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Particuology 2019年第5期17卷 22-29页

作者： M. Hafizur Rahman Lius Daniel Ujash Shah Xiaotao Bi John R. Grace c.Jim Lim Fluidization Research centre Department of Chemical & Biological Engineering University of British Columbia 2360 East Mall Vancouver British Columbia V6T1Z3 Canada

Operation of a dual fluidized bed, consisting of a riser as combustor and bubbling bed as gasifier, for synthesis gas production from a solid fuel requires determination of the solids circulation rate and char transfer rate. The performance relies on supplying sufficient heat from the combustor to the gasifier by circulation of solids between these two reactors. The flow rate of char is required to track the heat generated in the combustor, which supports endothermic reactions in the gasifier. Direct measurement of these two critical parameters is difficult, with the number of reported techniques capable of working at high temperatures extremely small. An indirect method was developed, using mass and energy balances over the entire system and individual reactors, to estimate the solids circulation rate and char transfer rate. There was general agreement between heat losses estimated from energy-balance calculations and from direct measurement of the outer reactor surface temperature. Under typical gasification conditions, the solids circulation fluxes were estimated to be 45.2 and 55.6 kg/(m^2 s) in two independent tests, which were in good agreement with values obtained using a thermal tracer;char transfer rates were calculated to be 1.2 and 0.6 kg/h, which were in reasonable agreement with average biomass feed rates. This method can be applied to dual gasification systems at any temperature or flow rate.

关键词： Solids circulation rate char transfer rate Pilot-plant gasifier Dual fluidized bed Mass and energy balance

Numerical investigation into the effect of backfilling on coal pillar strength in highwall mining

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International Journal of Mining Science and Technology 2018年第2期28卷 281-286页

作者： Mo S. canbulat I. Zhang c. Oh J. Shen B. Hagan P. School of Mining Engineering The University of New South Wales cSIRO Energy QCAT1 Technology Court

This paper attempts to quantify the effect of backfilling on pillar strength in highwall mining using numerical modelling. calibration against the new empirical strength formula for highwall mining was conducted to obtain the material parameters used in the numerical modelling. With the obtained coal strength parameters, three sets of backfill properties were investigated. The results reveal that the behavior of pillars varies with the type and amount of backfill as well as the pillar width to mining height ratio(w/h). In case of cohesive backfill, generally 75% backfill shows a significant increase in peak strength, and the increase in peak strength is more pronounced for the pillars having lower w/h ratios. In case of noncohesive backfill, the changes in both the peak and residual strengths with up to 92% backfill are negligible while the residual strength constantly increases after reaching the peak strength only when 100%backfill is placed. Based on the modelling results, different backfilling strategies should be considered on a case by case basis depending on the type of backfill available and desired pillar dimension.

关键词： Highwall mining Backfill coal pillar Strength Numerical modelling

calcium phosphate conversion technique:A versatile route to develop corrosion resistant hydroxyapatite coating over Mg/Mg alloys based implants

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Journal of Magnesium and Alloys 2022年第7期10卷 1821-1845页

作者： G.S.Hikku c.Arthi R.B.Jeen Robert K.Jeyasubramanian R.Murugesan Medical Bionanotechnology Faculty of Allied Health SciencesChettinad Hospital and Research InstituteChettinad Academy of Research and EducationKelambakkamTamilnadu 603103India Nanobiotechnology Amirta Centre for Nanoscience and Molecular MedicineAmirtha Vishwa VidhyapeethamErnakulamKerala 682041India Department of Mechanical Engineering AAA College of Engineering and TechnologySivakasiTamilnadu 626005India Department of chemistry Mepco Schlenk Engineering CollegeSivakasiTamilnadu 626005India Karpaga Vinayaga Institute of Medical Sciences and Research centre PalayanoorTamilnadu 603308India

Globally,vast research interest is emerging towards the development of biodegradable orthopedic implants as it overcomes the toxicity exerted by non-degradable implants when fixed in the human body for a longer *** this context,magnesium(Mg)plays a major role in the production of biodegradable implants owing to their characteristic degradation nature under the influence of body ***,Mg is one of the essential nutrients required to perform various metabolic activities by the human cells,and therefore,the degraded Mg products will be readily absorbed by the nearby ***,the higher corrosion rate in the biological environment is the primary downside of using Mg implants that liberate H2gas resulting in the formation of ***,in certain cases,Mg undergoes complete degradation before the healing of damaged bone tissue and cannot serve the purpose of providing mechanical ***,many studies have been focused on the development of different strategies to improve the corrosion-resistant behavior of Mg according to the *** this regard,the present review focused on the limitations of using pure Mg and Mg alloys for the fabrication of medical implants and how the calcium phosphate conversion coating alters the corrosive tendency through the formation of hydroxyapatite protective films for enhanced performance in medical implant applications.

关键词： Biodegradable implants Magnesium controlled corrosion Alloying Hydroxyapatite calcium phosphate conversion coating

Repeated video head impulse testing in patients is a stable measure of the passive vestibulo-ocular reflex

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Journal of Otology 2021年第3期16卷 128-137页

作者： M.Muntaseer Mahfuz Jennifer L.Millar Michael c.Schubert Laboratory of Vestibular NeuroAdaptation Department of Otolaryngology-Head and Neck SurgeryJohns Hopkins UniversityBaltimoreMD21205USA Department of Physical Medicine and Rehabilitation Johns Hopkins UniversityBaltimoreMD21205USA

Objectives The video head impulse test(vHIT)is used as a measure of compensation yet it’s stability in patients with vestibular pathology is *** 144 patients(n=72 female,mean 54.46±15.8 years)were grouped into one of three primary diagnoses(Peripheral,central,or Mixed).Subjects were further categorized based on sex(male versus female),ear(left versus right;ipsilesional versus contralesional),age(six groups ranging from 19 to 84 years),and duration between visits(five groups,mean 191.46±SE 29.42 days,median 55.5 days).The gain of the VOR during passive head rotation was measured for each semicircular canal(horizontal,anterior,posterior).Results There was no difference in the VOR gain within any semicircular canal between the two visits(horizontal:p=0.179;anterior:p=0.628;posterior:p=0.613).However,the VOR gain from the horizontal canals was higher than the vertical canals for each visit(pcantly lower(p≤0.001)horizontal semicircular canal gains at each *** was no difference in VOR gain between sex(p=0.215)or age groupings(p=0.331).Test-retest reliability of vHIT in patient subjects is good(Icc=0.801)and the VOR gain values across two separate visits were significant and positively correlated(r=0.67)regardless of sex,ear,age,or duration between *** The vHIT is a stable measure of VOR gain over two different times across a variety of vestibular patients with no influence of age or sex.

关键词： Video head impulse Vestibulo-ocular reflex Gain Peripheral vestibular hypofunction

Protective strategies to prevent patent ductus arteriosus

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chinese Medical Journal 2010年第20期123卷 2914-2918页

作者： Kris c. Sekar Department of Pediatrics Neonatal-Perinatal MedicineUniversity of Oklahoma Health Sciences CenterChildren's Hospital1200 Everett Drive 7th Floor North Pavilion Oklahoma CityOklahoma 73104USA

Ductus arteriosus is the communication between the proximal aorta and the pulmonary artery which diverts well oxygenated blood from the placenta to the systemic circulation bypassing the fluid filled lung in the fetal circulation. Therefore it is very essential for fetal survival. After birth, in term infants the ductus usually closes within the first day of life, starting with functional closure followed by anatomical closure by vascular remodeling.

关键词： ibuprofen indomethacin patent ductus arteriosus prematurity ductal ligation

A Statistical Study on Seismo-Ionospheric Anomalies of the Total Electron content for the Period of 56 M≥6.0 Earthquakes Occurring in china During 1998—2012

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空间科学学报 2013年第3期33卷 258-269页

作者： Liu J Y chen c H Tsai H F Le H Institute of Space Science National Central University center for Space and Remote Sensing Research National Central University Department of Earth Science National Cheng Kung University GPS Science and Application Research center National Central University Key Laboratory of Ionospheric Environment Institute of Geology and GeophysicsChinese Academy of Sciences

This paper reports statistical results of Seismo-Ionospheric Anomalies(SIAs) of the Total Electron content(TEc) in the Global Ionosphere Map(GIM) associated with 56 M≥6.0 earthquakes in china during 1998—*** detect SIA,a quartile-based(***-based) process is *** anomalies for the period of earthquakes without being led by magnetic storms about 10 days are further isolated and examined to confirm the SIP *** show that SIA is the TEc significantly decrease in the afternoon period 2—9 days before the earthquakes in china,which is in a good agreement with the SIA appearing before the 12 May 2008 M 8.0 Wenchuan earthquake.

关键词：电离层异常地震发生总电子含量中国统计 SIAS TEc GIM

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可伸缩产品平台优化设计的质量功能展开方法

机械工程学报 2011年第12期47卷 175-184页

作者：雒兴刚王福斌 KWONG c K 东北大学信息学院沈阳110819 东北大学机械工程与自动化学院沈阳110819 香港理工大学工业与系统工程系

为使基于产品平台的系列产品更好的满足顾客需求,提出一种基于质量功能展开的方法,可以优化设计可伸缩产品平台。该方法的主要思路是应用质量功能展开技术,建立单个产品的质量屋,确定其最优工程特性值,对每个工程特性进行敏感性分析,并... 详细信息

为使基于产品平台的系列产品更好的满足顾客需求,提出一种基于质量功能展开的方法,可以优化设计可伸缩产品平台。该方法的主要思路是应用质量功能展开技术,建立单个产品的质量屋,确定其最优工程特性值,对每个工程特性进行敏感性分析,并根据所得的工程特性敏感性指标建立优化模型,求得最优的平台工程特性值和非平台工程特性值。优化模型的目标是最大化一个产品族中所有产品变体的顾客满意度的均值,约束主要包括顾客需求和工程特性之间的函数关系以及工程特性之间的自相关函数关系。模型中采用了线性函数形式,并采用回归方法来估计函数中的参数。给出一个工业卡钳的例子来验证所提方法的可行性,案例分析的结果表明,该方法比传统的两阶段方法能获得更好的顾客满意度。

关键词：质量功能展开产品平台顾客满意度

Identification of Time-of-Flight spectra for Isochronous Mass Measurements

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chinese Physics c 2009年第S1期33卷 161-163页

作者：孙保华 H. Geissel M. Hausmann c. Kozhuharov R. Knbel Yu.A. Litvinov 孟杰 Z. Patyk T. Radon c. Scheidenberger School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Gesellschaft für Schwerionenforschung GSI 64291 Darmstadt Germany Justus-Liebig Universitt 35392 Gieβen Germany Michigan State University East Lansing Mi 48824 USA Soltan Institute for Nuclear Studies 00-681 Warszawa Poland

The Isochronous Mass Spectrometry (IMS) developed at GSI is a very effcient method for direct mass measurements of short-lived nuclides. By taking a recent IMS experiment as an example, the identification procedure of... 详细信息

关键词： Isochronous Mass Spectrometry Time-of-Flight Spectrum isotope identification

Thick Electrode Design for Facile Electron and Ion Transport:Architectures,Advanced characterization,and Modeling

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Accounts of Materials Research 2022年第4期3卷 472-483页

作者： David J.Arnot Karthik S.Mayilvahanan Zeyu Hui Kenneth J.Takeuchi Amy c.Marschilok David c.Bock Lei Wang Alan c.West Esther S.Takeuchi Institute for Electrochemically Stored Energy and Department of Materials Science and chemical Engineering Stony Brook UniversityStony BrookNew York 11794United States Department of chemical Engineering Columbia UniversityNew YorkNew York 10027United States Interdisciplinary Science Department Brookhaven National LaboratoryUptonNew York 11973United States

cONSPEcTUS:The demand for lithium ion batteries continues to expand for powering applications such as portable electronics,grid-scale energy storage,and electric *** the application requirements advance,the innovation of lithium ion batteries toward higher energy density and power output is *** with the investigation of new materials,an important strategy for increasing battery energy content is to design electrodes with high areal loading to minimize the fraction of nonactive materials such as current collectors,separators,and packaging components,resulting in significant gains in energy content and the reduction of the system-level ***,the adoption of thick high areal loading electrodes has been impeded by sluggish charge transport and mechanical *** conventional slurry cast electrodes,battery function significantly deteriorates with increases in electrode thickness due to high cell polarization and the incomplete utilization of active ***,a consideration of approaches that facilitate an understanding and eventual adoption of high-loading electrodes is warranted to enable the deliberate advancement of next-generation batteries.

关键词： battery lithium Electron

Adaptive load forecasting of the Hellenic electric grid

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第12期9卷 1724-1730页

作者： S.Sp.PAPPAS L.EKONOMOU V.c.MOUSSAS P.KARAMPELAS S.K.KATSIKAS Department of Information and communication Systems Engineering University of the AegeanSamos 83200 Greece Information Technology Faculty Hellenic American UniversityAthens 10680Greece School of Technological Applications Technological Educational Institute of AthensEgaleo 12210Greece Department of Technology Education and Digital Systems University of PiraeusPiraeus 18532Greece

Designers are required to plan for future expansion and also to estimate the grid's future utilization. This means that an effective modeling and forecasting technique, which will use efficiently the information contained in the available data, is required, so that important data properties can be extracted and projected into the future. This study proposes an adaptive method based on the multi-model partitioning algorithm (MMPA), for short-term electricity load forecasting using real data. The grid's utilization is initially modeled using a multiplicative seasonal ARIMA (autoregressive integrated moving average) model. The proposed method uses past data to learn and model the normal periodic behavior of the electric grid. Either ARMA (autoregressive moving average) or state-space models can be used for the load pattern modeling. Load anomalies such as unexpected peaks that may appear during the summer or unexpected faults (blackouts) are also modeled. If the load pattern does not match the normal be-havior of the load, an anomaly is detected and, furthermore, when the pattern matches a known case of anomaly, the type of anomaly is identified. Real data were used and real cases were tested based on the measurement loads of the Hellenic Public Power cooperation S.A., Athens, Greece. The applied adaptive multi-model filtering algorithm identifies successfully both normal periodic behavior and any unusual activity of the electric grid. The performance of the proposed method is also compared to that produced by the ARIMA model.

关键词： Adaptive multi-model filtering ARIMA Load forecasting Measurements Kalman filter Order selection Seasonalvariation Parameter estimation