鱼田堡煤矿地应力的超声波检测

利用声波在弹性介质中的传播特性,阐述了在鱼田堡煤矿进行的地应力超声波检测,并通过多元非线性模拟方法和二次正交变换,得到了被测点的声波椭球,然后在实验室进行了不等压三轴条件下应力与声波关系的实验研究,得出了被测点的应力椭球,从而确定出了测点部位处三个主应力方向和量级,为地应力场的数值分析提供了一定的依据。     

潘庄井田煤储层渗透率预测

为提高煤层开采水平,通过分析地应力、埋深、煤储层压力等对渗透率的影响,分别构建煤储层渗透率与其影响因素之间的拟合关系,利用定量关系对潘庄井田煤储层的渗透率进行了系统预测.预测结果显示:潘庄井田上主煤层3煤的渗透率大约在0.3×10-3～2.1×10-3μm2,下主煤层15煤的渗透率大约在0.4×10-3～0.8×10-3μm2.     

Evaluation of crustal stability in the lower Yellow River region

The evaluation of crustal stability in the lower Yellow River region （LYR） is vital to the engineering project of the Yellow River embankment and construction of the Huang-Huai-Hai plain. From three aspects of tectonic stability, surface stability and medium stability, this paper analyzes in detail the factors such as tectonic activity, tectonic stress, exogenic geologic disasters and ground material composition which affect crustal stability in the study area and the spatial distributions of subordinate degree of the evaluation factors. It then constructs the crustal stability evaluation model of fuzzy mathematics based on GIS by using AHP to among the various factors find out the interrelations comprehensive evaluation of fuzzy mathematics and the functions of spatial overlay and spatial database of ArcGIS. Based upon this the crustal stability evaluation is carried out, the results show that the areas of stable and instable regions are basically the same, being 48.72% and 51.28% respectively. The area of moderate stable region takes a dominant position, being about 70.58%. The crust instable region presents zonal distribution and under the control of tectonic faulted belt. But the region where the LYR runs across is mostly instable with a total length of the river being 568.345 km, or 78.93% of all. The river reach where the crustal stability is relatively poor along the LYR is concentrated in the Lankao-Dongping section.     

Crustal activities recorded in coral reefs in the northwestern South China Sea

Coral reefs in the northwest of South China Sea have recorded the information from not only the environmental variation but also the crustal activities there during their development. The main crustal activities correlated with the coral reef development include fault, seismic, and volcano activities, etc. The high-resolution spark seismic profiles in the northwestern South China Sea show that the fault activities in the coral reef region have been clearly recorded, and appear as neonatal faults incising reefs. Earthquakes in the coral reef region are rather intense, especially the two occurring on December, 31, 1994, and January, 10, 1995, around the southwest of Leizhou Peninsula, with the magnitude of 6.1 and 6.2, respectively. They have great influence on the growth of the local coral reefs. Quaternary volcanos are active in the northwestern South China Sea, especially around the southwest of Leizhou Peninsula, and they have obvious control of the coral reef development. Some submarine volcanoes form the substrates of coral reef, while a few emerge above the sea surface and form coral islands.     

GH36A合金电渣重熔Mg含量的控制

本文根据文献热力学数据,导出了反应; [Mg]％_(F~0)+[O]％=MgO_((s))的标准自由能变化ΔG°=-505009+145.03T,J.mol~(-1)(1780≤T≤2000°k)进而用热力学分析了GH36合金在含MgO或MgF_2渣系中电渣重熔合金中Si、Mn等成分对产生或保持合金中含有≥0.0020Wt％Mg的不可能性,提出了含Mg的GH36A合金电渣重熔时自耗电极中含有少量Al的必要性。研究了原始Al含量([Al]_0)、原始Mg含量([Mg]_0)以及熔渣成分对锭中Mg含量[Mg]的影响。当渣池温度为1690±10℃,0.32≤[Al]_0≤0.62Wt％,0.0035≤[Mg]_0≤0.0140Wt％,熔渣成分为0.10≤N_(MgO)≤0.30,0.05≤N_(Al_2O_3)≤0.21,N_(CaO)≤0.15范围,建立了GH36A合金电渣重熔控制[Mg]的关系式。 研究发现,含有适量的Mg、Al的GH36A合金可大幅度地提高合金在650℃,372.65×10~6Pa的缺口、光滑持久寿命,消除合金缺口敏感性。     

电渣重熔过程渣池磁流体力学行为数值模拟

建立了耦合电渣重熔过程渣池内电磁场、温度场和流场的数学模型,在考虑渣池内电磁力和热浮力对熔渣流动影响的基础上,分析了电渣重熔工艺(电极形貌、插入深度和电流强度)对渣池磁流体力学行为的影响规律.结果表明:当电磁力为主时,渣池内存在逆时针涡流;当热浮力为主时,渣池内存在顺时针涡流.电渣重熔电流5kA,频率50Hz,电极端部为平面时,渣池内同时存在逆时针和顺时针涡流,最大流速为005m/s;当电极端部为锥形时,渣池内部只存在顺时针涡流,最大流速为020m/s..增加电极插入深度和增大电流强度都会增强渣池内逆时针涡流;相反,则增强渣池内顺时针涡流.     

含铝钛合金电渣重熔中的渣系设计及脱氧热力学

以炉渣离子、分子共存理论为基础,1Cr21Ni5Ti钢为研究对象,Al为脱氧剂,根据熔渣-金属中各个组元的平衡反应和质量守恒,建立了脱氧热力学模型,并在脱氧基础上设计了渣系.在脱氧剂Al不同的加入量条件下对1Cr21Ni5Ti钢中的Si,Al,Mn的平衡质量分数和渣中Ti O2的需求量进行了计算,Ti O2的加入保证了钢中Ti的含量.结果表明:随脱氧剂Al的增加,Si,Al,Mn,Al2O3的平衡质量分数呈上升的趋势,Si O2,Fe O,Mn O以及渣系中Ti O2的设计量呈下降的趋势;当Al加入量达到0.2%后,渣中不稳定氧化物含量很低,大部分Al进入到钢液中,造成钢液增[Al].根据1Cr21Ni5Ti的Si,Al,Mn的成分要求,得到Al的最大加入量为0.15%/吨钢,此时渣系中Ti O2的设计量为4%,达到保钛的目的.     

不同熔化速率下的电渣重熔过程数值模拟分析

电渣重熔能提高钢锭的质量,从而满足特种行业的需要,其过程伴随着复杂的物理现象,存在着磁流体流动、传热和传质以及电化学等多方面的影响。通过耦合电磁以及流动和温度方程对电渣重熔过程的三维瞬态进行了数学模拟,研究了熔化速率对重熔过程的影响。结果表明:电流密度、焦耳热和电磁力都随着熔化速率的增大而增大,当熔化速率由14.4kg/h增加到27.0kg/h,电流密度、焦耳热和电磁力最大值的增大比例超过100%。随着熔化速率的增大,温度最大值有小幅的增加,而且速度最大值的增大幅度接近50%;金属熔池深度则由27mm增大到38mm,不利于保证铸坯的质量。     

镍基合金涂层炉内重熔研究

研究了炉内重熔加热温度、加热时间对镍基自熔合金粉末涂层组织的形貌的影响,测定并分析了基材至涂层的成分分布曲线,显微硬度曲线、熔合区成分等。研究结果表明,Ｎｉ２５熔点在１３００℃以上,Ｎｉ６０熔点在１０５０℃左右,炉内重熔的涂层－基材熔合区较宽;重熔时间对涂层的显微硬度值有没有明显的作用。     

Crustal growth at ～2.5 Ga in the North China Craton：evidence from whole-rock Nd and zircon Hf isotopes in the Huai＇an gneiss terrane

The Huai’an gneiss terrane mainly consists of TTG gneisses and dioritic gneisses. Laser in situ U-Pb dating of magmatic zircon cores indicates that protolith of these gneisses was formed at ~2.5 Ga. The TTG gneisses have positive εNd（t） values of 2.7 to 4.3, and most of the magmatic zircons have positive εHf（t） values of 2.0 to 8.3. These positive εNd（t） and εHf（t） values are both similar to those of the contemporaneous depleted mantle at 2.5 Ga. Moreover, the young Hf model ages of 2.44 to 2.73 Ga for the magmatic zircons are close to the timing of the zircons growth. The whole-rock εNd（t） values are lower in the dioritic gneisses （0.8 to 1.7） than in the TTG gneisses due to the involvement of ancient crust in its source. However, many magmatic zircons from the dioritic gneisses have similar εHf（t） values （2.0 to 7.9） to that of the coeval depleted mantle; their Hf model ages of 2.49 to 2.75 Ga are close to the U-Pb ages of zircons. The highest εHf（t） values are close to the value of the depleted mantle, and the relatively high εHf（t） values corresponds to the relatively young Hf model age. These Nd and Hf isotope features suggest that these two types of gneisses of the Huai’an gneiss terrane originated from the juvenile crust at ca. 2.5 Ga.