p131
... Infrared (IR) Spectroscopy is the absorption measurement of different IR frequencies by a sample placed in the path of an IR beam. At temperatures above absolute zero, all the atoms in molecules are in continuous vibration with respect to each other. When the frequency of a specific vibration is equ ...
... Infrared (IR) Spectroscopy is the absorption measurement of different IR frequencies by a sample placed in the path of an IR beam. At temperatures above absolute zero, all the atoms in molecules are in continuous vibration with respect to each other. When the frequency of a specific vibration is equ ...
Biological X-ray absorption spectroscopy (BioXAS): a valuable tool
... local to the metal environment, BioXAS is a valuable ally of computational chemistry. There has been progress in recent years in developing theoretical methods to study protein structures locally at metal-binding sites and at locations of catalytic activity [24,25]. Recent applications combining XAS ...
... local to the metal environment, BioXAS is a valuable ally of computational chemistry. There has been progress in recent years in developing theoretical methods to study protein structures locally at metal-binding sites and at locations of catalytic activity [24,25]. Recent applications combining XAS ...
Physical Properties used in Mineral Identification
... formed by deposition from mineral-bearing waters dripping from the roofs of caverns 2. Concentric—more or less spherical layers superimposed upon one another about a common center 3. Pisolitic—rounded masses about the size of peas 4. Oolitic—a mineral aggregate formed of small spheres resembling fis ...
... formed by deposition from mineral-bearing waters dripping from the roofs of caverns 2. Concentric—more or less spherical layers superimposed upon one another about a common center 3. Pisolitic—rounded masses about the size of peas 4. Oolitic—a mineral aggregate formed of small spheres resembling fis ...
Precision Electron Diffraction Structure Analysis and Its Use in
... and surface layers. It is important that the objects for electron diffraction studies—thin films—are prepared much easier than single crystals and that diffusion and relaxation processes in thin films proceed much faster than in the specimens conventionally used in X-ray and neutron diffraction stud ...
... and surface layers. It is important that the objects for electron diffraction studies—thin films—are prepared much easier than single crystals and that diffusion and relaxation processes in thin films proceed much faster than in the specimens conventionally used in X-ray and neutron diffraction stud ...
T-Shaped Molecular Building Units in the Porous Structure of Ag(4,4
... molecular building units has yielded a remarkable class of materials having diverse architecture and functions.1 These include metal-organic solids with open frameworks having zeolite-like attributes2 and others having important electronic3 and magnetic4 properties. One of the simplest strategies em ...
... molecular building units has yielded a remarkable class of materials having diverse architecture and functions.1 These include metal-organic solids with open frameworks having zeolite-like attributes2 and others having important electronic3 and magnetic4 properties. One of the simplest strategies em ...
Applications of Random Nonlinear Photonic Crystals Based
... the linear optical properties of a material, the first change being within its refractive index. In this case, the interference of electromagnetic waves reflected within the material due to steps of refractive index strongly modifies the spectral dependence of reflection and transmission coefficient ...
... the linear optical properties of a material, the first change being within its refractive index. In this case, the interference of electromagnetic waves reflected within the material due to steps of refractive index strongly modifies the spectral dependence of reflection and transmission coefficient ...
- Alagappa University
... mechanism of growing single crystals by molecular beam method. Is it possible to grow all materials as single crystals using this technique? Explain. ...
... mechanism of growing single crystals by molecular beam method. Is it possible to grow all materials as single crystals using this technique? Explain. ...
Minerals
... the strictest sense because its atoms are not all arranged in a definite, repeating pattern, even though it is a naturally occurring, inorganic solid. ...
... the strictest sense because its atoms are not all arranged in a definite, repeating pattern, even though it is a naturally occurring, inorganic solid. ...
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... of equilibrium with respect to the component B to the cathode direction in comparison with the value of Eeq in the GaAs−H2O system he was offered to introduce a correction for reversibility into the potential-determining reaction of uniform (pseudoselective) destruction of compound, taking into acco ...
... of equilibrium with respect to the component B to the cathode direction in comparison with the value of Eeq in the GaAs−H2O system he was offered to introduce a correction for reversibility into the potential-determining reaction of uniform (pseudoselective) destruction of compound, taking into acco ...
Chapter 8 – Symmetry in Crystal Physics – p. 1
... Must be fulfilled for all transformation matrices aij corresponding to symmetry operations of the point group of the crystal (crystal class) (remark: in general, it is not necessary to test all symmetry operations, but only the set of generating operations of the point group). Neumann’s principle ma ...
... Must be fulfilled for all transformation matrices aij corresponding to symmetry operations of the point group of the crystal (crystal class) (remark: in general, it is not necessary to test all symmetry operations, but only the set of generating operations of the point group). Neumann’s principle ma ...
Inhibited Spontaneous Emission of Quantum Dots Observed in a 3D
... frequency range for which light is forbidden for all wave vectors and all polarizations [3]. Such band gaps are expected in 3D photonic crystals, i.e., dielectric nanostructures with periodicities less than half the optical wavelength [4]. Anticipated cavity QED effects of band gaps include complete ...
... frequency range for which light is forbidden for all wave vectors and all polarizations [3]. Such band gaps are expected in 3D photonic crystals, i.e., dielectric nanostructures with periodicities less than half the optical wavelength [4]. Anticipated cavity QED effects of band gaps include complete ...
Crystal Structure of Hyaluronidase, a Major Allergen of Bee Venom
... in the structure of quinolinic acid phosphoribosyltransferase (QAPRTase) [29]. Here, the gap that occurs between strands 2 and 3 is partially occupied by the substrate. In Hya there are no hydrogen bonds between strands 1 and 2 whereas in QAPRTase the analogous strands interact through a single hydr ...
... in the structure of quinolinic acid phosphoribosyltransferase (QAPRTase) [29]. Here, the gap that occurs between strands 2 and 3 is partially occupied by the substrate. In Hya there are no hydrogen bonds between strands 1 and 2 whereas in QAPRTase the analogous strands interact through a single hydr ...
Gemmology Course Outline Lewton-Brain ©86/95/10
... A perfect crystal is bounded by plane faces which meet at angles specific for each kind of material (angle analysis can identify minerals). A crystal may be cleaved in directions related to the external form or to a possible crystal form for the mineral. Sometimes two distinct minerals can have the ...
... A perfect crystal is bounded by plane faces which meet at angles specific for each kind of material (angle analysis can identify minerals). A crystal may be cleaved in directions related to the external form or to a possible crystal form for the mineral. Sometimes two distinct minerals can have the ...
Nucleic acid crystallography: current progress
... (such repetitive regions are encountered throughout the genomes of all vertebrates), whereby two quadruplexes associate into an octaplex under formation of four central G-tetrad layers. An unusual form of self-association is also seen in the structure of d(GCATGCT). Two strands fold into a complemen ...
... (such repetitive regions are encountered throughout the genomes of all vertebrates), whereby two quadruplexes associate into an octaplex under formation of four central G-tetrad layers. An unusual form of self-association is also seen in the structure of d(GCATGCT). Two strands fold into a complemen ...
Structural studies of protein arginine methyltransferase 2 reveals its
... crystallized. The first crystals were obtained from a full-length construct (zPRMT21-408) in the presence of sinefungin, a natural inhibitor. The structure was resolution (Table 1). The solved and refined at 2.45 A electron density map revealed the absence of residues 1–71 corresponding to the N-t ...
... crystallized. The first crystals were obtained from a full-length construct (zPRMT21-408) in the presence of sinefungin, a natural inhibitor. The structure was resolution (Table 1). The solved and refined at 2.45 A electron density map revealed the absence of residues 1–71 corresponding to the N-t ...
Advances in Structural and Functional Analysis of Membrane
... Here we describe recent technical and methodological progress aimed at automating electron crystallography and streamlining structure determination by this technique. Structure determination by electron crystallography can be lengthy and challenging. Major bottlenecks include sample preparation, cry ...
... Here we describe recent technical and methodological progress aimed at automating electron crystallography and streamlining structure determination by this technique. Structure determination by electron crystallography can be lengthy and challenging. Major bottlenecks include sample preparation, cry ...
RCSB Molecule of the Month - Tetrahydrobiopterin Biosynthesis
... Enzymes that perform unusual chemical reactions often need some assistance. The twenty natural amino acids have many different chemical properties that may be used to catalyze chemical reactions, but sometimes amino acids just aren't enough. In these cases, cofactors with special chemical properties ...
... Enzymes that perform unusual chemical reactions often need some assistance. The twenty natural amino acids have many different chemical properties that may be used to catalyze chemical reactions, but sometimes amino acids just aren't enough. In these cases, cofactors with special chemical properties ...
Structure of c-Phycocyanin from the Thermophilic
... sequence is manifested in the similar three-dimensional structures. The overall chain fold shows the typical phycobiliprotein eight a-helical, globin-like structure (Figure 2). The re®ned Sv-PC structure is well within all geometric criteria. The rms deviÊ and ation for bond lengths and angles is 0. ...
... sequence is manifested in the similar three-dimensional structures. The overall chain fold shows the typical phycobiliprotein eight a-helical, globin-like structure (Figure 2). The re®ned Sv-PC structure is well within all geometric criteria. The rms deviÊ and ation for bond lengths and angles is 0. ...
Lecture 32: Carbonates and Phosphates
... The carbonates make up the fourth largest subset of the general grouping of carbonates, nitrates, borates, sulphates, chromates, t tungstates, molybdates, phosphates, arsenates and vanadates. t t l bd t h h t t d d t This general grouping comes from the Dana Classification system. It is a well es ...
... The carbonates make up the fourth largest subset of the general grouping of carbonates, nitrates, borates, sulphates, chromates, t tungstates, molybdates, phosphates, arsenates and vanadates. t t l bd t h h t t d d t This general grouping comes from the Dana Classification system. It is a well es ...
Parametric generation of tunable infrared radiation in
... materials for parametric devices in the middle IR region of the spectrum because of their wide transparency range and large second-order nonlinearities. However, the first demonstration of parametric generation in these crystals was reported only recently.' 4 This is connected with considerable impr ...
... materials for parametric devices in the middle IR region of the spectrum because of their wide transparency range and large second-order nonlinearities. However, the first demonstration of parametric generation in these crystals was reported only recently.' 4 This is connected with considerable impr ...
Chapter 8: Major Elements
... Uniaxial indicatrix can be positive (prolate or ‘rugby ball’) or negative (oblate or ‘smartie’) ...
... Uniaxial indicatrix can be positive (prolate or ‘rugby ball’) or negative (oblate or ‘smartie’) ...
Physical Properties of Minerals
... Concentric, Colloform, Stalactitic, Fibrous, ….. etc. (Fig. 6). Could give some clues about the conditions of crystallization. 14- Twinning: During the crystallization of a mineral, several crystals (of the same mineral) may grow together either in a parallel fashion (known as parallel intergrowth, ...
... Concentric, Colloform, Stalactitic, Fibrous, ….. etc. (Fig. 6). Could give some clues about the conditions of crystallization. 14- Twinning: During the crystallization of a mineral, several crystals (of the same mineral) may grow together either in a parallel fashion (known as parallel intergrowth, ...
Nonlinear Optical Effects in Photonic Crystals Abstract
... people observed a large enhancement of degenerate four-wave mixing efficiency8. Since the total thickness of the whole structure is only a few micrometers, it was successfully used to form an optical phase-conjugated image. Similarly, if you fill the defects in 1D PhCs with nonlinear organic dye, yo ...
... people observed a large enhancement of degenerate four-wave mixing efficiency8. Since the total thickness of the whole structure is only a few micrometers, it was successfully used to form an optical phase-conjugated image. Similarly, if you fill the defects in 1D PhCs with nonlinear organic dye, yo ...
The Refined Crystal Structure of an Eel Pout Type III
... 1991) were used in computational least-square refinement and in manual modifications of the model according to the electron density maps. The model after preliminary refinement yielded an R-value of 0.17 at 1.0 Å resolution. It contained all 64 amino acid residues and 92 water molecules. All temper ...
... 1991) were used in computational least-square refinement and in manual modifications of the model according to the electron density maps. The model after preliminary refinement yielded an R-value of 0.17 at 1.0 Å resolution. It contained all 64 amino acid residues and 92 water molecules. All temper ...
Crystallographic studies of two bacterial antibiotic resistance enzymes
... provide resistance to an array of antibiotics. Both enzymes are part of a growing resistance problem in the medical world. In order to overcome the ever-growing arsenal of antibioticresistance enzymes, it is necessary to understand the molecular basis of their action. Accurate structures of these pr ...
... provide resistance to an array of antibiotics. Both enzymes are part of a growing resistance problem in the medical world. In order to overcome the ever-growing arsenal of antibioticresistance enzymes, it is necessary to understand the molecular basis of their action. Accurate structures of these pr ...
Crystallographic database
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 directionally dependent physical properties. A crystal structure describes the arrangement of atoms, ions, or molecules in a crystal. (Molecules need to crystallize into solids so that their regularly repeating arrangements can be taken advantage of in X-ray, neutron, and electron diffraction based crystallography.)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-diffraction fingerprinting databases.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 databases specializing in nanocrystals and can be identified by comparing zone axis subsets in lattice-fringe fingerprint plots with entries in a lattice-fringe fingerprinting database.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 Information File (CIF) as a universal data exchange format.