巨野煤田彭庄煤矿首采区减少煤损方法简析

山东鲁能菏泽煤电开发有限公司彭庄煤矿位于巨野煤田北部,是巨野煤田7个生产和在建煤矿（包括梁宝寺、彭庄、郭屯、赵楼、龙崮、万福、郓城等煤矿）的第一对投产的矿井。2006年8月开始试生产,2007年3月正式投产。彭庄煤矿2007年底核实保有资源量为12698．9万t,     

Fitting of magnetic measurements of Swarm satellites based on 3D surface spline model

This study utilizes the 62208000 Swarm satellite data to establish a high-precision main magnetic field at the height of the satellites in China and its adjacen...     

Supernova β~- decay of nuclides ~(53)Fe,~(54)Fe,~(55)Fe and ~(56)Fe in strongly screened plasma

Electron screening has strong effects on electron energy and threshold energy of the beta decay reaction.In this paper,we study β~-decay rates of some iron isotopes.The beta decay rates increase by about two orders of magnitude due to electron screening.Strongly screened beta decay rates due to Q-value correction are more than one order of magnitude higher than those without Q-value correction.     

1987—2018年西双版纳橡胶林时空变化及其线状特征

基于1987—2018年西双版纳30 m分辨率橡胶林数据集,利用叠置、缓冲区等GIS空间分析方法,对比分析了过去32年橡胶林沿道路、河流和边境线的空间变化特征与区域差异。结果表明：1) 1987—2018年,西双版纳橡胶种植面积在道路、河流沿线5 km以内分别增加了1 874.6和1 484.6 km²,在边境地区(国境线20km缓冲带)增加了1 393.1 km²。2)从道路沿线看,受橡胶种植可达性和交通运输影响,过去32年道路5 km缓冲带内的橡胶林平均占比超过九成。3)从河流沿线看,因灌溉和水源等需求,过去32年河流沿线5 km缓冲带内橡胶林平均占比69.7%。值得注意的是,受天然橡胶价格持续低迷、城镇化与生态环境保护等影响,2010年河流沿线橡胶林种植面积开始下降,沿线2 km内表现尤为显著。4)从边境地区看,西双版纳橡胶林种植呈明显趋边性特征,跨境种植频繁。过去32年边境沿线地区橡胶林平均占比55.6%,且由1987年的35.4%上升到2018年的66.2%,其中,在中缅边境的扩张面积和速率高于中老边境。     

The role of metal sulfates in thermochemical sulfate reduction (TSR) of hydrocarbons: Insight from the yields and stable carbon isotopes of gas products

The mechanism of thermochemical sulfate reduction (TSR) was investigated by separately heating n-C₂₄ with three different sulfates (CaSO₄, Na₂SO₄, MgSO₄) in sealed gold tubes at 420 °C and measuring the stable carbon isotope values of hydrocarbon (C₁-C₅) and non-hydrocarbon (CO₂) products. Extensive TSR was observed with the MgSO₄ reactant as reflected by increasing concentrations of H₂S, ¹³C depleted CO₂ and relatively low concentrations of H₂ (compared to the control). H₂S yields were already very high at the first monitoring time (12 h) when the temperature had just reached 420 °C, suggesting that TSR had commenced well prior to this temperature. Only trace amounts of n-C₂₄ and secondary C₃-C₅ alkanes were detected at 12 h, reflecting the efficient TSR utilization of the reactant and lower molecular weight alkane products. Ethane levels were still relatively high at 12 h, but declined thereafter as it was subject to TSR in the absence of higher molecular weight alkanes which had already been utilized. Methane yields were consistently high throughout the 48 h MgSO₄ treatment. The temporal decrease in the concentrations of alkanes available for TSR may also contribute to the sharp enhancement of CO₂ after 36 h. Absence or dampening of the molecular and isotopic trends of MgSO₄ TSR was observed with Na₂SO₄ and CaSO₄ respectively, directly reflecting the levels of TSR reached using these sulfate treatments.For all treatments, the δ¹³C values of C_1-5n-alkanes showed an increase with both molecular weight and treatment time. MgSO₄ TSR led to a 5-10‰ increase in the δ¹³C values of the C₁-C₅ hydrocarbons and a 20‰ decrease in the δ¹³C value of CO₂. The significant ¹³C depletion of the CO₂ may be due to co-production of ¹³C enriched MgCO₃, although this remains unproven as the δ¹³C of MgCO₃ was not measured. The difference in the δ¹³C values of ethane and propane (Δδ¹³C_EP) increased in magnitude with the degree of TSR, and this trend could be used to help evaluate the occurrence and extent of TSR in subsurface gas reservoirs.     

长白山及邻区地壳、上地幔顶部三维速度结构

根据沿长白山布设的宽频带流动地震台站及吉林省地震台网所记录的近震P波走时数据,利用层析成像方法对长白山及邻区（39°N-45°N、122°E-130°E）深至40 km的地壳和上地幔顶部三维速度结构进行了研究。结果表明：地震的发生和分布多集中于断裂等复杂地质构造。利用较高分辨率的地壳、上地幔顶部三维速度结构证实了长白山火山区岩浆囊存在,并推测岩浆囊的位置位于火山口的西南方向,深度为10~40 km。壳内岩浆囊分布对进一步解释、认识火山灾害提供了重要的深部信息。     

干湿循环下原状黄土抗压强度试验研究

黄土是干旱、半干旱条件下形成的,具有特殊结构的土,季节性的降雨和蒸发作用必将引起其力学性质和结构改变,从而造成其强度降低和变形增大的问题。通过单轴抗压强度试验探讨了黄土抗压强度与含水率、干湿循环次数的变化规律,借助SEM图像定性和定量分析了其强度变化的微观机制。试验结果表明：黄土单轴抗压强度随含水率的减小表现为非线性的增大;随干湿循环次数的增加而减小,经历多次干湿循环后趋于稳定;含水率增大和干湿循环次数的增加不仅仅会使得粗颗粒的接触方式改变与胶体物质和腐殖质数量减少,还会使得土体孔隙直径增大,大、中孔隙所占百分比之和明显增多,进而从微观结构阐述了土体宏观强度的变化规律。     

三角剪切断层传播褶皱在祁连山北缘断裂中的应用:以黑河口断层为例

逆冲断层运动学过程研究可为造山作用和盆地演化提供重要的信息。位于青藏高原东北缘的祁连山北缘逆冲断裂（NFT）是一条主要的边界断裂,控制着祁连山晚新生代以来的隆升变形,但对于该断裂系统的运动学过程缺乏研究。甘肃张掖西南莺落峡附近,黑河口断层（祁连山北缘断裂的一部分）穿过红沙沟并导致其阶地面错断和褶皱变形。为了研究该区域褶皱变形特征和断层运动学过程,我们首先在红沙沟区域进行了详细的野外考察并对变形的地层和阶地面进行了测量,然后通过数值模拟方法来验证褶皱模型。红沙沟保存有9级河流阶地,利用差分GPS对阶地面的高程进行了测量,同时在野外测量了部分地层的产状。多处断层剖面表明该区域变形属于基底卷入的构造类型,另外变形的阶地面在近断层处表现出明显的褶皱形态。结合阶地面变形特征以及地层的变形,三角剪切断层传播褶皱模型被初步用于该区域构造变形的解释。模型模拟得到自T5、T6和T7形成以来断层滑动量分别是 44±7m、59±10m和 164±28m;结合T6年代得到自约9万年以来该断层的平均滑动速率为 0.68±0.19mm/a,垂直分量为 0.58±0.13mm/a。根据地层与阶地变形特征,并结合模型模拟结果,我们认为祁连山山前基底断层卷入的构造中,在断层出露地表之前,断层顶端存在一个分散式的三角形变形区,区域的应力状态控制着下伏地层和上覆地貌面的褶皱变形。     

Combined perturbation on near-earth satellite orbits

Using a semi-analytical method, we have obtained a first-order solution of the equations of motion of near-Earth satellites under the combined perturbing effect due to Earth's figure and air drag.