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An efficient probabilistic design approach for tunnel face stability by inverse reliability analysis

Geoscience Frontiers 2021年第5期12卷 374-383页

作者： Jian Ji Zheming Zhang Zhijun Wu Jiacheng Xia Yongxin Wu qing lüc Key laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjingChina School of civil Engineering Wuhan UniversityWuhanChina c College of Civil EngineeringZhejiang UniversityHangzhouChina

In order to maintain the safety of underground constructions that significantly involve geo-material uncertainties,this paper delivers a new computation framework for conducting reliability-based design(RBD)of shallow tunnel face stability,utilizing a simplified inverse first-order reliability method(FORM).The limit state functions defining tunnel face stability are established for both collapse and blow-out modes of the tunnel face failure,respectively,and the deterministic results of the tunnel face support pressure are obtained through three-dimensional finite element limit analysis(FElA).Because the inverse reliability method can directly capture the design support pressure according to prescribed target reliability index,the computational cost for probabilistic design of tunnel face stability is greatly *** comparison with Monte carlo simulation results,the accuracy and feasibility of the proposed method are ***,this study presents a series of reliability-based design charts for vividly understanding the limit support pressure on tunnel face in both cohesionless(sandy)soil and cohesive soil stratums,and their optimal support pressure ranges are *** results show that in the case of sandy soil stratum,the blowout failure of tunnel face is extremely unlikely,whereas the collapse is the only possible failure *** parametric study of various geotechnical uncertainties also reveals that ignoring the potential correlation between soil shear strength parameters will lead to over-designed support pressure,and the coefficient of variation of internal friction angle has a greater influence on the tunnel face failure probability than that of the cohesion.

关键词： Tunnel face stability Support pressure Finite element limit analysis Inverse reliability analysis Probabilistic design

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High performance of(KxNa1-x)0.98li0.02(Nb0.82-yTa0.18Sby)O3 lead-free piezoelectric ceramics

High performance of(KxNa1-x)0.98Li0.02(Nb0.82-yTa0.18Sby)O3 ...

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2011年全国压电和声波理论及器件应用研讨会

作者： Y.Gao,J.l.Zhang,~* F.Q.Guo,Y.l.qing and c.l.Wang School of Physics,State Key laboratory of crystal Materials.Shandong University,Jinan,P.R.china

lead-free piezoelectric materials that can replace the current Pb(Zr,Ti)03-based piezoelectric ceramics have attracted much attention in recent years from the viewpoint of environmental *** this presentation,we will report the study result obtained in a series of(KNali(NbTaSb)O ceramics,which are prepared by the conventional solid-state reaction *** has been found that crystalline structure changes from orthorhombic

关键词： (K,Na)NbO3-based ceramics Phase coexistence Piezoelectric properties Temperature stability

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Ideal Bi-Based Hybrid Anode Material for Ultrafast charging of Sodium-Ion Batteries at Extremely low Temperatures

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NANO-MIcRO lETTERS 2025年第1期17卷 1-16页

作者： Bai, Jie Jia, Jian Hui Wang, Yu Yang, chun cheng Jiang, qing Jilin Univ Key Lab Automobile Mat Sch Mat Sci & Engn Minist Educ Changchun 130022 Peoples R China

Metallic nanoparticles with excellent size controllability and high loading rate are obtained via ultrafast high temperature shock *** Bi/cNRs-15 electrode exhibits an unprecedented rate performance (237.9 mAh g-1 at 2 A g-1) at - 60 degrees c, while the energy density of the full cell can reach to 181.9 Wh kg-1 at - 40 degrees c.A novel strategy of high-rate activation is proposed to obtain high capacity and superior stability at low temperature by creating new active sites for interfacial reaction. Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at - 20 degrees c or lower. However, the key capability of ultrafast charging at ultralow temperature for SIBs is rarely reported. Herein, a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue, which is synthesized via a high temperature shock method. Such a hybrid shows an unprecedented rate performance (237.9 mAh g-1 at 2 A g-1) at - 60 degrees c, outperforming all reported SIB anode materials. coupled with a Na3V2(PO4)3 cathode, the energy density of the full cell can reach to 181.9 Wh kg-1 at - 40 degrees c. Based on this work, a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging low-temperature sodium-ion batteries

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Plasmonic tandem heterojunctions enable high-efficiency charge transfer for broad spectrum photocatalytic hydrogen production

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Journal of Energy chemistry 2025年第1期100卷 710-720页

作者： Wenxuan chen Xiu-qing Qiao Guo Hui Bojing Sun Dongfang Hou Meidi Wang Xueqian Wu Tao Wu Dong-Sheng li college of Materials and chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials China Three Gorges University Hubei Three Gorges laboratory college of chemistry and Materials Science and Guangdong Provincial Key Laboratory of Supramolecular Coordination Chemistry Jinan University

Rational engineering of semiconductor photocatalysts for efficient hydrogen production is of great significance but still challenging,primarily due to the limitations in charge transfer ***,a fascinating plasmonic tandem heterojunction with the hc-cdS/Mo2c@c heterostructure is aimfully prepared for effectively promoting the charge separation kinetics of the cdS photocatalyst via the synergistic strategy of phase junction,Schottky junction,and photothermal *** difference in atomic configuration between cubic-cdS （c-cdS） and hexagonal-cdS （h-cdS） leads to effective charge separation through a typical Ⅱ charge transfer mechanism,and plasmonic Schottky junction further extracts the electrons in the hc-cdS phase junction to realize gradient charge ***,the photothermal effect of Mo2c@c helps to expand the light absorption,accelerate charge transfer kinetics,and reduce the hydrogen evolution energy *** carbon layer provides a fast channel for charge transfer and protects the photocatalyst from *** a result,the optimized hc-cMc photocatalyst exhibits a significantly high photocatalytic H2production activity of 28.63 mmol/g/h and apparent quantum efficiency of 61.8%,surpassing most of the reported *** study provides a feasible strategy to enhance the charge transfer kinetics and photocatalytic activity of cdS by constructing plasmonic tandem heterogeneous junctions.

关键词： Heterojunctions lSPR Photocatalyst Phase junction Schottky junction Photothermal effect

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Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science china chemistry 2025年第1期 249-256页

作者： qing-Yun Fang chengyihan Gu Yinghan chen Wencheng Yan Yong liang Weipeng li chengjian Zhu Jie Han Jin Xie State Key laboratory of coordination chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green catalysis center College of Chemistry Zhengzhou University State Key laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-c(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

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Technologies for Efficient Use of Irrigation Water and Energy in china

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Journal of Integrative Agriculture 2013年第8期12卷 1363-1370页

作者： ZHANG qing-tao XIA qing clark c K liu Shu Geng Key laboratory for Urban Habitat Environmental Science and Technology School of Environment and EnergyPeking University Shenzhen Graduate School Department of civil and Environmental Engineering University of Hawaii at Manoa Department of Plant Sciences University of California

While the shortage of water and energy is a well-recognized worldwide natural resources issue, little attention has been given to irrigation energy efficiency. In this paper, we examine the potential energy savings that can be achieved by implementing improved irrigation technologies in china. The use of improved irrigation management measures such as a flow meter, irrigation scheduling, and/or regular maintenance and upgrades, typically reduces the amount of water pumped over the course of a growing season. The total energy saved by applying these improved measures could reach 20%, as compared with traditional irrigation methods. Two methods of irrigation water conveyance by traditional earth canal and low pressure pipeline irrigation （lPPI） were also evaluated. Our study indicated that lPPI could save 6.48x 109 kWh yr1 when applied to 11 chinese provinces. Also, the cOz emission was reduced by 6.72 metric tons per year. Among these 11 surveyed provinces, the energy saving potential for two provinces, Hebei and Shandong, could reach 1.45 x 109 kWh yr^-1. Using lPPI, potential energy saved and cO2 emissions reduced in the other 20 chinese provinces were estimated at about 2.97×109 kWh yr-1 and 2.69 metric tons per year, respectively. The energy saving potential for Heilongjiang, a major agriculture province, could reach 1.77× 109 kWh yr-1, which is the largest in all provinces. If lPPI is applied to the entire country, average annual energy saving of more than 9 billion kWh and average annual cO2 emission reduction of more than 9.0 metric tons could be realized. Rice is one of the largest users of the world＇s fresh water resources. compared with continuous flooding irrigation, intermittent irrigation （ITI） can improve yield and water-use efficiency in paddy fields. The total increments of net output energy and yield by ITI in paddy fields across china could reach 2.5× 1016 calories and l07 tons, respectively. So far only a small part of agricultural land in china ha

关键词： water and energy efficiency irrigation management low pressure pipeline irrigation energy saving potential,intermittent irrigation

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Hydrothermal Synthesis and crystal Structure of a Bivanadyl capped Keggin Polyoxomet alate[Zn(2,2'-bpy)_2(H_2O)]_2[HPMo_(12)O_(40)(VO)_2]

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chinese Journal of Structural chemistry 2005年第2期24卷 139-144页

作者： lüXiu-qing cHENJian-Xin lANTing-Yan HUANGYuan-Biao （collegeofchemistryandMaterialsScience FujianNormalUniversityFuzhouFujian350007China

A hydrothermal reaction of zinc acetate with molybdenum trioxide, vanadium pentoxide, phosphorus pentoxide and 2,2?-bpy (2,2?-bipyridine) led to the title compound [Zn(2,2?- bpy)2(H2O)]2[HPMo12O40(VO)2] 1. Single-crystal X-ray diffraction revealed that 1 (c40H36- N8O44PV2Zn2Mo12) crystallizes in the triclinic system, space group P1 with a = 11.881(2), b = 12.468(2), c = 12.622(2) ?, α = 71.333(8), β = 74.485(4), γ = 86.896(5)o, V = 1705.8(4) ?3, Mr = 2747.64, Z = 1, Dc = 2.675 g/cm3, μ = 3.201 mm-1, F(000) = 1309, S = 1.070, the final R = 0.0697 and wR = 0.1905 for 5368 observed reflections with I > 2σ(I). compound 1 is built on a mixed-metal bicapped [HPMo12V2O42] subunit covalently bonded to two [Zn(2,2?-bpy)2(H2O)]2+ clusters via terminal oxygen atoms of the capping V atoms. Each Zn atom is six-coordinated by four nitrogen atoms from two 2,2?-bpy ligands, one terminal oxygen atom from coordinated water mole- cule and another one from the capped {VO} unit.

关键词： Polyoxometalate crystal structure bivanadyl-capped polyoxoanion

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Output constrained Adaptive controller Design for Nonlinear Saturation Systems

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IEEE/cAA Journal of Automatica Sinica 2021年第2期8卷 441-454页

作者： Yongliang Yang Zhijie liu qing li Donald c.Wunsch the Key laboratory of Knowledge Automation for Industrial Processes of Ministry of Education School of Automation and Electrical EngineeringUniversity of Science and Technology BeijingBeijing 100083China the Department of Electrical and computer Engineering Missouri University of Science and TechnologyRollaMO 65409 USA

This paper considers the adaptive neuro-fuzzy control scheme to solve the output tracking problem for a class of strict-feedback nonlinear *** asymmetric output constraints and input saturation are *** asymmetric barrier lyapunov function with time-varying prescribed performance is presented to tackle the output-tracking error constraints.A high-gain observer is employed to relax the requirement of the lipschitz continuity about the nonlinear *** avoid the"explosion of complexity",the dynamic surface control(DSc)technique is employed to filter the virtual control signal of each *** deal with the actuator saturation,an additional auxiliary dynamical system is *** is theoretically investigated that the parameter estimation and output tracking error are semi-global uniformly ultimately *** simulation examples are conducted to verify the presented adaptive fuzzy controller design.

关键词： Asymmetric barrier lyapunov function input saturation Nussbaum function time-varying prescribed performance

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Stability of the Sarcin/Ricin domain of 28S RNA in rat ribosome under hydrostatic pressure

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chinese Science Bulletin 1998年第4期43卷 303-305页

作者： lü Biao li qing liu Wangyi Ruan Kangcheng chinese Acad Sci Shanghai Inst Biochem Shanghai 200031 Peoples R China

Under 2 100 bar of hydrostatic pressure, RNA N_glycosidase can still cleave the N_c bond of adenosine at position 4324 in R/S domain of 28S RNA in rat ribosome, demonstrating that high pressure has no effect on the te... 详细信息

关键词： hydrostatic pressure RNA N_glycosidase S/R domain.

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A Method for Evaluating the Maximum Bending Degree of Flexural Toppling Rock Masses Based on the Rock Tensile Strain-Softening Model

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Journal of Earth Science 2024年第4期35卷 1243-1253页

作者： Jiongchao Wang Jun Zheng Jichao Guo qing lü Jianhui Deng Department of civil Engineering Zhejiang UniversityHangzhou310058China center for Balance Architecture Zhejiang UniversityHangzhou310007China State Key laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China

Flexural toppling occurs when a series of layered rock masses bend towards their free *** is important to evaluate the maximum bending degree and the requirement of supports of flexural toppling rock mass to prevent rock mass cracking and even failure leading to a *** on the rock tensile strain-softening model,this study proposes a method for calculating the maximum curvature(c_(ppmax))of flexural toppling rock *** applying this method to calculate cppmax of 9 types of rock masses with different hardness and rock layer thickness,some conclusions are drawn:(1)the internal key factors affecting c_(ppmax)are E^(⋆)(E^(⋆)=E_(ss)/E_(0),where E_(0)and E_(ss)are the mean deformation moduli of the rock before and after reaching its peak tensile strength,respectively),the strainεt corresponding to the tensile strength of rock,and the thickness(h)of rock layers;(2)hard rock layers are more likely to develop into block toppling than soft rock layers;and(3)thin rock layers are more likely to remain in flexural toppling state than thick rock *** addition,it is found that c_(ppmax)for flexural toppling rock masses composed of bedded rocks such as gneiss is related to the tensile direction.

关键词： flexural toppling rock mass maximum bending degree strain-softening model curvature rock mechanics

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