2. Appearance: The appearance effect of "Townsend" is an international super mirror, each paragraph reflects the superb skills of our craftsmen, and every detail is unique. Tungsten and gold jewelry is hard to handle because of its hard material. It's really a mile away. Improper handling will leave sharp edges and corners, which are harmful to people's health, but the unique style of tungsten and gold jewelry cannot be reflected after processing. In dealing with these details, "Tunstall" has completely reached the state of exquisite workmanship, which is really "one point is too fat, one point is too thin", especially in the inner ring of tungsten gold ring, which is more comfortable and more personalized, reflecting our meticulous care for customers as an international brand "Tunstall" tungsten gold video.
3. size; Tungsten and gold jewelry is completely handmade, so it is very difficult and demanding to control the size. Townshend can control all dimensional tolerances within plus or minus two lines, which is rare even in the world. This is also a reason why Townshend can be recognized and prospered in the international market (please refer to the code certificate of China Bureau of Quality and Technical Supervision for specific size requirements). These precise size requirements are unmatched by other tungsten and gold jewelry.
4. Environmental protection and safety: This is also the most concerned issue for international and domestic consumers at present. Tungsten-gold jewelry is also an alloy in essence. If it is an alloy, it must contain other metals. Our "Tunstall" has passed the SGS certification of EU, UKAS certification of UK and HKPC certification, as well as all the quality and radioactivity tests in Chinese mainland, and is allowed to be sold in European and American markets, so you can wear it with confidence. Tunstall won't do any harm to human body. Xushujunsg2010-02-17: 23:17 Chemically, metals are divided into heavy metals and light metals according to their densities, and metals with densities greater than 5g/cm3 are often called heavy metals, such as gold, silver, copper, lead, zinc and nickel.
Among them, lead, mercury, chromium, arsenic and cadmium are the most harmful to human body. These heavy metals can not be decomposed in water, and combine with other toxins in water to produce more toxic organic substances. Others harmful to human body: aluminum, cobalt, vanadium, antimony, manganese, tin, thallium, etc.
The harm of heavy metals to human body is common:
Lead: It harms human brain cells, leading to cancer and mutation.
Mercury: It sinks directly into the liver after eating, which is harmful to the brain and vision. Natural water containing 0.0 1 mg per liter of water is highly toxic.
Chromium: It will cause numbness of limbs and mental abnormality.
Arsenic: It will make the skin pigmentation and lead to abnormal keratinization.
Cadmium: causes hypertension and cardiovascular and cerebrovascular diseases; Destroy bone calcium, resulting in renal insufficiency.
Aluminum: long-term accumulation, causing mental retardation to children; Lead to memory loss in middle-aged people; Causing dementia in the elderly.
Cobalt: It can cause radiation damage to the skin.
Vanadium: It hurts the heart and lungs and causes abnormal cholesterol metabolism.
Antimony: With arsenic, silver jewelry will turn brick red and be radioactive to the skin.
Selenium: If you take too much, you will get sick.
Thallium: It can make people suffer from polyneuritis.
Manganese: Too much will make people hyperthyroidism.
Tin: Lead is an important component of the ancient giant poison' pigeon', which solidified into pieces after entering the abdomen and fell to death.
Lead and aluminum are the most harmful metals in our daily life, and more importantly, they are the killers of children's intelligence. These two metals are mostly found in foods with antiseptic additives, especially in children's snacks. Lead and mercury are harmful to human health. Lead, aluminum and mercury are the most frequently contacted metals, while others are seldom contacted.
For reference only. Of the chemical elements in 109, 83 are metals, and metals with a density above 5 are collectively referred to as heavy metals. It can be said that metal has become a part of our life. Heavy metal pollution often refers to heavy metals with obvious biological toxicity such as mercury, cadmium, lead, chromium and metalloid arsenic. Heavy metals can interact strongly with protein and various enzymes in human body, making them inactive, and may also accumulate in some organs of human body. If it exceeds the tolerance limit of human body, it will cause acute poisoning, subacute poisoning, chronic poisoning and other hazards.
This kind of harm mainly has three aspects:
First, it is harmful to the liver. The combination of heavy metals with hematoporphyrin in blood will damage the liver, leading to cirrhosis and liver cancer.
The second is to damage the blood circulation system. After heavy metal poisoning, the blood viscosity increases and the oxygen content is low, which will lead to systemic tightness, shock and other symptoms.
The third is to harm the nervous system, inhibit and interfere with the function of the nervous system.
For children and the elderly, heavy metals are more harmful. Because children's immunity is low, the metabolism of the elderly is slow, which will lead to difficulties in discharging heavy metals.
In daily life, we mainly ingest heavy metals through the following three ways.
First, environmental pollution (mainly air pollution, water pollution and soil pollution) leads to excessive heavy metals in aquatic products, fruits and vegetables, among which aquatic products are the most serious. There are two main sources of heavy metals in vegetables: heavy metals in soil are absorbed by plants through soil solution, and heavy metals in air are directly absorbed by plant leaves. Fruits are less polluted by heavy metals than vegetables, because the problem of sewage irrigation of vegetables is more serious, but the peel of fruits will also be affected to some extent.
Second, food is contaminated during processing or storage. In the past, popcorn made in a large pot on the street was a serious problem because the container coating contained lead. Preserved eggs are also a kind of food easily contaminated by lead. Food packaging also has some potential dangers. Due to printing quality problems, lead in some packaging inks will "pollute" food.
The third is to eat heavy metals through daily necessities. This must first mention the heavy metals in drinking water. There are two main aspects of drinking water pollution in China:
One is mercury pollution. The direct discharge of industrial wastewater makes mercury pollution penetrate into groundwater, but it is difficult to dispose of mercury when tap water is treated. This kind of pollution mainly exists in some small towns where industrial wastewater is discharged at will.
Second, lead pollution mainly occurs in copper water meters, faucets and lead-containing galvanized water pipes. The longer the water pipe is used, the lower the PH value of tap water and the greater the lead pollution. Stainless steel tableware and ceramic tableware that people use daily are also important sources of heavy metal pollution. In order to prevent rust, stainless steel tableware will contain a certain amount of chromium and nickel. If the coating on the surface of tableware is destroyed, chromium and nickel will precipitate, which is harmful to human health. But the color patterns printed on the glaze of ceramic tableware all contain a certain amount of lead.
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Lead is a heavy metal that is often exposed to in daily life, and exists in many industries such as vehicles and welding.
In addition, mercury, chromium and cadmium are also exposed more. It is widely used in industry.
Lead, mercury, chromium and cadmium will accumulate, and it is difficult to excrete them without manual intervention (treatment).
There is not enough evidence that aluminum can cause diseases or genetic problems in general contact. Other metals are rarely exposed to excess unless they are related to your work. Lead, mercury and so on! Heavy metals generally refer to metals with a density greater than 4.5 grams per cubic centimeter, and there are about 45 kinds, all of which belong to transition elements. Such as copper, lead, zinc, iron, cobalt, nickel, manganese, cadmium, mercury, tungsten, molybdenum, gold and silver. Although heavy metals such as manganese, copper and zinc are trace elements needed for life activities, most heavy metals such as mercury, lead and cadmium are not necessary for life activities, and all heavy metals are toxic to human body if they exceed a certain concentration.
At present, there is no strict and unified definition of heavy metals. As far as environmental pollution is concerned, heavy metals refer to mercury, cadmium, lead and "metalloid"-arsenic and other heavy metals with significant biological toxicity. Lead, mercury, arsenic and cadmium are the most harmful to human body. These heavy metals can't be decomposed in water, and their toxicity is amplified after drinking, and they combine with other toxins in water to produce more toxic organic substances.
Heavy metals do great harm to human body. Common ones are:
Mercury: It sinks directly into the liver after ingestion, which is extremely harmful to the brain, nerves and vision. Natural water contains 0.0 1 mg per liter of water, which will cause human poisoning.
Cadmium: causes hypertension and cardiovascular and cerebrovascular diseases; Damage to bones, liver and kidneys, and can lead to renal failure.
Lead: It is one of the most toxic heavy metal pollution. Once in the human body, it is difficult to eliminate. It can directly harm human brain cells, especially the nervous system of the fetus, and can cause congenital mental retardation; Will cause dementia to the elderly and so on. In addition, it also has carcinogenic and mutagenic effects.
Cobalt: It can cause radiation damage to the skin.
Vanadium: It hurts the heart and lungs and causes abnormal cholesterol metabolism.
Antimony: With arsenic, silver jewelry will turn brick red and be radioactive to the skin. It can also damage bones, liver and kidneys.
Thallium: It can cause polyneuritis.
Manganese: Too much will make people hyperthyroidism. It can also damage vital organs.
Arsenic: As a component of arsenic, it is highly toxic and can lead to rapid death. Long-term exposure to a small amount can lead to chronic poisoning. And carcinogenicity.
Any of these heavy metals can cause headaches, dizziness, insomnia, forgetfulness, mental disorders, joint pain, stones, cancers (such as liver cancer, stomach cancer, intestinal cancer, bladder cancer, breast cancer, prostate cancer, Blackfoot disease and deformed children). Especially the cells, organs, skin, bones and spirit of digestive system and urinary system. 1. 1 the harm of lead (Pb)
People know a lot about lead pollution and its harm to human body. Lead is the only trace element that the human body does not need, and it can cause damage to almost all organs of the human body. Specifically, it affects the development of intelligence and bones, causes indigestion and endocrine disorders, leads to anemia, hypertension and arrhythmia, and destroys renal function and immune function. Even if there is only 0.0 1 microgram of lead in human body, it will do harm to health. Moreover, even if the blood lead level is significantly reduced after leaving the polluted environment or after treatment, the damaged organs and tissues can no longer be repaired, which will be accompanied by life. Studies and experiments show that children with high blood lead are behind children with low blood lead by 14, 14 and 13 points respectively, while the lead concentration per liter of blood increases by 100 microgram, while the height of children decreases by 1.3 cm. The harm of lead begins with the fetus. Lead mainly damages the nervous system and hematopoietic system. Because the fetal brain is more sensitive to the toxic effect of lead than the adult brain, the damage of lead to fetal development is manifested early after birth, which is not only poor physical development, but also poor intellectual development, which is also one of the reasons for mental retardation. Studies show that 90% of blood lead comes from food, and lead in water and food is the main reason for the increase of blood lead content. The earth produces 400,000 tons of lead dust every year, which can enter the human body through breathing; Soil is the largest lead reservoir in nature, and lead will be deposited in grains and vegetables, causing pollution [3,4].
1.2 harm of cadmium
Cadmium is a very toxic heavy metal, and most of its compounds are toxic substances. Cadmium is widely used, such as cadmium salt, cadmium vapor lamp, pigment, smoke bomb, alloy, electroplating, flux, standard battery, metallurgical deoxidizer, neutron absorption rod of atomic reactor and so on. For example, the pigment cadmium red consists of cadmium sulfide, cadmium selenide and barium sulfate; Cadmium yellow consists of cadmium sulfide and barium sulfate. Mining and smelting of metal ores, electroplating and pigments are the main man-made pollution sources of cadmium. Cadmium-containing mine wastewater pollutes the soil, grain and pasture on both sides of the river, and it will enter the human body through the food chain and accumulate slowly. Cadmium will replace calcium in bones and kidneys, which will severely soften bones. Cadmium toxicity is potential, the incubation period can be as long as 10 ~ 30 years, and it is not easy to detect in the early stage. Data show that the biological half-life of cadmium in human body is 20 ~ 40 years, and the toxicity of cadmium to human tissues and organs is various and extremely difficult to treat.
Hazards of 1.3 Hg
Mercury, that is, mercury, is a liquid metal that can evaporate at room temperature. Its vapor is colorless and tasteless, and it is seven times heavier than air. Mercury and its compounds are very toxic, especially the organic compounds of mercury are more toxic. Fish will be poisoned if they live in water with mercury content of 0.0 1 ~ 0.02 mg/L; People who eat 0. 1 g of mercury will be poisoned to death. Mercury and its compounds can invade human body through respiratory tract, skin or digestive tract. The food chain has considerable ability to enrich mercury, such as freshwater fish and phytoplankton, freshwater invertebrates, marine plants and marine animals. After entering human body, mercury accumulates in liver, kidney, brain, heart and bone marrow, causing neurotoxicity and deep tissue lesions. The toxicity of mercury is cumulative, which is often not easy to detect at first, and it takes years or even longer to react [5, 6].
1.4 Hazards of Chromium (Cr)
Chromium is a silvery white luster metal, which is non-toxic and chemically stable. Among chromium compounds, hexavalent chromium is the most toxic, followed by trivalent chromium. Chromium is an essential trace element for the life and health of mammals. Chromium deficiency can lead to atherosclerosis, but excessive chromium can cause harm to mammals. Chromic acid, dichromatic acid and their salts have irritating and burning effects on human mucosa and skin. These compounds enter the human body in the form of steam or dust, which will cause perforation of nasal septum, gastrointestinal diseases, leukopenia and lung diseases similar to asthma. Some people think that hexavalent chromium can induce lung cancer.
1.5 The hazards of polybrominated biphenyls and polybrominated diphenyl ethers (PBB) are major suspected carcinogens and potential carcinogens. After eating pork contaminated with PBBs, people will have severe headaches, severe burnout, gastrointestinal discomfort, stiff joints or swelling. From March 65438 to March 0968, a sensational "rice bran oil incident" occurred in Kyushu and Shikoku, Japan. At that time, polychlorinated biphenyls (PCBs), a debrominated heat carrier, leaked into rice bran oil, and people and animals were poisoned after eating it. At first, it was just eyelid edema, sweaty palms, and red pimples all over the body. Later, vomiting, nausea, decreased liver function, muscle pain, cough, and partial recovery occurred.
Polybrominated diphenyl ethers (PBDEs) are the main components of brominated flame retardants, and brominated flame retardants are one of the most abundant and widely used organic flame retardants. German scientists have found that PBDEs will react with flame retardant materials when decomposed at high temperature, resulting in toxic and carcinogenic PBDD and PBDF. A large number of PBDEs will affect human brain function, destroy ovarian function and reduce male fertility. Because PBDEs are highly stable compounds, bromine flame retardants are one of the permanent organic pollutants in the environment, and they are also the fastest chemical substances accumulated in human body and environment for half a century. According to experts' analysis, even if PBDEs are banned now, this chemical will still exist in the environment for decades.
2. The existing forms of six harmful components and their substitution.
Lead mainly exists in lead-containing solder, CRT glass, light bulbs, pigments, solid lubricants, rubber, lead-acid batteries, PVC heat stabilizers and so on. Among them, the solder of the circuit board is a crystal solder composed of 63% tin and 37% lead, and the melting point of this solder is 183℃. At present, lead-free welding technology and process can be used to replace the conventional welding process. Due to the different welding equipment, the materials of lead-free solder are also different. Manual welding generally uses tin copper, tin silver or tin silver copper, submerged arc welding and wave welding can use tin copper, and reflow welding can use tin silver and tin silver copper.
Cadmium mainly exists in switches, springs, connectors, housings, PCB, fuses, pigments and coatings, semiconductor photoelectric sensors and so on. In the field of low-voltage electrical appliances, silver tin oxide indium oxide (AgSnO2In2O3) can replace cadmium and silver cadmium oxide (AgCdO).
Mercury mainly exists in temperature controllers, sensors, relays, metal corrosives, batteries, preservatives, disinfectants, adhesives and so on. Rechargeable batteries such as Ni-MH and Li-ion can be used instead of mercury-containing batteries, and new thermostats and sensors without mercury can also be used.
Chromium (hexavalent) mainly exists in metal anticorrosive coatings, pigments, rust inhibitors, corrosion inhibitors, ceramic glazes and so on. Alkaline zinc plating can be used instead of chromium plating, and Cr3+ can be used instead of Cr6+ to reduce the harm to the environment, or the electroplated parts cannot be used.
Polybrominated biphenyls and polybrominated diphenyl ethers mainly exist in flame retardants, PCB, connectors, plastic shells and so on. Phosphorus flame retardants can be used instead of bromine flame retardants, and inorganic flame retardants such as magnesium hydroxide and aluminum hydroxide can also be used.
Gold, silver, copper, lead, zinc, nickel, cobalt, chromium, mercury, cadmium and many other metals. Heavy metals refer to metals with a specific gravity greater than 5 (generally, metals with a density greater than 4.5g per cubic centimeter), and there are about 45 kinds, such as copper, lead, zinc, iron, cobalt, nickel, manganese, cadmium, mercury, tungsten, molybdenum, gold and silver. Although heavy metals such as manganese, copper and zinc are trace elements needed for life activities, most heavy metals such as mercury, lead and cadmium are not necessary for life activities, and all heavy metals are toxic to human body if they exceed a certain concentration.
For example, the clinical manifestations of mercury poisoning include headache, dizziness, fatigue and fever. The symptoms of oral cavity and digestive tract are swelling and pain of gums, erosion and bleeding, loose teeth, pus overflowing from gingival sulcus, bad breath, nausea, vomiting, loss of appetite, abdominal pain and diarrhea. Red maculopapules can appear in skin contact, mainly distributed on limbs, head and face. A few patients may have renal damage, and some severe patients may have symptoms of acute interstitial pneumonia such as cough, chest pain, dyspnea and cyanosis.
Heavy metal poisoning can coagulate protein in the body, which can be seen from the chemistry book of senior three. If you are slightly poisoned, drink more milk. protein in milk will react with heavy metals, so as not to damage your body function. See a doctor immediately after drinking.
At present, there is no strict and unified definition of what heavy metals are. In terms of environmental pollution, heavy metals mainly refer to mercury, cadmium, lead, chromium, metalloid arsenic and other heavy metal elements with obvious biological toxicity. Heavy metals can't be biodegraded. On the contrary, they can be enriched thousands of times under the biomagnification of the food chain and eventually enter the human body. Heavy metals can interact strongly with protein and enzymes in human body, making them inactive, and may accumulate in some organs of human body, leading to chronic poisoning.
Heavy metal elements are discharged into rivers, lakes or oceans without treatment for some reasons, or enter the soil, so that these rivers, lakes, oceans and soils are polluted and cannot be biodegraded. If fish or shellfish accumulate heavy metals and are eaten by human beings, or heavy metals are absorbed by crops such as rice and wheat and are eaten by human beings, heavy metals will enter the human body and cause heavy metal poisoning, ranging from strange diseases (Minamata disease and bone pain). ) to serious death. Therefore, we should not eat too much seafood. We must thoroughly cook seafood before each meal to avoid eating bacteria.
heavy metal contamination
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The heavy metals mentioned in environmental pollution refer to heavy metals with obvious biological toxicity such as mercury, cadmium, lead, chromium and metalloid arsenic. There are five most toxic substances to human body: lead, mercury, chromium, arsenic and cadmium. These heavy metals can't be decomposed in water, and their toxicity is amplified after drinking, and they combine with other toxins in water to produce more toxic organic substances.
The harm of heavy metals to human body is common:
Lead: It harms human brain cells, leading to cancer and mutation.
Mercury: It sinks directly into the liver after eating, which is harmful to the brain and vision. Natural water contains 0 per liter of water. 0 1 mg, will be strongly poisoned.
Chromium: It will cause numbness of limbs and mental abnormality.
Cadmium: causes hypertension and cardiovascular and cerebrovascular diseases; Destroy bone calcium, resulting in renal insufficiency.
Lead is one of the most toxic heavy metal pollution, but once it enters the human body, it is difficult to eliminate it. Direct damage to human brain cells, especially fetal brain plate, can cause congenital shallow cerebral sulcus and mental retardation; Leading to dementia and brain death in the elderly.
Aluminum: Long-term accumulation, causing mental retardation to children; Lead to memory loss in middle-aged people; Causing dementia in the elderly.
Cobalt: It can cause radiation damage to the skin.
Vanadium: It hurts the heart and lungs and causes abnormal cholesterol metabolism.
Antimony: With arsenic, silver jewelry will turn brick red and be radioactive to the skin.
Thallium: It can make people suffer from polyneuritis.
Manganese: Too much will make people hyperthyroidism.
Tin: and lead are important components of the ancient giant poison' pigeon', which solidified into pieces after entering the abdomen and fell to death.
Zinc: Excessive intake will lead to zinc fever.
Iron: It catalyzes oxidation in human body, but excessive iron will destroy the basic components of cells, such as lipoic acid, protein and nucleic acid. It leads to the imbalance of other trace elements, especially the demand for calcium and magnesium.
Any of these heavy metals can cause headaches, dizziness, insomnia, forgetfulness, mental disorders, joint pain, stones, cancers (such as liver cancer, stomach cancer, intestinal cancer, bladder cancer, breast cancer, prostate cancer, Blackfoot disease and deformed children). Especially the cells, organs, skin, bones and spirit of digestive system and urinary system.
Nowadays, countries around the world pay more and more attention to environmental protection. They not only legislate to protect and purify the environment, but also spend a lot of manpower, material resources and financial resources to control air pollution, water pollution and chemical pollution. Brief introduction of Tian Zhen Tieguanyin 2010-02-1911:33: 36 tungsten and gold.
What is tungsten gold?
Tungsten gold (tungsten alloy; ; Tungsten alloy for short)
Tungsten and gold are made of tungsten and carbon alloys through special processing. At present, the annual output in the world is not high, but it is widely used in industry and is also the most popular jewelry material in the world. The hardness of tungsten gold is close to that of diamond, the texture is extremely firm, it hardly wears, the color is black and bright, and it never fades. It is a rare non-ferrous metal with great preservation and collection value. Tungsten gold is more durable than gold, platinum and titanium gold. Its hardness is 8-9m (Mohs hardness standard), which is 10 times that of gold, 5 times that of stainless steel and 4 times that of titanium gold, and it is comparable to diamonds.
Identification of tungsten and gold
How to identify the authenticity of tungsten and gold ornaments?
First, density identification method: the density of tungsten and gold is much higher than that of titanium steel, germanium, stainless steel and other alloys. It is very textured and heavy metal.
2. Hardness identification method: The hardness of tungsten gold is 8-9M (international Mohs hardness standard), which is close to natural diamond (10M) and much harder than gold, titanium, tungsten steel and stainless steel. There is almost no wear on the surface of tungsten gold jewelry. You can knock and scrape its surface with hard objects such as iron brushes or blades. Real tungsten gold jewelry will not produce cracks and scratches.
Third, naked eye identification method: tungsten gold itself has a black and bright metallic color, which has strong wear resistance and corrosion resistance. Even after special processing, it is as bright as ever under normal use. Under normal circumstances, it will not produce oxidation, fading, fragmentation, skin allergy and other phenomena.
Fourth, the price appraisal method: At present, the price of tungsten and gold jewelry in the world ranges from several hundred to several thousand, and there are several dozen pieces of goods on the market, so please pay attention to friends who like tungsten and gold jewelry.
Tungsten and gold maintenance
Maintenance of tungsten and gold ornaments
Simplicity, naturalness and decoration have become the theme style and development trend of tungsten and gold jewelry. Whether you want to buy this kind of products or not, if you go to the market, you will find a phenomenon: in pursuit of European and American fashion trends, tungsten and gold reflect the trend of luxury and brightness, firmness and permanence, and tungsten and gold diamond ornaments have become the favorite of more and more people. Just as tungsten and gold diamond ornaments enter the homes of ordinary people, its maintenance has become a very concerned issue. People like tungsten gold jewelry so much because it has the characteristics comparable to diamonds: no wear, no deformation, no discoloration and no harm to human body. So we don't have to worry about wearing it every day?
In fact, tungsten and gold ornaments don't need our extra care like diamonds and gold and silver. But we should also pay attention to some small details:
The unique black and bright luster of tungsten and gold jewelry will be obviously weakened once it is polluted by skin oil, soap, cosmetics and kitchen oil stains. So always use ordinary detergent to clean. Its cleaning is very simple, unlike diamonds and gold and silver, which need professional cleaning institutions to maintain.
It should be noted that tungsten and gold can be dissolved in the mixed acid of concentrated nitric acid and hydrofluoric acid, and can be corroded by oxidized molten salt (such as NaNO3), so the ornaments should be removed when doing relevant professional operations.