Radioactive heavy metals

Neptunium is a silvery-white radioactive, heavy metal. Its melting point is 644°C, its boiling point is 3,902°C, and its density is 20.25g/cm. ... 

The transactinide series of elements (Z-104 to Z-113) are those elements that follow the actinide series (Z-89 to Z-103) and proceed to the superactinides, some of which are yet to be discovered. (Note Z is the symbol used to represent the atomic numbers [protons] of elements in the transactinide series, as well as of other elements.) All elements of the transactinide series are radioactive, heavy metals that are unstable, and they usually decay by spontaneous fission or alpha decay into smaller nuclei of elements with less mass. 

The hazards of dubnium are similar to all radioactive heavy metals of the transactinide series, but there is no threat to the public given that such a small amount of the element is produced and exists. 

Burned tobacco contains some 4,800 distinct chemicals in either gas or particle phases. Many of the compounds in both phases are highly reactive, poisonous, and toxic. Harmful products include oxidants and poisons produced during burning, as well as radioactivity, heavy metals, and pesticides that may have accumulated within the tobacco leaf. Sixty-nine of these substances are known to cause cancer in humans and animals, and many others are known to be strong irritants. 

Vitrification is particularly useful for remediation of soils contaminated with radioactive heavy metals. The radioactive heavy metals are encapsulated in a highly inert, nonporous matrix, which can be stored permanently in underground secured radioactive waste storage facilities currently under development in some Asian countries. Vitrification can also be used for sediments and slndge pollnted by heavy metals. 

For non-radioactive heavy metals such immobilisation may well negate or reduce the effects of chemical toxicity. However, immobilisation does not negate radiotoxic effects and, in fact, may exacerbate them by leading to alpha-particle emission within cells near chromosomal or nuclear material. In situations like these, human intervention using chelation therapy is required, the success of which involves targeting the... 

Uranium is a very toxic and radioactive heavy metal found in nuclear effluents also naturally and in uranium, coal, hydrocarbon exploitation and associated activities. It is therefore not surprising that it was the first to be historically considered for electro-membrane treatment (Davis et al, 1971 Wallace, 1967). 

Industrial refractories are by thek very nature stable materials and usually do not constitute a physiological hazard. This is not so, however, for unusual refractories that might contain heavy metals or radioactive oxides, such as thoria and urania, or to bkiders or additives that may be toxic. 

By using an anionic collector and external reflux in a combined (enriching and stripping) column of 3.8-cm (1.5-in) diameter with a feed rate of 1.63 ni/n [40 gal/(h ft )] based on column cross section, D/F was reduced to 0.00027 with C JCp for Sr below 0.001 [Shou-feld and Kibbey, Nucl. AppL, 3, 353 (1967)]. Reports of the adsubble separation of 29 heavy metals, radioactive and otheiwise, have been tabulated [Lemlich, The Adsorptive Bubble Separation Techniques, in Sabadell (ed.), Froc. Conf. Traces Heavy Met. Water, 211-223, Princeton University, 1973, EPA 902/9-74-001, U.S. EPA, Reg. 11, 1974). Some separation of N from by foam fractionation has been reported [Hitchcock, Ph.D. dissertation. University of Missouri, RoUa, 1982]. 

First of all, in the general part, the supply of herbal drugs and herbal mixtures, the indications and possible treatments, are dealt with, as well as explaining herbal preparations, how to make the lea, storage, and authentication. Short sections are devoted to the Standard Licences and the contamination of drugs (microbiological, heavy metal, fumigation, radioactive substances). 

Applicability Pozzolanic processes are suitable for high-volume, low-toxicity wastes containing radioactive materials or heavy metals with an organic content below 10 percent. 

The extensive industrial and commercial utilization of water-soluble polymers (polyelectrolytes) in water treatment has been developed based on the charge along the polymer chains and the resultant water solubility. The use of water-soluble polymers in water treatment has been investigated by several authors [5-26] in the recovery of metals radioactive isotopes, heavy metals, and harmful inorganic residues. This allows recycling water in the industrial processes and so greatly saves... 

Reduction of cnviromncntal pollution requires lower energy use and new technology to decrease emission of gases such as sulfur dioxide and carbon dioxide, and to prevent toxic fluoride, heavy metal, and radioactive wastes from discharging into the environment. 

The main drawback to nuclear power is the production of radioactive waste. Spent fuel from a nuclear reactor is considered a high-level radioactive waste, and remains radioactive for a veiy long time. Spent fuel consists of fission products from the U-235 and Pu-239 fission process, and also from unspent U-238, Pu-240, and other heavy metals produced during the fuel cycle. That is why special programs exist for the handling and disposal of nuclear waste. 

The contaminants that can be removed by flotation include conventional pollutants such as BOD, COD, total suspended solids (TSS), phosphorus, phenols, oil and grease, as well as toxic pollutants including heavy metals, toxic organics, pathogenic microorganisms, and radioactive radon 22.28,33,54,64,100-102... 

Particulates heavy metals, volatile organic compounds pesticides radioactive particles... 

The alpha particle is a helium nucleus produced from the radioactive decay of heavy metals and some nuclear reactions. Alpha decay often occurs among nuclei that have a favorable neutron/proton ratio, but contain too many nucleons for stability. The alpha particle is a massive particle consisting of an assembly of two protons and two neutrons and a resultant charge of +2. 

The alpha particle is a helium nucleus produced from the radioactive decay of heavy metals and some nuclear reactions. 

Sorption can significantly diminish the mobility of certain dissolved components in solution, especially those present in minor amounts. Sorption, for example, may retard the spread of radionuclides near a radioactive waste repository or the migration of contaminants away from a polluting landfill (see Chapters 21 and 32). In acid mine drainages, ferric oxide sorbs heavy metals from surface water, helping limit their downstream movement (see Chapter 31). A geochemical model useful in investigating such cases must provide an accurate assessment of the effects of surface reactions. 

Apatite exploration takes place in various regions of the World, and the most known are Kola Peninsula (Russia) and northwest Africa (Morocco). In both places, the apatite ores contain not only phosphorus as a main element but also many heavy metals, which are toxic for humans and animals. The given elements are F, As, Y, some rare earth species, Sr, Pb, Cd, Sn. The underground waters in these regions are enriched by F, Fi, Nb, some rare earth species with alkaline reaction that facilitates the migration of many ore elements. Some phosphorus containing ores are radioactive owing to the mixtures of uranium and thorium. 

Notable progress has been made over the past three decades in reducing some forms of marine pollution, such as oil, radioactive substances, heavy metals (with the exception of mercury), and some of the persistent organic pollutants, such as DDT and... 

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