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25-978: Oros may refer to: OROS , drug delivery system Oros, Sindhudurg , town in India Orós , municipality in Ceará, Brazil People [ edit ] Oros of Alexandria , 5th century Byzantine lexicographer and grammarian Corneliu Oros (born 1950), Romanian former volleyball player Cristian Oroș (born 1984), Romanian football player Ernest L. Oros (died 2012), American politician from New Jersey George Oros (born 1954), American lawyer and politician from New York Joe Oros (1916–2012), American automotive designer Petro Oros (1917–1953) Ukrainian clandestine Greek-Catholic bishop Rozalia Oros (born 1964), Romanian fencer Yaroslav Oros (born 1959) Ukrainian writer and journalist See also [ edit ] Oro (disambiguation) Topics referred to by

50-401: A reagent , heat, or simply washing with water. A summary of various leaching processes and their respective laboratory tests can be viewed in the following table: Some recent work has been done to see if organic acids can be used to leach lithium and cobalt from spent batteries with some success. Experiments performed with varying temperatures and concentrations of malic acid show that

75-464: A wastewater product/ raw materials. In the field of mineralogy, acid leaching is common to extract Metals such as vanadium, Cobalt, Nickel, Manganese, Iron etc. from raw materials/ reused materials. In recent years, there has been more attention given to metal leaching to recover precious metals from waste materials. For example, the extraction of valuable metals from wastewater. Due to the assortment of leaching processes there are many variations in

100-676: Is a naturally occurring process which scientists have adapted for a variety of applications with a variety of methods. Specific extraction methods depend on the soluble characteristics relative to the sorbent material such as concentration, distribution, nature, and size. Leaching can occur naturally seen from plant substances (inorganic and organic), solute leaching in soil, and in the decomposition of organic materials. Leaching can also be applied affectedly to enhance water quality and contaminant removal, as well as for disposal of hazardous waste products such as fly ash , or rare earth elements (REEs). Understanding leaching characteristics

125-406: Is controlled largely by the hydraulic conductivity of the soil, which is dependent on particle size and relative density that the soil has been consolidated to via stress. Diffusion is controlled by other factors such as pore size and soil skeleton, tortuosity of flow path, and distribution of the solvent (water) and solutes. Leaching can sometimes be used to extract valuable materials from

150-743: Is different from Wikidata All article disambiguation pages All disambiguation pages OROS Osmotic release systems have a number of major advantages over other controlled-release mechanisms. They are significantly less affected by factors such as pH , food intake, GI motility , and differing intestinal environments. Using an osmotic pump to deliver drugs has additional inherent advantages regarding control over drug delivery rates. This allows for much more precise drug delivery over an extended period of time, which results in much more predictable pharmacokinetics . However, osmotic release systems are relatively complicated, somewhat difficult to manufacture, and may cause irritation or even blockage of

175-404: Is highly dependent on the characteristics of the soil, which makes modeling efforts difficult. Most leaching comes from infiltration of water, a washing effect much like that described for the leaching process of biological substances. The leaching is typically described by solute transport models, such as Darcy's Law , mass flow expressions, and diffusion -dispersion understandings. Leaching

200-541: Is if pesticides are leached and carried through stormwater runoff ,; this is not only necessary to plant health, but it is important to control because pesticides can be toxic to human and animal health. Bioleaching is a term that describes the removal of metal cations from insoluble ores by biological oxidation and complexation processes. This process is done in most part to extract copper , cobalt , nickel , zinc , and uranium from insoluble sulfides or oxides . Bioleaching processes can also be used in

225-484: Is important in preventing or encouraging the leaching process and preparing for it in the case where it is inevitable. In an ideal leaching equilibrium stage, all the solute is dissolved by the solvent, leaving the carrier of the solute unchanged. The process of leaching however is not always ideal, and can be quite complex to understand and replicate, and often different methodologies will produce different results. There are many types of leaching scenarios; therefore,

250-571: The GI tract due to prolonged release of irritating drugs from the non-deformable tablet. The Elementary Osmotic Pump (EOP) was developed by ALZA in 1974, and was the first practical example of an osmotic pump based drug release system for oral use. It was introduced to the market in the early 1980s in Osmosin ( indomethacin ) and Acutrim ( phenylpropanolamine ), but unexpectedly severe issues with GI irritation and cases of GI perforation led to

275-649: The OROS technology. Multiple candidate pharmacokinetic profiles were evaluated and tested in an attempt to determine the optimal way to deliver the drug, which was especially important given the puzzling failure of an existing extended-release formulation of methylphenidate (Ritalin SR) to act as expected. The zero-order (flat) release profile that the PPOP was optimal at delivering failed to maintain its efficacy over time, which suggested that acute tolerance to methylphenidate formed over

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300-590: The course of the day. This explained why Ritalin SR was inferior to twice-daily Ritalin IR, and led to the hypothesis that an ascending pattern of drug delivery was necessary to maintain clinical effect. Trials designed to test this hypothesis were successful, and ALZA subsequently developed a modified PPOP design that utilized an overcoat of methylphenidate designed to release immediately and rapidly raise serum levels, followed by 10 hours of first-order (ascending) drug delivery from

325-423: The data to be collected through laboratory methods and modeling, making it hard to interpret the data itself. Not only is the specified leaching process important, but also the focus of the experimentation itself. For instance, the focus could be directed toward mechanisms causing leaching, mineralogy as a group or individually, or the solvent that causes leaching. Most tests are done by evaluating mass loss due to

350-512: The drug layer (which incorporates a viscous polymer for suspension of poorly soluble drugs) out of the exit hole at a controlled rate. Osmotic agents such as sodium chloride , potassium chloride , or xylitol are added to both the drug and push layers to increase the osmotic pressure . The initial design developed in 1982 by ALZA researchers was designated the Push-Pull Osmotic Pump (PPOP), and Procardia XL ( nifedipine )

375-413: The extent of this topic is vast. In general, however, the three substances can be described as: Substance A and B are somewhat homogenous in a system prior to the introduction of substance C. At the beginning of the leaching process, substance C will work at dissolving the surficial substance B at a fairly high rate. The rate of dissolution will decrease substantially once it needs to penetrate through

400-604: The material, the solvent, and their availability. These specific properties can include, but are not limited to: The general process is typically broken up and summarized into three parts: Biological substances can experience leaching themselves, as well as be used for leaching as part of the solvent substance to recover heavy metals . Many plants experience leaching of phenolics, carbohydrates , and amino acids , and can experience as much as 30% mass loss from leaching, just from sources of water such as rain , dew , mist , and fog . These sources of water would be considered

425-496: The modified PPOP design. This design was called the Push-Stick Osmotic Pump (PSOP), and utilized two separate drug layers with different concentrations of methylphenidate in addition to the (now quite robust) push layer. OROS medications include: Leaching (chemistry) Leaching is the process of a solute becoming detached or extracted from its carrier substance by way of a solvent . Leaching

450-416: The pores of substance A in order to continue targeting substance B. This penetration can often lead to dissolution of substance A, or the product of more than one solute, both unsatisfactory if specific leaching is desired. The physiochemical and biological properties of the carrier and solute should be considered when observing the leaching process , and certain properties may be more important depending on

475-556: The re-use of fly ash by recovering aluminum using sulfuric acid . Coal fly ash is a product that experiences heavy amounts of leaching during disposal. Though the re-use of fly ash in other materials such as concrete and bricks is encouraged, still much of it in the United States is disposed of in holding ponds, lagoons , landfills , and slag heaps. These disposal sites all contain water where washing effects can cause leaching of many different major elements , depending on

500-528: The same term [REDACTED] This disambiguation page lists articles associated with the title Oros . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Oros&oldid=1000987390 " Categories : Disambiguation pages Disambiguation pages with surname-holder lists Place name disambiguation pages Romanian-language surnames Hidden categories: Short description

525-458: The solvent in the leaching process and can also lead to the leaching of organic nutrients from plants such as free sugars , pectic substances, and sugar alcohols . This can in turn lead to more diversity in plant species that may experience a more direct access to water. This type of leaching can often lead to the removal of an undesirable component from the solid by water, this process is called washing. A major concern for leaching of plants,

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550-599: The type of fly ash and the location where it originated. The leaching of fly ash is only concerning if the fly ash has not been disposed of properly, such as in the case of the Kingston Fossil Plant in Roane County , Tennessee. The Tennessee Valley Authority Kingston Fossil Plant structural failure lead to massive destruction throughout the area and serious levels of contamination downstream to both Emory River and Clinch River . Leaching in soil

575-591: The withdrawal of Osmosin. Merck & Co. later developed the Controlled-Porosity Osmotic Pump (CPOP) with the intention of addressing some of the issues that led to Osmosin's withdrawal via a new approach to the final stage of the release mechanism. Unlike the EOP, the CPOP had no pre-formed hole in the outer shell for the drug to be expelled out of. Instead, the CPOP's semipermeable membrane

600-539: Was designed to form numerous small pores upon contact with water through which the drug would be expelled via osmotic pressure. The pores were formed via the use of a pH insensitive leachable or dissolvable additive such as sorbitol . Both the EOP and CPOP were relatively simple designs, and were limited by their inability to deliver poorly soluble drugs. This led to the development of an additional internal "push layer" composed of material (a swellable polymer ) that would expand as it absorbed water, which then pushed

625-412: Was one of the first drugs to utilize this PPOP design. In the early 1990s, an ALZA-funded research program began to develop a new dosage form of methylphenidate for the treatment of children with attention deficit hyperactivity disorder (ADHD). Methylphenidate's short half-life required multiple doses to be administered each day to attain long-lasting coverage, which made it an ideal candidate for

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