检索结果-内蒙古大学图书馆

Means of protecting materials from spontaneous coal combustion: Current developments, mechanisms, classifications, and prospects

引用

International Journal of Materials and Structural Integrity 2018年第1-3期12卷 125-150页

作者： Huang, Zhian Xiao, Shanlin Lu, Wei Gao, Yukun Zhang, Yinghua Wang, Hui State Key Laboratory of High-Efficient Mining and Safety of Metal Mines University of Science and Technology Beijing Ministry of Education Beijing10083 China Work Safety Key Lab on Prevention and Control of Gas and Roof Disasters for Southern Coal Mines Hunan University of Science and Technology Xiangtan411201 China School of Civil and Resource Engineering University of Science and Technology Beijing Beijing10083 China College of Mining and Safety Engineering Shandong University of Science and Technology Qingdao266590 China

Spontaneous coal combustion poses serious threats to the world and especially to China, the world's largest coal producer and user. Apart from spurring monetary losses in national exchequers and resource losses for countries, spontaneous coal combustion results in a loss of life, which cannot be measured based on costs. Innumerable researchers and scholars in China and abroad have paid considerable attention to studying means of protecting materials from spontaneous coal combustion. A variety of materials that prevent spontaneous coal combustion have been developed. The goal of this paper is reveal the academic literature on spontaneous coal combustion. In this comprehensive review, mechanisms of spontaneous coal combustion, research findings and advantages and shortcomings of materials that prevent spontaneous coal combustion are explored. In view of different coal mining conditions and material properties, materials that prevent spontaneous coal combustion are classified in accordance with material phases. The development of various coal fire extinguishing materials is discussed. Our comprehensive review can thus be used to prevent and control spontaneous coal combustion and to curtail the currently frequent disasters resulting from spontaneous coal combustion. © 2018 Inderscience Enterprises Ltd.

关键词： Coal combustion

来源：评论

学校读者我要写书评

暂无评论

Study on simulation of non-destructive testing for pipeline defects by ultrasonic guided waves

Study on simulation of non-destructive testing for pipeline ...

引用

2011 Cross Strait Quad-Regional Radio Science and Wireless Technology Conference, CSQRWC 2011

作者： Yang, Hu Wang, Cheng National Key Laboratory for Electronic Measurement Technology North University of China Taiyuan Shanxi 030051 China State Key Laboratory for the Prevention and Control of Explosion Disasters Beijing Institute of Technology Beijing 100081 China

ISBN: (纸本)9781424497904

The detection of defects in pipes is of very importance to the oil, chemistry, gas industry etc. The guided wave method that detects refection waves from defects is developed and proves to be effective. The disadvantages such as low speed and high cost in current non-destructive testing for defects in pipes, the influences of varying exciting frequency on the detection of defects are numerically simulated and analyzed both in straight and curved pipes. And the results suggest that, under the condition of certain wall thickness of pipes, the testing sensitivity increases at first as the exciting frequency increases along, and then it begins to decrease when the frequency arrives at a specific value. It is also concluded that the error in determining the defect locations increases too as the exciting frequency increases. These results have instructive significance on realizing long distance and rapid non-destructive testing for longitudinal ultrasonic guided waves in pipes. At last, the structure of ring transducer that can excite guided waves is also presented in the paper. © 2011 IEEE.

关键词： Guided electromagnetic wave propagation

来源：评论

学校读者我要写书评

暂无评论

Surface and Texture Properties of Tb-Doped Ceria-Zirconia Solid Solution Prepared by Sol-Gel Method

引用

Journal of Rare Earths 2007年第1期25卷 42-47页

作者：樊国栋冯长根张昭 Institute of Chemistry and Chemical Engineering Shaanxi University of Science and TechnologyXianyang 712081 China State Key Laboratory of Prevention and Control of Explosion Disasters Beijing Institute of TechnologyBeijing 100081 China

The three-way catalysts （TWCs） promoters Ce0.6Zr0.4- x TbxO2-y were prepared by sol-gel method. BET surface areas analysis indicated that an increase of the dopant Tb content from x = 0.05 to x = 0.15 favors an increase of surface area from 66.8 to 80.4 m^2· g^-1 compared with the undoped sample Ce0 .6oZr0.40O2 65.1 m^2·g^- 1 after calcination at 650℃. Transmission electron microscopy （TEM） observation indicated that the doped samples have a higher thermal stability. The XRD and Raman spectra confirmed that the Ce0.6Zr0.4-xTbxO2-y cubic solid solution is formed. XPS analysis revealed that Ce and Tb mainly existed in the form of Ce^4＋ and Tb^3 ＋ , and Zr existed in the form of Zr^4＋ on the surface of the samples. The doped samples were homogenous in composition ; the introduction of Tb into the CeO2-ZrO2 promoters resuited in the formation of a solid solution, and the concentration of surface lattice oxygen was increased.

关键词： Ce0.6Zr0.4 - xTbxO2 - y solid solution three-way catalysts sol-gel method surface and texture structure rare earths

来源：评论

学校读者我要写书评

暂无评论

Synthesis of Tb-doped ceria-zirconia solid solution and their characteristics

引用

Gongneng Cailiao/Journal of Functional Materials 2007年第5期38卷 767-770页

作者： Fan, Guo-Dong Feng, Chang-Gen Zhang, Zhao Chen, You-Ning Institute of Chemistry and Chemical Engineering Shanxi University of Science and Technology Xianyang 712081 China State Key Laboratory of Prevention and Control of Explosion Disasters Beijing Institute of Technology Beijing 100081 China

The three-way catalysts (TWCs) promoters Ce0.6Zr0.4-xTbxO2-y, were prepared by sol-gel method. BET surface areas analysis indicate that an increasing of the dopant Tb content from x=0.05 to x=0.15 favors an increasing of surface area from 66.8 to 80.4 m2/g compared to the undoped sample Ce0.60Zr0.40O2 65.1 m2/g after calcination at 650°C. The XRD and Raman spectra confirm that the Ce0.6Zr0.4-xTbxO2-y, cubic solid solution is formed. XPS analysis reveal that valence of Ce and Tb are mainly in form of Ce4+ and Tb3+, and valence of Zr is in form of Zr4+ on the surface of samples. The doped samples are compositionally homogenous, the introduction of Tb to the CeO2-ZrO2 promoters the formation of a solid solution, and increases concentration of surface lattice oxygen.

关键词： Catalysts

来源：评论

学校读者我要写书评

暂无评论

Impact perforation of stiffened steel plates by rigid projectiles

Impact perforation of stiffened steel plates by rigid projec...

引用

作者： Ning, Jianguo Song, Weidong Wang, Cheng Wang, Jing State Key Laboratory of Prevention and Control of Explosion Disasters Beijing Institute of Technology Beijng 100081 China

An experimental program has been conducted to study the perforation of stiffened steel plates by truncated oval-nose projectiles at normal impacts. The projectiles of 104mm diameter were fired at 921A stiffened plates with thickness *** for the base plate at an initial velocity from 560m/s to 620m/s. High speed camera system was employed to record the perforation process and from the digital images, impact angles and projectile velocities during perforation were determined using image processing. Numerical simulations have been performed for projectiles against single and layered plates adopted in the experiments. The perforation process is explored in details and the deformation modes are obtained. By adopting an energy method, a four-stage analytical model that accurately predicts the residual velocity is developed. Simulation results, experimental data and theoretical predictions are reasonably well correlated.

关键词： Steel structures

来源：评论

学校读者我要写书评

暂无评论

A viscoelastic continuum damage model for reinforced concrete subjected to shock loading

A viscoelastic continuum damage model for reinforced concret...

引用

作者： Ning, Jianguo Shang, Lin Sun, Yuanxiang State Key Laboratory of Prevention and Control of Explosion Disasters Beijing Institute of Technology Beijing 100081 China

In this paper, we analyze a RVE of concrete reinforced (RC) with steel reinforcing bar in two vertical directions on basis of the thoughts of composite material and propose that in the ideal case the constitutive equation of reinforce concrete is declared to multiply the viscoelastic constitutive equation of concrete by a reinforcing multiplier G, which is depended on material characters and arrange mode of steel reinforcing bar. In the model, we draw the growing damage law on the assumption that damage only occur in the concrete. Subsequently, we obtain the damage viscoelastic constitutive equation of reinforced concrete. Lastly, the comparison with the plate impact test results of specimens shows that the proposed model can give consistent prediction of the dynamic behavior of SFRC.

关键词： Viscoelasticity

来源：评论

学校读者我要写书评

暂无评论

An experimental study on creep deformation of PBX with laser moiré interferometry method

An experimental study on creep deformation of PBX with laser...

引用

作者： Xie, Huimin Shi, Hang Chen, Pengwan Huang, Fenglei Fang, Daining Dept. of Eng. Mechanics Tsinghua University Beijing 100084 China State Key Lab of Prevention and Control of Explosion Disasters Beijing Institute of Technology Beijing 100081 China

In this paper, the creep deformation of PBX was measured using the moiré interferometry. The experimental results show a different creep process compared with pure high polymer and this phenomenon is preliminary ... 详细信息

关键词： Creep

来源：评论

学校读者我要写书评

暂无评论

Critical load between sea ice and sea structure

Critical load between sea ice and sea structure

引用

作者： Fan, Wenxin Song, Weidong Ning, Jianguo Graduate School North University of China Taiyuan 030051 China State Key Laboratory of Prevention and Control of Explosion Disasters Beijing Institute of Technology Beijng 100081 China

The main objective of this paper is to propose the buckling equations of the sea sheets under concentrated forces. Two different cases of the acting forces are considered in this paper and the buckling equations of them are deprived, respectively. Then, the dimensionless forms of these equations are given. Furthermore, by adopting a numerical method, two cases of different thickness of the ice sheet and different distances between sea structures are explored. On the basis of the buckling equations, the expressions of the critical load between sea ice and sea structures are obtained. Finally, the relationship between the critical load factor and the dimensionless radius are presented.

关键词： Structural loads

来源：评论

学校读者我要写书评

暂无评论

An analysis on dynamic damage on concrete obstruct subjected to underwater explosion shock waves

An analysis on dynamic damage on concrete obstruct subjected...

引用

作者： Hao, Li Ning, Jian-Guo Beijing Institute of Civil Engineering and Architecture Beijing 100044 China State Key Lab for the Prevention and Control of Explosion Disaster Beijing Institute of Technology Beijing 100081 China

Based on the multi-material Eulerian algorithm, the damage effects of concrete obstruct subjected to underwater explosion shock waves are simulated by using the NM-MMIC code which is a 2D multi-material elastic-plastic hydrodynamics code with C++ language. According to the simulation results of underwater explosion, the optimum charge, the damage degree and the damage laws of obstruct are obtained. The simulation results show a good agreement with that obtained by DYNA2D. Thus the given study indicates that the model and algorithm presented in this paper are reasonable and the simulation method can be used for designing and estimating ammunitions against obstructs in water.

关键词： Concrete construction

来源：评论

学校读者我要写书评

暂无评论

Recent Developments in Doping and Structural Modification of Ceria-Based Catalysts

引用

Journal of Rare Earths 2005年第3期23卷 309-313页

作者：冯长根樊国栋 State Key Laboratory of Prevention and Control of Explosion Disasters Beijing Institute of Technology Beijing 100081 China

Recent development in the modification of ceria-based catalysts for exhaust gas treatment was reviewed with the dependence of redox properties on structural characters of materials. The doping of ceria with different cations such as rare earth or transition metal oxides results in improvement of structural stability, catalytic function and resistance to sintering at high temperatures. Aging and reduction treatment at high temperatures promote ceria reduction and is beneficial for oxygen storage capacity of the three-way catalysts. Chemical filing technique is very effective in modifying the redox property in the low temperature regions.

关键词： ceria-based oxides dopants structural modification redox aging chemical filing rare earths

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：