Surface Movement Regularity of Super-Wide Mining Face With Top-Coal Caving

No.4326 super-wide panel of Wangzhuang Coal Mine ( in which the fully-mechanized top-coal caving longwall mining method was used) was monitored for dynamic characteristic of surface movement. The dynamic surface movement in and after mining was predicted by using the Mining Subsidence Prediction System. The results indicate that after mining, the surface above the super-wide panel reaches a state of full subsidence, making the No.309 national highway above the panel be located on the flat bottom of the subsidence basin so that the influence of mining activity in both sides of 4326 panel on the national highway is the smallest.     

基于压差式矢量水听器的目标方位估计

压差式矢量水听器不但能测量声场中质点的声压信息，同时也能测量质点的振速信息．这一特征使其能对声场中的目标进行方位估计。根据复声强定向原理对水下目标进行定位跟踪，试验结果表明，定住误差很小，效果良好。     

Effect of Overcharge on Electrochemical Performance of Sealed-Type Nickel/Metal Hydride Batteries

The effects of overcharge on electrochemical performance of AA size sealed-type nickel/metal hydride（Ni/MH） batteries and its degradation mechanism were investigated. The results indicated that the relationship between the effects of different overcharge currents on the increasing velocity of inner pressure and the degradation velocity of cycle life and discharge voltage remains in almost direct proportion. After overcharge cycles, the positive electrode materials remain the original structure, but there occur some breaks because of the irreversible expand of crystal lattice. And the negative electrode alloy particles have inconspicuous pulverization, but are covered with lots of corrosive products and its main component is rare earth hydroxide or oxide. These are all the main reasons leading to the degradation behavior of the discharge capacity and cycle life of Ni/MH batteries.     

Experimental investigation and numerical simulation on the effect of fissure water pressure in vertical sliding surface

1 Introduction Rock slopes usually contain many structural surfaces in geological engineering. However, the mechanism of rock slope failure has not been profoundly understood. Therefore, it is important to deeply analyze the failure mechanism and stability of such rock slopes through experimental investigation and numerical simulation. Previous site investigations show that water is one of the key factors to induce landslide[1―5]. “No landslide without water” vividly points out the importa…     

Experimental and discrete element numerical analysis of side slope instability induced by fissure water underlying impervious bed

1 Introduction The in situ observations and analysis on the landslide events indicate that water is one of the key factors which induce landslide of the mountain mass[1―8]. The mechanism offissure water inducing landslide can be generalized into three aspects: (1) the softening influence of water weakens the strength of materials on the slip surface[9―11]; (2) the cleft water pressure towards the slide slope free face increases sliding force[12―15]; (3) water pressure on the slip surface lo…     

Experimental study on pore pressure in rock-soil slope during reservoir water level fluctuation

1 Introduction The effect of seepage flow is a key problem in the investigation on the landslide fail- ure. Water in landslide comes mainly from the infiltration of rainwater and seepage flow of ground water. Rivers and reservoirs are the dominant sources of ground water in landslide. The infiltration of water will cause variations of the ground water level in landslides, which sometimes play a key role in the landslide stability. In particular, the fluctuation of water level varies remarkabl…     

KDON-170/350型全低压流程空分设备的操作

简述了KDON 170 /35 0型全低压流程空分设备的操作原理、操作方法和操作依据 ,并探讨了实行间断制氧的可行性     

液化流程中氧液化器的流程组织和相关参数确定

简介了中压循环液化和低压循环液化两种主要的液化流程,对两种流程进行了比较;分析了在中压循环液化流程中单独设置氧液化器的必要性;探讨了在低压氧液化和中压氧液化时不同的氧液化器流程组织形式;提出了低压氧液化时合理的流程组织方案和相关参数。     

论厚板厂精轧工作辊弯辊／平衡系统功能

介绍了宝钢5m宽厚板轧机工作辊的弯辊/平衡系统,对这一系统的功能,机械、液压设备,压力补偿控制原理,闭环控制系统,参考值,板形及平直度控制,错误及警告等内容做了阐述,着重分析了弯辊系统的压力补偿控制原理。     

Fluid-Induced Seismicity: Theory, Modeling, and Applications

Operations including borehole fluid injections are typical for exploration and development of hydrocarbon or geothermic reservoirs. Microseismicity occurring during such operations has a large potential for understanding physics of the seismogenic process as well as in obtaining detailed information about reservoirs at locations as far as several kilometers from boreholes. We propose that the phenomenon of microseismicity triggering by borehole fluid injections is related to the process of the Frenkel–Biot slow wave propagation. In the low-frequency range (hours or days of fluid injection durations) this process reduces to the pore-pressure diffusion. We search for diffusion-related features of induced microseismicity. Two types of such signatures are considered. The first one is related to the geometry of microseismic clouds. Another type of signature is related to the probability of microearthquakes. On this basis we introduce a concept for interpretation of microseismic data which provides a possibility to infer information about hydraulic properties of rocks. Such information can be of significant importance for industrial applications and for understanding physical properties of geological structures.