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51-432: The term raw material denotes materials in unprocessed or minimally processed states such as raw latex , crude oil , cotton , coal , raw biomass , iron ore , plastic , air , logs , and water . The term secondary raw material denotes waste material which has been recycled and injected back into use as productive material. Supply chains typically begin with the acquisition or extraction of raw materials. For example,

102-424: A "second skin" effect. Synthetic latices are used in coatings (e.g., latex paint) and glues because they solidify by coalescence of the polymer particles as the water evaporates. These synthetic latices therefore can form films without releasing potentially toxic organic solvents in the environment. Other uses include cement additives and to conceal information on scratchcards . Latex, usually styrene -based,

153-439: A better protection to the plant from enemies than all the thorns, prickles, or hairs that could be provided. In this plant, so copious and so distasteful has the sap become that it serves a most important purpose in its economy. Evidence showing this defense function include the finding that slugs will eat leaves drained of their latex but not intact ones, that many insects sever the veins carrying latex before they feed, and that

204-406: A branching system extending throughout the plant. In many euphorbs , the entire structure is made from a single cell – this type of system is known as a non-articulated laticifer , to distinguish it from the multi-cellular structures discussed above. In the mature plant, the entire laticiferous system is descended from a single cell or group of cells present in the embryo . The laticiferous system

255-442: A complete solid solution at temperatures above 950 °C (1,740 °F). Hematite occurs naturally in black to steel or silver-gray, brown to reddish-brown, or red colors. It is mined as an important ore mineral of iron . It is electrically conductive. Hematite varieties include kidney ore , martite ( pseudomorphs after magnetite ), iron rose and specularite ( specular hematite). While these forms vary, they all have

306-541: A decrease in temperature at 260 K (−13 °C) is caused by a change in the anisotropy which causes the moments to align along the c axis. In this configuration, spin canting does not reduce the energy. The magnetic properties of bulk hematite differ from their nanoscale counterparts. For example, the Morin transition temperature of hematite decreases with a decrease in the particle size. The suppression of this transition has been observed in hematite nanoparticles and

357-563: A lack of raw materials as a reason for their supply chain issues. Forecasting for 2023, 50% of respondents expect a reduced availability of raw materials in the US to drive supply chain disruptions. Raw materials markets are affected by consumer behavior, supply chain uncertainty, manufacturing disruptions, and regulations, amongst other factors. This results in volatile raw materials markets that are difficult to optimize and manage. Companies can struggle when faced with raw material volatility due to

408-461: A lack of understanding of market demands, poor or no visibility into the indirect supply chain, and the time lag of raw materials price changes. Volatility in the raw materials markets can also be driven by natural disasters and geopolitcal conflict. The COVID-19 pandemic disrupted the steel industry, and once demand rebounded, prices increased 250% in the US . The Russian invasion of Ukraine caused

459-405: A latex allergy. Latex-fruit syndrome Many people with latex allergy also experience allergic reactions to certain fruits. This association has led to research regarding latex-fruit syndrome (LFS). This is a phenomenon characterized by cross-reactivity between natural latex rubber allergens and certain fruit allergens, leading to allergic reactions in sensitized individuals. It was described for

510-531: A lower-allergen substitute. Additionally, chemical processes may be employed to reduce the amount of antigenic protein in Hevea latex, yielding alternative materials such as Vytex Natural Rubber Latex which provide significantly reduced exposure to latex allergens. About half of people with spina bifida are also allergic to natural latex rubber. People who have had multiple surgeries and who have had prolonged exposure to natural latex are also more susceptible to

561-647: A rust-red streak. Hematite is not only harder than pure iron, but also much more brittle . Maghemite is a polymorph of hematite (γ- Fe 2 O 3 ) with the same chemical formula, but with a spinel structure like magnetite. Large deposits of hematite are found in banded iron formations . Gray hematite is typically found in places that have still, standing water, or mineral hot springs , such as those in Yellowstone National Park in North America . The mineral may precipitate in

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612-425: A two-line ferrihydrite precursor prepared from solution. Hematite exhibited temperature-dependent magnetic coercivity values ranging from 289 to 5,027 oersteds (23–400 kA/m). The origin of these high coercivity values has been interpreted as a consequence of the subparticle structure induced by the different particle and crystallite size growth rates at increasing annealing temperature. These differences in

663-452: A usable state. Metallic ores are first processed through a combination of crushing, roasting, magnetic separation, flotation, and leaching to make them suitable for use in a foundry . Foundries then smelt the ore into usable metal that may be alloyed with other materials to improve certain properties. One metallic raw material that is commonly found across the world is iron , and combined with nickel , this material makes up over 35% of

714-426: Is a clay that is colored by varying amounts of hematite, varying between 20% and 70%. Red ochre contains unhydrated hematite, whereas yellow ochre contains hydrated hematite ( Fe 2 O 3  ·  H 2 O ). The principal use of ochre is for tinting with a permanent color. Use of the red chalk of this iron-oxide mineral in writing, drawing, and decoration is among the earliest in human history. To date,

765-598: Is a pigment used in traditional Swedish house paints. Originally, it was made from tailings of the Falu mine. The spectral signature of hematite was seen on the planet Mars by the infrared spectrometer on the NASA Mars Global Surveyor and 2001 Mars Odyssey spacecraft in orbit around Mars. The mineral was seen in abundance at two sites on the planet, the Terra Meridiani site, near

816-489: Is actively moved to the area of injury; in the case of Cryptostegia grandiflora , latex more than 70 cm from the site of injury is mobilized. The large hydrostatic pressure in this vine enables an extremely high flow rate of latex. In a 1935 report the botanist Catherine M. Bangham observed that "piercing the fruit stalk of Cryptostegia grandiflora produced a jet of latex over a meter long, and maintained [this jet] for several seconds." The clotting property of latex

867-510: Is also slow. Hematite Hematite ( / ˈ h iː m ə ˌ t aɪ t , ˈ h ɛ m ə -/ ), also spelled as haematite , is a common iron oxide compound with the formula, Fe 2 O 3 and is widely found in rocks and soils . Hematite crystals belong to the rhombohedral lattice system which is designated the alpha polymorph of Fe 2 O 3 . It has the same crystal structure as corundum ( Al 2 O 3 ) and ilmenite ( FeTiO 3 ). With this it forms

918-469: Is also used in immunoassays . Some people only experience a mild allergy when exposed to latex, with symptoms such as eczema , contact dermatitis , or developing a rash . Others have a serious latex allergy , and exposure to latex products such as latex gloves can cause anaphylactic shock . Guayule latex has only 2% of the levels of protein found in Hevea latices, and it is being researched as

969-432: Is also used to refer to natural latex rubber , particularly non- vulcanized rubber. Such is the case in products like latex gloves , latex condoms , latex clothing , and balloons . Latex : Colloidal dispersion of polymer particles in a liquid. Synthetic latex : Latex obtained as a product of an emulsion , mini-emulsion, micro-emulsion, or dispersion polymerization . The cells ( laticifers ) in which latex

1020-469: Is attributed to the presence of impurities, water molecules and defects in the crystals lattice. Hematite is part of a complex solid solution oxyhydroxide system having various contents of H2O (water), hydroxyl groups and vacancy substitutions that affect the mineral's magnetic and crystal chemical properties. Two other end-members are referred to as protohematite and hydrohematite. Enhanced magnetic coercivities for hematite have been achieved by dry-heating

1071-493: Is derived from the Greek word for blood, αἷμα (haima) , due to the red coloration found in some varieties of hematite. The color of hematite is often used as a pigment . The English name of the stone is derived from Middle French hématite pierre , which was taken from Latin lapis haematites c. the 15th century, which originated from Ancient Greek αἱματίτης λίθος ( haimatitēs lithos , "blood-red stone"). Ochre

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1122-474: Is found in the poppy family and in the rubber trees ( Para rubber tree , members of the family Euphorbiaceae , members of the mulberry and fig family , such as the Panama rubber tree Castilla elastica ), and members of the family Asteraceae . For instance, Parthenium argentatum the guayule plant, is in the tribe Heliantheae ; other latex-bearing Asteraceae with articulated laticifers include members of

1173-430: Is found make up the laticiferous system, which can form in two very different ways. In many plants, the laticiferous system is formed from rows of cells laid down in the meristem of the stem or root . The cell walls between these cells are dissolved so that continuous tubes, called latex vessels, are formed. Since these vessels are made of many cells, they are known as articulated laticifers . This method of formation

1224-455: Is functional in this defense since it limits wastage and its stickiness traps insects and their mouthparts. While there exist other explanations for the existence of latex including storage and movement of plant nutrients, waste, and maintenance of water balance that "[e]ssentially none of these functions remain credible and none have any empirical support". The latex of many species can be processed to produce many materials. Natural rubber

1275-595: Is present in all parts of the mature plant, including roots, stems, leaves , and sometimes the fruits . It is particularly noticeable in the cortical tissues. Latex is usually exuded as a white liquid, but is some cases it can be clear, yellow or red, as in Cannabaceae . Latex is produced by 20,000 flowering plant species from over 40 families . These include both dicots and monocots . Latex has been found in 14 percent of tropical plant species, as well as six percent of temperate plant species. Several members of

1326-625: Is the Democratic Republic of the Congo . Latex Latex is an emulsion (stable dispersion) of polymer microparticles in water. Latices are found in nature , but synthetic latices are common as well. In nature, latex is found as a milky fluid , which is present in 10% of all flowering plants (angiosperms). It is a complex emulsion that coagulates on exposure to air, consisting of proteins , alkaloids , starches , sugars , oils , tannins , resins , and gums . It

1377-496: Is the most important product obtained from latex; more than 12,000 plant species yield latex containing rubber, though in the vast majority of those species the rubber is not suitable for commercial use. This latex is used to make many other products including mattresses , gloves , swim caps , condoms , catheters and balloons . Dried latex from the opium poppy is called opium , the source of several useful analgesic alkaloids such as codeine , thebaine , and morphine ,

1428-512: Is usually exuded after tissue injury. In most plants, latex is white, but some have yellow, orange, or scarlet latex. Since the 17th century, latex has been used as a term for the fluid substance in plants, deriving from the Latin word for "liquid". It serves mainly as defense against herbivorous insects . Latex is not to be confused with plant sap ; it is a distinct substance, separately produced, and with different functions. The word latex

1479-477: The Opportunity rover showed a significant amount of hematite, much of it in the form of small " Martian spherules " that were informally named "blueberries" by the science team. Analysis indicates that these spherules are apparently concretions formed from a water solution. "Knowing just how the hematite on Mars was formed will help us characterize the past environment and determine whether that environment

1530-483: The Cichorieae , a clade whose members produce latex, some of them in commercially interesting amounts. This includes Taraxacum kok-saghyz , a species cultivated for latex production. In the milkweed and spurge families, on the other hand, the laticiferous system is formed quite differently. Early in the development of the seedling, latex cells differentiate, and as the plant grows these latex cells grow into

1581-514: The European Commission notes that food supply chains commence in the agricultural phase of food production. A 2022 report on changes affecting international trade noted that improving sourcing of raw materials has become one of the main objectives of companies reconfiguring their supply chains. In a 2022 survey conducted by SAP , wherein 400 US-based leaders in logistics and supply chain were interviewed, 44% of respondents cited

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1632-585: The Morin transition at 250 K (−23 °C), and a canted antiferromagnet or weakly ferromagnetic above the Morin transition and below its Néel temperature at 948 K (675 °C), above which it is paramagnetic . The magnetic structure of α-hematite was the subject of considerable discussion and debate during the 1950s, as it appeared to be ferromagnetic with a Curie temperature of approximately 1,000 K (730 °C), but with an extremely small magnetic moment (0.002  Bohr magnetons ). Adding to

1683-528: The Upper Rhine . Rich deposits of hematite have been found on the island of Elba that have been mined since the time of the Etruscans . Underground hematite mining is classified as carcinogenic hazard to humans. Hematite shows only a very feeble response to a magnetic field . Unlike magnetite, it is not noticeably attracted to an ordinary magnet. Hematite is an antiferromagnetic material below

1734-628: The water to create very stable and hard materials. Without the presence of clay on the riverbanks of the Tigris and Euphrates in the Fertile Crescent, such kilns would have been impossible for people in the region to have produced. Using these kilns, the process of metallurgy was possible once the Bronze and Iron Ages came upon the people that lived there. Many raw metallic materials used in industrial purposes must first be processed into

1785-724: The Martian equator at 0° longitude, and the Aram Chaos site near the Valles Marineris . Several other sites also showed hematite, such as Aureum Chaos . Because terrestrial hematite is typically a mineral formed in aqueous environments or by aqueous alteration, this detection was scientifically interesting enough that the second of the two Mars Exploration Rovers was sent to a site in the Terra Meridiani region designated Meridiani Planum . In-situ investigations by

1836-520: The basis for red, purple, and brown iron-oxide pigments, as well as being an important component of ochre, sienna, and umber pigments. The main producer of hematite for the pigment industry is India, followed distantly by Spain. As mentioned earlier, hematite is an important mineral for iron ore. The physical properties of hematite are also employed in the areas of medical equipment, shipping industries, and coal production. Having high density and capable as an effective barrier against X-ray passage, it often

1887-634: The earliest known human use of the powdery mineral is 164,000 years ago by the inhabitants of the Pinnacle Point caves in what now is South Africa, possibly for social purposes. Hematite residues are also found in graves from 80,000 years ago. Near Rydno in Poland and Lovas in Hungary red chalk mines have been found that are from 5000 BC, belonging to the Linear Pottery culture at

1938-497: The eras. In Roman times, the pigment obtained by finely grinding hematite was known as sil atticum . Other names for the mineral when used in painting include colcotar and caput mortuum . In Spanish, it is called almagre or almagra , from the Arabic al-maghrah , red earth, which passed into English and Portuguese. Other ancient names for the pigment include ochra hispanica , sil atticum antiquorum , and Spanish brown . It forms

1989-428: The first sources of iron ore is bog iron . Bog iron takes the form of pea-sized nodules that are created under peat bogs at the base of mountains. Places with plentiful raw materials and little economic development often show a phenomenon known as " Dutch disease " or the " resource curse ", which occurs when the economy of a country is mainly based upon its exports because of its method of governance. An example of this

2040-710: The first time by Blanco et al. in 1994. In a 2024 comprehensive review by Gromek et al., the last 30 years of research on LFS were summarized, focusing on its prevalence, common cross-reactions, and clinical manifestations. The review found that the prevalence of LFS in latex-allergic patients varies widely, ranging from 4% to 88%, depending on diagnostic methods, geographical regions, and study populations. The most commonly implicated fruits in LFS include banana, avocado, kiwifruit, and papaya. Clinical manifestations are predominantly systemic, with 73% of hypersensitivity symptoms being systemic and 27% localized. Gromek et al. also highlighted

2091-447: The fungal kingdom also produce latex upon injury, such as Lactarius deliciosus and other milk-caps . This suggests it is the product of convergent evolution and has been selected for on many separate occasions. Latex functions to protect the plant from herbivores. The idea was first proposed in 1887 by Joseph F. James, who noted that latex of milkweed carries with it at the same time such disagreeable properties that it becomes

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2142-610: The growth rates are translated into a progressive development of a subparticle structure at the nanoscale (super small). At lower temperatures (350–600 °C), single particles crystallize. However, at higher temperatures (600–1000 °C), the growth of crystalline aggregates, and a subparticle structure is favored. Hematite is present in the waste tailings of iron mines . A recently developed process, magnetation , uses magnets to glean waste hematite from old mine tailings in Minnesota 's vast Mesabi Range iron district. Falu red

2193-411: The latex of Asclepias humistrata (sandhill milkweed ) kills by trapping 30% of newly hatched monarch butterfly caterpillars. Other evidence is that latex contains 50–1000× higher concentrations of defense substances than other plant tissues. These toxins include ones that are also toxic to the plant and consist of a diverse range of chemicals that are either poisonous or " antinutritive. " Latex

2244-441: The latter two of which can then further be used in the synthesis and manufacture of other (typically stronger) opioids for medicinal use, and of heroin for the illegal drug trade . The opium poppy is also the source of medically useful non-analgesic alkaloids, such as papaverine and noscapine . Latex is used in many types of clothing . Worn on the body (or applied directly by painting), it tends to be skin-tight , producing

2295-577: The material in the Earth's inner and outer core . The iron that was initially used as early as 4000 BC was called meteoric iron and was found on the surface of the Earth. This type of iron came from the meteorites that struck the Earth before humans appeared, and was in very limited supply. This type is unlike most of the iron in the Earth, as the iron in the Earth was much deeper than the humans of that time period were able to excavate. The nickel content of

2346-491: The meteoric iron made it not necessary to be heated up, and instead, it was hammered and shaped into tools and weapons. Iron ore can be found in a multitude of forms and sources. The primary forms of iron ore today are Hematite and Magnetite . While iron ore can be found throughout the world, only the deposits in the order of millions of tonnes are processed for industrial purposes. The top five exporters of Iron ore are Australia, Brazil, South Africa, Canada, and Ukraine. One of

2397-418: The need for standardized diagnostic criteria and severity grading systems to improve the accuracy of LFS diagnosis and treatment. Several species of the microbe genera Actinomycetes , Streptomyces , Nocardia , Micromonospora , and Actinoplanes are capable of consuming rubber latex. However, the rate of biodegradation is slow, and the growth of bacteria utilizing rubber as a sole carbon source

2448-537: The price of natural gas to increase by 50% in 2022. While pottery originated in many different points around the world, it is certain that it was brought to light mostly through the Neolithic Revolution . That is important because it was a way for the first agrarians to store and carry a surplus of supplies. While most jars and pots were fire-clay ceramics , Neolithic communities also created kilns that were able to fire such materials to remove most of

2499-404: The surprise was a transition with a decrease in temperature at around 260 K (−13 °C) to a phase with no net magnetic moment. It was shown that the system is essentially antiferromagnetic, but that the low symmetry of the cation sites allows spin–orbit coupling to cause canting of the moments when they are in the plane perpendicular to the c axis. The disappearance of the moment with

2550-498: The water and collect in layers at the bottom of the lake, spring, or other standing water. Hematite can also occur in the absence of water, usually as the result of volcanic activity. Clay -sized hematite crystals also may occur as a secondary mineral formed by weathering processes in soil , and along with other iron oxides or oxyhydroxides such as goethite , which is responsible for the red color of many tropical , ancient, or otherwise highly weathered soils. The name hematite

2601-611: Was favorable for life". Hematite is often shaped into beads, tumbling stones, and other jewellery components. Hematite was once used as mourning jewelry. Certain types of hematite- or iron-oxide-rich clay, especially Armenian bole , have been used in gilding . Hematite is also used in art such as in the creation of intaglio engraved gems . Hematine is a synthetic material sold as magnetic hematite . Hematite has been sourced to make pigments since earlier origins of human pictorial depictions, such as on cave linings and other surfaces, and has been employed continually in artwork through

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