Factbites
 Where results make sense
About us   |   Why use us?   |   Reviews   |   PR   |   Contact us  

Topic: Arsenates


In the News (Wed 19 Jun 19)

  
  Chapter 25. Arsenates, arsenites, phosphates, and vanadates
Although the number of arsenate, arsenite, phosphate, and vanadate species is second only to that of the silicates, specimens are for the most part rare, and many exceedingly so.
These species are almost entirely arsenates except magnussonite, nelenite, and schallerite, which are vein-filling arsenites; pyrobelonite and descloizite, which are the only known local vanadate minerals; and three anomalous and aberrant phosphates, meta-ankoleite, newberyite, and niahite.
The preponderance of the Sterling Hill arsenates are associated with zincite-bearing ore, the red-willemite ore of Parker and Troy (1982), in which no arsenic-bearing primary mineral is found; arsenic may have been introduced to this ore from the fl- willemite zone, the enclosing marble, or some other source.
franklin-sterlinghill.com /dunn/ch25/arsenates.stm   (533 words)

  
 Mineral Gallery - The Phosphate Subclasses
The Arsenate, Vanadate and Antimonate Subclasses of the Phosphate Class of Minerals
The Arsenate subclass, and to a lesser extent the Vanadate Subclass, of the Phosphate Class almost perfectly mirrors the true phosphates in many ways including structure, diversity and properties.
The only major difference is the arsenate or vanadate ion replacing the phosphate ion.
mineral.galleries.com /minerals/phosphat/arsenate.htm   (135 words)

  
  Chapter 25. Arsenates, arsenites, phosphates, and vanadates
Although the number of arsenate, arsenite, phosphate, and vanadate species is second only to that of the silicates, specimens are for the most part rare, and many exceedingly so.
These species are almost entirely arsenates except magnussonite, nelenite, and schallerite, which are vein-filling arsenites; pyrobelonite and descloizite, which are the only known local vanadate minerals; and three anomalous and aberrant phosphates, meta-ankoleite, newberyite, and niahite.
The preponderance of the Sterling Hill arsenates are associated with zincite-bearing ore, the red-willemite ore of Parker and Troy (1982), in which no arsenic-bearing primary mineral is found; arsenic may have been introduced to this ore from the fl- willemite zone, the enclosing marble, or some other source.
www.simplethinking.com /dunn/ch25/arsenates.stm   (533 words)

  
 AsRT Brochure
Laboratory Experiment #1: Arsenate adsorption isotherm experiments were conducted using saturated zone sand taken from the vicinity of a landfill in Maine USA and iron filings to examine arsenate immobilization.
The solutions of different arsenate concentrations were prepared by adding an appropriate quantity of sodium arsenate stock solution to the constant ionic strength solution.
To evaluate the impact of iron filings on the immobilization the arsenate alone, we conducted a control experiment that was exactly the same as the one described above, only excluding the iron filings.
www.eng2.uconn.edu /~nikos/asrt-brochure.html   (2017 words)

  
 Arsenic Poisoning
The problem is that when you use arsenate instead of organic phosphate, you don't get any ATP when 3-phosphoglycerate is produced.
I'll betcha this is where the arsenate is causing all the trouble (though I can't find this specifically in a book).
It is no use except early in the course of the disease because the arsenates have been taken up by tissue.
www.vin.com /vin_ce/abvp/html/arsenic_poisoning.html   (375 words)

  
 Mineralogy - Phosphates, Vanadates and Arsenates   (Site not responding. Last check: )
Adamite is a favorite among collectors of fluorescent minerals because of its consistent bright green fluorescence under short and long UV light.
Erythrite, of whom roselite is often associated, is also a rose-colored cobalt arsenate and is easily confused with roselite except for the micaceous cleavage of erythrite.
Although, a serious collector might not admit it, the more valuable specimens are those that are predominantly pristine, uncleaved clusters with at least a few cleaved globules to demonstrate the light play.
l2l.port5.com /s_geol/mnr_phos.html   (2150 words)

  
 Berzelian Classification System
The arsenates and vanadates are closely akin to the phosphates.
Section 5.) Sulfides and arsenides are frequently altered to produce the secondary sulfates and arsenates.
Pyromorphite is thus a phosphate, mimetite is an arsenate, and vanadinite is a vanadate.
dave.ucsc.edu /myrtreia/Berzelian_class.html   (7720 words)

  
 Index of phosphates (arsenates and vanadates).
This is the list of the phosphates (arsenates and vanadates) class.
This is not a list of my collection, it's a list of mineral descriptions, mainly Swedish.
If you have some questions, suggestions or comments you are welcome to write me a line or two.
www.geology.neab.net /minerals/indxphos.htm   (77 words)

  
 Arsenic: United States
Ammoniacal Copper Zinc Arsenate (ACZA) is a very similar arsenic formulation sold primarily on the West coast as Chemonite.
Toxicity from natural sources of arsenic is rare except from drinking highly contaminated groundwater or from breathing highly contaminated air (e.g., from burning of arsenic-containing coal indoors without adequate ventilation).
Other inorganic forms of arsenic called arsenates are in the pentavalent state (As5+) and are several times less toxic than the arsenites.
www.lycos.com /info/arsenic--united-states.html   (715 words)

  
 Arsenic Trifluoride. TOXNET profile from Hazardous Substances Data Bank.k.
The effect of phosphates, arsenates, and arsenites on the growth of the As-oxidizing microorganisms Pseudomonas putida and Alcaligenes eutrophus was studied in the presence of yeast extract, glucose, fish peptone agar, sodium citrate, sodium acetate, and sodium lactate.
The distribution of 74-As-labeled arsenate and arsenite in pregnant mice and a monkey has been studied by autoradiography and gamma counting of isolated tissues, and their in vitro toxicity to a chondrogenic system has been investigated.
Aquatic: Total As, arsenate and arsenite concn profiles for the water column of Saanich Inlet, an intermittently anoxic fjord located on Vancouver Island, B.C., Canada, were measured using independent analytical techniques for total As and As speciation to evaluate the accuracy of the speciation technique in oxic and anoxic marine environments.
www.fluoridealert.org /pesticides/arsenic.trifluoride.toxnet.htm   (9804 words)

  
 arsenic_annex2
Various salts (arsenates) are derived from arsenic acid, and are described in detail below.
Arsenates are oxidising agents and are reduced with concentrated hydrochloric acid or sulphur dioxide.
Arsenates of calcium or lead are often used as insecticides.
www.aeat.co.uk /netcen/airqual/reports/arsenic00/arsenic_annex2.htm   (1733 words)

  
 Fahlerz and Arsenic-bearing
However, it should be stressed that the replacement of earlier minerals by tetrahedrite is part of the primary mineralisation and not part of the later processes of supergene enrichment or weathering, as widely reported in the archaeological literature (Craddock, 1995).
Typically these copper-arsenic-bearing secondary minerals are brightly coloured and found in minor to trace amounts in the upper oxidised zones (gossans) of arsenical copper deposits, or even on mine spoil, having formed as part of their post-mining oxidation by local groundwaters.
However, the greatest concentration of copper and copper-bearing arsenates is reported from Devon and Cornwall (Embrey and Symes, 1987), where locally, as for example at Wheal Gorland in the St Day district of central Cornwall, the mine dumps are well known for their arsenate assemblages (C. Stanley, pers.comm.).
www.rosiehardman.com /fahlerz.htm   (7179 words)

  
 [No title]
It is sometimes necessary to pre-oxidize any arsenites present to arsenates in order to effectively remove arsenic from drinking water to safe levels.
The rate of arsenites oxidation to form arsenates is therefore limited in the case of oxygen by the rate of oxygen dissolving in the drinking water to be treated.
Adsorption media may also be used in combination with oxidants such as manganese compounds to pre-oxidize any arsenites present to arsenates which are more efficiently adsorbed from the contaminated water.
www.developmentgateway.org /environment/rc/filedownload.do~itemId=1060999?itemId=1060999   (2186 words)

  
 [No title]   (Site not responding. Last check: )
In comparison with the rich structural chemistry of transition metal phosphates, reports on the arsenates are rare.
Recently we have investigated the structural chemistry of transition metal arsenates and have synthesized a number of new compounds in the A-M-As -O system (A = alkali or alkaline-earth metals and M = V, Fe, Co, Ni, Cu, and Mo) by using hydrothermal methods.
Most of these arsenates adopt new structural types and have stoichiometries not found in the phosphates.
www.iucr.org /iucr-top/cong/17/iucr/abstracts/abstracts/S0599.html   (220 words)

  
 Secondary minerals of the Mazarron-Aguilas, Mining District, Murcia Province, Spain Mineralogical Record - Find Articles   (Site not responding. Last check: )
Outstanding among these are the new mineral cobaltarthurite for which the Dolores prospect is the type locality, world-class specimens of lavendulan, one of the first world occurrences of zalesiite, rare yukonite specimens and, perhaps, some future new mineral species currently under study.
Its habit, color and association with other copper arsenates suggested that the specimen could be lavendulan, and an EDS qualitative analysis at the Mining School of Madrid in 1992 confirmed the identification.
Investigations of other copper prospects in the area were conducted, and one small prospect in the Umbria de Ramonete valley was found also to produce lavendulan, as small electric-blue crystals similar to the Dolores specimens.
www.findarticles.com /p/articles/mi_qa3672/is_200307/ai_n9279671   (897 words)

  
 Secondary minerals of the Mazarron-Aguilas, Mining District, Murcia Province, Spain Mineralogical Record - Find Articles
Outstanding among these are the new mineral cobaltarthurite for which the Dolores prospect is the type locality, world-class specimens of lavendulan, one of the first world occurrences of zalesiite, rare yukonite specimens and, perhaps, some future new mineral species currently under study.
Its habit, color and association with other copper arsenates suggested that the specimen could be lavendulan, and an EDS qualitative analysis at the Mining School of Madrid in 1992 confirmed the identification.
Investigations of other copper prospects in the area were conducted, and one small prospect in the Umbria de Ramonete valley was found also to produce lavendulan, as small electric-blue crystals similar to the Dolores specimens.
findarticles.com /p/articles/mi_qa3672/is_200307/ai_n9279671   (880 words)

  
 Human Health Hazards -- Lead Arsenate Pesticides
One, a lead arsenate based pesticide, was used extensively to control agricultural pests in fruit orchards until the late 1950s.
Exposure to lead arsenate pesticides in former orchard soils involves contact with the bare soils.
In many orchards there was an area used to mix the lead arsenate pesticides with water and loaded into sprayers.
www.dhfs.state.wi.us /eh/HlthHaz/fs/LeadArPest.htm   (799 words)

  
 Attack of the Rock-Eating Microbes!: Science News Online, Nov. 15, 2003   (Site not responding. Last check: )
Evidence is now mounting that organic matter and the microbes it feeds may be playing a role in the formation of arsenites in aquifers.
Part of the solution to this arsenic problem may be to nurture soil microbes that would lock down arsenic compounds instead of releasing them.
The result suggests the presence of a thriving community of anaerobic microbes that used the nitrates as fuel and converted the poisonous arsenites in the water to less-soluble arsenates.
www.sciencenews.org /articles/20031115/bob9.asp   (2315 words)

  
 QUT | ePrints Archive - Raman spectroscopy of the arsenates and sulphates of the tsumcorite mineral group
Raman spectroscopy of the arsenates and sulphates of the tsumcorite mineral group
Frost, Ray L. and Kloprogge, J. Theo and Martens, Wayde N. Raman spectroscopy of the arsenates and sulphates of the tsumcorite mineral group .
The position of the hydroxyl and water stretching vibrations are related to the strength of the hydrogen bond formed between the OH unit and the AsO4 anion. Estimates of the hydrogen bond distances are calculkated using a Libowitzky type function.
eprints.qut.edu.au /archive/00000816   (183 words)

  
 The formation of mineral arsenates in wastewaters
Recently determined thermodynamic constants (1) suggest that most arsenate minerals may be more insoluble than previously reported, with tin arsenate found to be the least soluble of all the metal arsenates studied (k
Itis conceivable that the precipitation of arsenate minerals in wastewater plays an important role in the removal of both arsenate and heavy metals from municipal wastewater systems.
The removal of arsenate from water and wastewater by tin treatment is also discussed.
www.edpsciences.org /articles/jp4/abs/2003/05/jp4pr5p0753/jp4pr5p0753.html   (236 words)

  
 January 2001: Ferric salts reduce arsenic in mine effluent by combining chemical and biological treatment
Arsenite-containing effluent is generally oxidized prior to precipitation to ensure that the arsenate predominates.
Thus, where ferric arsenate is relatively soluble, the basic arsenates with an iron-to-arsenic molar ratio of eight or more are orders of magnitude less soluble in the pH range of approximately 2 to 8.
The precipitation of insoluble ferric arsenates is very likely accompanied by co-precipitation of other metals such as selenium; that involves interactions between the various metals species and the ferric hydroxide precipitate.
www.esemag.com /0101/ferric.html   (1187 words)

  
 EPA: ORD: NCER: Advanced Search
Also, both As(III) and As(V), referred to as arsenites and arsenates, may be present simultaneously in groundwater.
Arsenic concentration in the treated water should remain less than 10 µg/L independent of any fluctuations of arsenic concentrations and relative distribution of arsenites and arsenates in groundwater.
The development of MNZ provides a desirable synergy: while the zeolite provides favorable hydraulic properties in a fixed-bed column, HFO particles are the active ingredients for selective sorption of arsenites and arsenates.
cfpub.epa.gov /ncer_abstracts/index.cfm/fuseaction/display.abstractDetail/abstract/6317/report/0   (564 words)

  
 Arsenic
ARSENIC, As The order of decreasing toxicity (most to least) for arsenic is: arsines, inorganic arsenites, organic arsenoxides, inorganic arsenates, arsenorganics with As valence of +5, and metallic As.
Insecticides, rodenticides and fungicides (Na-, K- arsenites, arsenates, also oxides are commercially available).
Commercial arsenic products include: sodium arsenite, calcium arsenate, lead arsenate and "Paris green" (cupric acetoarsenite) a wood preservative.
drkaslow.com /html/arsenic.html   (879 words)

  
 658. Arsenic (WHO Food Additives Series 24)
While arsenic can be found to a small extent in the elemental form, the most important inorganic arsenic compounds are arsenic trioxide, sodium arsenite, arsenic trichloride (i.e.
In addition to arsenic from air, water and food, tobacco treated with arsenate sprays may also be a route of exposure for those persons who are smokers.
In summary, the intake of arsenic from air, excluding industrial areas, is a minor portion of the total intake from all sources.
www.inchem.org /documents/jecfa/jecmono/v024je08.htm   (2118 words)

  
 Arsenic
ARSENIC, As The order of decreasing toxicity (most to least) for arsenic is: arsines, inorganic arsenites, organic arsenoxides, inorganic arsenates, arsenorganics with As valence of +5, and metallic As.
Insecticides, rodenticides and fungicides (Na-, K- arsenites, arsenates, also oxides are commercially available).
Commercial arsenic products include: sodium arsenite, calcium arsenate, lead arsenate and "Paris green" (cupric acetoarsenite) a wood preservative.
www.drkaslow.com /html/arsenic.html   (879 words)

  
 Earth Science World Image Bank
Amorphous Aggregate; Arsenates; Hydrated Iron Oxides; Hydrated Phosphates; Hydroxides; Legrandite; Mineralogy; Monoclinic; Oxides; Phosphates; Secondary Mineral; Vanadates
Arsenates; Hydrated Aluminum Phosphate; Hydrothermal Mineral; Mineralogy; Orthorhombic; Phosphates; Secondary Mineral; Spherulitic; Vanadates
Arsenates; Brazilianite; Gems; Hydrous Sodium Aluminum Phosphate; Mineralogy; Monoclinic; Phosphates; Vanadates
www.earthscienceworld.org /images/search/results.html?Keyword=Vanadates   (155 words)

  
 Planner updates playground status - The Boston Globe
Soil testing done to be sure that the old play structure did not leach arsenates into...
Soil testing done to be sure that the old play structure did not leach arsenates into the soil has had good results.
New playground equipment was ordered on July 23, thanks to a last minute donation from Tabor Academy to pay for the new large toddler climbing structure.
www.boston.com /news/local/articles/2004/08/05/planner_updates_playground_status   (230 words)

  
 Synthesis and Characterization of Four Ethylenediamine-Templated Iron Arsenates
Synthesis and Characterization of Four Ethylenediamine-Templated Iron Arsenates
Four new ethylenediamine-templated iron arsenates and fluoroarsenates have been hydrothermally synthesized from iron metal, hydrofluoric and arsenic acids, and ethylenediamine.
(4) are an arsenate and a fluoroarsenate, respectively, with three-dimensional open-framework type structures.
pubs.acs.org /cgi-bin/abstract.cgi/inocaj/2000/39/i11/abs/ic991367b.html   (257 words)

  
 StockHouse.ca : BullBoards Postings - about uranium from alphatrack.ca
Hexavalent uranium forms a complex uranyl ion (UO2)+2 which combines with other elements, as oxides, silicates, sulfates, vanadates, arsenates, carbonates, phosphates and molybdates.
Uranium minerals can be categorized according to their predominant chemical composition, as oxides, silicates, vanadates, phosphates, sulfates, carbonates, arsenates, molybdates, selenites, tellurites, multiple oxides of niobates-tantalates-titantates and urano-organic complexes.
All uranyl arsenates are secondary minerals, derived from alteration of arsenides and uraninites.
www.stockhouse.ca /bullboards/viewmessage.asp?no=14022166   (2831 words)

Try your search on: Qwika (all wikis)

Factbites
  About us   |   Why use us?   |   Reviews   |   Press   |   Contact us  
Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.