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Damage smear method for rock failure process analysis

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第6期11卷 1151-1165页

作者： G.Li X.F.Cheng h.pu C.A.Tang state key laboratory of coastal and offshore engineering dalian university of technologydalian116024china state key laboratory for geomechanics and deep underground engineering china university of mining and technologyxuzhou221116china ocean engineering joint research center of dut-uwa dalian university of technologydalian116024china

Damage smear method(DSM)is adopted to study trans-scale progressive rock failure process,based on statistical meso-damage model and finite element *** statistical approach is utilized to reflect the mesoscopic rock *** constitutive law of representative volume element(RVE)is established according to continuum damage mechanics in which double-damage criterion is *** damage evolution and accumulation of RVEs are used to reveal the macroscopic rock failure *** single RVE will be represented by one unique *** initiation,propagation and coalescence of meso-to macro-cracks are captured by smearing failed *** above ideas are formulated into the framework of the DSM and programed into self-developed rock failure process analysis(RFPA)*** laboratory-scale examples are conducted and the well-known engineering-scale tests,*** Energy of Canada Limited’s(AECL’s)Underground Research Laboratory(URL)tests,are used for *** shows that the simulation results match with other experimental results and field observations.

关键词： Failure process Smear method Meso-damage Finite element method (FEM) Rock failure process analysis (RFPA)

Potassium ions and cyano group modified g-C3N4 for effective generation of h2O2 through two-electron oxygen reduction

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Science China Chemistry 2025年第1期68卷 192-200页

作者： Dongying Wang Shulan pu Yongmin Chen Ke Lei Yujie Duan Linjiao Mao Xuhui Zeng Xi Luo Yuntao Zhang Yuqin Dong Jin Zhong Zhang Yan Sun School of Mechanical Engineering Chengdu University Department of Chemistry and Biochemistry University of California

Potassium ions （K+） doped graphitic carbon nitride （g-C3N4） was prepared by a thermal etching method using potassium hydroxide （KOh） as an ion *** transform infrared spectroscopy （FTIR） and X-ray photoelectron spectroscopy （XPS）results showed that the generation of the cyano group was detected while introducing K+.Under simulated sunlight irradiation,the sample with a K+doping amount of 10%showed the highest hydrogen peroxide （h2O2） generation rate of2,140.2μmol *** apparent quantum yield （AQY） at 400 nm and the solar-to-chemical conversion （SCC） are 4.35%and1.23%,respectively.K+acted as a bridge between g-C3N4layers,which enhanced charge transfer ***,the cyano group enhanced the adsorption capacity of protons （h+） and promoted the yield of *** catalyst exhibited excellent photocatalytic stability based on four-cycle *** addition,a mechanism study showed that superoxide radicals （·O2-）were the most important active species in the reaction *** production of h2O2was achieved through consecutive single-electron *** study deepens the understanding of the oxygen reduction reaction process and opens up a new venue for improving h2O2generation.

关键词： photocatalysis hydrogen peroxide oxygen reduction reaction potassium doping cyano group

Chiral phosphoramidite ligand-modulated palladium auto-tandem catalysis for asymmetric dehydrogenative dienylation of imines with α-alkenes

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Science China Chemistry 2025年

作者： Zhong-Sheng Nong hao-Fan Qian Ying-Chun Chen pu-Sheng Wang Liu-Zhu Gong hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of China Key Laboratory of Drug Targeting and Drug Delivery System (Sichuan University) Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of Pharmacy Sichuan University School of Materials and Chemistry Southwest University of Science and Technology

The development of efficient processes allowing rapid access to complex chiral molecules from easily available alkenes is a long-term pursuit in the synthetic chemistry community. Transition metal-catalyzed asymmetric functionalization of allylic C–h bond represents a unique alternative toward this goal. however, enantioselective dehydrogenative transformation of olefins to value-added optically enriched molecules remains yet to be discovered. here, we report a highly enantioselective dehydrogenative dienylation of imines with unactivated α-alkenes driven by the synergistic action of palladium complex and carboxylic acid. Chiral phosphoramidite ligands turned out to be superior in modulating the performance of palladium autotandem catalysis and allowed a broad range of α-alkenes and imines to be transformed into chiral dienylamines. Mechanistic studies suggest that the dienes could be in situ generated from α-alkenes through a palladium(0)-mediated dehydrogenative process in the presence of excess benzoquinone oxidants, and then participated in the Pd-chiral phosphoramidite-catalyzed intermolecular vinylogous-type addition to the imines activated by the carboxylic acid co-catalyst. Notably, the second β-h elimination occurring in the dienylation event might be the turnover-limiting step.

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Shallow sediment transport flow computation using time-varying sediment adaptation length

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International Journal of Sediment Research 2014年第2期29卷 171-183页

作者： jaan hui pu Khalid hUSSAIN Song-dong ShAO Yue-fei hUANG School of Engineering and Informatics University of Bradford West Yorkshire BD7 1DPUK.Lecturer School of Engineering University of Bradford West Yorkshire BD7 1 DPUK.Head Department of Civil and Structure Engineering University of Sheffield Sheffield S1 3JDUK Senior Lecturer State Key Laboratory of hydro-Science and Engineering Tsinghua University

Based on the common approach,the adaptation length in sediment transport is normally estimated astemporally ***,this approach might not be theoretically justified as the process of reaching the sediment transport equilibrium stage is affected by the flow conditions in time,especially for fast moving flows,such as scour-hole developing *** this study,the two-dimensional(2D) shallow water formulation together with a sediment continuity-concentration(SCC) model were applied to flow with mobile sediment boundary.A timevarying approach was proposed to determine the sediment transport adaptation length to simulate the sediment erosion-deposition *** proposed computational model was based on the Finite Volume(FV) *** Monotone Upwind Scheme of Conservative Laws(MUSCL)-hancock scheme was used with the harten Lax van Leer-contact(hLLC) approximate Riemann solver to discretize the FV *** the flow applications of this paper,a highly discontinuous dam-break,fast sediment transport flow was used to calibrate the proposed timevarying sediment adaptation length *** the calibrated model was further applied to two separate experimental sediment transport flow applications documented in the literature,i.e.a highly concentrated sediment transport flow in a wide alluvial channel and a sediment aggradation *** agreement with the experimental data were obtained with the proposed model *** tests prove that the proposed model,which was calibrated by the discontinuous dam-break bed scouring flow,also performed well to represent rapid bed change and steady sediment mobility conditions.

关键词： Finite volume model harten Lax van Leer-contact solver Monotonic upwind scheme Sediment transport Shallow water model Time-varying sediment adaptation length

Submerged flexible vegetation impact on open channel flow velocity distribution: An analytical modelling study on drag and friction

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Water Science and Engineering 2019年第2期12卷 121-128页

作者： jaan h. pu Awesar hussain Ya-kun Guo Nikolaos Vardakastanis Prashanth R. hanmaiahgari Dennis Lam Faculty of Engineering and Informatics University of BradfordBradford BD7 1DPUK Department of Civil Engineering Indian Institute of TechnologyKharagpur 721302India

In this paper,an analytical model that represents the streamwise velocity distribution for open channel flow with submerged flexible vegetation is *** the present vegetated flow modelling,the whole flow field has been separated into two layers vertically: a vegetated layer and a non-vegetated free-water *** the vegetated layer,an analysis of the mechanisms affecting water flow through flexible vegetation has been *** the non-vegetated layer,a modified log-law equation that represents the velocity profile varying with vegetation height has been *** on the studied analytical model,a sensitivity analysis has been conducted to assess the influences of the drag (CD) and friction (Cf ) coefficients on the flow *** investigated ranges of CD and Cf have also been compared to published *** findings suggest that the CD and Cf values are non-constant at different depths and vegetation densities,unlike the constant values commonly suggested in *** phenomenon is particularly clear for flows with flexible vegetation,which is characterised by large deflection.

关键词： Analytical model Flexible vegetation Flow velocity Friction Drag Submerged vegetation

槲皮素治疗非小细胞肺癌的网络药理学分析及细胞实验验证

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食品工业科技 2025年第2期46卷 334-342页

作者：王翊蒲晓芳山东中医药大学药学院山东中医药大学管理学院

目的：探究槲皮素治疗非小细胞肺癌（NSCLC）的潜在机制，并结合分子生物学实验验证。方法：通过SwisTargetPrediction和DrugBank数据库筛选槲皮素的靶点，通过GeneCards、TTD数据库收集NSCLC的疾病靶点，进行靶点映射获得槲皮素治疗NS... 详细信息

目的：探究槲皮素治疗非小细胞肺癌（NSCLC）的潜在机制，并结合分子生物学实验验证。方法：通过SwisTargetPrediction和DrugBank数据库筛选槲皮素的靶点，通过GeneCards、TTD数据库收集NSCLC的疾病靶点，进行靶点映射获得槲皮素治疗NSCLC的靶点，应用STRING数据库获取蛋白-蛋白相互作用（PPI）网络并进行分析，使用Cytoscape 3.7.2进行可视化；利用DAVID数据库进行靶点富集，进行基因本体论分析（GO）和京都基因与基因组百科全书分析（KEGG）。采用分子对接对核心靶点进行验证，并使用PLIP平台分析结合位点力学数据。通过细胞实验评估槲皮素对A549细胞增殖的影响，并利用qRT-PCR和Western blot对核心靶点进行验证。结果：网络药理学研究显示，槲皮素能够调控126个靶点，潜在治疗NSCLC的靶点有49个，核心通路为PI3K-Akt信号通路，核心靶点为PI3K、Akt、GSK-3β。分子对接实验初步发现，槲皮素与3个核心靶点均能产生强烈结合力。细胞实验结果显示，槲皮素低、中、高剂量组干预72 h后均能够显著抑制A549细胞的增殖活力（P<0.01），并下调PI3K、Akt、GSK-3β的mRNA表达水平（P<0.05）以及蛋白表达趋势。结论：本研究分析预测了槲皮素治疗NSCLC的潜在活性机制，通过实验验证发现槲皮素可能通过抑制PI3K/Akt/GSK-3β信号通路发挥抗癌作用。

关键词：槲皮素非小细胞肺癌网络药理学分子对接 PI3K/Akt/GSK-3β信号通路

来源：博看期刊

Interface effect on the giant magnetoresistance for different magnetic multilayers systems

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Chinese Science Bulletin 1997年第9期42卷 729-733页

作者： Zhang, LY Sun, h Li, BZ pu, FK Institute of Physics Chinese Academy of Sciences Beijing China State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing China

ThE giant magnetoresistance(GMR)effect in magnetic multilayer has been the subject of in-tense investigation since its *** theories,including semiclassical theoryand quantum theory,have been developed to deal with the... 详细信息

关键词： magnetic multilayer interface effect giant magnetoresistance Anderson model.

Population-level performance of Arabidopsis thaliana (L.) heynh in dense monocultures

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Journal of Plant Ecology 2020年第2期13卷 241-246页

作者： Susanna Vain Iris Gielen jaan Liira Kristjan Zobel Department of Botany University of Tartu40 Lai St.51005 TartuEstonia hugo Treffner Gymnasium 12 Munga St.51007 TartuEstonia

Aims Very little is known about the performance of non-agricultural plant species in monocultures,even though nearly all agricultural species have experienced the transition from multi-species environments to dense monospecific stands during the breeding *** the light of recent work that highlighted the possibility that the weedy species Arabidopsis thaliana can offer novel insight into crop breeding,we aimed to test the effect of sowing density on group and individual performance in different photoperiod environments in *** We studied the performance of *** Cvi-0 *** choice of Cvi-0 was based on a preliminary experiment in which plants of Cvi-0 ecotype exhibited high competitive *** densities used were 17.6,8.8,4.4,2.2 and 1.1 cm^(2) per plant and photoperiod environments 12 or 16 h of day *** Findings In this experiment,populations attained constant total seed yield for all *** interaction effect occurred,as at high sowing density and at longer day length plants produced heavier seeds,whereas at shorter day length seed weight was negatively related to plant *** results shed light on different strategies that annual plants can adopt when they face intense intraspecific competition,and could help to offer new perspectives for breeding crops with enhanced group performance.

关键词： Arabidopsis thaliana constant final yield intraspecific competition monoculture photoperiod

PREDICTION OF MAXIMUM SCOUR DEPTh AROUND LARGE DIAMETER CYLINDER UNDER ThE EFFECTS OF BOTh WAVE AND CURRENT

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Journal of hydrodynamics 2005年第1期17卷 74-79页

作者： LILin-pu CUILi SchoolofCivilandhydraulicEngineering~DalianUniversityofTechnology Dalian116024china

Physical model tests were counducted to predict local scour and maximum scour depth around the large diameter cylinders located in the (sand) seabed under the action of both wave and current . According to the result of tests, an analysis was made on all the factors influencing the scour. The results shows that for the seabed with relative fine grains in shallow water (0.07h/L≤0.28),when the relative diameter D/L of the cylinder is within 0.3 0.7,the main effective scour factors around the cylinder in the seabed are diameter D of the cylinder, the wave height h, the wave length L, the velocity V c  of the current and the parameters related to the seabed soil texture. The main parameters influecing the maximum scour depth were analyzed, and the test data were syntherized, to obtain the formula predicting the scour depth around the large diameter cylinder under the of both wave and current.

关键词： offshore engineering the effects of both wave and current large diameter cylinder local scour