Thermal Acclimation of a Central Neurone in Helix Aspersa: III. Ionic Substitution and Related Studies

1979 ◽  
Vol 78 (1) ◽  
pp. 201-211
Author(s):  
C. K. LANGLEY
Keyword(s):  
Chemical Composition ◽  
Electrical Properties ◽  
Membrane Resistance ◽  
Thermal Acclimation ◽  
Neuronal Membrane ◽  
Electrical Characteristics ◽  
Ionic Substitution ◽  
Warm Acclimation ◽  
Sodium And Potassium ◽  
Made In

(1) Thermal acclimation of the Fi neurone does not appear to result from changes in the chemical composition of the haemolymph. This is deduced from the lack of effect on the electrical characteristics of control neurones of either pooled haemolymph from acclimated individuals, or variations in the experimental salines made in accordance with haemolymph analyses. (2) Changes in [Ca]0 tended to act cooperatively with temperature shifts to induce alterations in the electrical properties of the neurone, notably to increase excitability and lower membrane resistance. (3) Warm acclimation was associated with increased resting conductance of the neuronal membrane to sodium and potassium, whereas chloride conductance appeared little affected.

In situ TEM measurements of the electrical properties of interface dislocations

1992 ◽  
Vol 50 (2) ◽  
pp. 1338-1339
Author(s):  
F. M. Ross ◽  
R. Hull ◽  
D. Bahnck ◽  
J. C. Bean ◽  
L. J. Peticolas ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Electronic Device ◽  
In Situ Tem ◽  
Device Performance ◽  
Misfit Dislocations ◽  
Electrical Characteristics ◽  
Strained Layer ◽  
Transmission Electron ◽  
Interfacial Dislocations

We describe an investigation of the electrical properties of interfacial dislocations in strained layer heterostructures. We have been measuring both the structural and electrical characteristics of strained layer p-n junction diodes simultaneously in a transmission electron microscope, enabling us to correlate changes in the electrical characteristics of a device with the formation of dislocations.The presence of dislocations within an electronic device is known to degrade the device performance. This degradation is of increasing significance in the design and processing of novel strained layer devices which may require layer thicknesses above the critical thickness (hc), where it is energetically favourable for the layers to relax by the formation of misfit dislocations at the strained interfaces. In order to quantify how device performance is affected when relaxation occurs we have therefore been investigating the electrical properties of dislocations at the p-n junction in Si/GeSi diodes.

The morphologies and electrical properties of indium contacts on (100) cadmium telluride surfaces

1992 ◽  
Vol 50 (2) ◽  
pp. 1422-1423
Author(s):  
A.M. Letsoalo ◽  
M.E. Lee ◽  
E.O. de Neijs
Keyword(s):  
Electrical Properties ◽  
Cadmium Telluride ◽  
Methanol Solution ◽  
Electrical Characteristics ◽  
Metal Contacts ◽  
Deposition Technique ◽  
Interfacial Layers ◽  
Semiconductor Contacts ◽  
Grown Single Crystal ◽  
Diamond Abrasive

Semiconductor devices require metal contacts for efficient collection of electrical charge. The physics of these metal/semiconductor contacts assumes perfect, abrupt and continuous interfaces between the layers. However, in practice these layers are neither continuous nor abrupt due to poor nucleation conditions and the formation of interfacial layers. The effects of layer thickness, deposition rate and substrate stoichiometry have been previously reported. In this work we will compare the effects of a single deposition technique and multiple depositions on the morphology of indium layers grown on (100) CdTe substrates. The electrical characteristics and specific resistivities of the indium contacts were measured, and their relationships with indium layer morphologies were established.Semi-insulating (100) CdTe samples were cut from Bridgman grown single crystal ingots. The surface of the as-cut slices were mechanically polished using 5μm, 3μm, 1μm and 0,25μm diamond abrasive respectively. This was followed by two minutes immersion in a 5% bromine-methanol solution.

Effect of H2S pre-annealing treatment on interfacial and electrical properties of HfO2/Si1−xGex (x = 0-0.3)

2021 ◽  
Author(s):  
Woohui Lee ◽  
Changmin Lee ◽  
Jinyong Kim ◽  
Jehoon Lee ◽  
Deokjoon Eom ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Annealing Treatment ◽  
Atomic Layer ◽  
Alloy Film ◽  
Electrical Characteristics

To understand the effect of H2S pre-annealing treatment on a Si1-xGex alloy film, the interfacial and electrical characteristics of atomic-layer-deposited HfO2/Si1-xGex were studied while varying the Ge concentration (x value)...

scholarly journals Electrical Impedance Spectroscopy as Electrical Biopsy for Monitoring Radiation Sequelae of Intestine in Rats

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Pei-Ju Chao ◽  
Eng-Yen Huang ◽  
Kuo-Sheng Cheng ◽  
Yu-Jie Huang
Keyword(s):  
Electrical Properties ◽  
Impedance Spectroscopy ◽  
Integrated Circuits ◽  
Electrical Impedance ◽  
Roc Analysis ◽  
Electrical Impedance Spectroscopy ◽  
Electrical Characteristics ◽  
Injury Score ◽  
Histological Changes ◽  
Radiation Sequelae

Electrical impedance is one of the most frequently used parameters for characterizing material properties. The resistive and capacitive characteristics of tissue may be revealed by electrical impedance spectroscopy (EIS) as electrical biopsy. This technique could be used to monitor the sequelae after irradiation. In this study, rat intestinal tissues after irradiation were assessed by EIS system based on commercially available integrated circuits. The EIS results were fitted to a resistor-capacitor circuit model to determine the electrical properties of the tissue. The variations in the electrical characteristics of the tissue were compared to radiation injury score (RIS) by morphological and histological findings. The electrical properties, based on receiver operation curve (ROC) analysis, strongly reflected the histological changes with excellent diagnosis performance. The results of this study suggest that electrical biopsy reflects histological changes after irradiation. This approach may significantly augment the evaluation of tissue after irradiation. It could provide rapid results for decision making in monitoring radiation sequelae prospectively.

Electrical Characteristics of the Membrane Of An Identified Insect Motor Neurone

1980 ◽  
Vol 86 (1) ◽  
pp. 49-61
Author(s):  
G. F. GWILLIAM ◽  
M. BURROWS
Keyword(s):  
Electrical Properties ◽  
Conduction Velocity ◽  
Average Velocity ◽  
Motor Neurone ◽  
Electrical Characteristics ◽  
Initiation Zone ◽  
Active Membrane ◽  
Metathoracic Ganglion ◽  
Different Parts

1. The electrical properties of the membrane of an identified locust motor neurone, the fast extensor tibiae in the metathoracic ganglion, have been investigated to determine: the distribution of excitable and inexcitable membrane; the impulse initiation zone; and the conduction velocity of the spike in the ganglion and in the axon. 2. The waveform of extracellularly recorded spikes indicates that the transition from inactive to active membrane occurs along the region of the neurite which bears many arborizations within the neuropile. 3. Measurements of the delay between orthodromically or antidromically evoked spikes, recorded at the soma and other points along the neurite, place the impulse initiating zone close to the transition between active and inactive membrane. 4. Within the ganglion, the spike is conducted at different velocities over different parts of the neurite. The average velocity within the ganglion is, however, only about a seventh of that in the axon (0.54 m.s−1 against 4.1 m.s−1).

Optical, Structural and Electrical Characteristics of Explosively Crystallized Si Thin Films on Glass Substrates

1981 ◽  
Vol 4 ◽  
Author(s):  
G. Auvert ◽  
D. Bensahel ◽  
A. Perio ◽  
F. Morin ◽  
G.A. Rozgonyi ◽  
...  
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Laser Annealing ◽  
The State ◽  
Electrical Characteristics ◽  
Glass Substrates ◽  
Explosive Crystallization ◽  
Cw Laser ◽  
Structural And Electrical Properties ◽  
Si Films

ABSTRACTExplosive Crystallization occurs in cw laser annealing on a-Si films deposited on glass substrates at laser scan speeds higher than 30 cm/sec. Optical, structural and electrical properties of the crystallized films at various laser scan speeds confirm the existence of two kinds of explosive growth depending on the state of crystallinity of the starting material.

scholarly journals Вплив параметрів адитивного формування на електричні властивості графітонаповненого композиту на основі полілактиду

2021 ◽  
Vol 150 (5) ◽  
pp. 93-102
Author(s):  
Н. В. Сова ◽  
О. О. Слепцов ◽  
Т. Р. Федорів ◽  
А. О. Мартиненко ◽  
М. Р. Кудлай ◽  
...  
Keyword(s):  
Electrical Properties ◽  
3D Printing ◽  
Electrical Resistance ◽  
Specific Resistance ◽  
Polymer Melt ◽  
Electrical Characteristics ◽  
Additive Production ◽  
Filled Composite ◽  
Printing Parameters ◽  
Bulk Electrical Resistance

Purpose. Investigate the effect of additive formation parameters on the properties of an antistatic composition based on polylactide (PLA). Methodology. Surface and bulk electrical resistance were determined by ASTM D257. Findings. The influence of additive formation parameters on the electrical properties of graphite-filled composite based on polylactide has been studied. It was found that the value of resistivity significantly depends on the printing conditions, namely the temperature, speed, thickness of the layer. Increasing the printing temperature helps to reduce the resistivity of the sample. Reducing the thickness of the polymer layer also reduces the resistivity at a print speed within 3000 mm / min It was found that the specific electrical characteristics are significantly different in the plane of the sample in contact with the printing platform. Concentric method of laying layers of polymer melt is less effective in terms of resistivity than mutually perpendicular. It was found that the electrical resistivity of samples made of material for 3D printing, which was previously subjected to drying below the resistance of the sample made of undried material. The programmed change of 3D printing parameters allows to control the specific resistance of graphite-filled composite based on polylactide in the range of three orders and to obtain products with properties from antistatic to statically dissipative materials. Additive production allows to obtain products of the desired configuration with adjustable electrical properties. Originality. The peculiarities of the change of antistatic properties of the polymer composite depending on the conditions of additive formation of experimental samples are investigated. Depending on the applied parameters of additive molding, it is possible to obtain products with properties from antistatic to statically dissipative materials. Practical value. Technological modes of additive molding of composite products based on polylactide and graphite have been developed. Energy consumption for additive formation of products of different mass is estimated.

scholarly journals THE COMPARATIVE VIABILITY OF PNEUMOCOCCI ON SOLID AND ON FLUID CULTURE MEDIA

1913 ◽  
Vol 18 (5) ◽  
pp. 584-590
Author(s):  
L. J. Gillespie
Keyword(s):  
Chemical Composition ◽  
Solid Medium ◽  
Culture Media ◽  
The Body ◽  
The Other ◽  
Made In ◽  
Fluid Culture

1. Pneumococci, when freshly isolated from the body, are able to live and multiply when a small number of them are inoculated into a small amount of broth. If, however, the inoculations are made in large amounts of broth, many more bacteria must be inoculated in order that they may grow. 2. It requires much smaller numbers of pneumococci to start a growth on agar than are required to start a growth in broth. 3. This predilection for solid medium disappears when the bacteria are grown for some time outside the body. 4. This phenomenon is not dependent on differences in chemical composition between the two media employed or on the presence of more available oxygen in one case than in the other. 5. It is probably dependent entirely on physical differences in the two kinds of media, and bears some relation to the differences in possibilities for diffusion in the two media.

STUDYING MULTILAYERED GRAPHENES BY ELECTROPHYSICAL METHODS

2021 ◽  
pp. 100-107
Author(s):  
K. L. Levine ◽  
D. V. Ryabokon ◽  
S. D. Khanin ◽  
R. V. Gelamo ◽  
N. A. Nikonorova
Keyword(s):  
Electrical Conductivity ◽  
Chemical Composition ◽  
Electrical Properties ◽  
Work Function ◽  
Electron Work Function ◽  
Charge Storage ◽  
High Electrical Conductivity ◽  
Free Standing ◽  
Storage Devices

The paper studies multilayer graphenes in the form of free-standing films. The authors provide data about the morphology and electrical properties of films treated with plasma of various chemical composition. It is shown that it is possible to control the electrical properties of the surface and electron work function without significantly affecting its morphology. The obtained samples, combining mechanical flexibility with unreactiveness and high electrical conductivity, are promising for application in flexible charge storage devices.

Separation of sodium and potassium ion carrier systems in crustacean motor axon

1962 ◽  
Vol 202 (5) ◽  
pp. 856-864 ◽  
Author(s):  
Ernest B. Wright ◽  
Tadao Tomita
Keyword(s):  
Membrane Resistance ◽  
The Other ◽  
Motor Axon ◽  
Potassium Ions ◽  
High Potassium ◽  
Rich Media ◽  
Inward Currents ◽  
Ion Carrier ◽  
Carrier Systems ◽  
Sodium And Potassium

When a microscopic area (100 µ length) of the lobster single motor axon is subjected to isotonic potassium solution and the membrane potential maintained at resting level by an applied voltage, a slow prolonged depolarization may be elicited by adequate cathodal stimuli. This response is due to activity of the potassium carrier system. If some sodium chloride is included in the high potassium solution, both spike and prolonged depolarization may be initiated as a spike-dip-plateau. With normal amount of sodium in excess potassium solution the dip is absent, but the membrane resistance shows a remarkable increase at the juncture of the spike and the plateau. Chronaxie values of the spike are 0.4–0.5 msec, of the slow response 2.1–2.2 msec. In potassium-rich media containing sodium two separate inward currents are recorded during a voltage clamp, an early spikelike current, and a late prolonged one. It is concluded that two separate ion carrier systems are activated in a nerve membrane during excitation, one specific to sodium ions, the other to potassium ions, each system possessing quite different and independent characteristics from the other.

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