Exceptional operating circumstances

Two other deposition mechanisms, in addition to the six listed, may be in operation under particular circumstances. Some dust particles may be collected on filters by sieving when the pore diameter is less than the particle diameter. Except in small membrane filters, the sieving mechanism is probably limited to surface-type filters, in which a layer of collected dust is itself the principal filter medium. 

Other artifacts that have been mentioned arise from the sensitivity of STM to local electronic structure, and the sensitivity of SFM to the rigidity of the sample s surface. Regions of variable conductivity will be convolved with topographic features in STM, and soft surfaces can deform under the pressure of the SFM tip. The latter can be addressed by operating SFM in the attractive mode, at some sacrifice in the lateral resolution. A limitation of both techniques is their inability to distinguish among atomic species, except in a limited number of circumstances with STM microscopy. 

However, any given column operated at a specific flow rate will exhibit a range of efficiencies depending on the nature and capacity ratio of the solute that is chosen for efficiency measurement. Consequently, under exceptional circumstances, the predicted conditions for the separation of the critical pair may not be suitable for another pair, and the complete resolution of all solutes may still not be obtained. 

To ensure that plant is not subject to breakdown, it is important that there are no unnecessary failures to safety , that is, that correctly operating safety equipment only operates because of exceptional circumstances, not avoidable faults. Safety shutdown will occur for various reasons, i.e. ... 

For landfill, costs vary highly across Europe. The main reason are differences in landfill quality (a point that will be quickly become less important now that the EU Landfill directive is becoming operational) and particularly landfill tax systems. Differences between some 2 per tornie in some EU countries (for inert waste) and up to 280 per tonne in, e.g., some places in Germany, may occur (though the latter value must be regarded as exceptionally high). Technically, even in countries with unfavourable circumstances like the... 

Until U.S. EPA calls in the facility s Part B permit application, where precise permit conditions will be established through a trial burn, owners/operators of interim status BIFs must ensure compliance with emission standards by showing certification of precompliance and certification of compliance. As the deadlines for these certifications have already passed, all interim status BIFs, except for possible extenuating circumstances, should be in the compliance stage. 

Over and above this, and particularly for the larger types with long rotor blades, airing the pump to atmospheric pressure while the impellers are rotating may be done only when observing exactly the rules given in the operating instructions. Under certain circumstances it is possible to operate turbomolecular pumps under exceptional conditions. 

However, it should be pointed out that any given column, operated at a specific flow rate, can exhibit a range of efficiencies depending on the nature of the solute that is chosen for efficiency measurement. Consequently, under exceptional circumstances, the predicted conditions for the separation of the critical pair may not be suitable for another pair and the complete resolution of all solutes may not be obtained. This could occur if the separation ratio of another solute pair, although larger, was very close to that of the critical pair but contains solutes, for example, of widely different molecular weight. However, the possibility of this situation arising, in practice, is extremely remote and will not be considered in this discussion. It follows, that the efficiency required to separate the critical pair, numerically defined, is the first performance criterion... 

Microbial products may be formed as a result of a variety of processes which occur within the cells of a microbial culture. In some cases the cell itself may be the desired product, or it may be that the product is formed as the direct consequence of its growth. There is in the latter circumstances a direct link between growth and the accumulation of product. However, there are many important microbial products which are not growth-associated, where there may exist mechanisms within the cells, as outlined in Section S.S.2, which operate to produce a particular material only under certain special circumstances. As a result, the yield coefficient Yr,s is of little value in predicting the course of product accumulation, except when the overall productivity of a complete batch operation is considered. 

Before a trial starts, a charter needs to be written and agreed upon by the trial sponsor and the committee. This charter describes the structure and operation of the committee and specifies its activities and responsibilities. The DMC should have access to fully unblinded data, with actual treatments and not just codes available for its review. Except in certain limited circumstances, trial integrity is best protected when interim data comparing treatment groups are seen only by the DMC members and statisticians preparing the interim report (Ellenberg et al., 2003, see also O Neill, 2006). 

Specifically, the rule made the sale of cigarettes and smokeless tobacco to children and adolescents, anyone younger than 18 years of age, a federal violation. In addition, the rule required manufacturers, distributors, and retailers to comply with certain conditions regarding the sale, distribution, and promotion of tobacco products. It prohibited all free samples and limits retail sales in most circumstances to face-to-face transactions. As a result, vending machines and self-service displays were prohibited, except in facilities where the retailer or operator ensures that no person younger than 18 is present or is permitted to enter at any time. 

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