text stringlengths 0 73.6k | source stringclasses 4
values |
|---|---|
Short Message Peer-to-Peer-Operation-Versions The SMPP standard has evolved during the time. The most commonly used versions of SMPP are: SMPP 3.3 the oldest used version (despite its limitations, it is still widely used); supports GSM only. Generates an immediate response for each message sent.
SMPP 3.4 adds optional ... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-PDU format (after version 3.4)-The SMPP PDUs are binary encoded for efficiency. They start with a header which may be followed by a body: PDU header Each PDU starts with a header. The header consists of 4 fields, each of length of 4 octets: command_length Is the overall length of the PDU in o... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-PDU format (after version 3.4)-command_status Always has a value of 0 in requests; in responses it carries information about the result of the operation sequence_number Is used to correlate requests and responses within an SMPP session; allows asynchronous communication (using a sliding windo... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Example-This is an example of the binary encoding of a 60-octet submit_sm PDU. The data is shown in Hex octet values as a single dump and followed by a header and body break-down of that PDU.
This is best compared with the definition of the submit_sm PDU from the SMPP specification in order t... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Example-PDU header 'command_length', (60) ... 00 00 00 3C 'command_id', (4) ... 00 00 00 04 'command_status', (0) ... 00 00 00 00 'sequence_number', (5) ... 00 00 00 05 PDU body 'service_type', () ... 00 'source_addr_ton', (2) ... 02 'source_addr_npi', (8) ... 08 'source_addr', (555) ... 35 3... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Quirks-Despite its wide acceptance, the SMPP has a number of problematic features: No data_coding for GSM 7-bit default alphabet Not standardized meaning of data_coding=0 Unclear support for Shift-JIS encoding Incompatibility of submit_sm_resp between SMPP versions Using of SMPP 3.3 SMSC Deli... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Quirks-Not standardized meaning of data_coding=0 According to SMPP 3.4 and 5.0 the data_coding=0 means ″SMSC Default Alphabet″. Which encoding it really is, depends on the type of the SMSC and its configuration. | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Quirks-Unclear support for Shift-JIS encoding One of the encodings in CDMA standard C.R1001 is Shift-JIS used for Japanese. SMPP 3.4 and 5.0 specifies three encodings for Japanese (JIS, ISO-2022-JP and Extended Kanji JIS), but none of them is identical with CDMA MSG_ENCODING 00101. It seems t... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Quirks-Incompatibility of submit_sm_resp between SMPP versions When a submit_sm fails, the SMSC returns a submit_sm_resp with non-zero value of command_status and ″empty″ message_id.
SMPP 3.3 explicitly states about the message_id field ″If absent this field must contain a single NULL byte″. ... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Quirks-SMPP 5.0 just specifies that message_id is a mandatory parameter of the type C-Octet string of the submit_sm_resp message. According to the section 3.1.1 NULL Settings, ″A NULL string ″″ is encoded as 0x00″. The length of the PDU is at least 17 octets.For the best compatibility, any SM... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Quirks-The original intention of error scenarios was that no body would be returned in the PDU response. This was the standard behavior exhibited on all Aldiscon/Logica SMSC and also in most of the other vendors. When SMPP 3.4 was being taken on by the WAP forum, several clarifications were r... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Extensibility, compatibility and interoperability-Since introduction of TLV parameters in version 3.4, the SMPP may be regarded an extensible protocol. In order to achieve the highest possible degree of compatibility and interoperability any implementation should apply the Internet robustness... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Extensibility, compatibility and interoperability-Ignore any unrecognised, unexpected or unsupported TLV parameters. | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Extensibility, compatibility and interoperability-The borders of PDUs are always given by the PDUs' command_length field. Any message field must not exceed the end of PDU. If a field is not properly finished, it should be treated as truncated at the end of PDU, and it should not affect furthe... | milkshake721/2.1M-wiki-STEM |
Short Message Peer-to-Peer-Security-The SMPP protocol is designed on a clear-text binary protocol which needs to be considered if using for potentially sensitive information such as one-time passwords via SMS. There are, however, implementations of SMPP over secure SSL/TLS if required. | milkshake721/2.1M-wiki-STEM |
EA-2012-EA-2012-EA-2012 is an extremely toxic organophosphate nerve agent. It's an extremely potent acetylcholinesterase inhibitor that is resistant to atropine and oxime treatment. | milkshake721/2.1M-wiki-STEM |
Pixia-Pixia-Pixia is a freeware raster graphics editor program for Windows, created by Isao Maruoka. It was originally designed for the anime/manga community but has also been used in other branches of art. Besides the primary Japanese interface, it is also available in English, French, Italian, Spanish, Hungarian, Ch... | milkshake721/2.1M-wiki-STEM |
Pixia-Reception-A CNET Editors' Review in January 2011 called Pixia "one of the most capable and professional Photoshop alternatives we've tried." | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-AppleColor High-Resolution RGB Monitor-Apple Inc. sold a variety of LCD and CRT computer displays in the past. Apple paused production of their own standalone displays in 2016 and partnered with LG to design displays for Macs. In June 2019, the Pro Display XDR was introduced, howe... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-CRT displays-In the beginning (throughout the 1970s), Apple did not manufacture or sell displays of any kind, instead recommending users plug-into their television sets or (then) expensive third party monochrome monitors. However, in order to offer complete systems through its dea... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-CRT displays-First generation Apple's manufacture history of CRT displays began in 1980, starting with the Monitor /// that was introduced alongside and matched the Apple III business computer. It was a 12″ monochrome (green) screen that could display 80×24 text characters and any... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-CRT displays-Three years later came the introduction of the Apple manufactured Monitor //, which as the name implies, was more suited in look and style for the Apple II line and at the same time added improvements in features and visual quality. In 1984 a miniature 9″ screen, call... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-CRT displays-In 1986 came the introduction of the AppleColor RGB Monitor, a 12″ analog RGB display designed specifically for the Apple IIGS computer. It supported a resolution of 640×400 interlaced (640×200 non-interlaced) and could be used by the Macintosh II, in a limited fashio... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-CRT displays-Second generation The second generation of displays were built into the Lisa and Macintosh computers. The Macintosh had a 9-inch monochrome display that could display 512×342 pixels which would be used in all monochrome Compact Macintosh computers. | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-CRT displays-A new external AppleColor High-Resolution RGB Monitor was introduced in 1987 for the Macintosh II. It had a 13″ Trinitron CRT (the first Apple display to use an aperture grille CRT) with a fixed resolution of 640×480 pixels. The Macintosh II was a modular system with ... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-CRT displays-Third generation The third generation of displays marked the end of the monochrome display era and the beginning of the multimedia era. The first display to include built-in speakers was introduced in 1993 as the Apple AudioVision 14 Display. The "Multiple Scan" serie... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-CRT displays-The Macintosh Color Classic introduced a 10″ color Trinitron display to the Classic compact Macintosh, with a slightly enhanced resolution of 512×384 (560×384 to accommodate the Apple IIe Card) like the standalone 12″ color display. Apple continued the all-in-one seri... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-CRT displays-Fourth generation The fourth generation of displays were introduced simultaneously with the Blue & White Power Macintosh G3 in 1999, which included the translucent plastics of the iMac (initially white and blue "blueberry", then white and grey "graphite" upon the intr... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-The history of Apple LCDs started in 1984 when the Apple Flat Panel Display was introduced for the Apple IIc computer, principally to enhance the IIc's portability (see Apple IIc Portability enhancements). This monochrome display was capable of 80 columns by 24... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-Portable displays The next attempt at a flat panel was with the Macintosh Portable. More of a "luggable" than a laptop, it contained a high-resolution, active-matrix, 1-bit black & white, 9.8″ LCD with 640×400 resolution. Like the IIc Flat Panel, it was not bac... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-All-In-Ones In 1997, Apple released the Twentieth Anniversary Macintosh (TAM), its first all-in-one desktop with an LCD display. Drawing heavily from PowerBook technology, the TAM featured a 12.1″ active matrix LCD capable of displaying up to 16 bit color at 80... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-External displays The first desktop color flat-panel was introduced on March 17, 1998, with the 15″ Apple Studio Display (15-inch flat panel) which had a resolution of 1024×768. After the eMate, it was one of the first Apple products to feature translucent plas... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-The 22″ widescreen Apple Cinema Display was introduced in August 1999, simultaneously with the Power Mac G4 and in the beginning was sold only as an option to the Power Mac G4, selling for US$3,999. It had a native resolution of 1600×1024 and used a DVI connect... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-In 2000 the 22″ Cinema Displays switched to the ADC interface, and the 15″ Studio Display was remodeled to match the Cinema Display's easel-like form factor and also featured the Apple Display Connector. In 2001 an LCD-based 17″ Studio Display was introduced, w... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-In 2004 a new line was introduced, utilizing the same 20″ and 23″ panels alongside a new 30″ model, for $3,299. The displays had a sleek aluminum enclosure with a much narrower bezel than their predecessors. The 20″ model featured a 1680×1050 resolution, the 23... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-In 2006 along with the introduction of the Mac Pro, Apple lowered the price of the 30″ Cinema Display to US$1999. The Mac Pro featured an NVIDIA GeForce 7300GT as the graphics card in its base configuration which is capable of running a 30″ Cinema Display and a... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-LED Cinema Display With the introduction of the Unibody MacBook family, Apple introduced the 24-inch LED Cinema Display, its first desktop display to use the new Mini DisplayPort connector, and also the first with an LED-backlit LCD. It had built-in speakers, a... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-Thunderbolt Display In 2011 Apple released the Apple Thunderbolt Display, replacing the Mini DisplayPort and USB connector with a Thunderbolt plug for display and data. A Gigabit Ethernet port, a FireWire 800 port and a Thunderbolt 2 port were added as well, an... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-LG UltraFine After Apple discontinued production of standalone displays in 2016, they partnered with LG to design the UltraFine line, with a 21.5-inch 4K display (22MD4KA-B) and 27-inch 5K display (27MD5KA-B), released in November 2016 alongside the Thunderbolt... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Flat panel displays-Pro Display XDR Apple announced the Pro Display XDR at the 2019 WWDC, the first Apple-branded display since the Apple Thunderbolt Display was discontinued in 2016. The display contains a 6016×3384 6K color-calibrated Extreme Dynamic Range (XDR) panel.
Studio Di... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Connectors-Apple has employed a large number of display connector designs over the years: Original DA-15 (commonly but incorrectly known as a DB-15) used on all modular desktop Macs until the 1999 Blue and White Power Macintosh G3.
A 13W3 connector (as on Sun Microsystems machines... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Connectors-The Retina MacBook introduced USB-C connectivity for displays. The 2016 MacBook Pro uses a combination Thunderbolt 3 USB-C connector. They are backwards compatible with HDMI and DisplayPort.Additionally, various Apple computers have been able to output: S-video via stan... | milkshake721/2.1M-wiki-STEM |
AppleColor High-Resolution RGB Monitor-Connectors-The Retina MacBook Pro supports HDMI output from a built-in connector in addition to its two Thunderbolt connectors. | milkshake721/2.1M-wiki-STEM |
Benesi–Hildebrand method-Benesi–Hildebrand method-The Benesi–Hildebrand method is a mathematical approach used in physical chemistry for the determination of the equilibrium constant K and stoichiometry of non-bonding interactions. This method has been typically applied to reaction equilibria that form one-to-one compl... | milkshake721/2.1M-wiki-STEM |
Benesi–Hildebrand method-Benesi–Hildebrand method-HG The theoretical foundation of this method is the assumption that when either one of the reactants is present in excess amounts over the other reactant, the characteristic electronic absorption spectra of the other reactant are transparent in the collective absorption... | milkshake721/2.1M-wiki-STEM |
Benesi–Hildebrand method-History-This method was first developed by Benesi and Hildebrand in 1949, as a means to explain a phenomenon where iodine changes color in various aromatic solvents. This was attributed to the formation of an iodine-solvent complex through acid-base interactions, leading to the observed shifts ... | milkshake721/2.1M-wiki-STEM |
Benesi–Hildebrand method-Derivation-To observe one-to-one binding between a single host (H) and guest (G) using UV/Vis absorbance, the Benesi–Hildebrand method can be employed. The basis behind this method is that the acquired absorbance should be a mixture of the host, guest, and the host–guest complex.
HG +AG+AH With... | milkshake721/2.1M-wiki-STEM |
Benesi–Hildebrand method-Derivation-HG ]b A binding isotherm can be described as "the theoretical change in the concentration of one component as a function of the concentration of another component at constant temperature." This can be described by the following equation: HG ]=[H]0Ka[G]1+Ka[G] By substituting the bind... | milkshake721/2.1M-wiki-STEM |
Benesi–Hildebrand method-Derivation-ΔA=bΔε[H]0Ka[G]01+Ka[G]0 Further modifications results in an equation where a double reciprocal plot can be made with 1/ΔA as a function of 1/[G]0. Δε can be derived from the intercept while Ka can be calculated from the slope.
1ΔA=1bΔε[G]0[H]0Ka+1bΔε[H]0 | milkshake721/2.1M-wiki-STEM |
Benesi–Hildebrand method-Limitations and alternatives-In many cases, the Benesi–Hildebrand method provides excellent linear plots, and reasonable values for K and ε. However, various problems arising from experimental data have been noted from time to time. Some of these issues include: different values of ε with diffe... | milkshake721/2.1M-wiki-STEM |
Benesi–Hildebrand method-Limitations and alternatives-These limitations can be overcome by using a computational method which is more generally applicable, a non-linear least-squares minimization method. The two parameters, K or ε are determined by using the Solver module a spreadsheet, by minimizing a sum of squared d... | milkshake721/2.1M-wiki-STEM |
Benesi–Hildebrand method-Modifications-Although initially used in conjunction with UV/Vis spectroscopy, many modifications have been made that allow the B–H method to be applied to other spectroscopic techniques involving fluorescence, infrared, and NMR.Modifications have also been done to further improve the accuracy ... | milkshake721/2.1M-wiki-STEM |
Birefringence-Birefringence-Birefringence is the optical property of a material having a refractive index that depends on the polarization and propagation direction of light. These optically anisotropic materials are said to be birefringent (or birefractive). The birefringence is often quantified as the maximum differe... | milkshake721/2.1M-wiki-STEM |
Birefringence-Explanation-A mathematical description of wave propagation in a birefringent medium is presented below. Following is a qualitative explanation of the phenomenon. | milkshake721/2.1M-wiki-STEM |
Birefringence-Explanation-Uniaxial materials The simplest type of birefringence is described as uniaxial, meaning that there is a single direction governing the optical anisotropy whereas all directions perpendicular to it (or at a given angle to it) are optically equivalent. Thus rotating the material around this axis... | milkshake721/2.1M-wiki-STEM |
Birefringence-Explanation-The ordinary ray will always experience a refractive index of no, whereas the refractive index of the extraordinary ray will be in between no and ne, depending on the ray direction as described by the index ellipsoid. The magnitude of the difference is quantified by the birefringence: Δn=ne−no... | milkshake721/2.1M-wiki-STEM |
Birefringence-Explanation-The propagation (as well as reflection coefficient) of the ordinary ray is simply described by no as if there were no birefringence involved. The extraordinary ray, as its name suggests, propagates unlike any wave in an isotropic optical material. Its refraction (and reflection) at a surface c... | milkshake721/2.1M-wiki-STEM |
Birefringence-Explanation-Biaxial materials The case of so-called biaxial crystals is substantially more complex. These are characterized by three refractive indices corresponding to three principal axes of the crystal. For most ray directions, both polarizations would be classified as extraordinary rays but with diffe... | milkshake721/2.1M-wiki-STEM |
Birefringence-Explanation-The two refractive indices can be determined using the index ellipsoids for given directions of the polarization. Note that for biaxial crystals the index ellipsoid will not be an ellipsoid of revolution ("spheroid") but is described by three unequal principle refractive indices nα, nβ and nγ.... | milkshake721/2.1M-wiki-STEM |
Birefringence-Explanation-Although there is no axis of symmetry, there are two optical axes or binormals which are defined as directions along which light may propagate without birefringence, i.e., directions along which the wavelength is independent of polarization. For this reason, birefringent materials with three d... | milkshake721/2.1M-wiki-STEM |
Birefringence-Explanation-Double refraction When an arbitrary beam of light strikes the surface of a birefringent material at non-normal incidence, the polarization component normal to the optic axis (ordinary ray) and the other linear polarization (extraordinary ray) will be refracted toward somewhat different paths. ... | milkshake721/2.1M-wiki-STEM |
Birefringence-Explanation-The different angles of refraction for the two polarization components are shown in the figure at the top of this page, with the optic axis along the surface (and perpendicular to the plane of incidence), so that the angle of refraction is different for the p polarization (the "ordinary ray" i... | milkshake721/2.1M-wiki-STEM |
Birefringence-Terminology-Much of the work involving polarization preceded the understanding of light as a transverse electromagnetic wave, and this has affected some terminology in use. Isotropic materials have symmetry in all directions and the refractive index is the same for any polarization direction. An anisotrop... | milkshake721/2.1M-wiki-STEM |
Birefringence-Terminology-In a uniaxial material, one ray behaves according to the normal law of refraction (corresponding to the ordinary refractive index), so an incoming ray at normal incidence remains normal to the refracting surface. As explained above, the other polarization can deviate from normal incidence, whi... | milkshake721/2.1M-wiki-STEM |
Birefringence-Terminology-A material is termed uniaxial when it has a single direction of symmetry in its optical behavior, which we term the optic axis. It also happens to be the axis of symmetry of the index ellipsoid (a spheroid in this case). The index ellipsoid could still be described according to the refractive ... | milkshake721/2.1M-wiki-STEM |
Birefringence-Terminology-Materials in which all three refractive indices are different are termed biaxial and the origin of this term is more complicated and frequently misunderstood. In a uniaxial crystal, different polarization components of a beam will travel at different phase velocities, except for rays in the di... | milkshake721/2.1M-wiki-STEM |
Birefringence-Terminology-Fast and slow rays In a birefringent material, a wave consists of two polarization components which generally are governed by different effective refractive indices. The so-called slow ray is the component for which the material has the higher effective refractive index (slower phase velocity)... | milkshake721/2.1M-wiki-STEM |
Birefringence-Terminology-Using a thin slab of that material at normal incidence, one would implement a waveplate. In this case, there is essentially no spatial separation between the polarizations, the phase of the wave in the parallel polarization (the slow ray) will be retarded with respect to the perpendicular pola... | milkshake721/2.1M-wiki-STEM |
Birefringence-Terminology-Positive or negative Uniaxial birefringence is classified as positive when the extraordinary index of refraction ne is greater than the ordinary index no. Negative birefringence means that Δn = ne − no is less than zero. In other words, the polarization of the fast (or slow) wave is perpendicu... | milkshake721/2.1M-wiki-STEM |
Birefringence-Sources of optical birefringence-While the best known source of birefringence is the entrance of light into an anisotropic crystal, it can result in otherwise optically isotropic materials in a few ways: Stress birefringence results when a normally isotropic solid is stressed and deformed (i.e., stretched... | milkshake721/2.1M-wiki-STEM |
Birefringence-Common birefringent materials-The best characterized birefringent materials are crystals. Due to their specific crystal structures their refractive indices are well defined. Depending on the symmetry of a crystal structure (as determined by one of the 32 possible crystallographic point groups), crystals i... | milkshake721/2.1M-wiki-STEM |
Birefringence-Common birefringent materials-Cotton fiber is birefringent because of high levels of cellulosic material in the fibre's secondary cell wall which is directionally aligned with the cotton fibers. | milkshake721/2.1M-wiki-STEM |
Birefringence-Common birefringent materials-Polarized light microscopy is commonly used in biological tissue, as many biological materials are linearly or circularly birefringent. Collagen, found in cartilage, tendon, bone, corneas, and several other areas in the body, is birefringent and commonly studied with polarize... | milkshake721/2.1M-wiki-STEM |
Birefringence-Common birefringent materials-In addition to anisotropy in the electric polarizability that we have been discussing, anisotropy in the magnetic permeability could be a source of birefringence. At optical frequencies, there is no measurable magnetic polarizability (μ=μ0) of natural materials, so this is no... | milkshake721/2.1M-wiki-STEM |
Birefringence-Measurement-Birefringence and other polarization-based optical effects (such as optical rotation and linear or circular dichroism) can be observed by measuring any change in the polarization of light passing through the material. These measurements are known as polarimetry. Polarized light microscopes, wh... | milkshake721/2.1M-wiki-STEM |
Birefringence-Measurement-Birefringence measurements have been made with phase-modulated systems for examining the transient flow behaviour of fluids. Birefringence of lipid bilayers can be measured using dual-polarization interferometry. This provides a measure of the degree of order within these fluid layers and how ... | milkshake721/2.1M-wiki-STEM |
Birefringence-Applications-Birefringence is used in many optical devices. Liquid-crystal displays, the most common sort of flat-panel display, cause their pixels to become lighter or darker through rotation of the polarization (circular birefringence) of linearly polarized light as viewed through a sheet polarizer at t... | milkshake721/2.1M-wiki-STEM |
Birefringence-Applications-Birefringence also plays an important role in second-harmonic generation and other nonlinear optical components, as the crystals used for this purpose are almost always birefringent. By adjusting the angle of incidence, the effective refractive index of the extraordinary ray can be tuned in o... | milkshake721/2.1M-wiki-STEM |
Birefringence-Applications-Medicine Birefringence is utilized in medical diagnostics. One powerful accessory used with optical microscopes is a pair of crossed polarizing filters. Light from the source is polarized in the x direction after passing through the first polarizer, but above the specimen is a polarizer (a so... | milkshake721/2.1M-wiki-STEM |
Birefringence-Applications-For instance, needle aspiration of fluid from a gouty joint will reveal negatively birefringent monosodium urate crystals. Calcium pyrophosphate crystals, in contrast, show weak positive birefringence. Urate crystals appear yellow, and calcium pyrophosphate crystals appear blue when their lon... | milkshake721/2.1M-wiki-STEM |
Birefringence-Applications-The birefringence of tissue inside a living human thigh was measured using polarization-sensitive optical coherence tomography at 1310 nm and a single mode fiber in a needle. Skeletal muscle birefringence was Δn = 1.79 × 10−3± 0.18×10−3, adipose Δn = 0.07 × 10−3 ± 0.50 × 10−3, superficial apo... | milkshake721/2.1M-wiki-STEM |
Birefringence-Applications-Birefringence can be observed in amyloid plaques such as are found in the brains of Alzheimer's patients when stained with a dye such as Congo Red. Modified proteins such as immunoglobulin light chains abnormally accumulate between cells, forming fibrils. Multiple folds of these fibers line u... | milkshake721/2.1M-wiki-STEM |
Birefringence-Applications-In ophthalmology, binocular retinal birefringence screening of the Henle fibers (photoreceptor axons that go radially outward from the fovea) provides a reliable detection of strabismus and possibly also of anisometropic amblyopia. In healthy subjects, the maximum retardation induced by the H... | milkshake721/2.1M-wiki-STEM |
Birefringence-Applications-Dermatologists use dermatoscopes to view skin lesions. Dermoscopes use polarized light, allowing the user to view crystalline structures corresponding to dermal collagen in the skin. These structures may appear as shiny white lines or rosette shapes and are only visible under polarized dermos... | milkshake721/2.1M-wiki-STEM |
Birefringence-Applications-Stress-induced birefringence Isotropic solids do not exhibit birefringence. When they are under mechanical stress, birefringence results. The stress can be applied externally or is "frozen in" after a birefringent plastic ware is cooled after it is manufactured using injection molding. When s... | milkshake721/2.1M-wiki-STEM |
Birefringence-Applications-Other cases of birefringence Birefringence is observed in anisotropic elastic materials. In these materials, the two polarizations split according to their effective refractive indices, which are also sensitive to stress.
The study of birefringence in shear waves traveling through the solid E... | milkshake721/2.1M-wiki-STEM |
Birefringence-Theory-In an isotropic medium (including free space) the so-called electric displacement (D) is just proportional to the electric field (E) according to D = ɛE where the material's permittivity ε is just a scalar (and equal to n2ε0 where n is the index of refraction). In an anisotropic material exhibiting... | milkshake721/2.1M-wiki-STEM |
Birefringence-Theory-Finding the allowed values of k for a given ω is easiest done by using Cartesian coordinates with the x, y and z axes chosen in the directions of the symmetry axes of the crystal (or simply choosing z in the direction of the optic axis of a uniaxial crystal), resulting in a diagonal matrix for the ... | milkshake721/2.1M-wiki-STEM |
Birefringence-Theory-For a biaxial material a similar but more complicated condition on the two waves can be described; the locus of allowed k vectors (the wavevector surface) is a 4th-degree two-sheeted surface, so that in a given direction there are generally two permitted k vectors (and their opposites). By inspecti... | milkshake721/2.1M-wiki-STEM |
Birefringence-Theory-When those two propagation constants are equal then the effective refractive index is independent of polarization, and there is consequently no birefringence encountered by a wave traveling in that particular direction. For a uniaxial crystal, this is the optic axis, the ±z direction according to t... | milkshake721/2.1M-wiki-STEM |
Birefringence-Theory-A general state of polarization launched into the medium can always be decomposed into two waves, one in each of those two polarizations, which will then propagate with different wavenumbers |k|. Applying the different phase of propagation to those two waves over a specified propagation distance wi... | milkshake721/2.1M-wiki-STEM |
Birefringence-Theory-In the more general case, there is a difference not only in the magnitude but the direction of the two rays. For instance, the photograph through a calcite crystal (top of page) shows a shifted image in the two polarizations; this is due to the optic axis being neither parallel nor normal to the cr... | milkshake721/2.1M-wiki-STEM |
Vacuum blasting-Vacuum blasting-Vacuum blasting is an abrasive blasting method, also referred to as dustless blasting or closed loop abrasive blasting. The method is characterized by a blast tool that does abrasive blasting and collects both used blast media, and loosened particles from the surface to be treated, simul... | milkshake721/2.1M-wiki-STEM |
Vacuum blasting-Procedure-The blast tool is equipped with a blast hose and a suction hose, that both run from the blast tool to a control unit. The control unit supplies the blast tool with pressurized air mixed with blast media, and sucks back dust, loosened particles and used blast media. The control unit continuous... | milkshake721/2.1M-wiki-STEM |
Vacuum blasting-Applications-The method is typically used in areas where dust and spill from regular abrasive blasting is not wanted, for example due to HSE-considerations. The blast process itself is slower than regular abrasive blasting, but requires less sheeting and scaffolding | milkshake721/2.1M-wiki-STEM |
Myogel-Myogel-Myogel is a trade name for a human-based extracellular matrix used in cancer research to provide a 3D cell culture environment for cancer cells. Unlike other synthesized matrices such as matrigel which originated from mice sarcoma, myogel is extracted from a human benign tumor tissue called leiomyoma. Myo... | milkshake721/2.1M-wiki-STEM |
Irene Tracey-Irene Tracey-Irene Mary Carmel Tracey (born 30 October 1966) is Vice-Chancellor of the University of Oxford and former Warden of Merton College, Oxford. She is also Professor of Anaesthetic Neuroscience in the Nuffield Department of Clinical Neurosciences and formerly Pro-Vice-Chancellor (without portfolio... | milkshake721/2.1M-wiki-STEM |
Irene Tracey-Early life and education-Tracey was born at the Radcliffe Infirmary in Oxford and educated at St. Thomas More R.C. Primary School and Gosford Hill School in Kidlington. She completed her undergraduate and graduate studies at Merton College, Oxford in Biochemistry under the supervision of Eric Newsholme and... | milkshake721/2.1M-wiki-STEM |
Irene Tracey-Career-As an early career researcher, Tracey held a postdoctoral position at Harvard Medical School, working at the MGH-NMR imaging centre (now Martinos) applying magnetic spectroscopy techniques to understand AIDS Dementia Complex. During this period she became interested in pain, the research field she w... | milkshake721/2.1M-wiki-STEM |
Irene Tracey-Career-Research Tracey's research centers on investigating what she calls "the cerebral signature for pain perception" − how key regions of the human brain give rise to pain − and on developing objective, reliable, scientific ways of measuring what has always been considered a highly subjective experience.... | milkshake721/2.1M-wiki-STEM |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.