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Science China(Technological Sciences) 2020年第2期63卷 341-356页

作者： XIONG GuoJun CHEN JinJian li mingguang li Yaoliang State Key Laboratory of Ocean Engineering Department of Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Foundation Engineering Group Co. LtdShanghai 200433China

Existing solutions for axisymmetric active earth pressure are based on certain hypotheses of the circumferential stress, lacking of strict basis. This article presents a technique for deriving the actual circumferential stress according to the circumferential geometric condition, the Drucker-Prager criterion and incremental theory. Based on the actual circumferential stress, a new characteristics method for determining the axisymmetric active earth pressure in plastic flow is developed in this article. In this new method, the inclined angle of boundaries, interface friction of contact interface, dilatation effect and flow velocity of soil are considered at the same time. The validity of the new method is confirmed using several sets of experimental data from the literature. The pressure coefficients are investigated individually in detail, and some different conclusions are found. Finally, a practical formula for calculating axisymmetric active earth pressure is presented based on the linear superposition principle, and related tables of coefficients are also provided for engineering application.

关键词： axisymmetric active earth pressure characteristics method practical calculation formula earth pressure coefficients dilatation effect the Drucker-Prager yield criterion

Strength and dilatancy behaviors of deep sands in Shanghai with a focus on grain size and shape effect

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第6期12卷 1214-1225页

作者： Bandana Tiwaria Guanlin Ye mingguang li Usama Khalid Santosh Kumar Yadav Department of Civil Engineering and State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai200240China Department of Civil Engineering IOEPulchowk CampusTribhuvan UniversityLalitpur44700Nepal

With rapid development of infrastructures like tunnels and open excavations in Shanghai,investigations on deeper soils have become critically *** of the existing laboratory works were focused on the clayey strata up to Layer 6 in Shanghai,*** depth of up to 40 *** this paper,Layers 7,9,and 11,which were mostly formed of sandy soils at depth of up to 150 m,were experimentally investigated with respect to physico-mechanical *** stressestrain behaviors were analyzed by the consolidated drained/undrained(CD/CU)triaxial tests under monotonic ***-dimensional(1D)oedometer tests were performed to investigate the consolidation properties of the sandy *** were prepared at three different relative densities for each ***,the micro-images and particle size analyzers were used to analyze the shape and size of the sand *** influences of grain size,density,and angularity on the stressestrain behaviors and compressibility were also *** to the other layers,Layer 11 had the smallest mean grain size(D50),highest compressibility,and lowest shear *** contrast,Layer 9 had the largest mean grain size,lowest compressibility,and highest shear *** 7 was of intermediate mean grain size,exhibiting more compressibility and less shear strength than that of Layer ***,the critical state parameters and maximum dilatancy rate of different layers were discussed.

关键词： Deep sands in Shanghai Laboratory tests Shear strength Dilatancy Relative density

Effect of Wall Deformation on Dewatering-Induced Ground Surface Settlement

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Journal of Shanghai Jiaotong university(Science) 2020年第4期25卷 417-425页

作者： NAI Kimsrorng li mingguang CHEN Jinjian State Key Laboratory of Ocean Engineering/Department of Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In practice,dewatering for pressure relief is commonly undertaken during ongoing excavation to secure bottom stability against basal ***,through unloading,wall deflection is obviously *** that both cause soil deformations,this research is to study the effect of wall deformation on dewateringinduced settlement.A coupled numerical analysis of finite-difference software is employed to model Shanghai soft soils under multi-aquifer-aquitard systems(MAASs)by analyzing the results in association with an empirical ***,through gradual force reduction,shear strength at soil-wall interface is significantly *** wall deformation increases instantaneously upon lower loading,wall surface becomes deformedly bending;this condition causes the challenge to workability of shear ***,wall deformation caused by unloading affects dewatering-induced settlement *** smaller loading,large wall deflection is observed;soil plane of failure caused by both sliding and compression occurs along slip curve,with weaker shear-strength soils at rD=0.4 and stronger shear-strength soils between rD=0.4 and rD=0.65,where rD is the distance from the wall that is normalized by the depth measured from ground *** dewatering,stronger soils tend to drag weaker soils upward to reduce large differential settlements caused by additional ***,settlement becomes larger at rD=0.4 and smaller at rD=***,at rD>2.3,both settlement curves that result from numerical analysis and empirical method show overlapping;this indicates that the unloading effect on dewatering-induced settlement at rD>2.3 is ***,as wall reaches maximum allowable wall deflection by 67%applied force,additional compression caused by dewatering after loading remains smaller than that under 70%applied force,contributing to smaller dewatering-induced settlement.

关键词： dewatering wall deformation confined aquifer groundwater ground surface settlement

Resonance hosts for high efficiency solution-processed blue and white electrophosphorescent devices

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Science China Chemistry 2020年第11期63卷 1645-1651页

作者： Huanhuan li Jibiao Jin Yuan Xiang Ying Zhang Ye Tao mingguang li Qin Xue Guohua Xie Wei Huang Runfeng Chen Key Laboratory for Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Nanjing University of Posts&TelecommunicationsNanjing 210023China Sauvage Center for Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic MaterialsDepartment of ChemistryWuhan UniversityWuhan 430072China Frontiers Science Center for Flexible Electronics(FSCFE) Shaanxi Institute of Flexible Electronics(SIFE)&Shaanxi Institute of Biomedical Materials and Engineering(SIBME)Northwestern Polytechnical University(NPU)Xi’an 710072China

The exploration of high-performance solution-processible host materials for blue and white electrophosphorescent devices is a key and fundamental challenge in the ongoing development of organic ***,two solution-processible resonance host materials with self-adaptive characteristics are delicately designed and *** of the dynamic tautomerization upon resonance variation,these smart hosts show self-adaptive and selectively enhanced charge carrier flux at high triplet energy *** by the resonance molecules,solution-processed blue and white devices exhibit excellent maximum current efficiencies(CEs)of 29.8 and 57.3 cd A−1,and external quantum efficiencies(EQEs)up to 14.5%and 23.5%,*** works highlight the significant progress of the solution-processed phosphorescent organic light-emitting diodes(PhOLEDs)using resonance host molecules,potentially furnishing a leap forward in constructing advanced organic semiconductors for next-generation optoelectronic devices.

关键词： solution-processed resonance hosts dynamic self-adaptation high-efficiency electrophosphorescence

Seed,cutting and air-layering reproductive inefficiency of noxious woody vine Merremia biosiana and its implications for management strategy

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Frontiers in Biology 2009年第3期4卷 342-349页

作者： mingguang li Haiyang liU Fenglan li Xiuyuan CHENG Bin GUO Zhiwei FAN State Key Laboratory of Biocontrol Sun Yat-sen UniversityGuangzhou 510275China Environment and Plant Protection Institute Chinese Academy of Tropical Agricultural SciencesDanzhou 571737China

Merremia boisiana(Gagnep)van *** a noxious fast growing woody vine and is able to grow overtop other plants,causing the death of plants underneath and forming monospecies *** formulate management responses,we assessed its seed and vegetative reproduction efficacy through indoor and field *** number of flowers counted from bagged infructescences in Guangzhou ranged from 25 to 172,with an average of *** the seeds of bagged infructescences had shown that there were only 1.58 hard testa seeds in each *** vitality tests using red ink indicated that only 68.6%of hard testa and filled seeds were *** emergence rate of scarified hard testa seeds in the sand bed was 31.96%.Under imitated natural conditions,8%of hard testa seeds could germinate,and 9%still retained their germination potential in one ***,seedlings should be monitored and removed in a timely fashion after any attempt of *** soil or transplanting plant from infested patches should be strictly prohibited at least for several *** considered,an infructescence contributed 0.3 *** investigation in the field found no seedlings either inside or at the perimeter of the patch,suggesting scant expansion by means of seed ***,the elimination effort could be focused on a relatively restricted scale of *** 630 cuttings of young shoots,old shoots and old lying shoots with or without growth regulators,there were only four(or 0.63%)established ***-layering shoots all died in two *** cuttings and airlayering reproduction indicated that regeneration from fragments of removed stems or accidentally dropped ones was quite unlikely,and thus mechanical removal was safe.

关键词： Merremia boisiana seed vitality germination rate vegetative reproduction management

Enhancing lead-free photovoltaic performance:Minimizing buried surface voids in tin perovskite films through weakly polar solvent pre-treatment strategy

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Journal of Energy Chemistry 2024年第11期98卷 556-561页

作者： Dongdong Yan Han Zhang Chensi Gong Hailong Wang Qing Lu Jun liu Wenzhen Lv mingguang li Runfeng Chen ligang Xu Key Laboratory for Organic Electronics and Information Displays(KLOEID)&Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing University of Posts&TelecommunicationsNanjing 210023JiangsuChina National Institute of Metrology Beijing 100029China School of Pharmacy North Sichuan Medical CollegeNanchong 637100SichuanChina School of Optoelectronic Science and Engineering&Collaborative Innovation Center of Suzhou Nano Science and Technology Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province&Key Lab of Modern Optical Technologies of Education Ministry of ChinaSoochow UniversitySuzhou 215031JiangsuChina

Buried interfacial voids have always been a notorious phenomenon observed in the fabrication of lead perovskite films. The existence of interfacial voids at the buried interface will capture the carrier, suppress carrier transport efficiencies, and affect the stability of photovoltaic devices. However, the impact of these buried interfacial voids on tin perovskites, a promising avenue for advancing lead-free photovoltaics, has been largely overlooked. Here, we utilize an innovative weakly polar solvent pretreatment strategy(WPSPS) to mitigate buried interfacial voids of tin perovskites. Our investigation reveals the presence of numerous voids in tin perovskites during annealing, attributed to trapped dimethyl sulfoxide(DMSO) used in film formation. The WPSPS method facilitates accelerated DMSO evaporation, effectively reducing residual DMSO. Interestingly, the WPSPS shifts the energy level of PEDOT:PSS downward, making it more aligned with the perovskite. This alignment enhances the efficiency of charge carrier transport. As the result, tin perovskite film quality is significantly improved,achieving a maximum power conversion efficiency approaching 12% with only an 8.3% efficiency loss after 1700 h of stability tests, which compares well with the state-of-the-art stability of tin-based perovskite solar cells.

关键词： Tin perovskite Buried interfacial Weakly polar solvent pre-treatment strategy

Safety Evaluation Method for Long-Term Operation of Metro Based on Combination Weighting Method

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Journal of Shanghai Jiaotong university(Science) 2020年第6期25卷 700-705页

作者： CAO Weiwei li mingguang WU Wei XIA Xiaohe SHI Yujin State Key Laboratory of Ocean Engineering Department of Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Geological Survey Shanghai 200072China

Metros are critical infrastructure in big cities and evaluation of their safe operation is of increasing *** make a reasonable safety evaluation for the metro during operation,this paper establishes a rational safety evaluation model based on long-term monitoring data of Shanghai Metro line *** evaluation indicators,ie.,absolute settlement,relative curvature,deformation rate and curvature radius,are *** hierar-chy process(AHP)and entropy method are combined to determine the weights of the *** risk level values at different mileage are calculated and five danger levels are defined accordingly to determine the safety state of Shanghai Metro line 2,ie.,safe,relatively safe,critical,relatively dangerous,and *** evaluation of Shanghai Metro line 2 shows that:83.81%areas of Shanghai Metro line 2 are in safe,relatively safe and critical states,while 15.63%and 0.57%areas are in relatively dangerous and dangerous states,respectively;the parts of Shanghai Metro line 2 where the risk level values exceed the critical value are mainly distributed around the mileage at 6.0-7.5km and 8.5-11.0 km,and the risk level value peaks around the mileage at 7.3km,to which much attention should be attached and relevant protective measures be taken;the sections with the high risk level values coincide with the distinctly deforming arcas of the metro,indicating that this evaluation method is valid.

关键词： long-term deformation safety evaluation combination weighting method Shanghai Metro

Numerical Study on Groundwater Drawdown and Deformation Responses of Multi-Layer Strata to Pumping in a Confined Aquifer

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Journal of Shanghai Jiaotong university(Science) 2019年第3期24卷 287-293页

作者： WANG Dafa li mingguang CHEN Jinjian XIA Xiaohe ZHANG Yangqing School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University

Pumping artesian water from porous media inevitably reduces the groundwater head and promotes soil consolidation,which may result in regional land *** this study,a fluid-mechanical coupled numerical model is developed to investigate the dewatering-induced groundwater drawdown and deformation responses for multi-layer *** relation bet ween the stra tum deformation and groundwater drawdown is *** results show that the pumping process can be divided into four st *** development of vertical deformation is inconsistent with the change of the pore pressure for the strata except for the confined aquifer at the early stage of *** st rata expand while the pore pressures *** inconsistency may be due to the large unloading in the confined aquifer at the early stage of *** arch comes into being owing to the constraint of the surrounding soils when the large unloading occurs in the confined aquifer;this can reduce the stratum compression and cause the expansion of the *** can be concluded that as the pumping continues,the decrease of the pore pressure dominates the vertical deformation and results in the soil compression in all strata.

关键词： pumping multi-layer strata numerical analysis groundwater drawdown stratum deformation

Soil fungi of three native tree species inhibit biomass production and shift biomass allocation of invasive Mikania micrantha Kunth

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Science Bulletin 2013年第7期58卷 757-765页

作者： GAO Lei ZAN QiJie li mingguang GUO Qiang HU liang JIANG Lu ZHOU Sheng liU HaiJun State Key Laboratory of Biocontrol Sun Yat-sen University Guangdong Key Laboratory of Plant Resources Shenzhen Wild Animal Rescue Center School of life Sciences Shenzhen University Shenzhen Wildlife Protecting Administration 6. School of Geographical Science and Planning Sun Yat-sen University

Soil microbes contribute to native plant species successful resistance against invasive *** native tree species,Heteropanax fragrans (HF),Cinnamomum burmanii (CB),and Macaranga tanarius (MT) were effective in controlling the notorious invasive vine Mikania micrantha (MM).Biomass production and allocation patterns (shoot/root biomass ratio (shoot/root)) are important indicators of MM climbing coverage and competitive light-capturing *** investigation was conducted to test the role of soil microbes associated with the three native tree species to inhibit MM biomass production and shift MM shoot/*** soils originating from preculture HF,CB,MT,and MM plots were collected separately for use as *** inocula were mixed with sterilized river sand at a 1:9 (w/w) ratio to grow *** fungicide carbendazim (methyl benzimidazol-2-ylcarbamate) was applied to half the treatments to kill pathogenic soil *** nutrient levels were established based on the natural soil nutrient concentration from a field stand invaded by *** were grown from seeds in a glasshouse,harvested 15 weeks after sowing,and separated into shoot and root *** showed that under interaction of soil origin and nutrient levels,MM biomass production was unchanged,but biomass allocation patterns were significantly *** biomass production grown in the three native tree soils under two nutrient levels was similar or higher than MM biomass production in MM conspecific soil,indicating the absence of species-specific pathogens that inhibited MM biomass production in native tree ***,in both conspecific and tree soils,MM biomass production was significantly reduced in the presence of pathogenic soil fungi,*** experienced significant fungal inhibition,demonstrating the pathogenic soil fungi promoted native tree resistence to *** exhibited decreased shoot biomass allocation when cultivated in native tree soil relative to MM conspecific soil under fie

关键词： biological control biotic resistance Cinnamomum burmanii Heteropanax fragrans invasion ecology Macaranga tanarius Mikania micrantha nutrient levels pathogenic fungi

Influence of The Belt and Road Initiative on Oil and Gas Infrastructure

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China Oil & Gas 2016年第2期23卷 23-29页

作者： Jiang Xinmin li mingguang Sun Ruihao Energy Research Institute of National Development and Reform Commission

China has proposed the ＂Belt and Road Initiative （B＆R）＂ in 2013. One its core strategies is international oil/gas cooperation. This paper addresses the status quo of cooperation on oil/gas infrastructure with countries along the line of ＂B＆R＇, anticipahs the cooperatiorl prospect. On this basis, the author analyzes China＇s advantages and cooperation basis in this domain, conceives the practical way of cooperation on oil/gas infrastructure with countries along the line of ＂B＆R＇. This paper also elaborates on tlre potential risks, risk evaluation criteria and risk corr trol in oil/gas infrastructu re cooperation with countries tries along tire line of ＂B＆R＂.

关键词： Belt and Road Initiative Oil/gas infrastructure Oil/gas international cooperation Market risk Countermeasures