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露天煤矿智能化建设现状及方案

露天采矿技术 2024年第2期39卷 34-37页

作者：张震男武牡丹智能采矿装备技术全国重点实验室山西太原030032 山西太重智能采矿装备技术有限公司山西太原030032

分析了露天煤矿智能化建设现状,介绍当前国家政策对煤矿智能化建设的支持与露天煤矿智能化验收情况。以建设露天煤矿高级智能化建设水平为总体目标,提出自底而上有序推进、工艺系统智能化为核心的建设原则,介绍了“1+4”智能化露天煤矿... 详细信息

分析了露天煤矿智能化建设现状,介绍当前国家政策对煤矿智能化建设的支持与露天煤矿智能化验收情况。以建设露天煤矿高级智能化建设水平为总体目标,提出自底而上有序推进、工艺系统智能化为核心的建设原则,介绍了“1+4”智能化露天煤矿平台架构,明确了露天矿智能化建设内容。

关键词：露天煤矿智能化建设工艺系统智能化总体架构智能开采

Modeling rock fragmentation by coupling Voronoi diagram and discretized virtual internal bond

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Theoretical & Applied Mechanics Letters 2020年第5期10卷 321-326页

作者： Sai Liu zhennan zhang School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The rock fragmentation involves the inter-block and the intra-block fracture.A simulation method for rock fragmentation is developed by coupling Voronoi diagram(VD)and discretized virtual internal bond(DVIB).The DVIB is a lattice model that consists of *** VD is used to generate the potential block structure in the DVIB *** potential block may contain any number of bond *** characterize the inter-block fracture,a hyperelastic bond potential is employed for the bond cells that are cut by the VD *** to characterize the intra-block fracture,an elastobrittle bond potential is adopted for the bonds in a *** this method,both the inter-block and intra-block fracture can be well *** simulation results suggest that this method is a simple and efficient approach to rock fragmentation simulation with block smash.

关键词： Rock fragmentation Block smash Voronoi diagram Discretized virtual internal bond Fracture

A MULTISCALE MECHANICAL MODEL FOR MATERIALS BASED ON VIRTUAL INTERNAL BOND THEORY

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Acta Mechanica Solida Sinica 2006年第3期19卷 196-202页

作者： zhang zhennan Ge Xiurun Li Yonghe Department of Civil Engineering Shanghai University Shanghai 200072 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Institute of Geotechnical Engineering Shanghai Jiaotong University Shanghai 200030 China Institute of Rock and Soil Mechanics the Chinese Academy of Sciences Wuhan 430071 China

Only two macroscopic parameters are needed to describe the mechanical properties of linear elastic solids, i.e. the Poisson＇s ratio and Young＇s modulus. Correspondingly, there should be two microscopic parameters to determine the mechanical properties of material if the macroscopic mechanical properties of linear elastic solids are derived from the microscopic level. Enlightened by this idea, a multiscale mechanical model for material, the virtual multi-dimensional internal bonds （VMIB） model, is proposed by incorporating a shear bond into the virtual internal bond （VIB） model. By this modification, the VMIB model associates the macro mechanical properties of material with the microscopic mechanical properties of discrete structure and the corresponding relationship between micro and macro parameters is derived. The tensor quality of the energy density function, which contains coordinate vector, is mathematically proved. From the point of view of VMIB, the macroscopic nonlinear behaviors of material could be attributed to the evolution of virtual bond distribution density induced by the imposed deformation. With this theoretical hypothesis, as an application example, a uniaxial compressive failure of brittle material is simulated. Good agreement between the experimental results and the simulated ones is found.

关键词： virtual multi-dimensional internal bond material property dimensionality multiscale modeling molecular dynamics virtual internal bond

Arsenic redox transformation by Pseudomonas ***-2 isolated from arsenic-contaminated soil in Hunan,China

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Journal of Environmental Sciences 2016年第9期28卷 165-173页

作者： zhennan zhang Naiyi Yin Xiaolin Cai Zhenzhou Wang Yanshan Cui College of Resources and Environment University of Chinese Academy of Sciences Beijing 101408 China Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A mesophilic,Gram-negative,arsenite[As（Ⅲ）]-oxidizing and arsenate[As（V）]-reducing bacterial strain,Pseudomonas ***-2,was isolated from an As-contaminated *** analysis based on 16 S r RNA gene sequencing indicated that the strain was closely related to Pseudomonas *** aerobic conditions,this strain oxidized 92.0%（61.4 μmol/L） of arsenite to arsenate within 3 hr of *** of As（V） to As（Ⅲ） occurred in anoxic *** ***-2 is among the first soil bacteria shown to be capable of both aerobic As（Ⅲ） oxidation and anoxic As（V） *** strain,as an efficient As（Ⅲ） oxidizer and As（V） reducer in Pseudomonas,has the potential to impact arsenic mobility in both anoxic and aerobic environments,and has potential application in As remediation processes.

关键词： Arsenic Arsenite oxidation Arsenate reduction Detoxification Pseudomonas

Bedding plane-embedded augmented virtual internal bonds for fracture propagation simulation in shale

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Theoretical & Applied Mechanics Letters 2021年第3期11卷 180-185页

作者： Zihan Liu zhennan zhang Ahmad Ghassemi Department of Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China Mewbourne School of Petroleum and Geological Engineering The University of OklahomaNormanOK 73091USA

To effectively simulate the fracture propagation in shale,the bedding plane(BP)effect is incorporated into the augmented virtual internal bond(AVIB)constitutive relation through BP *** the BP-embedded AVIB with the theory of transverse isotropy,it is found the approach can represent the anisotropic properties induced by parallel *** the simulation example,it is found that this method can simulate the stiffness anisotropy of shale and can represent the effect of BPs on hydraulic fracture propagation *** with the BP-embedded virtual internal bond(VIB),this method can account for the various Poisson’s *** provides a feasible approach to simulate the fracture propagation in shale.

关键词： Shale Bedding plane Constitutive model Hydraulic fracture Augmented virtual internal bond

超深碳酸盐岩储层岩石三轴压缩实验与数值模拟研究

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断块油气田 2024年第1期31卷 134-139页

作者：黄腾达纪成赵兵朱其志李加虎张振南上海交通大学船舶海洋与建筑工程学院上海200240 中国石化缝洞型油藏提高采收率重点实验室新疆乌鲁木齐830011 河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210098

为了研究超深碳酸盐岩储层的岩石力学特性,文中以取自埋深约8350 m的顺北油气田奥陶系储层碳酸盐岩真实岩样为研究对象,按热处理与无热处理,在110 MPa围压范围内进行三轴压缩实验,从而得到高围压下的岩石力学特性。实验结果表明:高围压... 详细信息

为了研究超深碳酸盐岩储层的岩石力学特性,文中以取自埋深约8350 m的顺北油气田奥陶系储层碳酸盐岩真实岩样为研究对象,按热处理与无热处理,在110 MPa围压范围内进行三轴压缩实验,从而得到高围压下的岩石力学特性。实验结果表明:高围压下,岩石表现强烈的塑性流动,加热处理会使得岩石强度降低,但随着围压等级的升高,不同温度下的岩石峰值应力又趋于一致。基于Drucker-Prager屈服准则,发展了塑性硬化参数与等效塑性应变之间的关系,对2种温度下的岩石三轴压缩实验进行数值模拟,结果很好地再现了三轴压缩应力-应变曲线。作为拓展应用,采用所建立的弹塑性本构对单条裂缝压裂过程进行模拟,发现在本岩样所在的储层条件下,压裂过程中的裂缝扩展不受岩石塑性的影响,这一点与裂缝闭合过程完全不同,这为目标储层压裂改造提供了有意义的借鉴。

关键词：超深储层碳酸盐岩高围压三轴压缩实验数值模拟

Modeling shale with consideration of bedding planes by cohesive finite element method

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Theoretical & Applied Mechanics Letters 2019年第6期9卷 397-402页

作者： Chunfang Li zhennan zhang School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University

Shale contains distributed directional bedding planes,which make the shale transverse *** model shale with consideration of the bedding planes,a cohesive finite element method(CFEM)is developed based on the randomized triangular *** interface orientation generated from such mesh tends to be uniformly distributed with the element number *** represent the bedding plane,the interfaces aligned with the bedding plane are assigned the cohesive law that characterizes the bedding plane while the other interfaces are assigned the cohesive law that characterizes the *** this means,the anisotropy characteristics of the stiffness and the strength of shale are well *** simulation examples demonstrate that the bedding plane has a significant influence on the fracture trajectory,which is consistent with the observation in the *** is suggested that this modeling method of shale is *** provides an alternative approach to fracture simulation in shale.

关键词： Shale Bedding plane Cohesive finite element Transverse isotropy Fracture simulation

Triangular element partition method with consideration of crack tip

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Science China(Technological Sciences) 2013年第10期56卷 2081-2088页

作者： zhang zhennan ZHENG Hong GE XiuRun School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong University Institute of Rock and Soil Mechanics Chinese Academy of Sciences

In fracture simulation,how to model the pre-existing cracks and simulate their propagation without remeshing is an important *** newly developed triangular element partition method(TEPM)provides an efficient approach to this *** firstly meshes the cracked body regardless of the geometry integrity of the interesting object with triangular *** the meshing procedure is completed,some elements are intersected by *** the element intersected by a crack,the TEPM takes the element partition technique to incorporate the discontinuity into the numerical model without any interpolation *** this approach,the TEPM can simulate fracture without mesh *** the TEPM,all the cracked elements are treated as the usual partitioned elements in which the crack runs *** virtual node pairs(the intersection points of crack faces and elements)at the opposite faces of the crack move *** displacements are respectively determined by their neighbor real nodes(nodes formatted in the original mesh scheme)at the same side of the ***,among these cracked elements,the element containing a crack tip,referred to as the crack tip element thereafter,behaves differently from those cut through by the *** influence on the singular field at the vicinity of the fracture tip becomes increasingly significant with the element size *** the crack tip element,the virtual node pair at the crack tip move consistently before fracture occurs while the virtual node pair separate and each virtual node moves independently after the fracture ***,the crack tip element is automatically transformed into the usual partitioned *** the present paper,the crack tip element is introduced into the TEPM to account for the effect of the crack *** examples indicate that the present method is almost free from the element size *** can reach the same precision as the conventional finite element met

关键词： triangular element partition method crack tip element fracture simulation multi-cracked body

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冬虫夏草抗低氧疲劳作用研究

青海科技 2024年第1期31卷 108-115页

作者：赵苗张振楠关舒函张明魏立新毕宏涛青海大学医学院药学系西宁810001 中国科学院西北高原生物研究所青海省藏药药理学和安全性评价研究重点实验室西宁810008 烟台大学生命科学学院烟台264005 中国科学院藏药研究重点实验室西宁810008

急性高原低氧环境暴露会损害机体的供氧能力和运动耐力,产生疲劳状态。随着高原旅游和高原作业人群的日益增多,如何提高高原人群的运动机能、缓解疲劳状态成为高原医学需迫切解决的问题之一。本研究模拟6000 m海拔氧浓度(空气氧含量11.3... 详细信息

急性高原低氧环境暴露会损害机体的供氧能力和运动耐力,产生疲劳状态。随着高原旅游和高原作业人群的日益增多,如何提高高原人群的运动机能、缓解疲劳状态成为高原医学需迫切解决的问题之一。本研究模拟6000 m海拔氧浓度(空气氧含量11.35%)环境下给予冬虫夏草(300~900 mg/kg/d剂量,连续7天),以探究冬虫夏草对低氧环境下小鼠运动性疲劳的保护作用。研究结果表明,与模型组低氧疲劳小鼠相比,冬虫夏草组小鼠负重游泳力竭时间显著增加,血清尿素氮(BUN)、乳酸脱氢酶(LDH)、肌酸激酶(CK)、肌酐(CRE)和丙二醛(MDA)含量显著减少,血清总抗氧化能力(T-AOC)、肌糖原和肝糖原含量显著增加,肝脏组织和肌肉组织病理学变化得到明显改善。由此可见,冬虫夏草具有良好的抗低氧疲劳作用,其活性主要是通过提高肌肉强度、增强抗氧化能力、降低机体运动强度、调节能量代谢等途径来实现,特别是冬虫夏草中剂量(600 mg/kg/d)组效果最稳定。

关键词：冬虫夏草高原环境低氧疲劳运动机能抗疲劳作用