Design and Synthesis of Microporous Dipeptide Structures and
... proteinogenic amino acids have been synthesized, crystallized and analyzed by single crystal X-ray diffraction methods. The majority of these dipeptides were obtained as porous structures. As nanoporous materials, a few of these dipeptides were studied for CO2 and methane gas absorption and selectiv ...
... proteinogenic amino acids have been synthesized, crystallized and analyzed by single crystal X-ray diffraction methods. The majority of these dipeptides were obtained as porous structures. As nanoporous materials, a few of these dipeptides were studied for CO2 and methane gas absorption and selectiv ...
university of oslo
... of oxides worldwide, not least because it contained a comprehensive review of defect structure and defect-related properties of all binary metal oxides. It followed Kofstad's equally well-recognized book "High temperature oxidation of metals" from 1966, later revised and published under the title "H ...
... of oxides worldwide, not least because it contained a comprehensive review of defect structure and defect-related properties of all binary metal oxides. It followed Kofstad's equally well-recognized book "High temperature oxidation of metals" from 1966, later revised and published under the title "H ...
Asp_calcite_FCM_Main_NatMat_Symplectic author accepted
... block of calcite (34x44x34 Å3) with 864 CaCO3 formula units and two charge states of each amino acid (Asp2-, Asp1-, Gly1- and Gly0) were considered as the pKa values of the amino acids were close to experimental pH values (Supplementary Fig. 7). The amino acids were inserted by first removing Ca2+ ...
... block of calcite (34x44x34 Å3) with 864 CaCO3 formula units and two charge states of each amino acid (Asp2-, Asp1-, Gly1- and Gly0) were considered as the pKa values of the amino acids were close to experimental pH values (Supplementary Fig. 7). The amino acids were inserted by first removing Ca2+ ...
THE ALKALI FELDSPARS VI. SANIDINE AND ORTHOCLASE
... the determinationson grains, thin sectionswere much the more satis{actory, particularly as variation within single crystals could be detected and correlated with morphological features. An accuracy of about 2o was obtained in the valueslisted in Table 3. From the separatedphenocrystsabout forty frag ...
... the determinationson grains, thin sectionswere much the more satis{actory, particularly as variation within single crystals could be detected and correlated with morphological features. An accuracy of about 2o was obtained in the valueslisted in Table 3. From the separatedphenocrystsabout forty frag ...
Photonic Crystal Fibers
... Photonic crystal fibers are a new class of optical fibers. Their artificial crystal-like microstructure results in a number of unusual properties. They can guide light not only through a well-known total internal reflection mechanism but using also photonic bandgap effect. In this paper different pr ...
... Photonic crystal fibers are a new class of optical fibers. Their artificial crystal-like microstructure results in a number of unusual properties. They can guide light not only through a well-known total internal reflection mechanism but using also photonic bandgap effect. In this paper different pr ...
structural and luminescence properties of magnesium strontium
... The long after glow phosphor is a special property in luminescence field o f research. It can maintain the phosphorescence for several hours at room temperature. In the early time, zinc sulphide doped cobalt and copper (ZnS: Cu, Co) was considered the main phosphorescent materials. However, it has a ...
... The long after glow phosphor is a special property in luminescence field o f research. It can maintain the phosphorescence for several hours at room temperature. In the early time, zinc sulphide doped cobalt and copper (ZnS: Cu, Co) was considered the main phosphorescent materials. However, it has a ...
in Nanotube Walls - American Chemical Society
... coverage of the oven was removed. To prepare PVDF nanotubes by melt-wetting, the templates were placed in the oven in an argon atmosphere. Then, we placed PVDF pellets with tweezers on the template at temperatures of 200 or 215 °C, well above its melting point of 178 °C. To prepare PVDF nanotubes by ...
... coverage of the oven was removed. To prepare PVDF nanotubes by melt-wetting, the templates were placed in the oven in an argon atmosphere. Then, we placed PVDF pellets with tweezers on the template at temperatures of 200 or 215 °C, well above its melting point of 178 °C. To prepare PVDF nanotubes by ...
Magmatic Differentiation
... intermediate composition (cf. mixing lines on variation diagrams). The effects of this mechanism are most obvious if one magma is basic and the other is acidic, where the basic one will tend to cool and crystallize, while the acidic one will be superheated. For magma mixing to occur, both magmas hav ...
... intermediate composition (cf. mixing lines on variation diagrams). The effects of this mechanism are most obvious if one magma is basic and the other is acidic, where the basic one will tend to cool and crystallize, while the acidic one will be superheated. For magma mixing to occur, both magmas hav ...
Calcium sulfate crystallization in phosphoric acid
... later work has shown that large deviations from the t.L Law occur if dif fusion controls crystal growth. In an article by Saeman (30) the theoretical size distribution in a mixed suspension without classified discharge is derived, assuming growth rate as a function of supersaturation only. ...
... later work has shown that large deviations from the t.L Law occur if dif fusion controls crystal growth. In an article by Saeman (30) the theoretical size distribution in a mixed suspension without classified discharge is derived, assuming growth rate as a function of supersaturation only. ...
Photonic crystals cause active colour change in chameleons
... in the near-infrared range is substantially and systematically higher in chameleons than in other lizards. It is noteworthy that the iridophores found in non-chameleonid lizards can exhibit guanine crystals with diverse sizes, shapes and organizations (some of which generate structural colours14) bu ...
... in the near-infrared range is substantially and systematically higher in chameleons than in other lizards. It is noteworthy that the iridophores found in non-chameleonid lizards can exhibit guanine crystals with diverse sizes, shapes and organizations (some of which generate structural colours14) bu ...
Topological studies of three related MOFs of Gd(III) and 5
... 2010). These structures may have additional strength through hydrogen bonds. The nitro group is not usually found to coordinate but acts as a hydrogen bond acceptor and these compounds have been found to possess good chemical and thermal stability (Chen et al., 2010). Isophthalic acid has been found ...
... 2010). These structures may have additional strength through hydrogen bonds. The nitro group is not usually found to coordinate but acts as a hydrogen bond acceptor and these compounds have been found to possess good chemical and thermal stability (Chen et al., 2010). Isophthalic acid has been found ...
Occurrence, types and distribution of calcium oxalate crystals in
... Although there have been numerous studies on calcium oxalate crystals in plants, only a few studies (Fasset 1973; Doaigey 1991) have been carried out to investigate the relationship between calcium oxalate crystals and toxicity of plants. Therefore, in the present study, types and specific locations ...
... Although there have been numerous studies on calcium oxalate crystals in plants, only a few studies (Fasset 1973; Doaigey 1991) have been carried out to investigate the relationship between calcium oxalate crystals and toxicity of plants. Therefore, in the present study, types and specific locations ...
What Is a Mineral?
... Mineral Identification When you begin teaching this section, give pairs of students an unknown mineral. Tell students that their goal will be to identify the mineral by the time the class finishes studying the chapter and to present a short report on the mineral to the class. Their reports should in ...
... Mineral Identification When you begin teaching this section, give pairs of students an unknown mineral. Tell students that their goal will be to identify the mineral by the time the class finishes studying the chapter and to present a short report on the mineral to the class. Their reports should in ...
electronic reprint Structure of a new crystal form of
... The only non-covalent contacts seen between the two ubiquitin moieties of the asymmetric unit of Ub4-2 are one hydrogen bond between Gln40 N"2 and Ê ) and one van Ala146 O (3.0 A der Waals contact between the side chains of Arg74 and Asn160 Ê between Arg74 C and (3.4 A Asn160 C ). These limited int ...
... The only non-covalent contacts seen between the two ubiquitin moieties of the asymmetric unit of Ub4-2 are one hydrogen bond between Gln40 N"2 and Ê ) and one van Ala146 O (3.0 A der Waals contact between the side chains of Arg74 and Asn160 Ê between Arg74 C and (3.4 A Asn160 C ). These limited int ...
Magnetite from magnetotactic bacteria: Size distributions and twinning
... reliable criteria for distinguishing biogenic from nonbiogenic magnetite have not been developed. In the present study, we compare the structural characteristics of BCM magnetite produced by magnetotactic bacteria with nonbiogenic magnetite of similar mean size. We used several pure cultured strains ...
... reliable criteria for distinguishing biogenic from nonbiogenic magnetite have not been developed. In the present study, we compare the structural characteristics of BCM magnetite produced by magnetotactic bacteria with nonbiogenic magnetite of similar mean size. We used several pure cultured strains ...
2.1T - Introduction to Minerals Teacher
... inorganic. This means that they did not come from a living organism. Some minerals form by organic means and inorganic means. For example, calcite forms both organically and inorganically. ...
... inorganic. This means that they did not come from a living organism. Some minerals form by organic means and inorganic means. For example, calcite forms both organically and inorganically. ...
Theoretical studies of light propagation in photonic and plasmonic devices Link¨
... and, finally, the need of novel materials. In this regard, the most promising ”building blocks” of modern photonics are photonic crystals, lasing microcavities and plasmonic devices, which, being intensively studied during the latest decade, can provide the required functionality and microminiaturiz ...
... and, finally, the need of novel materials. In this regard, the most promising ”building blocks” of modern photonics are photonic crystals, lasing microcavities and plasmonic devices, which, being intensively studied during the latest decade, can provide the required functionality and microminiaturiz ...
as PDF
... where the applied external force F (t) is due to the pumping laser pulse. All the existing mechanisms used to describe the excitation of coherent phonon are focussed on the expression of the driving force. We can distinguish mainly three mechanisms, the impulsive stimulated Raman scattering (ISRS) ( ...
... where the applied external force F (t) is due to the pumping laser pulse. All the existing mechanisms used to describe the excitation of coherent phonon are focussed on the expression of the driving force. We can distinguish mainly three mechanisms, the impulsive stimulated Raman scattering (ISRS) ( ...
Cell-Mediated Crystallization of Calcium Oxalate in
... specialized cells that store calcium oxalate. Cell-specific synthesis and accumulation of these chambers signify the differentiation of a crystal-forming cell early in its development (Arnott and Pautard, 1970; Frank and Jensen, 1970; Horner and Whitmoyer, 1972; Franceschi, 1984; Kausch and Horner, ...
... specialized cells that store calcium oxalate. Cell-specific synthesis and accumulation of these chambers signify the differentiation of a crystal-forming cell early in its development (Arnott and Pautard, 1970; Frank and Jensen, 1970; Horner and Whitmoyer, 1972; Franceschi, 1984; Kausch and Horner, ...
Synthesis and characterization of pure and doped ZnO
... chemical reaction method. XRD and SEM analysis confirmed the formation of single phase nanoparticles of pure and doped ZnO. The Rietveld analysis of XRD pattern showed only the presence of pure wurtzite crystal structure in all the samples with an average particle size of about 40nm, which may find ...
... chemical reaction method. XRD and SEM analysis confirmed the formation of single phase nanoparticles of pure and doped ZnO. The Rietveld analysis of XRD pattern showed only the presence of pure wurtzite crystal structure in all the samples with an average particle size of about 40nm, which may find ...
Chapter 3: Minerals and Matter
... Polymorphs • Two or more minerals with the same chemical composition but different crystalline structures • Diamond and graphite are good examples of polymorphs – The transformation of one polymorph to another is called a phase change ...
... Polymorphs • Two or more minerals with the same chemical composition but different crystalline structures • Diamond and graphite are good examples of polymorphs – The transformation of one polymorph to another is called a phase change ...
The solidification of a disk-shaped crystal from a weakly
... constant potential. Thus, knowing the capacitance of a thin disk and assuming its thickness evolves slowly, the radial growth rate can be estimated. The analogy assumes that the disk is perfectly conducting (which is a good approximation for ice growth from the vapour phase but not the liquid phase) ...
... constant potential. Thus, knowing the capacitance of a thin disk and assuming its thickness evolves slowly, the radial growth rate can be estimated. The analogy assumes that the disk is perfectly conducting (which is a good approximation for ice growth from the vapour phase but not the liquid phase) ...
Chapter 2 Lecture PowerPoint Handout
... • An isotope is an atom that exhibits variation in its mass number (same # protons with different # neutrons) • Some isotopes have unstable nuclei that emit particles and energy in a process known as radioactive decay ...
... • An isotope is an atom that exhibits variation in its mass number (same # protons with different # neutrons) • Some isotopes have unstable nuclei that emit particles and energy in a process known as radioactive decay ...
Volcanoes and Igneous Activity Earth
... An isotope is an atom that exhibits variation in its mass number Some isotopes have unstable nuclei that emit particles and energy in a process known as radioactive decay ...
... An isotope is an atom that exhibits variation in its mass number Some isotopes have unstable nuclei that emit particles and energy in a process known as radioactive decay ...
Minerals
... An isotope is an atom that exhibits variation in its mass number Some isotopes have unstable nuclei that emit particles and energy in a process known as radioactive decay ...
... An isotope is an atom that exhibits variation in its mass number Some isotopes have unstable nuclei that emit particles and energy in a process known as radioactive decay ...
X-ray crystallography
X-ray crystallography is a tool used for identifying the atomic and molecular structure of a crystal, in which the crystalline atoms cause a beam of incident X-rays to diffract into many specific directions. By measuring the angles and intensities of these diffracted beams, a crystallographer can produce a three-dimensional picture of the density of electrons within the crystal. From this electron density, the mean positions of the atoms in the crystal can be determined, as well as their chemical bonds, their disorder and various other information.Since many materials can form crystals—such as salts, metals, minerals, semiconductors, as well as various inorganic, organic and biological molecules—X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences among various materials, especially minerals and alloys. The method also revealed the structure and function of many biological molecules, including vitamins, drugs, proteins and nucleic acids such as DNA. X-ray crystallography is still the chief method for characterizing the atomic structure of new materials and in discerning materials that appear similar by other experiments. X-ray crystal structures can also account for unusual electronic or elastic properties of a material, shed light on chemical interactions and processes, or serve as the basis for designing pharmaceuticals against diseases.In a single-crystal X-ray diffraction measurement, a crystal is mounted on a goniometer. The goniometer is used to position the crystal at selected orientations. The crystal is bombarded with a finely focused monochromatic beam of X-rays, producing a diffraction pattern of regularly spaced spots known as reflections. The two-dimensional images taken at different rotations are converted into a three-dimensional model of the density of electrons within the crystal using the mathematical method of Fourier transforms, combined with chemical data known for the sample. Poor resolution (fuzziness) or even errors may result if the crystals are too small, or not uniform enough in their internal makeup.X-ray crystallography is related to several other methods for determining atomic structures. Similar diffraction patterns can be produced by scattering electrons or neutrons, which are likewise interpreted by Fourier transformation. If single crystals of sufficient size cannot be obtained, various other X-ray methods can be applied to obtain less detailed information; such methods include fiber diffraction, powder diffraction and (if the sample is not crystallized) small-angle X-ray scattering (SAXS).If the material under investigation is only available in the form of nanocrystalline powders or suffers from poor crystallinity, the methods of electron crystallography can be applied for determining the atomic structure.For all above mentioned X-ray diffraction methods, the scattering is elastic; the scattered X-rays have the same wavelength as the incoming X-ray. By contrast, inelastic X-ray scattering methods are useful in studying excitations of the sample, rather than the distribution of its atoms.