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Heavy metals and

In general, nonconventional protein foods must be competitive with conventional plant and animal protein sources on the bases of cost delivered to the consumer, nutritional value to humans or animals, functional value in foods, sensory quality, and social and cultural acceptability. Also, requirements of regulatory agencies in different countries for freedom from toxins or toxic residues in single-cell protein products, toxic glycosides in leaf protein products, pathogenic microorganisms, heavy metals and toxins in fish protein concentrates, or inhibitory or toxic peptide components in synthetic peptides must be met before new nonconventional food or feed protein products can be marketed. [Pg.472]

Changes in fluid compositions include the reduction and removal of zinc from hydrauHc fluids. Zinc-free antiwear hydrauHc fluids, which may be ashless and free of phenol, were developed to meet wastewater treatment regulations for industrial sites by reducing the discharge of heavy metals and phenol into waterways. [Pg.267]

Chemical fertiliser is the predominant market for langbeinite. Comparatively small but increasing amounts of langbeinite are used by the animal feed ingredient industry (see Feeds and feed additives). Producers who supply this market must take special precautions to be sure that any langbeinite intended as an animal feed ingredient meets all USDA specifications for toxic heavy metals and other impurities. [Pg.532]

Misleading also is the idea that vinyl should be harmed from incinerators because it contains heavy-metal additives. This is an evolving issue. Most vinyl products do not contain heavy metals and vinyl is a small fraction in feed to incinerators. Reformulation to replace heavy metals is in progress but some use is likely to continue. Banning vinyl from incinerators does not eliminate this problem. Rather, regulations should specify that incinerator residues (ash) be disposed of appropriately. [Pg.509]

Unreacted phosgene is removed from the cmde chloroformates by vacuum stripping or gas purging. Chloroformates of lower primary alcohols are distillable however, heavy-metal contamination should be avoided. As stated earlier, chloroformates generating a stable carbonium ion on decomposition, ie, secondary or tertiary chloroformates or henzylic chloroformates, are especially unstable in the presence of heavy metals and more specifically Lewis acids and, hence, should be distilled at as low a temperature and high vacuum as possible. [Pg.40]

Some catalysts are ha2ardous materials, or they react to form ha2ardous substances. For example, catalysts used for hydrogenation of carbon monoxide form volatile metal carbonyl compounds such as nickel carbonyl, which are highly toxic. Many catalysts contain heavy metals and other ha2ardous components, and environmentally safe disposal has become an increasing concern and expense. [Pg.174]

Orga.nic Colora.nts. The importance of coal-tar colorants cannot be overemphasized. The cosmetic industry, in cooperation with the FDA, has spent a great deal of time and money in efforts to estabUsh the safety of these dyes (see Colorants for food, drugs, cosmetics, and medical devices). Contamination, especially by heavy metals, and other impurities arising from the synthesis of permitted dyes are stricdy controlled. Despite this effort, the number of usable organic dyes and of pigments derived from them has been drastically curtailed by regulatory action. [Pg.293]

Toxic heavy metals and ions, eg, Pb, Hg, Bi, Sn, Zn, Cd, Cu, and Fe, may form alloys with catalytic metals (24). Materials such as metallic lead, ziac, and arsenic react irreversibly with precious metals and make the surface unavailable for catalytic reactions. Poisoning by heavy metals ordinarily destroys the activity of a precious-metal catalyst (8). [Pg.508]

The paper describes the different chemical sensors and mathematical methods applied and presents the review of electronic tongue application for quantitative analysis (heavy metals and other impurities in river water, uranium in former mines, metal impurities in exhaust gases, ets) and for classification and taste determination of some beverages (coffee, bear, juice, wines), vegetable oil, milk, etc. [1]. [Pg.19]

Thus, it is shown, that use of ultrasonic at the stage of sample preparation or different type soils allows considerably to reduce time of extracts obtaining for determination of soil forms of heavy metals and realization of full decomposing for an estimation of the gross contents. [Pg.190]

Provide annual estimates of all point and fugitive emission sources (tons per year) of hazardous substances, volatile organic compounds (VOCs), heavy metals and fossil fuel products (for example, NOx and SOx) that are released to the environment. [Pg.169]

The treatment for zinc can be carried out with normal coagulants until it has formed tiny complex (chemical compound). Other heavy metals and cyanide constituents, however, will require special iittention. [Pg.417]

How is that knowledge used to find the phase of the contribution from the protein in the absence of the heavy-metal atoms We know the phase and amplitude of the heavy metals and the amplitude of the protein alone. In addition, we know the amplitude of protein plus heavy metals (i.e., protein heavy-metal complex) thus we know one phase and three amplitudes. From this we can calculate whether the interference of the x-rays scattered by the heavy metals and protein is constructive or destructive (Figure 18.10). The extent of positive or negative interference plus knowledge of the phase of the heavy metal together give an estimate of the phase of the protein. [Pg.380]

The ecological advantages of ICPs have made them of particular interest in the field of rechargeable batteries, since they do not involve heavy metals and do not appear to have any serious toxicological problems. [Pg.889]

Ammonia can also react violently with a large selection of chemicals including ethylene oxide, halogens, heavy metals, and oxidants such as chromium trioxide, dichlorine oxide, dinitrogen tetroxide, hydrogen peroxide, nitric acid, liquid oxygen, and potassium chlorate. [Pg.276]

Chemical Reactivity - Reactivity with Water Reacts slowly with water at room temperature to form limewater and oxygen gas Reactivity with Common Materials Heavy metals and dirt can accelerate decomposition to lime and oxygen. The reaction is not explosive Stability During Transport Stable Neutralizing Agents for Acids and Caustics Flush with water Polymerization Not pertinent Inhibitor of Polymerization Not pertinent. [Pg.77]

It is now apparent that bacteria have developed resistance to heavy metals and the detoxifying process is initiated and controlled by metallo-regulatory proteins which are able selectively to recognize metal ions. MerR is a small DNA-binding protein which displays a remarkable sensitivity to Hg +. The metal apparently binds to S atoms of cysteine and this has been a major incentive to recent work on Hg-S chemistry. [Pg.1226]

Such inorganic compounds as sulphates of heavy metals and calcium [27], sulphites of calcium and potassium, salts of nickel [28] have been reported as thermostabilizers of polyolefins. [Pg.83]

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... [Pg.119]

Reduction of exhaust emissions is being tackled in two ways by engineers, including precombustion and postcombustion technology. One of the most effective methods now being researched and adopted includes use of synthetic fuel made from natural gas. This fuel is crystal clear, and just like water, it has no aromatics, contains no sulfur or heavy metals, and when used with a postcombustion device such as a catalytic converter any remaining NO, or other emissions can be drastically reduced. Estimates currently place the cost of this fuel at 1.50 per gallon, with availability in 2004 to meet the next round of stiff EPA exhaust emission standards. [Pg.335]

Some heavy metals and semi-metals are quite toxic (chromium, lead, and antimony) and expensive care is needed to prevent them from being dispersed in the environment. Lead in gasoline and paint has been... [Pg.775]

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. [Pg.776]

Pretreating the feedstocks with hydrogen is not always effective in reducing heavy metals, and it is expensive. Other means that proved successful are modifying the composition and the microporous structure of the catalyst or adding metals like Sb, Bi or Sn, or Sb-Sn combination. Antimony organics have been shown to reduce by 50% gas formation due to metal contaminants, especially nickel. ... [Pg.72]


See other pages where Heavy metals and is mentioned: [Pg.7]    [Pg.440]    [Pg.317]    [Pg.287]    [Pg.97]    [Pg.248]    [Pg.283]    [Pg.541]    [Pg.556]    [Pg.153]    [Pg.153]    [Pg.154]    [Pg.152]    [Pg.388]    [Pg.165]    [Pg.194]    [Pg.293]    [Pg.145]    [Pg.12]    [Pg.2214]    [Pg.34]    [Pg.30]    [Pg.33]    [Pg.336]    [Pg.90]    [Pg.143]    [Pg.399]    [Pg.757]   
See also in sourсe #XX -- [ Pg.163 ]




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A Note on Heavy Atoms and Transition Metals

Abrasive Blasting and Heavy-Metal Contamination

Acid Drainage Prevention and Heavy Metal Removal Technologies

Adsorption of heavy metals and metalloid

Analysis of Heavy and Transition Metals

Analysis of Heavy and Transition Metals with Spectrophotometric Detection

Biophysico-Chemical Processes of Heavy Metals and Metalloids in Soil Environments

Dioxins, Furans and Heavy Metals

Emission of gaseous components and heavy metals

Environmental Pollution and Heavy Metals

Estimates of heavy metal flows to and from the atmosphere

Food Contaminants Heavy Metals, Pesticides, and Toxic Substances

Heavy Atoms and Transition Metals

Heavy Metal Toxicity and Essentiality

Heavy Metals and Organic Pollutants in the Sediment Cores

Heavy metals and ammonium

Heavy metals and metalloids

Heavy metals and organics

Heavy metals and soil type

Heavy metals cadmium, lead, mercury and

Heavy metals, mercury and aluminium

Input flows of radionuclides, heavy metals, and oil hydrocarbons

Nephrotoxicity and Heavy Metal Chelates

Propoxur and Heavy Metals

Reactions with Heavy Metals and their Ions

Regulatory Bodies for Heavy Metals and Metal Ions

Removal of Precipitated Heavy Metals, Solids and Oils

Selectivity Heavy metals and

Simultaneous removal of heavy metals and

Soil Sampling and Heavy Metal Determination

Sources of heavy metals and their distribution in the environment

Specific Insight for Removal of Mixed Heavy Metals, Including Cr, As, and Hg

Total Content and Profile Distribution of Heavy Metals in the Affected Soils

Uni- and Bivalent Heavy Transition Metal Ions

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