scholarly journals A simple method to characterize high rate twin boundary kinetics in Ni-Mn-Ga

2019 ◽  
Vol 90 (10) ◽  
pp. 105107
Author(s):  
Bibek Karki ◽  
Yotam Behar ◽  
Itai Harel ◽  
Eitan Caplan ◽  
Arik Sabbag ◽  
...  
Keyword(s):  
Twin Boundary ◽  
High Rate ◽  
Simple Method ◽  
Boundary Kinetics

scholarly journals A rhythm landscape approach to the developmental dynamics of birdsong

2015 ◽  
Vol 12 (112) ◽  
pp. 20150802 ◽  
Author(s):  
Kazutoshi Sasahara ◽  
Ofer Tchernichovski ◽  
Miki Takahasi ◽  
Kenta Suzuki ◽  
Kazuo Okanoya
Keyword(s):  
Crystallization Process ◽  
Biological Rhythms ◽  
High Rate ◽  
Temporal Constraints ◽  
Landscape Approach ◽  
Simple Method ◽  
Information Theoretic ◽  
Behavioural Biology ◽  
Developmental Dynamics ◽  
Jensen Shannon Divergence

Unlike simple biological rhythms, the rhythm of the oscine bird song is a learned time series of diverse sounds that change dynamically during vocal ontogeny. How to quantify rhythm development is one of the most important challenges in behavioural biology. Here, we propose a simple method, called ‘rhythm landscape’, to visualize and quantify how rhythm structure, which is measured as durational patterns of sounds and silences, emerges and changes over development. Applying this method to the development of Bengalese finch songs, we show that the rhythm structure begins with a broadband rhythm that develops into diverse rhythms largely through branching from precursors. Furthermore, an information-theoretic measure, the Jensen–Shannon divergence, was used to characterize the crystallization process of birdsong rhythm, which started with a high rate of rhythm change and progressed to a stage of slow refinement. This simple method provides a useful description of rhythm development, thereby helping to reveal key temporal constraints on complex biological rhythms.

Effect of uridine on the incorporation of thymine and thymidine in Escherichia coli

1973 ◽  
Vol 19 (4) ◽  
pp. 485-490 ◽  
Author(s):  
R. M. Behki ◽  
S. M. Lesley
Keyword(s):  
Escherichia Coli ◽  
Dna Synthesis ◽  
Cell Cultures ◽  
Inhibitory Effect ◽  
High Rate ◽  
Simple Method ◽  
Initial Concentration ◽  
Intact Molecule

Uridine inhibits the incorporation of thymine in Escherichia coli 15T− cells but the duration of this inhibition is dependent upon the initial concentration of uridine and its rate of degradation. Uridine is rapidly degraded to uracil and the completion of this degradation coincides with the release of the inhibitory effect. However, uridine, by preventing the phosphorolysis of thymidine, allows the continued incorporation of the intact molecule at the initial high rate for as long as the concentration of undegraded uridine remains above a certain level. In resuspended 15T− cells, this rate is the same, irrespective of the presence or absence of uridine. The results presented here provide a simple method of controlling DNA synthesis, as represented by thymine incorporation, without the addition of inhibitors or other manipulations of the cell cultures.

Brittle Point of Rubber on Freezing

1942 ◽  
Vol 15 (2) ◽  
pp. 243-250
Author(s):  
M. L. Selker ◽  
G. G. Winspear ◽  
A. R. Kemp
Keyword(s):  
Low Temperatures ◽  
High Rate ◽  
Simple Method ◽  
Vulcanized Rubber ◽  
Synthetic Rubber ◽  
Brittle Point ◽  
New Material ◽  
Point Data ◽  
First Time

Abstract The need for a simple method of determining brittle points which would be adaptable to a large number of materials led the writers to develop the apparatus described below. There is presented here, for the first time, brittle point data on certain natural and synthetic rubber compositions. The study of the variation with temperature of the mechanical properties of elastomers is of immediate practical and theoretical interest. Recently Kistler attempted a correlation of temperature-strength data of polymers with their chemical structure. On the other hand, the increasing use of synthetic high polymers at low temperatures for insulation and mechanical purposes requires a more complete knowledge of their behavior under conditions of extreme cold. The determination of the brittle point offers a simple method for investigating the possible use of a new material at low temperatures. In 1928 Kohman and Peek described a method whereby a small strip of material at a known temperature was bent quickly through 90° by a hammer blow. They found that within rather wide limits the brittle temperature was independent of the sample dimensions and bending angle, but that a high rate of deformation was necessary for reproducible results. The brittle point was found to be definite and reproducible within ±2° C for the materials studied. Using this method, Kemp determined the brittle point range of crude and vulcanized rubber, balata, guttapercha, and paragutta.

Simple in situ synthesis of carbon-supported and nanosheet-assembled vanadium oxide for ultra-high rate anode and cathode materials of lithium ion batteries

2016 ◽  
Vol 4 (36) ◽  
pp. 13907-13915 ◽  
Author(s):  
Xingchao Wang ◽  
Wei Jia ◽  
Luxiang Wang ◽  
Yudai Huang ◽  
Yong Guo ◽  
...  
Keyword(s):  
Vanadium Oxide ◽  
Lithium Ion Batteries ◽  
Cathode Materials ◽  
Lithium Ion ◽  
In Situ Synthesis ◽  
High Rate ◽  
Simple Method

In situ carbon supported V2O5 nanosheets were synthesized by a simple method and showed excellent anode and cathode capacity for LIBs.

Structure of Palladium Single-Crystal Films Prepared by Flash Evaporation onto (001) NaCl Substrates

1970 ◽  
Vol 28 ◽  
pp. 456-457
Author(s):  
L. E. Murr ◽  
G. Wong
Keyword(s):  
Single Crystal ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
High Rate ◽  
Flash Evaporation ◽  
Optimum Load ◽  
Single Crystal Films ◽  
Crystal Films ◽  
A Current

Palladium single-crystal films have been prepared by Matthews in ultra-high vacuum by evaporation onto (001) NaCl substrates cleaved in-situ, and maintained at ∼ 350° C. Murr has also produced large-grained and single-crystal Pd films by high-rate evaporation onto (001) NaCl air-cleaved substrates at 350°C. In the present work, very large (∼ 3cm2), continuous single-crystal films of Pd have been prepared by flash evaporation onto air-cleaved (001) NaCl substrates at temperatures at or below 250°C. Evaporation rates estimated to be ≧ 2000 Å/sec, were obtained by effectively short-circuiting 1 mil tungsten evaporation boats in a self-regulating system which maintained an optimum load current of approximately 90 amperes; corresponding to a current density through the boat of ∼ 4 × 104 amperes/cm2.

A simple way for producing holographic filters suitable for image improvement

1978 ◽  
Vol 36 (1) ◽  
pp. 226-227
Author(s):  
K.-H. Herrmann ◽  
E. Reuber ◽  
P. Schiske
Keyword(s):  
Transfer Functions ◽  
Diffraction Order ◽  
Lateral Position ◽  
Simple Method ◽  
Spatial Frequencies ◽  
Resolution Electron ◽  
Wiener Filters ◽  
Image Improvement ◽  
Optical Reconstruction ◽  
Set Up

Aposteriori deblurring of high resolution electron micrographs of weak phase objects can be performed by holographic filters [1,2] which are arranged in the Fourier domain of a light-optical reconstruction set-up. According to the diffraction efficiency and the lateral position of the grating structure, the filters permit adjustment of the amplitudes and phases of the spatial frequencies in the image which is obtained in the first diffraction order.In the case of bright field imaging with axial illumination, the Contrast Transfer Functions (CTF) are oscillating, but real. For different imageforming conditions and several signal-to-noise ratios an extensive set of Wiener-filters should be available. A simple method of producing such filters by only photographic and mechanical means will be described here.A transparent master grating with 6.25 lines/mm and 160 mm diameter was produced by a high precision computer plotter. It is photographed through a rotating mask, plotted by a standard plotter.

Rotary Beveling for In Situ Thin-Section Microscopy of Cell Cultures

1981 ◽  
Vol 39 ◽  
pp. 550-551
Author(s):  
Dean A. Handley ◽  
Jack T. Alexander ◽  
Shu Chien
Keyword(s):  
Cell Growth ◽  
Cell Cultures ◽  
Molecular Interactions ◽  
Convenient Method ◽  
Petri Dish ◽  
Simple Method ◽  
Thin Section Microscopy ◽  
Thin Sectioning ◽  
Organic Fluids

In situ preparation of cell cultures for ultrastructural investigations is a convenient method by which fixation, dehydration and embedment are carried out in the culture petri dish. The in situ method offers the advantage of preserving the native orientation of cell-cell interactions, junctional regions and overlapping configurations. In order to section after embedment, the petri dish is usually separated from the polymerized resin by either differential cryo-contraction or solvation in organic fluids. The remaining resin block must be re-embedded before sectioning. Although removal of the petri dish may not disrupt the native cellular geometry, it does sacrifice what is now recognized as an important characteristic of cell growth: cell-substratum molecular interactions. To preserve the topographic cell-substratum relationship, we developed a simple method of tapered rotary beveling to reduce the petri dish thickness to a dimension suitable for direct thin sectioning.

Twin boundary structure of a Y-Ba-Cu-O superconductor

1989 ◽  
Vol 47 ◽  
pp. 168-169
Author(s):  
Yimei Zhu ◽  
Masaki Suenaga ◽  
R. L. Sabatini ◽  
Youwen Xu
Keyword(s):  
Twin Boundary ◽  
Fine Particles ◽  
Imaging Techniques ◽  
Fine Powder ◽  
Orthorhombic Phase ◽  
Boundary Structure ◽  
Crystallographic Axis ◽  
System A ◽  
High Resolution Structure ◽  
Electron Microscopes

The (110) twin structure of YBa2Cu3O7 superconductor oxide, which is formed to reduce the strain energy of the tetragonal to orthorhombic phase transformation by alternating the a-b crystallographic axis across the boundary, was extensively investigated. Up to now the structure of the twin boundary still remained unclear. In order to gain insight into the nature of the twin boundary in Y-Ba-Cu-O system, a study using electron diffraction techniques including optical and computed diffractograms, as well as high resolution structure imaging techniques with corresponding computer simulation and processing was initiated.Bulk samples of Y-Ba-Cu-O oxide were prepared as described elsewhere. TEM specimens were produced by crushing bulk samples into a fine powder, dispersing the powder in acetone, and suspending the fine particles on a holey carbon grid. The electron microscopy during this study was performed on both a JEOL 2000EX and 2000FX electron microscopes operated at 200 kV.

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