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BENDING BEHAVIOR OF EmPTY AND FOAm-FILLED ALUmINUm TUBES WITH DIFFERENT CROSS-SECTIONS

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Acta mechanica Solida Sinica 2012年第6期25卷 616-626页

作者： m. H. Shojaeifard H. R. Zarei R. Talebitooti m. mehdikhanlo School of Automotive Engineering Iran University of Science and Technology Faculty of Aerospace Engineering Aeronautical University of Science and Technology

In this paper, the energy absorption mechanism of empty and foam-filled aluminum tubes with different cross-sections （circular, square and elliptic） under bending load is investigated numerically. The load-displacement curves of the present simulations are in very good agreement with those of published experimental data. Here, the existing analytical formulations are reviewed and compared with experimental results. In addition, the effects of different cross-sections and wall thicknesses on the energy absorption capacity and specific energy absorption of these tubes are fully investigated. The results indicate that the energy absorption of an elliptic foam-filled tube with 1.5 mm and 2 mm thicknesses increases about 45% and 73% in comparison with a square one, respectively.

关键词： plastic bending foam filled energy absorption

Comparative study of Anaplasma parasites in tick carrying buffaloes and cattle

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第11期6卷 1057-1062页

作者： RAJPUT Z.I. 胡松华 ARIJO A.G. HABIB m. KHALID m. Directorate of Animal Husbandry Shahbaz Building Block-A Sindh Hyderabad Pakistan Department of Veterinary medicine School of Animal Science Zhejiang University Department of Parasitology Sindh Agriculture UniversityTando Jam Pakistan Department of Veterinary microbiology University of Agriculture Faisalabad Pakistan Department of Biological Sciences Quaid-e-Azam University Islamabad Pakistan

A comparative study on the prevalence of Anaplasma parasite was conducted on ticks carrying buffaloes and cattle. Five hundred blood samples of both animals (250 of each) were collected during February, march and April. Thin blood smears on glass slides were made, fixed in 100% methyl alcohol and examined. microscopic examination revealed that 205 (41%) animals had Anaplasma parasites, out of which 89, 44 and 72 animals had Anaplasma marginale, Anaplasma centrale and mixed infection respectively. Infected buffaloes and cattle were 75 and 130 respectively. The infection in female was 53 and 92 in buffaloes and cattle respectively. Twenty-two and 92 blood samples of male were found positive in buffaloes and cattle respectively. Com- parative study revealed that the cattle were 26.82% more susceptible than buffaloes. The parasite prevailing percentage in female of both animals was slightly higher than that of the male. This investigation was aimed at studying the comparative prevalence of Anaplasma parasite in tick carrying buffaloes and cattle.

关键词： Anaplasma marginale Anaplasma centrale Buffaloes Cattle Ticks

Experimental results of the tribology of aluminum measured with a pin-on-disk tribometer: Testing configuration and additive effects

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Friction 2016年第2期4卷 124-134页

作者： S.m.H.AHmER L.S.JAN m.A.SIDDIG S.F.abdULLAH Department of Physics GS Faculty Yanbu University College Yanbu al Sinayiah 41912 Kingdom of Saudi Arabia Department of Physics Faculty of Science and Technology al Neelain University Khartoum 11111 Sudan mechanical Engineering Department UNITEN Kajang 43009 Malaysia

The friction coefficient, wear rate, and wear coefficient of the aluminum metal surface were measured at room temperature (≈300 K) with a pin-on-disk machine at a fixed load of 196.2 N. Two different testing configurations were adopted: (1) aluminum pin vs. Helix oil-on-steel disk (AHS) and (2) aluminum pin vs. 10% Polytron plus 90% helix oil-on-steel disk (APS). In the AHS configuration, the wear of the aluminum surface was found to be approximately 70 μm; however, in the APS configuration the wear dropped to 20 μm, revealing a marked decrement of one-third of the wear of aluminum. The volume wear rate of the metal in the unaided Helix oil was estimated to be 1.28×10–3 mm3/min. The additive minimized the volume wear rate of the aluminum metal by orders of magnitude to 6.08×10–5 mm3/min. Similarly, the wear coefficient of the aluminum pin, calculated in the AHS configuration, rendered a value of 1.27×10–10 m2/N. In the APS configuration, the same parameter was 4.22×10–11 m2/N, that is to say, an order of magnitude lower than the preceding value. The observed coefficient of friction for aluminum is 0.012 in Helix oil and falls to a remarkably lower value of 0.004 through the Polytron additive. The experimental findings demonstrate that Polytron additive substantially lessens the wear of the aluminum surface; in effect, the wear coefficient and the wear rate decline linearly. This singularity may be linked to the ability of Polytron to impregnate the crystal structure of the metal due to its ionic character and the consequent adherence to the metallic surface as a hard surface layer.

关键词： antiwear Polytron additive aluminum metal lubrication friction

Analog performance of double gate junctionless tunnel field effect transistor

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Journal of Semiconductors 2014年第7期35卷 37-41页

作者： m.W.Akram Bahniman Ghosh Department of Electrical Engineering Indian Institute of Technology KanpurKanpurUttar Pradesh208016India microelectronics Research Center 10100 Burnet RoadBldg.160University of Texas at AustinAustinTX78758USA

For the first time, we investigate the analog performance of n-type double gate junctionless tunnel field effect transistor （DG-JLTFET） and the results are compared with the conventional n-type double gate tunnel field effect transistor （DG-TFET） counterpart. Using extensive device simulations, the two devices are compared with the following analog performance parameters, namely transconductance, output conductance, output resistance, intrinsic gain, total gate capacitance and unity gain frequency. From the device simulation results, DG-JLTFET is found to have significantly better analog performance as compared to DG-TFET.

关键词： junctionless field effect transistor tunnel field effect transistor subthreshold slope

Experimental and numerical study of fence effects on dust emission into atmosphere from open storage piles

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Journal of Central South University 2011年第2期18卷 411-419页

作者： S.TORNO J.TORA-O m mENéNDEZ m.GENT I.áLVAREZ mining and Civil Works Research Group Oviedo University School of mines Oviedo University

The results obtained from the research on the behaviour of fences (solid and porous) in the protection against particulated material emission to the atmosphere from open storage piles,are presented. This research was carried out through computational fluid dynamics (CFD) simulation by software Ansys CFX-10.0 in 3D,with K-epsilon being considered in the turbulence model. The efficiency of the use of porous fences as a protection against the wind flow,which interacts with an open storage pile,is shown. The use of these fences (when porosity is ε=30%) allows the reduction of wind flow velocity which interacts with the pile in comparison with the case of no use of fences (when porosity is 100%). In addition,the use of porous fences makes the velocity vortex,which is formed between the solid fence (ε=0%) and the pile,disappear,reducing the particle emission to the atmosphere by 78%.

关键词： open storage pile air pollution particle emission wind erosion porous fence computational fluid dynamics

New methods for processing and interpreting marine magnetic anomalies:Application to structure,oil and gas exploration,Kuril forearc,Barents and Caspian seas

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Geoscience Frontiers 2013年第1期4卷 73-85页

作者： A.m.Gorodnitskiy Yu.V.Brusilovskiy A.N.Ivanenko A.m.Filin N.A.Shishkina Shirshov Institute of Oceanology MoscowRussia

New methods are presented for processing and interpretation of shallow marine differential magnetic data, including constructing maps of offshore total magnetic anomalies with an extremely high reso- lution of up to 1-2 nT, mapping weak anomalies of 5-10 nT caused by mineralization effects at the contacts of hydrocarbons with host rocks, estimating depths to upper and lower boundaries of anom- alous magnetic sources, and estimating thickness of magnetic layers and boundaries of tectonic blocks. Horizontal dimensions of tectonic blocks in the so-called ＂seismic gap＂ region in the central Kuril Arc vary from 10 to 100 km, with typical dimensions of 25-30 km. The area of the ＂seismic gap＂ is a zone of intense tectonic activity and recent volcanism. Deep sources causing magnetic anomalies in the area are similar to the ＂magnetic belt＂ near Hokkaido. In the southern and central parts of Barents Sea, tectonic blocks with widths of 30-100 kin, and upper and lower boundaries of magnetic layers ranging from depths of 10 to 5 km and 18 to 30 km are calculated. models of the magnetic layer underlying the mezen Basin in an inland part of the White Sea-Barents Sea paleorift indicate depths to the lower boundary of the layer of 12-30 km. Weak local magnetic anomalies of 2-5 nT in the northern and central Caspian Sea were identified using the new methods, and drilling confirms that the anomalies are related to concentrations of hydrocarbon. Two layers causing magnetic anomalies are identified in the northern Caspian Sea from magnetic anomaly spectra. The upper layer lies immediately beneath the sea bottom and the lower layer occurs at depths between 30-40 m and 150-200 m.

关键词： Geophysical survey magnetic data processing Hydrocarbon prospecting Kuril Arc Barents Sea Caspian Sea

Therapeutic Potential of Glucagon-Like Peptide-1 Cleavage Product for Alzheimer’s Disease

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Neuroscience Bulletin 2019年第5期35卷 934-936页

作者： Stephen m. Day Tao ma Department of Internal medicine Gerontology and Geriatric Medicine Wake Forest School of Medicine Winston-Salem NC 27157 USA Department of Physiology and Pharmacology Wake Forest School of Medicine Winston-Salem NC 27157 USA Department of Neurobiology and Anatomy Wake Forest School of Medicine Winston-Salem NC 27157 USA

Alzheimer’s disease (AD) is a devastating neurodegenerative disease and the most common form of dementia in the elderly. Concurrent with an aging population, the incidence of AD has been rising steadily and become a global threat to public health [1]. Unfortunately, there are currently no effective interventions that can cure AD or slow its progression, and recently finished clinical trials targeting brain amyloid-b (Ab) accumulation have not succeeded in improving cognitive impairments in AD patients [1]. Thus, it is necessary and urgent to identify alternative diseasemodifying strategies to alleviate AD pathophysiology. In this perspective article, we focus on glucagon-like peptide- 1 (GLP-1), specifically its natural cleavage product GLP-1 (9-36), as a potential therapeutic approach for AD.

关键词： Alzheimer GLP-1 its AD has can is

Investigation of Quantitative Relationship between Adsorbed Amount of Solute and Solvent Concentration at Relatively High Solute Concentration by Frontal Analysis in RPLC

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Chinese Journal of Chemistry 2003年第10期21卷 1339-1343页

作者：王彦耿信笃 ZEBOLSKY Don m. Institute of modern Separation Science Department of Chemistry

In previous paper a new adsorption isotherm which relates the amount of solute absorbed to the solvent concentration is proposed and simplified, and it only can be used at lower solute concentration. In this article the scope of the new adsorption isotherm is extended and the expressions with three and four parameters are obtained. The equations with multi parameters are valid when the adsorbed amounts are larger and show non linear logarithmic relationships. Tests with a homologue of aromatic alcohols by frontal analysis in reversed phase liquid chromatography demonstrate that the experimental results fit those equations well. In addition, the predicted values by the multi parameters were found to fit the experimental values well also. The parameters have physical meaning only for the two parameter equation for the aromatic alcohols.

关键词： solid liquid adsorption solvent concentration stoichiometric displacement adsorption isotherm reversed phase liquid chromatography frontal analysis phenyl alcohol

Neuromodulation and ablation with focused ultrasound-toward the future of noninvasive brain therapy

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Neural Regeneration Research 2019年第9期14卷 1509-1510页

作者： Anton Fomenko Andres m.Lozano Krembil Research Institute University Health NetworkTorontoCanada Division of Neurosurgery Toronto Western HospitalTorontoCanada

With an aging patient population and an increased burden of neurological disease,the demand for noninvasive alternatives to open neurosurgical procedures is *** or minimally invasive approaches to targeting brain regions include transcranial magnetic stimulation(TmS),transcranial direct current stimulation,temporally interfering electric fields,and focused ultrasound(FUS).Among these modalities,FUS offers a unique combination of target specificity,deep brain penetration,and compatibility with real-time structural and thermal monitoring using magnetic resonance imaging(mRI)and mR *** on the intensity and frequency used,ultrasound can have either modulating or ablative effects on brain ***-intensity mR-guided FUS(mRgFUS)is a noninvasive and effective alternative to conventional deep-brain stimulation and radiofrequency lesioning for essential tremor(ET),and is being investigated for other movement disorders,particularly Parkinson’s *** clinical implementation of high-intensity ultrasound is challenged by limitations in target selection precision,technical barriers(such as variable penetration and heat deposition)and the possibility of lesion-related adverse effects(Schwartz et al.,2018).Emerging studies,including those from our group(Boutet et al.,2018)are striving to refine targeting of mRgFUS to improve safety and patient clinical *** the same time,low-intensity FUS(LIFUS)has been found to safely modulate brain activity in rodents,primates,and healthy human subjects(Fomenko et al.,2018).Clinical translation of LIFUS has been hampered however,by a poor understanding of the mechanisms of action,uncertainty over effective sonication parameters and intensities,and conflicting study results due to heterogeneous experimental *** this perspective,the current state of both mRgFUS ablation and LIFUS neuromodulation will be *** technical challenges to delivering ultrasound to the brain,recen

关键词： precision procedures Parkinson human same FUS can has