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Journal of Materials Science and Chemical Engineering 2015年第7期3卷 75-80页

作者： N. A. Bokov Institute of Silicate Chemistry Russian Academy of Sciences St. Petersburg Russia

The data describing of the light scattering intensity relaxation above the glass transition temperature by boron oxide obtained by using of the temperature jump methods are presented. It is found that the stabilization of the glass at 220℃ resulted in increasing of the anisotropic intensity at the same time the isotropic intensity is not practically unchangeable. It is shown that after the temperature jump to 330℃the intensity is characterized by the formation of a maximum. This effect is in compliance with the results obtained for the other oxide glasses. It is established that characteristic time of the relaxation of the maximum height is about two orders of magnitude more than the structural relaxation time for this temperature.

关键词： static Light Scattering Glass Transition Relaxation Time Boron Oxide

Study on Approach of static Security Assessment Accounting for Electro-thermal Coupling

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Energy and Power Engineering 2013年第4期5卷 703-707页

作者： Mengxia Wang Hongbin Sun Jinxin Huang Qiang Zhang Dept. of Electrical Engineering Tsinghua University Beijing China Shandong Electric Power Dispatching and Control Center Jinan China State Grid of China Technology College Jinan China

A static security assessment approach considering electro-thermal coupling of transmission lines is proposed in this paper. Combined with the dynamic thermal rating technology and energy forecasting, the approach can track both the electrical variables and transmission lines’ temperature varying trajectory under anticipated contingencies. Accordingly, it identifies the serious contingencies by transmission lines’ temperature violation rather than its power flow, in this case the time margin of temperature rising under each serious contingency can be provided to operators as warning information and some unnecessary security control can also be avoided. Finally, numerical simulations are carried out to testify the validity of the proposed approach.

关键词： Power System Dynamic Thermal Rating static Security Assessment Transmission Line Electro-thermal Coupling

EXPERIMENTAL AND THEORETICAL STUDY OF static-DYNAMIC MIXED MODE BRITTLE FRACTURE OF ROCK

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Journal of Central South University 1998年第2期10卷 47-50页

作者： Li Zhenzi Lin Guoxiang Xu Jicheng Zhang Jingyi Luo Zhang (Department of Architecture Engineering, Central South University of Technology,Changsha 410083,China) Zhou Hongbin Li Huijian (Department of Civil Engineering,Yan shan University,H

Ｖａｒｉｏｕｓｍｏｄｅ－Ⅰｉｎｖｅｓｔｉｇａｔｉｏｎｓｉｎｔｈｅｔｈｅｏｒｙｏｆｌｉｎｅａｒｅｌａｓｔｉｃｆｒａｃｔｕｒｅｍｅｃｈａｎｉｃｓａｒｅｉｍｐｏｒｔａｎｔｉｎｄｅｔｅｒｍｉｎｉｎｇｔｈｅｆｒａｃｔｕｒｅｃｏ... 详细信息

Ｖａｒｉｏｕｓｍｏｄｅ－Ⅰｉｎｖｅｓｔｉｇａｔｉｏｎｓｉｎｔｈｅｔｈｅｏｒｙｏｆｌｉｎｅａｒｅｌａｓｔｉｃｆｒａｃｔｕｒｅｍｅｃｈａｎｉｃｓａｒｅｉｍｐｏｒｔａｎｔｉｎｄｅｔｅｒｍｉｎｉｎｇｔｈｅｆｒａｃｔｕｒｅｃｏｎｓｔａｎｔｓ．Ｔｏａｎａｌｙｓｅ...

关键词： static dynamic mixed mode fracture rock

Some Equivalences and Dualities via static Modules

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Advances in Pure Mathematics 2011年第6期1卷 359-362页

作者： Salah Al-Nofayee Syed Khalid Nauman 不详

For a ring A, an extension ring B, a fixed right A-module M, the endomorphism ring D formed by M, the endomorphism ring E formed by , and the endomorphism ring F formed by HomA (B,M), we present equivalences and dualities between subcategories of B-modules which are finitely cogenerated injective as A-modules and E-modules and F-modules which are finitely generated projective as D-modules.

关键词： static Modules Finitely Cogenerated Injective Modules Finitely Generated Projective Modules

Characteristics and Construction Technology Analysis of static Pressure Prestressed Pipe Piles in Construction Engineering

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Journal of Architectural Research and Development 2018年第3期2卷 55-58页

作者： Wu Cuipeng Infrastructure Office Xi'an International Studies UniversityXi'anShaanxiChina

The development of urbanization has led to an increase in the number and scale of construction projects and the types of building construction engineering are getting advance and diverse due to the rapid development of technology.One of them is the static pressure prestressed pipe pile which is the most commonly used technology in modern building construction work.It is mainly used for pile foundation in construction work,and it has the advantages in less pollution,low noise,and high efficiency compared to the traditional pile foundation.Study on the characteristics of static pressure prestressed pipe pile must be carried out and strengthened the research to increase the effectiveness and quality of static pressure prestressed pipe pile on construction works.This paper is mainly to analyzed the characteristic and construction technology of static pressure prestressed pipe piles on building construction work.

关键词： building construction work static pressure prestressed pipe pile characteristic construction work technology

Efficacy of static magnetic field for pain of adjuvant arthritis rats

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Advances in Bioscience and Biotechnology 2012年第4期3卷 511-515页

作者： Shigeyuki Kanai Norimasa Taniguchi Department of Physical Therapy Faculty of Health Science Kansai University of Health Science Osaka Japan Research Section for Magnetics Product Development Department Development Division PIP Co Ltd Osaka Japan

Rats suffering from adjuvant arthritis (AA) were used to examine the effect of a static magnetic field (SMF) upon pain relief. Rats were divided into SMF- treated AA rats, non-SMF treated AA rats and control rats. Following SMF stimulation, we measured blood flow volume in the paw and then reactive speed response to thermal stimulation. The AA groups exhibited significantly lower blood volume and reactivity to thermal stimulation compared to the control group. Compared to non-SMF, SMF exhibited increased blood flow volume in both the tail and paw, along with an increased reactive speed response to thermal stimulation. Our findings suggest that an improved of blood flow and reactive speed response, induced by SMF, appears to be effective for the relief of pain induced by chronic inflammation.

关键词： static Magnetic Field (Smf) Adjuvant Arthritis (Aa) Blood Flow Reactive Speed Response

Comparison between static and dynamic warm-up exercise regimes on lower limb muscle power

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Health 2009年第2期1卷 117-120页

作者： Jose Shelton G. V. Praveen Kumar 不详

Aim: The purpose of this study was to compare static and dynamic warm-up regimes on lower limb muscle power and thereby the perform-ance of the individual. Methodology: Twenty eight (28) subjects were assigned into groups consisting of 2 members. From each group, 1 subject performed the static stretching and the other subject performed dynamic stretching as warm-up. This was followed by non-counter movement jumps on a force platform and the vertical jump heights were recorded. Data were analysed using one-way ANOVA and paired t-test at 0.05 alpha. Result: The results showed that dynamic stretching as warm-up causes significant increase (p=0.01) in the vertical jump height as compared to static stretching (p=0.03). Discussion: The increase in vertical jump height could be related to the increase in force pro-duction which plays an important role during the vertical jump test. On the other hand the decrease in vertical jump height following static stretching could be attributed to a decrease in the force production in the muscles. Conclusion: Dynamic warm-up increases the vertical lump height, whereas static stretching decreases the jump height of the athlete.

关键词： static Stretching Dynamic Stretching Force Production Post Activation Potentiation

Mechanism of rock burst caused by fracture of key strata during irregular working face mining and its prevention methods

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International Journal of Mining Science and Technology 2019年第6期29卷 889-897页

作者： Zengqiang Yang Chang Liu Hengzhong Zhu Fuxing Xie Linming Dou Jianhang Chen School of Resource and Safety Engineering China University of Mining&TechnologyBeijing 100083China State Key Laboratory of Coal Resources and Mine Safety China University of Mining&TechnologyXuzhou 221116China Science&Technology Innovation Center Coal Mining and Designing DepartmentTiandi Science&Technology Co.LtdBeijing 100013China Mine Construction Branch of Research Institute China Coal Research InstituteBeijing 100013China

To study the occurrence mechanism of rock burst during mining the irregular working face,the study took irregular panel 7447 near fault tectonic as an engineering background.The spatial fracture characteristic of overlying strata was analyzed by Winkler elastic foundation beam theory.Furthermore,the influence law of panel width to suspended width and limit breaking span of key strata were also analyzed by thin plate theory.Through micro-seismic monitoring,theoretical analysis,numerical simulation and working resistance of support of field measurement,this study investigated the fracture characteristic of overlying strata and mechanism of rock burst in irregular working face.The results show that the fracture characteristic of overlying strata shows a spatial trapezoid structure,with the main roof being as an undersurface.The fracture form changes from vertical‘‘O-X"type to transverse‘‘O-X"type with the increase of trapezoidal height.From the narrow mining face to the wide mining face,the suspended width of key strata is greater than its limit breaking width,and a strong dynamic load is produced by the fracture of key strata.The numerical simulation and micro-seismic monitoring results show that the initial fracture position of key strata is close to tailgate 7447.Also there is a high static load caused by fault tectonic.The dynamic and static combined load induce rock burst.Accordingly,a cooperative control technology was proposed,which can weaken dynamic load by hard roof directional hydraulic fracture and enhance surrounding rock by supporting system.

关键词： Rock burst Irregular working face Key strata Dynamic and static combined load Cooperative control

Dynamic failure risk of coal pillar formed by irregular shape longwall face:A case study

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International Journal of Mining Science and Technology 2018年第5期28卷 775-781页

作者： Yixin Zhao Hao Wang Shimin Liu Zonglong Mu Zhiguo Lu Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources School of Resources and Safety Engineering China University of Mining & Technology Department of Energy and Mineral Engineering G3 Center and EMS Energy Institute Pennsylvania State University University Park School of Mines China University of Mining & Technology

Irregular shape workface would result in the presence of coal pillar, which leads to high stress concentration and possibly induces coal bumps. In order to study the coal bump mechanism of pillars, static and dynamic stress overlapping(SDSO) method was proposed to explain the impacts of static stress concentration and tremors induced by mining activities. The stress and deformation in surrounding rock of mining face were analyzed based on the field case study at 1303 workface in Zhaolou Coal Mine in China.The results illustrate that the surrounding rock of a workface could be divided into four different zones,i.e., residual stress zone, stress decrease zone, stress increase zone and original stress zone. The stress increase zone is prone to failure under the SDSO impact loading conditions and will provide elastic energy for inducing coal bump. Based on the numerical modelling results, the evolution of static stress in coal pillar as the size of gob increasing was studied, and the impact of dynamic stress was investigated through analyzing the characteristics of tremor activities. The numerical results demonstrate the peak value of vertical stress in coal pillar rises from about 30 MPa with mining distance 10 m to 52.6 MPa with mining distance 120 m, and the location of peak stress transfers to the inner zone of coal pillars as the workface moves forward. For the daily tremor activities, tremors with high energy released indicate high dynamic stress disturbance on the surrounding rock, therefore, the impact of dynamic stressing is more serious during workface extension period because the tremor frequency and average energy after workface extension are higher than those before the workface extension.

关键词： Coal bump Coal pillar Tremor Irregular shape longwall face static and dynamic stress overlapping

Rock burst mechanism analysis in an advanced segment of gob-side entry under different dip angles of the seam and prevention technology

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International Journal of Mining Science and Technology 2018年第6期28卷 891-899页

作者： Yang Zengqiang Liu Chang Tang Shichuan Dou Linming Cao Jinglong School of Resource and Safety Engineering China University of Mining and Technology State Key Laboratory of Coal Resources and Mine Safety China University of Mining and Technology Beijing Key Laboratory of Occupational Health and Safety Beijing Municipal Institute of Labor Protections

In order to investigate the frequent occurrences of rock burst in gob-side entry during the mining process of the mining zone No. 7, the mechanical model of main roof of fully-mechanized caving mining before breaking was established by the Winkler foundation beam theory, and the stress evolution law of surrounding rock with different dip angles of the seam during the mining process was analyzed by using FLAC3 D. The results show that: with the dip angle changing from 45° to 0°, the solid-coal side of gobside entry begins to form an L-shaped stress concentration zone at a dip angle of 30°, and the stress concentration degree goes to higher and higher levels. However, the stress concentration degree of the coalpillar side goes to lower and lower levels; the influence range and peak stress of the abutment at the lateral strata of adjacent gob increase with dip angle decreasing and reach a maximum value at a dip angle of 0°, but the tailgate is not affected; the abutment pressure superposition of two adjacent gobs leads to stress concentration further enhancing in both sides of gob-side entry. With the influence of strong mining disturbance, rock burst is easily induced by dynamic and static combined load in the advanced segment of gob-side entry. To achieve stability control similar to that in the roadway, the key control strategy is to reinforce surrounding rock and unload both sides. Accordingly, the large-diameter drilling and high-pressure water injection combined unloading and reinforced support cooperative control technology was proposed and applied in field test. The results of Electromagnetic Emission(EME) and field observation showed that unloading and surrounding rock control effect was obvious.

关键词： Rock burst Change of dip angle Gob-side entry Dynamic and static combined load Cooperative control Electromagnetic emission