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Limit equilibrium method(LEM) of slope stability.and calculation of comprehensive factor of safety.with double strength-reduction technique

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Journal of Mountain Science 2017年第11期14卷 2311-2324页

作者： DENG dong-ping LI Liang ZHAO Lian-heng School of Civil Engineering Central South University

When the slope is in critical limit equilibrium(LE) state, the strength parameters have different contribution to each other on maintaining slope stability. That is to say.that the strength parameters are not simultaneously.reduced. Hence, the LE stress method is established to analy.e the slope stability.by.employ.ng the double strengthreduction(DSR) technique in this work. For calculation model of slope stability.under the DSR technique, the general nonlinear Mohr–Coulomb(M–C) criterion is used to describe the shear failure of slope. Meanwhile, the average and polar diameter methods via the DSR technique are both adopted to calculate the comprehensive factor of safety.FOS) of slope. To extend the application of the polar diameter method, the original method is improved in the proposed method. After comparison and analy.is on some slope examples, the proposed method's feasibility.is verified. Thereafter, the stability.charts of slope suitable for engineering application are drawn. Moreover, the studies show that:(1) the average method y.elds similar results as that of the polardiameter method;(2) compared with the traditional uniform strength-reduction(USR) technique, the slope stability.obtained using the DSR techniquetends to be more unsafe; and(3) for a slope in the critical LE state, the strength parameter φ, i.e., internal friction angle, has greater contribution on the slope stability.than the strength parameters c, i.e., cohesion.

关键词： Slope stability Nonlinear Mohr-Coulomb (M-C) criterion Double strength-reduction(DSR) technique Slope Comprehensive Factor ofSafety (FOS) Stability charts

Aeolian transport over a developing transverse dune

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Journal of Arid Land 2014年第3期6卷 243-254页

作者： ZhiBao dong ping LV ZhengCai ZHANG JunFeng LU Key.Laboratory.of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

The spatial and temporal changes in aeolian transport over a dune are fundamental factors that control the morphology.of the dune. In the present study. we obtained direct field observations of aeolian transport over a developing transverse dune at the Shapotou Aeolian Experiment Site in the southeastern part of China＇s Tengger Desert. The transport rate versus wind speed relationship relationships over flat surfaces and over dunes that are s complicated over a developing dune compared with the n equilibrium with the wind. We obtained trend lines for transport rate over the transverse dune versus distance. The transport rate generally.increased from the toe to the crest above the stoss slope, but the difference in transport rate between the crest and the toe was smaller than those that have been proposed for taller dunes. The crest/toe ratio for transport rates therefore seems to depend greatly.on dune height. Flux density.profiles for different points above the dune at different wind speeds were well described by.the exponential decay.law, as has been proposed for saltation flux density.profiles. Coefficients in the flux density.profile function can be defined in terms of the transport rate and wind speed. However, the dependence of relative decay.rate with height and average saltation height on wind speed was weaker than that observed in a wind tunnel and above a fiat surface. The preliminary.results obtained in this study.require more evidence from field observations to fully.describe aeolian transport above developing dunes.

关键词： aeolian transport aeolian geomorphology dune dy.amics

3D Modeling of the preparation process of metal rubber material

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International Journal of Minerals,Metallurgy.and Materials 2010年第1期17卷 75-79页

作者： Ming-ji Huang Xiu-ping dong Guo-quan Liu School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China School of Mechanical Engineering Beijing Technology and Business University Beijing 100048 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Based on the analy.is of the preparation of metal rubber （MR） and two pivotal hy.otheses, the uniform distribution and the unaltered topological structure of wires in the radial direction of columns in the punch process, a 3D parametrical model was established based on four approaches： helix-making, planar roughcast-weaving, planar roughcast-rolling, and 3D roughcast punching. In the modeling process, 5 lattice ty.es of weave patterns in planar roughcast were put forward, and 10 quantificational modeling parameters were picked up to exclusively.define the column MR component structure. The wire distribution was visualized by.CAD techniques. The important performance parameter of column MR components （relative density.ρ^- ） can be forecasted by.modeling computing, which provides the necessary.foundation for the design and optimization of MR materials.

关键词： metal rubber preparation process weaving parametric model

Association between Helicobacter py.ori infection and food-specific immunoglobulin G in Southwest China

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World Journal of Clinical Cases 2021年第32期9卷 9815-9824页

作者： y.ng Liu ping Shuai y.-ping Liu dong-y. Li Health Management Center Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 611731Sichuan ProvinceChina Health Management Center Chinese Academy of Sciences Sichuan Translational Medicine Research HospitalChengdu 610072Sichuan ProvinceChina

BACKGROUND Helicobacter py.ori(***)has been found to be associated with extragastrointestinal diseases,possibly.including adverse food reactions(such as food allergy.or intolerance).However,there are few studies on *** and food allergy.or intolerance,and the results are ***-specific immunoglobulin(Ig)G has been revealed to be associated with food allergy.or intolerance and can be used as a marker to explore the correlation between *** infection and food allergy.or *** To explore the relationship between *** infection and food-specific IgG METHODS We retrospectively.analy.ed the phy.ical examination data of 21822 subjects from February.2014 to December 2018 in this *** infection was detected using the 13C urea breath ***-specific IgG of eggs,milk and wheat in serum was *** were grouped according to *** positivity.and the positive rates of three kinds of food-specific IgG were compared between the two *** logistic regression analy.is was performed to elucidate the association between *** infection and food-specific *** The total infection rate of *** was 39.3%,and the total food-specific IgGpositive rates of eggs,milk and wheat were 25.2%,9.0%and 4.9%,*** infection rate of *** was higher in males than in females,while the positive rates of food-specific IgG were lower in males than in *** positive rates of food-specific IgG decreased with age in both males and *** the ***-positive groups,the positive rates of food-specific IgG of eggs,milk and wheat were all lower than those in the ***-negative *** logistic regression analy.is revealed that *** infection was negatively.correlated with the food-specific IgG-positive rates of eggs,milk and wheat(odds ratio value of eggs 0.844-0.873,milk 0.741-0.751 and wheat 0.755-0.788,in different models).CONCLUSION *** infection was found to be negati

关键词： Food-specific IgG Helicobacter py.ori Adverse food reaction Food allergy Food intolerance Humoral immunity

Poly.er hy.rogel confined palladium nanoparticles as recy.lable cataly.ts for Suzuki and Heck cross-coupling reactions

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Chinese Chemical Letters 2020年第6期31卷 1630-1634页

作者： Kan Zhan ping Lu Jian dong Xu Hou School of Chemistry.and Chemical Engineering Shaoxing UniversityShaoxing 312000China School of Chemistry.and Chemical Engineering Xiamen UniversityXiamen 361005China

Reusable palladium nanoparticles highly.dispersed in porous and hy.rophilic interpenetrating poly.er networks(IPN),i.e.,Pd@IPN hy.rid gels,are employ.d for cataly.is of Suzuki and Heck coupling *** y.elds are obtained with high turnover frequencies when the reactions are run with very.low *** use of IPN gives better recy.lability.than that of crosslinked poly.iny. alcohol *** poly.er networks allow the reactants to have easy.access to the Pd *** cataly.ts combine high activity.with the reusability.offered by.the heterogeneous sy.tem,without the need for strong coordination or chelating ligands.

关键词： Nanoparticle Cataly.is Hy.rogels Palladium Water

PIV analy.is and high-speed photographic observation of cavitating flow field behind circular multi-orifice plates

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Water Science and Engineering 2020年第2期13卷 145-153页

作者： Zhi-ping Guo Xi-huan Sun Zhi-y.ng dong College of Hy.ro-Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Department of Transportation Engineering Shanxi Conservancy Technical InstituteYuncheng 044004China College of Civil Engineering and Architecture Zhejiang University of TechnologyHangzhou 310014China

Based on a self-developed hy.rody.amic cavitation device with different geometric parameters for circular multi-orifice plates,turbulence characteristics of cavitating flow behind multi-orifice plates,including the effects of orifice number and orifice lay.ut on longitudinal velocity.turbulence intensity.and Rey.olds stress,were measured with the particle image velocimetry.PIV)*** regimes of the cavitating flow were also observed with high-speed *** experimental results showed the following:(1)high-velocity.multiple cavitating jets occurred behind the multi-orifice plates,and the cavitating flow fields were characterized by.topological structures;(2)the longitudinal velocity.at each cross-section exhibited a sawtooth-like distribution close to the multi-orifice plate,and each sawtooth indicated one jet issuing from one orifice;(3)there were similar magnitudes and forms for the longitudinal and vertical turbulence intensities at the same cross-section;(4)the variation in amplitude of Rey.olds stress increased with an increase in orifice number;and(5)the cavitation clouds in the flow fields became denser with the increase in orifice number,and the clouds generated by.the staggered lay.ut of orifices were greater in number than those generated by.the checkerboard-ty.e one for the same orifice *** experimental results can be used to analy.e the mechanism of killing pathogenic microorganisms through hy.rody.amic cavitation.

关键词： Cavitating flow Circular multi-orifice plate PIV technique High-speed photography Turbulence characteristics

AocML： A Domain-Specific Language for Model-Driven Development of Activity.Oriented Context-Aware Applications

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Journal of Computer Science & Technology 2018年第5期33卷 900-917页

作者： Xuan-Song Li Xian-ping Tao Wei Song Kai dong School of Computer Science and Engineering Nanjing University of Science and Technology Nanfing 210093 China State Key.Laboratory.for Novel Software Technology Nanjing University Nanjing 210023 China School of Computer Science and Engineering Southeast University Nanjing 211189 China

Activity.oriented context-aware （AOCA） applications are representative in pervasive computing. These appli- cations recognize daily.life human activities, perceive the environment status related to the activities, and react to ensure the smooth performance of the activities. Existing research proposed a specific light-weight, incremental method to support the development of such applications; however it is not easy.to learn and use. This paper aims to facilitate the development of such applications and improve the productivity.of developers. We propose AocML, a textual domain-specific language which provides a high-level abstraction of AOCA applications. Specifically. we first show the software model of AOCA applications and the abstract sy.tax of AocML. Then, we introduce the concrete sy.tax of AocML. We also implement the tools for AocML, including the development environment as well as the generation of Java code and ontology.specification. Moreover, we use a case study.and evaluation to demonstrate the advantages of AocML.

关键词： pervasive computing context-awareness model-driven development domain-specific language

Effect of zirconium on inclusions and mechanical properties of China low activation martensitic steel

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Journal of Iron and Steel Research International 2021年第9期28卷 1168-1179页

作者： Guo-xing Qiu dong-ping Zhan Lei Cao Hui-shu Zhang School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Materials Engineering Department Hebei College of Industry and TechnologyShijiazhuang050091HebeiChina School of Metallurgy.Engineering Liaoning Institute of Science and TechnologyBenxi117004LiaoningChina

The effects of 0.01–0.11 wt.%Zr on the inclusions,microstructure,tensile properties,and impact toughness of the China low activation martensitic steel were *** showed that Zr exhibits good deoxidation and desulfurization *** scanning electron microscope was used to examine the inclusions in the *** main inclusions in the alloy. were Zr–Ta–O,Zr–O,and Zr–O–***,some blocky.Zr-rich inclusions appeared in Zr-2 and Zr-3 *** martensitic structures were observed in the alloy.,and average prior austenite grain sizes of 21.1,15.7,and 14.8µm were obtained for Zr-1,Zr-2,and Zr-3 steels,***,increasing Zr content of the steels deteriorated their mechanical property.owing to the blocky.*** alloy.with 0.01%Zr resulted in excellent mechanical properties due to the fine inclusions and the precipitation of Zr3V3C *** of 576 and 682 MPa were obtained for the y.eld strength and ultimate tensile strength of Zr-1 alloy.***,the ductile–brittle transition temperature of the alloy.decreased to−85℃.

关键词： China low activation martensitic steel Zr Inclusion Tensile strength Ductile-to-brittle transition temperature

Effect of electromagnetic stirrer centered outside the mold on steel flow field of bloom continuous casting

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China Foundry 2023年第5期20卷 461-468页

作者： Li-dong Xing y.n-ping Bao Min Wang y.-hong Li State Key.Laboratory.of Advanced Metallurgy University of Science and Technology Beijing(USTB)Beijing 100083China Technical Support Center for Prevention and Control of Disastrous Accidents in Metal Smelting University of Science and Technology Beijing(USTB)Beijing 100083China School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China

Mold electromagnetic stirring technology.for optimizing the flow of molten steel is now widely.used in the continuous casting production process of high-quality.***,studies on the case that the center of the electromagnetic stirrer is located outside the mold have not been ***,the effect of the electromagnetic stirrer centered outside the mold on the steel flow field was studied in detail by.means of numerical simulations.A Gauss meter was used to measure the magnetic induction intensity.at different positions,currents,and *** test results were compared with the simulation results of electromagnetic stirring to calibrate and verify.the accuracy.of the electromagnetic ***,electromagnetic force was introduced into the flow field model as a source term to study.its effect on the flow field under anomalous *** results show that when the center of the electromagnetic stirrer is located outside the mold,the magnetic field strength is about twice as strong as that located inside the *** also leads to an increase in the flow velocity.near the electromagnetic *** a result,the optimal electromagnetic stirring parameters(200 A,2.5 Hz)were specified when the center of the electromagnetic stirrer is located outside the mold.

关键词： numerical modeling electromagnetic stirring fluid flow outside the mold bloom