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Journal of materials Science & Technology 2011年第12期27卷 1113-1119页

作者： A. Alizadeh E. Taheri-Nassaj m. Hajizamani Department of materials Science and Engineering Tarbiat Modares University Faculty of materials and manufacturing Processes MUT University

In this study, aluminum alloy （Al-2 wt% Cu） matrix composites reinforced with I, 2 and 4 wt% boron carbide nanoparticles fabricated through mechanical milling with average size of 100 nm were fabricated via stir casting method at 850℃. Cast ingots of the matrix alloy and the composites were extruded at 500℃ at an extrusion ratio of 10：1 to investigate the effects of hot extrusion on the mechanical properties of the composites. The microstructures of the as-cast and the extruded composites were investigated by scanning electron microscopy （SEm）. Density measurement, hardness and tensile tests were carried out to identify the mechanical properties of the composites. The extruded samples revealed a more uniform distribution of B4C nanoparticles. Also, the extruded samples had strength and ductility values superior to those of the as-cast counterparts. In the as-cast and the extruded samples, with increasing amount of B4C nanoparticles, yield strength and tensile strength increased but e^ongation to fracture decreased.

关键词： Stir casting Hot extrusion Al matrix composite B4C nanoparticles mechanicalmilling

The germline genetics of mild-to-moderate penetrance:An intriguing role of PRAmE in multiple carcinogenesis

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Genes & Diseases 2024年第3期11卷 7-10页

作者： Diaddin Hamdan Van Tai Nguyen Justine Paris Christophe Leboeuf morad El Bouchtaoui marc Espie Anne Janin Geraldine Falgarone melanie Di Benedetto Guithem Bousquet Universite de Paris Cite INSERMUMR_S942MASCOTParis F-75006France Hopital La Porte Verte Versailles F-78004France National Cancer Hospital Cancer Research and Clinical Trials CenterHaNoi100000VietNam AP-HP-Hopital Saint Louis Centre de Maladies du SeinParisF-75010France Universite Sorbonne Paris Nord Bobigny F-93000France AP-HP-Hopital Avicenne Unite de Medecine AmbulatoireBobigny F-93000France

Germline genetics of high penetrance such as BRCA genes,mutations might be sufficient for carcinogenesis,but this only explains fewer than 10%of *** assume that most cancers are the result of germline mutations of low to moderate penetrance,combined with acquired mutations due to external carcinogenic *** their accumulation over time,aging is associated with an increased risk of multiple cancer development in a given *** decades,germline genetics have been based on familial linkage studies enabling most high-penetrance genes to be *** recently,population-wide studies have led to the identification of considerable numbers of polymorphisms associated with cancer ***,most of them are of unknown functional value,thus limiting their translational application.

关键词： carcinogenesis BRCA linkage

Ear Field Adaptive Noise Control for Snoring:An Real-time Experimental Approach

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 158-166页

作者： Lichuan Liu Karunakar Reddy Pottim Sen m.Kuo IEEE the Electrical Engineering Department Northern Illinois University the Department of Electrical Engineering Chung Yuan Christian University

In this paper, an active noise control(ANC) system is developed to provide an effective and non-intrusive solution for reducing loud snoring to provide a quiet environment for a snorer's bed partner. An adaptive least mean square(LmS)algorithm optimized for different kinds of snore signals is introduced and theoretically analyzed. Also, a residual noise masking approach is proposed to further reduce the effect of the snore noise without interfering with the LmS algorithm. Computer simulations followed by real-time experiments are conducted to demonstrate the feasibility of the snore ANC systems based on a pillow setup. For the optimum effect based on the characteristics of human hearing, the performance of the proposed approach is evaluated by using the multi-channel feedforward ANC systems based on the filtered-X least mean square(FXLmS) *** with a traditional headboard setup for snoring noise control, the proposed snore ANC systems optimized for ear field operation yield much higher noise reduction around the ears of the snorer's bed partner.

关键词： Active noise control (ANC) audio integrated ANC ear field filtered-X least mean square (FXLmS) snore multi-channel

Newmark design spectra considering earthquake magnitudes and site categories

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Earthquake Engineering and Engineering Vibration 2016年第3期15卷 519-535页

作者： Bo Li Wei-Chau Xie m.D.Pandey Department of Civil and Environmental Engineering University of Waterloo

Newmark design spectra have been implemented in many building codes, especially in building codes for critical structures. Previous studies show that Newmark design spectra exhibit lower amplitudes at high frequencies and larger amplitudes at low frequencies in comparison with spectra developed by statistical methods. To resolve this problem, this study considers three suites of ground motions recorded at three types of sites. Using these ground motions, influences of the shear-wave velocity, earthquake magnitudes, source-to-site distances on the ratios of ground motion parameters are studied, and spectrum amplification factors are statistically calculated. Spectral bounds for combinations of three site categories and two cases of earthquake magnitudes are estimated. Site design spectrum coefficients for the three site categories considering earthquake magnitudes are established. The problems of Newmark design spectra could be resolved by using the site design spectrum coefficients to modify the spectral values of Newmark design spectra in the acceleration sensitive, velocity sensitive, and displacement sensitive regions.

关键词： Newmark design spectrum site design spectrum coefficients site conditions

Local and range-wide distribution of song types suggest Ovenbirds(Seiurus aurocapilla)have song neighborhoods but not macro-dialects

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Avian Research 2023年第2期14卷 191-199页

作者： Patrick m.Jagielski Jennifer R.Foote Department of Biology Algoma UniversitySault Ste.MarieONCanada

The song systems of oscine passerines(songbirds)are complex and *** songs are used for both mate attraction and territory defense and are therefore important signals for survival and reproduction,comprehensive knowledge of within and among species song structure and distribution is informative for understanding the evolution of song repertoires and vocal *** this study,we explored variation in the song structure of the Ovenbird(Seiurus aurocapilla),a widespread warbler(Family Parulidae)found in North American *** analyzed recordings from the 2021 breeding season to assess song type variation at a local(n=158 birds;Sault ***,ON)and breeding range scale(n=512 birds;eBird).We characterized the local song types and tested whether Ovenbirds share song types with their neighbors more often than expected by *** then characterized song types of Ovenbirds across the breeding range to determine whether any geographic pattern of song clustering exists(i.e.,macro-dialects).We found 10 distinct song types and some evidence for song type clustering at the local study site(i.e.,song neighborhoods).We found 7 of those 10 song types throughout the breeding range and identified an additional 24 types that were not recorded in our local *** found no evidence for song dialects across the Ovenbird breeding *** study contributes to our understanding of Ovenbird song while simultaneously adding to our understanding of geographic structuring of warbler *** work contributes to delineating a more comprehensive understanding of factors affecting dialect development for this diverse group of songbirds.

关键词： Dialects eBird Geographic variation Ovenbird Parulidae Seiurus aurocapilla Song type

Waste materials to Replace Natural Resources

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武汉理工大学学报 2010年第17期32卷 35-42页

作者： VAN DE VEN m F C mOLENAAR A A A POOT m R Delft University of Technology

A number of waste materials were studied on their application into asphalt mixtures. materials tested were plastic waste as (soft) granular material,ceramic waste from electrical insulators,foundry sand and sintered granulate from burned household waste. Both plastic waste,crushed ceramics and large fractions of sintered household waste could be used as partial replacement for coarse aggregates. Foundry sand could partially replace natural sand in asphalt mixtures. The first step of the study was to find out if the waste materials could satisfy basic requirements and for some if their leaching behavior was acceptable. In the next phase mixtures were designed and mechanical tests were done on several mixtures with waste components to determine indirect tensile strength,stiffness,fatigue. In order to estimate the water sensitivity of some mixtures,retained indirect tension tests were done. The properties are reported and compared with each other and reference mixtures. From the research it becomes clear that it takes a lot of work to replace virgin materials in asphalt mixtures with waste materials.

关键词： waste materials plastic ceramic sintered household waste leaching,mechanical properties

Simulation and optimization of an industrial gas condensate stabilization unit to modify LPG and NGL production with minimizing CO2 emission to the environment

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Chinese Journal of Chemical Engineering 2017年第3期25卷 338-346页

作者： m.Bahmani J.Shariati A.Nemati Rouzbahani Young Researchers and Elite Club Darab BranchIslamic Azad UniversityDarabIran Department of Chemical Engineering Darab BranchIslamic Azad UniversityDarabIran

In the present study, a great effort was made to improve the performance of an industrial liquefied petroleum gas(LPG) and natural gas liquid(NGL) production unit in one of the major gas refinery located at Pars special economic zone in Iran. To demonstrate and obtain the optimal condition, the unit was simulated by using a steady-state flowsheet simulator, i.e. Aspen Plus, under different operational conditions. According to the simulation results,the unit was not operational under its optimal conditions due to some defects in the cooling system at top stage of the debutanizer tower(DBT) during hot and humid seasons. Additionally, the vapor pressure of produced LPG and accordingly the amount of its flaring were decreased by reducing the temperature of debutanizer tower at top stages. In the optimization section, the DBT condenser and reboiler heat duty, temperature, and pressure were regulated as adjustable parameters. The simulation results demonstrated that by applying the optimum suggestion in the hot months, the reflux stream temperature was reached about 55 ℃ which caused an efficient increment in LPG production(about 4%) with adjusting the propane component in LPG, based on the standard range as the plant criteria. moreover, after applying modifications, about 750 t of LPG product was saved from flaring during five hot months of the year, which resulted in 360000 USD extra annual income for the ***, from environmental point of view, this optimization caused to reduce 81 t of CO_2 emission to the environment. Therefore, the current investigation must be introduced as a friendly environmentally process.

关键词： LPG NGL Simulation Optimization CO2 emission

Astrocyte in prion disease: a double-edged sword

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Neural Regeneration Research 2022年第8期17卷 1659-1665页

作者： Waqas Tahir Simrika Thapa Hermann m.Schatzl Department of Comparative Biology&Experimental medicine Faculty of Veterinary MedicineUniversity of CalgaryCalgaryABCanada Calgary Prion Research Unit University of CalgaryCalgaryABCanada Hotchkiss Brain Institute University of CalgaryCalgaryABCanada

Prion diseases are infectious protein misfolding disorders of the central nervous system that result from misfolding of the cellular prion protein(PrPC)into the pathologic isoform *** hallmarks of prion disease are depositions of pathological prion protein PrPSc,neuronal loss,spongiform degeneration and astrogliosis in the *** diseases affect human and animals,there is no effective therapy,and they invariably remain *** a long time,neuronal loss was considered the sole reason for neurodegeneration in prion pathogenesis,and the contribution of non-neuronal cells like microglia and astrocytes was considered less *** evidence suggests that neurodegeneration during prion pathogenesis is a consequence of a complex interplay between neuronal and non-neuronal cells in the brain,but the exact role of these non-neuronal cells during prion pathology is still *** are non-neuronal cells that regulate brain homeostasis under physiological ***,astrocytes can deposit PrPSc aggregates and propagate prions in prion-infected ***,sub-populations of reactive astrocytes that include neurotrophic and neurotoxic species have been identified,differentially expressed in the brain during prion *** the exact role of astrocytes in prion disease is hampered by the lack of in vitro models of prion-infected ***,we established a murine astrocyte cell line persistently infected with mouse-adapted prions,and showed how such astrocytes differentially process various prion *** the complexity of the role of astrocytes in prion pathogenesis,we need more in vitro and in vivo models for exploring the contribution of sub-populations of reactive astrocytes,their differential regulation of signaling cascades,and the interaction with neurons and microglia during prion *** will help to establish novel in vivo models and define new therapeutic targets against prion

关键词： Alzheimer’s disease astrocytes central nervous system Creutzfeldt-Jakob disease glial cells neurodegeneration prion prion disease prion protein scrapie

Comparisons of electrical and optical properties between graphene and silicene A review

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Chinese Physics B 2018年第2期27卷 299-313页

作者： Wirth-Lima A J Silva m G Sombra A S B Laboratory of Telecommunications and materials Science and Engineering-www.locem.ufc.br-Fortaleza CearaBrazil Department of Physics Science CenterFederal University of Ceara(U.F C.)-FortalezaCear4Brazil State University of Vale do Acarau SobralCeardBrasil

Two-dimensional （2D） metamaterials are considered to be of enormous relevance to the progress of all exact sciences. Since the discovery of graphene, researchers have increasingly investigated in depth the details of electrical/optical proper- ties pertinent to other 2D metamaterials, including those relating to the silicene. In this review are included the details and comparisons of the atomic structures, energy diagram bands, substrates, charge densities, charge mobilities, conductivities, absorptions, electrical permittivities, dispersion relations of the wave vectors, and supported electromagnetic modes related to graphene and silicene. Hence, this review can help readers to acquire, recover or increase the necessary technological basis for the development of more specific studies on graphene and silicene.

关键词： graphene silicene electrical/optical properties

Study on demand and characteristics of parking system in urban areas:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第1期7卷 111-124页

作者： Janak Parmar Pritikana Das Sanjaykumar m.Dave Department of Civil Engineering Faculty of Technology and EngineeringThe Maharaja Sayajirao University of BarodaVadodara 390001India Transportation Planning and Environment Division CSIR-Central Road Research InstituteNew Delhi 110025India

The increasing rate of private car usage in the urban areas as a result of fast-growing economy,derelict policies and subsidies are the main causes making car parking one of the main concerns for transport and traffic management all over the *** coordination between parking policies and traffic management revealed how parking is becoming a barrier to the through-traffic ***,it is responsible for the inefficient use of available resources,even the decisions are made on an ad-hoc basis while making ***,it is necessary to understand the parking choice behaviour and actual demand of parking *** the last three decades,ample studies have been done to evaluate parking characteristics,to estimate the demand for parking and on driver’s behaviour while choosing the parking *** paper integrates all these aspects and presents the state-of-the-art review of models and studies on the parking *** related to and due to the parking,various parking characteristics and their applications,parking choice behaviour of drivers,development of demand models considering various factors and review of parking policies as an integral part of the urban transport system are discussed in *** underdeveloped,authors found the literatures suggest that greater attention should be given to metrics like ease of access,walk time,parking charges,parking guidance and information system,management,etc.,at all stages of planning and policy *** together,mentioned studies demonstrate useful information concerning the entire parking *** also provides useful information to the planners and policy makers for planning,designing and evaluating parking system.

关键词： Transportation engineering Parking demand and capacity Parking characteristics Parking choice behaviour Policy guideline Planning and management