Cost and Availability

Scaling up of the processes to large surface areas (i.e. to obtain asymmetric membrane systems with several layers) as is necessary for large-scale operations has been successfully demonstrated for micro/ultrafiltration and bioseparation processes, but not for other applications such as gas/vapour separation and membrane reactors, for which only small-scale laboratory equipment is available. 

The cost of inorganic membranes per unit area is reported to be much higher than for organic membranes. As argued by, e.g.. Fain [10], it is not appropriate to price organic membranes by the unit area. To be comparable with polymer membranes the module cost should be reduced by an estimated factor of about three. This factor can be lower for complete installations. Nevertheless ceramic membrane systems will always be more expensive than polymer-based ones. 

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Efficiency of transport (railways, waterways, highways) Availability and cost of export financing, insurance... 

Traditionally, active carbons are made in particulate form, either as powders (particle size < 100 pm, with an average diameter of -20 pm) or granules (particle size in the range 100 pm to several mm). The main precursor materials for particulate active carbons, PAC, are wood, coal, lignite, nutshells especially from coconuts, and peat. In 1985, 360 kt of such precursors (including 36 % wood and 28 % coal) were used to make active carbons [10], of which nearly 80 % were used in liquid-phase applications, with the rest being used in gas-phase applications. Important factors in the selection of a precursor material for an active carbon include availability and cost, carbon yield and inorganic (mainly mineral) matter content, and ease of activation. 

The growth in popularity of radiation as the initiating system for grafting arises from the improvement in availability and cost of ionizing radiation. This is due to the introduction of more powerful nuclear reactors. Apart from its inexpensiveness, radiation is a very convenient method for graft initiation because it allows a considerable degree of control to be exercised over such structural... 

The inhibitors must be readily available, and cost effective. 

Associated with factor costs are linkages with material suppliers, subcontractors and support services (e.g. temporary staffing agencies, travel agents, reference libraries, and office maintenance services). The availability and cost of these factors need to be considered. 

Fumaric acid is used in the plastics industry, in the food industry and as a source of malic add. Although demand has increased rapidly over the last 30 years its production from fermentation has been totally replaced by a chemical method. It is now produced far more cheaply by the catalytic oxidation of hydrocarbons, particularly benzene. With the continuing uncertainties concerning the availability and cost of petroleum, however, fermentation may yet be a viable alternative. 

LiCo02 is used in most of the Li batteries in production, in spite of its limited availability and cost. It gives the highest capacity and cycle numbers. Lithiated Ni oxide is next in capacity and... 

Antiemetics can be administered either intravenously or orally in this situation, depending on patient characteristics such as ability to take oral medications, dosage form availability, and cost considerations.5,10 The intravenous and oral routes are equally effective. When used at equipotent doses, the 5-HT3 antagonists have similar efficacy in preventing acute CINV, despite pharmacokinetic and receptor binding affinity differences.5,10,36... 

Pharmacists are also responsible for compounding special ear preparations for pets that are not commercially available. Sometimes the availability and cost of certain medications are prohibitive for a veterinarian s private pharmacy. 

Model selection, application and validation are issues of major concern in mathematical soil and groundwater quality modeling. For the model selection, issues of importance are the features (physics, chemistry) of the model its temporal (steady state, dynamic) and spatial (e.g., compartmental approach resolution) the model input data requirements the mathematical techniques employed (finite difference, analytic) monitoring data availability and cost (professional time, computer time). For the model application, issues of importance are the availability of realistic input data (e.g., field hydraulic conductivity, adsorption coefficient) and the existence of monitoring data to verify model predictions. Some of these issues are briefly discussed below. 

Thickening agents can be of natural or synthetic origin. Various natural gums and starches have been used traditionally in many printing styles. The materials from which they are extracted are valuable sources of foodstuffs, so availability and cost can depend on fluctuating demand from the food industry. The properties required of an ideal thickener can be summarised as follows [352] ... 

The oils from which factices are manufactured are unsaturated vegetable and animal oils, which react with sulphur. Fatty oils with iodine number greater than 80 (iodine number is defined as the number of grammes of iodine absorbed by 100 g of fat/oil) are generally used, i.e., oils with three or more double bonds per triglyceride molecule. Rapeseed oil is the most common oil used for general purpose grades and castor oil is used for oil resistant factice. Other oils are used in preference by other countries due to local availability and cost. 

The availability and costs of the four constituents are given in the following table ... 

Details of many synthetic processes are never reported and, hence, as noticed by Pletcher and Walsh [10], any contribution of electrosynthesis remains speculative. Crucial factors are generally the availability and costs of the starting materials, the material yield, a simple product isolation, the stability of the electrolysis medium and acceptable current densities. 

Since that time an enormous number of surfactants covering a wide range of chemical and physicochemical properties have been developed for quite universal as well as specific tasks in domestic and industrial applications. The criteria for selection of a surfactant for industrial production is directly connected with the feasibility of large-scale production. This is determined by several factors including availability and costs of raw materials, cost of manufacture, and performance of the finished products. In addition to these aspects, environmental considerations likewise play an increasingly important role. 

In principle, any catalyst developed in the laboratory can be manufactured in large scale. In practice, however, the necessary investments, which may include development of the production process, and die operating costs of the catalyst production plant including availability and cost of raw materials, plant maintenance, labour etc. may not be justified by the market potential. In the VK69 case, production in the existing plant according to the route in Fig. 8 was preferred but not a strict requirement. 

Notes on the application of the metals of the 8th, 9th and 10th groups and their alloys. On the basis of their properties and also of their availability and cost, quite different applications have been considered for the two metal families we are describing. 

As profiling plays a key role in lead selection and optimization, data quality, availability, and cost become important considerations. Indeed, all profiling data are critical since these will both support the selection of the best candidates and will be included in a corporate database to support further improvement of the discovery process. 

One of the most important electrolytic processes is the extraction of aluminum from an ore called bauxite. This ore is mainly composed of hydrated aluminum oxide, AI2O3 XH2O. (The x in the formula indicates that the number of water molecules per formula unit is variable.) In industry, the scale of production of metals is huge. The electrolytic production of aluminum is over two million tonnes per year in Canada alone. As you know from Faraday s law, the amount of a metal produced by electrolysis is directly proportional to the quantity of electricity used. Therefore, the industrial extraction of aluminum and other metals by electrolysis requires vast quantities of electricity. The availability and cost of electricity greatly influence the location of industrial plants. 

Risk means the agency considers only risk information when reaching decisions. Balancing means that both risks and benefits are considered. Technical feasibility means that the law requires the agency not only to consider risks, but also the availability and costs of technology to control risk. Some laws invoke more than one model. 

Further studies are needed to determine availability and costs of producing large quantities of enzyme for field use. 

This paper is concerned with the potential for production of liquid fuels from biomass in Canada. To this end, the availability and cost of wood wastes, surplus roundwood, bush residues, energy plantation trees, and municipal solid wastes (mostly cellulosic) are assessed and promising thermal, chemical and biochemical conversion processes reviewed. 

The potential of biomass to substitute for petroleum is examined in terms of resource availability and cost, conversion technology, and conversion and end-use costs. The most energy-efficient and least costly mode of utilization of wood is direct burning, followed by gasification, and, last, liquefaction. 

Hart, R.G. "Sources, Availability and Costs of Future Energy" AECL-5816, 1977... 

Potassium sulfate is produced by various methods, selection of process depending on availability and cost of raw materials. 

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