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Dielectric Analysis of Response Time in Electrorheological Fluids Developed for medical Devices

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American Journal of Analytical Chemistry 2011年第2期2卷 85-92页

作者： Naullage I. Perera manik Pavan maheswaram Dhruthiman mantheni Dhanuja D. Perera m. Ellen matthews Alan Riga Tobili sam Yellowe 不详

Three electrorheological fluids (ERFs) of recently synthesized *** and Cellulose fluids as well as a commercial product from Fludicon? (Germany), were evaluated with a two-electrode probe unit and by Dielectric Analysis (DEA). The study was a part of an ongoing medical device development project. The dielectric response times were calculated using the critical peak frequency in a corresponding Debye plot of Tan Delta (loss factor/permittivity) vs. log frequency. The DEA revealed the response times (tau, τ) in ms. The Fludicon? ERF was DEA durable (repeat cycles produced same results) and the τ was temperature dependent: 16 ms at 25°C and 0.16 ms at 80°C. The Cellulose ERF was somewhat DEA durable and the τ was 5.5 ms at 25°C and 0.21 ms at 80°C. The response times were logarithmic with the temperature (°C) with a correlation coefficient of >0.98 for the Cellulose and Fludicon? ERFs. The Polyaniline ERF had a τ of 53 ms at 25°C in the 1st DEA run and there was no indication of a τ for the remaining DEA tests.

关键词： ERF Tan Delta DEA Fibrillation Debye Plot Response Time

Fecal lactoferrin accurately reflects mucosal inflammation in inflammatory bowel disease

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World Journal of Gastrointestinal Pathophysiology 2019年第5期10卷 54-63页

作者： marrieth G Rubio Kofi Amo-mensah James m Gray Vu Q Nguyen sam Nakat Douglas Grider Kim Love James H Boone Dario Sorrentino IBD Center-Division of Gastroenterology Virginia Tech Carilion School of MedicineRoanokeVA 24016United States Department of Radiology Virginia Tech Carilion School of MedicineRoanokeVA 24016United States Department of Basic Science Education Virginia Tech Carilion School of medicine and Dominion Pathology Associates RoanokeVA 24016United States K.R.Love Quantitative Consulting and Collaboration AthensGA 30605United States Research and Development TECHLAB IncBlacksburgVA 24060United States Department of Clinical and Experimental medical Sciences University of Udine School of MedicineUdine 33100Italy

BACKGROUND Studies have demonstrated a potential role for fecal biomarkers such as fecal calprotectin(FC)and fecal lactoferrin(FL)in monitoring inflammatory bowel diseases(IBD)-Crohn's disease(CD)and ulcerative colitis(UC).However,their correlation to endoscopic scores,disease severity and affected intestinal surface has not been extensively *** To correlate FL,and for comparison white blood cell(WBC)and C-reactive protein(CRP),with endoscopic scores,disease extent and location in CD and *** Retrospective analysis in 188 patients who had FL,CRP and WBC determined within 30 d of *** location,disease extent(number of intestinal segments involved),disease severity(determined by endoscopic scores),timing of FL testing in relation to colonoscopy,as well as the use of effective fast acting medications(steroids and biologics)between colonoscopy and FL measurement,were *** In 131 CD and 57 UC patients,both CRP and FL-but not WBC-distinguished disease severity(inactive,mild,moderate,severe).In patients receiving fastacting(steroids or biologics)treatment in between FL and colonoscopy,FL showed a higher correlation to endoscopic scores when tested before vs after the procedure(r=0.596,Pmple Endoscopic Score for CD;and r=0.402,P=0.01 vs r=0.054 P=0.84 for Disease Activity Index).Finally,FL was significantly correlated with the diseased mucosal surface(colon-ileocolon>small bowel)and the number of inflamed colon *** FL and CRP separated disease severity categories with FL showing lower discriminating *** showed a close correlation with the involved mucosal surface and with disease extent and was more closely correlated to endoscopy when determined before the procedure–this indicating that inflammatory activity changes associated with therapy might be rapidly reflected by FL *** can accurately and timely characterize intestinal inflammation in IBD.

关键词： Inflammatory bowel disease Crohn’s disease Ulcerative colitis Fecal lactoferrin C-reactive protein White blood cell count mucosal inflammation

Direct Current Generation in Carbon Nanotubes by Terahertz Field

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World Journal of Condensed matter Physics 2016年第1期6卷 56-62页

作者： Sulemana S. Abukari Frederick sam samuel Y. mensah Natalia G. mensah Rabiu musah Anthony Twum Patrick m. Amoah Alfred Owusu Department of Physics Laser and Fibre Optics Centre University of Cape Coast Cape Coast Ghana Department of mathematics University of Cape Coast Cape Coast Ghana Department of Applied Physics University for Development Studies Navorongo Ghana

We report on a theoretical investigation of a direct current generation in carbon nanotubes (CNTs) that are stimulated axially by terahertz (THz) field. We consider the kinetic approach based on the semiclassical Boltzmann’s transport equation with constant relaxation time approximation, together with the energy spectrum of an electron in the tight-binding approximation. Our results indicate that for strong THz-fields, there is simultaneous generation of DC current in the axial and circumferential directions of the CNTs, even at room temperature. We found that a THz-field can induce a negative conductivity in the CNTs that leads to the THz field induced DC current. For varying amplitude of the THz-field, the current density decreases rapidly and modulates around zero with interval of negative conductivity. The interval decreases with increasing the amplitude of the THz-field. We show that the THz-field can cause fast switching from a zero DC current to a finite DC current due to the quasi-ballistic transport, and that electron scattering is a necessary condition for switching.

关键词： Carbon Nanotubes Terahertz Fields DC Voltage Generation Negative Conductivity Electron Scattering Ballistic Transport

晚古生代冈瓦纳的演化:长逾13500km的基墨利超级地体的裂离及其向亚洲的漂移(英文)

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地球学报 2012年第S1期33卷 2-3页

作者： Jason R.ALI Jonathan C.AITCHISON Haz m.C.CHEUNG sam S.Y.CHIK SUN Ya-dong Department of Earth Sciences University of Hong KongPokfulam Road School of Geosciences University of SydneySydneyNSW 2006Australia Faculty of Earth Sciences China University of Geosciences School of Earth and Environment University of LeedsLeeds LS2 9JTUK

The Cimmerian terrane forms an almost unbroken chain stretching >13,500 km,from central southern Europe to western Indonesia,via SE Europe,the middle East,Afghanistan,Tibet,SW China and ***,it is Earth’s most spectac... 详细信息

关键词： Cimmerian terrane Paleomagnetism Baoshan Block Sibumasu Block

Detection of Human Pharmaceuticals in the Surface Water of East Fork Stones River

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Journal of Water Resource and Protection 2020年第3期12卷 240-259页

作者： Ravneet Kaur Anonya Akuley-Amenyenu Karnita G. Garner sam O. Dennis Department of Agricultural and Environmental Sciences College of Agriculture Tennessee State University Nashville TN USA Alabama Cooperative Extension System Alabama A&M University Normal AL USA

Pharmaceuticals have been detected nationwide in different environmental matrices including wastewater effluents and surface water. In recent studies, pharmaceuticals have also been found in aquatic plants, fish tissues and plasma of shark bulls. Pharmaceuticals that were detected as indicated in published literature, included steroids, prescription drugs such as antibiotics, anti-depressants, anti-inflammatory drugs, hormones and over the counter (OTC) drugs. We conducted a monitoring study to detect the presence of pharmaceuticals in East fork of the Stones River located in Rutherford County in middle Tennessee. East Fork Stones River is a six (6) order river that drains a large portion of Rutherford County including murfreesboro, Tennessee. Grab water samples were collected from Stones River for three seasons: (summer and fall of 2014 and 2015 and winter of 2015 and 2016) each year. Water quality parameters were also determined in situ using Eureka Water ProbesTm multi-parameter sondes. Water samples were analyzed for the presence of pharmaceutical compounds using GC-mS. Chemical Abstract Service Registry Numbers (CASRN or CAS) for detected pharmaceuticals were identified. Pharmaceuticals detected included those used for treatment of chronic alcoholism (Disulfiram: CAS # 97-77-8), a compound (Thiazolidine: CAS # 504-78-9) in the drug Thiazolidinedione which is used for the treatment of type II diabetes, a compound associated with the prevention of anti-inflammatory conditions (methyl palmitate: CAS # 112-39-0), and emollient in skincare (Undecane: CAS # 1120-21-4). While the quantitative concentrations of these drugs were not determined in this study, their qualitative presence in surface water is noteworthy.

关键词： Pharmaceuticals East Fork Stones River Surface Water Water Quality

Effects of hydrogel-encapsulated bacteria on the healing efficiency and compressive strength of concrete

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Journal of Road Engineering 2023年第2期3卷 156-170页

作者： Ricardo Hungria marwa m.Hassan momen mousa Bert S.Turner Department of Construction management Louisiana State UniversityBaton RougeLA 70803USA Department of Engineering Technology Sam Houston State UniversityHuntsvilleTX 77341USA

microbial-induced calcium carbonate precipitation is a promising technology for self-healing concrete due to its capability to seal *** main goal of this study was to evaluate the effects of adding hydrogelencapsulated bacteria on the compressive strength and the self-healing efficiency of *** achieve this objective,12 sets of mortar samples were prepared,including three different mineral precursors(magnesium acetate,calcium lactate,and sodium lactate),at two concentrations(67.76 and 75.00 mm/L),and under two different biological conditions(with and without bacteria).In addition,a set of plain mortar samples was prepared to serve as a *** each sample set,three mortar cubes and three beams were prepared and subjected to compression and flexural strength *** the compression tests,it was found that the sample containing calcium lactate along with yeast extract and bacteria displayed the best *** for the flexural tests,once cracked,the beams were subjected to 28 d of wet/dry cycles(16 h of water immersion and 8 h of drying),where the bottom crack width was monitored(at 0,3,7,14,28 d of wet/dry cycles).Once the sample with the highest healing efficiency was identified(the one containing calcium lactate and hydrogel-encapsulated bacteria),the study was scaled up to concrete *** sets of concrete cylinders(consisting of three control samples and three samples with bacteria along with calcium lactate)were tested under compression in order to evaluate the effect of the bacteria-precursor combination on the concrete mechanical *** samples that yielded the greatest compressive strength were the ones containing calcium lactate and bacteria,displaying an improvement of 17%as compared to the control ***,a flexural strength recovery analysis was performed on the concrete specimens revealing that the control showed better flexural strength recovery than the bacteriacontaining variant(41.5%vs.26.1%)after

关键词： Self-healing concrete Bioconcrete microbial induced calcium carbonate precipitation Precursor

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按钮变魔术

汽车测试报告 2009年第4期 56-57页

作者： sam Philip

新款奥迪S4的性格完全取决于1个小小的按钮，它能让S4从单纯求快的普通角色变成宝马m3的对手。

关键词：按钮魔术奥迪S4 宝马m3

Characterization of Okra Convective Drying, Influence of maturity

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Food and Nutrition Sciences 2014年第6期5卷 590-597页

作者： Ouoba Kondia Honoré Zougmoré François sam Raguilignaba Toguyeni Aboubacar Desmorieux Hélène Laboratoire des matériaux et Environnement(LAmE) Unitéde Formation et de Recherche en Sciences Exactes et Appliquée(UFR/SEA)Universitéde OuagadougouOuagadougouBurkina Faso Laboratoire d’Automatisme et de Génie des Procédés(LAGEP) UCBL1-CNRS UMR 5007-CPE LyonBat.308G43 bd du 11 Nov.1918 VilleurbanneUniversité Claude Bernard Lyon 169622LyonFrance Institut de Développement Rural Université Polytechnique de BoboBobo-DioulassoBurkina Faso

An experimental study for the drying kinetics of whole okra was carried out. In the study, different ages were considered by taking into account influence of okra maturity on its convective drying. The 2D moisture evolution inside the product and its maturity were evaluated by fitting experimental data versus drying time. The water effective diffusion coefficient of okra at different maturity states was gotten by the experimental model using Fick’s second law. A parametric study was carried out in the ranging of okra age from 2 to 7 days at 60℃, both fruits gathered on the same plant to avoid divergences due to okra varieties that can induce difference on physical structure and the chemical composition. It was found from the experimental results that okra maturity has important influence on its behaviour during convective drying. At 2, 3, 4, 5 and 7 days old, the drying effective time was respectively 780, 1000, 1155, 850 and 750 min. Effective diffusivity of the okra in this order of age was 1.38 × 10-10, 6.09 × 10-11, 1.23 × 10-11, 8.98 × 10-11, and 1.05 × 10-10 m2/s in the present study, while the average initial moisture content was respectively 12.27, 9.00, 7.53, 5.97 and 4.92 Kgw/Kgdm.

关键词： Convective Drying Okra Effective Diffusivity maturity Initial moisture Content

In-Field management Practices for mitigating Soil CO2and CH4Fluxes under Corn (Zea mays) Production System in middle Tennessee

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American Journal of Climate Change 2015年第4期4卷 367-378页

作者： sam Dennis Qi Deng Dafeng Hui Junming Wang Stephen Iwuozo Chih-Li Yu Chandra Reddy College of Agriculture Human and Natural Sciences Tennessee State University Nashville TN USA Climate and Atmospheric Science Section Illinois State Water Survey Prairie Research Institute University of Illinois at Urbana-Champaign Champaign IL USA

The United States continues to be the largest corn producer in the world. How to maximize corn yield and at the same time reduce greenhouse gas emissions, is becoming a challenging effort for growers and researchers. As a result, our understanding of the responses of soil CO2 and CH4 fluxes to agricultural practices in cornfields is still limited. We conducted a 3-yr cornfield experiment to study the responses of soil CO2 and CH4 fluxes to various agricultural practices in middle Tennessee. The agricultural practices included no-tillage + regular applications of urea ammonium nitrate (NT-URAN);no-tillage + regular applications of URAN + denitrification inhibitor (NT-inhi- bitor);no-tillage + regular applications of URAN + biochar (NT-biochar);no-tillage + 20% applications of URAN + chicken litter (NT-litter);no-tillage + split applications of URAN (NT-split);and conventional tillage + regular applications of URAN as a control (CT-URAN). A randomized complete block design was used with six replications. The same amount of fertilizer equivalent to 217 kg·N·ha-1 was applied to all of the experimental plots. The results showed that improved fertilizer and soil management, except the NT-biochar treatment significantly increased soil CO2 flux as compared to the conventional tillage (CT-URAN, 487.05 mg CO2 m-2·h-1). Soil CO2 flux increased exponentially with soil temperature (T 2 flux tended to be positively related to corn yield and/or soil moisture. Soil CH4 flux increased linearly with soil moisture in all treatments. Improved fertilizer and soil management did not alter soil CH4 flux, but significantly affected its moisture sensitivity. Our results indicated that agricultural practices enhancing corn yield may also result in a net increase in carbon emissions from soil, hence reducing the potential of carbon sequestration in croplands.

关键词： Tillage Fertilizer management Soil CO2 Flux Soil CH4 Flux Greenhouse Gases