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51.
二维地电条件下充电法地形改正的一种方法   总被引:2,自引:0,他引:2  
本文首先讨论了充电法地形改正方法及存在的问题,提出了一种基于比值法思想的地改方法,经理论模型验算表明,有较好的地改效果  相似文献   
52.
本文从最大后验概率密度观点出发,在数据噪音向量和待求模型向量为具有零均值的独立高斯随机过程的假设前提下,建立起了随机反演的非线性系统方程;给出了模型方差估计的函数表达式,并在文章最后,证明了反演解的稀疏性,即解释了随机反演的输出解的高分辨率特征。文章在最小二乘反演方法的基础上,发展并完善了随机反演方法的理论基础;揭示了随机反演方法与最小二乘反演方法之间的本质区别;阐述了随机反演方法的优越性,并指出了其广阔的应用前景。  相似文献   
53.
详细介绍了内江松柏寨的七山、七堰、八景等自然景观;对以般若寺为代表的寺庙、寨门以及历代名人所留下的行踪和墨迹作了生动描写;提出以生态旅游为理念进行统一规划,并采取保护性开发的若干建议。  相似文献   
54.
A new method of detecting the vertical bearing capacity for single-pile with high strain is discussed in this paper. A heavy hammer or a small type of rocket is used to strike the pile top and the detectors are used to record vibration graphs. An expression of higher degree of strain (deformation force) is introduced. It is testified theoretically that the displacement, velocity and acceleration cannot be obtained by simple integral acceleration and differential velocity when long displacement and high strain exist, namely when the pile phase generates a whole slip relative to the soil body. That is to say that there are non-linear relations between them. It is educed accordingly that the force P and displacement S are calculated from the amplitude of wave train and (dynamic) P-S curve is drew so as to determine the yield points. Further, a method of determining the vertical bearing capacity for single-pile is discussed. A static load test is utilized to check the result of dynamic test and determine the correlative constants of dynamic-static P(Q)-S curve. Foundation item: Key projects of the tenth Five-year Plan of Yunnan Province (documented Yunnan district [2002]54-02-02) and Geophysical Society of Yunnan Province.  相似文献   
55.
刘建宏 《西北地质》2004,37(3):73-76
针对南泥湾油田特点。确定适合本区地质及油藏工程特点的工业油流标准,提高该类油田储量的计算精度。应用数值模拟、类比等方法。结果显示.南泥湾这类必须经过压裂改造的特低渗油藏.单井产量仍然按照双曲线递减规律;工业油流标准的确定,需要准确把握单井平均总投资、原油利润、收回单井总投资的单井产量等参数,在此基础上确定的工业油流标准更能满足生产需要,对储量计算、滚动开发建产、管理者决策具有十分重要的意义。  相似文献   
56.
小秦岭金矿含金石英脉中黄铁矿晶体的表面微形貌研究   总被引:1,自引:0,他引:1  
利用微分干涉显微镜、扫描电镜、透射电镜等对小秦岭金矿含金石英脉中黄铁矿晶体的表面微形貌进行了研究。黄铁矿晶体的{210}面上发育自由生长层,表明{210}面是F面,其生长机理受二维成核层生长所制约。除简单的五角十二面体外,其他形态黄铁矿晶体的{210}面上也发育有自由生长层。{210}面上的正条纹有些是由{100}面上生长层的边缘台阶在{210}面上叠堆形成,另一些正条纹则是{210}面上生长层边缘台阶堆叠的产物。透射电镜和电子衍射花样研究表明,负条纹黄铁矿晶体是由30~50nm大小的核团经自动定向附生作用形成,每个核团不是单晶体,而是由许多早先在溶液中形成的小微晶聚合而成。这些特征表明负条纹黄铁矿晶体是在溶液过饱和度极高和温度梯度小的理想环境中形成,它的形成与杂质无关。PBC理论和唐纳-哈克定律能较好地解释自然界中黄铁矿晶体{100}面上普遍发育自由生长层、而{210}面上自由生长层极为罕见的原因。除日本释迦内矿区黑矿之上的浮岩凝灰岩中产生出负条纹黄铁矿晶体外,在石英脉型金矿床中也有负条纹黄铁矿晶体产出。  相似文献   
57.
Taking continuous spatiotemporal in situ measurements with multi‐probes in fast‐flowing waters/rivers can be problematic because the sensors may be damaged by high shear forces and flotsam. To protect the multi‐probe and to enable easy access for the maintenance and calibration of the sensors, a special multi‐probe holder fixed in a hydrographic slot was developed. The validation of the probe system revealed a “memory effect” at short time scales (< 10 s) within sharp gradients caused by the overflow container of the multi‐probe rack keeping the sensors submerged in the sample water. Continuously recorded data (conductivity, temperature, pH, oxygen concentration and saturation, as well as in vivo fluorescence of chlorophyll‐a) from a research cruise on board the RV ALBIS along the river Elbe (river km 309) and entering the river Saale are presented. This river stretch upstream of the city of Magdeburg to the mouth of the Saale tributary was found to have a complex physicochemical character, which is attributable to the long mixing process of water from the river Saale and the river Elbe.  相似文献   
58.
The paper reports the results of experiments concerning the sorption/desorption processes, observed under laboratory conditions, in two types of coal extracted from operational coal-mines in Poland, using CH4 and CO2 to observe their relative inter-reaction with the coal samples when introduced in varying proportions and conditions. Numerous studies concerning the sorption/desorption phenomena have described the operational mechanisms and the relationship of mine gases to the organically-created coal-body in mines. The differences in the behaviour of certain gases is twofold: firstly the essentially different characteristics of CO2 and CH4, and secondly the structure of the coal-bed itself: its degree of metamorphism and content of macerals. From the results yielded, it was observed that the divergence of the isotherms of sorption of CH4 and other gases in comparison with the isotherms of sorption of CO2 and a CO2/CH4 mixture differed and that the curve on the sorption isotherm was more clearly distinct after the introduction of CO2 molecules to the system: coal with a higher degree of metamorphism—CH4, which is closely related to the rigidity of the structure according to the level of metamorphism. Since coals with higher carbon content exhibit lower molecular bonding than low-carbonised coals, the characteristic feature of the bonds in the first case is their mobility. Knowledge of the physical and chemical properties of hard coals, as well as their interaction with mining gases, is of great use in solving problems concerned with the extraction of methane from mines or its storage in goafs.  相似文献   
59.
60.
A new method was developed for analysing and delineating streambed water fluxes, flow conditions and hydraulic properties using coiled fibre‐optic distributed temperature sensing or closely spaced discrete temperature sensors. This method allows for a thorough treatment of the spatial information embedded in temperature data by creating a matrix visualization of all possible sensor pairs. Application of the method to a 5‐day field dataset reveals the complexity of shallow streambed thermal regimes. To understand how velocity estimates are affected by violations of assumptions of one‐dimensional, saturated, homogeneous flow and to aid in the interpretation of field observations, the method was also applied to temperature data generated by numerical models of common field conditions: horizontal layering, presence of lateral flow and variable streambed saturation. The results show that each condition creates a distinct signature visible in the triangular matrices. The matrices are used to perform a comparison of the behaviour of one‐dimensional analytical heat‐tracing models. The results show that the amplitude ratio‐based method of velocity calculation leads to the most reliable estimates. The minimum sensor spacing required to obtain reliable velocity estimates with discrete sensors is also investigated using field data. The developed method will aid future heat‐tracing studies by providing a technique for visualizing and comparing results from fibre‐optic distributed temperature sensing installations and testing the robustness of analytical heat‐tracing models. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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