Physical Properties of Minerals
... element (chromophore) in which the orbital energies have been affected by crystallization (known as the crystal field effect or crystal field splitting; Fig. 1). With some empty orbitals, electrons can absorb certain wavelengths of the visible spectrum to jump to the next empty orbital, hence render ...
... element (chromophore) in which the orbital energies have been affected by crystallization (known as the crystal field effect or crystal field splitting; Fig. 1). With some empty orbitals, electrons can absorb certain wavelengths of the visible spectrum to jump to the next empty orbital, hence render ...
Atom
... and gases. In other words, it is the smallest particle of an element that possesses the chemical and physical properties of that element. Element: An "element" is a substance that cannot be broken down into substances of simpler composition any further by chemical reactions. It is composed entirely ...
... and gases. In other words, it is the smallest particle of an element that possesses the chemical and physical properties of that element. Element: An "element" is a substance that cannot be broken down into substances of simpler composition any further by chemical reactions. It is composed entirely ...
MINERALS
... different kinds of minerals • Most are made of combinations of elements (compounds) ...
... different kinds of minerals • Most are made of combinations of elements (compounds) ...
Structural position of H2O molecules and hydrogen bonding in
... basis of their basal spacing: 14 Å tobermorite [plombierite, Ca5Si6O16(OH)2·7H2O], 11 Å tobermorite with a variable composition in the interlayer [Ca5–xSi6O17–2x(OH)2x·5H2O] and H2O-free 9 Å tobermorite [Ca5Si6O16(OH)2, riversideite]. Upon heating to about 353–373 K the 14 Å tobermorite transforms i ...
... basis of their basal spacing: 14 Å tobermorite [plombierite, Ca5Si6O16(OH)2·7H2O], 11 Å tobermorite with a variable composition in the interlayer [Ca5–xSi6O17–2x(OH)2x·5H2O] and H2O-free 9 Å tobermorite [Ca5Si6O16(OH)2, riversideite]. Upon heating to about 353–373 K the 14 Å tobermorite transforms i ...
Principles of Crystal Chemistry
... distorted. This is necessary to minimize cation – cation repulsion. Rule 5: The number of essential sites in a crystal structure that are substantially different (i.e. with differences in size and coordination) tends to be small. On the other hand, many of these sites may be occupied by different io ...
... distorted. This is necessary to minimize cation – cation repulsion. Rule 5: The number of essential sites in a crystal structure that are substantially different (i.e. with differences in size and coordination) tends to be small. On the other hand, many of these sites may be occupied by different io ...
Structure and magnetic behaviour of mononuclear and dinuclear Cu(II)/Zn(II) monocarboxylate-pyridine
... Materials and methods. Copper(II) formate tetrahydrate, Zn(II) nitrate hexahydrate, and benzoic acid were purchased from Wako Chemical Company. All other organic ligands were purchased from Tokyo Kasei Chemical Company and used as received without further purification. Elemental microanalyses of the ...
... Materials and methods. Copper(II) formate tetrahydrate, Zn(II) nitrate hexahydrate, and benzoic acid were purchased from Wako Chemical Company. All other organic ligands were purchased from Tokyo Kasei Chemical Company and used as received without further purification. Elemental microanalyses of the ...
Second-harmonic generation of focused ultrashort
... propagation direction of each beam. k and η are the wave vector and impedance inside the material, respectively, ω0 is the pump central angular frequency, and v g is the group velocity. In the hard x-ray regime, high above resonances, the linear interaction is described by Thomson scattering giving ...
... propagation direction of each beam. k and η are the wave vector and impedance inside the material, respectively, ω0 is the pump central angular frequency, and v g is the group velocity. In the hard x-ray regime, high above resonances, the linear interaction is described by Thomson scattering giving ...
1 - SUrface
... further supports our assertion that O(3) originates from a solvated water molecule.17 BVS analyzes the bond distances to a particular atom, providing information on bonding and can be used to determine if bonds are absent for a structure. Analysis of O(1) and O(2) [ligand oxygen atoms] indicated tha ...
... further supports our assertion that O(3) originates from a solvated water molecule.17 BVS analyzes the bond distances to a particular atom, providing information on bonding and can be used to determine if bonds are absent for a structure. Analysis of O(1) and O(2) [ligand oxygen atoms] indicated tha ...
Minerals - CoconinoHighSchool
... Calcium carbonate, or CaCO3, comprises more than 4% of the earth’s crust and is found throughout the world. Its most common natural forms are chalk, limestone, and marble, produced by the sedimentation of the shells of small fossilized snails, shellfish, and coral over millions of years. Although al ...
... Calcium carbonate, or CaCO3, comprises more than 4% of the earth’s crust and is found throughout the world. Its most common natural forms are chalk, limestone, and marble, produced by the sedimentation of the shells of small fossilized snails, shellfish, and coral over millions of years. Although al ...
Introduction to Attenuated Total Internal Reflectance
... The material which is most commonly used for ATR spectroscopy is ZnSe. ZnSe has a refractive index of 2.4 making it suitable for most organic materials and it has a transmission range from 20,000 to 650 cm-1 . This material is insoluble in water but should not be used in acidic or strong alkaline so ...
... The material which is most commonly used for ATR spectroscopy is ZnSe. ZnSe has a refractive index of 2.4 making it suitable for most organic materials and it has a transmission range from 20,000 to 650 cm-1 . This material is insoluble in water but should not be used in acidic or strong alkaline so ...
Ab initio modelling tutorial (part II)
... grouping – Normalized spatial deviation serves as a distance between heterogeneous models (e.g. bead models) – R.m.s.d. is employed for those with atom-to-atom correspondence (e.g. rigid body models) ...
... grouping – Normalized spatial deviation serves as a distance between heterogeneous models (e.g. bead models) – R.m.s.d. is employed for those with atom-to-atom correspondence (e.g. rigid body models) ...
a-study-on-the
... that the dimension of the ZSG increased by doping. Powder XRD analysis revealed the crystalline nature of the grown crystals. Single crystal XRD revealed that the ZSG had acquired the structure of α glycine and it existed in zwitter ionic form, which resulted in the modifications of the properties. ...
... that the dimension of the ZSG increased by doping. Powder XRD analysis revealed the crystalline nature of the grown crystals. Single crystal XRD revealed that the ZSG had acquired the structure of α glycine and it existed in zwitter ionic form, which resulted in the modifications of the properties. ...
Wulff construction and grain boundary in HCP crystals
... cut and connected to the other crystal in different orientations. This connecting interface is called the Grain boundary. For describing effectively this connection, let us use a notation including the first crystal's axis system, the axis of the interface, and their relative orientation using the r ...
... cut and connected to the other crystal in different orientations. This connecting interface is called the Grain boundary. For describing effectively this connection, let us use a notation including the first crystal's axis system, the axis of the interface, and their relative orientation using the r ...
Perspective for Journal of Pharmaceutical Science
... consistent with a product (26). Therefore, the discovery of the salt form ensured both shelf stability and robust bioavailability performance. The salt selection strategy is limited in two ways. First, salt formation relies on the presence of one or more ionizable functional groups in the molecule; ...
... consistent with a product (26). Therefore, the discovery of the salt form ensured both shelf stability and robust bioavailability performance. The salt selection strategy is limited in two ways. First, salt formation relies on the presence of one or more ionizable functional groups in the molecule; ...
gamma radiation effects on electro
... the duration was 20 minutes. During this we recorded the changes of Hall’s Constanta, which is shown in the diagram of fig.2. Experimental measurements show that after the action with gamma rays and upon heating to higher temperatures appears an instability of the defects set by radiation. Tests, do ...
... the duration was 20 minutes. During this we recorded the changes of Hall’s Constanta, which is shown in the diagram of fig.2. Experimental measurements show that after the action with gamma rays and upon heating to higher temperatures appears an instability of the defects set by radiation. Tests, do ...
Minerals
... Crystals Not all mineral crystals have smooth surfaces and regular shapes like the clear quartz crystals in Figure 2. The rose quartz in the smaller photo of Figure 2 has atoms arranged in repeating patterns, but you can’t see the crystal shape on the outside of the mineral. This is because the rose ...
... Crystals Not all mineral crystals have smooth surfaces and regular shapes like the clear quartz crystals in Figure 2. The rose quartz in the smaller photo of Figure 2 has atoms arranged in repeating patterns, but you can’t see the crystal shape on the outside of the mineral. This is because the rose ...
IDENTIFICATION OF PHYSICAL INTERACTION BETWEEN ANTI MALARIAL DRUGS COMBINATION ARTESUNATE-AMODIAQUINE HYDROCHLORIDE
... between AS and AQ was analysed by powder X-ray diffraction, FTIR spectrophotometric, microscopic SEM and thermal DTA, TG-DSC. Microscopic analysis by SEM shown significantly the change of habit and morphology of crystal as long and thin needle shaped. The difference of powder X-ray diffraction (PXRD ...
... between AS and AQ was analysed by powder X-ray diffraction, FTIR spectrophotometric, microscopic SEM and thermal DTA, TG-DSC. Microscopic analysis by SEM shown significantly the change of habit and morphology of crystal as long and thin needle shaped. The difference of powder X-ray diffraction (PXRD ...
www.ualberta.ca - University of Alberta
... salt ethanol solvate (24,25) The crystalline free base has variable oral bioavailability in dogs (26,27) and humans (28). While acidic solutions of the base compound showed good oral pharmacokinetics, the stability of the drug in acidic solution is not consistent with a product (26). Therefore, the ...
... salt ethanol solvate (24,25) The crystalline free base has variable oral bioavailability in dogs (26,27) and humans (28). While acidic solutions of the base compound showed good oral pharmacokinetics, the stability of the drug in acidic solution is not consistent with a product (26). Therefore, the ...
Irregular organization in the human chromosomes - SPring-8
... the hierarchical helical folding model (Fig. 1(b)). The cryo-EM, SAXS, and USAXS data collectively indicate that the irregularly folded nucleosome fibers make up the bulk structure of human mitotic chromosomes. How is the nucleosome fiber organized into a mitotic chromosome? Since condensin and topo ...
... the hierarchical helical folding model (Fig. 1(b)). The cryo-EM, SAXS, and USAXS data collectively indicate that the irregularly folded nucleosome fibers make up the bulk structure of human mitotic chromosomes. How is the nucleosome fiber organized into a mitotic chromosome? Since condensin and topo ...
Crystallographic studies of two bacterial antibiotic resistance enzymes
... classes: A, B, C, and D [4]. The GES family is a class A -lactamase, and is further classified as a third generation carbapenemase. The general structure of carbapenems is shown in Figure 1. The protein of interest in this study, GES-1, shows strong activity against most carbapenems, with some exc ...
... classes: A, B, C, and D [4]. The GES family is a class A -lactamase, and is further classified as a third generation carbapenemase. The general structure of carbapenems is shown in Figure 1. The protein of interest in this study, GES-1, shows strong activity against most carbapenems, with some exc ...
Enhanced pyroelectric crystal D—D nuclear fusion
... During cooling, the electric field generated between the pyroelectric crystals is high enough to ionize D2 gas. The ratio of D2 + to D+ ionization is not clear. For the results reported by Tang et al. [3] at LLNL, neutron yield calculations indicated that the ion beam was predominantly D+ and not D2 ...
... During cooling, the electric field generated between the pyroelectric crystals is high enough to ionize D2 gas. The ratio of D2 + to D+ ionization is not clear. For the results reported by Tang et al. [3] at LLNL, neutron yield calculations indicated that the ion beam was predominantly D+ and not D2 ...
Crystal Buffers
... precision. There is no need to spend time in the laboratory weighing and handling the individual components for preparing buffers. Simply dissolve the contents of the pouch or place the tablet in deionized water to the recommended volume and you are ready to go without any further preparation. ...
... precision. There is no need to spend time in the laboratory weighing and handling the individual components for preparing buffers. Simply dissolve the contents of the pouch or place the tablet in deionized water to the recommended volume and you are ready to go without any further preparation. ...
Three-dimensional photonic crystals for optical wavelengths
... joined. However, when we took the fluctuation of the photonic pattern which was caused by dry etching into account, the positioning error was found to be within 50 nm. The optical properties of crystals were evaluated using a Fourier-transform infrared measurement system for wavelengths from 1.4 to ...
... joined. However, when we took the fluctuation of the photonic pattern which was caused by dry etching into account, the positioning error was found to be within 50 nm. The optical properties of crystals were evaluated using a Fourier-transform infrared measurement system for wavelengths from 1.4 to ...
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.