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id stringlengths 40 40	title stringlengths 15 120	text stringlengths 41 3.14k	source stringclasses 2 values
6cf665484d1ce3b477341c32e6dc10cfe0b596af	the specimen goniometer of a tem is thereby	the specimen goniometer of a tem is thereby employed analogously to the goniometer head of an optical goniometer. the optical axis of the tem is then analogous to the reference direction of an optical goniometer. while in optical goniometry net-plane normals (reciprocal lattice vectors) need to be successively aligned ...	wikipedia
59cabd3e9f18319f598f68c04010d3caa29142cf	since steno's law can be further generalized for	since steno's law can be further generalized for a single crystal of any material to include the angles between either all identically indexed net planes (i.e. vectors of the reciprocal lattice, also known as 'potential reflections in diffraction experiments') or all identically indexed lattice directions (i.e. vectors...	wikipedia
a91d68b75aa7ed607805a3ad52807f743045e063	it is in many cases possible to derive	it is in many cases possible to derive the ratios of the crystal axes for crystals with low symmetry from optical goniometry with high accuracy and precision and to identify a crystalline material on their basis alone employing databases such as 'crystal data'. provided that the crystal faces have been correctly indexe...	wikipedia
504b17bbdc6b96debe129cc491256f29965afee6	the generalized steno law states that the interfacial	the generalized steno law states that the interfacial angles between identical faces of any single crystal of the same material are, by nature, restricted to the same value. this offers the opportunity to fingerprint crystalline materials on the basis of optical goniometry, which is also known as crystallometry. in ord...	wikipedia
8d5b27c4a2bc27bee2d27915f62acec2b2a859c5	fourier transforms of hrtem images, on the other	fourier transforms of hrtem images, on the other hand, supply information not only about the projected reciprocal lattice geometry and structure factor amplitudes, but also structure factor phase angles. after crystallographic image processing, structure factor phase angles are far more reliable than structure factor a...	wikipedia
f3d11f964f5685beef2ff170d5dac6d9a4b9c703	in the case of electron diffraction patterns, structure	in the case of electron diffraction patterns, structure factor amplitudes can be used, in a later step, to further discern among a selection of candidate structures (so-called 'structure factor fingerprinting'). structure factor amplitudes from electron diffraction data are far less reliable than their counterparts fro...	wikipedia
2ef8c6abb787b25c022f4962eed802cbda289c3c	projected lattice geometries can be represented by so-called	projected lattice geometries can be represented by so-called ‘ lattice-fringe fingerprint plots ’ (lffps), also called angular covariance plots. the horizontal axis of such a plot is given in reciprocal lattice length and is limited by the point resolution of the microscope. the vertical axis is defined as acute angle ...	wikipedia
5bac833cec40fd6205dae863f10e73ee01a5e4af	high-resolution transmission electron microscopy (hrtem) provides images and	high-resolution transmission electron microscopy (hrtem) provides images and diffraction patterns of nanometer sized crystallites. fourier transforms of hrtem images and electron diffraction patterns both supply information about the projected reciprocal lattice geometryfor a certain crystal orientation, where the proj...	wikipedia
573b37e7d6b3a01a7e90babca356cd452a33dd85	powder diffraction patterns of very small single crystals,	powder diffraction patterns of very small single crystals, or crystallites, are subject to size-dependent peak broadening, which, below a certain size, renders powder diffraction fingerprinting useless. in this case, peak resolution is only possible in 3d reciprocal space,i.e. by applying single-crystal electron diffra...	wikipedia
5ca294d24b6c18e59707bf150405affa756860ce	x-ray powder diffraction fingerprinting has become the standard	x-ray powder diffraction fingerprinting has become the standard tool for the identification of single or multiple crystal phases and is widely used in such fields as metallurgy, mineralogy, forensic science, archeology, condensed matter physics, and the biological and pharmaceutical sciences.	wikipedia
2f7e9f25cb30098d0d67abe4db3e2de634f65625	search-match algorithms compare selected test reflections of an	search-match algorithms compare selected test reflections of an unknown crystal phase with entries in the database. intensity-driven algorithms utilize the three most intense lines (so-called ‘hanawalt search’), while d -spacing-driven algorithms are based on the eight to ten largest d -spacings (so-called ‘fink search...	wikipedia
78b654b282263d8f91e00d00f9e4b6e0aded5be5	powder diffraction data can be plotted as diffracted	powder diffraction data can be plotted as diffracted intensity (i) versus reciprocal lattice spacing (1/ d). reflection positions and intensities of known crystal phases, mostly from x-ray diffraction data, are stored, as d - i data pairs, in the powder diffraction file (pdf) database. the list of d - i data pairs is h...	wikipedia
c2680aebea11de7dbe63458a9ce693a3cc451a8c	applying standard diffraction techniques to crystal powders or	applying standard diffraction techniques to crystal powders or polycrystals is tantamount to collapsing the 3d reciprocal space, as obtained via single-crystal diffraction, onto a 1d axis. the resulting partial-to-total overlap of symmetry-independent reflections renders the structure determination process more difficu...	wikipedia
fe01cedcc625fdf1a394ae9b9563c0218ea9b462	crystal phases can be identified by successfully matching	crystal phases can be identified by successfully matching suitable crystallographic parameters with their counterparts in database entries. prior knowledge of the chemical composition of the crystal phase can be used to reduce the number of database entries to a small selection of candidate structures and thus simplify...	wikipedia
518ceab75063df1630827b99992bd63571f38c1e	crystal phases are defined as regions with the	crystal phases are defined as regions with the same crystal structure, irrespective of orientation or twinning. single and twinned crystalline specimens therefore constitute individual crystal phases. polycrystalline or crystal powder samples may consist of more than one crystal phase. such a phase comprises all the cr...	wikipedia
41e58bba09af675c9579837b7cf47d78c287ea29	polycrystals are made of a large number of	polycrystals are made of a large number of small single crystals, or crystallites, held together by thin layers of amorphous solid. crystal powder is obtained by grinding crystals, resulting in powder particles, made up of one or more crystallites. both polycrystals and crystal powder consist of many crystallites with ...	wikipedia
7b35f38afa26d5a1f82c109eb968ef039f62c630	crystalline material may be divided into single crystals,	crystalline material may be divided into single crystals, twin crystals, polycrystals, and crystal powder. in a single crystal, the arrangement of atoms, ions, or molecules is defined by a single crystal structure in one orientation. twin crystals, on the other hand, consist of single-crystalline twin domains, which ar...	wikipedia
3c0ff3e5ad54aa593ed06f7ebc347882ae773229	modern versions of crystallographic databases are based on	modern versions of crystallographic databases are based on the relational database model. communication with the database usually happens via a dialect of the structured query language (sql). web-based databases typically process the search algorithm on the server interpreting supported scripting elements, while deskto...	wikipedia
91091d6d9a400995f2b2d6d1fc860207708f56ae	more sophisticated algorithms depend on the material type	more sophisticated algorithms depend on the material type covered. organic compounds might be searched for on the basis of certain molecular fragments. inorganic compounds, on the other hand, might be of interest with regard to a certain type of coordination geometry. more advanced algorithms deal with conformation ana...	wikipedia
0cfec5c57132ee43f55a149d8b0317264536782d	search capacities of crystallographic databases differ widely. basic	search capacities of crystallographic databases differ widely. basic functionality comprises search by keywords, physical properties, and chemical elements. of particular importance is search by compound name and lattice parameters. very useful are search options that allow the use of wildcard characters and logical co...	wikipedia
4f5dbcf9675f6dd373c6636b23a69f2d7329dbef	crystallographic databases can specialize in crystal structures, crystal	crystallographic databases can specialize in crystal structures, crystal phase identification, crystallization, crystal morphology, or various physical properties. more integrative databases combine several categories of compounds or specializations. structures of incommensurate phases, 2d materials, nanocrystals, thin...	wikipedia
b4887894b95c8a5c4ee501f441da838f040d83ec	in terms of user numbers and daily access	in terms of user numbers and daily access rates, comprehensive and thoroughly vetted open-access crystal structure databases naturally surpass comparable databases with more restricted access and usage rights. independent of comprehensiveness, open-access crystal structure databases have spawned open-source software pr...	wikipedia
837073ed9492b98606f24bae8894c5f8736a207f	comprehensiveness can refer to the number of entries	comprehensiveness can refer to the number of entries in a database. on those terms, a crystal structure database can be regarded as comprehensive, if it contains a collection of all (re-)published crystal structures in the category of interest and is updated frequently. searching for structures in such a database can r...	wikipedia
4089d26588a1ec2c624616145544ab27262b5d1f	crystal structures are typically categorized as minerals, metals	crystal structures are typically categorized as minerals, metals - alloys, inorganics, organics, nucleic acids, and biological macromolecules. individual crystal structure databases cater for users in specific chemical, molecular-biological, or related disciplines by covering super- or subsets of these categories. mine...	wikipedia
ad595fed466abb84b5879b54d4a4827068e237d7	as of 2008, more than 700,000 crystal structures	as of 2008, more than 700,000 crystal structures had been published and stored in crystal structure databases. the publishing rate has reached more than 50,000 crystal structures per year. these numbers refer to published and republished crystal structures from experimental data. crystal structures are republished owin...	wikipedia
1307191a77d6c821257e90579c122d12ec263a77	crystal structure data in cif format are linked	crystal structure data in cif format are linked to scientific articles as supplementary material. cifs may be accessible directly from the publisher's website, crystallographic databases, or both. in recent years, many publishers of crystallographic journals have come to interpret cifs as formatted versions of open dat...	wikipedia
8ec36089af3e22053f5e9af7a0794779a8038608	the increasing automation of the crystal structure determination	the increasing automation of the crystal structure determination process has resulted in ever higher publishing rates of new crystal structures and, consequentially, new publishing models. minimalistic articles contain only crystal structure tables, structure images, and, possibly, abstract-like structure description. ...	wikipedia
19e3fa055035f3dc2e0ba433bec0ad74381a0706	data exchange among crystallographic databases, structure visualization software,	data exchange among crystallographic databases, structure visualization software, and structure refinement programs has been facilitated by the emergence of the crystallographic information file (cif) format. the cif format is the standard file format for the exchange and archiving of crystallographic data. it was adop...	wikipedia
fadcb6496d962cd3ab585e87cc5182b4867127cb	crystallographic data are primarily extracted from published scientific	crystallographic data are primarily extracted from published scientific articles and supplementary material. newer versions of crystallographic databases are built on the relational database model, which enables efficient cross-referencing of tables. cross-referencing serves to derive additional data or enhance the sea...	wikipedia
1cdc13d30e521ad36fcc7fceb7ef13004cdd855b	crystallographic databases differ in access and usage rights	crystallographic databases differ in access and usage rights and offer varying degrees of search and analysis capacity. many provide structure visualization capabilities. they can be browser based or installed locally. newer versions are built on the relational database model and support the crystallographic informatio...	wikipedia
416d9df4e5ede931680fa68df164d6e34b4e287d	crystal structures of nanometer sized crystalline samples can	crystal structures of nanometer sized crystalline samples can be determined via structure factor amplitude information from single-crystal electron diffraction data or structure factor amplitude and phase angle information from fourier transforms of hrtem images of crystallites. they are stored in crystal structure dat...	wikipedia
89c8eadcec7bd4c44f07809ab2a2f174a73dc702	crystal structures of crystalline material are typically determined	crystal structures of crystalline material are typically determined from x-ray or neutron single-crystal diffraction data and stored in crystal structure databases. they are routinely identified by comparing reflection intensities and lattice spacings from x-ray powder diffraction data with entries in powder-diffractio...	wikipedia
5ac4cab578e3c54c4267f95da308ecb14cad047d	a crystallographic database is a database specifically designed	a crystallographic database is a database specifically designed to store information about the structure of molecules and crystals. crystals are solids having, in all three dimensions of space, a regularly repeating arrangement of atoms, ions, or molecules. they are characterized by symmetry, morphology, and directiona...	wikipedia
c66f1905ce156fc28ea73a8411f01e0b08283a41	skywalker ranch is a movie ranch and the	skywalker ranch is a movie ranch and the workplace of film director, writer and producer george lucas located in a secluded area near nicasio, california, in marin county. the ranch is located on lucas valley road, named after an early-20th-century landowner in the area of no relation to george lucas. the ranch is not ...	wikipedia
e52212c0c0fa1314b1f92394dc7e6deaf3ce5477	starting in 1988, lucasfilm sought approval to develop	starting in 1988, lucasfilm sought approval to develop another nearby property called grady ranch at 2400 lucas valley road. the most recent proposals called for a 263,701-square-foot (24,498.6 m) digital film production center for the property. however, in the wake of delays caused by local resistance and environmenta...	wikipedia
ca0feaf0cc6d33a6020738fcfb9742cfdb572520	the ranch comprises 1,061 acres (429 ha), of	the ranch comprises 1,061 acres (429 ha), of which 43 acres (17 ha) are developed with 317,000 sq ft (29,500 m) of office space. before the move to the presidio in 2005, big rock ranch housed the marketing, licensing, distribution and online divisions of lucasfilm. as of 2007 it was the headquarters of the animation di...	wikipedia
2416fb66b8dde3072f6e92fd7deb384740d353ac	big rock ranch is a later lucasfilm development	big rock ranch is a later lucasfilm development in marin county at 3800 lucas valley road adjacent to skywalker ranch. the county's planning commission approved this facility in september 1996 and construction was completed in august 2002. however, in november 2004, lucas announced that the 250 employees of the ranch w...	wikipedia
7d27f52c55b1c6d52a439a43345f9f0b6710f800	skywalker ranch is intended to be more of	skywalker ranch is intended to be more of a "filmmaker's retreat" than a headquarters for lucas's business operations. the headquarters of lucasfilm, industrial light & magic, and lucasarts (now lucasfilm games) are located in lucas's letterman digital arts center in the presidio of san francisco. the george lucas educ...	wikipedia
67626b53ae6eef6e58cd21a5c025cfc57bae8690	the ranch contains a barn with animals, vineyards,	the ranch contains a barn with animals, vineyards, a garden with fruits and vegetables used in the on-site restaurant, an outdoor swimming pool and fitness center with racquetball courts, the man-made " ewok lake", a hilltop observatory, a 300-seat theater called "the stag" as well as theater screening rooms, and parki...	wikipedia
b18713ab2a056424781eb9c54f8dd43882a6920a	in september 1978, george lucas purchased the first	in september 1978, george lucas purchased the first parcel of land, and named it bulltail ranch, which in subsequent years became skywalker ranch. lucasfilm acquired 3,000 acres (1,200 ha) of adjoining land for a total of over 4,700 acres (1,900 ha). only 15 acres (6.1 ha) have been developed. residents of the area hav...	wikipedia