Radioactive and chemical

FIRAC is a computer code designed to estimate radioactive and chemical source-terms as.sociaied with a fire and predict fire-induced flows and thermal and material transport within facilities, especially transport through a ventilation system. It includes a fire compartment module based on the FIRIN computer code, which calculates fuel mass loss rates and energy generation rates within the fire compartment. A second fire module, FIRAC2, based on the CFAST computer code, is in the code to model fire growth and smoke transport in multicompartment stmetures. 

The Contribution of Radioactive and Chemical Dating to the Understanding of the Environmental... 

Radioactive and chemical dating methods are yielding most valuable information on the history of the earth and the planetary system. In this paper mainly methods using cosmic ray produced isotopes are discussed. 

Second, waste that contains hazardous substances is classified based on considerations of health risks to the public that arise from waste disposal. The existing classification systems for radioactive and chemical wastes in the United States are not based primarily on considerations of health risks to the public. Rather, classification of hazardous wastes has been based primarily on the source of the waste or the presence of particular hazardous substances. The absence of risk-based waste classifications has had a number of undesirable ramifications ... 

The primary purpose of this Report is to present NCRP s recommendations on classification of hazardous wastes. The Report is directed at a multidisciplinary audience with different levels of technical understanding in the fields of radiation and chemical risk assessment and radioactive and chemical waste management. Anew hazardous waste classification system is proposed that differs from the existing classification systems for radioactive and hazardous chemical wastes in two fundamental respects. First, hazardous waste would be classified based on considerations of health risks to the public that arise from disposal of waste. Hazardous waste would not be classified based, for example, on its source. Second, the classification system would apply to any hazardous waste, and separate classification systems for radioactive and hazardous chemical wastes would not be retained. In the proposed system, waste would be classified based only on its properties, and the same rules would apply in classifying all hazardous wastes. 

The term risk as used in this Report refers to the probability of harm, combined with the potential severity of that harm. In the context of impacts on human health resulting from disposal of hazardous waste, risk is the probability of a response in an individual or the frequency of a response in a population taking into account (1) the probability of occurrence of processes and events that could result in release of hazardous substances to the environment and the magnitude of such releases, (2) the probability that individuals or populations would be exposed to the hazardous substances released to the environment and the magnitude of such exposures, and (3) the probability that an exposure would produce a response. For example, risk refers to the probability that a member of the public living near a waste disposal site will develop a certain type of cancer as a result of emplacement of hazardous substances at the site. When expressed as a probability, risk is a number between zero and one, without units. In this Report, all values are risks to an individual over a normal lifetime. Risk can be calculated for individual radioactive and chemical substances in waste and for specific pathways by which release and exposure might occur. These component risks can be combined to yield an overall risk that arises from disposal of waste. 

Return all radioactive and chemical materials to their place of storage. This may simply mean returning the radioactive materials to the laboratory instructor and the chemicals to their storage cabinets. 

The AP test requires you to know about nuclear equations, half-lives, radioactivity, and chemical applications of nuclear properties. This chapter begins with a brief review of the history of the nucleus and how we came to know about it and then moves into the required topics. 

Permissible Releases of Radioactive and Chemical Substances to the Atmosphere (1985), Energoatomizdat Publishers, Moscow (in Russian). 

In an attempt to deal with such unwanted substances as radioactive and chemical wastes, disposal sites are often used that are hydraulically connected with usable water supplies via subsurface transport routes. To manage these wastes effectively, it is desirable to have the capability of predicting the course of solute transport along these connecting routes. 

Discuss factors governing the attainment of radioactive and chemical equilibrium in a water-rock system. What chemical and physical processes aid or hinder the attainment of radioactive (secular) equilibrium in a groundwater ... 

Transmutation is a treatment that converts molecules with a long half-life into molecules with shorter half-lives (making required storage times shorter). This process could be used with spent nuclear fuel, to permit some re-use of material. However, such recycling produces additional radioactive and chemical wastes, as well as creating short-term handling hazards. Further, it is considerably cheaper to mine and process uranium ore than it is to re-process wastes. 

Mixed waste contains both radioactive and chemically hazardous materials such as toxic, corrosive, flammable, or explosive materials. The radioactive component may be either HLW or LLW. All liquid HLW is mixed waste, usually in the presence of organic solvents or heavy metals in addition to radioactive components. Disposal of mixed wastes is regulated by the EPA under the Resource Conservation and... 

Documentation associated with HCF waste management activities and maintained in the HCF Facility includes Chemical Waste Disposal Requests, Radioactive/Mixed Waste Disposal Requests, Radioactive Waste Traveler Forms, Radioactive and Chemical Waste Addition Logs, and storage-facility periodic inspection checklists. The respective waste management group within the ES H Center, as described below, maintains the original disposal requests. 

The most extensive use of RIA has been in the clinical laboratory for the diagnosis of metabolic malfunction and disease and for the management of therapy. For clinical applications an RIA must meet certain requirements. Accuracy, for example, should normally be +/- 10% or better. Owing to the great number of assays that must be performed, simplicity of methodology and economy are important considerations. It is desirable to use the same tube for both the reaction and for counting to reduce cost and to reduce the number of necessary operations. The use of small tubes and vials helps achieve an economic utilization of reagents and, in the case of liquid scintillator, also helps to reduce the problem of radioactive and chemically hazardous waste. 

The second task is the one most frequently met in monitoring work. It can be solved in many different ways, but basically there are two typical approaches (1) To add inactive carrier in known amounts, allow for isotope exchange, separate, and purify until further purification does not influence the characteristics of the radiation, and measure the radioactivity and chemical yield the measurement of radioactivity in this case need not be discriminatory. (2) Without chemical pretreatment, to measure the intensity at one energy only (if no other radionuclides emitting at the same energy are present) or to use the difference in half-lives to differentiate between two (or more) radionuclides, as shown in Figure 3. 

Soviet investment in chemical warfare expanded considerably in the post-war period. The Military Chemical Forces (VKhV) are a separate arm of the military establishment. Commanded by a three-star general (Colonel-General V. K. Pikalov), these specialist troops consist of units and subunits with responsibilities for chemical defence, radiation and chemical reconnaissance, the operation of flame throwers and smoke generators, the identification of enemy chemical weapon sites and other targets for Soviet chemical strikes, and for the decontamination and deactivation of personnel, weapons, equipment, structures and terrain exposed to radioactive and chemical agents. Apart from the employment of smoke and flame equipment, these chemical troops are trained and equipped for defensive purposes they are not responsible for the delivery of chemical munitions. ... 

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