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论完整岩体的现场强度

岩石力学与工程学报 2014年第1期33卷 1-13页

作者：蔡明赵星光 KAISER p K 劳伦森大学工程学院核工业北京地质研究院北京100029 卓越开采创新中心

目前国际上普遍认为完整岩体的现场强度近似等于(0.4?0.1)?c,其中,?c为室内岩石单轴抗压强度。此外,也有学者建议原位岩体的破坏强度,即地下工程围岩的启裂强度,可等价于室内单轴压缩试验或现场微震监测确定的岩石裂隙初始的应力;其原... 详细信息

目前国际上普遍认为完整岩体的现场强度近似等于(0.4?0.1)?c,其中,?c为室内岩石单轴抗压强度。此外,也有学者建议原位岩体的破坏强度,即地下工程围岩的启裂强度,可等价于室内单轴压缩试验或现场微震监测确定的岩石裂隙初始的应力;其原理主要以基于Kirsch解析解或简化的数值模拟(光滑的开挖边界)来近似表达隧道开挖面上的最大切向应力?max。然而,这些方法均忽略了开挖边界的几何非规则性对计算结果的影响。经论证表明,若考虑开挖面的几何非规则性因素,完整岩体的现场破坏强度并不等于(0.4?0.1)?c,其破坏强度可高达(0.8?0.05)?c。以加拿大地下实验室Mine-by试验隧道为例,并以该隧道的实际断面形状为几何边界条件,采用有限元软件phase 2模拟隧道围岩的渐进破坏过程。研究结果表明,当原位岩体强度为0.8?c时,模拟结果与实际观测结果具有很好的一致性。因此,忽略开挖边界的几何非规则性而解读的原位岩体强度(0.4?0.1)?c仅是"等价"强度值,其低估了岩体的实际强度。

关键词：岩石力学岩石强度等价岩体强度实际岩体强度裂隙初始劈裂破坏非规则开挖边界脆性岩石

Effect of Fluctuating Temperatures on Forest SoilNitrogen Mineralization

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pedosphere 1997年第1期7卷 31-34页

作者： LIAOLIpING p．INESON InstituteofAppliedEcology ChineseAcademyofSciecesShenyang110015（China） InstituteofTerrestrialEcology

Nitrogen mineralization in forest soil was studied in laboratory by incubating undisturbed soil cores enclosed within pVC columns at different temperatures to compare the effect of fluctuating temperature with that of constant temperature, and to find out whether soil nitrification shows linearity over time. The results showed that there was no significant difference between soil nitrification at fluctuating temperature and that at constant temperature, and suggested that it must be careful to make the conclusion that soil nitrification has linearity over time.

关键词： fluctuating temperature linearity nitrogen mineralization

Asymptotic Behavior of Forced Nonlinear Delay Differential Equations with Impulses

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Acta Mathematica Sinica,English Series 2000年第4期16卷 565-572页

作者： Jiaowan Luo Institute of Sciences. Changsha Railway University. Changsha 410075. p. R. China Jianhua Shen Department of Mathematics. Hunan Normal University. Changsha 410081. p. R. China Institute of Sciences Changsha Railway University Changsha 410075 P. R. China Department of Mathematics Hunan Normal University Changsha 410081 P. R. China

The purpose of this paper is to investigate the asymptotic behavior of solutions of the forced nonlinear delay differential equations with impulses x’(t)+sum from i=1 to n(p_i(t)f(x(t-т_i))=h(t)). t≠t_k, x(t_k^+)-x(t_k)=b_kx(t_k). Our results. which hold for linear and nonlinear equations, forced and unforced equations, impulsive and nonimpulsive equations. improve and generalize the known results recently obtained in [8].

关键词： Asymptotic behavior Delay differential equation Impulsive perturbation

Electro-Hydrodynamics and Kinetic Modeling of Dry and Humid Air Flows Activated by Corona Discharges

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plasma Science and Technology 2016年第5期18卷 469-472页

作者： J. p. SARRETTE O. EICHWALD F. MARCHAL O. DUCASSE M. YOUSFI CNRS LAPLACE Toulouse F-31062 France Universite de Toulouse UPS INPTLAPLXCE (Laboratoire Plasma et Conversion d'Energie) Toulouse Cedex 9 F-31062 France

The present work is devoted to the 2D simulation of a point-to-plane Atmospheric Corona Discharge Reactor （ACDR） powered by a DC high voltage supply. The corona reactor is periodically crossed by thin mono filamentary streamers with a natural repetition frequency of some tens of kHz. The study compares the results obtained in dry air and in air mixed with a small amount of water vapour （humid air）. The simulation involves the electro-dynamics~ chemical kinetics and neutral gas hydrodynamics phenomena that influence the kinetics of the chemical species transformation. Each discharge lasts about one hundred of a nanosecond while the post- discharge occurring between two successive discharges lasts one hundred of a microsecond. The ACDR is crossed by a lateral dry or humid air flow initially polluted with 400 ppm of NO. After 5 ms, the time corresponding to the occurrence of 50 successive discharge/post-discharge phases, a higher NO removal rate and a lower ozone production rate are found in humid air. This change is due to the presence of the HO2 species formed from the H primary radical in the discharge zone.

关键词： DC corona discharge humid air chemistry plasma simulation NO treatment

projection of the Semi-Axes of the Ellipse of Intersection

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Applied Mathematics 2017年第9期8卷 1320-1335页

作者： p. p. Klein Computing Center University of Technology Clausthal Clausthal-Zellerfeld Germany

It is well known that the line of intersection of an ellipsoid and a plane is an ellipse (see for instance [1]). In this note the semi-axes of the ellipse of intersection will be projected from 3d space onto a 2d plane. It is shown that the projected semi-axes agree with results of a method used by Bektas [2] and also with results obtained by Schrantz [3].

关键词： Ellipsoid and plane Intersection projection of the Semi-Axes of the Ellipse of Intersection

NUMERICAL SIMULATION ON FORMING pROCESS OF EAR pORTION OF UppER CASE

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中国有色金属学会会刊：英文版 1998年第4期8卷 71-74页

作者： Hao Nanhai, Xue Kemin and L Yan Department of Metal Forming, Taiyuan Heavy Machinery Institute, Taiyuan 030024, p. R. China School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, p. R. China Department of Metal Forming Taiyuan Heavy Machinery Institute Taiyuan 030024 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

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１ＩＮＴＲＯＤＵＣＴＩＯＮＵｐｐｅｒｃａｓｅｉｓａｋｅｙｐａｒｔｉｎｔｈｅｄｒｉｖｉｎｇｓｙｓｔｅｍｏｆａｈｅｌｉｃｏｐｔｅｒ．ＴｈｅｕｐｐｅｒｃａｓｅｆｏｒｇｉｎｇｉｓｓｈｏｗｎｉｎＦｉｇ．１ａｎｄｉｔｓｍａｔｅｒｉａｌｉｓＭＢ１５ｍａｇｎｅｓ...

关键词： die forging finite element method upper case

Structure and regeneration status of mangrove patches along the estuarine and coastal stretches of Kerala, India

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Journal of Forestry Research 2019年第2期30卷 507-518页

作者： Grinson George p.Krishnan K.G.Mini S.S.Salim p.Ragavan S.Y.Tenjing R.MuruganANDam S.K.Dubey A.Gopalakrishnan R.purvaja R.Ramesh ICAR-Central Marine Fisheries Research Institute National Centre for Sustainable Coastal Management Ministry of EnvironmentForest and Climate Change Department of Aquatic Environment Management Faculty of Fishery Sciences West Bengal University of Animal and Fishery Sciences

This study presents the structural characteristics and regeneration potential of mangrove patches in the estuarine and coastal areas of Kerala, a tropical maritime state in India. Field surveys were carried out at 46 selected sites during August 2015 to May 2016. In each site, the vegetative structure and regeneration status were assessed using the quadrat method. Altogether 219 quadrates were laid out and a total of 13 true mangrove species, belonging to 5 families and 8 genera, were recorded. The total tree density and stand basal area of the study region was1678.08/ha and 20.33 m^2/ha respectively. The low basal areas indicate the reduced structural development in mangroves. Of the 13 tree species, Avicennia constitutes 56%of the total Important Value Index(IVI) and Avicennia officinalis represents 41% of the IVI in Kerala, followed by Avicennia marina(15%), Rhizophora mucronata(15%),Sonneratia alba(8%) Rhizophora apiculata(7%) and Excoecaria agallocha(7%). The diameter at breast height(DBH) in the study area revealed that 47% of the tree species came under the 1–10 cm DBH class. Total sapling and seedling density in Kerala was 2238.35 and 3232.42 individuals/ha respectively. Density of young plants(seedlings ? saplings) was only 31% greater of tree density and varied from 3–63%, which indicates poor regeneration potential. The Maturity index value(MIV) and complexity index(Ic) value of mangroves were 18.30 and 109.81 respectively. However, the low Ic value(\ 10) observed in seven out of ten coastal districts indicated poor structural development of mangroves in Kerala. Therefore, locationspecific conservation and management measures, guided by the knowledge on spatial distribution and habitat requirements of mangrove varieties should be taken to preserve the mangrove diversity of Kerala.

关键词： Tree density Complexity Quadrat survey Maritime Regeneration

3种高温合金的蠕变-疲劳交互作用行为及寿命预测

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金属学报 2006年第9期42卷 952-958页

作者：陈立佳吴崴 p.K.Liaw 沈阳工业大学材料科学与工程学院沈阳110023 Department of Materials Science and Engineering

通过在816和927℃下进行总应变控制的不同拉伸应变保持时间的低周疲劳实验,研究了3种高温合金(HAYNES 188,HAYNES 230和HASTELLOY X)的蠕变-疲劳交互作用行为．结果表明,这3种高温合金的应变疲劳寿命主要取决于合金类型、应变保持周期... 详细信息

通过在816和927℃下进行总应变控制的不同拉伸应变保持时间的低周疲劳实验,研究了3种高温合金(HAYNES 188,HAYNES 230和HASTELLOY X)的蠕变-疲劳交互作用行为．结果表明,这3种高温合金的应变疲劳寿命主要取决于合金类型、应变保持周期及实验温度．这些高温合金所表现出的不同应变疲劳寿命行为可归因于蠕变和氧化损伤方面的差异．此外,应用频率修正的非弹性拉伸应变能作为损伤函数对这3种合金进行了应变疲劳寿命预测,结果显示该寿命预测方法对3种高温合金均表现出较好的寿命预测能力．

关键词：高温合金蠕变-疲劳交互作用应力松弛寿命预测

plasma-Chemical Synthesis of Oxide powders Using Transformer-Coupled Discharge

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plasma Science and Technology 2013年第4期15卷 386-390页

作者： I. M. ULANOV M. V. ISUpOV A. Yu LITVINSEV p. A. MISCHENKO Kutateladze Institute of Thermophysics SB RAS Lavrentiev av.1Novosibirsk 630090 Russia Kutateladze Institute of Thermophysics SB RAS Lavrentiev av.1Novosibirsk 630090 Russia

An experimental investigation of transformer-coupled discharge in an Ar-O2 mixture with the addition of SICl4, TiCl4 and ZrCl4 has been carried out under the atmospheric pressure of plasma-forming gases. Discharge power and discharge heat losses have been determined, and the dispersion and phase composition of reaction products （oxide powders） has been analyzed with SEM and X-ray diffraction analysis. Investigations reveal the formation of ultrafine oxide powders in the case of vaporized chloride （SiCl4 and TiCl4） injecting into the transformer coupled discharge. In the case of fine powder （ZrCl4） injection, full oxidation was not observed and reaction products consisted of a mixture of ZrO2 and ZrOCl2. A conclusion has been made regarding the perspectives of using transformer-coupled discharge to produce ultrafine oxide powders.

关键词： inductively coupled plasma powders silicon dioxide zirconium dioxide tita-nium dioxide