Off the Charts
US Release Cover
Studio album by The Briefs
Released	2003
Genre	Punk rock
Label	Dirtnap Records
The Briefs chronology
Hit After Hit (2000) Off the Charts (2003) Sex Objects (2004)
Alternate cover
UK Release Cover

Off the Charts is the second full album by The Briefs, released in both the US and the UK in 2003 on CD, and gatefold and white vinyl. The song “(Looking Through) Gary Glitter’s Eyes” is a nod to a song by The Adverts entitled “Gary Gilmore’s Eyes”.

phone lcd

St. Marguerite d’Youville Catholic Elementary School

Jump to: navigation, search

St. Marguerite d’Youville School is an elementary school (grades JK to Grade in the Halton Catholic District School Board. It opened in 1993 and celebrated its 10th anniversary in 2003 with a barbecue. It is now a feeding school for the high school, Holy Trinity Catholic Secondary School. It also houses French Immersion for students interested. In Grade 8, students go to Camp Brebeuf in October to prepare for their upcoming Confirmation. They also go on an end of year trip to the nation’s capital, Ottawa.

The school is named after Saint Marie-Marguerite d’Youville, the first Canadian-born saint and a member of the Canadian Medical Hall of Fame.

This Ontario school-related article is a stub. You can help Wikipedia by expanding it.

Retrieved from “http://en.wikipedia.org/wiki/St._Marguerite_d%27Youville_Catholic_Elementary_School”
Categories: Elementary schools in Oakville, Ontario | Educational institutions established in 1993 | Roman Catholic elementary schools in Canada | Ontario school stubs

Views

• Article
• Discussion
• Edit this page
• History

Personal tools

• Log in / create account

Navigation

• Main page
• Contents
• Featured content
• Current events
• Random article

Search

Interaction

• About Wikipedia
• Community portal
• Recent changes
• Contact Wikipedia
• Donate to Wikipedia
• Help

Toolbox

• What links here
• Related changes
• Upload file
• Special pages
• Printable version
• Permanent link
• Cite this page

• This page was last modified on 19 November 2008, at 05:38.
• All text is available under the terms of the GNU Free Documentation License. (See Copyrights for details.)
  Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a U.S. registered 501(c)(3) tax-deductible nonprofit charity.
• Privacy policy
• About Wikipedia
• Disclaimers

Ideal 4810

Location of Yamamoto in Miyagi Prefecture

Yamamoto (???; -ch?) is a town located in Watari District, Miyagi, Japan.

As of 2003, the town has an estimated population of 17,944 and a density of 278.29 persons per km². The total area is 64.48 km².

Transportation

Train stations

• JR East
  • J?ban Line: Sakamoto - Yamashita

Major roads

• Route 6

Wt Loss Medication

Chris Heister

Jump to: navigation, search

Chris Heister (born September 17, 1950 in Östhammar) is a Swedish Moderate Party politician and Leader of the Opposition on Stockholm County Council. She was elected to the Riksdag in 1991 and served until 2002. From 1999 to 2003, she was deputy chairman of the party. In 2002, she chose to step down from the Riksdag to pursue a career in Stockholm’s local politics. Having experience as a health spokesman in the Rikdag, she is very active on health issues - the main function of Stockholm County Council.

Heister is the with high probability the next Chief Commissioner in the new Moderate Party administration in the Stockholm County Council after the 2006 election.

This Swedish biographical article is a stub. You can help Wikipedia by expanding it.

Retrieved from “http://en.wikipedia.org/wiki/Chris_Heister”
Categories: 1950 births | Living people | Swedish Moderate Party politicians | Members of the parliament of Sweden | Municipal commissioners of Sweden | Women mayors | Swedish people stubsHidden categories: All articles with unsourced statements | Articles with unsourced statements since April 2008

Views

• Article
• Discussion
• Edit this page
• History

Personal tools

• Log in / create account

Navigation

• Main page
• Contents
• Featured content
• Current events
• Random article

Search

Interaction

• About Wikipedia
• Community portal
• Recent changes
• Contact Wikipedia
• Donate to Wikipedia
• Help

Toolbox

• What links here
• Related changes
• Upload file
• Special pages
• Printable version
• Permanent link
• Cite this page

Languages

• Svenska

• This page was last modified on 17 November 2008, at 15:38.
• All text is available under the terms of the GNU Free Documentation License. (See Copyrights for details.)
  Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a U.S. registered 501(c)(3) tax-deductible nonprofit charity.
• Privacy policy
• About Wikipedia
• Disclaimers

Lose Weight Fast Plans

“ring!Ring!!RING!!!”
Single by Aiko Kayo
Released	December 1, 2004
Format	CD single
Genre	J-Pop
Label	AVEX Records
Writer(s)	Kenn Kato
Aiko Kayo singles chronology
Ienai Kotoba (2004) ring!Ring!!RING!!! (2004) Traveller (2004)

ring!Ring!!RING!!! is Aiko Kayo’s fifth single. It was released on December 1, 2004, by AVEX Records.

ring!Ring!!RING!!! was used as the 2004 Christmas theme for Sanrio Co., Ltd. First pressings of the single included a pair of original rumika.

Track listing

1. ring!Ring!!RING!!!
2. ring!Ring!!RING!!! (Instrumental)

Need To Lose Weight For Wedding

It was founded on 16 October 1811 as the National Society for Promoting the Education of the Poor in the Principles of the Established Church in England and Wales. Its aim was that “the National Religion should be made the foundation of National Education, and should be the first and chief thing taught to the poor, according to the excellent Liturgy and Catechism provided by our Church.” One of the principal founders was Joshua Watson. Historically, schools founded by the National Society were called “national schools”, as opposed to the non-denominational “British schools” founded by the British and Foreign School Society.

According to the Society’s website, “Five thousand Church of England and Church in Wales schools, educating almost a million children and young people, are the heirs of that proud tradition.”

References

• Dr H. J. Burgess and Dr Paul Welsby, Short History of the National Society: 1811-1961 (1961)
• Early education for the poor

zoom bonus

Bánánach

Jump to: navigation, search

In early Irish folklore, the bánánach are supernatural female beings who haunt battlefields. See also Banshee.

This article relating to a Celtic myth or legend is a stub. You can help Wikipedia by expanding it.

Retrieved from “http://en.wikipedia.org/wiki/B%C3%A1n%C3%A1nach”
Categories: Celtic mythology stubs

Views

• Article
• Discussion
• Edit this page
• History

Personal tools

• Log in / create account

Navigation

• Main page
• Contents
• Featured content
• Current events
• Random article

Search

Interaction

• About Wikipedia
• Community portal
• Recent changes
• Contact Wikipedia
• Donate to Wikipedia
• Help

Toolbox

• What links here
• Related changes
• Upload file
• Special pages
• Printable version
• Permanent link
• Cite this page

• This page was last modified on 5 April 2007, at 17:10.
• All text is available under the terms of the GNU Free Documentation License. (See Copyrights for details.)
  Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a U.S. registered 501(c)(3) tax-deductible nonprofit charity.
• Privacy policy
• About Wikipedia
• Disclaimers

Overweight Exercise

Nanotoxicology is the study of the toxicity of nanomaterials. Because of the small size and large surface area of nanomaterials, these materials have unique properties compared with their larger counterparts. The nanomaterials, even when they are made of inert elements like gold, become very active at a nanometer range. Nanotoxicological studies are intended to determine whether and to what extent these may pose a threat to the environment and to human beings. For instance, Diesel nanoparticles have been found to damage the cardiovascular system in a mouse model.

Human health and safety

Calls for tighter regulation of nanotechnology have occurred alongside a growing debate related to the human health and safety risks associated with nanotechnology. The Royal Society identifies the potential for nanoparticles to penetrate the skin, and recommend that the use of nanoparticles in cosmetics be conditional upon a favorable assessment by the relevant European Commission safety advisory committee. Andrew Maynard also reports that ‘certain nanoparticles may move easily into sensitive lung tissues after inhalation, and cause damage that can lead to chronic breathing problems’.

Carbon nanotubes – characterized by their microscopic size and incredible tensile strength – are frequently likened to asbestos, due to their needle-like fiber shape. In a recent study that introduced carbon nanotubes into the abdominal cavity of mice, results demonstrated that long thin carbon nanotubes showed the same effects as long thin asbestos fibers, raising concerns that exposure to carbon nanotubes may lead to mesothelioma (cancer of the lining of the lungs caused by exposure to asbestos). Given these risks, effective and rigorous regulation has been called for to determine if, and under what circumstances, carbon nanotubes are manufactured, as well as ensuring their safe handling and disposal.

The Woodrow Wilson Centre’s Project on Emerging Technologies conclude that there is insufficient funding for human health and safety research, and as a result there is currently limited understanding of the human health and safety risks associated with nanotechnology. While the US National Nanotechnology Initiative reports that around four percent (about $40 million) is dedicated to risk related research and development, the Woodrow Wilson Centre estimate that only around $11 million is actually directed towards risk related research. They argued in 2007 that it would be necessary to increase funding to a minimum of $50 million in the following two years so as to fill the gaps in knowledge in these areas.

The potential for workplace exposure was highlighted by the 2004 Royal Society report which recommended a review of existing regulations to assess and control workplace exposure to nanoparticles and nanotubes. The report expressed particular concern for the inhalation of large quantities of nanoparticles by workers involved in the manufacturing process.

Stakeholders concerned by the lack of a regulatory framework to assess and control risks associated with the release of nanoparticles and nanotubes have drawn parallels with bovine spongiform encephalopathy (‘mad cow’s disease), thalidomide, genetically modified food),) nuclear energy, reproductive technologies, biotechnology, and asbestosis. In light of such concerns, the Canadian based ETC Group have called for a moratorium on nano-related research until comprehensive regulatory frameworks are developed that will ensure workplace safety.

Toxicology of nanoparticles

This section needs subsections. Please format the article according to the guidelines laid out at Wikipedia:Manual of Style (headings).

Nanotoxicology is a sub-specialty of particle toxicology. It addresses the toxicology of nanoparticles (particles <100 nm diameter) which appear to have some toxic effects that are unusual and not seen with larger particles. Nanoparticles can be divided into combustion-derived nanoparticles (like diesel soot), manufactured nanoparticles like carbon nanotubes and naturally occurring nanoparticles from volcanic eruptions, atmospheric chemistry etc. Typical nanoparticles that have been studied are titanium dioxide, alumina, zinc oxide, carbon black, and carbon nanotubes, and “nano-C₆₀“. Nanoparticles seem to have some different properties from larger particles that are known to have pathogenic effects, like asbestos or quartz. These differences seem to be a result of their size. They have a larger surface area per unit mass, so that in some cases they may have more pro-inflammatory effects (in, for example, lung tissue). In addition, some nanoparticles seem to be able to translocate from their site of deposition to distant sites such as the blood and the brain. This has resulted in a sea-change in how particle toxicology is viewed- instead of being confined to the lungs, nanoparticle toxicologists study the brain, blood, liver, skin and gut. Nanotoxicology has revolutionised particle toxicology and rejuvenated it.

The smaller a particle is, the greater its surface area to volume ratio and the higher its chemical reactivity and biological activity. The greater chemical reactivity of nanomaterials results in increased production of reactive oxygen species (ROS), including free radicals. ROS production has been found in a diverse range of nanomaterials including carbon fullerenes, carbon nanotubes and nanoparticle metal oxides. ROS and free radical production is one of the primary mechanisms of nanoparticle toxicity; it may result in oxidative stress, inflammation, and consequent damage to proteins, membranes and DNA.

The extremely small size of nanomaterials also means that they much more readily gain entry into the human body than larger sized particles do. How these nanoparticles behave inside the body is a major question that needs to be resolved. The behavior of nanoparticles is a function of their size, shape and surface reactivity with the surrounding tissue. In principle, a large number of particles could overload the body’s phagocytes, cells that ingest and destroy foreign matter, thereby triggering stress reactions that lead to inflammation and weaken the body’s defense against other pathogens. In addition to questions about what happens if non-degradable or slowly degradable nanoparticles accumulate in bodily organs, another concern is their potential interaction with biological processes inside the body. Because of their large surface area, nanoparticles will, on exposure to tissue and fluids, immediately adsorb onto their surface some of the macromolecules they encounter. This may, for instance, affect the regulatory mechanisms of enzymes and other proteins.

Nanomaterials are able to cross biological membranes and access cells, tissues and organs that larger-sized particles normally cannot. Nanomaterials can gain access to the blood stream following inhalation or ingestion. At least some nanomaterials can penetrate the skin; even larger microparticles may penetrate skin when it is flexed. Broken skin is an ineffective particle barrier, suggesting that acne, eczema, shaving wounds or severe sunburn may accelerate skin uptake of nanomaterials. Then, once in the blood stream, nanomaterials can be transported around the body and be taken up by organs and tissues, including the brain, heart, liver, kidneys, spleen, bone marrow and nervous system. Nanomaterials have proved toxic to human tissue and cell cultures, resulting in increased oxidative stress, inflammatory cytokine production and cell death. Unlike larger particles, nanomaterials may be taken up by cell mitochondria and the cell nucleus. Studies demonstrate the potential for nanomaterials to cause DNA mutation and induce major structural damage to mitochondria, even resulting in cell death. Size is therefore a key factor in determining the potential toxicity of a particle. However it is not the only important factor.

Other properties of nanomaterials that influence toxicity include: chemical composition, shape, surface structure, surface charge, aggregation and solubility, and the presence or absence of functional groups of other chemicals. The large number of variables influencing toxicity means that it is difficult to generalise about health risks associated with exposure to nanomaterials – each new nanomaterial must be assessed individually and all material properties must be taken into account.

Since there is no authority to govern nanotech-based products, there are many products that could possibly be dangerous to humans. Scientific research has indicated the potential for some nanomaterials to be toxic to humans or the environment. In March 2004 tests conducted by environmental toxicologist Eva Oberdörster, Ph.D. working with Southern Methodist University in Texas, found extensive brain damage to fish exposed to fullerenes for a period of just 48 hours at a relatively moderate dose of 0.5 parts per million (commensurate with levels of other kinds of pollution found in bays). The fish also exhibited changed gene markers in their livers, indicating their entire physiology was affected. In a concurrent test, the fullerenes killed water fleas, an important link in the marine food chain. The extremely small size of fabricated nanomaterials also means that they are much more readily taken up by living tissue than presently known toxins. Nanoparticles can be inhaled, swallowed, absorbed through skin and deliberately or accidentally injected during medical procedures. They might be accidentally or inadvertently released from materials implanted into living tissue.

Researcher Shosaku Kashiwada of the National Institute for Environmental Studies in Tsukuba, Japan, in a more recent study, intended to further investigate the effects of nanoparticles on soft-bodied organisms. His study allowed him to explore the distribution of water-suspended fluorescent nanoparticles throughout the eggs and adult bodies of a species of fish, known as the see-through medaka (Oryzias latipes). See-through medaka were used because of their small size, wide temperature and salinity tolerances, and short generation time. Moreover, small fish like the see-through medaka have been popular test subjects for human diseases and organogenesis for other reasons as well, including their transparent embryos, rapid embryo development, and the functional equivalence of their organs and tissue material to that of mammals. Because the see-through medaka have transparent bodies, analyzing the deposition of fluorescent nanoparticles throughout the body is quite simple. For his study, Dr. Kashiwada evaluated four aspects of nanoparticle accumulation. These included the overall accumulation and the size-dependent accumulation of nanoparticles by medaka eggs, the effects of salinity on the aggregation of nanoparticles in solution and on their accumulation by medaka eggs, and the distribution of nanoparticles in the blood and organs of adult medaka. It was also noted that nanoparticles were in fact taken up into the bloodstream and deposited throughout the body. In the medaka eggs, there was a high accumulation of nanoparticles in the yolk; most often bioavailibility was dependent on specific sizes of the particles. Adult samples of medaka had accumulated nanoparticles in the gills, intestine, brain, testis, liver, and bloodstream. One major result from this study was the fact that salinity may have a large influence on the bioavailibility and toxicity of nanoparticles to penetrate membranes and eventually kill the specimen.

As the use of nanomaterials increases worldwide, concerns for worker and user safety are mounting. To address such concerns, the Swedish Karolinska Institute conducted a study in which various nanoparticles were introduced to human lung epithelial cells. The results, released in 2008, showed that iron oxide nanoparticles caused little DNA damage and were non-toxic. Zinc oxide nanoparticles were slightly worse. Titanium dioxide caused only DNA damage. Carbon nanotubes caused DNA damage at low levels. Copper oxide was found to be the worst offender, and was the only nanomaterial identified by the researchers as a clear health risk.

No Fullerene toxicity reported

Nanoparticles can also be made of C60, as is the case with almost any room temperature solid, and several groups have done this and studied toxicity of such particles. The results in the work of Oberdörster at Southern Methodist University, published in “Environmental Health Perspectives” in July 2004, in which questions were raised of potential cytotoxicity, has now been shown by several sources to be likely caused by the tetrahydrofuran used in preparing the 30 nm - 100 nm particles of C60 used in the research. Isakovic, et al., Biomaterials, 27, 5049-5058, 2006, who review this phenomenon, gives results showing that removal of THF from the C60 particles resulted in a loss of toxicity. Sayes, et al. Nanoletters, 2007. 7, (8), pp. 2399 - 2406, also show that particles prepared as in Oberdorster caused no detectable inflammatory response when instilled intratracheally in rats after observation for 3 months, suggesting that even the particles prepared by Oberdorster do not exhibit markers of toxicity in mammalian models. This work used as a benchmark quartz particles, which did give an inflammatory response.

A comprehensive and recent review of work on fullerene toxicity is available in “Toxicity Studies of Fullerenes and Derivatives,” a chapter from the book “Bio-applications of Nanoparticles” (Chan ed., Landes Bioscience, 2007). In this work, the authors review the work on fullerene toxicity beginning in the early 1990’s to present, and conclude that the evidence gathered since the discovery of fullerenes overwhelmingly points to C60 being non-toxic. As is the case for toxicity profile with any chemical modification of a structural moiety, the authors suggest that individual molecules be assessed individually.

References

1. ^ http://www.bloomberg.com/apps/news?pid=washingtonstory&sid=aBt.yLf.YfOo study Pollution Particles Lead to Higher Heart Attack Risk (Update1)
2. ^ Andrew Maynard. “Nanotechnology: A Research Strategy for Addressing Risks“.
3. ^ Poland C, et al (2008). “Carbon Nanotubes Introduced into the Abdominal Cavity of Mice Show Asbestos-Like Pathogenicity in a Pilot-Study”. Nature Nanotechnology. doi:10.1038/nnano.2008.111, http://www.nature.com/nnano/journal/vaop/ncurrent/abs/nnano.2008.111.html. 
4. ^ Woodrow Wilson Centre for International Scholars Project on Emerging Nanotechnologies
5. ^ . “An Issues Landscape for Nanotechnology Standards. Report of a Workshop“. Institute for Food and Agricultural Standards, Michigan State University, East Lansing.
6. ^ Royal Society and Royal Academy of Engineering (2004). “Nanoscience and nanotechnologies: opportunities and uncertainties“. Retrieved on 2008-05-18.
7. ^ Rowe G, Horlick-Jones T, Walls J, Pidgeon N, (2005). “Difficulties in evaluating public engagement initiatives: reflections on an evaluation of the UK GM Nation?”. Public Understanding of Science 14: 331–352. doi:10.1177/0963662505056611, http://pus.sagepub.com/cgi/content/abstract/14/4/331. 
8. ^ ^{a b c} Nel, Andre; et al. (3 February 2006). “Toxic Potential of Materials at the Nanolevel”. Science 311 (5761): 622–627. doi:10.1126/science.1114397. PMID 16456071.  doi:10.1126/science.1114397
9. ^ Holsapple, Michael P.; et al. (2005). “Research Strategies for Safety Evaluation of Nanomaterials, Part II: Toxicological and Safety Evaluation of Nanomaterials, Current Challenges and Data Needs”. Toxicological Sciences 88 (1): 12–17. doi:10.1093/toxsci/kfi293. PMID 16120754.  doi:10.1093/toxsci/kfi293
10. ^ ^{a b c} Oberdörster, Günter; et al. (2005). “Principles for characterizing the potential human health effects from exposure to nanomaterials: elements of a screening strategy”. Particle and Fibre Toxicology 2: 8. doi:10.1186/1743-8977-2-8.  doi:10.1186/1743-8977-2-8
11. ^ ^{a b} Hoet, Peter HM; et al. (2004). “Nanoparticles – known and unknown health risks”. Journal of Nanobiotechnology 2: 12. doi:10.1186/1477-3155-2-12.  doi:10.1186/1477-3155-2-12
12. ^ Ryman-Rasmussen, Jessica P.; et al. (2006). “Penetration of Intact Skin by Quantum Dots with Diverse Physicochemical Properties”. Toxicological Sciences 91 (1): 159–165. doi:10.1093/toxsci/kfj122. PMID 16443688.  doi:10.1093/toxsci/kfj122
13. ^ Tinkle, Sally S.; et al. (July 2003). “Skin as a Route of Exposure and Sensitization in Chronic Beryllium Disease”. Environmental Health Perspectives 111 (9): 1202–1208. 
14. ^ ^{a b c} “Nanotoxicology: An Emerging Discipline Evolving from Studies of Ultrafine Particles”. Environmental Health Perspectives 113 (7): 823–839. July 2005.  doi:10.1289/ehp.7339
15. ^ ^{a b} Li, Ning; et al. (April 2003). “Ultrafine particulate pollutants induce oxidative stress and mitochondrial damage”. Environmental Health Perspectives 111 (4): 455–460. 
16. ^ Porter, Alexandra E.; et al. (2007). “Visualizing the Uptake of C60 to the Cytoplasm and Nucleus of Human Monocyte-Derived Macrophage Cells Using Energy-Filtered Transmission Electron Microscopy and Electron Tomography”. Environmental Science and Technology 41 (8): 3012–3017. doi:10.1021/es062541f.  doi:10.1021/es062541f
17. ^ ^{a b} Geiser, Marianne; et al. (November 2005). “Ultrafine Particles Cross Cellular Membranes by Nonphagocytic Mechanisms in Lungs and in Cultured Cells”. Environmental Health Perspectives 113 (11): 1555–1560.  doi:10.1289/ehp.8006
18. ^ Savic, Radoslav; et al. (25 April 2003). “Micellar Nanocontainers Distribute to Defined Cytoplasmic Organelles”. Science 300 (5619): 615–618. doi:10.1126/science.1078192. PMID 12714738.  doi:10.1126/science.1078192
19. ^ Magrez, Arnaud; et al. (2006). “Cellular Toxicity of Carbon-Based Nanomaterials”. Nano Letters 6 (6): 1121–1125. doi:10.1021/nl060162e.  doi:10.1021/nl060162e
20. ^ Kashiwada, Shosaku. “Distribution of Nanoparticles in the See-through Medaka (Oryzias latipes).” Environmental Health Perspectives. November 2006: Volume 114.
21. ^ Chemical & Engineering News Vol. 86 No. 35, 1 Sept. 2008, “Study Sizes up Nanomaterial Toxicity”, p. 44

Further reading

• Donaldson, K., Stone, V., Tran, C. L., Kreyling, W., and Borm, P. J. (2004). Nanotoxicology. Occup. Environ Med. 61(9), 727-728.

• Singh, S. and Nalwa H. S. (2007) Nanotechnology and Health Safety - Toxicity and Risk Assessments of Nanostructured Materials on Human Health. Journal of Nanoscience and Nanotechnology 7, 3048-3070.

betsey johnson rockin cherries

When X-rays hit an atom, they make the electronic cloud move as does any electromagnetic wave. The movement of these charges re-radiates waves with the same frequency (blurred slightly due to a variety of effects); this phenomenon is known as the Rayleigh scattering (or elastic scattering). The scattered waves can themselves be scattered but this secondary scattering is assumed to be negligible. A similar process occurs upon scattering neutron waves from the nuclei or by a coherent spin interaction with an unpaired electron. These re-emitted wave fields interfere with each other either constructively or destructively (overlapping waves either add together to produce stronger peaks or subtract from each other to some degree), producing a diffraction pattern on a detector or film. The resulting wave interference pattern is the basis of diffraction analysis. Both neutron and X-ray wavelengths are comparable with inter-atomic distances (~150 pm) and thus are an excellent probe for this length scale.

The interference is constructive when the phase shift is a multiple to 2?; this condition can be expressed by Bragg’s law:

where

• n is an integer determined by the order given,
• ? is the wavelength of x-rays, and moving electrons, protons and neutrons,
• d is the spacing between the planes in the atomic lattice, and
• ? is the angle between the incident ray and the scattering planes

According to the 2? deviation, the phase shift causes constructive (left figure) or destructive (right figure) interferences

Note that moving particles, including electrons, protons and neutrons, have an associated De Broglie wavelength.

Reciprocal space

Although the misleading common opinion reigns that Bragg’s Law measures atomic distances in real space, it does not. Furthermore, the term demonstrates that it measures the number of wavelengths fitting between two rows of atoms, thus measuring reciprocal distances. Max von Laue had interpreted this correctly in a vector form, the Laue equation

where is a reciprocal lattice vector and and are the wave vectors of the incident and the diffracted beams.

Together with the condition for elastic scattering | k_f | = | k_i | and the introduction of the scattering angle 2? this leads equivalently to Bragg’s equation.

The concept of reciprocal lattice is the Fourier space of a crystal lattice and necessary for a full mathematical description of wave mechanics.

Alternate Derivation

A single monochromatic wave, of any type, is incident on aligned planes of lattice points, with separation d, at angle ?, as shown below.

There will be a path difference between the ‘ray’ that gets reflected along AC’ and the ray that gets transmitted, then reflected along AB and BC paths respectively. This path difference is:

If this path difference is equal to any integer value of the wavelength then the two separate waves will arrive at a point with the same phase, and hence undergo constructive interference. Expressed mathematically:

Using the Pythagorean theorem it is easily shown that:

and and

also it can be shown that:

Putting everything together and using known identities for sinusoidal functions:

Which simplifies to:

yielding Bragg’s law.

References

W.L. Bragg, “The Diffraction of Short Electromagnetic Waves by a Crystal”, Proceedings of the Cambridge Philosophical Society, 17 (1913), 43–57.

1. ^ There are some sources, like the Academic American Encyclopedia, that attribute the discovery of the law to both W.L Bragg and his father W.H. Bragg, but the official Nobel Prize site and the biographies written about him (Light Is a Messenger: The Life and Science of William Lawrence Bragg, Graeme K. Hunter, 2004 and “Great Solid State Physicists of the 20th Century”, Julio Antonio Gonzalo, Carmen Aragó López) make a clear statement that William Lawrence Bragg alone derived the law.
2. ^ See for example this example calculation of interatomic spacing with Bragg’s law.

ann demeulemeester boots

His father, the 1st Baronet, was Speaker of the House of Commons.

He married Jane Thelwall, the great-granddaughter of Sir John Wynn, 1st Baronet. Her relative Sir John bequeathed the entire Wynnstay estate to her; since he and Sir William Williams were the two largest landowners in north Wales at that time, together the combined estate dwarfed all others. In honour of his wife’s ancestry, Sir William changed his name to Sir William Williams-Wynn of Wynnstay.

Weight Losing Plans