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Horticultural Plant Journal 2024年第2期10卷 355-366页

作者： Lili Dong chuxuan yang Jing Wang Jingjing Li Mei Zhao Dingli Li Zhiyun Qiu Chunhui Ma Zhenhua Cui College of Horticulture Qingdao Agricultural UniversityQingdaoShandong 266109China College of Landscape and Forestry Qingdao Agricultural UniversityQingdaoShandong 266109China

The lack of a suitable rootstock to control scion growth has limited the development of high-density plantations in pear production, which is partly attributed to poor understanding of the dwarfing mechanism. In the present study, the rootstock of the dwarf-type pear (Pyrus betulaefolia)PY-9’ was identified and used as the material for anatomical ***-9’ grew to half the tree height of the normal cultivar Zhengdu’, along with fewer internodes and shorter length. Significant differences in growth rate betweenPY-9’ andZhengdu’ were detected at approximately 30 days after full bloom, which corresponded with the time of the greatest difference in water potential between the dwarf and normal ***-9’ showed a higher photosynthetic rate thanZhengdu’. Anatomical analysis showed thatPY-9’ had higher area ratios of both phloem and xylem and more developed vascular tissues thanZhengdu’. The three-dimensional reconstructed skeleton of the xylem from X-ray computed tomography scanning revealed greater intervessel connectivity inZhengdu’ than inPY-9’, which could contribute to the more vigorous growth ofZhengdu’. This study thus provides the first comparison of the microstructural properties of xylem elements between a dwarfing-type and vigorous-type pear rootstock, providing new insights into the dwarfing mechanism in pear and facilitating breeding of dwarf pear rootstocks to increase crop productivity.

关键词： Pyrus betulaefolia Anatomical analysis Dwarfing mechanism Intervessel connectivity Rootstock

陕西米脂古城保护中社区居民参与的制度保障和实施措施探究

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遗产与保护研究 2019年第5期4卷 37-43页

作者：杨楚譞西北大学文化遗产学院

当今社会飞速发展,在新型城镇化建设的背景下,粗暴拆建时有发生,这使得古城保护遭遇到了新的危机和挑战。若要妥善保护古城原有风貌与文化内涵,仅靠政府的财政拨款是无法维持长久而又高效地保护工作运行。公众参与和居民参与既可以增加... 详细信息

当今社会飞速发展,在新型城镇化建设的背景下,粗暴拆建时有发生,这使得古城保护遭遇到了新的危机和挑战。若要妥善保护古城原有风貌与文化内涵,仅靠政府的财政拨款是无法维持长久而又高效地保护工作运行。公众参与和居民参与既可以增加大众的关注度,也可以减轻政府的压力,无疑为古城镇的保护提供了新的思路,但是这个过程却需要相关的制度保障以使工作正常运行。文章以米脂古城为例,通过对古城社区结构的材料分析及问卷的数据评估,探究古城镇保护中公众参与和居民参与的制度保障和实施措施。

关键词：古城镇米脂古城公众参与和居民参与制度保障

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秋月梨枝梢生长发育对花芽形成的影响

中国果树 2022年第3期 15-20页

作者：任李欣卢昱芹杨楚璇董莉莉崔振华马春晖青岛农业大学园艺学院山东266109

秋月梨为近年来引进的梨优良品种,对栽培技术要求较高。为探索秋月梨不同类型枝条生长发育对花芽形成的影响,对不同类型枝条的生长、组织结构、水分和养分运输、花芽重量等进行了调查。结果表明:不同结果枝类型影响花芽重量,其中徒长枝... 详细信息

秋月梨为近年来引进的梨优良品种,对栽培技术要求较高。为探索秋月梨不同类型枝条生长发育对花芽形成的影响,对不同类型枝条的生长、组织结构、水分和养分运输、花芽重量等进行了调查。结果表明:不同结果枝类型影响花芽重量,其中徒长枝水分通导率最大,导管直径最大,为44.8μm,花芽重量最小,为70.0 mg;中庸枝山梨醇含量最高,淀粉含量最高,为14.09%,花芽重量最大,为98.3mg;同时枝龄影响花芽重量,3年生枝条水分通导率最大,但花芽重量最小,为55.1mg。结果枝经济指标与花芽纵横径的相关性分析表明,枝条的淀粉含量、枝条粗度(<0.8cm)、花芽重量与花芽纵横径均呈显著或极显著正相关,枝条的花芽类型(长中短果枝花芽)与花芽纵横径呈显著或极显著负相关。综上,秋月梨枝梢生长发育与花芽重量关系密切,生产上控制好枝梢生长势和以短果枝花芽结果为主,有利于秋月梨的丰产稳产。

关键词：梨枝条花芽重量

Dynamic thermo-mechanical responses of road-soft ground system under vehicle load and daily temperature variation

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1722-1731页

作者： chuxuan Tang Jie Liu Zheng Lu yang Zhao Jing Zhang Yinuo Feng State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China Xinjiang Transportation Planning Survey and Design Institute Co. Ltd.Urumqi830006China Hubei Key Laboratory of Geo-Environmental Engineering Wuhan430071China

A complete road-soft ground model is established in this paper to study the dynamic responses caused by vehicle loads and/or daily temperature variation.A dynamic thermo-elastic model is applied to capturing the behavior of the rigid pavement,the base course,and the subgrade,while the soft ground is characterized using a dynamic thermo-poroelastic *** to the road-soft ground system are derived in the Laplace-Hankel transform *** time domain solutions are obtained using an integration *** temperature,thermal stress,pore water pressure,and displacement responses caused by the vehicle load and the daily temperature variation are *** show that obvious temperature change mainly exists within 0.3 m of the road when subjected to the daily temperature variation,whereas the stress responses can still be found in deeper places because of the thermal swelling/shrinkage deformation within the upper road ***,it is important to consider the coupling effects of the vehicle load and the daily temperature variation when calculating the dynamic responses inside the road-soft ground system.

关键词： Dynamic response Vehicle load Daily temperature variation Thermo-poroelastic medium Coupling effects

Effect of Incoming Vortex on Secondary Flows in Turbine Cascades with Planar and Non-Axisymmetric Endwall

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Journal of Thermal Science 2024年第1期33卷 138-157页

作者： CAO Zhiyuan WANG chuxuan SONG Zhigao GAO Xi ZHAO Wei LIU Bo School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China National Key Laboratory of Science and Technology on Aerodynamic Design and Research Northwestern Polytechnical UniversityXi'an 710072China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100080China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100080China

Non-Axisymmetric Endwall Profiling(NAEP) is commonly utilized in turbines to eliminate secondary ***,most of the NAEP methods consider a single-blade row environment without incorporating the effect of the stage *** paper aims to investigate the influence mechanism of the incoming vortex on the endwall secondary flow structures of NAEP in a highly loaded turbine *** model the incoming vortex in a stage environment,this study considers a half-delta wing as the vortex generator at the upstream of the turbine *** NAEP is then carried out for a highly loaded turbine cascade with an in-house numerical optimization design platform subject to no incoming *** simulation is also carried out under the influence of the incoming vortex for the turbine cascades with both planar and non-axisymmetric *** paper furthers investigated the pitchwise effect of the incoming vortex on the near endwall secondary *** results indicate that the NAEP effectively improves the endwall secondary flow of the turbine cascade,where the total pressure loss coefficient and the secondary kinetic energy(SKE) are reduced by 7.3%,and 45.7%,*** is further seen that with the incoming vortex,the NAEP achieves a considerable control effect on the endwall secondary flow of the turbine *** incoming vortex,the NAEP can still achieve considerable control effect on the endwall secondary flow of the turbine cascade;the averaged reductions of loss coefficient and SKE are 7.8% and 14.2%,*** some pitchwise locations,incoming vortex can suppress the convection of cross-passage flow toward the suction corner greatly and reduce the loss coefficient of the baseline *** incoming vortex at 4/7 pitch impinged right at the blade leading edge,leading to the generation of low-momentum fluid,which increased the size and the strength of the horseshoe *** all the pitchwise locations,NAEP can suppress the seco

关键词： non-axisymmetric endwall secondary flow incoming vortex passage vortex stage environment

A practical method for identifying key factors in the distribution and formation of heavy metal pollution at a smelting site

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Journal of Environmental Sciences 2023年第5期127卷 552-563页

作者： Jiaqing Zeng Wenshun Ke Min Deng Jingqiang Tan chuxuan Li Yizhi Cheng Shengguo Xue School of Metallurgy and Environment Central South UniversityChangsha 410083China School of Geosciences and Info-physics Central South UniversityChangsha 410083China New World Environment Protection Group of Hunan Changsha 410083China

Smelting activities are the main pathway for the anthropogenic release of heavy metals(HMs)into the soil-groundwater *** is vital to identify the factors affecting HMs pollution to better prevent and manage soil *** present study conducted a comprehensive investigation of HMs in soil from a large abandoned Zn smelting *** integrated approach was proposed to classify and quantify the factors affecting HMs pollution in the ***,the quantitative relationship between hydrogeological characteristics,pollution transmission pathways,smelting activities and HMs pollutionwas *** showed that the soils were highly contaminated by HMs with a pollution index trend of As>Zn>Cd>Pb>*** identifying the pollution hotspots,we conclude that the pollution hotspots of Pb,As,Cd,and Hg present a concentrated distribution ***-detector method results showed that the dominant driving factors for HMs distribution and accumulation were the potential pollution source and soil ***,the main drivers are variable for different HMs,and the interaction among factors also enhanced soil HMs *** analysis illustrates how the confounding influences from complex environmental factors can be distilled to identify key factors in pollution formation to guide future remediation strategies.

关键词： Zinc smelting site Heavy metal pollution Spatial distribution Hotspot identification Geographical detector

Alkalinity neutralization and structure upgrade of bauxite residue waste via synergistic pyrolysis with biomass

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Journal of Environmental Sciences 2020年第7期32卷 41-47页

作者： chuxuan Li Lu Tang Jun Jiang Feng Zhu Jingju Zhou Shengguo Xue School of Metallurgy and Environment Central South UniversityChangsha 410083China

Bauxite residues,a large volume solid waste,are in urgent need of effective disposal and ***,strategies to alleviate the high alkalinity of bauxite residue remain a big ***,we developed a synergistic pyrolysis to neutralize the alkalinity of bauxite residue and upgrade the structure of biomass *** cooperating the catalytic feature from bauxite residue,rice straw,a cellulose-enriched biomass,could prefer to produce acidic components under a hypothermal pyrolysis temperature(below 250℃)and partial oxygen-contained atmosphere as evidenced by the synchronous TGA-FTIR *** return,these in-situ produced acidic components neutralized the bauxite residue profoundly(pH decreased from 11.5 to 7.2)to obtain a neutral product with long-term water leaching ***,a higher pyrolysis temperature led to neutral biochar-based products with well-defined carbonization ***,the biomass-driven pyrolysis strategy provides a potential to dispose the alkalinity issue of bauxite residue and further opportunities for the sustainable reuse and continuing management of bauxite residue.

关键词： Bauxite residue Rice straw Alkali neutralization Pyrolysis Biochar

Phosphogypsum stabilization of bauxite residue:Conversion of its alkaline characteristics

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Journal of Environmental Sciences 2019年第3期31卷 1-10页

作者： Shengguo Xue Meng Li Jun Jiang Graeme J.Millar chuxuan Li Xiangfeng Kong School of Metallurgy and Environment Central South University Institute for Future Environments Science and Engineering Faculty Queensland University of Technology

Reduction of the high alkalinity of bauxite residue is a key problem to solve to make it suitable for plant growth and comprehensive utilization. In this study, phosphogypsum, a waste product from the phosphate fertilizer industry, was used to drive the alkaline transformation of the bauxite residue. Under optimal water washing conditions(liquid/solid ratio of 2 mL/g, 30°C, 24 hr), the impact of quantity added, reaction time and reaction mechanism during phosphogypsum application were investigated. Phosphogypsum addition effectively lowered p H levels and reduced the soluble alkalinity by 92.2%. It was found that the concentration of soluble Na and Ca ions in the supernatant increased gradually, whilst the exchangeable Na+and Ca^(2+)in solid phase changed 112 mg/kg and 259 mg/kg, respectively. Ca^(2+)became the dominant element in the solid phase(phosphogypsum addition of 2%, liquid/solid ratio of 2 mL/g, 30°C, 12 hr). X-ray diffraction data indicated that cancrinite and hydrogarnet were the primary alkaline minerals. SEM images suggested that phosphogypsum could promote the formation of stable macroaggregates, whilst the content of Ca^(2+)increased from 5.6% to 18.2% and Na reduced from 6.8% to 2.4%. Treatment with phosphogypsum could significantly promote the transformation of alkalinity cations by neutralization, precipitation and replacement *** research provided a feasible method to promote soil formation of bauxite residue by phosphogypsum amendment.

关键词： Bauxite residue Phosphogypsum Alkaline ions Alkaline transformation Soil formation

Elastic-viscoplastic behaviors of polymer-blend geocell sheets:Numerical and experimental investigations

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第10期16卷 4261-4271页

作者： yang Zhao Jianbin Chen Zheng Lu Jie Liu Abdollah Tabaroei chuxuan Tang Yong Wang Lipeng Wu Bo Wang Hailin Yao State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China Wuhan Municipal Engineering Design&Research Institute Co. Ltd.Wuhan430023China Hubei Key Laboratory of Geo-Environmental Engineering Wuhan430071China Xinjiang Transportation Planning Survey and Design Institute Co. Ltd.Urumqi830006China Department of Civil Engineering Eshragh Institute of Higher EducationBojnourd***Iran University of Chinese Academy of Sciences Beijing100049China China Energy Engineering Gezhouba Rail Transit Construction Co. Ltd.Shenzhen518116China

Polymer-blend geocell sheets(PBGS)have been developed as substitute materials for manufacturing *** attempts have been made to test and predict the behaviors of commonly used geogrids,geotextiles,geomembranes,and ***,the elastic-viscoplastic behaviors of novel-developed geocell sheets are still poorly ***,this paper investigates the elastic-viscoplastic behaviors of PBGS to gain a comprehensive understanding of their mechanical ***,the tensile load-strain history under various loading conditions is simulated by numerical calculation for widespread *** achieve this goal,monotonic loading tests,short-term creep and stress relaxation tests,and multi-load-path tests(also known as arbitrary loading history tests)are performed using a universal testing *** results are simulated using the nonlinear three-component(NLTC)model,which consists of three nonlinear components,i.e.a hypo-elastic component,a nonlinear inviscid component,and a nonlinear viscid *** experimental and numerical results demonstrate that PBGS exhibit significant elastic-viscoplastic behavior that can be accurately predicted by the NLTC ***,the tensile strain rates significantly influence the tensile load,with higher strain rates resulting in increased tensile loads and more linear load-strain ***,parametric analysis of the rheological characteristics reveals that the initial tensile strain rates have negligible impact on the *** rate-sensitivity coefficient of PBGS is approximately 0.163,which falls within the typical range observed in most geosynthetics.

关键词： Polymer-blend geocell sheets Geosynthetics Elastic-viscoplastic behavior Numerical simulations Tensile load-strain response

Migration and distribution characteristics of soil heavy metal(loid)s at a lead smelting site

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Journal of Environmental Sciences 2024年第1期135卷 600-609页

作者： chuxuan Li Mu Li Jiaqing Zeng Shanxin Yuan Xinghua Luo Chuan Wu Shengguo Xue School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution Central South UniversityChangsha 410083China

Heavy metal(loid)s contamination is a constant issue at smelting *** is essential to investigate the spatial distribution and migration characteristics of heavy metal(loid)s in the soil for environmental management and remediation strategies of non-ferrous smelting *** this study,203 soil samples from 57 sites were collected in a typical lead smelting *** findings demonstrated that there were significant Pb,Zn,Cd,and As contamination in soil *** spatial distribution of heavy metal(loid)s showed strong spatial heterogeneity,the contaminated soil areas of Pb,As,Cd,and Zn were 99.5%,98.9%,85.3%,and 72.4%,***,Cd,and As contamination of the soil reached a depth of 5 m,which migrated from the surface to deep soil *** leaching contents of Zn,Pb,and As decreased obviously in 3-4 m soil layer,but the leaching content of Cd was still high,which indicated the high migration of *** the increase of depth,the proportion of acid soluble fraction of heavy metal(loid)s decreased,and the residual fraction *** acid soluble fraction of Cd accounted for a higher proportion,and As mainly existed in reducible and residual fractions in *** to the calculation of the migration factor,the migration of heavy metal(loid)s in soils were ordered as Cd>Zn>Pb>*** outcomes are advantageous for risk reduction and site remediation for non-ferrous metal smelting sites.

关键词： Smelting sites Heavy metal(loid)s Spatial distribution Chemical speciation Migration characteristics