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The metals are held together by metallic bonding, which confers distinctive physical properties such as their shiny metallic lustre, ductility and malleability, and electrical conductivity. Skinner expanded the previous definition of a mineral to classify "element or compound, amorphous or crystalline, formed through biogeochemical processes," as a mineral. The parenchyma of an organ consists of that tissue which conducts the specific function of the organ and which usually comprises the bulk of the organ. Such environmental problems prove the vital roles these wetlands play. See product defined for English-language learners.
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There are multiple methods for stabilizing suspensions, including electrostatics and sterics. In an unstable suspension, the dispersed, particulate phase will come out of solution in response to forces acting upon the particles, such as gravity or Hamaker attraction.
The magnitude of the effect these forces have on pulling the particulate phase out of solution is proportional to the size of the particulates; for a large particulate, the gravitational forces are greater than the particle-particle interactions, whereas the opposite is true for small particulates.
Shear thickening behavior is typically observed in suspensions of small, solid particulates, indicating that the particle-particle Hamaker attraction is the dominant force.
Therefore, stabilizing a suspension is dependent upon introducing a counteractive repulsive force. Hamaker theory describes the attraction between bodies, such as particulates. It was realized that the explanation of Van der Waals forces could be upscaled from explaining the interaction between two molecules with induced dipoles to macro-scale bodies by summing all the intermolecular forces between the bodies.
Similar to Van der Waals forces, Hamaker theory describes the magnitude of the particle-particle interaction as inversely proportional to the square of the distance. Therefore, many stabilized suspensions incorporate a long-range repulsive force that is dominant over Hamaker attraction when the interacting bodies are at a sufficient distance, effectively preventing the bodies from approaching one another.
However, at short distances, the Hamaker attraction dominates, causing the particulates to coagulate and fall out of solution. Two common long-range forces used in stabilizing suspensions are electrostatics and sterics. Suspensions of similarly charged particles dispersed in a liquid electrolyte are stabilized through an effect described by the Helmholtz double layer model. The model has two layers. The first layer is the charged surface of the particle, which creates an electrostatic field that affects the ions in the electrolyte.
In response, the ions create a diffuse layer of equal and opposite charge, effectively rendering the surface charge neutral. However, the diffuse layer creates a potential surrounding the particle that differs from the bulk electrolyte. The diffuse layer serves as the long-range force for stabilization of the particles.
When particles near one another, the diffuse layer of one particle overlaps with that of the other particle, generating a repulsive force. The following equation provides the energy between two colloids as a result of the Hamaker interactions and electrostatic repulsion. Different from electrostatics, sterically stabilized suspensions rely on the physical interaction of polymer chains attached to the surface of the particles to keep the suspension stabilized; the adsorbed polymer chains act as a spacer to keep the suspended particles separated at a sufficient distance to prevent the Hamaker attraction from dominating and pulling the particles out of suspension.
The polymers are typically either grafted or adsorbed onto the surface of the particle. With grafted polymers, the backbone of the polymer chain is covalently bonded to the particle surface. Whereas an adsorbed polymer is a copolymer composed of lyophobic and lyophilic region, where the lyophobic region non-covalently adheres to the particle surface and the lyophilic region forms the steric boundary or spacer.
Dilatancy in a colloid, or its ability to order in the presence of shear forces is dependent on the ratio of interparticle forces. As long as interparticle forces such as Van der Waals forces dominate, the suspended particles remain in ordered layers. However, once shear forces dominate, particles enter a state of flocculation and are no longer held in suspension; they begin to behave like a solid.
When the shear forces are removed, the particles spread apart and once again form a stable suspension. This is opposite of the shear thinning effect where the suspension is initially in the state of flocculation and becomes stable when a stress is applied.
Shear thickening behavior is highly dependent upon the volume fraction of solid particulate suspended within the liquid. The higher the volume fraction, the less shear required to initiate the shear thickening behavior.
The shear rate at which the fluid transitions from a Newtonian flow to a shear thickening behavior is known as the critical shear rate. When shearing a concentrated stabilized solution at a relatively low shear rate, the repulsive particle-particle interactions keep the particles in an ordered, layered, equilibrium structure. However, at shear rates elevated above the critical shear rate, the shear forces pushing the particles together overcome the repulsive particle-particle interactions, forcing the particles out of their equilibrium positions.
This leads to a disordered structure, causing an increase in viscosity. The critical shear rate here is defined as the shear rate at which the shear forces pushing the particles together are equivalent to the repulsive particle interactions. When the particles of a stabilized suspension transition from an immobile state to mobile state, small groupings of particles form hydroclusters, increasing the viscosity. Fortified wines may be dry or sweet.
If alcohol is added early during the wine fermentation, it will kill yeasts and thus prevent conversion of the remaining sugar to alcohol, so the resulting wine will be sweet. Examples of fortified wines:. Aperitifs have bittersweet taste. Yeasts, naturally present in apples, convert sugars from apple juice into alcohol and carbon dioxide. Cider may be dry or sweet, still or sparkling. Examples of cider related drinks are perry from pears , rhubarb and quince cider. Spirits categorization, according to the U.
Certain brandies are flavored with fruits or herbs or sweetened with sugar. Pomace brandy is produced by distillation of grape pomace, that is pressed solid parts skins, pulp, seeds, stems left after wine-making process .
Fruit brandy is a general term for brandies distilled from fruit wines except grape wines or fermented berries . Examples of fruit brandies:. Neutral spirits have no color, distinct taste or odor. Domestic spirit production is illegal in many, but not all, countries. Certain moonshine beverages may contain dangerous ingredients, such as methanol or heavy metals. Examples of moonshines by country:. According to the U.
Subyou is a powdered alcohol intended to add to soft drinks; it was once popular in Germany . They often come in large List of caffeinated alcoholic beverages. Some producers have stopped adding caffeine to alcohol beverages after FDA sent them warning letters in November Currently, in the U.
Producers claim that the use of the AWOL machine leads to intoxication 10 times faster than regular drinking and does not cause hangover because it does not contain carbohydrates and other congeners.
Such waste could be inflammable can easily catch fire , reactive can easily explode , corrosive can easily eat through metal or toxic poisonous to human and animals. In many countries, it is required by law to involve the appropriate authority to supervise the disposal of such hazardous waste.
Examples include fire extinguishers, old propane tanks, pesticides, mercury-containing equipment e. More on hazardous waste here. Organic waste comes from plants or animals sources. Commonly, they include food waste, fruit and vegetable peels, flower trimmings and even dog poop can be classified as organic waste. They are biodegradable this means they are easily broken down by other organisms over time and turned into manure.
Many people turn their organic waste into compost and use them in their gardens.