Plants Plants The plant genus Abromeitiella has been deleted and its members have all been combined in the previously existing genus Deuterocohnia. The rationale for this combination was the analysis of the two genera and the conclusion that they were identical in all respects save the length of the floral scape (flower stalk or stem). ...more on Wikipedia about "Abromeitiella"
Acmena smithii (formerly Eugenia smithii) is a summer flowering evergreen tree, belonging to the myrtle family Myrtaceae. It is commonly planted as shrubs or hedgerows. It features rough woody bark, smooth waxy leaves and dark red berries. It shares the common name Lillipilli along with several other plants. ...more on Wikipedia about "Acmena smithii"
Agave eggersiana - endangered species of spiky plant - grows in the Virgin Islands. ...more on Wikipedia about "Agave eggersiana"
Anthocyanins (Etymology: greek. anthos = Flower, kyáneos = purple) are water soluble pigments that reflect the red to blue range of the visible spectrum. They are often observed in the plant kingdom, where they serve to color anything from fruits to the autumn leaves. These pigments act as powerful antioxidants helping to protect the plant from UV damage. They can be used as a pH indicator because they change from red in acids to blue in bases. Anthocyanins belong to a class of compounds called flavonoids. The anthocyanins ...more on Wikipedia about "Anthocyanin"
Anthophyta is a traditional botanical name that may be used (Art 16, ICBN) for what, these days, is more commonly known as Angiospermae. The name Anthophyta literally means " flowering plants"; derived from the greek 'anthos'="flower" and 'phyton'= "plant". ...more on Wikipedia about "Anthophyta"
Arctotheca calendula is a plant commonly known as 'cape weed', 'cape dandelion' or 'cape marigold' because it originates from the Cape Province in South Africa. It is listed as a noxious weed in California. ...more on Wikipedia about "Arctotheca calendula"
The Bach and Wheeler Bowel Nosodes, developed from bowel flora, were developed in the 1920s, by Dr. Edward Bach & Dr. Charles Wheeler (1868-1939). They were later elaborated further by Dr. John Paterson (1890 –1954). ...more on Wikipedia about "Bach nosodes"
The meaning of bane as an English form of nemesis, the bringer of ruin, dates only from 1577. Now an affliction, curse, evil, ill, plague, scourge or woe, in Old English bana had a more specific and immediate meaning, of "slayer", "murderer." ...more on Wikipedia about "Bane"
Betacyanin is the nitrogen-based red pigment of beets (Beta spp.) and other Chenopodiaceae. ...more on Wikipedia about "Betacyanin"
A Biennial plant is a plant that takes between twelve and twenty-four months to complete its lifecycle. In the first year the plant grows leaves and stems (vegetative structures) and then it enters a period of dormancy over the colder months. The next spring/summer it produces fruit, flowers and seeds, and then dies. ...more on Wikipedia about "Biennial plant"
Blossom is a term given to the flowers of stone fruit trees (Genus Prunus) and of some other plants with a similar appearance that flower profusely but for a short period of time. Blossoms are either pink or white depending on the species or variety. Nectarine blossoms, peach blossoms, most cherry blossoms, and some almond blossoms are usually pink. Plum blossoms, apple blossoms, some cherry blossoms, and most almond blossoms are white. ...more on Wikipedia about "Blossom"
Calotropis are a genus of plants that produce milky sap. It is considered a common weed in some parts of the world. The flowers are fragrant and are often used in making 'floral tassels' in some mainland Southeast Asian cultures. ...more on Wikipedia about "Calotropis"
A carnivorous plant is a plant that derives some or most of its ...more on Wikipedia about "Carnivorous plant"
Cavitation is the phenomenon where small cavities of partial vacuum form in fluid, then rapidly collapse, producing a sharp sound. Cavitation occurs in pumps, propellers, impellers, and the vascular tissues of plants. ==Overview== Cavitation is the formation of pockets of vapor in a liquid. This process is caused by low pressures in the liquid. When the local ambient pressure at a point in the liquid falls below the liquid's vapor pressure, the liquid undergoes a phase change to a gas, creating "bubbles," or, more accurately, cavities, in the liquid. The physical process of cavitation is almost exactly the same as that which occurs during boiling. The major difference between the two is how the phase change is affected. Boiling raises the vapor pressure of the liquid above its local ambient pressure to cause the phase change to a gas, whereas cavitation is caused by a drop of the local ambient pressure below the vapor pressure. In order for cavitation to occur, the cavitation "bubbles" need a surface on which to nucleate. This surface can be provided by the side of a container, impurities in the liquid, or other irregularities. Liquid temperature is a major factor in how much cavitation occurs. Changing temperatures alter the vapor pressure of a liquid dramatically, making it easier or harder for the local ambient pressure to dip below the vapor pressure to cause cavitation. ==Problems== Cavitation is, in many cases, an undesirable occurrence. In devices such as propellers and pumps, cavitation causes a great deal of noise, damage to components, and a loss of efficiency. When the "bubbles" of cavitation collapse, they create large amounts of noise. The noise created by cavitation is a particular problem in submarines, as the noise destroys its stealth. The collapse of cavities involves very high energies, and can cause major damage. Cavitation can damage almost any substance. The pitting caused by the collapse of cavities produces great wear on components and can dramatically shorten a propeller or pump's lifetime. Additionally, the creation of and subsequent collapse of cavitation bubbles creates friction and turbulence in the liquid. This contributes to a loss of efficiency in devices that are experiencing cavitation. ==Beneficial Uses== Although cavitation is undesirable in many circumstances, this is not always the case. For example, supercavitating torpedoes in use by the military envelope the torpedo in a large bubble of cavitation. By eliminating contact with water, and, therefore, eliminating the high drag of water, these torpedoes can move very fast underwater, perhaps even at supersonic speeds. Cavitation can also be a boon in ultrasonic cleaning devices. These devices affect cavitation using sound waves and use the collapse of the cavitation bubbles to clean surfaces. Used in this manner, the need for sometimes enviromentally harmful chemicals can be reduced in many industrial and commercial processes that require cleaning as a step. In industry, cavitation is often used to homogenize, or mix and break down suspended particles in a colloidal liquid compound, such as paint mixtures, or milk. Many industrial mixing machines are based upon this design principle. It is usually achieved through impeller design, or by forcing the mixture through an annular opening that has a narrow entrance orifice with a much larger exit orifice: the drastic decrease in pressure as the liquid accelerates into the larger volume causes cavitation to take place. This method can be controlled with hydraulic devices that control the size of the inlet orifice, and this allows for adjustment to the process "on the fly", or for different substances. The outer surface of this type of mixing valve, upon which the cavitation bubbles are driven against to cause their implosion, undergoes tremendous stress, and is often constructed of super-hard or tough materials such as stainless steel, Stellite, or even polycrystalline diamond (PCD). Cavitating water purification devices have also been designed, in which the extreme conditions of cavitation can break down pollutants and organic molecules. Analysis of sonochemistry show energy levels in sonoluminesence cavitation bubbles to be ideal for this type of chemical break down. ==Pumps and propellers== Major places where cavitation occurs are in pumps, on propellers, or at restrictions in a flowing liquid. As an impeller's (in a pump), or propeller's (as in the case of a ship or submarine) blades move through a fluid, low pressure areas are formed as the fluid accelerates around and moves past the blades. The faster the blades move, the lower the pressure around it can become. As it reaches vapor pressure, the fluid vaporizes and forms small bubbles of gas. This is cavitation. When the bubbles collapse later, they typically cause very strong local shockwaves in the fluid, which may be audible and may even damage the blades. Cavitation in pumps may occur in two different forms: ===Suction cavitation=== Suction cavitation occurs when the pump suction is under a low pressure/high vacuum condition where the liquid turns into a vapor at the eye of the pump impeller. This vapor is carried over to the discharge side of the pump where it no longer sees vacuum and is compressed back into a liquid by the discharge pressure. This imploding action occurs violently and attacks the face of the impeller. An impeller that has been operating under a suction cavitation condition has large chunks of material removed from its face causing premature failure of the pump. ===Discharge cavitation=== Discharge cavitation occurs when the pump discharge is extremely high. It normally occurs in a pump that is running at less than 10% of its best efficiency point. The high discharge pressure causes the majority of the fluid to circulate inside the pump instead of being allowed to flow out the discharge. As the liquid flows around the impeller it must pass through the small clearance between the impeller and the pump cutwater at extremely high velocity. This velocity causes a vacuum to develop at the cutwater (similar to what occurs in a venturi) which turns the liquid into a vapor. A pump that has been operating under these conditions shows premature wear of the impeller vane tips and the pump cutwater. In addition due to the high pressure condition premature failure of the pump mechanical seal and bearings can be expected. Under extreme conditions this can break the impeller shaft. Discharge cavitation is believed to be the cause of the cracking of joints. ==Vascular plants== Cavitation occurs in the xylem of vascular plants when the water potential becomes so great that dissolved air within the water expands to fill the plant cell - either vessel elements or tracheids. Plants are generally able to repair cavitated xylem, for example with root pressure, but for others such as vines, cavitation often leads to mortality. In some trees, the sound of the cavitation is clearly audible. ==See also== *The phenomenon known as supercavitation is used to allow objects to travel under water at high speed. * Supercavitating propeller * Sonoluminescence * Cavitation number ==External links== * Supercavitation * Cavitation vs. Supercavitation ==References== For cavitation in plants, see Plant Physiology, by Taiz and Zeiger. ...more on Wikipedia about "Cavitation"
(Cempasúchil) The Mexican marigold is a species of the genus Tagetes native to Mexico and Central America. In Mexico, this plant is found in the states of San Luis Potosí, Chiapas, State of México, Puebla, Sinaloa, Tlaxcala and Veracruz. This plant reaches heights of between 50 and 100 cm. ...more on Wikipedia about "Cempasúchil"
Chia Pets are a brand of collectible animal figurines manufactured and originated by the San Francisco, California based company Joseph Enterprises, Inc. Chia Pets achieved widespread popularity in the 1980s following the 1982 release of a ram, the first Chia Pet. Subsequent decline in popularity has relegated these objects to fad status. The catch-phrase related to the Chia Pet, sung in the commercial as the plant grows, is "Ch-ch-ch-chia!" ...more on Wikipedia about "Chia Pet"
The embryophytes are the most familiar group of plants, including trees, flowers, ferns, mosses, and various others. All are complex multicellular organisms with specialized reproductive organs and, with very few exceptions, they obtain their energy through photosynthesis, i.e. by absorbing light, and synthesize food from carbon dioxide. They may be distinguished from multicellular algae by having sterile tissue within the reproductive organs. Further, embryophytes are primarily adapted for life on land, although some are secondarily aquatic. Accordingly they are often called land plants. ...more on Wikipedia about "Embryophyte"
Erismanthus is a plant genus of the family Euphorbiaceae. It comprises 2 genera, found from Malesia to China. ...more on Wikipedia about "Erismanthus"
The flowering plants (also called angiosperms) are a major group of land plants. They comprise one of the two groups in the seed plants: the flowering plants cover their seeds by including them in a true fruit. They bear the reproductive organs in a structure called a flower; the ovule is enclosed within a carpel, which will lead to a fruit. ...more on Wikipedia about "Flowering plant"
Frankincense or olibanum is an aromatic resin obtained from the tree Boswellia thurifera or B. sacra, B. carterii ( Burseraceae). It is used in incense as well as in perfumes. ...more on Wikipedia about "Frankincense"
Grass generally describes a monocotyledonous green plant characterized by slender leaves, called blades, which usually grow arching upwards from the ground. Plants that are botanically regarded as "true" grasses fall into the flowering plant family, Poaceae. However, there are other plants outside this plant family that have similar appearance, and are commonly referred to as grasses, or have "grass" as part of their name. These include: ...more on Wikipedia about "Grass" Just shortopedia way
Greenery is generally used to describe any foliage of a plant, either live, freshly cut, or artificial. While this may be interpreted very literally to only mean green foliage, variegated foliage with other colours is often included as well. It usually does not include flowers. ...more on Wikipedia about "Greenery"
Groundcover is any plant used for the purpose of growing over an area of ground to hide it or to protect it from erosion or drought. In an ecosystem, the ground cover is the layer of vegetation below the shrub layer. ...more on Wikipedia about "Groundcover"
Guzmania is a genus of epiphytes. ...more on Wikipedia about "Guzmania"
Gymnosperms (Gymnospermae) is a name for a group of seed-bearing (and thus vascular) plants. The term gymnosperm comes from the Greek word gumnospermos, literally meaning "naked seed": this is because the seeds of these plants are not formed in an ovule that is enclosed (and developing into a fruit, in the angiosperms), but naked on the scales of a cone or cone-like structure. ...more on Wikipedia about "Gymnosperm"
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