... Title : A Study of Hydrogen Sulfide Accelerated Stress-Corrosion Cracking in D6ac Steel. Descriptive Note : Memorandum rept.,. ...

The use of electrical impedance plethysmography of the head, or rheoencephalography (REG), has been demonstrated in a high acceleration stress environment on human volunteer subjects. Acceleration stress was primarily applied in the head-to-foot direction...

... Second, a stress analysis was conducted to determine the influence of the centrifugal forces on the spokes and the rims of accelerator. ...

A convenience sample based on availability of tibial stress fracture cases at local Sports Medicine Clinics was selected. The study was designed to determine if electric field stimulation accelerates the healing of tibial stress fracture and whether there...

... of passengers against the stresses of high accelerations and radiations in space, psychological studies, biophysics research, and astronautics. ...

... Title : Synchronous External Pulsation for Improved Tolerance to Acceleration Stress: Model Studies and Preliminary Experiments. ...

test was performed to support a risk assessment of a "work-around" necessitated ..... at the start of the test as the control bondwires, ...

In this report, the raw data obtained from accelerated stress-rupture studies of Kevlar 49/epoxy strand specimens is presented.

Synchronized external pulsation is proposed as a method to improve tolerance to acceleration stress. This technique uses a modified anti-G suit which is pressurized and depressurized synchronously with the heart cycle. The feasibility of the procedure has...

The mechanical behavior of M30 propellant subjected to an acceleration greater than 10,000 g has been studied in an ultracentrifuge. Deformation of the propellant is measured as a function of maximum applied stress. Above an acceleration threshold, recove...

This study was composed of three parts: a post cure study to optimize final properties of an ethylene-propylene-diene (EPDM) formulation, an accelerated aging study to compare the stress relaxation behavior of a butyl and an EPDM elastomer under compressi...

... Descriptors : *CANTILEVER BEAMS, *BENDING STRESS, *SHEAR STRESSES, DEFLECTION, TRANSVERSE, EQUATIONS, ACCELERATION ...

This document describes a system designed to study the feasibility of augmenting tolerance to acceleration stress using external pressure pulsations synchronized to the electrocardiogram. The system, known as synchronized pulsating anti-gravity suit, cons...

The development of high performance fighter-attack aircraft has created a need for new techniques and methods to study the effects of acceleration stress on the cardiovascular system. Instrumentation methods were developed in the rhesus monkey (Macaca mul...

The staff of the Combined Stress Branch has completed the integration of a system to allow quantitative measurement of perceived attitude while under sustained acceleration. Equipment involved included the computer control system of the Dynamic Environmen...

In the full-scale fatigue testing of the Concorde there is a need to accumulate damage at a higher rate than in service in order to meet certification requirements. One contribution to the more rapid testing of the Concorde comes from accelerating the rat...

... acceleration on the airplane back to the one g level following a ... for a particular aircraft. ... the material properties is greater at lower stress levels, which ...

could lead to fatigue failure of the bond material. ... this paper, separate testing was performed and concluded ... Aluminum could be found, the analysis used the ...

... Descriptors : *ELECTRON ACCELERATORS, *LINEAR ACCELERATORS, *MICROWAVES, *TRAVELING WAVE ELECTRON ACCELERATORS ...

Available data relating duration of acceleration stress to blood gas exchange status is limited. Furthermore, studies focusing on pulmonary gas exchange during acceleration stress when abdominal restriction is imposed have yielded conflicting results. To ...

The temperature rise and induced stress due to Ohmic heating in the vicinity of microcracks on the walls of high-gradient accelerating structures are considered. The temperature rise and induced stress depend on the orientation of the crack with respect to the rf magnetic field, the shape of the crack, and the power and duration of the ...

The exfoliation corrosion and stress corrosion cracking (SCC) behavior of damage tolerant sheet and plate materials of aluminum-lithium based alloys in underaged tempers was studied performing different accelerated tests. The EXCO test (ASTM G34) produced...

... VARIATIONS IN ABSOLUTE VISUAL THRESHOLDS CC DURING ACCELERATION STRESS ... DURING ACCELERATION STRESS William J. White ...

The results of accelerated stress testing of four different types of silicon terrestrial solar cells

Test procedures for accelerated stress-corrosion testing of high-strength aluminum alloys faster and

This lesson plan provides activities for learning about acceleration, and differentiating between vector and scaler quantities. The distinction between velocity and acceleration is stressed.

The electromagnetic acceleration of projectiles with an ablator using sequential Z pinches in a cylindrical electrode array is studied analytically under an assumption that every stage of the Z pinches, except the first one, is triggered automatically by the Z pinch following after the projectile. The effect of ablation on the ...

... _ i_ i NADC-MR-7015 2 July 1970 Activation Energies of Acceleration and Hypoxia Stress ... Activation Energies of Acceleration and Hypoxia Stress ...

A study has been carried out in order to develop methods for determining failure mechanisms of IMPATT diodes and for accelerating them in a controlled way. Interactions between the constituents of the contact metallizations leading to catastrophic thermal runaways are shown to be the principal mechanism of degradation and failure of IMPATT diodes. It is ...

For an accelerated life test, let V sub 1,...,V sub k denote k fixed accelerated stresses and let V sub 0 be the normal stress. It is assumed that the probability distributions corresponding to the accelerated stresses differ from the nonaccelerated life ...

The maximum Van Mises stress and stress direction are of interest far analyzing launch accelerations

... The stress levels of applied stimuli must be as harsh as ... Application of environmental stresses will accelerate the latent (or undetected) defects to ...

Cyclic deformation and fatigue fracture behavior of Al alloy 6061 were studied over an extensive range of positive mean stress. In the regime of low cyclic stress amplitude, both secondary stage creep rate and fracture process are retarded by decreasing mean stress, but they are accelerated If ...

This paper describes a methodology for assessing critical stress ranges arising in automotive plain bearings during engine operations. An industry-produced and run simulation program provides information on oil film pressure and overall bearing deformation during accelerated performance tests. This code performs an elasto-hydrodynamic lubrication analysis ...

... PARTICLE ACCELERATORS, *TRITIUM, *PRODUCTION ENGINEERING, FEASIBILITY STUDIES, PARTICLE ACCELERATOR TARGETS, HELIUM ...

Pine Island Glacier, Antarctica, has been undergoing several related changes for at least two decades; these include acceleration, thinning and grounding line retreat. During the first major ground-based study between 2006 and 2008, GPS receivers were used to monitor ice flow from 55 km to 171 km inland, along the central flowline. At four sites both ...

Pine Island Glacier, Antarctica, has been undergoing several related changes for at least two decades; these include acceleration, thinning and grounding line retreat. During the first major ground-based study between 2006 and 2008, GPS receivers were used to monitor ice flow from 55 km to 171 km inland, along the central flowline. At four sites both ...

accelerate electrons? Parameter dependence of electron acceleration at shocks ? ... al., 2005). Many studies on ions, but how about electron acceleration ? ...

This study was composed of three parts: a post cure study to optimize final properties of an ethylene-propylene-diene (EPDM) formulation, an accelerated aging study to compare the stress relaxation behavior of a butyl and an EPDM elastomer under compression, and a cursory evaluation of a new 70 ...

Stress-corrosion cracking data for various tempers of D6ac steel is presented. The data pertain to aqueous and to gaseous hydrogen sulfide environments. The data show that the effect of increased tempering temperature increase the stress intensity thresho...

The long-term tensile strength retention of Kevlar 49 (aramid fiber)/epoxy composite under sustained loading at 56.4 percent of the ultimate fiber tensile strength (3400 MPa) was studied to evaluate the lifetime to failure of the composite under the same load level. To obtain data in a conveniently short time, elevated temperature was used according to an ...

The critical stress for initiation of stress corrosion cracking (SCC) of a duplex stainless steel (DSS) in a sour environment was investigated using three stress application techniques: constant-strain, constant-load, and slow strain rate testing (SSRT). The critical stresses for SCC initiation as determined by ...

Results obtained during the reporting period include the identification of need for a short-interval solar cell tester and the definition of such a tester, the acquisition of significant amounts of data on stress-tested cells of two types from most of the planned stress tests, and progress in understanding the types of measurements and methods of ...

The compilation contains 215 selected references pertaining to behavioral and biomedical research involving human subjects. The references are organized under three topics: (1) Physiological Studies, including acceleration stress tolerance and physiologic...

Cardiovascular studies indicated the importance of beat-to-beat regulation of heart rate via the aortic nerve, the importance of the pericardium in minimizing stresses, and following positive acceleration in unprotected subjects acute cardiopulmonary cong...

A slow rotation room in a laboratory environment provides an excellent instrument for the study of motion sickness because the experimenter can control not only the stressful Coriolis accelerations, but also other important procedural and environmental va...

Recent studies of the effect of various types of stress on the phospholipid composition of blood plasma and tissues showed that whole body X-ray irradiation, or acceleration of rats up to 20g was regularly accompanied by a significant increase of one part...

Liquid ventilation of the lungs to diminish acceleration/deceleration stresses was studied. Since ions permeating the alveolo capillary barrier might induce serious electrolyte disturbances in the serum, the permeability of the alveolo-capillary membrane ...

Myocardial biochemical systems which are sensitive to hypoxic and ischemic insult were studied to determine the possible etiology of ventricular endocardial hemorrhage in miniature swine following +G(z) stress. Unanesthetized animals were subjected to a s...

In the present study we are developing an experimental fracture material property test method specific to dynamic fragmentation. Spherical test samples of the metals of interest are subjected to controlled impulsive stress loads by acceleration to high ve...

A program to develop accelerator dipoles with significantly enhanced performance, into the 8-tesla range is described. Analytical design studies, based on idealized configurations, have been done to trace the dependence of stresses within the coil and ove...

A review of the literature is presented with the objectives of identifying relationships between various accelerated stress corrosion testing techniques, and for determining the combination of test methods best suited to selection and design of high stren...

One of the methods proposed to prevent the potential deconditioning effect of prolonged space flight is the use of a short-radius centrifuge to provide periodic, prolonged, low-intensity, acceleration stress. To exclude anesthesia effects and to evaluate ...

During salt dissolution, waste compositions may reach temperature and nitrate concentrations not covered by the present technical standards. Stress corrosion cracking (SCC) is a possible degradation mechanism of waste tank steels. Accelerated electrochemi...

Although acute stress accelerates colonic transit, the effect of chronic stress on colonic transit remains unclear. In this study, rats received repeated restraint stress (chronic homotypic stress) or various types of stress (chronic heterotypic ...

... Title : Use of Accelerated Intergranular Corrosion Tests and Pitting Corrosion Tests to Detect Sensitization and Susceptibility to Intergranular Stress ...

... Descriptors : *ACCELERATION, *FINITE ELEMENT ANALYSIS, *SHELTERS, *DYNAMIC LOADS, STRESSES, MATHEMATICAL MODELS, MASS ...

... Accession Number : AD0709569. Title : ACTIVATION ENERGIES OF ACCELERATION AND HYPOXIA STRESS. Descriptive Note : Phase rept. ...