Resource mass intensity

In the discussions around E factor/mass intensity and solvent selection, we have considered metrics that begin to address Green Chemistry Principle 1 (prevention) and 5 (use safer solvents). Green Chemistry Principle 7 considers the use of renewable resources. 

One approach to addressing the measurement of the use of renewable resources would be to develop mass metrics that record the amount or proportion of renewable resources used in a process, for example, a renewables intensity analogous to mass intensity. 

There are more indicators (e.g., mass intensity, MI, and mass productivity) that belong to this general class of resource intensity indicators, for example, which quantify greermess of chemical processes and products in terms of effectiveness of mass and energy intensity. 

The results obtained for the sixteen combinations are summarized in Table 2.10. The unit energy cost was used to assess economic performance. A mass intensity index (Mil), defined as [(mass of feedstock-mass of bioethanol produced)/mass of bioethanol produced], and a water intensity index (WII), defined as (mass of fresh water/mass of ethanol produced) (El-Halwagi, 2012), were calculated. These two indices show the efficient use of basic resources, feedstocks and water. The ethanol composition after conversion is also reported. It can be observed that the best values for the WII are associated to... 

An alternative approach for the utilization of biomass resources for energy applications is the production of dean-buming liquid fuels. In this respect, current technologies to produce liquid fuels from biomass are typically multi-step and energy-intensive processes. Aqueous phase reforming of sorbitol can be tailored to produce selectively a clean stream of heavier alkanes consisting primarily of butane, pentane and hexane. The conversion of sorbitol to alkanes plus CO2 and water is an exothermic process that retains approximately 95% of the heating value and only 30% of the mass of the biomass-derived reactant [278]. 

The first major task faced by planners is to assess the current state of the EHS system. Significant variability exists in the components of the EHS system. Planners must know the exact capabilities of each component. For the EMS dispatch system, how is dispatch performed and how can it be used to make triage decisions For EMS, how many ambulances and EMS providers exist How many can be requested from surrounding regions How are the destinations of EMS patients determined For EDs, how many can handle major trauma Minor trauma Intensive care patients How can a massive influx of patients be handled What alternate sites for care exist What transportation resources are available for distributing treated patients efficiently to maintain ED inflow and outflow What alternate shelter sources exist What preparations for mass decontamination are in place This survey must be continually repeated to ensure that the latest data are available to planners. 

By brainstorming about potential disaster scenarios and the scope of resources anticipated to be needed under each scenario, the intensity and duration of the mental health response can also be anticipated. The U.S. Department of Health and Human Services (2004) has developed a population exposure model that planners can use to estimate the psychological impact of mass violence and terrorism and, therefore, the resources that might he needed. The model s underlying principle is that individuals who are most personally, physically, and psychologically exposed to trauma and the disaster scene are likely to he affected the most (Figure 5.1). 

Clearly, in a large outbreak, the demand for mechanical ventilation, intensive care unit beds, and skilled personnel could overwhelm available resources. Chapter 6 will discuss the role that physicians can play in addressing the skilled workforce needs during a mass disaster. 

Vertical closed-cycle helium turbomachinery may be developed and deployed before horizontal helium turbomachinery, because the first application of a closed helium cycle will most likely be to direct-cycle power conversion for gas-cooled reactors (potentially the NGNP). Thus, at the time of deployment of the MCGC, engineering design and manufacturing capabilities are likely to be further advanced for vertical machinery than for horizontal. As with aeroturbines, there exist strong drivers to reduce the mass of vertical helium turbomachinery that have the potential to ultimately make vertical machinery less expensive and resource-intensive than horizontal machinery. 

How much sample can be conveniently prepared for counting This may depend upon economics as much as laboratory resources. A sample may need to be dried, ashed and ground to a small particle size. Can such extra labour intensive activity be justified In a commercial situation, would the client be prepared to pay for it What limit of detection is being aimed for This will be related to sample mass and count period, as we know from Equation (13.1). 

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