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Wind-sand flow simulation and radius optimization of highway embankment under different vertical curve radius

Journal of Mountain Science 2024年第8期21卷 2533-2546页

作者： LI Liangying LI Qi WANG Xu XIN Guowei WANG zhenqiang School of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

It is of great practical value to explore the correlation between the vertical curve radius of desert highway and the increase of sand accumulation in local lines,and to select the appropriate vertical curve radius for reducing the risk of sand *** this study,three-dimensional models of desert highway embankments with different vertical curve radii were constructed,and Fluent software was used to simulate the wind-sand flow field and sand accumulation distribution of vertical curve *** results show that:(1)Along the direction of the road,the concave and the convex vertical curve embankments have the effect of collecting and diverging the wind-sand flow,*** the radius of the concave vertical curve is 3000 m,5000 m,8000 m,10000 m and 20000 m,the wind velocity in the middle of the vertical curve is 31.76%,22.58%,10.78%,10.53%and 10.44%,higher than that at both *** the radius of the convex vertical curve is 6500 m,8000 m,10000 m,20000 m and 30000 m,the wind velocity at both ends of the vertical curve is 14.06%,9.99%,6.14%,3.22%and 2.41%,higher than that in the *** diversion effect also decreases with the increase of the radius.(2)The conductivity of the concave and convex vertical curve embankments with different radii is greater than 1,which is the sediment transport *** conductivity increases with the increase of radius and gradually tends to be *** the radius of the concave and convex vertical curves reaches 8000 m and 20000 m respectively,the phenomenon of sand accumulation is no longer *** the same radius condition,the concave vertical curve embankment is more prone to sand accumulation than the convex one.(3)Considering the strength of the collection and diversion of the vertical curve embankment with different radii,and the sand accumulation of the vertical curve embankment in the desert section of Wuma Expressway,the radius of the concave vertical curve is not less than 8000 m,and the r

关键词： Highway engineering Vertical curve Numerical simulation Embankment wind-sand flow Radius optimization

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Surface warming patterns dominate the uncertainty in global water vapor plus lapse rate feedback

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Acta Oceanologica Sinica 2020年第3期39卷 81-89页

作者： Jingchun Zhang Jian Ma Jing Che zhenqiang Zhou Guoping Gao College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China College of Marine Science and Engineering Shanghai Maritime UniversityShanghai 201306China

Climate feedbacks have been usually estimated using changes in radiative effects associated with increased global-mean surface temperature. Feedback uncertainties, however, are not only functions of global-mean surface temperature increase. In projections by global climate models, it has been demonstrated that the geographical variation of sea surface temperature change brings significant uncertainties into atmospheric circulation and precipitation responses at regional scales. Here we show that the spatial pattern of surface warming is a major contributor to uncertainty in the combined water vapour-lapse rate feedback. This is demonstrated by computing the global-mean radiative effects of changes in air temperature and relative humidity simulated by 31 climate models using a methodology based on radiative kernels. Our results highlight the important contribution of regional climate change to the uncertainty in climate feedbacks, and identify the regions of the world where constraining surface warming patterns would be most effective for higher skill of climate projections.

关键词： surface warming patterns uncertainty water vapor feedback lapse rate feedback relative humidity air temperature radiative kernels

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Exo/endogenous factors co-activatable nanodevice for spatiotem-porally controlled miRNA imaging and guided tumor ablation

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Nano Research 2022年第2期15卷 845-857页

作者： zhenqiang Wang Tao Ding Liucan Wang Shuai Wang Meizhen Zhou Jixi Zhang Kaiyong Cai Key Laboratory of Biorheological Science and Technology Ministry of EducationCollege of BioengineeringChongqing UniversityChongqing 400044China

Remote activation of biomarker sensing holds a great promise of shifting the success of in vitro diagnostics to spatiotemporally controlled in vivo visualization of tumor,and in turn,imaging guided ***,a"dual-key-one-lock"nanodevice was designed and built by assembling thermo-activatable probe of trimeric DNA hybrids into a mesoporous polydopamine nanoparticle-based multifunctional nanotransducer(probe host,fluorescence quencher,and photothermal conversion agent),enabling precisely switchable theranostic operations under the co-activation of exo/endogenous stimulations(near-infrared(NIR)light and microRNA(miRNA)).By this design,the NIR irradiation-induced local heat through the porous nanotransducer can be transferred to the DNA nanothermometer for triggering the exposure of the miRNA recognition segment,as well as the subsequent fluorescence activation by strand displacement reactions(SDR).A programmable application of short-(3 min)and long-duration(10 min)NIR irradiation was administered sequentially to induce a milder and a stronger hyperthermia,respectively,to activate the localized miRNA imaging,and in turn,tumor thermoablation under the fluorescence guidance in *** reducing nonspecific activation,dual factor co-activatable nanodevices exhibited a high tumor-to-background ratio(TBR)value of 8.9,as well as a significantly lower(6-9-fold)normal tissue fluorescence as compared with those sensing miRNA *** in vivo results show that the tumors were significantly suppressed after the photothermal therapy with the assistance of the accurate miRNA *** rationally integrated nanoplatform may pave a new avenue for advanced theranostic systems with high spatiotemporal precision by activatable designs.

关键词： thermo-activatable probe porous nanotransducer photothermal activation spatiotemporal miRNA imaging imaging-guided therapy

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Surface deformation under overlapping impacts of solid particles

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Friction 2023年第2期11卷 280-301页

作者： Xuerui ZANG Xuewen CAO zhenqiang XIE Jun ZHANG Farzin DARIHAKI Yang LIU College of Pipeline and Civil Engineering China University of Petroleum(East China)Qingdao 266580China Erosion/Corrosion Research Center The University of TulsaTulsa 74104USA

To improve the accuracy of erosion prediction,the effect of subsequent particles impacting the same area while the first single particle rebounds from the substrate must be *** issue has rarely been considered in studies pertaining to erosion *** the present study,the ABAQUS software is used to investigate the erosion crater morphology and stress distribution on a target material subjected to overlapping impacts of spherical ***,the validated model is applied to investigate the effect of the overlapping impacts of particles on the ***,the correlation between erosion severity and the impact locations of the two incident particles is *** results show that the horizontal distance between two solid particle impact locations can significantly affect the erosion magnitude and *** interactions of the resulting craters diminish when the horizontal distance exceeds 0.6 times the particle *** the horizontal distance is approximately 0.06 times the particle diameter,the energy loss originating from collisions reaches the maximum,which modifies the crater *** present study is expected to provide in-depth insights into erosion mechanisms and erosion modeling.

关键词： overlapping impact spherical particle surface morphology energy dissipation ABAQUS simulation

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Effect of filter-feeding fish silver carp on phytoplankton species and size distribution in surface water:A field study in water works

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Journal of Environmental Sciences 2010年第2期22卷 161-167页

作者： Hua Ma Fuyi Cui Zhiquan Liu zhenqiang Fan Wenjie He Peijun Yin State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology Harbin 150090 China Tianjin Waterworks Group Co. Ltd. Tianjin 300040 China

Silver carp were introduced into the pre-sedimentation pond to control excessive phytoplankton in raw water. The effectiveness of the filter-feeding silver carp on phytoplankton control and the effect of silver carp on phytoplankton community were investigated. The results showed that Microcystis could be effectively removed by silver carp stocked in the pre-sedimentation pond, and simultaneously, the concentration of single-cell phytoplankton increased obviously. The difference in phytoplankton species and single- cell phytoplankton size between in the water and in the gut of silver carp indicated that phytoplankton smaller than 5 μm, such as Chamydomonas and Platymonas, were almost not be filtered by silver carp, phytoplankton with the size between 5 and 20μm could be partly filtered, and large size phytoplankton, mainly colony-forming Microcystis could be filtered almost completely. These filter- feeding characteristics directly caused the phytoplankton size distribution biased toward miniaturization. Therefore, this biological treatment using silver carp could be applied only to deal with groups of Microcystis-dominated eutrophic water, and was not appropriate in water bodies where single-cell micro phytoplankton were dominant. Especially when silver carp are used in water treatment, a cautious attitude should be taken based on the evaluation of phytoplankton biomass and species structure features in raw water.

关键词： phytoplankton control silver carp Microcystis single-cell micro phytoplankton

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Challenges and Perspectives of Information and Control Technology for Cislunar Space Exploration and Development

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Guidance, Navigation and Control 2023年第2期3卷 1-19页

作者： Weimin Bao zhenqiang Qi Science and Technology Commission of China Aerospace Science and Technology Corporation Fucheng Road 16 Beijing 100048P.R.China China Academy of Launch Technology Nandahongmen Road 1 Beijing 100854P.R.China

Cislunar space,asthe first station for mankind to go into space,will be the main destination and outpost of space missions for a long period oftime in the *** the course of the cislunar space exploration and development,information and control technology will play an important *** view of the object scope and mission background of cislunar space exploration and development,this paper firstly summarizes the mission characteristics,***,longer,more and complex,and then analyzes the requirements and challenges for information and control *** that,the strategy including intelligent algorithm,open architecture,cloud-enabled information and reliable flight is ***,several prospectives are given to deal with some issues in future large-scale cislunar space exploration and development.

关键词： Cislunar space information and control challenges and perspectives

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Study on Heating Uniformity of Pt-Rh Alloy Bushing for Producing Flexible Glass

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Journal of Wuhan University of Technology(Materials Science) 2022年第2期37卷 256-260页

作者： GUO zhenqiang YUAN Jian TIAN Peijing Shahe Research Institute of Glass Technology Wuhan 430070China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyShahe 054100China

The numerical simulation for temperature distribution of Pt-Rh alloy bushing was carried out using a thermal-electric module in ANSYS Workbench finite element analysis *** effects of side wall thickness,plug thickness,the angle of two side walls and electrode structure on the uniformity of temperature distribution were ***,the contrastive analysis results of bushing with and without glass melt were *** simulation results show that,when the homogeneous glass melt flows through bushing,the temperature difference between the center and both ends of bushing is decreased significantly,but the temperature distribution at both ends of bushing is still affected by heating non-uniformity of *** with side wall thickness,plug thickness and the angle of two side walls,electrode structure plays a greater role in adjusting heating uniformity of bushing.

关键词： flexible glass Pt-Rh alloy bushing heating uniformity

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Study of the best decocting time of sun dried ginseng by using the hyperspectral imaging technology

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Journal of Innovative Optical Health Sciences 2016年第6期9卷 21-25页

作者： Qing He Lan Liang zhenqiang Chen Qichang Pang Jing Zhao Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Educational Institutes Jinan University Guangzhou 510630P.R.China Department of Biomedical Engineering Guangdong Medical College Dongguan 523808 P.R.China College of Science South China Agricultural University Guangzhou 510640P.R.China

In this research,a new method based on the hyperspectral imaging for searching the best decocting time of sun dried ginseng is *** spectral images at diferent decocting time of test sample have been taken by the st aring hyperspectral fAuorescence imaging systen and the solubility of active ingredients have been discussed by analyzing the changes on the *** spectr al range of the system is 400-720nm and the spectral resolution is *** the decocting process,the active ingredients of nonsoaked ginseng was dissolved in the tissue fluid at first,and reached equilibrium condition at last after the precipitation-dissolution reciprocating process of *** last,the experiment al results show that the best decoction time of sun dried ginseng is about 60 min after boiling.

关键词： Sun dried ginseng active ingredients decocting time hyperspectral imaging characteristic spectrum characteristic peaks

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Theoretical prediction for effective properties and progressive failure of textile composites:a generalized multi-scale approach

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Acta Mechanica Sinica 2021年第8期37卷 1222-1244,I0001页

作者： Haoyuan Dang Peng Liu Yinxiao Zhang zhenqiang Zhao Liyong Tong Chao Zhang Yulong Li Department of Aeronautical Structure Engineering Northwestern Polytechnical UniversityXi’an 710072 China 2 Shaanxi Key Laboratory of Impact Dynamics and Its Engineering Applications Xi’an 710072 China 3 Joint International Research Laboratory of Impact Dynamics and Its Engineering Applications Xi’an 710072 China 4 School of Science Harbin Institute of TechnologyShenzhen 518055 China 5 School of Aerospace Mechanical and Mechatronic EngineeringThe University of SydneySydneyNSW 2006Australia

A generalized analytical model is developed to predict progressive failure behavior of several types of textile composites,including plain weave composites,twill weave composites,two-dimensional tri-axially braided composites and warpreinforced 2.5-dimensional braided *** this model,the unit cell(UC)of composite is firstly identified and reconstructed into a refined lamina structure with multiple equivalent lamina elements(ELEs)based on apt geometrical approximation and ***,two-way coupled stress-strain responses within the UC(macro-scale)and ELE(meso-scale)are established through a universal series-parallel model(SPM).Finally,a progressive damage model,which consists of damage initiation criteria and a stiffness evolution strategy,is employed to predict damage behavior of the *** analytical results including mechanical properties and progressive failure process are validated against the existing numerical and experimental ones in *** validated analytical model is then used to study the effects of global fiber volume fraction,braided angle,shear failure coefficient and selected failure criteria on stiffness,strength and failure *** present results demonstrate the efficiency and generic capability of the present analytical model for predicting the mechanical responses of a range of textile composites.

关键词： Textile composites Analytical model Series-parallel model Damage mechanics Strength

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Super-High Initial Velocity Mechanism of Bullet Propulsion with Adaptive Pressure-Maintaining Chamber

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Journal of Beijing Institute of Technology 2020年第1期29卷 23-28页

作者： Junbo Xiao Hongqiang Li zhenqiang Liao Ming Qiu Jie Song School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

To deal with the problem that the initial velocity of the bullet is difficult to increase,the research on the super-high initial velocity propulsion in the barrel weapon with an adaptive pressure-maintaining chamber are *** the law of gun-powder burning and the flow characteristics of gun-powder gas in multi-chamber,the scheme of super-high initial velocity propulsion with an adaptive pressure-maintaining chamber is designed,the ballistic model of the barrel weapon with super-high velocity bullet propulsion is *** research results show that the technical scheme can greatly increase the initial velocity of the bullet with the peak pressure keeping nearly the same as the tradition barrel *** research results can provide a theoretical foundation to significantly increase the initial velocity in barrel weapons using solid propellants,and have an important reference value to comprehensively increase the power of the barrel weapons.

关键词： inner trajectory adaptive pressure-maintaining chamber super-high initial velocity propulsion barrel weapon

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