Threshold amount

The following is the current list of DEA List I and List II chemicals. List I chemicals can only be bought or owned if one has a DEA or state permit. List II chemicals can be purchased in any amount below the given threshold. If one requires an amount of List II chemical above the threshold amount, then will need the same DEA permit for List I chemicals. 

There are three types of TAP emissions continuous, intermittent, and accidental. Both routine emissions associated with a batch process or a continuous process that is operated only occasionally can be intermittent sources. A dramatic example of an accidental emission was the release of methyl isocyanate [624-83-9] in Bhopal, India. As a result of this accident, the U.S. Congress created Tide III, a free-standing statute included in the Superfund Amendments and Reauthorization Act (SARA) of 1986. Title III provides a mechanism by which the pubHc can be informed of the existence, quantities, and releases of toxic substances, and requires the states to develop plans to respond to accidental releases of these substances. Eurther, it requires anyone releasing specific toxic chemicals above a certain threshold amount to aimuaHy submit a toxic chemical release form to EPA. At present, there are 308 specific chemicals subject to Title III regulation (37). 

Third, that virtually every cationic peptide sequence possesses some degree of antimicrobial activity in vitro suggests that this activity may be a general phenomenon associated with all peptides rather than solely to host defense peptides. Indeed, it has been demonstrated that a threshold amount of hydrophobicity and/or cationicity are sufficient to bestow antimicrobial activity within a peptide. ... 

Scale-up from grams to 100 g and more may lead to unexpected problems. Safe operations are essential to minimize risk during scale-up with scale-up there is always increased liability from accidents, including injury to personnel, loss of equipment, delay of key deliveries, damage to a company s reputation, and more. Some companies require that safety hazard assessments be completed before any process is mn in a pilot plant others require safety hazard assessments before a process is scaled up to greater than a given threshold amount. Testing for such assessments may be conducted on... 

An apparently straightforward method for the determination of number and strength of acid sites consists of the determination of the amount of base required to poison catalytic activity for a model reaction. By means of plots of activity versus amount of added base, the number of acid sites is obtained from the threshold amount of base required to remove catalytic activity acid strength is gauged from the slope of the titration curve. This method can therefore be called a catalytic titration. 

Another important interaction is that of limonin with the bitter flavanone glycoside naringin. Both of these bitter substances are present in grapefruit juice and Guadagni et al. (25) found that they interact at subthreshold levels in an additive way. Less than threshold amounts of limonin or naringin contribute to the bitterness of a mixture of the two compounds. The bitterness of the mixture can be predicted by adding the taste-unit contribution of each component (taste unit = concentration/ threshold). 

The paraffins dehydrogenation on platinum-alumina catalysts proceeds with constant rate up to some time-on-stream after which a slow deactivation of the catalysts takes place Since relative changes of the catalyst activity ( characterized by reaction rate) are proportional to relative amounts of the deposited coke it can suppose that coke formation is the main reason of deactivation. Deactivation can be related with an attainment of a threshold in coke concentration (Co) on catalysts. The threshold amounts are 1.8 wt.% for A-I, 6,8% and 2.2% for A-II and A-IXI catalysts respectively. The isobutane dehydrogenation in non-stationary region (C > Co) is described by the following kinetic equation ... 

First, it is critical to know the amount and composition of your raw materials and other substances you have on site. Do not forget your facility s maintenance area, where toxic and reportable materials are often used and stored. Most environmental laws have thresholds of regulation if you use less than the threshold amount of material, you do not fall under the regulation. 

The model in Chapter 4 had only one competitor taking up the inhibitor, but this is only a first approximation. One could justify this assumption only by showing that nothing changes if the system is modified to allow for uptake by both competitors. However, such modification complicates the analysis. Finally, could it be that a threshold amount needs to be consumed before the inhibitor is effective Adding thresholds to the model would be an interesting modeling task. 

The fact that large-modulation SRGs are formed only above a certain threshold amount of functionalization was also shown by Andruzzi et al.J for amorphous as well as LC polymers. They investigated copolymers derived from two photochromic monomers, 6-(4-oxy-4 -cyanoazobenzene)h x-l-yl methacrylate and 8-(4-oxy-4 -cyanoazobenzene)oct-l-yl methacrylate, and a nonphotochromic comonomer, (-)-menthyl methacrylate. Considerable amplitudes were obtained for all polymers with more than 30% of azofunctionalization. The maximum amplitudes were observed for copolymers possessing 75-80% of dye content, not the fully functionalized homopolymers. 

Q. If I supply a threshold amount of a List I chemical to a customer who also sells the List I chemical over threshold amounts, do my records have to have my customer s DEA registration number ... 

The threshold amount of mustard vapor required to produce a skin lesion (erythema) is a Ct of about 200 mg min/m. This varies greatly depending on a number of factors, including temperature, humidity, skin hydration, and body site. Warm, moist areas with thin skin, such as the perineum, external genitalia, axillae, antecubital fossae, and neck are much more sensitive. As stated earlier, a liquid droplet of about 10 pg will produce vesication. About 80% of this 10 pg evaporates and 10% enters the circulation, leaving about 10%, 1 pg, to cause the vesicle. Evaporation of small droplets is rapid and nearly complete in 2-3 min amounts larger than several hundred mithgrams may remain on the skin for several hours (Renshaw, 1946). 

Some examples of the influence of solid cocatalysts are shown in Table 58. A Cr/silica catalyst, activated at 800 °C, was tested in ethylene polymerization experiments in the presence of various solid adsorbents. In control polymerization runs, with only the catalyst and no cocatalyst, it was difficult to obtain measurable activity data when less than about 0.10 g of catalyst was added to the reactor. This result is a sign that even with the most diligent attention to feedstock purity, there is always a low level of background poison, which means that a threshold amount of catalyst is needed in the reactor to achieve measurable activity. 

The above equation typically holds above a certain (threshold) amount of the antioxidant. Below this amount the antioxidant is largely consumed during processing, and the residual amount, if any, does not contribute to the protection proportional to the square root of its initial amount. 

Fig. (9). Threshold amounts of some flavones and a chromone exhibiting antidote activity (paper disk method).

Compound B has a different shaped response. There is a range of dosages that result in no response or a response lower than a threshold amount consequently, there are safe dosages for compound B. 

A CSA is required for operations that involve total amounts of fissile material in excess of the threshold amount for non-aqueous forms (700 g U) where formal criticality safety evaluations and controls are required [Philbin, 1998, Criticality Safety Supplement to the SNL ES H Manual, Applicability Section]. The CSA requires that process designs incorporate a double-contingency principle so that at least two unlikely, independent, and concurrent changes in process conditions must occur before an accidental nuclear criticality is possible. Table 6.4-3 is a qualitative summary of the double contingency analysis from the CSA for isotope processing [Mitchell and Romero, 1999 (draft). Section 5]. 

In April 2007, the U.S. Department of Homeland Security (DHS) issued the Chemical Facility Anti-Terrorism Standard (CFATS). The DHS is to identify, assess, and ensnre effective security at high-risk chemical facilities. Included in this standard is the requirement for facilities handling chemicals above a threshold amount, to submit an SVA for DHS review and approval along with a Site Security Plan (SSP). An SVA evaluates risk from deliberate acts that could result in major incidents. It is performed in a systematic and methodical manner to analyze potential threats and evaluates these threats against plant vulnerabilities. From this analysis, it determines possible consequences and whether safeguards to prevent or mitigate their occurrence are recommended. See also Terrorism. 

The U.S. Department of Homeland Security regulates about 300 chemicals that could be used to make chemical agents or could be used in chemical attacks. - This program is also known as Top Screen. While the focus of the regulations is on chemical facilities, the regulations also cover academic institutions, if quantities of these chemicals reach a certain threshold amount. The focus of the regulations is to prevent the release of these chemicals in the environment, theft of these chemicals, or sabotage and contamination by these chemicals. 

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