NEAR event

As part of their BBS program, many companies use an Observed Hazard card (also called a NEAR Event or STOP card). An example is shown in Figure 3.6. The card is used to record observations of hazardous situations. If the employee considers the observed situation to present an immediate danger he or she has the authority to stop the work until a review has been carried out. 

During the first phasis until 20 bars, the acoustic emission is mainly located in the bottom of the vessel near the defect. The amplitude of the events is very high (between 60 dB and 90 dB). 

No emission during holds was observed but the concentration of events in clusters and the high level of amplitude of events confirmed the results of the proof test. After 20 bars, the bottom of the vessel around the defect became silent and activity is observed in the high part of the vessel near welds. 

Sonochemistry can be roughly divided into categories based on the nature of the cavitation event homogeneous sonochemistry of hquids, heterogeneous sonochemistry of hquid—hquid or hquid—sohd systems, and sonocatalysis (which overlaps the first two) (12—15). In some cases, ultrasonic irradiation can increase reactivity by nearly a million-fold (16). Because cavitation can only occur in hquids, chemical reactions are not generaUy seen in the ultrasonic irradiation of sohds or sohd-gas systems. 

The following cautions should be observed Do not destroy or remove inhibitor. Do not contaminate with alkaline or strongly acidic materials. Do not store in the presence of a water layer. In the event of spillage or misuse that cause a release of product vapor to the atmosphere, thoroughly ventilate the area, especially near floor levels where vapors will collect. 

Because the cytotoxic effects of the energetic lithium-7 and alpha particles are spaciaHy limited to a range of only about one-ceU diameter, the destmctive effects are confined to only one or two cells near the site of the event. Thus BNCT involves the selective deUvery of sufficiendy high concentrations of B-containing compounds to tumor sites followed by the irradiation of these sites with a beam of relatively nondestmctive thermal neutrons. The resulting cytotoxic reaction can then in theory destroy the tumor cells that are intimately associated with B target. 

Precise kinetic electroanalytical data permit to describe quantitatively the kinetics of the whole process with a precision that has never been achieved before by patch-clamp techniques or spectroscopic near-field methods. This enables to investigate finely these events and to identify the exact physicochemical nature of all the individual physicochemical and biological factors which concur to produce vesicular release. 

There are two main sources of Rn to the ocean (1) the decay of sediment-bound "Ra and (2) decay of dissolved "Ra in a water column. Radon can enter the sediment porewater through alpha recoil during decay events. Since radon is chemically inert, it readily diffuses from bottom sediments into overlying waters. The diffusion of radon from sediments to the water column gives rise to the disequilibrium (excess Rn) observed in near-bottom waters. Radon is also continuously being produced in the water column through the decay of dissolved or particulate "Ra. 

The events are so fine-tuned and the size of chamber, pressure of gas, travel, distance of the moving contact and the size of blast nozzle so designed and adjusted that a near-slrike-free interruption can be achieved for low reactive currents (inductive or capacitive) as well as fullload and very heavy fault currents. The advance compression of gas through the movement of main contact plays an important role by storing a part of the gas even before opening of the arcing contacts. 

There are several widely used approaches for developing perspective about the significance of absolute risk estimates (Figure 16). The first approach is to compare the risk estimates to historical experience within your company, looking for similar events. Most companies have safety and loss recordkeeping programs that date back many years. But if directly related data are sparse, you may widen your comparison to extrapolate from near-miss incidents that could have caused the event of interest. You will not, however, frequently find solace from the company data—or even comparable industry data. 

Prompt instrumentation is usually intended to measure quantities while uniaxial strain conditions still prevail, i.e., before the arrival of any lateral edge effects. The quantities of interest are nearly always the shock velocity or stress wave velocity, the material (particle) velocity behind the shock or throughout the wave, and the pressure behind the shock or throughout the wave. Knowledge of any two of these quantities allows one to calculate the pressure-volume-energy path followed by the specimen material during the experimental event, i.e., it provides basic information about the material s equation of state (EOS). Time-resolved temperature measurements can further define the equation-of-state characteristics. 

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