Experimental and Analytical Study of X-Ray Tube Rotor Dynamics

1993 ◽  
Author(s):  
D. A. Nickel ◽  
Charles M. Krousgrill
Keyword(s):  
Acoustic Noise ◽  
Experimental Studies ◽  
Three Dimensional ◽  
Degree Of Freedom ◽  
Response Curves ◽  
Jump Frequency ◽  
Test Fixture ◽  
X Ray ◽  
Response To Change ◽  
The One

Abstract An X-ray tube rotor has been analyzed, using experimental and numerical methods, as a part of an effort to diagnose an intermittent acoustic noise problem. The type of rotor studied is supported by two solid-lubricated angular contact bearings, and operates in a vacuum. Experimental studies of rotor vibration were performed using a test fixture with radio frequency proximity sensors. Coast-down studies indicated the presence of both synchronous and sub-harmonic whirl, along with a tendency for the nature of response to change rapidly during operation. Two ODE (ordinary differential equation) models: a three-dimensional four-degree-of-freedom model and a one-dimensional one-degree-of-freedom model were derived. Large bearing clearances were a significant source of stiffness nonlinearity in both. Direct ODE solution was used to analyze both models. Parametric continuation was also used to find periodic solutions to the one-degree-of-freedom model for different sets of parameter values. The simulations were performed with geometric and stiffness properties representative of the X-ray tube rotor. Small damping was assumed because of the solid lubricant. Direct ODE solutions showed a variety of synchronous and subharmonic periodic motions. Multi-branch frequency response curves were computed using continuation. Qualitative agreement between experimental and numerical results was obtained in terms of tendency to jump, frequency at which multivaluedness was first observed, and existence of subharmonic solutions.

scholarly journals A new Pb(II)-based coordination polymer constructed from a semirigid tricarboxylate ligand: crystal structure and anti-lung cancer activity

2019 ◽  
Vol 42 (1) ◽  
pp. 8-12
Author(s):  
Kun-Ning Yang ◽  
Ke-De Yuan ◽  
Li-Li Jiang ◽  
Yong Zhang
Keyword(s):  
Lung Cancer ◽  
Coordination Polymer ◽  
Ultrasonic Method ◽  
Three Dimensional ◽  
Human Lung Cancer ◽  
X Ray Diffraction ◽  
Dioic Acid ◽  
X Ray ◽  
The One ◽  
Solvothermal Conditions

Abstract Based on a semirigid tricarboxylate ligand 5-((4-carboxyphenoxy)methyl)benzene-1,3-dioic acid (H3L), a new Pb(II)-based coordination polymer formulated as [Pb(HL)(H2O)](H2O) (1) was synthesized under solvothermal conditions and characterized by single-crystal X-ray structural analysis, power X-ray diffraction, and elemental analysis. Compound 1 is a two-dimensional layered structure formed by the connection of the one-dimensional Pb(II)-based secondary building unit chains with the partly deprotonated HL ligands, which are further extended into three-dimensional supermolecular structures through the H-bonds. Furthermore, the size of the as-prepared 1 could be downsized into the nano region through a simple ultrasonic method. Finally, the antilung cancer activities of 1 and the nanosized 1 have been probed via the MTT assay against three human lung cancer cell lines (A549, H1299, and PC9).

scholarly journals Different modes of runaway electron beams generated in high-pressure gases

2021 ◽  
Vol 2064 (1) ◽  
pp. 012001
Author(s):  
V F Tarasenko ◽  
D A Sorokin ◽  
D V Beloplotov ◽  
M I Lomaev ◽  
E Kh Baksht ◽  
...  
Keyword(s):  
High Pressure ◽  
Runaway Electron ◽  
Experimental Studies ◽  
Beam Current ◽  
Current Amplitude ◽  
X Rays ◽  
X Ray ◽  
Beam Current Amplitude ◽  
The One ◽  
Direction Opposite

Abstract This article presents the results of experimental studies of different modes of a runaway electron beam (RAEB) generation in high-pressure gases as well as X-rays caused by it. In particular, the mode with the greatest beam current amplitude, the one with two current pulses, that with the X-ray pulse duration of 100s ns, the mode in which a RAEB propagates in the direction opposite from an anode, and some others are described. The effect of the cathode design and material on the RAEB current amplitude and duration in atmospheric-pressure air is shown. When analyzing the most common modes, the features of the gap breakdown are used.

Inhibitoren der Korrosion 26 Die Struktur der bei der Korrosion von Kupfer in Gegenwart von 2-Aminopyrimidin (Sauerstoff, NaCl, pH 4,1, 22 °C) aufgebauten Schutzschicht/ Corrosion Inhibitors 26 The Structure of the Protecting Coating Formed During the Corrosion of Copper (Oxigen, NaCl, pH 4.1, 22 °C) in the Presence of 2-Aminopyrimidine

1981 ◽  
Vol 36 (8) ◽  
pp. 989-996 ◽  
Author(s):  
L. Horner ◽  
E. Pliefke
Keyword(s):  
Corrosion Inhibitors ◽  
Metallic Copper ◽  
Three Dimensional ◽  
Copper Surface ◽  
The Other ◽  
Exchange Reactions ◽  
X Ray ◽  
Presence And Absence ◽  
The One ◽  
The Individual

Abstract The analysis of the protective coating produced during the corrosion of copper in the presence of 2-aminopyrimidine (2-AP) is consistent with the composition [Cu1+-2-AP-Cl]n. The individual units form a three-dimensional macro-structure via chloride bridging and hydrogen bonding. The assignment of the structure was supported by NMR, IR, UV and magnetic susceptibüity measurements and an X-ray investigation using the Debye- Scherrer powder method. The thermal behaviour of the coating was studied by massspectral and DTA (differential thermal analysis) methods. Radiochemical experiments were carried out using active copper samples (i.e. containing 64Cu), or using added 64CuCl and 64CuCl2 in the corrosion of non-active copper both in the presence and absence of added 2-AP. The results elucidate the exchange reactions at the copper surface between dissolved and metallic components. The equilibrium between Cu2+ and metallic copper on the one hand and 2 Cu1+ ions on the other is central to the problem, as is also the dissociation of the [Cu1+-2-AP-Cl]n complex. The concepts here developed were confirmed by studies of the autoxidation of CuCl and CuO in the presence and absence of 2-AP.

On the one-dimensional recovery and microstructural evaluation of shocked alumina

2006 ◽  
Vol 462 (2074) ◽  
pp. 3197-3212 ◽  
Author(s):  
N.K Bourne ◽  
W.H Green ◽  
D.P Dandekar
Keyword(s):  
Elastic Limit ◽  
Three Dimensional ◽  
Dislocation Interaction ◽  
One Dimensional ◽  
X Ray ◽  
Interaction Mechanisms ◽  
Microstructural Evaluation ◽  
The One

A technique has been developed in the previous work for determining dislocation interaction mechanisms in metals by shocking, unloading, then decelerating and catching part of the target for subsequent examination. This proceeds by using a system of partial momentum traps around the sample. This technique is further refined here, and is then applied to recover brittle targets that, in three-dimensional loading, would fail into a series of fragments. A number of hydrocode design simulations are presented to illustrate the technique, and the results of the experiments are presented. Sectioned targets indicate fracture, and X-ray tomography gives an overview of the volumetric damage. The response of the alumina above and below the elastic limit is highlighted.

scholarly journals DEVELOPMENT OF THE TECHNIQUE FOR CREATING THREE-DIMENSIONAL VIDEO SCENES WHILE BUILDING OBJECTS OF CHEMICAL ENTERPRISES ON TERRITORIES OF KAZAHSTAN

2019 ◽  
Vol 1 (1) ◽  
pp. 259-264
Author(s):  
Tatyana Khlebnikova ◽  
Symbat Aubakirova
Keyword(s):  
Visual Inspection ◽  
3D Model ◽  
Experimental Studies ◽  
Three Dimensional ◽  
Visual Object ◽  
Local Areas ◽  
Photographic Survey ◽  
Entire Object ◽  
Images Processing ◽  
The One

The article is devoted to some issues concerning the improvement of techniques for stages control, while building the objects of chemical enterprises on territories in Kazakhstan. Nowadays, one of the types of control is the one through single photographs obtained by means of digital cam-eras. But, even visual inspection of the entire object is not possible with the application of single im-ages. The authors suggest to conduct aerial photographic survey of an object, photogrammetric im-ages processing, the object or the local areas 3D-model design while performing any work stage or its completion. The Agisoft PhotoScan Programme for experimental studies was chosen. The survey was carried out with Huawei Nova 2i RNE-L21 Graphite Black smartphone. As a result, due to to-photogrammetric images processing, the point digital model, providing visual object correctness was obtained.

A one-dimensional silver(I) coordination polymer based on 5-methyl-1,3,4-thiadiazol-2-amine and pyridine-2,3-dicarboxylate

2017 ◽  
Vol 73 (6) ◽  
pp. 498-502
Author(s):  
Wei-Wei Fu ◽  
Juan Li ◽  
Shu-Ting Liu ◽  
Dan Zhao ◽  
Xue Zhou ◽  
...  
Keyword(s):  
Coordination Polymer ◽  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Binding Modes ◽  
Supramolecular Framework ◽  
X Ray Diffraction ◽  
Tetrahedral Geometry ◽  
One Dimensional ◽  
X Ray ◽  
The One

The bifunctional pyridine-2,3-dicarboxylic acid (H2pdc) ligand has one N atom and four O atoms, which could bind more than one AgI centre with diverse binding modes. A novel infinite one-dimensional AgI coordination polymer, namely catena-poly[[silver(I)-(μ2-pyridine-2,3-dicarboxylato-κ2 N:O 3)-silver(I)-tris(μ2-5-methyl-1,3,4-thiodiazol-2-amine-κ2 N:N′)] monohydrate ethanol monosolvate], {[Ag2(C7H3NO4)(C3H5N3S)3]·H2O·C2H5OH} n , has been synthesized using H2pdc and 5-methyl-1,3,4-thiadiazol-2-amine (tda), and characterized by single-crystal X-ray diffraction. One AgI atom is located in a four-coordinated AgN4 tetrahedral geometry and the other AgI atom is in a tetrahedral AgN3O geometry. A dinuclear AgI cluster formed by three tda ligands with a paddelwheel configuration is bridged by the dianionic pdc2− ligand into a one-dimensional coordination polymer. Interchain N—H...O hydrogen bonds extend the one-dimensional chains into an undulating two-dimensional sheet. The sheets are further packed into a three-dimensional supramolecular framework by interchain N—H...O hydrogen bonds.

The lattice distortion and possible causes of the lazurite incommensurate and commensurate modulation structure

1993 ◽  
Vol 8 (4) ◽  
pp. 202-205
Author(s):  
A. N. Sapozhnikov ◽  
E. K. Vasil'ev
Keyword(s):  
Lattice Distortion ◽  
Three Dimensional ◽  
X Ray Diffraction ◽  
One Dimensional ◽  
X Ray ◽  
Mineral Structure ◽  
Incommensurate Modulation ◽  
Density Modulation ◽  
Cubic Structure ◽  
The One

By methods of X-ray structure analysis commensurate (one dimensional) and incommensurate (three-dimensional) modulations of the lazurite structure from Baikal deposits are considered. The analysis of the X-ray diffraction powder and single crystal data showed that the one-dimensional (anisotropic) modulation deforms the lazurite cubic structure and is manifested in a broadening and splitting of sublattice lines on the powder diffraction pattern of the mineral. At a three-dimensional modulation, the cubic structure is maintained. It is concluded that a density modulation is a cause of the incommensurate modulation of the lazurite structure. Due to this arrangement, a crystallographic equivalency of subcells is maintained. The cause of the commensurate modulation is an ordered distribution of intraframework units and the displacement modulation where all atoms of the mineral structure participate.

A one-dimensional coordination polymer createdvia in situligand synthesis involving C—N bond formation

2013 ◽  
Vol 69 (11) ◽  
pp. 1307-1310 ◽  
Author(s):  
Hua Cai ◽  
Ying Guo ◽  
Jian-Gang Li
Keyword(s):  
Addition Reaction ◽  
Bond Formation ◽  
Three Dimensional ◽  
Cadmium Complex ◽  
Stacking Interactions ◽  
The Novel ◽  
X Ray Diffraction ◽  
One Dimensional ◽  
X Ray ◽  
The One

The novel cadmium complexcatena-poly[cadmium(II)-μ3-{2-[3-(pyridin-2-yl)-1H-pyrazol-1-yl]butanedioato}], [Cd(C12H9N3O4)]n, has been prepared by the conjugate addition reaction of 2-(1H-pyrazol-3-yl)pyridine to fumaric acid in the presence of Cd(OAc)2·3H2O (OAc is acetate) at 413 K. Single-crystal X-ray diffraction analysis reveals that the complex consists of one-dimensional ladders constructed from [Cd2(COO)2] dimeric subunits. A combination of hydrogen bonding and π–π stacking interactions extend the one-dimensional ladders into a three-dimensional supramolecular architecture.

Ribosome Structural Organization

1974 ◽  
Vol 32 ◽  
pp. 332-333
Author(s):  
James A. Lake
Keyword(s):  
Ribosomal Proteins ◽  
Structural Organization ◽  
Three Dimensional ◽  
Small Subunit ◽  
Structural Studies ◽  
X Ray Diffraction ◽  
Specific Antibodies ◽  
X Ray ◽  
E Coli ◽  
Complete Sequences

The understanding of ribosome structure has advanced considerably in the last several years. Biochemists have characterized the constituent proteins and rRNA's of ribosomes. Complete sequences have been determined for some ribosomal proteins and specific antibodies have been prepared against all E. coli small subunit proteins. In addition, a number of naturally occuring systems of three dimensional ribosome crystals which are suitable for structural studies have been observed in eukaryotes. Although the crystals are, in general, too small for X-ray diffraction, their size is ideal for electron microscopy.

3-D reconstruction of molecular shape from microcrystal thin sections

1983 ◽  
Vol 41 ◽  
pp. 748-749
Author(s):  
S. Cusack ◽  
J.-C. Jésior
Keyword(s):  
Three Dimensional ◽  
Molecular Shape ◽  
Biological Molecules ◽  
Fourier Space ◽  
Single Particles ◽  
Thin Sections ◽  
Standard Methods ◽  
X Ray ◽  
X Ray Crystallography ◽  
Dimensional Reconstruction

Three-dimensional reconstruction techniques using electron microscopy have been principally developed for application to 2-D arrays (i.e. monolayers) of biological molecules and symmetrical single particles (e.g. helical viruses). However many biological molecules that crystallise form multilayered microcrystals which are unsuitable for study by either the standard methods of 3-D reconstruction or, because of their size, by X-ray crystallography. The grid sectioning technique enables a number of different projections of such microcrystals to be obtained in well defined directions (e.g. parallel to crystal axes) and poses the problem of how best these projections can be used to reconstruct the packing and shape of the molecules forming the microcrystal.Given sufficient projections there may be enough information to do a crystallographic reconstruction in Fourier space. We however have considered the situation where only a limited number of projections are available, as for example in the case of catalase platelets where three orthogonal and two diagonal projections have been obtained (Fig. 1).

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