scholarly journals The comparative power of alcohol, ether, and chloroform as measured by their action upon isolated muscle

1909 ◽  
Vol 81 (551) ◽  
pp. 545-558 ◽  
Keyword(s):  
Normal Saline ◽  
Tap Water ◽  
Volume Of Fluid ◽  
Secondary Coil ◽  
Sartorius Muscle ◽  
Run Off ◽  
In Series ◽  
Set Up ◽  
Fine Copper ◽  
Careful Comparison

The object of the following communication is twofold: (1) to present the results of a careful comparison of the physiological effectiveness of certain narcotics, and (2) to illustrate the degree of accuracy of which such comparisons are susceptible by the systematic use of the sartorius muscle of the frog as an indicator. Method .—The two sartorius muscles of a frog are dissected out and the portions of bone to which they are attached are ligatured with fine copper wires serving as conductors. The muscles are set up in the two vessels V, V and connected with two myographic levers that record their movements on two smoked plates L, R. The connections with the secondary coil of an inductorium (Berne model) are as given in the diagram, so that both muscles are traversed in series by the same current in the same direction. The muscles are directly excited once every 10 seconds by maximal break induction shocks. Each observation consists of three parts: a first part consisting of the normal responses of the muscle immersed in normal saline (0·6 per 100 NaCl in tap water); a second part consisting of the responses while the muscle is immersed in an experimental solution; a third part consisting of the responses while the muscle is replaced in normal saline. The solutions are changed by being run off through a tap and run in from a pipette, care being taken that the volume of fluid is always the same. The induction currents are kept going automatically throughout an experiment, excepting during the short periods required for changing the solution. The apparatus used for this purpose consists of: (1) a Berne coil fed by a 2-volt accumulator; (2) a Brodie clock with interruptions set at six per minute; and (3) a relay key, i. e. that shown by G. R. Mines at the July, 1908, meeting of the Physiological Society.

scholarly journals Photogrammetric and Satellite Mapping of the Margin of the Inland Ice, West Greenland

1986 ◽  
Vol 8 ◽  
pp. 164-167 ◽  
Author(s):  
H.H. Thomsen
Keyword(s):  
Surface Feature ◽  
Aerial Photographs ◽  
Water Drainage ◽  
Feature Maps ◽  
Hydro Power ◽  
Surface Features ◽  
Power Stations ◽  
Run Off ◽  
Set Up ◽  
Inland Ice

Glaciological investigations have been carried out in areas proposed for local hydro-power stations in Greenland, A mapping programme was set up, to provide data for mass balance and simulation of run-off, as well as glacier dynamics.Two types of glacier map have been produced, covering the margin of the Inland Ice: detailed photogrammetric maps, based on plotting from vertical aerial photographs and a new type of surface feature map, based on digitally-processed Landsat data. The photogrammetric maps, plotted on a scale of 1:25 000, include surface topography and surface features, such as crevasses, lakes, moraines etc. The surface feature maps, plotted on a scale of 1:100 000, show surface features related to ice and melt-water drainage, as well as subtle, topographic features, related to the subglacial topography.The maps have so far been used for preliminary delineation of drainage areas on the Inland Ice and for planning tracks of radio echo-soundings.

scholarly journals Impact of Component Dispersion in DC to DC Low-Power Low-Voltage Power Converter Array

Electronics ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 917
Author(s):  
Jean-Christophe CREBIER ◽  
Theo LAMORELLE ◽  
Silvain MARACHE ◽  
Thanh Hai PHUNG ◽  
Van-Sang NGUYEN ◽  
...  
Keyword(s):  
Closed Loop ◽  
Low Voltage ◽  
Power Converter ◽  
Point Of View ◽  
Statistical Point ◽  
Loop Control ◽  
In Series ◽  
And Performance ◽  
Set Up ◽  
The Impact

The paper deals with arrays of numerous power conversion cells, associated in series and/or in parallel to build larger step up or step down direct current (DC)/DC isolated converters. The work focuses on the impact of the spread and distribution of the conversion cell characteristics on the characteristics and performance of the power converter array (PCA). Based on a characterization protocol, about 130 conversion standard cells (CSC) are characterized and classified from a statistical point of view. Three families are defined and representatives are chosen and implemented in various configurations, in open and closed loop control, to analyze the impact of their spread characteristic over the global converter, the PCA. The paper is based on an extended practical set up and protocols, all described in details. Guidelines on CSCs implementation with respect to their dispersion are provided at the end on the paper.

Sheet Hemming with Rolling Tools: Analysis and Optimization of the Part Quality

2007 ◽  
Vol 344 ◽  
pp. 357-364 ◽  
Author(s):  
Elisabetta Ceretti ◽  
Aldo Attanasio ◽  
Antonio Fiorentino ◽  
Claudio Giardini
Keyword(s):  
Tool Path ◽  
Outer Part ◽  
Experimental Tests ◽  
Process Time ◽  
Cnc Machine ◽  
Whole Process ◽  
Cad Cam ◽  
In Series ◽  
Aluminium Sheets ◽  
Set Up

The present paper is the continuation of a research conducted on hemming operations by using rolling tools. Sheet hemming is a joining operation widely used in automotive industry when it is necessary to join two sheet parts (such as the engine hood or the door panels with their internal frame) by plastic deformation of the edge of the outer part. The whole process is characterised by a 90° sheet flanging, a pre-hemming (up to approximately 135°) and the final hemming where the outer sheet edge is bended up to 180° clamping the inner sheet. Hemming processes are normally performed using rigid dies in series production and manually in pre-series and small batch production, due to the high cost of the dies. Nowadays, rollers moved by robots are becoming an interesting alternative to the manual operations especially when flexible productions are required. Even if the process time is higher, this solution can help in minimizing set-up times and costs. The required equipments are a support and a blocking system for the sheets together with the rollers mounted on a CNC machine or on a robot. The production flexibility is guaranteed by changing the 3D tool path using a CAD/CAM system. Authors are dealing with this technique having conducted many experiments studying the influence of the hemming process parameters such as flange geometry (edge height, fillet radius), distance of the inner panel from the flange, tool path sequence, along straight paths on steel sheets. The goal of the present research is to study the material behaviour and the produced parts quality when working on aluminium sheets. In particular, both experimental tests and simulations will be carried out in order to optimize the process.

How grass contributes to controlling hillslope erosion

2020 ◽  
Author(s):  
Chengzhong Pan ◽  
Lan Ma
Keyword(s):  
Spatial Distribution ◽  
Soil Erosion ◽  
High Efficiency ◽  
Northern China ◽  
Bare Soil ◽  
Soil Characteristics ◽  
Vegetation Coverage ◽  
Grass Cover ◽  
Run Off ◽  
Set Up

<p>The aim of this study was to investigate how the spatial distribution of grass influenced run-off and erosion from a hillslope with loess and cinnamon soils in the rocky area of Northern China. We set up a trial to test the two soils with different treatments, including bare soil (BS), grass strips on the upper (UGS) and lower (DGS) parts of the slope, grass cover over the entire slope (GS), and a grass carpet on the lower part of the slope (GC), under simulated rainfall conditions. The results showed that the run-off coefficients for the loess and cinnamon soils decreased by between 4% and 20% and by between 2% and 37%, respectively, when covered with grass. Grass spatial distribution had little effect on the run-off, but more effect on erosion than vegetation coverage degree. The most effective location of grass cover for decreasing hillslope erosion was at the foot, and the high efficiency was mainly due to controlling of rill formation and sediment deposition. The soil loss from GS, DGS, and GC on the loess and cinnamon soils was between 77% and 93% less and 55% and 80% less, respectively, compared with the loss from BS. However, the soil characteristics had little effect on soil erosion for well-vegetated slopes. The results highlight the importance of vegetation re-establishment at the foot of hillslope in controlling soil erosion.</p>

scholarly journals Comparison of Tap Water and Normal Saline Iontophoresis in Idiopathic Hyperhidrosis: A Case Report

2014 ◽  
Vol 26 (8) ◽  
pp. 1313-1315
Author(s):  
Zahra Yaghobi ◽  
Sakineh Goljarian ◽  
Ali E. Oskouei
Keyword(s):  
Case Report ◽  
Normal Saline ◽  
Tap Water

CFD Simulation of an Aeroengine Bearing Chamber Using an Enhanced Volume of Fluid (VOF) Method: An Evaluation Using Adaptive Meshing

2014 ◽  
Author(s):  
Alexandre Crouchez-Pillot ◽  
Hervé P. Morvan
Keyword(s):  
Cfd Simulation ◽  
Adaptive Mesh ◽  
Volume Of Fluid ◽  
Vof Method ◽  
Physical Models ◽  
Adaptive Meshing ◽  
Displacement Pump ◽  
Aero Engines ◽  
Set Up ◽  
Cooling And Lubrication

In aero engines, the rotating shafts are supported by a set of bearings, which are enclosed in bearing chambers. Cooling and lubrication oil escapes from the bearings and these chambers are designed to capture and recycle it. A good understanding of the oil behaviour inside bearing chambers is therefore desirable in order to limit the oil volume involved and minimize transmission losses whilst managing the engine core heat in the best possible manner. This study is focused on the simulation of the oil behaviour inside such a chamber and special attention is given to the so-called KIT bearing chamber. The oil phase in the chamber can take different forms e.g. sprays, droplets, thin films or a combination of those. Assuming the oil we want to track remains dominantly as a film and large droplets/filaments, the Volume of Fluid (VOF) method is used in order to track the oil and the oil/air interface in the chamber, hereby investigating the feasibility and merits of such an approach and extending the earlier work carried out by the authors and colleagues. An Enhanced VOF approach coupled with level-set is used here unless stated otherwise. The simulated pump outlet condition, proposed by the University of Nottingham, is also employed in this study, to replicate an engine displacement pump. Since the use of VOF requires a refined mesh in the oil region, an adaptive mesh approach based on the volume of fluid gradient is developed and validated to control the total cell count for some of the cases reported here and limit simulation costs. The Adaptive Mesh Approach (AMA) can allow a better resolution of critical interfaces, better compute the oil break-up (within the limitation of the physical models used) and then track the droplets and filaments. Therefore, not only the CPU time cost might be reduced compared to a fixed mesh approach but significant physical aspects of the problem should be better accounted for. In order to inform the set up and parameters used with this method, and appraise its value for the proposed application, the experimental study of Fabre is used before the approach is applied to the KIT chamber. Good insight is obtained in terms of run time acceleration for such problem when combining the proposed VOF setup with adaptive meshing. Key set up parameters are quantified. The simulations carried out with the proposed set up are proving to be fairly robust and stable. Qualitative (physical) evidence is also encouraging and confirms the value of such an approach to the study of aeroengine bearing chambers.

Comparison of normal saline with tap water for wound irrigation

1998 ◽  
Vol 16 (4) ◽  
pp. 379-381 ◽  
Author(s):  
Ronald Moscati ◽  
James Mayrose ◽  
Lisa Fincher ◽  
Dietrich Jehle
Keyword(s):  
Normal Saline ◽  
Tap Water ◽  
Wound Irrigation

scholarly journals A new thermopile for the measurement of nerve heat-production

1929 ◽  
Vol 105 (735) ◽  
pp. 147-152 ◽  
Keyword(s):  
Heat Production ◽  
Large Mass ◽  
Alcoholic Solution ◽  
Paraffin Wax ◽  
Insulating Material ◽  
Long Time ◽  
In Series ◽  
The Wire ◽  
Gas Flame ◽  
Set Up

The thermopile previously described by Downing, Gerard and Hill (1) for the measurement of the heat-production of nerve had four chief disadvantages : ( a ) it gave a relatively small E. M. F. per 1° C., only about 1800 microvolts altogether, about 4½ per couple; in another of these thermopiles, with a smaller number of couples, 1° C. evoked about 9 microvolts per couple. ( b ) This E. M. F. fell off rather quickly, reaching zero within 45 seconds, owing to rapid heat-conduction, ( c ) The temperature of the thermopile took a very long time to settle down, after placing the nerves upon it, viz., about 4 or 5 hours, ( d ) It was very difficult to construct. Of these, ( a ) was due partly to the small length of each couple exposed to the nerves, and partly to the fact that the wire was in contact on its other side with a relatively large mass of insulating material in the wedge on which it was wound; ( b ) was due partly to the neigh-bourhood of this mass of insulating material, which rapidly cooled the wires and nerve, and partly to the conduction of heat away along the wires to the cold junctions which rather soon warmed up; ( c ) was due to the use of a large mass of insulator, which—being a poor heat conductor—allowed only a very slow equalisation of the temperature differences inevitably set up in the initial handling required in placing the nerve in position; ( d ) was chiefly due to the difficulty of fitting the 3 (or 4) wedges exactly together, without gaps, and of joining their very line wires in series. A first attempt to improve the thermopile in these respects was made as follows. To avoid contact of the wires, in the neighbourhood of the junctions, with a mass of insulating material, the wedges on which the wire was wound were milled out along their narrow ends, as shown at ( a ) in the accompanying figure. The wires passed across the gap, the junctions between silver and constantan being in the middle. In this way about 1½ mm. of wire, i. e., ¾ mm. on either side of the junction, was exposed to nerve on one side without being in contact with anything but air on the other. The wedges were of amber, which will stand baking, and the wires were painted with an alcoholic solution of an artificial resin (“ Elo ”) and baked, the process being repeated several times, until a sufficient layer of insulating varnish had been deposited. The use of this varnish has been described already (2, p. 127). It forms a thin, delicate and almost glass-hard sheet of wires and insulator. After mounting the wedges and finishing the carrier a very thin layer of shellac was painted over the (“Elo”) and any small gaps at the edges were filled up with shellac/working under a Zeiss stereoscopic microscope. Then a mixture of paraffin wax and beeswax was spread very gently and thinly over the surface, and melted on with a minute gas flame. This as described in (2), p. 129, renders the surface waterproof. The ends of the grooves in the wedges were then blocked by the paraffin wax, so that water should not get in, the space between the solid wedge and the wire sheet being thereby rendered air-tight. The mass of insulator employed on the carriage of the thermopile was cut down as much as possible, so as to ensure a more rapid equalisation of temperature.

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