Oxidant is the component accounting for a larger proportion, what research more is inflammable and explosive caused hazards to human body, most of the past records in toxicology were the low toxicity categories, to skin and mucous membrane have strong irritation, causing dermatitis.
Some even have a strong corrosive, the larger toxic oxidant is trinitrotoluene, can cause the damage of the liver, blood, crystal and nervous system. Ammonium perchlorate is one of the main oxidants in composite solid propellant formulation, in the past reported it is less toxic, only to the skin have irritate effect, in recent years, the study found that it not only have a strong stimulating to the skin and mucous membranes, but also can cause chemical bronchitis, extensive pulmonary interstitial fibrosis, restrictive ventilatory dysfunction, small airways dispersion function decline if absorb large number. Long-term contact with ammonium peroxide, X-ray showed the pneumoconiosis degeneration, appears irregular shadows and ventilatory dysfunction. These information caused the concern of a majority of medical staff, but still need to confirm by a large number of population-based surveys. RDX gold and Orcutt gold is the commonly used oxidants in formula, a middle class drug substances, mainly cause nervous system poisoning; convulsions, anxiety, irritability, but quickly recover after stop working, and damage to the liver, the toxicity of Orcutt gold is smaller than RDX gold. In recent years, the newly developed nitroiminohexahydro nitro- tetrafluoroethane is high toxic class, to the nervous system, lung damage caused by pulmonary interstitial edema, pulmonary fibrosis, alveolar adenocarcinoma hyperplasia or atypical squamous metaplasia, so it should pay particular attention to its long-term effects.
Fuel accounted for about 20%, the common use metal powders have aluminum powder, boron powder, beryllium powder, zirconium dioxide and so on, are the high toxic, beryllium powder is highly toxic can cause lung granuloma nodules, induced cancer and liver damage, liver cells edema and necrosis. Currently used aluminum powder, aluminum powder with low toxicity, but in recent years, it reported that excessive intake of aluminum can cause lung, hematopoietic function and nervous system, central gyrus, hippocampus, extensive spinal cord lesions. Boron powder and zirconium powder with lower toxicity.
The use amount of adhesive is less than oxidizing agent, it mainly supplied the mainly elements of the propellant combustion, such as carbon, hydrogen, are the long chain polymers such as hydroxyl terminated polybutadiene, carboxyl end group polybutadiene, four oxygen furyl, oxirane polyether, polyethylene glycol, polysulfide rubber, etc. are the low toxicity class, certain chemical substances have skin sensitization effects. Hydroxyl terminated polybutadiene is slightly toxic substance, no irritation to the skin and mucous membranes, but have a strong sensitization, population-based surveys show that there are 65% suffered from contact dermatitis.
Curing agent and function adjusting agents, heterocycle class such as propylene imine, ethyleneimine, phosphinyl aziridine, isophthaloyl trimethylene imine are good performance curing agent, bonding agent, belonging to the high poison class, have significant damage to the kidneys and reproductive system, and mutagenic, carcinogenic and teratogenic effects, so the long-term effects can not be ignored. The other is the isocyanates, such as toluene diisocyanate, isophorone diisocyanate, ethylene diamine, m-phenylenediamine are with a strong stimulation and sensitization effect, and cause lung small airway function decline, bronchitis, bronchial asthma, dermatitis.
The combined effects, composite solid propellant is consisting of a variety of chemical substances, the combined effects of several poisons increasing the chance of the operator poisoning. A3 plasticizers constituted by bis (2.2 - dinitropropyl) acetal and bis ( 2,2- dinitro- propyl) acetal, two kinds of low toxicity substances mixed with to increase its toxicity, the blood methemoglobin increase and cause liver and kidney damage, is the combined effects. Composite solid propellant combustion into gases while to fire, its components have sulfur dioxide, nitrogen oxides, hydrogen chloride, hydrogen fluoride, ammonia, cyanide, also can produce the combined effects.
Source:http://www.mhcmp.com
The application of tungsten in various industries
Steel Industry Most of tungsten applied in the production of special steels. The widely used high-speed steel was containing 9-24% of tungsten, 3.8-4.6% of chromium, 1-5% of vanadium, 4-7% of cobalt, 0.7-1.5% of carbon.
Magic effects of coconut oil
According to records, coconut oil can be regarded as the nobility of skin care plant extracts. It was rich in exotic tension of tropical plants, which can enhance the contractile force of the pores, perfectly beautify and nourish the skin.
Exploring the Potentials of Nano-Aluminum Powder
Nano-aluminum powder, a material with remarkable properties due to its minuscule particle size, is revolutionizing various industries with its high reactivity and large specific surface area. Unlike its bulk counterpart, nano-aluminum powder begins to oxidize at a lower temperature of 550°C, compared to the 950°C oxidation point of ordinary aluminum. This lower ignition energy and full combustion without apparent cohesion make it a superior choice for applications requiring high energy and efficiency. The unique characteristics of nano-aluminum powder, such as faster burning rates and greater heat release, are largely influenced by its synthesis method, which determines its particle size, surface area, and shape.
