岩体质量分级的改进模糊综合评价法

模糊综合评价法是评价岩体质量等级的一种有效方法。传统的模糊综合评价法中权重赋值比较片面,并且多采用最大隶属度原则做决策,可能造成数据信息丢失与说服力不足的问题,为此,提出通过熵权法确定权重系数,并通过计算有效度来修正传统方法中的最大隶属度原则,建立了改进的模糊综合评价模型。选取单轴饱和抗压强度 、完整性系数 、岩石基本质量指标RQD、结构面影响系数、地下水影响系数作为评价指标,用改进的模糊综合评价模型对沂南金矿金场矿区右2巷道的围岩质量进行了分级,结果表明,围岩质量整体较差,处于Ⅳ~Ⅴ级范围内。将分级结果与传统模糊综合评价法和BQ分类法的评价结果进行了对比,发现改进后的模糊综合评价结果与BQ法更为接近,同时克服了传统模糊综合评价法和BQ法的不足,得到了更加科学合理的分级结果。根据上述分级结果,提出了首先进行喷浆护壁,然后铺设金属网+系统锚杆的支护措施,以保证围岩完整性及稳定性。     

Investigation of aluminum gate CMP in a novel alkaline solution

Beyond 45 nm, due to the superior CMP performance requirements with the metal gate of aluminum in the advanced CMOS process, a novel alkaline slurry for an aluminum gate CMP with poly-amine alkali slurry is investigated. The aluminum gate CMP under alkaline conditions has two steps:stock polishing and fine polishing. A controllable removal rate, the uniformity of aluminum gate and low corrosion are the key challenges for the alkaline polishing slurry of the aluminum gate CMP. This work utilizes the complexation-soluble function of FA/O Ⅱ and the preference adsorption mechanism of FA/O Ⅰ nonionic surfactant to improve the uniformity of the surface chemistry function with the electrochemical corrosion research, such as OCP-TIME curves, Tafel curves and AC impedance. The result is that the stock polishing slurry (with SiO₂ abrasive) contains 1 wt.% H₂O₂ ,0.5 wt.% FA/O Ⅱ and 1.0 wt.% FA/O Ⅰ nonionic surfactant. For a fine polishing process, 1.5 wt.% H₂O₂ , 0.4 wt.% FA/O Ⅱ and 2.0 wt.% FA/O Ⅰ nonionic surfactant are added. The polishing experiments show that the removal rates are 3000±50 Å/min and 1600±60 Å/min, respectively. The surface roughnesses are 2.05±0.128 nm and 1.59±0.081 nm, respectively. A combination of the functions of FA/O Ⅱ and FA/O Ⅰ nonionic surfactant obtains a controllable removal rate and a better surface roughness in alkaline solution.     

Numerical Simulation of Mine Water Inflow with an Embedded Discrete Fracture Model: Application to the 16112 Working Face in the Binhu Coal Mine,China

Properly accounting for the effect of heterogeneity of aquifers and accurately predicting mine water inflow during the mining process is still a challenging problem in China. We developed a stochastic modelling methodology that considers a large range of possible multi-scale fracture configurations and heterogeneous porous rock to predict mine water inflow close to the observed data. The coupled discrete fracture–rock matrix models were built for the Binhu coal mine 16,112 working face with the Monte Carlo method. The models were solved using the embedded discrete fracture model to calculate groundwater inflow from the aquifer beneath the coal seam floor. The calculated results and the observed groundwater inflows in the field agreed well. Sensitivity analysis indicates that groundwater inflow increases with increased fracture length and fracture density. The effect of natural fractures introduces a large uncertainty for the models, due to the existence of long fractures that could act as conduits between the Ordovician limestone and no. 14 aquifers. The results highlight the importance of multi-scale fractures on modeling and simulating flow in the mine area.

     

浓硝酸工段设备设计中的几点看法

围绕浓硝酸工段设备设计及使用中经常遇到的跑、冒、滴、漏现象，从设计的角度来论述关于垫片的选用，液面计的选择，法兰密封面的选择等方面的几点看法。