477 research outputs found

    Methods for predicting properties and tailoring salt solutions for industrial processes

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    An algorithm developed at Oak Ridge National Laboratory accurately and quickly predicts thermodynamic properties of concentrated aqueous salt solutions. This algorithm is much simpler and much faster than other modeling schemes and is unique because it can predict solution behavior at very high concentrations and under varying conditions. Typical industrial applications of this algorithm would be in manufacture of inorganic chemicals by crystallization, thermal storage, refrigeration and cooling, extraction of metals, emissions controls, etc

    Mechanical Performance of Cementitious Composites by MWCNTs Addition for Structural Applications

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    This paper presents the investigation on the behaviour of a prism reinforced with multi walled carbon nanotubes (MWCNTs) to study mainly the strength and durability aspects for structural applications. Prisms were made by varying the MWCNT content from 0.1 to 0.5% by weight of cement. Ultrasonic energy was employed to disperse carbon nano tubes (CNTs) in water. For evaluating mechanical property such as load-deflection, tests were performed on CNT admixed prisms under flexure. The outcomes were then compared with plain mortar prisms. An attempt has also been made to explore the optimum concentration of MWCNT additions that will give ideal performance with respect to mechanical and durability properties. Flexural and compressive strength is enhanced by 25% and 19%, respectively compared to control prisms at 28 days when CNT was used in the cementitious matrix. Both porosity and water absorption are reduced by about 25% at 28 days. Based on the parametric study, a tentative optimum CNT concentration (0.3% by weight of cement) has been proposed. SEM images shows perfect crack bridging mechanism; several of the CNTs were shown as crack arrestor across the fine cracks along with some CNTs breakage

    A Day Through My Eyes: Improving Visual Perceptual Training For School Staff Members Working With Students With Autism Spectrum Disorder

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    A Day Through My Eyes focuses on the topic of visual perception in school-age children with autism spectrum disorder (ASD). This program addresses a need to improve the training, knowledge, and skills within the area of visual perception amongst school staff members working at Bridgeway Academy. This program contains three interrelated components to address these needs: an all staff training, development of an occupational therapy based assessment tool for visual perception, and the training of occupational therapy staff members on the use of the assessment too as well as incorporating visual perception resources into treatment. Results of this program indicate an increase in knowledge and skills of the staff members regarding the topic of addressing visual perception with individuals with autism. This study demonstrates a need for similar and more extensive programing in other facilities working with this population

    Intracranial hypotension with multiple complications: an unusual case report

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    Background. Undiagnosed intracranial hypotension can result in several complications including subdural hematoma (SDH), subarachnoid hemorrhage (SAH), dural venous sinuses thrombosis (CVT), cranial nerve palsies, and stupor resulting from sagging of the brain. It is rare to see all the complications in one patient. Furthermore, imaging of the brain vasculature may reveal incidental asymptomatic small aneurysms. Given the combination of these imaging findings and a severe headache, the patients are often confused to have a primary subarachnoid hemorrhage. Case Report. We present a patient with spontaneous intracranial hypotension (SIH) who had an incidental ophthalmic artery aneurysm on MR imaging, and this presentation led to coiling of the aneurysm. The key aspect in the history postural headaches was missed, and this led to life threatening complications and unnecessary interventions. Revisiting the history and significant improvement in symptoms following an epidural blood patch resulted in the diagnosis of SIH. Conclusion. We strongly emphasize that appropriate history taking is the key in the diagnosis of SIH and providing timely treatment with an epidural blood patch could prevent potentially life threatening complications

    Intra-arterial versus intra-venous thrombolysis within and after the first 3 hours of stroke onset

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    The NINDS trial demonstrated for the first time the effectiveness of intravenous thrombolysis in improving outcome after acute ischemic stroke. The absolute benefit of this intervention was 11–13% greater chance of being normal or near normal (MRS ≤ 1) at 3 months. However, if patients with severe stroke were considered (NIHSS ≥ 20), the absolute benefit dropped to 5–6%, indicating that IV thrombolysis may not be as effective for large vessel occlusion. This observation was further supported by TCD studies that clearly demonstrated that large artery occlusions had a recanalization rate of 13–18% with IV rt-PA. Intra-arterial thrombolysis achieves recanalization rates of 60–70%. Since tissue viability is clearly important, it is time to stop defining rigid time windows and if there is a large penumbra (20–50%) and the occlusion is in a large artery, there exists a logic and a growing evidence to consider either bridge therapy or direct intra-arterial therapy

    Identification and detection of anomalies through SSME data analysis

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    The goal of the ongoing research described in this paper is to analyze real-time ground test data in order to identify patterns associated with the anomalous engine behavior, and on the basis of this analysis to develop an expert system which detects anomalous engine behavior in the early stages of fault development. A prototype of the expert system has been developed and tested on the high frequency data of two SSME tests, namely Test #901-0516 and Test #904-044. The comparison of our results with the post-test analyses indicates that the expert system detected the presence of the anomalies in a significantly early stage of fault development

    Watershed Infarcts in Acute Hypereosinophilia

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    Suitable low Global Warming Potential (GWP) refrigerants for two-speed Heat Pumps for residential applications based on simulated performance

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    The next generation of heat pumps (HPs), including those intended for cold climates must transition to low-global warming potential (GWP) refrigerants to mitigate climate change. HPs must be designed to alleviate the problems of excessive discharge temperatures, low suction pressure and high-pressure ratio at low ambient conditions and insufficient heating capacity relative to the rated heating capacity. In this paper we recognize those concerns. Low global warming potential (GWP) refrigerants are screened based on the shape of their temperature-entropy (T-S) saturation boundary. Simulations of the two-stage HP with low GWP refrigerants (R32, R454B, R466A, and R452B) to replace R-410A was accomplished using the DOE/ORNL Heat Pump Design Model. Systemic inefficiency was addressed by component-level exergy analysis to refine design options. HPs with low-GWP refrigerants address issues of reducing energy consumption, lowering carbon footprint, and enabling environmental sustainability

    Indo-Pakistan normalization process: The role of CBMS in the post-Cold War Era

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    Arms Control & Domestic and International Security (ACDIS
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