Separation classification

Although the size separation/classification methods are adequate in some cases to produce a final saleable mineral product, in a vast majority of cases these produce Httle separation of valuable minerals from gangue. Minerals can be separated from one another based on both physical and chemical properties (Fig. 8). Physical properties utilized in concentration include specific gravity, magnetic susceptibility, electrical conductivity, color, surface reflectance, and radioactivity level. Among the chemical properties, those of particle surfaces have been exploited in physico-chemical concentration methods such as flotation and flocculation. The main objective of concentration is to separate the valuable minerals into a small, concentrated mass which can be treated further to produce final mineral products. In some cases, these methods also produce a saleable product, especially in the case of industrial minerals. 

Separate classifications exist for metal-cutting appHcations and wear parts (8). Classifications that are generally accepted by producers and users are available (9,10). 

Cannabis in large amounts has some hallucinogen-like activity. Nevertheless, the other features of this intoxication are sufficiently different to merit a separate classification for this drug. 

Separate classifications can lead to confusion and add a layer of complexity when developing ADR systems. 

In accordance with both the old and the new European classification system teratogenic effects constitute a health hazard but a separate classification for teratogenicity is not provided. Instead, teratogens are classified as developmental toxicants, with developmental toxicity falling within the hazard class of reproductive toxicity. 

Magnetic Separator Classification. Whereas a wide variety of magnetic equipment has evolved over the years, much of this equipment is specialized and has limited usage. A fundamental equipment classification can be made on the basis of feed condition. A wet condition involves the treatment of a slurry or slip a dry condition involves treatment where the particles are essentially free to move as independent particles. Both conditions depend on liberation of the magnetic particles. If liberation does not occur, the magnet traps the middling particles and reduces the concentration of... 

Over the last several decades, separate classification systems have been developed for radioactive and hazardous chemical wastes based on a variety of considerations, the most prevalent being the source of the waste. These classification systems have served their intended purpose of facilitating development of health-protective strategies for waste management and disposal reasonably well. However, they have exhibited a number of shortcomings and undesirable ramifications, which indicate that a new approach to classification of hazardous wastes would be beneficial. 

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. 

This Section summarizes the separate classification systems that have been developed for radioactive and hazardous chemical wastes. Impacts of the two classification systems on management and disposal of mixed wastes are also described. 

In addition to the effort required to develop a comprehensive and risk-based hazardous waste classification system based on NCRP s recommendations, several legal and regulatory impediments would need to be addressed. However, the resulting classification system would be more transparent and understandable than the separate classification systems for radioactive and hazardous chemical wastes... 

The waste classification system must be flexible so that it can accommodate special circumstances without need of a continuing series of separate classifications or ad hoc solutions. Common instances where flexibility is required include (1) taking the presence or absence of engineered waste forms into account, (2) providing for classification of small amounts of highly hazardous materials,... 

The hazardous waste classification system recommended by NCRP is depicted in Figure 6.1 at the beginning of Section 6. This proposal was developed with two fundamental objectives in mind. First, all wastes that contain radionuclides, hazardous chemicals, or mixtures of the two should be included in the same classification system. A comprehensive hazardous waste classification system should be developed to replace the separate, and quite different, classification systems for radioactive and hazardous chemical wastes, as well as the separate classification systems for radioactive waste that arises from operations of the nuclear fuel cycle and NARM waste. Second, all hazardous wastes should be classified based on considerations of risks to the public that arise from disposition of the material. In this Report, permanent disposal in a permitted facility for hazardous or nonhazardous waste is the assumed disposition of waste containing hazardous substances that has no further use to its present custodian. An important consequence of these two objectives is that the same rules should apply in classifying any waste that contains hazardous substances. 

Two curing agents that have found their way into many epoxy adhesive formulations are the polyamides and amidoamines. These are commonly used in the hardware store variety two-part epoxy resins that cure at room temperature. Both are reaction products of aliphatic amines, such as diethylenetriamine, and should be included under the subclassification of modified amines. However, these products have such widespread and popular use, they are addressed here as a separate classification. 

Monocyclic azines are very weak --donors and behave mainly as n-donors on interaction with electrophiles. However, 7r-donor character is significantly increased in their benzo derivatives which have higher energy HOMOs (Table 2). For example, acridine 25 forms a highly colored 1 1 molecular complex with 2,3,5,6-tetrachloro-l,4-benzoquinone (chlor-anil). Perimidine 96 is one of the strongest heterocyclic --donors and gives deeply colored molecular complexes with a variety of organic electron acceptors. This is consistent with its electron-rich structure and its separate classification. 

In the resulting score plot, the first PC discriminated between the ephrins and the Eph kinases, which is in agreement with the complementary nature of interactions between these proteins. A separate classification of the kinases and ligands clearly showed two clusters corresponding to the A and B subfamilies. Kinases with a unique biological interaction profile showed up as outliers in the score plot. 

Phenol (hydroxybenzene, 1) has a hydroxyl group attached directly to the benzene ring. Phenol is a stable enol and, although there are some obvious similarities, the hydroxyl group exhibits sufficiently different properties from an alcoholic hydroxyl group to merit a separate classification. 

The classification system has continued its growth with the years, a separate Classification Division being established in the Patent OflSce in 1898 for the administration of the work and problems pertaining to this field. The revisions and amplifications of the system have, of course, had to be accompanied by the movement of patents to their newly assigned locations. 

IgA deficiency has also been observed in 7 patients with central nervous system (CNS) disorders and in 5/7 patients with partial deletions of chromosome 18 (S26). The association with ataxia telangiectasia is not complete and probably represents a coincidence of genes, exemplified by the presence of either defect alone in relatives of propositi. It is of interest that other CNS defects are recorded with IgA deficiency, and partial deletions of chromosome 18 are also associated with mental retardation. It seems, however, that the predisposition to infection is closely correlated to IgA deficiency, so that ataxia telangiectasia per se does not justify separate classification as an antibody deficiency syndrome (SIO). 

The Committee appointed by the Society of Dyers and Colourists reported that no sharp dividing lines exist which make it possible to group the disperse dyes into separate classifications according to their dyeing behaviour. It was therefore decided that a series of tests which would give reproducible and comparable results should be recommended... 

There are several different directions in LM separation classifications according to module design configurations, according to transport mechanisms, according to applications, according to carrier type, and according to membrane support type. Below, these types of classifications are described and discussed briefly. 

Class IV HDAC 11 is most closely related to the class I family but also displays common characteristics with class II HDACs. The low overall homology to either of these classes has resulted in a separate classification. HDAC 11 is highly expressed in heart, brain, testis, muscle, and kidney cells and is predominantly located in the nucleus [28]. This deacetylase has short N- and C-terminal extensions little is known about its function. 

These complexes barely deserve a separate classification in that their chemistry is very similar to that of the simple carbonyl hydrides. All are diamagnetic and their formulation obeys the rare gas rule. Only rarely does the jr-cyclopentadienyl group play a distinctive role in the chemistry of these complexes, and for the majority of the chemistry it may be regarded as an inert ir-bonding ligand. 

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