Introduction Lanthanum (La) is a member of the rare earth elements (REEs), which consist of a group of 15 trivalent metallic elements with similar properties. Lanthanum is mostly dangerous in the working environment, due to the fact that damps and gasses can be inhaled with air. This can cause lung embolism, especially during long-term exposure. Lanthanum can also cause cancer with humans, as it enlarges the chances of lung cancer when it is inhaled. Finally, it can be a threat to the liver when it accumulates in the human body.
Historical Development of Atomic Structure Yazan Fahmawi Sept. 30, 1995 T3 IBS Chemistry Ms. Redman The idea behind the "atom" goes back to the Ancient Greek society, where scientists believed that all matter was made of smaller, more fundamental particles called elements. They called these particles atoms, meaning "not divisible." Then came the chemists and physicists of the 16th and 17th centuries who discovered various formulae of various salts and water, hence discovering the idea of a molecule. Then, in 1766 was born a man named John Dalton born in England. He is known as the father of atomic theory because he is the one who made it quantitative, meaning he discovered many masses of various elements and, in relation, discovered the different proportions which molecules are formed in (i.e.
But increase in its concentration can cause several consequences such as growth and development abnormalities, lung cancer, chromate ulcer, kidney damage skin irritation and wide range of other illness (Thiele 1995). Chromium exist in two stable oxidation state in environment Cr6+ and Cr3+ out of these two Cr6+ is more toxic and able to transport across the cell membrane. Due to its structural similarity with sulphate, chromate uses sulphate transporters for their entery inside the cytoplasm. Hexavalent form of chromium itself not able to bind with DNA, RNA and Proteins inside cytoplasm firstly it reduced into Cr3+ which show binding ability with these molecules. During reduction of Cr6+ to Cr3+ it generates reactive oxidation species which damage DNA.
Combination of autoantibodies and auto antigens form, circulate, and are deposited within capillary complexes, renal glomeruli, renal interstitial, serosal membranes and the choroid plexus and in the pleural vasculature (McDonald, Compston, Edan, Goodkin, Hartung, & Lublin, 2001). The formation of these immune complexes triggers an inflammatory response, leading to chronic destruction of host tissue. Lupus has very complex symptoms that are not easy to identify. There are however chief complain that you likely to hear from your patient and this is fatigue, headache, fever, malaise, nausea, vomiting, anorexia, weight loss and abdominal pain (Wong, Ho and Lam, 2000). Lupus has signs and symptoms that are ranging from internal and physical symptoms.
This impact has shown to increase the amount of dibutyl phthalate in the Great Lakes, among other bodies of water, which is a problem because dibutyl phthalate is very toxic to aquatic organisms. During the dispo... ... middle of paper ... ...hanolamine derivatives are used more commonly in many cosmetics. 3. Diethanolamine is a nitrogen containing substance, and nitrosamines have been clearly identified as a carcinogen. Diethanolamine has also been proved to induce asthma, cause shortness of breath, or cause irritation of the eyes or skin.
In 1972 Frenchman Antoine Laurent Lavoisier discover the no mater what happens a substance always has the same weight. In the late 1700’s another Frenchman, Proust, discovert that elements can be combined to make different compounds, and that certain proportions had to be used. This became know as “law of definite proportions”. A few years later an English chemist, John Dalton, a fan of Boyle worked on Proust’s theory and came up with “the law of multiple proportions”. Dalton soon came up with ‘weight’ theories of the atom a discovered that hydrogen was the lightest.
Oxygen can be condensed to a pale blue liquid, which is very magnetic. It is produced by compressing the liquid. Oxygen used to be the official standard for the atomic weights of elements. The chemists used natural oxygen, to which the value of 16 was assigned. In 1961, however, carbon-12 replaced oxygen as the standard.
Title : Phytoremediation of Heavy Metals laden Waste Water using Duckweed species INTRODUCTION Presservation of the environment quality is one of the major concern of this century. Our biosphere is getting degraded by the release of natural and synthetic substances that can cause deleterious effects on living organisms. Among all the pollutants , heavy metals are easily transported and accumuted in the environment. Many industries like textile and steel, electroplating, metal producing release heavy metal such as cadmium, copper, chromium, nickel and lead in the wastewater (Demirenzen et al., 2007). Most of the heavy metals are toxic or carcinogenic in nature and pose a threat to human health and the environment (Shakibaie et al., 2008; Vinodhini and Narayanan, 2009).
Chlorine Chlorine is (at room temperature) a greenish-yellow gas that can be readily liquefied at 5170 Tarr or 6.8 atmospheres, at 20 C (68 F), and has a very disagreeable odor. It’s Element Symbol is Cl, atomic number is 17, and atomic mass is 35.453. Chlorine’s melting point is -101 C or 149.8 F. The boiling point is -34.05 C or -29.29 F, at one atmosphere pressure. Chlorine is a member of the halogen group. Chlorine was discovered by Swedish scientist Karl Wilhelm in 1784, but he first thought it was a compound, rather than an element.
Uranium was discovered by Martin Heinrich Klaproth, a German chemist, in the mineral pitchblende (primarily a mix of uranium oxides) in 1789.Klaproth, as well as the rest of the scientific community, believed that the substance he extracted from pitchblende was pure uranium, it was actually uranium dioxide (UO2). After noticing that 'pure' uranium reacted oddly with uranium tetrachloride (UCl4), Radioactivity was first discovered in 1896 when Antoine Henri Becquerel, a French physicist, detected it from a sample of uranium. Today, uranium is obtained from uranium ores such as pitchblende, uraninite , carnotite and autunite as well as from phosphate rock , lignite (brown coal) and monazite sand . Since there is little demand for uranium metal, uranium is usually sold in the form of sodium diuranate , also known as yellow cake, or triuranium octoxide). Uranium, a radioactive element, was first mined in the western United States in 1871 by Dr. Richard Pierce, who shipped 200 pounds of pitchblende to London from the Central City Mining District.