Brittle Temperature of Rubber under Variable Stress

1943 ◽  
Vol 16 (3) ◽  
pp. 609-617
Author(s):  
A. R. Kemp ◽  
F. S. Malm ◽  
G. G. Winspear
Keyword(s):  
Laboratory Test ◽  
High Fracture ◽  
Subzero Temperatures ◽  
Test Conditions ◽  
Made In ◽  
Natural And Synthetic

Abstract 1. The temperature at which natural and synthetic elastomers fracture on bending depends on the rate of application and the magnitude of the stress applied. The slower the rate of bending and the less the angle of bend, the lower will be the temperature of fracture. 2. A study of the stresses under varying types of service at subzero temperatures must be made in order to select intelligently the laboratory test conditions which will best simulate performance in the field. 3. In the case of synthetic elastomers having high fracture temperatures, the addition of certain types of plasticizers serve to correct this difficulty.

scholarly journals A proposal to determine the distribution of lateral forces from loaded recycled plastic drainage kerbs

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Fin O’Flaherty ◽  
Fathi Al-Shawi
Keyword(s):  
Laboratory Test ◽  
Detailed Analysis ◽  
Test Data ◽  
Lateral Force ◽  
Measuring Device ◽  
Test Methodology ◽  
Lateral Forces ◽  
Test Conditions ◽  
Fit For Purpose ◽  
Construction Product

AbstractThis study presents a detailed analysis of the lateral forces generated as a result of vertically applied loads to recycled plastic drainage kerbs. These kerbs are a relatively new addition to road infrastructure projects. When concrete is used to form road drainage kerbs, its deformation is minimum when stressed under heavy axle loads. Although recycled plastic kerbs are more environmentally friendly as a construction product, they are less stiff than concrete and tend to deform more under loading leading to a bursting type, lateral force being applied to the haunch materials, the magnitude of which is unknown. A method is proposed for establishing the distribution of these lateral forces resulting from deformation under laboratory test conditions. A load of 400 kN is applied onto a total of six typical kerbs in the laboratory in accordance with the test standard. The drainage kerbs are surrounded with 150 mm of concrete to the front and rear haunch and underneath as is normal during installation. The lateral forces exerted on the concrete surround as a result of deformation of the plastic kerbs are determined via a strain measuring device. Analysis of the test data allows the magnitude of the lateral forces to the surrounding media to be determined and, thereby, ensuring the haunch materials are not over-stressed as a result. The proposed test methodology and subsequent analysis allows for an important laboratory-based assessment of any typical recycled plastic drainage kerbs to be conducted to ensure they are fit-for-purpose in the field.

scholarly journals Exhaust emissions of particulate matter from light-duty vehicles – an overview and the current situation

2017 ◽  
Vol 171 (4) ◽  
pp. 227-238
Author(s):  
Piotr BIELACZYC ◽  
Andrzej SZCZOTKA ◽  
Joseph WOODBURN
Keyword(s):  
Particulate Matter ◽  
Laboratory Test ◽  
Direct Injection ◽  
Current Situation ◽  
Engine Fuel ◽  
Fuel Type ◽  
Particle Emissions ◽  
Test Conditions ◽  
Light Duty ◽  
Light Duty Vehicles

Emissions of particulate matter associated with the use of light-duty vehicles are an increasingly important topic, with more and more political attention focused on this issue. Now that direct injection Diesel engines feature DPFs, particle emissions from other engine types operating on other fuels are also of great interest. This paper discusses the phenomenon in general, briefly reviews worldwide legislation and emissions limits and presents the results of a laboratory test programme measuring the particle emissions from a range of vehicles. The experimental programme showed that the engine/fuel type has a greater impact on particle emissions than the test conditions.

On the Lubrication Mechanism of SbSbS4

1982 ◽  
Vol 40 ◽  
pp. 530-531
Author(s):  
J. S. Harris ◽  
L.K. Ives ◽  
M. B. Peterson
Keyword(s):  
Laboratory Test ◽  
Friction And Wear ◽  
Solid Lubricant ◽  
Wear Behavior ◽  
Powder Form ◽  
Extreme Pressure ◽  
Lubrication Mechanism ◽  
Friction And Wear Behavior ◽  
Test Conditions ◽  
Wear Tests

Recent investigations have shown that SbSbS4 is a promising solid lubricant. It exhibits outstanding extreme pressure (EP) performance, and good antiwear behavior under laboratory test conditions. An investigation was undertaken to identify the mechanism by which SbSbS4 functioned when used as a lubricant in the dry powder form and as an additive to oils and greases. Friction and wear behavior of SbSbS^ was investigated using several different wear tests carried out in air at temperatures ranging from 20°C to 500°C.

scholarly journals Experimental Evaluation of Oxide Nanoparticles as Friction and Wear Improvement Additives in Motor Oil

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Nicholaos G. Demas ◽  
Robert A. Erck ◽  
Cinta Lorenzo-Martin ◽  
Oyelayo O. Ajayi ◽  
George R. Fenske
Keyword(s):  
Laboratory Test ◽  
Coefficient Of Friction ◽  
Friction And Wear ◽  
Oxide Nanoparticles ◽  
Test Machine ◽  
Motor Oil ◽  
Test Configuration ◽  
Test Conditions ◽  
Contact Configuration ◽  
The Coefficient Of Friction

The effect of two nanoparticle oxides on friction and wear was studied under laboratory test conditions using a reciprocating test machine and two test configurations. The addition of these nanoparticles in base stock oil under certain conditions reduced the coefficient of friction and improved wear, but that depended on the test configuration. Examination of the rubbed surfaces showed the pronounced formation of a tribofilm in some cases, while polishing on the surface was also observed in other cases. Contact configuration is important when oxide nanoparticles are being evaluated and the conclusions about their efficacy can be vastly different.

scholarly journals Performance of Photovoltaic Modules of Different Solar Cells

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Ankita Gaur ◽  
G. N. Tiwari
Keyword(s):  
Solar Cells ◽  
Minimum Cost ◽  
Electrical Energy ◽  
Energy Generation ◽  
Standard Test ◽  
Photovoltaic Modules ◽  
Test Conditions ◽  
Pv Modules ◽  
Electrical Energy Generation ◽  
Made In

In this paper, an attempt of performance evaluation of semitransparent and opaque photovoltaic (PV) modules of different generation solar cells, having the maximum efficiencies reported in the literature at standard test conditions (STC), has been carried out particularly for the months of January and June. The outdoor performance is also evaluated for the commercially available semitransparent and opaque PV modules. Annual electrical energy, capitalized cost, annualized uniform cost (unacost), and cost per unit electrical energy for both types of solar modules, namely, semitransparent and opaque have also been computed along with their characteristics curves. Semitransparent PV modules have shown higher efficiencies compared to the opaque ones. Calculations show that for the PV modules made in laboratory, CdTe exhibits the maximum annual electrical energy generation resulting into minimum cost per unit electrical energy, whereas a-Si/nc-Si possesses the maximum annual electrical energy generation giving minimum cost per unit electrical energy when commercially available solar modules are concerned. CIGS has shown the lowest capitalized cost over all other PV technologies.

Effects of laboratory test conditions on the toxicity of silver to aquatic organisms

1998 ◽  
Vol 17 (4) ◽  
pp. 572-578 ◽  
Author(s):  
Russell J. Erickson ◽  
Larry T. Brooke ◽  
Michael D. Kahl ◽  
Fred Vende Venter ◽  
Sandra L. Harting ◽  
...  
Keyword(s):  
Laboratory Test ◽  
Aquatic Organisms ◽  
Test Conditions

scholarly journals Segmental volume changes that occur in nonhuman primates during short term head up (HUT) and head down (HDT) tilt

2020 ◽  
Vol 11 (1) ◽  
pp. 12-18
Author(s):  
Leslie David Montgomery ◽  
Clarence Oloff
Keyword(s):  
Rhesus Monkeys ◽  
Nonhuman Primates ◽  
Impedance Plethysmography ◽  
Squirrel Monkeys ◽  
Orthostatic Test ◽  
Volume Changes ◽  
Short Term ◽  
Test Conditions ◽  
Postural Changes ◽  
Made In

AbstractNonhuman primates are often used in biomedical research and to investigate physiologic processes that occur in man. Impedance plethysmography was used to measure calf, thigh, pelvic, abdominal, and thoracic volume changes in ten Rhesus and eight squirrel monkeys during five-minute exposures to HUT and HDT at angles of 5, 10, and 20 degrees. Calf, rump and tail measurements were made in three squirrel monkeys at 10 and 20 degrees of HUT and HDT. Fluid volume changes in all segments of the Rhesus monkeys were found to change during HUT an HDT in direct relation to the angle of tilt used. However, the volume changes that occurred in the squirrel monkeys were found to be quite different. Their calf, thigh, and pelvic segments lost volume during both HUT and HDT while their abdominal and thoracic segments responded similarly to those of the Rhesus monkeys. These results and those of the calf/tail measurements of the squirrel monkeys suggest that they may utilize their tails as a compensatory reservoir during postural changes and therefore, may not be an appropriate animal model for man under some orthostatic test conditions.

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