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Journal of Rare Earths 2021年第2期39卷 113-120页

作者： Xiangjie Tang qi Liu Chuangyu Wei Xuehui lv Zhicheng Jin Yanli Chen Jianzhuang Jiang School of Materials Science and Engineering College of ScienceChina University of Petroleum(East China)Qingdao 266580China Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials Department of ChemistryUniversity of Science and Technology BeijingBeijing 100083China

In recent years,sandwich-type rare earth tetrapyrrole derivatives,have attracted more and more attention as material for conductimetric *** have not only great chemical stability and processability,but also flexible molecular structure,which is a key to adjustable semiconductor *** this mini review,we focus mainly on the development of tetrapyrrolato-rare earth sandwich-type complexes as the semiconducting active layer in the gas sensors published in the last ten years(2010-2020).The main part includes two *** the single component gas sensing of sandwich rare earth tetrapyrrole complexes,we describe the influence factors of the single-component semiconducting active layer on the sensing performance of tetrapyrrolato-rare earth sandwich-type complexes,including substituents,central metals and π-conjugate *** the multi-component gas sensors,the synergistic effect between tetrapyrrolato-rare earth sandwich-type complex and other materials on improving sensitivity and conductivity has been discussed briefly.

关键词： Sandwich-type rare earth tetrapyrrole complex Phthalocyanine Gas sensor Rare earths

A new algorithm for reconstructing the three-dimensional flow field of the oceanic mesoscale eddy

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Chinese Physics B 2021年第12期30卷 175-181页

作者： chao Yan Jing Feng Ping-lv Yang Si-Xun Huang Institute of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic AdministrationHangzhou 310012China Basic Department Nanjing Tech UniversityPujiang InstituteNanjing 211112China

A new algorithm for reconstructing the three-dimensional flow field of the oceanic mesoscale eddies is proposed in this paper,based on variational ***,with the numerical differentiation Tikhonov regularizer,we reconstruct the continuous horizontal flow field on discrete grid points at each layer in the oceanic region,in terms of the horizontal flow field ***,benefitting from the variational optimization analysis and its improvement,we reconstruct a three-dimensional flow field under the constraint of the horizontal flow and the vertical *** results of simulation experiments validate that the relative error of the new algorithm is lower than that of the finite difference method in the case of high grid resolution,which still holds in the case of unknown observational errors or in the absence of vertical velocity boundary ***,using the reanalysis horizontal data sourcing from SODA and the proposed algorithm,we reconstruct three-dimensional flow field structure for the real oceanic mesoscale eddy.

关键词： mesoscale eddy numerical differentiation Tikhonov regularization variational optimization analysis

Local failure mechanism of sand-blocking fence in latticed dune along desert roads

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Journal of Mountain Science 2024年第2期21卷 526-537页

作者： LI Liangying lv Lele LI qi WANG Zhenqiang YANG Youhai YIN Wenhua School of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Ningxia Highway Survey and Design Institute Co Ltd Yinchuan 750001China

The latticed dunes in the Tengger Desert are widely distributed,and the sand-blocking fence placed here are highly susceptible to local failure due to complex wind-sand activities,posing a serious threat to the safe operation of the *** explore the local failure mechanism of sand-blocking fence in the latticed dune area,the local failure of sand-blocking fence in the latticed dune areas along the Wuhai-Maqin Highway in China was *** the first main ridge of the latticed dune as the placement location,the structure of the wind-sand flow field of sand-blocking fence placed at top,the bottom and the middle of windward slope was analyzed by Computational Fluid Dynamics(CFD).The results show that when placed at top of the first main ridge,the wind speed near the sand-blocking fence is the highest,up to 15.23 m/***,the wind load strength on the sand barrier is correspondingly larger,up to 232.61 N∙*** the strength of material continues to decrease,the nylon net is prone to *** roots of the angle steel posts are susceptible to hollowing by vortex action,which can cause sand-blocking fence to fall over in strong wind *** placed at the bottom of windward slope,wind speed drop near sand-blocking fence is greatest,with the decrease of 12.48-14.32 m/s compared to the original wind *** is highly likely to lead to large-scale deposition of sand particles and burial of the sand-blocking *** placed in the middle of windward slope,sand-blocking fence is subjected to less wind load strength(168.61N∙m-2)and sand particles are mostly deposited at the bottom of windward slope,with only a small amount of sand accumulating at the root of sand-blocking *** on field observations and numerical modelling results,when the sand-blocking fence is placed in latticed dune area,it should be placed in the middle of the windward slope of the first main ridge as a matter of *** the sand-blocking fence should be placed

关键词： Latticed dune Sand-blocking fence Local failure Numerical simulation Desert roads

Instability mechanism and control technology of soft rock roadway affected by mining and high confined water

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International Journal of Mining Science and Technology 2015年第4期25卷 573-580页

作者： Li Guichen Jiang Zuohan lv Chuangxin Huang chao Chen Gui Li Mingyuan School of Mines Key Laboratory of Deep Coal Resource Mining Ministry of Education China University of Mining & Technology Huaibei Coal Mining Limited Company Huaibei Pingyuan Soft Rock Engineering Company

Based on deformation and failure characteristics of the second belt conveyor roadway at level II of Zhuxianzhuang coal mine, laboratory experiments, numerical calculation and field test were adopted to analyze the composition and microstructure of mudstone, the law of mudstone hydration and its strength weakening induced by water, the characteristics of surrounding rock deformation and failure under the action of confined water. Results showed that montmorillonite clay minerals accounted for as much as 76% of mudstone, with a large number of pores existing in the microstructure. Besides, as the molecular structure of montmorillonite changed, mudstone microstructure damage occurred with the macroscopic manifestation of its theological instability. Weakening degree of confined water on residual strength of mudstone was almost 50%. The instability mechanism of soft rock roadway caused by high confined water is that surrounding rock circulates the process of ＂fracture-seepage-mud ding-closed＂ twice, which weakens its strength and leads to roadway instability. A combined support technology, namely the, ＂high-toughness sealing layer ＋ hollow grouting cables ＋ full-length anchoring bolts with deep borehole＂ was proposed. Based on field observation, the soft rock roadway was controlled effectively, which also verified the effectiveness of new control technology for surrounding rock.

关键词： High confined water Soft rock roadway Instability mechanism Control technology

Rigid Dysprosium(Ⅲ)Single-Molecule Magnets Exhibit Preserved Superparamagnetism in Solution

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Chinese Journal of Chemistry 2022年第5期40卷 563-570页

作者： Xiali Ding qiancheng Luo Yuanqi Zhai Xufeng Zhang Yi lv Xinliang Zhang chao Ke chao Wu Yanzhen Zheng Frontier Institute of Science and Technology(FIST) State Key Laboratory of Mechanical Behavior for MaterialsMOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed MatterXi'an Key Laboratory of Sustainable Energy and Materials ChemistrySchool of Chemistry and School of PhysicsXi'an Jiaotong University99 Yanxiang RoadXi'anShaanxi710054 China Department of Hepatobiliary Surgery and The First Affiliated Hospital of Xi'an Jiaotong University 277 West Yanta RoadXi'anShaanxi710061 China Department of Spine Surgery Honghui HospitalXi'an Jiaotong University76 Nanguo RoadXi'anShaanxi710054 China Department of Orthopaedics and Trauma Hong Hui HospitalCollege of MedicineXi'an Jiaotong University555 East Youyi RoadXi'anShaanxi710054 China

Molecules with long preserved magnetic moments are perceived as the smallest units for storing bytes,which could bring a new revolution for information ***,the rational design of such molecules remains *** two rigid adamantanol ligand based dysprosium(III)complexes([Dy(1-AdO)_(2)(py)_(5)]BPh_(4)-1 and[Dy(2-AdO)_(2)(py)_(5)]BPh_(4)-2)with pentagonal-bipyramidal coordination geometry and local D5h symmetry were successfully prepared,which display excellent single-molecule magnet(SMM)behavior(U_(eff)≈1835 K,T_(B)_(ZFC)≈24 K,T_(B)^(100s)≈17 K and T_(B)^(H)=23 K for 1;U_(eff)≈1756 K,T_(B)^(ZFC)≈20 K,T_(B)^(100s)≈16 K and T_(B)^(H)=23 K for 2)due to the much weakened vibration in low energy ***,the large energy barriers and high blocking temperatures for these two complexes in solid states are well preserved in *** is never observed in previous studies of SMMs,indicating that the adamantanol is rigid and can be introduced to make the composed molecules stable enough to maintain the solid state magnetic property in solution.

关键词： Molecularmagnets Lanthanide D_(sh)-symmetry Superparamagnetism Solution

Research on the Follow-Up Control Strategy of Biaxial Fatigue Test of Wind Turbine Blade Based on Electromagnetic Excitation

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Energy Engineering 2023年第10期120卷 2307-2323页

作者： Wenzhe Guo Leian Zhang chao lv Weisheng Liu Jiabin Tian School of Mechanical Engineering Shandong University of TechnologyZibo255049China Engineering and Technology Department CRRCWind Power(Shandong)Co.Ltd.Jinan250104China Testing Center Lianyungang Zhongfulianzhong Composite Material Group Co.Ltd.Lianyungang222000China

Aiming at the drift problem that the tracking control of the actual load relative to the target load during the electromagnetic excitation biaxial fatigue test of wind turbine blades is easy to drift,a biaxial fatigue testingmachine for electromagnetic excitation is designed,and the following strategy of the actual load and the target load is studied.A Fast Transversal Recursive Least Squares algorithm based on fuzzy logic(Fuzzy FTRLS)is proposed to develop a fatigue loading following dynamic strategy,which adjusts the forgetting factor in the algorithmthrough fuzzy logic to overcome the contradiction between convergence accuracy and convergence speed and solve the phenomenon of amplitude overshoot and phase lag of the actual load relative to the target *** with the previous research results,a simulation model was constructed to verify the strategy’s *** tests were carried out to verify its follow-up *** results showthat the tracking error of flapwise and edgewise direction iswithin 4%,which has better robustness and dynamic and static performance than the traditional Recursive Least Squares(RLS)algorithm.

关键词： Wind turbine blades biaxial fatigue loading tracking control fuzzy FTRLS

Operation strategy and energy-saving of the solar lighting/heating system through spectral splitting

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Energy and Built Environment 2023年第3期4卷 270-280页

作者： chao Shen Kaijie Zheng Changyun Ruan Guoquan lv Mahroo Eftekhari School of Architecture Harbin Institute of TechnologyKey Laboratory of Cold Region Urban and Rural Human Settlement Environment Science and TechnologyMinistry of Industry and Information TechnologyHarbin 15000China School of Architecture Building and Civil EngineeringLoughborough UniversityLoughboroughUK

The performance of a solar lighting and heating system(SLHS)based on the spectral splitting effect of nanofluids is presented in this *** through nanofluids would split the sunlight spectrum into different wavelength,and then introduce the visible light into the offices for lighting and absorb infrared energy to generate hot *** Energy Plus software was used to analyze the energy consumption of typical office building located in the city of Harbin in China coupled with *** on the simulation results two lighting zones were identified in the offices and the optimal lighting control strategy was developed for a full *** performance models of SLHS with different light-receiving areas of 10 m^(2)and 40 m^(2)were simulated and validated using the existing experimental *** overall energy-saving of the offices over a full year were analyzed using the validated *** demonstrated that for SLHS with the area of 40 m^(2),the rate of the energy saving in the offices due to lighting and hot water systems were 58.9%,and 19.3%,*** system also had the additional benefit of reducing the cooling load of the air conditioning system during summer period together with improving the quality of the indoor environment resulting in better health and productivity of the occupants.

关键词： Office building Energy consumption Solar lighting/heating Lighting control strategy Energy-saving benefits

Increased intestinal permeability in pathogenesis and progress of nonalcoholic steatohepatitis in rats

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World Journal of Gastroenterology 2007年第11期13卷 1732-1736页

作者： Xi Jin chao-Hui Yu Guo-Cai lv You-Ming Li Digestive Department of the First Affiliated Hospital Medical School Zhejiang University Hangzhou 310003 Zhejiang Province China Clinical Laboratory of the First Affiliated Hospital Medical School Zhejiang University Hangzhou 310003 Zhejiang Province. China

AIM： To investigate whether increased intestinal permeability contributes to the pathogenesis and progress of nonalcoholic steatohepatitis by observing its dynamic change in rat models. METHODS： Rat models of nonalcoholic steatohepatitis were established by giving a fat-rich diet. The rats were sacrificed at wk 8, 12 and 16 during the study. Rats fed with normal diet were taken as control. Plasma D-lactate, plasma diarnine oxidase, serum lipids and liver transarninases were measured in blood of the femoral artery. Hepatic steatosis and inflammation were assessed by haematoxylin-eosin staining. RESULTS： A rat model of nonalcoholic steatohepatitis was established successfully. Plasma D-lactate level in model group at wk 8, 12 and 16 and diarnine oxidase level in model group at wk 12, 16 increased significantly compared with those in control group. There were notable differences of D-lactate and diarnine oxidase level in model group between wk 8 and 12 as well as between wk 12 and 16. Serum lipids, liver transaminases and liver injury also increased with disease development CONCLUSION： Increased intestinal permeability caused by intestinal bacterial overgrowth and endotoxin-induced intestinal destruction exists in rats with nonalcoholic steatohepatitis, which may partially explain the pathogenesis and progress of this disease.

关键词： Nonalcoholic steatohepatitis Intestinal permeability D-lactate Diamine oxidase

Semiparametric Model Averaging for Ultrahigh-Dimensional Conditional Quantile Prediction

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Acta Mathematica Sinica,English Series 2023年第6期39卷 1171-1202页

作者： chao Hui GUO Jing lv Hu YANG Jing Wen TU Chen Xiao TIAN School of Mathematical Sciences Chongqing Normal UniversityChongqing 401331P.R.China School of Mathematics and Statistics Southwest UniversityChongqing 400715P.R.China College of Mathematics and Statistics Chongqing UniversityChongqing 401331P.R.China College of Finance University of International Business and EconomicsBeijing 100020P.R.China

In this paper,we develop a flexible semiparametric model averaging marginal regression procedure to forecast the joint conditional quantile function of the response variable for ultrahighdimensional ***,we approximate the joint conditional quantile function by a weighted average of one-dimensional marginal conditional quantile functions that have varying coefficient ***,a local linear regression technique is employed to derive the consistent estimates of marginal conditional quantile ***,based on estimated marginal conditional quantile functions,we estimate and select the significant model weights involved in the approximation by a nonconvex penalized quantile *** some relaxed conditions,we establish the asymptotic properties for the nonparametric kernel estimators and oracle estimators of the model averaging *** further derive the oracle property for the proposed nonconvex penalized model averaging ***,simulation studies and a real data analysis are conducted to illustrate the merits of our proposed model averaging method.

关键词： Kernel regression model averaging oracle property penalized quantile regression ultrahigh-dimension data

Solvent and guest-binding-controlled chiroptical inversion of molecular devices based on pseudo[1]catenane-type pillar[5]arene derivatives

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Chinese Chemical Letters 2024年第1期35卷 280-284页

作者： Yongjun lv chao Xiao Jingyu Ma Dayang Zhou Wanhua Wu Cheng Yang College of Chemical Engineering Sichuan University of Science&EngineeringZigong 643000China College of Chemistry Sichuan UniversityChengdu 610064China Zhejiang NHU Pharmeceutical Co. Ltd.Shaoxing 312000China Comprehensive Analysis Center ISIROsaka UniversityOsaka 567-0047Japan

Four pillar[5]arene-based bicyclic compounds,so-called molecular universal joint(MUJ),were synthesized by incorporating a bisamide ring containing N,O,or S-heteroatom groups,which served as stimuli-responsive chiroptical molecular *** structure of MUJ was confirmed by 1H NMR spectra and single-crystal X-ray diffraction analysis,and their planar-chiral enantiomers were successfully *** inversion behaviors from in to out configurations triggered by temperature,solvent,and guest complexation were investigated by circular dichroism *** inversion could be realized in the presence of adiponitrile in certain solvents due to the solvation effects on the side ring and the threading of the guest into the pillar[5]arene ***,the stronger self-included interactions between the cavity and the inside ring of certain MUJs led to inhibition of the switching.

关键词： Pillararene N,O,S-containg ring Bicycles Solvation Chirality inversion