Log in

Relevant bibliographies by topics / Hexagonal Close Packing / Journal articles

To see the other types of publications on this topic, follow the link: Hexagonal Close Packing.

Journal articles on the topic 'Hexagonal Close Packing'

Author: Grafiati

Published: 4 June 2021

Last updated: 2 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Hexagonal Close Packing.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

BURSILL, L. A., and FAN XUDONG. "CLOSE-PACKING OF GROWING DISCS." Modern Physics Letters B 02, no. 11n12 (1988): 1245–52. http://dx.doi.org/10.1142/s0217984988001193.

Full text

Abstract:

Spiral lattices are derived by allowing growing discs to aggregate under a close-packing rule. Both Fibonacci and Lucas numbers of visible spirals arise naturally, dependent only on the choice of growth centre. Both the rate of convergence towards an ideal spiral, and chirality, are determined by the initial placement of the first few discs (initial conditions). Thus the appearance of spiral packings is no more or less mysterious than the appearance of hexagonal packed arrays of equal discs.

APA, Harvard, Vancouver, ISO, and other styles

2

Almarza, N. G. "Hexagonal close-packing structure on a cubic cell." Journal of Chemical Physics 123, no. 5 (2005): 056101. http://dx.doi.org/10.1063/1.1997138.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Emmerling, Franziska, and Caroline Röhr. "Alkalimetall-Arsenide A3As7 Und Aas (A = K, Rb, Cs). Synthesen, Kristallstrukturen, Schwingungsspektren / Alkaline Metal Arsenides A3As7 and AAs (A = K, Rb, Cs). Preparation, Crystal Structure, Vibrational Spectroscopy." Zeitschrift für Naturforschung B 57, no. 9 (2002): 963–75. http://dx.doi.org/10.1515/znb-2002-0901.

Full text

Abstract:

The title compounds were synthesized from the elements and characterized via single crystal x-ray studies and Raman spectroscopy. In the Zintl phases A3As7 (A = K, Rb, Cs) the As atoms form nortricyclene-analogous anions As37 with As-As distances ranging from 230 to 254 pm. The three compounds crystallizewithdifferent newstructure types containing different packings of theAs7 anions:K3As7 (orthorhombic, Pbca; a=1291.9(8), b = 2544.1(9), c=1537.7(16) pm) shows a double hexagonal close packing (ABAC stacking of planes of hexagonal close packed anions), Rb3 As7 (monoclinic, P21/c, a = 757.3(5), b

APA, Harvard, Vancouver, ISO, and other styles

4

Zeng, Xiangbing, Yongsong Liu, and Marianne Impéror-Clerc. "Hexagonal Close Packing of Nonionic Surfactant Micelles in Water." Journal of Physical Chemistry B 111, no. 19 (2007): 5174–79. http://dx.doi.org/10.1021/jp0687955.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Wolff, Nicole, Stefan Gerth, Philipp Gutfreund, and Max Wolff. "Temperature dependent cubic and hexagonal close packing in micellar structures." Soft Matter 10, no. 42 (2014): 8420–26. http://dx.doi.org/10.1039/c4sm01569j.

Full text

Abstract:

The delicate correlation of temperature, micellar properties and type of structure is investigated for a micellar crystal at a solid boundary. The cubic and hexagonal close packing is analyzed in detail by grazing incidence neutron scattering.

APA, Harvard, Vancouver, ISO, and other styles

6

Wahab, Mohammad Abdul, and Khurram Mujtaba Wahab. "Study That Led to the Discovery of Rhombohedral Close Packing and Hexagonal Close Packing as Two New and Independent Lattices." Advanced Science, Engineering and Medicine 11, no. 12 (2019): 1179–86. http://dx.doi.org/10.1166/asem.2019.2465.

Full text

Abstract:

An ab-initio calculation of angles has been made between various directions on close packed basal plane with the tilted axis obtained by placing identical atoms on voids. Results obtained from simple calculations provide a lot of important information related to Rhombohedral Close Packed and Hexagonal Close Packed structures, effectively leading to their discovery as independent and genuine space lattices from close packed category of materials. En-route, we also propose a separate equation to calculate the angles between two given directions in the above mentioned close packed crystal systems

APA, Harvard, Vancouver, ISO, and other styles

7

de Lara-Castells, María Pilar, Andreas W. Hauser, Alexander O. Mitrushchenkov, and Ricardo Fernández-Perea. "Quantum confinement of molecular deuterium clusters in carbon nanotubes: ab initio evidence for hexagonal close packing." Physical Chemistry Chemical Physics 19, no. 42 (2017): 28621–29. http://dx.doi.org/10.1039/c7cp05869a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Nowak, Roberta B., Robert S. Fischer, Rebecca K. Zoltoski, Jerome R. Kuszak, and Velia M. Fowler. "Tropomodulin1 is required for membrane skeleton organization and hexagonal geometry of fiber cells in the mouse lens." Journal of Cell Biology 186, no. 6 (2009): 915–28. http://dx.doi.org/10.1083/jcb.200905065.

Full text

Abstract:

Hexagonal packing geometry is a hallmark of close-packed epithelial cells in metazoans. Here, we used fiber cells of the vertebrate eye lens as a model system to determine how the membrane skeleton controls hexagonal packing of post-mitotic cells. The membrane skeleton consists of spectrin tetramers linked to actin filaments (F-actin), which are capped by tropomodulin1 (Tmod1) and stabilized by tropomyosin (TM). In mouse lenses lacking Tmod1, initial fiber cell morphogenesis is normal, but fiber cell hexagonal shapes and packing geometry are not maintained as fiber cells mature. Absence of Tmo

APA, Harvard, Vancouver, ISO, and other styles

9

Lucadamo, G. "Geometric Origin of Hexagonal Close Packing at a Grain Boundary in Gold." Science 300, no. 5623 (2003): 1272–75. http://dx.doi.org/10.1126/science.1083890.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Beck, J., and F. Wolf. "Three New Polymorphic Forms of Molybdenum Pentachloride." Acta Crystallographica Section B Structural Science 53, no. 6 (1997): 895–903. http://dx.doi.org/10.1107/s0108768197008331.

Full text

Abstract:

Three new polymorphic modifications of molybdenum pentachloride could be obtained by solvothermal syntheses in CCl4 and SbCl5 as solvents. The structures have been solved by single-crystal X-ray diffraction. The already known structure of monoclinic \alpha-MoCl5 (C2/m) is not isomorphous with \alpha-NbCl5 and is better derived from the closest packing of Cl atoms of the Sm type with molybdenum occupying 1/5 of the octahedral holes. The triclinic structure of \beta-MoCl5 (P\overline 1) can be derived from hexagonal closest packing. The orthorhombic structure of \gamma-MoCl5 (Pnma) and the monoc

APA, Harvard, Vancouver, ISO, and other styles

11

Pakhomova, Anna, Elena Bykova, Maxim Bykov, et al. "A closer look into close packing: pentacoordinated silicon in a high-pressure polymorph of danburite." IUCrJ 4, no. 5 (2017): 671–77. http://dx.doi.org/10.1107/s2052252517010612.

Full text

Abstract:

Due to their high technological and geological relevance, silicates are one of the most studied classes of inorganic compounds. Under ambient conditions, the silicon in silicates is almost exclusively coordinated by four oxygen atoms, while high-pressure treatment normally results in an increase in the coordination from four- to sixfold. Reported here is a high-pressure single-crystal X-ray diffraction study of danburite, CaB2Si2O8, the first compound showing a step-wise transition of Si coordination from tetrahedral to octahedral through a trigonal bipyramid. Along the compression, the Si2O7g

APA, Harvard, Vancouver, ISO, and other styles

12

Amayuelas, Eder, Arkaitz Fidalgo-Marijuan, Gotzone Barandika, Begoña Bazán, Miren-Karmele Urtiaga, and María Isabel Arriortua. "Mother structures related to the hexagonal and cubic close packing in Cu24 clusters: solvent-influenced derivatives." CrystEngComm 17, no. 17 (2015): 3297–304. http://dx.doi.org/10.1039/c5ce00251f.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Wahab, M. A., and Khurram Mujtaba Wahab. "Genesis of Hexagonal Close Packed (HCP) Structures from Packing of Identical Spheres (Atoms)." Materials Focus 7, no. 2 (2018): 223–31. http://dx.doi.org/10.1166/mat.2018.1503.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Harfenist, S. A., Z. L. Wang, R. L. Whetten, I. Vezmar, M. M. Alvarez, and B. E. Salisbury. "Three-Dimensional Hexagonal Close-Packed Superlattices of Passivated Ag Nanocrystals." Microscopy and Microanalysis 3, S2 (1997): 431–32. http://dx.doi.org/10.1017/s1431927600009041.

Full text

Abstract:

Silver nanocrystals passivated by dodecanethiol self-assembled monolayers were produced using an aerosol technique described in detail elsewhere [1]. Self-assembling passivated nanocrystal-superlattices (NCS's) involve self-organization into monolayers, thin films, and superlattices of size-selected nanoclusters encapsulated in a protective compact coating [2,3,4,5,6,7]. We report the preparation and structure characterization of three-dimensional (3-D) hexagonal close-packed Ag nanocrystal supercrystals from Ag nanocrystals of ˜4.5 nm in diameters. The crystallography of the superlattice and

APA, Harvard, Vancouver, ISO, and other styles

15

Impéror-Clerc, Marianne. "Three-dimensional periodic complex structures in soft matter: investigation using scattering methods." Interface Focus 2, no. 5 (2012): 589–601. http://dx.doi.org/10.1098/rsfs.2011.0081.

Full text

Abstract:

Three-dimensional periodic complex structures are encountered in various soft matter systems such as liquid crystals, block-copolymer phases and the related nano-structured materials. Here, we review several well-defined topologies: two-dimensional hexagonal phase, three-dimensional packing of spheres, tetrahedral close packing ( tcp ) bi-continuous and tri-continuous cubic phases. We illustrate how small-angle X-ray scattering experiments help us to investigate these different structures and introduce the main available structural models based on both direct and inverse methods.

APA, Harvard, Vancouver, ISO, and other styles

16

Pavlyuk, Volodymyr, Ihor Chumak, Lev Akselrud, Sven Lidin, and Helmut Ehrenberg. "LiZn4 − x(x= 0.825) as a (3 + 1)-dimensional modulated derivative of hexagonal close packing." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 70, no. 2 (2014): 212–17. http://dx.doi.org/10.1107/s2052520613030709.

Full text

Abstract:

The (3+1)-dimensional modulated structure of the LiZn4 − x(x= 0.825) binary compound has been determined in the superspace. The compound crystallizes in the orthorhombic superspace groupCmcm(α00)0s0 witha= 2.7680 (6),b= 4.7942 (6),c= 4.3864 (9) Å, modulation wavevector:q≃ 4/7a*. The structure is a derivative from the hexagonal close packing. The cubo-octahedron as a coordination polyhedron (c.n. = 12) is typical for all atoms. Bonding between atoms is explored by means of theTB-LMTO-ASAprogram package. The absence of strong interatomic interactions in LiZn4 − xis the main reason for the possib

APA, Harvard, Vancouver, ISO, and other styles

17

Kim, Yongbeom, Gyungmin Hwang, and Joonhyeon Jeon. "A volume-porous conductive electrode by hexagonal close packing of phenolic resin-based carbon spheres." Materials Letters 254 (November 2019): 301–4. http://dx.doi.org/10.1016/j.matlet.2019.07.079.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Neuhausen, Jörg, Karl-Ludwig Stork, Elisabeth Potthoff, and Wolfgang Tremel. "Synthese und Struktur von Nb0,89Fe0,93Te2 und Ta0,77Fe0,90Te2 / Synthesis and Structure of Nb0.89Fe0.93Te2 and Ta0.77Fe0.90Te2." Zeitschrift für Naturforschung B 47, no. 9 (1992): 1203–12. http://dx.doi.org/10.1515/znb-1992-0901.

Full text

Abstract:

Nb0.89Fe0.93Te2 and Ta0.77Fe0.90Te2 were prepared by chemical transport reactions. The crystal structures of both compounds were determined using X-ray single crystal methods. The structures of the layer compounds Nb0.89Fe0.93Te2 (Pmna, Z = 2, a = 7.951(1) Å, b = 7.241(1) A, c = 6.233(1) Å) and Ta0.77Fe0.90Te2 (Pmna, Z = 2, a = 7.890(2) Å, b = 7.252(2) Å, c = 6.192(1) Å) are based on a hexagonal close packing of Te atoms. Approximately one-half of the octahedral holes in this packing are occupied by Nb (Ta) atoms, about one-quarter of the tetrahedral holes are occupied by Fe atoms. The relatio

APA, Harvard, Vancouver, ISO, and other styles

19

Raransky, M. D., Ch R. Tretiak, M. M. Gunko, and V. N. Balazyuk. "The Impact of d– and f–compression on Anisotropy of Elastic Properties of Single Crystals with Hexagonal Close Packing of Lattice." Фізика і хімія твердого тіла 17, no. 2 (2016): 170–79. http://dx.doi.org/10.15330/pcss.17.2.170-179.

Full text

Abstract:

Characteristic surfaces of Young's moduli were created usingtheory of elasticity of anisotropic crystals and computer processing of experimental data and patterns of their formationwere established. Detailed analysis of anisotropy of elastic properties of single crystals of transition metals with hexagonal close packing of lattice were conducted. Theimpact of d– and f–compression on anisotropy of elastic properties was discovered for the first time. A correlation between the anisotropy of elasticity and other physical properties of transition metals was established.

APA, Harvard, Vancouver, ISO, and other styles

20

Hou, Jinghui, Yifei Ma, Zihan Zhang, Xuanhe Yang, Muhua Huang, and Chunpeng Chai. "The Relationship between Solid Content and Particle Size Ratio of Waterborne Polyurethane." Coatings 9, no. 6 (2019): 401. http://dx.doi.org/10.3390/coatings9060401.

Full text

Abstract:

A series of high solid content carboxylic acid/sulfonic acid waterborne polyurethanes was prepared by the emulsion dispersion method. The particle size and solid content were measured. By changing the particle size of the large particles to achieve different particle size ratios, high solid content waterborne polyurethanes were obtained at specific particle size ratios. When the particle size ratio was >7, 4–5 or 2–3, the aqueous polyurethane could reach a higher solid content (more than 56%). This indicated that solid content is related to particle size distribution in high solid content w

APA, Harvard, Vancouver, ISO, and other styles

21

Jones, Kenneth A. "Structural Analysis of Off-Axis SiC Planes for the Growth of SiC and AlGaN Films." Materials Science Forum 600-603 (September 2008): 369–72. http://dx.doi.org/10.4028/www.scientific.net/msf.600-603.369.

Full text

Abstract:

An orientation relationship between the cubic 3C and nH hexagonal structures was developed to identify low surface energy, close packed, conducive to growth hexagonal semi-polar planes. This was done to identify planes on which micropipe free SiC crystals, and/or hetero-epitaxial AlGaN structures with a reduced piezoelectric field and a smaller lattice mismatch could be grown. The nH (33 0 2n)H and (33 0 n )H hexagonal planes, which correspond to the (100)C and (111)C cubic planes are identified, and equations are developed to determine their planar structure and packing density to assess whet

APA, Harvard, Vancouver, ISO, and other styles

22

Albrecht, Ralf, Heinrich Menning, Thomas Doert, and Michael Ruck. "Hydroflux synthesis and crystal structure of Tl3IO." Acta Crystallographica Section E Crystallographic Communications 76, no. 10 (2020): 1638–40. http://dx.doi.org/10.1107/s2056989020012359.

Full text

Abstract:

Single-crystals of thallium(I) iodide oxide Tl3IO were obtained as by-product in a hydroflux synthesis at 473 K for 10 h. A potassium hydroxide hydroflux with a water-base molar ratio of 1.6 and the starting materials TlNO3, RhI3 and Ba(NO3)2 was used, resulting in a few black needle-shaped crystals. X-ray diffraction on a single-crystal revealed the hexagonal space group P63/mmc (No. 194) with lattice parameters a = 7.1512 (3) Å and c = 6.3639 (3) Å. Tl3IO crystallizes as hexagonal anti-perovskite (anti-BaNiO3 type) and is thus structurally related to the alkali-metal halide/auride oxides M 3

APA, Harvard, Vancouver, ISO, and other styles

23

Thomas, Noel W. "A novel characterization of organic molecular crystal structures for the purpose of crystal engineering." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 71, no. 4 (2015): 463–77. http://dx.doi.org/10.1107/s2052520615011312.

Full text

Abstract:

A novel analytical approach is proposed for the characterization of organic molecular crystal structures where close packing is an important factor. It requires the identification of a unique reference axis within the crystal, along which three-dimensional space is divided into close-packed blocks (CPB) and junction zones (JZ). The degree of close packing along the reference axis is quantified by a two-dimensional packing function, φ2D, of symmetry determined by the space group. Values of φ2Dreflect the degree of area-filling in planes perpendicular to this axis. The requirement of close packi

APA, Harvard, Vancouver, ISO, and other styles

24

Chacón, C., P. Delgado-Niño, and G. E. Delgado. "Synthesis and crystal structure determination of the new olivine-type compound Mn2SnSe4." Revista Mexicana de Física 66, no. 1 (2019): 30. http://dx.doi.org/10.31349/revmexfis.66.30.

Full text

Abstract:

The Mn2SnSe4 compound was synthesized by the melt and annealing technique and its structure was refined by the Rietveld method using X-ray powder diffraction data. This compound crystallizes in the olivine-type structure with unit cell parameters a = 12.9028(2) Å, b = 7.9001(1) Å, c = 6.5015(1) Å, V = 662.72(2) Å3 in the orthorhombic space group Pnma (Nº 62). This olivine structure can be described from a hexagonal close-packing of selenium atoms where manganese atoms occupy ½ of the octahedral sites while thin atoms lay in ⅛ of the tetrahedra.

APA, Harvard, Vancouver, ISO, and other styles

25

Longo, Alessandro, Luisa Sciortino, Francesco Giannici, and Antonino Martorana. "Crossing the boundary between face-centred cubic and hexagonal close packed: the structure of nanosized cobalt is unraveled by a model accounting for shape, size distribution and stacking faults, allowing simulation of XRD, XANES and EXAFS." Journal of Applied Crystallography 47, no. 5 (2014): 1562–68. http://dx.doi.org/10.1107/s1600576714015970.

Full text

Abstract:

The properties of nanostructured cobalt in the fields of magnetic, catalytic and biomaterials depend critically on Co close packing. This paper reports a structural analysis of nanosized cobalt based on the whole X-ray diffraction (XRD) pattern simulation allowed by the Debye equation. The underlying structural model involves statistical sequences of cobalt layers and produces simulated XRD powder patterns bearing the concurrent signatures of hexagonal and cubic close packing (h.c.p. and f.c.c.). Shape, size distribution and distance distribution between pairs of atoms are also modelled. The s

APA, Harvard, Vancouver, ISO, and other styles

26

Aceñolaza, Guillermo F., M. Franco Tortello, and Isabel Rábano. "The eyes of the early Tremadoc olenid trilobite Jujuyaspis keideli Kobayashi, 1936." Journal of Paleontology 75, no. 2 (2001): 346–50. http://dx.doi.org/10.1017/s002233600001814x.

Full text

Abstract:

The morphology of the eyes of the olenid trilobite Jujuyaspis keideli Kobayashi, 1936, is described and illustrated. Studied specimens come from Early Tremadocian pyritiferous black shales of the Casa Colorada Formation (= Purmamarca shales) at Purmamarca, Jujuy Province, northwestern Argentina. The eyes are holochroal and proportionately large relative to the overall size of cephalon. They are always found attached to the librigena, showing no preserved lenses, only molds of their surfaces. Their molds demonstrate that lenses were numerous, biconvex, hexagonal in outline and arranged in an he

APA, Harvard, Vancouver, ISO, and other styles

27

Ullas, A. V., Devendra Kumar, and Prasun Kumar Roy. "Epoxy-Glass Microballoon Syntactic Foams: Rheological Optimization of the Processing Window." Advances in Polymer Technology 2019 (April 1, 2019): 1–12. http://dx.doi.org/10.1155/2019/9180302.

Full text

Abstract:

In this paper, we discuss the chemorheology of epoxy based syntactic foams containing glass microballoons of varying density, with an aim of establishing the effect of microballoon loading on its processability. The primary objective is to determine the maximum microballoon loading that disperses uniformly in the resin without the aid of any diluent. The viscosity and dynamic mechanical properties of epoxy formulations containing varying amounts of glass microballoons were established by parallel plate rheometry. Our studies reveal that solventless processing of formulations with microballoon

APA, Harvard, Vancouver, ISO, and other styles

28

van de Waal, Benjamin W. "Static relaxation of bcc crystal fragments using a Lennard–Jones potential: Transition to hexagonal or cubic close packing." Journal of Crystal Growth 309, no. 2 (2007): 181–91. http://dx.doi.org/10.1016/j.jcrysgro.2007.09.012.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Reichwein, Lars, Johannes Thomas, and Alexander Pukhov. "The filamented electron bunch of the bubble regime." Laser and Particle Beams 38, no. 2 (2020): 121–27. http://dx.doi.org/10.1017/s0263034620000130.

Full text

Abstract:

AbstractWe present a theory for describing the inner structure of the electron bunch in the bubble regime starting from a random distribution of electrons inside the bubble and subsequently minimizing the system's energy. Consequently, we find a filament-like structure in the direction of propagation that is surrounded by various shells consisting of further electrons. If we specify a two-dimensional (2D) initial structure, we observe a hexagonal structure for a high number of particles, corresponding to the close packing of spheres in two dimensions. The 2D structures are in agreement with th

APA, Harvard, Vancouver, ISO, and other styles

30

Garau, Gianpiero, Silvano Geremia, Luigi G. Marzilli, Giorgio Nardin, Lucio Randaccio, and Giovanni Tauzher. "Crystal chemistry and binding of NO2, SCN and SeCN to Co in cobalamins." Acta Crystallographica Section B Structural Science 59, no. 1 (2003): 51–59. http://dx.doi.org/10.1107/s0108768102019353.

Full text

Abstract:

Results of the accurate crystal structure determination of NO2Cbl·2LiCl (1), NO2Cbl·NaCl (2), NCSCbl (3) and NCSeCbl (4), based on synchrotron diffraction data collected at 100 K, are described. The nitro group in (1) was found to be disordered with two orientations that differ by a rotation of ∼60° about the Co—NO2 bond, whereas in (2) the nitro group has only one orientation. The first X-ray structural determination of a cobalamin with a Co—Se bond is reported. Comparison of the axial distances indicates that SeCN has a bond length of 2.384 (3) Å and that the trans influence on the Co—N bond

APA, Harvard, Vancouver, ISO, and other styles

31

Zhang, Ying, Bolong Huang, Gan Luo, et al. "Atomically deviated Pd-Te nanoplates boost methanol-tolerant fuel cells." Science Advances 6, no. 31 (2020): eaba9731. http://dx.doi.org/10.1126/sciadv.aba9731.

Full text

Abstract:

The methanol crossover effect in direct methanol fuel cells (DMFCs) can severely reduce cathodic oxygen reduction reaction (ORR) performance and fuel efficiency. As a result, developing efficient catalysts with simultaneously high ORR activity and excellent antipoisoning methanol capability remains challenging. Here, we report a class of Pd-Te hexagonal nanoplates (HPs) with a Pd20Te7 phase that simultaneously overcome the activity and methanol-tolerant issues in alkaline DMFC. Because of the specific arrangement of Pd atoms deviated from typical hexagonal close-packing, Pd-Te HPs/C displays e

APA, Harvard, Vancouver, ISO, and other styles

32

Weil, Matthias. "Redetermination of Ag2[TeO2(OH)4]: a revised hydrogen-bonding scheme." Acta Crystallographica Section E Structure Reports Online 63, no. 3 (2007): i77—i79. http://dx.doi.org/10.1107/s1600536807007970.

Full text

Abstract:

The crystal structure of the title compound, disilver(I) tetrahydrododioxotellurate(VI), has been redetermined; it confirms the previous study [Fischer (1969). Monatsh. Chem. 100, 1809–1822] which was based on film data, but with higher precision, with all displacement factors refined anisotropically for non-H atoms and with the localization of the H atoms, which leads to a different hydrogen-bonding scheme from that originally proposed. The structure of Ag2[TeO2(OH)4] can be derived from a distorted hexagonal close packing of [TeO2(OH)4]2− octahedra (Te site symmetry 2) with the Ag+ cations l

APA, Harvard, Vancouver, ISO, and other styles

33

Zhang, Bao, Idris K. Mohammed, Yi Wang, and Daniel S. Balint. "On the use of HCP and FCC RVE structures in the simulation of powder compaction." Journal of Strain Analysis for Engineering Design 53, no. 5 (2018): 338–52. http://dx.doi.org/10.1177/0309324718774188.

Full text

Abstract:

Use of hexagonal close packed and face centered cubic structures to simulate powder compaction reveals that plastic deformation is effective in reducing porosity until a relative density of 0.96, beyond which a drastic rise in pressure is required. The compaction process can be divided into three phases demarcated by relative densities of 0.8 and 0.92, characterized, respectively, by local yielding around the initial contact point, coalescence of locally yielded zones and full plastic flow to reduce pores. The macroscopic yield behaviour of the powder assembly in the present work agrees reason

APA, Harvard, Vancouver, ISO, and other styles

34

Ishikawa, Toshihiro. "SA-Tyrannohex-Based Composite for High Temperature Applications." Advances in Science and Technology 71 (October 2010): 118–26. http://dx.doi.org/10.4028/www.scientific.net/ast.71.118.

Full text

Abstract:

To modify the relatively low fracture toughness of monolithic ceramics, the incorporation of long ceramic fibre within a matrix material has been extensively performed. In this case, as cracks form in the matrix material and approach the fibres, they will be deflected at the interface between the fibre and the matrix. We developed another approach toward improving the toughness of ceramics involving the creation of a textured internal structure within the ceramic itself, similar in some respects to the fibrous structure of wood. Actually, we developed a tough ceramic, which consists of a highl

APA, Harvard, Vancouver, ISO, and other styles

35

Drits, V. A., B. A. Sakharov, A. L. Salyn, and A. Manceau. "Structural Model for Ferrihydrite." Clay Minerals 28, no. 2 (1993): 185–207. http://dx.doi.org/10.1180/claymin.1993.028.2.02.

Full text

Abstract:

AbstractThe structure of 6-line and 2-line ferrihydrite (Fh) has been reconsidered. X-ray diffraction (XRD) curves were first simulated for the different structural models so far proposed, and it is shown that neither of these corresponds to the actual structure of ferrihydrite. On the basis of agreement between experimental and simulated XRD curves it is shown that Fh is a mixture of three components: (i) Defect-free Fh consisting of anionic ABACA . . . close packing in which Fe atoms occupy only octahedral sites with 50% probability; the hexagonal unit-cell parameters are a = 2-96 Å and c =

APA, Harvard, Vancouver, ISO, and other styles

36

Yang, Chao-Chen, and Min-Fong Shu. "Electrodeposition of Zinc from Binary ZnCl2-DMSO2 Molten Electrolyte at Room Temperature." Zeitschrift für Naturforschung A 62, no. 12 (2007): 754–60. http://dx.doi.org/10.1515/zna-2007-1214.

Full text

Abstract:

The electrochemical behaviour of zinc on copper, platinum, and tungsten working electrodes was investigated in a binary ZnCl2-DMSO2 room temperature molten salt electrolyte in the temperature range of 60 - 80◦C. Various over-potentials, −0.1, −0.2, −0.3, −0.4, and −0.5 V, were chosen as deposition potentials. The nucleation/growth of zinc changed from progressive to instantaneous if the over-potentials increased from low to high level. The surface morphology and crystal structure of the deposited layer were investigated using scanning electron microscopy (SEM) and X-ray diffraction (XRD). More

APA, Harvard, Vancouver, ISO, and other styles

37

Černý, Radovan, Matteo Brighi, and Fabrizio Murgia. "The Crystal Chemistry of Inorganic Hydroborates." Chemistry 2, no. 4 (2020): 805–26. http://dx.doi.org/10.3390/chemistry2040053.

Full text

Abstract:

The crystal structures of inorganic hydroborates (salts and coordination compounds with anions containing hydrogen bonded to boron) except for the simplest anion, borohydride BH4−, are analyzed regarding their structural prototypes found in the inorganic databases such as Pearson’s Crystal Data [Villars and Cenzual (2015), Pearson’s Crystal Data. Crystal Structure Database for Inorganic Compounds, Release 2019/2020, ASM International, Materials Park, Ohio, USA]. Only the compounds with hydroborate as the only type of anion are reviewed, although including compounds gathering more than one diff

APA, Harvard, Vancouver, ISO, and other styles

38

Pertlik, Franz. "The Distortion of the Hexagonal Close Packing of Oxygen Atoms in Co(OH)2 Compared to Isotypic Brucite-Type Structures." Monatshefte für Chemie / Chemical Monthly 130, no. 9 (1999): 1083–88. http://dx.doi.org/10.1007/pl00010286.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Li, Z. G., and Paul J. Fagan. "Observations of coexistence of FCC and HCP phases in C60 by HREM." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 1 (1992): 110–11. http://dx.doi.org/10.1017/s0424820100120953.

Full text

Abstract:

Since the discovery of a large scale synthesis of fullerenes there has been intense interest in the structure of these materials. The first diffraction data suggested that crystalline C60 had a hexagonal close-packed (hep) structure with a nearest neighbor distance of 10.04 Å. The possibility of a disordered stacking of C60 molecules was first noted in this study. Since then, there has been some confusion regarding the exact crystalline structure of C60 as determined by electron and X-ray diffraction. In particular, a diffraction feature corresponding to a spacing of 8.7 Å has been noted in se

APA, Harvard, Vancouver, ISO, and other styles

40

Dusek, Michal, Gervais Chapuis, Penelope Schobinger-Papamantellos, et al. "Modulated structure of La2Co1.7 from neutron and X-ray diffraction data." Acta Crystallographica Section B Structural Science 56, no. 6 (2000): 959–71. http://dx.doi.org/10.1107/s0108768100011332.

Full text

Abstract:

An La2Co1.7 crystal was investigated by single-crystal neutron and X-ray diffraction. The neutron measurement was performed with a Laue white-beam technique at 15 K and room temperature, using a large position-sensitive detector. The X-ray measurements were obtained at room temperature from a CCD detector. The average structure of La2Co1.7 is hexagonal with cell parameters a = 4.885 (1), c = 4.273 (2) Å and space group P63/mmc. The satellites are located at the vertices of small hexagons perpendicular to the c axis. The modulated crystal was indexed assuming a sixfold twinned 3 + 1 dimensional

APA, Harvard, Vancouver, ISO, and other styles

41

Carlson, Stefan, Ann-Kristin Larsson, and Franziska E. Rohrer. "High-pressure transformations of NbO2F." Acta Crystallographica Section B Structural Science 56, no. 2 (2000): 189–96. http://dx.doi.org/10.1107/s0108768199015311.

Full text

Abstract:

The ReO3-type structure NbO2F, niobium dioxyfluoride, has been studied at high pressures using diamond anvil cells and synchrotron X-ray radiation. High-pressure powder diffraction measurements have been performed up to 40.1 GPa. A phase transition from the cubic (Pm3¯m) ambient pressure structure to a rhombohedral (R3¯c) structure at 0.47 GPa has been observed. Rietveld refinements at 1.38, 1.96, 3.20, 6.23, 9.00 and 10.5 GPa showed that the transition involves an a − a − a − tilting of the cation–anion coordination octahedra and a change of the anion–anion arrangement to approach hexagonal c

APA, Harvard, Vancouver, ISO, and other styles

42

GOYAL, M., and B. R. K. GUPTA. "Analysis of shape, size and structure dependent thermodynamic properties of nanowires." High Temperatures-High Pressures 48, no. 5-6 (2020): 481–95. http://dx.doi.org/10.32908/hthp.v48.733.

Full text

Abstract:

A simple model based on thermodynamic variables is used to study the effect of shape, size and structure on the various thermodynamic properties of nanowires. The expression of cohesive energy derived by Qi and Wang [16] is used and ratio of surface atoms to total number of atoms is expressed in terms of shape parameter, radius of nanowire and atomic packing fraction. The variation in cohesive energy, activation energy, melting temperature surface energy, Bulk modulus, Energy band gap Debye temperature and coefficient of volume thermal expansion in nanowires of Zn, β-Sn, TiO 2 (rutile) is stud

APA, Harvard, Vancouver, ISO, and other styles

43

Sai, V. S., M. R. S. Satyanarayana, V. B. K. Murthy, G. S. Rao, and A. S. Prasad. "An Experimental Simulation to Validate FEM to Predict Transverse Young’s Modulus of FRP Composites." Advances in Materials Science and Engineering 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/648527.

Full text

Abstract:

Finite element method finds application in the analysis of FRP composites due to its versatility in getting the solution for complex cases which are not possible by exact classical analytical approaches. The finite element result is questionable unless it is obtained from converged mesh and properly validated. In the present work specimens are prepared with metallic materials so that the arrangement of fibers is close to hexagonal packing in a matrix as similar arrangement in case of FRP is complex due to the size of fibers. Transverse Young’s moduli of these specimens are determined experimen

APA, Harvard, Vancouver, ISO, and other styles

44

Arakcheeva, Alla, Gervais Chapuis, Vaclav Petříček, Michal Dušek, and Andreas Schönleber. "The incommensurate structure of K3In(PO4)2." Acta Crystallographica Section B Structural Science 59, no. 1 (2003): 17–27. http://dx.doi.org/10.1107/s0108768102021195.

Full text

Abstract:

The incommensurately modulated structure of K3In(PO4)2 has been solved and refined. The origin of the modulation relates to the ordering of K cations within the hexagonal close packing of the PO4 anions. The driving forces for the modulation of the other cations are In—P and K—P interactions. The modulation of O atoms of rigid PO4 units follows the cations in order to stabilize the InO6 octahedron. It is shown that the previously published three-dimensional structure refined from powder diffraction data obtained at room temperature is an average structure. Therefore the incommensurately modula

APA, Harvard, Vancouver, ISO, and other styles

45

Medlin, D. L., and J. C. Hamilton. "Formation of hexagonal close packing at a grain boundary in gold by the dissociation of a dense array of crystal lattice dislocations." Journal of Materials Science 44, no. 13 (2009): 3608–17. http://dx.doi.org/10.1007/s10853-009-3488-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Lotito and Zambelli. "A Journey Through the Landscapes of Small Particles in Binary Colloidal Assemblies: Unveiling Structural Transitions from Isolated Particles to Clusters upon Variation in Composition." Nanomaterials 9, no. 7 (2019): 921. http://dx.doi.org/10.3390/nano9070921.

Full text

Abstract:

Two-dimensional (2D) amorphous binary colloidal assemblies composed of particles of two different sizes are characterized by the loss of hexagonal close-packing for larger particles, occurring when the size ratio between small (S) and large (L) particles dSdL exceeds a certain threshold value. For moderately low particle number ratios NSNL large particles still retain a denser arrangement with transitions from hexagonal symmetry to the coexistence of different types of symmetries as NSNL progressively departs from 0 to higher values. On the other hand, small particles reveal sparser arrangemen

APA, Harvard, Vancouver, ISO, and other styles

47

Harfenist, S. A., Z. L. Wang, I. Vezmar, M. M. Alvarez, and R. L. Whetten. "Growth Mechanism of Ag Nanocrystal Supercrystals." Microscopy and Microanalysis 4, S2 (1998): 732–33. http://dx.doi.org/10.1017/s1431927600023783.

Full text

Abstract:

Of recent interest in the science of nano-scale materials is the production and characterization of substances composed of ordered lattices of up to millions of identical nanometer scale particles. Silver nanocrystals of ∼ 4.5 nm diameter passivated with dodecanthiol surfactant were produced in the aerosol phase. Characterization of the individual particles and the subsequent supercrystals (SXs) resulting from their periodic packing was brought about using Mass Spectrometry, Transmission Electron Microscopy (TEM)/Electron Diffraction (ED), Scanning Electron Microscopy and Atomic Force Microsco

APA, Harvard, Vancouver, ISO, and other styles

48

Su, Xuzhong, and Xinjin Liu. "Theoretical research of spinning triangle division on spun yarn torque." International Journal of Clothing Science and Technology 31, no. 6 (2019): 839–55. http://dx.doi.org/10.1108/ijcst-01-2019-0004.

Full text

Abstract:

Purpose The purpose of this paper is to theoretically study the effects of ring spinning triangle division on spun yarn torques. Design/methodology/approach The case that the spinning triangle is divided into two parts, primary triangles and final triangle, is investigated. Theoretical model of yarn torque was given by linking the fiber tension in the spinning triangle to yarn torque under the assumption that the arrangement of fibers (substrands) in the substrands (yarn) is hexagonal close packing. Then, as an application of the proposed method, 14.6tex cotton yarns were taken as an example f

APA, Harvard, Vancouver, ISO, and other styles

49

Peresypkina, Eugenia V., Mark B. Bushuev, Alexander V. Virovets, Victor P. Krivopalov, Ludmila G. Lavrenova, and Stanislav V. Larionov. "Three differently coloured concomitant polymorphs: synthesis, structure and packing analysis of (4-(3′,5′-dimethyl-1H-pyrazol-1′-yl)-6-methyl-2-phenylpyrimidine)dichlorocopper(II)." Acta Crystallographica Section B Structural Science 61, no. 2 (2005): 164–73. http://dx.doi.org/10.1107/s010876810403294x.

Full text

Abstract:

A novel pyrazolylpyrimidine ligand (L) and its complex CuLCl2 were prepared and structurally characterized. The simultaneous crystallization of three polymorphs of CuLCl2, green (G), emerald green (EG) and orange (O), was discovered. The molecular structures vary only slightly between the three forms. The Cu atom forms four coordinate bonds with the two N and two Cl atoms, and a shortened Cu...H contact with an H atom of the phenyl ring in L. The structural difference between polymorphs was analyzed with the boundary surfaces of molecular Voronoi–Dirichlet polyhedra. The difference in colour o

APA, Harvard, Vancouver, ISO, and other styles

50

Bai, Fengmei, Qingliang Zhu, Jiaming Shen, et al. "Study on Phase Transformation Orientation Relationship of HCP-FCC during Rolling of High Purity Titanium." Crystals 11, no. 10 (2021): 1164. http://dx.doi.org/10.3390/cryst11101164.

Full text

Abstract:

High purity titanium (Ti) thin strip was prepared by rolling with large deformation and was characterized by the means of Transmission Electron Microscopy (TEM), selected area diffraction (SAED) pattern, high-resolution (HRTEM) analysis, as well as Transmission Kikuchi Diffraction (TKD). It is found that there are face-centered cubic (FCC) Ti laths formed within the matrix of hexagonal close packing (HCP) Ti. This shows that the HCP-FCC phase transition occurred during the rolling, and a specific orientation relationship (OR) between HCP phase and FCC phase obeys ⟨0001⟩α// ⟨001⟩FCC and {100}α/

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!