Voltage-temperature charge verification testing of 34 ampere-hour nickel-cadmium cells

This testing was designed to evaluate various voltage-temperature (V-T) charge curves for use in low-Earth-orbit (LEO) applications of nickel-cadmium battery cells. The trends established relating V-T level to utilizable capacity were unexpected. The trends toward lower capacity at higher V-T levels was predominant in this testing. This effect was a function of the V-T level, the temperature, and the cell history. This effect was attributed to changes occurring in the positive plate. The results imply that for some applications, the use of even lower V-T levels may be warranted. The need to limit overcharge, especially in the early phases of missions, is underlined by this test program

Intra-cavitary uterine pathology in women with abnormal uterine bleeding: a prospective study of 1220 women.

OBJECTIVES: Our primary aim was to assess how patients characteristics, bleeding pattern, sonographic endometrial thickness (ET) and additional features at unenhanced ultrasound examination (UTVS) and at fluid instillation sonography (FIS) contribute to the diagnosis of intracavitary uterine pathology in women presenting with abnormal uterine bleeding (AUB). We further aimed to report the prevalence of pathology in women presenting with AUB. METHODS: 1220 consecutive women presenting with AUB underwent UTVS, colour Doppler imaging (CDI) and FIS. Most women (n = 1042) had histological diagnosis. RESULTS: Mean age was 50 years and 37% were postmenopausal. Of 1220 women 54% were normal, polyps were diagnosed in 26%, intracavitary fibroids in 11%, hyperplasia without atypia in 4% and cancer in 3%. All cancers were diagnosed in postmenopausal (7%) or perimenopausal (1%) women. ET had a low predictive value in premenopausal women (LR+ and LR- of 1.34 and 0.74, respectively), while FIS had a LR+ and LR- of 6.20 and 0.24, respectively. After menopause, ET outperformed all patient characteristics for the prediction of endometrial pathology (LR+ and LR- of 3.13 and 0.24). The corresponding LR+ and LR- were 10.85 and 0.71 for CDI and 8.23 and 0.26 for FIS. CONCLUSION: About half of the women presenting to a bleeding clinic will have pathology. In premenopausal women, benign lesions are often the cause of AUB. For the prediction of intracavitary pathology ET is of little value in premenopausal women. CDI and FIS substantially improve the diagnostic accuracy

The impact of communication medium and outcome severity on the effectiveness of social accounts

The present study was designed as a partial test of the model of social accounts by Folger and Cropanzano (1998). Organizational justice researchers have shown that social accounts are effective in reducing negative reactions and displacing blame from the decision-maker following a harmful decision. Using a 2 x 3 completely randomized design, the study examined the effects of outcome severity and media choice on four types of fairness perceptions, medium appropriateness, anger, and turnover intentions. A temporary pay cut scenario was used to manipulate two levels of outcome severity, and the company president provided an explanation of the pay cut using three different media. It was hypothesized that fairness perceptions, anger, and turnover intentions would be most favorable in the low outcome severity conditions and when the social account was delivered through a medium high in media richness. It was also believed that outcome severity and media choice would interact such that the effect of media on the dependent variables would be more pronounced under high outcome severity conditions. One hundred and thirty-two undergraduate students participated in the scenario-based study. Each participant received a brief scenario that stated the president of the company for whom they worked had decided to implement a 10-week pay cut for all employees. A scenario gave detailed information on how the pay cut would affect their weekly net pay

Shape Deformities in Recycled Concrete as a Substitute Aggregate in Concrete

Concrete is a universal material that is used widely across the construction industry. Within a standard concrete mix, a fine aggregate and a coarse aggregate are added to the mix design to help with solidity and compressive strength in the mixture. The admixtures, additives, slump, and mix ratios will differ based on the compressive strength you\u27re trying to attain. This paper directly reflects the results of the differences between shapes in recycled concrete used as a coarse aggregate substitute in concrete mixes. As the construction industry grows, so does outreach towards sustainability and reusing materials anywhere the industry can. Testing concrete re-batched in a new mix is sustainable but seemingly broad. The results found in this paper will shed light on the compressive strengths of re-batched concrete but centralize the focus on the differences in rounded versus jagged pieces. The research found will educate the industry on how applicable recycled jagged concrete used as coarse aggregate could be and help continue more extensive research by industry professionals to allow for potential applications in the real world

Progressive Strain of Sand Due to Cyclic Loading

Progressive axial strain produced by cyclic, triaxial loading conditions was measured on Ottawa sand samples of various relative densities. The theoretical cyclic shearing strain amplitude in each sample was determined using a modified, hyperbolic shearing stress-shearing strain relationship. The data shows a linear log-log correlation between the measured progressive axial strain and the calculated cyclic shearing strain amplitude. The correlation is proposed as a general procedure for predicting progressive strains resulting from general cyclic, triaxial loading conditions

Dynamics and microscopic origin of fast 1.5 μm emission in Er-doped SiO<inf>2</inf> sensitized with Si nanocrystals

We investigate the origin of fast 1.5 μm photoluminescence from Er-doped SiO2 sensitized with silicon nanocrystals, which appears and decays within the first microsecond after a short laser excitation pulse. Time-resolved and temperature-dependent measurements on the 1.5 μm emission from Er-doped and Er-free samples reveal that the major part of this emission is Er related. A possible contribution from other photoluminescence bands, specifically of the defect-related band centered around 1.3 μm, has also been considered. All the results obtained indicate the dominant contribution of Er3+ ions to the fast 1.5 μm emission in the investigated materials. We propose two possible mechanisms behind the fast excitation and quenching of Er3+ 1.5 μm emission, which are both facilitated by Er-related trap centers with ionization energy of EA ∼60 meV. © 2011 American Physical Society