Pore geometry in woven fiber structures: 0°/90° plain-weave cloth layup preform

1998 ◽  
Vol 13 (5) ◽  
pp. 1209-1217 ◽  
Author(s):  
S-B. Lee ◽  
S. R. Stock ◽  
M. D. Butts ◽  
T. L. Starr ◽  
T. M. Breunig ◽  
...  
Keyword(s):  
Gas Flow ◽  
Three Dimensional ◽  
Pore Geometry ◽  
Two Dimensional ◽  
Transverse Distribution ◽  
One Dimensional ◽  
X Ray ◽  
Woven Structures ◽  
Flow Through

Composite preform fiber architectures range from the very simple to the complex, and the extremes are typified by parallel continuous fibers and complicated three-dimensional woven structures. Subsequent processing of these preforms to produce dense composites may depend critically on the geometry of the interfiber porosity. The goal of this study is to fully characterize the structure of a 0°/90° cloth layup preform using x-ray tomographic microscopy (XTM). This characterization includes the measurement of intercloth channel widths and their variability, the transverse distribution of through-cloth holes, and the distribution of preform porosity. The structure of the intercloth porosity depends critically on the magnitude and direction of the offset between adjacent cloth layers. The structures observed include two-dimensional networks of open pipes linking adjacent holes, arrays of parallel one-dimensional pipes linking holes, and relatively closed channels exhibiting little structure, and these different structures would appear to offer very different resistances to gas flow through the preform. These measurements, and future measurements for different fiber architectures, will yield improved understanding of the role of preform structure on processing.

Structure, Magnetic and Ion-Exchange Properties of Self-Assembled Triaza-Copper(II)-Oxalate Hybrides Having Nanoscale One-Dimensional Channel

2006 ◽  
Vol 6 (11) ◽  
pp. 3338-3342 ◽  
Author(s):  
Mee Chang ◽  
Minchul Chung ◽  
Byung Soo Lee ◽  
Chee-Hun Kwak
Keyword(s):  
Magnetic Property ◽  
Three Dimensional ◽  
Antiferromagnetic Interaction ◽  
Two Dimensional ◽  
One Dimensional ◽  
X Ray ◽  
Dimensional Network ◽  
Self Assembled ◽  
Exchange Properties ◽  
Strong Antiferromagnetic Interaction

The X-ray structure, porous and magnetic property of a self-assembled network 1 is described in detail. The single crystal X-ray analysis provides 1 as a three-dimensional network, which contains two-dimensional permanent ring forming nanoscale one-dimensional channels. The inter-replacement of perchlorate and hexafluorophosphate anions in solid 1 proves its porous structure. There is somewhat strong antiferromagnetic interaction (J = −74.1 cm−1) between two copper(II) ions through oxalate bridge and weak antiferromagnetic interaction (J = −5.1 cm−1) through AEP ligand.

CONEX, a program for angular calibration and averaging of two-dimensional powder scattering patterns

2010 ◽  
Vol 43 (2) ◽  
pp. 352-355 ◽  
Author(s):  
Cedric J. Gommes ◽  
Bart Goderis
Keyword(s):  
Three Dimensional ◽  
Two Dimensional ◽  
One Dimensional ◽  
X Ray ◽  
Geometric Distortions ◽  
Calibration Samples

CONEXis a Windows application for converting series of two-dimensional X-ray powder patterns measured on flat two-dimensional detectors into one-dimensional scattering patterns. It is based on the rigorous use of scattering patterns of calibration samples to determine the three-dimensional position of the detector, with respect to the sample and to the beam. This enables correction of the data for geometric distortions, even when the detector is highly tilted and not centred on the beam.

Two new NiII and ZnII metal–organic frameworks of glutarate and 1,4-bis[(2-methyl-1H-imidazol-1-yl)methyl]benzene ligands: syntheses, structures and luminescence sensing properties

2020 ◽  
Vol 76 (2) ◽  
pp. 148-158
Author(s):  
Fang-Hua Zhao ◽  
Zhong-Lin Li ◽  
Shu-Fang Zhang ◽  
Jian-Hui Han ◽  
Mei Zhang ◽  
...  
Keyword(s):  
Metal Organic Frameworks ◽  
Three Dimensional ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
One Dimensional ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Metal Organic ◽  
3D Framework ◽  
Methyl Benzene

Two new metal–organic frameworks (MOFs), namely, three-dimensional poly[diaquabis{μ2-1,4-bis[(2-methyl-1H-imidazol-1-yl)methyl]benzene}bis(μ2-glutarato)dinickel(II)] monohydrate], {[Ni2(C5H6O4)2(C16H18N4)2(H2O)2]·H2O} n or {[Ni2(Glu)2(1,4-mbix)2(H2O)2]·H2O} n , (I), and two-dimensional poly[[{μ2-1,4-bis[(2-methyl-1H-imidazol-1-yl)methyl]benzene}(μ2-glutarato)zinc(II)] tetrahydrate], {[Zn(C5H6O4)(C16H18N4)]·4H2O} n or {[Zn(Glu)(1,4-mbix)]·4H2O} n (II), have been synthesized hydrothermally using glutarate (Glu2−) mixed with 1,4-bis[(2-methyl-1H-imidazol-1-yl)methyl]benzene (1,4-mbix), and characterized by single-crystal X-ray diffraction, IR and UV–Vis spectroscopy, powder X-ray diffraction, and thermogravimetric and photoluminescence analyses. NiII MOF (I) shows a 4-connected 3D framework with point symbol 66, but is not a typical dia network. ZnII MOF (II) displays a two-dimensional 44-sql network with one-dimensional water chains penetrating the grids along the c direction. The solid-state photoluminescence analysis of (II) was performed at room temperature and the MOF exhibits highly selective sensing toward Fe3+ and Cr2O7 2− ions in aqueous solution.

Syntheses, Structures and Photoluminescent Properties of the Two Novel Coordination Polymers [Cd(pydc)2(tu)]n and [Cd2(SO4)(nic)2(tu)1.5(H2O)2]n (pydc = Pyridine-2,3-dicarboxylate, nic = Nicotinate, tu = Thiourea)

2011 ◽  
Vol 66 (5) ◽  
pp. 459-464 ◽  
Author(s):  
Chao Xu ◽  
Sheng-Bo Liu ◽  
Taike Duan ◽  
Qun Chen ◽  
Qian-Feng Zhang
Keyword(s):  
Hydrogen Bonds ◽  
Coordination Polymers ◽  
Room Temperature ◽  
Three Dimensional ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
Hydrothermal Conditions ◽  
One Dimensional ◽  
X Ray ◽  
Dimensional Network

Two novel cadmium coordination polymers, [Cd(pydc)2(tu)]n (1) and [Cd2(SO4)(nic)2(tu)1.5 - (H2O)2]n (2) (pydc = pyridine-2,3-dicarboxylate, nic = nicotinate, tu = thiourea), have been synthesized under hydrothermal conditions and structurally characterized by X-ray diffraction analysis. 1 is a one-dimensional ladder coordination polymer in a two-dimensional network formed by hydrogen bonds. 2 consists of two kinds of Cd(II) centers in different coordination environments connected via nicotinate and sulfate to form a two-dimensional grid network integrated in a three-dimensional framework generated by hydrogen bonds. 2 shows intense fluorescent emission in the solid state at room temperature

scholarly journals Structural and luminescent properties of co-crystals of tetraiodoethylene with two azaphenanthrenes

2020 ◽  
Vol 76 (3) ◽  
pp. 438-442 ◽  
Author(s):  
Yu-Jin Cui ◽  
Feng Su ◽  
Wei-Jun Jin
Keyword(s):  
Solid State ◽  
Room Temperature ◽  
Three Dimensional ◽  
Luminescent Properties ◽  
Two Dimensional ◽  
Halogen Bonds ◽  
One Dimensional ◽  
X Ray ◽  
X Ray Crystallography ◽  
Independent Molecules

Two new co-crystals, tetraiodoethylene–phenanthridine (1/2), 0.5C2I4·C13H9N (1) and tetraiodoethylene–benzo[f]quinoline (1/2), 0.5C2I4·C13H9N (2), were obtained from tetraiodoethylene and azaphenanthrenes, and characterized by IR and fluorescence spectroscopy, elemental analysis and X-ray crystallography. In the crystal structures, C—I...π and C—I...N halogen bonds link the independent molecules into one-dimensional chains and two-dimensional networks with subloops. In addition, the planar azaphenanthrenes lend themselves to π–π stacking and C—H...π interactions, leading to a diversity of supramolecular three-dimensional structural motifs being formed by these interactions. Luminescence studies show that co-crystals 1 and 2 exhibit distinctly different luminescence properties in the solid state at room temperature.

The Role of Chemical Substances in Classic and Modern Sialography Technique and applications

2018 ◽  
Vol 68 (12) ◽  
pp. 2829-2831
Author(s):  
Danisia Haba ◽  
Cristian Budacu ◽  
Mihai Constantin ◽  
Victor Vlad Costan ◽  
Alexandru Nemtoi
Keyword(s):  
Three Dimensional ◽  
Cone Beam ◽  
Prospective Clinical Study ◽  
Two Dimensional ◽  
Chemical Substances ◽  
X Ray ◽  
Time Period ◽  
Plain Image ◽  
Oral And Maxillofacial Surgeon

The purpose of this study was to assess the role of a chemical contrast medium used in plain x ray and CBCT (cone beam computed tomography) sialography imaging in the detection of different changes associated with lesions of salivary glands. 20 subjects were recruited into this prospective clinical study over a 1 year time period. Sialography was performed by an oral and maxillofacial surgeon. A lateral skull plain image was then made and a three-dimensional scanning using a CBCT machine. The imaging volume was centred on the gland of interest. The lateral skull plain images represented the two-dimensional part of the study, and these were used for comparison with the three-dimensional investigation, the CBCT images.

Three-Dimensional and Nonisotropic Effects in the Analysis of Interference Test Data

1976 ◽  
Vol 16 (05) ◽  
pp. 231-234
Author(s):  
R. Rodriguez-Nieto ◽  
R.D. Carter
Keyword(s):  
Gas Flow ◽  
Three Dimensional ◽  
Observation Point ◽  
Two Dimensional ◽  
Dimensional Flow ◽  
Pulse Testing ◽  
Two Dimensional Flow ◽  
Interference Test ◽  
Flow Through ◽  
Interference Tests

Abstract A three-dimensional analytical model is presented for predicting the performance of pressure and flow rate in anisotropic gas reservoirs. The model considers interference effects and restricted flow entry and uses the point-source solution to the equation that describes unsteady-state real-gas flow through porous media. Introduction The assumption of two-dimensional flow through isotropic porous media is frequently found in reservoir studies. Observed pressure behavior often can be matched using a two-dimensional flow model. However, there are some reservoirs for which matching would not be achieved, when reasonable values of the matching parameter are used, if three-dimensional and nonisotropic effects are not accounted for. THEORY It has been found that results obtained for linear or radial gas flow, regarding the gcg product fixed at its initial value, are good approximations to certain solutions that consider the pressure dependence of this product. To extend this treatment to problems of flow in three dimensions, the following development is presented. The pseudopressure drop occurring at any point in a finite, uniform, anisotropic reservoir resulting from a constant real-gas flow rate at a point source is approximated by 24,865 q sc p sc T res m (x, y, z, t) = ------------------------ F......(1) Tsc kh This equation is derived in Appendix A. The fundamental assumption made in the derivation of Eq. 1 is that the viscosity-compressibility product is a constant. Generally, this is not true. However, for some reservoir problems where small changes in pressure are involved, such as those taking place in pressure are involved, such as those taking place in pulse testing and interference tests, this assumption pulse testing and interference tests, this assumption is reasonable. The corresponding pressure drop is given by the following equation, which is derived in Appendix B: iZi m p = ...................................(2) 2pi EXAMPLE Interference data from a hypothetical test are analyzed by a procedure similar to that proposed for two-dimensional flow in oil reservoirs. From these data, a representative value of the porosity in the region between the production well and the observation point is obtained. Three possible observation-point locations are considered to emphasize the influence of three-dimensional and nonisotropic effects. These locations are characterized by their vertical separation with respect to the midpoint of the well-completion interval. The information needed is given in Fig. 1 and Table 1; y (ft) 9840 --------------------------------------------- 4920 ---- - ------ - ------ - -----* PRODUCING WELL 4592 ---- - ------ - ------ - --* OBSERVATION POINTS 0 ---------------------------------------------------->X (ft) 0 7544 8200 16400 Z(ft) -------------------------------------------------- CASE 3 574 ---------------------------* CASE 2 328 ---------------------------* CASE 1 82 ---------------------------* * MIDDLE POINT OF THE COMPLETION INTERVAL 0 -------------------------------------------------- FIG. 1 LOCATION OF THE PRODUCING WELL AND THE OBSERVATION POINTS; INTERFERENCE-TEST EXAMPLE. SPEJ P. 231

Two New Three-Dimensional Networks Constructed on Polyoxovanadates

2007 ◽  
Vol 60 (11) ◽  
pp. 871 ◽  
Author(s):  
Yan-fei Qi ◽  
Dongrong Xiao ◽  
Enbo Wang ◽  
Zhiming Zhang ◽  
Xinlong Wang
Keyword(s):  
Thermogravimetric Analysis ◽  
Rare Case ◽  
Three Dimensional ◽  
Network Connectivity ◽  
Two Dimensional ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
Inorganic Hybrid ◽  
X Ray

To investigate the role of polyoxovanadates in network connectivity, two new organic–inorganic hybrid vanadates with three-dimensional entangled coordination frameworks, namely [Cu2(biim)3V4O12] 1 and [Co2(biim)3V4O12]·4H2O 2 have been synthesized and characterized by infrared (IR), thermogravimetric analysis (TGA), and single-crystal X-ray diffraction. Crystal data for compound 1: triclinic, P-1, a 9.504(2), b 10.650(2), c 11.993(2) Å; α 72.13(3), β 76.02(3), γ 65.40(3)°; V 1041.4(4) Å3, Z 2, R(final) 0.0492. Crystal data for compound 2: triclinic, P-1, a 9.037(3), b 10.577(2), c 11.9470(2) Å; α 87.80(3), β 81.71(3), γ 85.29(3)°; V 1125.8(4) Å3, Z 1, R(final) 0.0774. Compound 1 is a three-dimensional inclined hetero-catenated framework designed from two two-dimensional sub-layers, [Cu(biim)V4O12] and [Cu(biim)2]. Compound 2 is a rare case of a self-catenated ‘ilc’ network that displays an unusual 424·5·63 topology with the binuclear {Co2O4N6} units as eight-connected nodes.

scholarly journals Role of the Li+node in the Li-BH4substructure of double-cation tetrahydroborates

2014 ◽  
Vol 70 (5) ◽  
pp. 871-878 ◽  
Author(s):  
Pascal Schouwink ◽  
Ľubomír Smrčok ◽  
Radovan Černý
Keyword(s):  
Three Dimensional ◽  
Light Metal ◽  
First Principles Calculations ◽  
Eutectic Melting ◽  
One Dimensional ◽  
X Ray ◽  
Multi Phase ◽  
New Compounds ◽  
Li Content

The phase diagram LiBH4–ABH4(A= Rb,Cs) has been screened and revealed ten new compounds LiiAj(BH4)i+j(A= Rb, Cs), withi,jranging between 1 and 3, representing eight new structure types amongst homoleptic borohydrides. An approach based on synchrotron X-ray powder diffraction to solve crystal structures and solid-state first principles calculations to refine atomic positions allows characterizing multi-phase ball-milled samples. The Li-BH4substructure adopts various topologies as a function of the compound's Li content, ranging from one-dimensional isolated chains to three-dimensional networks. It is revealed that the Li+ion has potential as a surprisingly versatile cation participating in framework building with the tetrahydroborate anion BH4as a linker, if the framework is stabilized by large electropositive counter-cations. This utility can be of interest when designing novel hydridic frameworks based on alkaline metals and will be of use when exploring the structural and coordination chemistry of light-metal systems otherwise subject to eutectic melting.

Polymorphic phase transition of a membrane protein - analysis of continuous diffuse electron diffraction intensity

1986 ◽  
Vol 44 ◽  
pp. 166-167
Author(s):  
Douglas L. Dorset ◽  
Andrew K. Massalski
Keyword(s):  
Molecular Sieve ◽  
Three Dimensional ◽  
Pore Geometry ◽  
Two Dimensional ◽  
Diffraction Intensity ◽  
Polymorphic Phase Transition ◽  
E Coli ◽  
Crystallographic Study ◽  
Hexagonal Form ◽  
Polymorphic Forms

Matrix porin, the ompF gene product of E. coli, has been the object of a electron crystallographic study of its pore geometry in an attempt to understand its function as a membrane molecular sieve. Three polymorphic forms have been found for two-dimensional crystals reconstituted in phospholipid, two hexagonal forms with different lipid content and an orthorhombic form coexisting with and similar to the hexagonal form found after lipid loss. In projection these have been shown to retain the same three-fold pore triplet geometry and analyses of three-dimensional data reveal that the small hexagonal and orthorhombic polymorphs have similar structure as well as unit cell spacings.

Sign in / Sign up

Export Citation Format

Share Document