Products Chemistry Cumulative Indices Vol. 1-30 Vol. 32 Bioactive Natural Products (Part L)... 

Natural Product Reports is a bimonthly review journal which reviews recent developments in natural product chemistry. Each issue contains approximately 90 pages covering four or five articles there is an author index and a subject index cumulated annually) to facilitate location of articles dealing with specific areas. 

Carbon 14 is produced by the intense neutron fluxes on the nitrogen in the atmosphere and the cumulative production of carbon 14 by atmospheric explosions is estimated at 6 x 10 curies, i.e. 220 years of natural production. 

Figure 3.20 shows the distribution of the EUR, i.e., cumulative production, reserves and resources of conventional natural gas for different world regions. 

The projected growth scenarios for conventional gas seem justified from the point of view of ultimately recoverable resources, and unlike for oil, no major discrepancies between projected demand and supply are to be expected in the coming decades. An important aspect of the future availability of natural gas, however, is the creation of the necessary infrastructure for the production and subsequent transport of the gas to the customer. The cumulative investments for the gas-supply infrastructure until 2030 are estimated to amount to US 3.9 trillion (IEA, 2006). 

In Chapter 18 we show that a chain of process steps, starting from natural gas, will result in the production of liquid H2 with an overall thermodynamic efficiency of 57%. Calculate the cumulative exergy consumption of this H2. 

N2 and H2 and the production of H2 from natural gas. Assume physical steps to have efficiencies of 10% and chemical steps of 60%. What is the cumulative exergy consumption of urea Separations take place with the help of compressors with an efficiency of 75%, running on electricity from an advanced natural gas-fired power station with a thermodynamic efficiency of 55%. 

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