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考试与评价（英语高考专刊） 2018年第3期 46-47页

作者： Sue peterson 宋伟杰

Geotechnical risk management to prevent coal outburst in room-and-pillar mining

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International Journal of Mining Science and Technology 2016年第1期26卷 9-18页

作者： zhang peter peterson scott neilans dan wade scott mc grady ryan pugh joe Alpha Natural Resources Inc. Waynesburg 15370 USA

A coal outburst is a severe safety hazard in room-and-pillar mining under deep cover. It is more likely to occur during pillar retreating. Multi-seam mining dramatically increases the risk of coal outburst within the influence zones created by remnant pillars and gob-solid boundaries. Though coal outburst is generally associated with heavy loading of coal pillars,its occurrence is difficult to predict. Risk management provides a proactive tool to minimize coal outburst in room-and-pillar mining under deep cover. Risk assessment is the first step in identifying and quantifying outburst risk factors. The primary risk factors for coal outburst are overburden depth,roof and floor strength,geological anomalies,mining type,multi-seam mining,and panel width. A risk assessment chart can be used to proactively screen out mining sections with high risk of coal outburst for further analysis. Gob-solid boundaries and remnant pillars are critical factors in evaluation of the coal outburst risk of multi-seam mining. Risk identification,risk assessment,geologic influence mapping,geotechnical evaluation,risk analysis,risk mitigation,and monitoring are essential elements of coal outburst risk management process. Training is an integral part of risk management for risk identification and communication between all the stakeholders including management,technical and safety personnel,and miners.

关键词： Coal outburstPillar retreatingPillar stabilityRisk management

Variation of Hyporheic Temperature Profiles in a Low Gradient Third-Order Agricultural Stream—A Statistical Approach

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Open Journal of Modern Hydrology 2013年第2期3卷 55-66页

作者： Vanessa Beach Eric W. peterson Department of Geography-Geology Illinois State University Normal USA.

Sediment size governs advection, controlling the hydraulic conductivity of the stratum, and conduction, influencing the amount of surface area in contact between the sediment particles. To understand the role of sediment particle size on thermal profiles within the hyporheic zone, a statistical approach, involving general summary statistics and time series cross-correlation, was employed. Data were collected along two riffles: Site 1: gravel (d50 = 3.9 mm) and Site 2: sand (d50 =0.94 mm).Temperature probe grids collected 15-minute temperature data at 30, 60, 90, and140cm below the streambed surface over a 6 month period. Surface water and air temperature were recorded. Diel temperature signal penetration depth was limited to the upper 30cm of the streambed and was driven by advection. Surface seasonal trends were detected at greater depths, indicating that thermal pulses are transmitted initially by advection and by conduction to areas deeper in the hyporheic zone. Site 1 showed a high degree of thermal heterogeneity via a localized downwelling zone within a gaining stream environment. Site 2 exhibited a vertically and horizontally homogenized thermal environment attributed to an increased amount of sand sediments that limited advection and significant groundwater discharge that mediated the effects of downwelling surface water.

关键词： Hyporheic Zone Temperature Time Series Analysis Cross-Correlation

Proton dynamics in phosphotungstic acid impregnated mesoporous silica proton exchange membrane materials

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Green Energy & Environment 2017年第3期2卷 294-301页

作者： Krystina Lamb Richard A.Mole Dehong Yu Roland de Marco John R Bartlett Sarah Windsor San Ping Jiang Jin Zhang Vanessa K.peterson Faculty of Science.Health Education and EngineeringUniversity of the Sunshine Coast Australian Centre for Neutron Scattering Australian Nuclear Science and Technology Organisation School of Chemistry and Molecular Biosciences The University of Queensland Fuels and Energy Technology Institute Curtin University

Phosphotungstic acid is an excellent proton conductor that can be incorporated into porous supports, and nanocomposite proton exchange membrane materials made from mesoporous silica impregnated with phosphotungstic acid have been suggested for use in fuels cells operating> 100 ℃. In this work, quasielastic neutron scattering was used to study proton self-diffusion in mesoporous disordered and P6 mm symmetry silica impregnated with two concentrations of phosphotungstic acid. Overall, the silica structure had a significantly greater effect on proton conduction and diffusion than phosphotungstic acid concentration, with higher proton conduction occurring for the P6 mm symmetry silica samples. Quasielastic neutron scattering revealed two populations of protons diffusing through each sample, and that proton conduction is limited by the slower of these populations, which diffuse via a jump-diffusion mechanism. Whilst the fundamental jump-diffusion mechanism by which these slower protons moved was found to be similar for both silica supports and phosphotungstic acid concentrations, the faster diffusion occurring in P6 mm structured silica arises from a lower residence time of protons moving between sites in the jump-diffusion model, suggesting a lower energy barrier.

关键词： Fuel cells Neutron scattering Proton conduction Proton exchange membranes Silica

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氟盐冷却高温堆半实物仿真及初步测试

原子能科学技术 2018年第4期52卷 659-665页

作者：阮见邹杨 KENDRICK J 李明海 peterson P F 徐洪杰中国科学院上海应用物理研究所上海201800 中国科学院大学北京100049 University of California Berkeley CA94706USA

基于半实物仿真理论,完善了氟盐冷却高温堆设计Mark-1的缩比模型CIET装置的功能,使该装置更能反映出反应堆运行的特点。借助MATLAB与LabVIEW的串口通信功能,在该装置的控制系统中增加中子动力学模型、反应性反馈模型以及温度控制和功率... 详细信息

基于半实物仿真理论,完善了氟盐冷却高温堆设计Mark-1的缩比模型CIET装置的功能,使该装置更能反映出反应堆运行的特点。借助MATLAB与LabVIEW的串口通信功能,在该装置的控制系统中增加中子动力学模型、反应性反馈模型以及温度控制和功率控制模型,使该装置能模拟Mark-1设计的一回路的运行。温度控制实验的测试结果显示,实验装置的加热器能迅速响应控制器的输出,达到设定的目标温度;通过对点堆功率控制模型的PID参数优化,获得较好的功率控制参数和调控结果,为后续优化控制逻辑、研究参数不确定性影响等奠定基础。

关键词：氟盐冷却高温堆半实物仿真串口通信控制逻辑

Integrative behavioral ecotoxicology： bringing together fields to establish new insight to behavioral ecology, toxicology, and conservation

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Current Zoology 2017年第2期63卷 185-194页

作者： Elizabeth K. peterson David B. BUCHWALTER Jacob L. KERBY Matthew K. LEFAUVE Claire W. VARIAN-RAMOS John R SWADDLE Department of Biological Sciences State University of New York-Albany Albany NY 12222 USA Department of Biological Sciences North Carolina State University Raleigh NC 27695 USA Department of Biology University of South Dakota Vermillion SD 57069 USA Department of Biological Sciences George Washington University Washington DC 20052 USA Department of Biology Colorado State University-Pueblo Pueblo CO 81001 USA Biology Department Institute for Integrative Bird Behavior Studies College of William & Mary Williamsburg VA 23187-8795 USA

The fields of behavioral ecology, conservation science, and environmental toxicology individually aim to protect and manage the conservation of wildlife in response to anthropogenic stressors, including widespread anthropogenic pollution. Although great emphasis in the field of toxicology has been placed on understanding how single pollutants affect survival, a comprehensive, interdis- ciplinary approach that includes behavioral ecology is essential to address how anthropogenic compounds are a risk for the survival of species and populations in an increasingly polluted world. We provide an integrative framework for behavioral ecotoxicology using Tinbergen＇s four postu- lates （causation and mechanism, development and ontogeny, function and fitness, and evolution- ary history and phylogenetic patterns）. The aims of this review are： 1） to promote an integrative view and re-define the field of integrative behavioral ecotoxicology; 2） to demonstrate how study- ing ecotoxicology can promote behavior research; and 3） to identify areas of behavioral ecotoxicol- ogy that require further attention to promote the integration and growth of the field.

关键词： animal behavior behavioral ecology conservation phylogenetic pollution toxicology.

The Effects of 5 Weeks of Leg-Drive Training on Bench Press Performance in Recreationally-Trained,College-Age Men

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Journal of Science in Sport and Exercise 2022年第3期4卷 231-236页

作者： Jacob K.Gardner Justin T.Chia Brent M.peterson Kelsey L.Miller Department of Kinesiology and Health Science Biola University13800 Biola AveLa MiradaCA 90639USA Department of Health and Human Development Western Washington University516 High StreetBellinghamWA 98225USA

Introduction The bench press is commonly used to measure upper-body *** much emphasis has been placed on the upper-body,little is known about how the lower-body can play a role in bench press ***-drive is a technique that includes flexing the knee so the feet line up posterior to the knee joint,while simultaneously contracting the knee extensors isometrically during the *** purpose of this study was to compare strength characteristics of lifters in a standard bench press versus a leg-drive bench press over the course of 5-weeks of *** Twenty-three recreationally active males(age:22.4±2.1 years,height:175.0±5.9 cm,mass:78.4±9.5 kg)were randomized into a standard bench or leg-drive bench press *** performed four sets to failure,two times per week for five *** of interests were training volume and 1-repetition maximum(1RM)*** training volume,a 2×5(group×week)repeated measures analysis of variance(RMANOVA)was *** the 1RM’s,a 2×2×2(group×press type×time)RMANOVA was used.A priori alpha levels were set to *** Over time,both groups showed an approximate 6%increase in 1RM *** volume for week 4 was 5.6%less than week 5,but was not different from weeks 1 through *** between-group differences were observed for 1RM strength or training *** This results of this work indicates that 5 weeks of leg-drive training is effective in increasing 1RM strength,but was not more effective than standard bench press ***,lifters should choose either lifting style based on personal preference.

关键词： Chest press Lower-body Weight lifting Isometric contraction

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穇属颖果微形态及其系统学意义

热带亚热带植物学报 2011年第3期19卷 195-204页

作者：姜斌 Paul M.peterson 刘青中国科学院华南植物园中国科学院植物资源保护与可持续利用重点实验室广州510650 中国科学院研究生院北京100049 Department of Botany Smithsonian InstitutionWashington DC 20013-7012USA

在电子扫描显微镜下观察了穇属(Eleusine Gaertn.)9种植物颖果的微形态特征。结果表明,穇属颖果有卵形、披针形和矩圆形3种腹面形状,压扁方式有背腹压扁及两侧压扁,腹面形态有平腹面和凹腹面两种,胚比为0.29～0.58,种脐比为0.10～0.24,... 详细信息

在电子扫描显微镜下观察了穇属(Eleusine Gaertn.)9种植物颖果的微形态特征。结果表明,穇属颖果有卵形、披针形和矩圆形3种腹面形状,压扁方式有背腹压扁及两侧压扁,腹面形态有平腹面和凹腹面两种,胚比为0.29～0.58,种脐比为0.10～0.24,颖果纹饰有2种,包括疣突状一级纹饰和疣突规则排列构成的复合网状(二级)纹饰,表面小孔平均直径0.57～1.31μm,分布密度为30～200个(100μm-2)。穇属植物的颖果腹面形状、纹饰、表面小孔直径及平均密度等性状,可为种类鉴定及种间关系分析提供有价值的证据。穇属颖果腹面形态呈平腹面或凹腹面,颖果体积相对小,生活周期相对缩短,这可能是与东非季节性干旱气候相适应的。

关键词：穇属颖果微形态分类禾本科

Outcomes and impact of an advanced clinical ultrasound track in an emergency medicine residency

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World Journal of Emergency Medicine 2024年第6期15卷 486-489页

作者： Charles W.Kropf David A.Haidar Ryan V.Tucker William peterson Neil Khanna Rob D.Huang Christopher M.Fung Nik Theyyunni Department of Emergency Medicine University of Michigan Medical SchoolMichigan 48109USA Department of Emergency Medicine University of ColoradoColorado 80045USA Department of Emergency Medicine Henry Ford Health SystemMichigan 48109USA

Point-of-care ultrasound(POCUS)is a core component of emergency medicine(EM)residency training used to guide medical decision making and to enhance procedural competence.[1-3]Many repetitions of POCUS exams are required to achieve competency,and it is difficult to quantify a minimum needed to achieve mastery.[4,5]For EM residents whose career goals require greater depth of knowledge and skill in POCUS,educators can consider expanded training through a professional development track.

关键词： repetition expanded impact

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霍耳-埃鲁电解槽冰晶石熔体中氟化锂的损失

轻金属 1989年第6期 35-40,64页

作者： RayD.peterson 肖海明

导言铝电解工业采用氟化锂改良电解质不是什么新创举。实际上,Charles Hall在他早先的专利中对使用氟化锂作了一般性的申述。当今,已普遍公认氟化锂改良电解质具有所希望的性质。由于熔盐中锂离子迁移率高。

关键词：铝电解槽冰晶石熔体氟化锂