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Energy mechanism of bolt supporting effect to fissured rock under static and dynamic loads in deep coal mines

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International Journal of Mining Science and Technology 2024年第3期34卷 371-384页

作者： Deyuan Fan xuesheng Liu Yunliang Tan Xuebin Li Shenglong yang College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Mining Disaster Prevention and Control Shandong University of Science and TechnologyQingdao 266590China National Energy Group Ningxia Coal Industry Co. Ltd.Yinchuan 753001China

The stability control of fissured rock is difficult,especially under static and dynamic loads in deep coal *** this paper,the dynamic mechanical properties,strain rate evolution and energy dissipation of fissured and anchored rocks were respectively obtained by SHPB *** was found that bolt can provide supporting efficiency-improving effect for fissured rock against dynamic disturbance,and this effect increased quadratically with decrease in anchoring ***,the energy dissipation mechanism of anchored rock was obtained by slipping ***,bolt energy-absorbing mechanism by instantaneous tensile-shear deformation was expressed based on material mechanics,which was the larger the anchoring angle,the smaller the energy absorption,and the less the contribution to supporting efficiency *** this basis,the functional relationship between energy dissipation of anchored rock and energy absorption of bolt was *** the coal-gangue separation system of Longgu coal mine as an example,the optimal anchoring angle can be determined as 57.5°–67.5°.Field monitoring showed fissured rock with the optimal anchoring angle,can not only effectively control the deformation,but also fully exert the energy-absorbing and efficiency-improving effect of bolt *** study provides guidance to the stability control and supporting design for deep engineering under the same or similar conditions.

关键词： Static and dynamic loads Anchored rock Energy absorption Anchoring angle Engineering verification

Verification of GRAPES unified global and regional numerical weather prediction model dynamic core

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Chinese Science Bulletin 2008年第22期53卷 3458-3464页

作者： yang xuesheng HU JiangLin CHEN DeHui ZHANG HongLiang SHEN XueShun CHEN JiaBin JI LiRen State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China National Meteorological Center Beijing 100081 China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Beijing 100029 China

During the past few years, most of the new developed numerical weather prediction models adopt the strategy of multi-scale technique. Therefore, China Meteorological Administration has devoted to developing a new generation of global and regional multi-scale model since 2003. In order to validate the performance of the GRAPES (Global and Regional Assimilation and PrEdiction System) model both for its scientific design and program coding, a suite of idealized tests has been proposed and conducted, which includes the density flow test, three-dimensional mountain wave and the cross-polar flow test. The density flow experiment indicates that the dynamic core has the ability to simulate the fine scale nonlinear flow structures and its transient features. While the three-dimensional mountain wave test shows that the model can reproduce the horizontal and vertical propagation of internal gravity waves quite well. Cross-polar flow test demonstrates the rationality of both for the semi-Lagrangian departure point calculation and the discretization of the model near the poles. The real case forecasts reveal that the model has the ability to predict the large-scale weather regimes in summer such as the subtropical high, and to capture the major synoptic patterns in the mid and high latitudes.

关键词：数值天气预报气象学天气预测气象分析

New generation of multi-scale NWP system (GRAPES):general scientific design

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Chinese Science Bulletin 2008年第22期53卷 3433-3445页

作者： CHEN DeHui XUE JiShan yang xuesheng ZHANG HongLiang SHEN XueShun HU JiangLin WANG Yu JI LiRen CHEN JiaBin State Key Laboratory of Server Weather Chinese Academy of Meteorological Sciences Beijing 100081 China National Meteorological Center Beijing 100081 China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100089 China

A new generation of numerical prediction system GRAPES (a short form of Global/Regional Assimilation and PrEdiction System) was set up in China Meteorological Administration (CMA). This paper focuses on the scientific design and preliminary results of the numerical prediction model in GRAPES, including basic idea and strategy of the general scientific design, multi-scale dynamic core, physical package configuration, architecture and parallelization of the codes. A series of numerical experiments using the real data with horizontal resolutions from 10 to 280 km and idealized experiments with very high resolution up to 100 m are conducted, giving encouraging results supporting the multi-scale application of GRAPES. The results of operational implementation of GRAPES model in some NWP centers are also presented with stress at evaluations of the capability to predict the main features of precipitation in China. Finally the issues to be dealt with for further development are discussed.

关键词：数值天气预报气象学天气预测 GRAPES

Amplified internal electric field of Cs_(2)CuBr_(4)@WO_(3-x)S-scheme heterojunction for efficient CO_(2)photoreduction

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Journal of Energy Chemistry 2024年第5期92卷 521-533页

作者： Zhijie Zhang xuesheng Wang Junyi Qian Jiayue Xu School of Materials Science and Engineering Shanghai Institute of TechnologyShanghai 201418China

Heterojunction construction,especially S-scheme heterojunction,represents an efficient universal strategy to achieve high-performance photocatalytic *** further performance stimulation of these well-designed heterojunctions,modulating the interfacial internal electric field(IEF)to steer dynamic charge transfer represents a promising ***,we realized the precise regulation of Fermi level(E_(F))of the oxidation semiconductor(mesoporous WO_(3-x))by tailoring the concentration of oxygen vacancies(V_(O)),maximizing the IEF intensity in Cs_(2)CuBr_(4)@WO_(3-x)(CCB@WO_(3-x))S-scheme *** augmented IEF affords a robust driving force for directional electron delivery,leading to boosted charge ***,the developed CCB@WO_(3-x)S-scheme heterojunction demonstrated outstanding photocatalytic CO_(2)reduction performance,with the electron consumption rate(Relectron)up to 390.34μmol g^(-1)h^(-1),which is 3.28 folds higher than that of pure *** in-depth analysis of the S-scheme electron transfer mode was presented via theoretical investigations,electron spin resonance(ESR),photo-irradiated Kelvin probe force microscopy(KPFM),and in-situ X-ray photoelectron spectroscopy(XPS).Finally,the CO_(2)photoconversion route was explored in detail using in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and DFT theoretical calculations.

关键词： Cs_(2)CuBr_(4) WO_(3-x) Oxygen vacancy S-scheme heterojunction Internal electricfield

林风眠-苏天赐-丁方:值得回望的三代精神传承

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南京艺术学院学报（美术与设计） 2010年第4期 97-101,96页

作者：杨学生解放军理工大学江苏南京210007

林风眠先生作为中国现代绘画的先驱者、现代艺术教育的奠基者与开拓者之一,桃李满天下,其中苏天赐及苏天赐的学生丁方在人格品行、艺术理想、精神追求方面与林风眠先生一脉相承。师承现象具体表现在师徒三代人都具有独立的知识分子的品... 详细信息

林风眠先生作为中国现代绘画的先驱者、现代艺术教育的奠基者与开拓者之一,桃李满天下,其中苏天赐及苏天赐的学生丁方在人格品行、艺术理想、精神追求方面与林风眠先生一脉相承。师承现象具体表现在师徒三代人都具有独立的知识分子的品格、内在的悲剧品格、辩证理性的思维与强烈的创造意识。林风眠-苏天赐-丁方三代人同心相映,师心不师迹。

关键词：林风眠-苏天赐-丁方艺术教育精神传承

Molybdenum and cadmium co-induce necroptosis through Th1/Th2 imbalance-mediated endoplasmic reticulum stress in duck ovaries

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Journal of Environmental Sciences 2024年第8期142卷 92-102页

作者： Ting Cui Xueyan Dai Huiling Guo Dianyun Wang Bingyan Huang Wenjing Pu xuesheng Chu Caiying Zhang Jiangxi Provincial Key Laboratory for Animal Health Institute of Animal Population HealthCollege of Animal Science and TechnologyJiangxi Agricultural UniversityNanchang 330045China

Cadmium(Cd)and excess molybdenum(Mo)pose serious threats to animal *** previous study has determined that Cd and/or Mo exposure can cause ovarian damage of ducks,while the specific mechanism is still *** further investigate the toxic mechanism of Cd and Mo co-exposure in the ovary,forty 8-day-old female ducks were randomly allocated into four groups for 16 weeks,and the doses of Cd and Mo in basic diet per kg were as follows:control group,Mo group(100 mg Mo),Cd group(4 mg Cd),and Mo+Cd group(100 mg Mo+4 mg Cd).Cadmium sulfate 8/3-hydrate(CdSO_(4)·8/3H_(2)O)and hexaammonium molybdate((NH_(4))_(6)Mo_(7)O_(24)·4H_(2)O)were the origins of Cd and Mo,*** the 16th week of the experiment,all ovary tissues were collected for the detection of related *** data indicated that Mo and/or Cd induced trace element disorders and Th1/Th2 balance to divert toward Th1 in the ovary,which activated endoplasmic reticulum(ER)stress and then provoked necroptosis through triggering RIPK1/RIPK3/MLKL signaling pathway,and eventually caused ovarian pathological injuries and necroptosis *** alterations of above indicators were most apparent in the joint *** all,this research illustrates that Mo and/or Cd exposure can initiate necroptosis through Th1/Th2 imbalance-modulated ER stress in duck ovaries,and Mo and Cd combined exposure aggravates ovarian *** research explores the molecular mechanism of necroptosis caused by Mo and/or Cd,which reveals that ER stress attenuation may be a therapeutic target to alleviate necroptosis.

关键词： Molybdenum Cadmium Th1/Th2 imbalance Endoplasmic reticulum stress Necroptosis Ovary

Effects of dexmedetomidine on emergence delirium and electroencephalogram during the recovery period in older patients undergoing lower limb orthopedic surgery: A randomized, double-blind, placebo-controlled clinical trial

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中华医学杂志(英文版) 2024年第16期137卷 1982-1984页

作者： Li Jun Ye Chenxuan Fang Panpan Qian Jing Shang Zixiang Liu xuesheng Department of Anaesthesiology The First Affiliated Hospital of Anhui Medical University Hefei Anhui China

A semi-implicit semi-Lagrangian global nonhydrostatic model and the polar discretization scheme

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Science China Earth Sciences 2007年第12期50卷 1885-1891页

作者： yang xuesheng1,CHEN JiaBin2,HU JiangLin1,CHEN DeHui1,SHEN XueShun1,ZHANG HongLiang1 1 State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,China 2 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics,Beijing 100029,China State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Beijing China

The Global/Regional Assimilation and PrEdiction System(GRAPES) is a newly developed global non-hydrostatic numerical prediction model,which will become the next generation medium-range opera-tional model at China Meteorological Administration(CMA).The dynamic framework of GRAPES is featuring with fully compressible equations,nonhydrostatic or hydrostatic optionally,two-level time semi-Lagrangian and semi-implicit time integration,Charney-Phillips vertical staggering,and complex three-dimensional pre-conditioned Helmholtz solver,*** the singularity of horizontal momentum equations at the poles,the polar discretization schemes are described,which include adoption of Arakawa C horizontal grid with ν at poles,incorporation of polar filtering to maintain the computational stability,the correction to Helmholtz equation near the poles,as well as the treatment of semi-Lagrangian interpolation to improve the departure point accuracy,*** balanced flow tests validate the rationality of the treatment of semi-Lagrangian departure point calculation and the polar discretization during long time *** and Suarez tests show that the conservation proper-ties of GRAPES model are quite good.

关键词： nonhydrostatic, global model, semi-implicit, semi-Lagrangian, polar discretization, conservation

GRAPES奇异向量研究及其在暴雨集合预报中的应用

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北京大学学报（自然科学版） 2011年第2期47卷 271-277页

作者：刘永柱杨学胜王洪庆北京大学物理学院大气与海洋科学系北京100871 中国气象科学研究院灾害天气国家重点实验室北京100081

为了产生好的集合预报初始扰动,并能够用有限的集合样本来模拟大气概率密度函数在相空间中的时间演变,把奇异向量法引入非静力GRAPES中尺度模式中,研究了GRAPES奇异向量的基础性问题和基于奇异向量构造集合样本的方法。对2008年7月的一... 详细信息

为了产生好的集合预报初始扰动,并能够用有限的集合样本来模拟大气概率密度函数在相空间中的时间演变,把奇异向量法引入非静力GRAPES中尺度模式中,研究了GRAPES奇异向量的基础性问题和基于奇异向量构造集合样本的方法。对2008年7月的一次西南涡移动带来的暴雨过程进行GRAPES SVs求解,并进行集合预报试验。结果表明:前27个GRAPES SVs反映了分析误差的主要信息;要素的集合平均的均方根误差比控制预报具有更好的预报技巧,且它们的集合离散度随时间逐渐增加,反映了预报误差的主要信息;从降水Brier评分和ROC技巧上可以看出该集合预报具有好的概率预报技巧,能为暴雨预报提供一定的指导作用。

关键词：奇异向量集合预报 GRAPES模式西南涡暴雨