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The glassy solid as a statistical ensemble of crystalline microstates

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npj Computational Materials 2020年第1期6卷 1199-1204页

作者： Eric b.jones Vladan Stevanović Colorado School of Mines GoldenCO 80401USA National Renewable Energy Laboratory GoldenCO 80401USA

We present an alternative and,for the purpose of non-crystalline materials design,a more suitable description of covalent and ionic glassy solids as statistical ensembles of crystalline local minima on the potential energy *** by the concept of partially broken ergodicity,we analytically formulate the set of approximations under which the structural features of ergodic systems such as the radial distribution function(RDF)and powder X-ray diffraction(XRD)intensity can be rigorously expressed as statistical ensemble averages over different local *** is carried out by evaluating these ensemble averages for elemental Si and SiO_(2) over the local minima obtained through the first-principles random structure sampling that we performed using relatively small simulation cells,thereby restricting the sampling to a set of predominantly crystalline *** comparison with XRD and RDF from experiments(amorphous silicon)and molecular dynamics simulations(glassy SiO_(2))shows excellent agreement,thus supporting the ensemble picture of glasses and opening the door to fully predictive description without the need for experimental inputs.

关键词： ensemble crystalline glasses

Modeling temperature and moisture dependent emissions of carbon dioxide and methane from drying dairy cow manure

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Frontiers of Agricultural Science and Engineering 2018年第2期5卷 280-286页

作者： Enzhu HU Pakorn SUTITARNNONTR Markus TULLER Scott b.jones Institute of Resources and Environmental Sciences School of Metallurgy Northeastern University Department of Plants Soils and Climate Utah State University Department of Soil Water and Environmental Science The University of Arizona

Greenhouse gas emissions due to biological degradation processes of animal wastes are significant sources of air pollution from agricultural areas. The major environmental controls on these microbe-induced gas fluxes are temperature and moisture content. The objective of this study was to model the effects of temperature and moisture content on emissions of CO2 and CH4 during the ambient drying process of dairy manure under controlled conditions. Gas emissions were continuously recorded over 15 d with paired fully automated closed dynamic chambers coupled with a Fourier Transformed Infrared gas analyzer. Water content and temperature were measured and monitored with capacitance sensors. In addition, on days 0, 3, 6, 9, 12 and 15, p H, moisture content, dissolved organic carbon and total carbon(TC) were determined. An empirical model derived from the Arrhenius equation confirmed high dependency of carbon emissions on temperature and moisture content. Results indicate that for the investigated dairy manure, 6.83% of TC was lost in the form of CO2 and 0.047% of TC was emitted as *** the effect of temperature, the moisture contents associated with maximum gas emissions were estimated as0.75 and 0.79 g$g–1 for CO2 and CH4, respectively.

关键词： carbon dioxide dairy manure methane moisture temperature

Electromagnetic induction mapping at varied soil moisture reveals field-scale soil textural patterns and gravel lenses

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Frontiers of Agricultural Science and Engineering 2017年第2期4卷 135-145页

作者： Hiruy AbDU David A.RObINSON Janis bOETTINGER Scott b.jones biological and Irrigation Engineering Department Utah State University Centre for Ecology & Hydrology Environment Centre Wales Plants Soils and Climate Department Utah State University

Knowledge of the spatial distribution of soil textural properties is important for determining soil moisture storage and soil hydraulic transport *** field heterogeneity without exhaustive sampling and costly sample analysis is difficult. Our objective was to employ electromagnetic induction(EMI) mapping in low apparent electrical conductivity(EC_a) soils at varying soil water contents to capture time invariant properties such as soil texture. Georeferenced EC_ameasurements were taken using a ground conductivity meter on six different days where volumetric water content(θ_v) varied from 0.11 to 0.23. The 50 m × 50 m field included a subsurface gravelly patch in an otherwise homogeneous silt-loam alluvial *** block kriging predicted EC_aat unsampled areas to produce 1-m resolution maps. Temporal stability analysis was used to divide the field into three distinct EC_a regions. Subsequent ground-truthing confirmed the lowest conductivity region correlated with coarse textured soil parent materials associated with a former high-energy alluvial depositional area. Combining maps using temporal stability analysis gives the clearest image of the textural difference. These maps could be informative for modeling,experimental design, sensor placement and targeted zone management strategies in soil science, ecology, hydrology,and agricultural applications.

关键词： soil electrical conductivity soil texture mapping temporal stability analysis

阿尔伯达山脚地区东倾俯冲断层下的石油与天然气

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新疆石油地质 1990年第3期11卷 177-198页

作者： Peter b.jones

在阿尔伯达地区,科迪勒拉造山带前陆边缘的大部分地区是以一系列东倾俯冲断层为标志的,这些俯冲断层上覆于人们更为熟识的西倾山脚叠瓦逆冲断裂构造。13000km^2的山脚地区,包括很多主要的油气田在内,都封闭于俯冲断层带之下,这个俯冲断... 详细信息

在阿尔伯达地区,科迪勒拉造山带前陆边缘的大部分地区是以一系列东倾俯冲断层为标志的,这些俯冲断层上覆于人们更为熟识的西倾山脚叠瓦逆冲断裂构造。13000km^2的山脚地区,包括很多主要的油气田在内,都封闭于俯冲断层带之下,这个俯冲断层带是曾经覆盖着科迪勒拉东部更广大地区的一个硕部滑脱带经剥蚀后的残迹。沿顶部滑脱带的两边相对出露的东倾和西倾地层并排延伸便形成了一个长达数百千米、被称之为“前缘褶皱”或“三角带”的伪背斜。“三角带”的地下地质看起来很混乱,其实它可以看成是由叠覆的逆掩冲断席的系统排列而成。这些逆掩冲断席由于阶梯断裂而被褶皱并与顶部滑脱带合并,项部滑脱带本身又由于其下的构造增厚而被褶皱。众所周知,落基山山脚地带和前缘山岭的西倾叠瓦逆冲断层是以一底部断层或称底部滑脱断层为根的。“三角带”的几何形态证明还存在一顶部滑脱带。顸部和底部滑脱带在阿尔伯达向斜的轴部合并,从而标志了山脚地区构造形变的东部边界。其他逆掩冲断带的前陆边缘的横剖面也表明俯冲边缘是普遍的,而且“三角带”几何形态和地质原理可以解释一些普遍的构造异常。

关键词：石油天然气俯冲断层

Investigation of Compressible Electromagnetic Flute Mode Instability in Finite beta Plasma in Support of Z-pinch and Laboratory Astrophysics Experiments

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Communications in Computational Physics 2008年第8期4卷 611-623页

作者： V.I.Sotnikov V.V.Ivanov R.Presura J.N.Leboeuf O.G.Onishchenko b.V.Oliver b.jones T.A.Mehlhorn C.Deeney University of Nevada at Reno NV 89523USA JNL Scientific Casa GrandeAZ 85222USA Institute of Physics of Earth 123995MoscowRussia Sandia National Laboratories NM 87123USA Department of Energy WashingtonDC 20585USA

Flute mode turbulence plays an important role in numerous applications,such as tokamak,Z-pinch,space and astrophysical *** a low beta plasma flute oscillations are electrostatic and in the nonlinear stage they produce large scale density structures co-mingling with short scale *** scale structures are responsible for the enhanced transport across the magnetic field and appearance of short scales leads to ion heating,associated with the ion *** the present paper nonlinear equations which describe the nonlinear evolution of the flute modes treated as compressible electromagnetic oscillations in a finite beta inhomogeneous plasma with nonuniform magnetic field are derived and solved *** this purpose the 2D numerical code FLUTE was *** results show that even in a finite beta plasma flute mode instability can develop along with formation of large scale structures co-existing with short scale perturbations in the nonlinear stage.

关键词： Flute instability plasma turbulence nonlinear cascades

Oral epithelial stem cells in tissue maintenance and disease: the first steps in a long journey

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International Journal of Oral Science 2013年第3期5卷 121-129页

作者： Kyle b.jones Ophir D Klein Program in Craniofacial and Mesenchymal biology University of California Division of Medical Genetics Department of PediatricsUniversity of California Center for Craniofacial Anomalies Department of Orofacial Sciences University of California

The identification and characterization of stem cells is a major focus of developmental biology and regenerative *** advent of genetic inducible fate mapping techniques has made it possible to precisely label specific cell populations and to follow their progeny over *** combined with advanced mathematical and statistical methods,stem cell division dynamics can be studied in new and exciting *** advances in a number of tissues,relatively little attention has been paid to stem cells in the oral *** review will focus on current knowledge about adult oral epithelial stem cells,paradigms in other epithelial stem cell systems that could facilitate new discoveries in this area and the potential roles of epithelial stem cells in oral disease.

关键词： cancer stem cell invariant asymmetry neutral drift oral epithelial stem cell population asymmetry

Carbon dioxide conversion to valuable chemical products over composite catalytic systems

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Journal of Energy Chemistry 2013年第3期22卷 368-374页

作者： Robert A.Dagle Jianli Hu Susanne b.jones Wayne Wilcox John G.Frye James F.White Juyuan Jiang Yong Wang Pacific Northwest National Laboratory RichlandWA 99352USA School of Automation Engineering Tianjin University of Technology Pacific Northwest National Laboratory.Richland WA 99352USA Voiland School of Chemical Engineering and bioengineering Washington State University

This paper reports an experimental study on catalytic conversion of carbon dioxide to methanol, ethanol and acetic acid. Satalysts having different catalytic functions were synthesized and combined in different ways to enhance the selectivity to desired products. The combined catalyst system possessed the following functions： methanol synthesis, Fischer-Tropsch synthesis, water-gas-shift and hydrogenation. Results showed that the methods of integrating these catalytic functions played an important role in achieving the desired product selectivity. We speculate that if methanol synthesis sites were located adjacent to the C--C chain growth sites, the formation rate of C2 oxygenates would be enhanced. The advantage of using a high temperature methanol catalyst PdZnA1 in the combined catalyst system was demonstrated. In the presence of PdZnA1 catalyst, the combined catalyst system was stable at 380 ~C. It was observed that, at high temperature, kinetics favored oxygenate formation. The results implied that the process can be intensified by operating at high temperature using Pd-based methanol synthesis catalyst. Steam reforming of the byproduct organics was demonstrated as a means to provide supplemental hydrogen. Preliminary process design, simulation, and economic analysis of the proposed CO2 conversion process were carded out. Economic analysis indicates how ethanol production cost was affected by the price of CO2 and hydrogen.

关键词： CO2 utilization syngas Fischer-Tropsch methanol higher alchohols ethanol acetic acid

关于哥伦比亚东安第斯山地球动力学演化的另外一种假设

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国外油气勘探 2000年第4期12卷 383-394页

作者： Peter b.jones 吕明石油大学(北京)盆地与油藏研究中心

对于哥伦比亚安第斯山的东科迪勒拉山脉中新世一上新世的构造演化,最近有一些假设,这些假设提出了一个发散的扇形模式,该模式把科迪勒拉山脉东边的南东倾基底冲断系统与西边西北倾基底冲断系统联系起来。然而,西部冲断系统的构造关系表... 详细信息

对于哥伦比亚安第斯山的东科迪勒拉山脉中新世一上新世的构造演化,最近有一些假设,这些假设提出了一个发散的扇形模式,该模式把科迪勒拉山脉东边的南东倾基底冲断系统与西边西北倾基底冲断系统联系起来。然而,西部冲断系统的构造关系表明,其断层是由造山运动后的地表重力驱动所致。这就形成了关于哥伦比亚安第斯山演化的另外一种假设,它对于油气勘探具有构造、地层和地温等方面的意义。在这个新模式里,东科迪勒拉山脉和Perija安第斯山被认为是单个南东倾掩冲席的一部分,并具有小型叠瓦构造。起初,作为具有三角带(埋藏的冲断层前缘)几何形状隐伏掩冲席,它向南东东方向运动,形成了东科迪勒拉山脉、Santandar地块、Perija安第斯山的持续抬升区域。由于下部梅瑞达(Merida)安第斯山冲断系统的侵位作用,掩冲席形成"猪背状",进一步向南东方向迁移至目前的位置,总共缩短约185km。根据这个新模式,这个掩冲席的原始前缘被一个倾斜的侧向断坡错开。变形之后,下盘内所有的侧面阶梯都被掩冲席内的正断层运动所接纳,形成bucaramanga断层,具有210km明显的走向滑移错距。

关键词：冲断层掩冲层地球动力学安第斯山

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土壤特性与地三叶一禾草草地生产的关系

草学 1984年第4期 83-88页

作者： MILTON b.jones 侯发远四川省草原研究所

在加利福尼亚西北部,水分通常不是冬春草地生产的限制因素。因而,弄清其它生境因素（物理、化学因素）如何影响草地生产是很重要的。运用Ridge回归分析和单相关评价草地生产与草场坡度、海拔、土层厚度、土壤质地及其容重,持水量、pH和... 详细信息

在加利福尼亚西北部,水分通常不是冬春草地生产的限制因素。因而,弄清其它生境因素（物理、化学因素）如何影响草地生产是很重要的。运用Ridge回归分析和单相关评价草地生产与草场坡度、海拔、土层厚度、土壤质地及其容重,持水量、pH和肥力（包括有效磷、硫、交换性阳离子、全氮、全硫和有机质）的关系。对17个典型草场的4种施肥处理（P0S0,P300S0,P0S90,P300S90）进行地三叶—禾草产量测定。不施肥时,土壤pH和有效磷看来是与产草量关系最密切的两个变量。施磷和硫时,产草量增加。单施磷时,土壤交换性钾与产草量关系最密切;而单施硫时,有效磷与产草量关系最密切。当磷、硫配合施用时,土壤有效磷和有效钾与产草量密切相关。一般说来,施硫对牧草产量有显著的效应,然而本试验表明,土壤有效硫却与产草量相关性不强。

关键词：交换性钾产草量禾草有效硫草地土壤特性有效磷速效磷全硫