Pull-Through Adhesion Test

1956 ◽  
Vol 29 (3) ◽  
pp. 1066-1081
Author(s):  
J. O. Wood
Keyword(s):  
High Temperature ◽  
Temperature Increase ◽  
Fold Increase ◽  
Absolute Temperature ◽  
Appreciable Effect ◽  
Adhesion Test ◽  
Cent Increase ◽  
Series Of Experiments ◽  
Pull Through ◽  
Cord Length

Abstract A modified form of the pull-through test is described, followed by a series of experiments, the first three of which demonstrate the precision of the method. Further experiments assess the effect of various factors on the pull-through force. It is found that specimen age has little effect. The tension applied to the cord during construction also produces a small but appreciable effect, amounting to a decrease of 1.3 per cent for a two-fold increase of the tension, but a greater effect, amounting to a 7 per cent increase of the pull-through force, is obtained when the rate of loading is doubled. The pull-through force is also shown to depend on the shape of the mounting device. The twist in a rayon cord does not give a significant effect, though the variability exhibited by the conventionally dipped cord is high. Temperature increase during test reduces the pull-through force; linear plots of the logarithm of the pull-through force against the reciprocal of the absolute temperature are obtained. The cord length embedded in the rubber is shown to bear a hyberbolic relationship to the pull-through force, confirming the theoretical relationship obtained analytically. Finally the pull-through test is considered in terms of the product.

Latch-Up Induced Slit Voiding in Aluminum Metal Lines

1999 ◽  
Author(s):  
Chunyu Zhang ◽  
Lakshmi Vedula ◽  
Shekhar Khandekar
Keyword(s):  
High Temperature ◽  
Line Width ◽  
Fold Increase ◽  
Metal Line ◽  
Operating Life ◽  
Mixed Signal ◽  
Aluminum Metal ◽  
Temperature Operating ◽  
Latch Up

Abstract Latch-up induced during High Temperature Operating Life (HTOL) test of a mixed signal device fabricated with 1.0 μm CMOS, double poly, double metal process caused failures due to an open in aluminum metal line. Metal lines revealed wedge voids of about 50% of the line width. Triggering of latch up mechanism during the HTOL test resulted in a several fold increase of current flowing through the ground metal line. This increase in current resulted in the growth of the wedge voids leading to failures due to open metal lines.

scholarly journals On the relative attractions of sulphuric acid for water, under particular circumstances: with suggestion of means of improving the ordinary process of manufacturing sulphuric acid

1843 ◽  
Vol 4 ◽  
pp. 81-82
Keyword(s):  
High Temperature ◽  
Specific Gravity ◽  
Sulphuric Acid ◽  
Conclusive Evidence ◽  
Dew Point ◽  
Chemical Affinity ◽  
Dilute Acid ◽  
Atmospheric Air ◽  
Open Atmosphere ◽  
Series Of Experiments

The object of the inquiry detailed in the present paper is to determine at what degree of concentration the affinity of sulphuric acid for aqueous vapour is equal to that of anhydrous space for the same vapour at given temperatures. It has long been known that concentrated sulphuric acid abstracts moisture from the atmosphere, but the amount and the rate of this absorption have never been ascertained with accuracy; and consequently, in applying this acid to purposes of exsiccation, the experimenter has often been at a loss to know whether the acid was sufficiently strong to render the space in which it was confined perfectly anhydrous. By placing portions of the acid, previously weighed, and diluted with known quantities of water, under the receiver of an air-pump, with equal portions of concentrated acid, of the specific gravity 1·8428, in similar dishes, the author ascertained that the dilute acid could be concentrated to the specific gravity 1·814, at a temperature varying from 65° to 57°: whence he concludes that acid of such strength is capable of drying a vacuum when the temperature does not exceed 57°. By making similar experiments in air, the author compared together the weights lost by ten grains of dilute sulphuric acid of the specific gravity 1·135, at three different periods of the day for six days, taking note of the dew-point and the temperature; and infers that when the affinity of space for vapour, or the evaporating force, is equal to 0·15 of an inch of mercury, it is just able to balance the affinity for water of sulphuric acid of the specific gravity 1·249. The author next instituted a series of experiments to ascertain whether the evaporation of water from dilute sulphuric acid is capable of being carried on to the same extent in air as in vacuo, and found that the evaporating force of air exerted upon such acid is less than that of a vacuum at the same temperature. He observes that his experiments offer conclusive evidence that the evaporation of water is not owing to the existence of a chemical affinity between the vapour of the liquid and atmospheric air; but thinks that they favour the notion that the obstruction to this process in the open atmosphere is rather owing to the pressure than to the inertiæ of the particles of air. He is also of opinion that improvements will hereafter arise from this inquiry with regard to the economical management of the process of manufacturing sulphuric acid, which process would be greatly expedited by the regulated admission of steam into the condensing chambers kept at a constant high temperature.

Further observations of enhanced lines

1897 ◽  
Vol 61 (369-377) ◽  
pp. 441-444 ◽  
Keyword(s):  
High Temperature ◽  
Solar Chromosphere ◽  
Stellar Spectra ◽  
Series Of Experiments

In a recent paper I gave an account of a series of experiments having for their object the determination of the lines which were enhanced in the spectra of iron, magnesium, and calcium, on passing from the arc to a high temperature spark, and I pointed out the presence of these lines in the spectra of the hotter stars and in the solar chromosphere. The spectra of the following additional elements have since been investigated in a similar manner, and the enhanced lines have been tabulated and compared with chromospheric and stellar spectra.

scholarly journals Technical Variations in Koelle's Histochemical Method for Demonstrating Cholinesterase Activity

1963 ◽  
Vol s3-104 (65) ◽  
pp. 89-100
Author(s):  
N. T. NAIK
Keyword(s):  
Cold Storage ◽  
Cholinesterase Activity ◽  
Enzyme Reaction ◽  
Progressive Increase ◽  
Histochemical Method ◽  
Appreciable Effect ◽  
Selective Inhibitors ◽  
Ph Values ◽  
Contrast Microscopy ◽  
Series Of Experiments

Koelle's histochemical method for demonstrating cholinesterase activity and the literature on its subsequent modifications have been reviewed. Experiments were carried out on the effect on the cholinesterase reaction of formaldehyde fixation, cold storage of tissues, pH of incubation solution, and progressive increase of incubation time. A series of experiments was also carried out in testing the specificity of substrates and selective inhibitors used in the Koelle method. Enzyme reaction was visualized by the ammonium sulphide method. As a result of these experiments the following technical desiderata have been established: 1. Fixation of tissues for 3 h in neutral formaldehyde solution at 4° C preserved the morphology of the tissues without appreciably affecting the histochemical results. Fixation for more than 6 h produced definitive inhibition of cholinesterases, especially AChE, in most tissues. 2. Periods of up to 24 h of cold storage before fixation had no appreciable effect on the cholinesterase reaction. 3. Incubation at pH values between 5.0 and 6.0 produced neither significant diffusion artifacts nor loss of enzyme activity. Below pH 5 the AChE reaction was affected to a varying extent according to the tissues used. 4. B.W. 284 at a concentration of 5 x 10-5 M and ethopropazine hydrochloride at a concentration of 1 x 10-4 M were found to be suitable selective inhibitors for AChE and ChE respectively. 5. Visualization of results by means of ammonium sulphide method was found to be preferable to phase-contrast microscopy.

Responding to Bioterror Concerns by Increasing Milk Pasteurization Temperature Would Increase Estimated Annual Deaths from Listeriosis

2014 ◽  
Vol 77 (5) ◽  
pp. 696-705 ◽  
Author(s):  
MATTHEW J. STASIEWICZ ◽  
NICOLE MARTIN ◽  
SHELLEY LAUE ◽  
YRJO T. GRÖHN ◽  
KATHRYN J. BOOR ◽  
...  
Keyword(s):  
Public Health ◽  
High Temperature ◽  
Time Lag ◽  
Fold Increase ◽  
Quantitative Microbial Risk Assessment ◽  
The Public ◽  
High Temperature Short Time ◽  
Increased Risk ◽  
Short Time ◽  
Fluid Milk

In a 2005 analysis of a potential bioterror attack on the food supply involving a botulinum toxin release into the milk supply, the authors recommended adopting a toxin inactivation step during milk processing. In response, some dairy processors increased the times and temperatures of pasteurization well above the legal minimum for high temperature, short time pasteurization (72°C for 15 s), with unknown implications for public health. The present study was conducted to determine whether an increase in high temperature, short time pasteurization temperature would affect the growth of Listeria monocytogenes, a potentially lethal foodborne pathogen normally eliminated with proper pasteurization but of concern when milk is contaminated postpasteurization. L. monocytogenes growth during refrigerated storage was higher in milk pasteurized at 82°C than in milk pasteurized at 72°C. Specifically, the time lag before exponential growth was decreased and the maximum population density was increased. The public health impact of this change in pasteurization was evaluated using a quantitative microbial risk assessment of deaths from listeriosis attributable to consumption of pasteurized fluid milk that was contaminated postprocessing. Conservative estimates of the effect of pasteurizing all fluid milk at 82°C rather than 72°C are that annual listeriosis deaths from consumption of this milk would increase from 18 to 670, a 38-fold increase (8.7- to 96-fold increase, 5th and 95th percentiles). These results exemplify a situation in which response to a rare bioterror threat may have the unintended consequence of putting the public at increased risk of a known, yet severe harm and illustrate the need for a paradigm shift toward multioutcome risk benefit analyses when proposing changes to established food safety practices.

Catalytic Pyrolysis of Shenhua Coal to Prepare Fuel Gases Using Metallic Oxide Supported Catalysts

2012 ◽  
Vol 443-444 ◽  
pp. 1084-1090
Author(s):  
Zhan Ying Guo ◽  
Rong Ran ◽  
Xin Qian Shu ◽  
Ying Ying Yuan ◽  
Yue Zhang ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
High Temperature ◽  
Catalytic Pyrolysis ◽  
Supported Catalysts ◽  
Positive Influence ◽  
Metallic Oxide ◽  
Medium Temperature ◽  
Strong Adsorption ◽  
Series Of Experiments ◽  
The Individual

In order to study the catalytic activity in the preparation of fuel gases from catalytic pyrolysis of coal, the author selects NixOy/γ-Al2O3、CrxOy/γ-Al2O3，AgxOy/γ-Al2O3 and CoxOy/γ-Al2O3, respectively as the metal oxide supported catalysts from the previous experiment’s results. These catalysts have been added to Shenhua coal for a series of experiments. After these experiments, GC (gas chromatography) has been used for the analysis on the yield changes of CO and CH4 which result from the experiments. The results show that all of these catalysts have a positive influence on the yield of CO and CH4. As to the yield of CO, catalytic activity of CrxOy/γ-Al2O3 represents the most prominent performance at medium temperature period and CoxOy/γ-Al2O3 represents the same performance at high temperature period, while NixOy/γ-Al2O3, in which a great number of aluminum acid nickel spinels are reduced into metallic Ni at high temperature period, which results in different catalytic activity center from raw metallic Ni reduced from NiO. Consequently, the former reduced Ni shows outstanding catalytic activity. As to the yield of CH4, four catalysts mentioned above represent either the similar catalytic activity with CO or the individual characteristic —on one hand ,due to the strong adsorption of AgO and CrO3, CH4 gas is changed into H2 via pyrolysis at medium temperature as the yield of CH4 slumps ,on the other hand, due to an enormous amount of H2 production ,there is a drastically chemical reaction between H2 and these catalysts at high temperature, in which the yield of CH4 upswings toward the maximum amount greatly at the same time. Therefore, CrxOy/γ-Al2O3, AgxOy/γ-Al2O3 and CoxOy/γ-Al2O3 are more efficient at medium temperature and high temperature respectively. However, NixOy/γ-Al2O3 demonstrates the positive influence only from 800°Con. All of these results depend on the essence of catalysts to some extent. The study would have some theoretical guidance about increasing the utilization of coal and about industrial application of fuel gases generated from catalytic pyrolysis of coal.

Stress Analysis of Cord Adhesion Tests — A Route to Improved Tests

1981 ◽  
Vol 54 (4) ◽  
pp. 835-856 ◽  
Author(s):  
R. A. Ridha ◽  
J. F. Roach ◽  
D. E. Erickson ◽  
T. F. Reed
Keyword(s):  
Stress Analysis ◽  
Small Strain ◽  
Good Alternative ◽  
Strength Properties ◽  
Square Root ◽  
Rubber Compound ◽  
Adhesion Test ◽  
Pullout Force ◽  
Pull Through ◽  
Maximum Stresses

Abstract Stress fields were calculated in tire cord adhesion test specimens as a route to the development of improved wire adhesion tests. The calculated stresses were analyzed in order to predict the location of initiation of debonding and to assess the dependence of the cord pullout force on the modulus of the rubber compound. The computational results were validated by experiments on a variety of cord/rubber samples. Conclusions drawn from this study are as follows: The analyzed pull-through test for adhesion of steel wires has a serious drawback. Its major deficiency lies in the presence of a slot under the rubber block specimen. Maximum stresses are consistently higher at the slot edges than at the cord/rubber interface. This is responsible for: (a) initiation of failure at the slot edges rather than at the cord/rubber interface, (b) considerable rubber coverage, and (c) dependence of the cord pullout force on the strength properties of rubber. The test is more likely to test the strength of the rubber compound than it is to test the strength of adhesion. The TCAT test represents a significant improvement over the pull-through test with regard to the location of failure. Stresses at the cord/rubber interface are higher than elsewhere within the sample. Stresses along the cord show a high peak at the cord's embedded end. This highly localized peak initiates debonding at the embedded end and yields good reproducibility (failure is very unlikely to initiate elsewhere). Experiments on the TCAT specimen show a reproducibility of within 4.2%. Maximum stresses in the TCAT specimen vary with approximately the square root of the rubber modulus. Thus, while the TCAT may be an excellent choice for wire studies involving a single control compound, it may be limited when used in compounding studies and other tire applications which involve changes in the rubber properties. In such studies, the dependence on rubber modulus is viewed as a limitation of TCAT because: (a) unintentional changes in the rubber modulus will affect the cord pullout force and can lead to erroneous assessment of the adhesive strength, and (b) intentional changes in the rubber modulus cannot be simply factored out by a square root rule. Our experiments show that the exponent of the rubber modulus depends on how the modulus change is achieved. There are also many definitions of the modulus and several techniques for determining its value. Experiments on the SWAT test show a pullout force proportional to a lower exponent of the rubber modulus than the exponent in the TCAT test. Reproducibility is at 5.6%, i.e., somewhat poorer than the TCAT. The width of the sample, and the presence of cord reinforcements within that width (in addition to the cords being tested), are expected to change the stress distribution along the cords from the distribution in the TCAT test. The 9.5 mm × 9.5 mm steel-backed specimen represents a good alternative for adhesion tests in compounding studies and tire applications. Although its reproducibility is not as good as those of the TCAT and SWAT tests, its independence from the rubber properties and its ease of sample preparation make it a good alternative. Finite element stress analysis of adhesion tests can provide useful information for assessing alternative tests and developing improved tests. Although total cord pullout normally takes place after large deformations in the rubber, simplified, small strain material models can provide a good indication of the behavior of adhesion test specimens.

The effect of abrupt temperature increase on growth and phosphorus fractions of Pisum sativum

1969 ◽  
Vol 47 (7) ◽  
pp. 1199-1203 ◽  
Author(s):  
J. Rowell M. Potts ◽  
Douglas P. Ormrod
Keyword(s):  
High Temperature ◽  
Temperature Increase ◽  
Elevated Temperatures ◽  
Inorganic Phosphorus ◽  
Phosphorus Fractions ◽  
Internode Elongation ◽  
High Temperature Exposure ◽  
Controlled Environments ◽  
Temperature Exposure ◽  
Node Formation

Pea plants were grown in controlled environments at 25/15 C day/night temperatures and transferred abruptly to each of three higher temperatures, 32/22, 35/25, and 38/28 C, to determine the effects on growth and development and on phosphorus fractions. Samples were taken for analysis on a logarithmic high-temperature exposure time scale. Rate of node formation increased sharply during the first 24 hours of exposure to the elevated temperatures and then declined to a rate which was somewhat greater than that of 25/15 C plants. Rate of internode elongation was initially stimulated and then slowed slightly during continued high temperature exposure. Inorganic phosphorus declined slightly within 10 minutes of temperature increase but increased to about three times the original level by 6 days. Organic, lipid, and nucleic acid and protein phosphorus were not appreciably affected by the temperature change.

scholarly journals Estresse Térmico – os efeitos do calor sobre o desempenho físico

2018 ◽  
Vol 87 (4) ◽  
Author(s):  
Danielli Braga de Mello
Keyword(s):  
Thermal Stress ◽  
High Temperature ◽  
Physical Exercise ◽  
Physical Performance ◽  
Temperature Increase ◽  
Extreme Heat ◽  
Global Temperature ◽  
Prevention Strategies ◽  
Central Temperature ◽  
Outdoor Activities

Introdução: A temperatura global vem aumentando ao longo dos anos. Paralelo a isto, vem aumentando cada vez mais o número de praticantes em atividades outdoor. Sendo assim, torna-se essencial entender a fisiologia da termorregulação e os mecanismos de aumento datemperatura central para prever o risco de estresse térmico em ambientes quentes.Objetivo: O objetivo deste comentário foi refletir sobre os efeitos do calor na saúde e no desempenho físico, bem como apresentar as estratégias de reconhecimento e prevenção das doenças do calor.Conclusão: O ambiente extremo do calor influencia a saúde e o desempenho e a melhor forma de evitar os agravos à saúde e as doenças associadas à prática de exercício físico em ambientes de altas temperaturas climáticas é utilizar as estratégias de reconhecimento e prevenção.Thermal Stress - The Effects of Heat on Physical Performance Introduction: Global temperature has been increasing over the years. Parallel to this, the number of practitioners in outdoor activities has been increasing. Therefore, it is essential to understand the physiology of thermoregulation and the mechanisms of central temperature increase to predict the risk of thermal stress in hot environments.Objective: The purpose of this review was to reflect on the effects of heat on health and physical performance, as well as to present strategies for the recognition and prevention of heat illness.Conclusion: The extreme heat environment influences health and physical performance and the best way to avoid health problems and diseases associated with physical exercise in high temperature environments is to use recognition and prevention strategies.

Characterization of Nanoscale Clusters in Ods Iron-Based Alloys

2001 ◽  
Vol 7 (S2) ◽  
pp. 550-551
Author(s):  
E.A. Kenik ◽  
D. Hoelzer ◽  
P.J. Maziasz ◽  
M.K. Miller
Keyword(s):  
High Temperature ◽  
Dislocation Density ◽  
Oxide Dispersion Strengthened ◽  
Fold Increase ◽  
Ferritic Alloys ◽  
High Temperature Mechanical Properties ◽  
Dislocation Pinning ◽  
Iron Based ◽  
Nanoscale Clusters

The high temperature application of iron-based ferritic alloys is limited by their rapid decrease of yield strength at temperatures approaching 1000°C. It has been shown that mechanical-alloying (MA) to produce oxide dispersion-strengthened (ODS) ferritic alloys improves their high temperature mechanical properties. Prior characterization of such materials has shown that in certain as-processed alloys the original yttria oxide particles are replaced by nanoscale (2-5 nm diameter) clusters containing Ti, Y and O. As a result of the high density of these fine clusters, dislocation pinning produced a ∼10-fold increase in dislocation density relative to similar ODS materials not exhibiting the nanoscale clustering. The improved creep resistance of the clustered material was attributed both to the higher dislocation density, additional dislocation pinning and resistance to recovery during creep. The current work examines clustering in a related alloy, as well as the effects of high temperature creep on the stability of such clusters.

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