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21.
Fault related folds and fractures, which always improve reservoirs and trap capacity, especially in the oil and gas fields in western China, are of extreme importance for oil and gas exploration. Based on four assumptions and fault related fold theory, we propose four conceptual models for fracturing in fault related folds, i.e., a simple-step parallel fault bend anticline, a simple-step parallel fault propagation anticline, a multiple-bend fault-bend fold and a break-forward imbricate. Fracture conditions depend on structural evolution and specific site conditions. A case study of the Kulongshan Anticline in the Jiuquan Basin shows that our conceptual models match reality data very well.  相似文献   
22.
In this work, the synthesis of nanocrystalline Ce0.9Zr0.1O2 powders via the gel-combustion method, using different fuels, and following either stoichiometric or non-stoichiometric pH-controlled routes is investigated. The objective is to evaluate the effect of synthesis conditions on the textural and morphological properties, and the crystal structure of the synthesized materials. The solids were characterized by nitrogen physisorption, Scanning Electron Microscopy (SEM), X-ray powder diffraction (XPD), and Carbon-Hydrogen-Nitrogen Elemental Analysis (CHN).All the powders exhibited nanometric crystallite size, fluorite-type structure and negligible carbon content. Synthesis conditions strongly affect the average crystallite size, the degree of agglomeration, the specific surface area and the pore volume. Our results indicate that, by controlling the synthesis conditions it is possible to obtain solids with custom-made morphological properties.  相似文献   
23.
SiO2 hollow spheres with movable Fe3O4 core were obtained by exposing the pre-synthesized Fe3O4SiO2 particles (with an adsorption interlayer of ethylene glycol) under the irradiation of electron beam inside transmission electron micrograph (TEM). In the formation process, the evaporation of adsorbed ethylene glycol and the evolution of amorphous SiO2 layer played important roles, and that should be attributed to the high temperature and trapped charges induced by the irradiation of electron beam. This work provided a new route to obtain particles with movable core structure and extended the applications of electron beam.  相似文献   
24.
This paper discusses the results of geophysical and chemical investigations carried out in a chemical munition dumpsite in the southern Baltic Sea, east of the island of Bornholm. After WW2 over 32,000 tons of chemical war material was dumped here including shells and bombs as well as small drums and containers. The geophysical investigations combined very-high-resolution seismics and gradiometric measurements. The results indicate the presence of a large number of objects buried just below the seafloor. The size of the objects and their distribution, with a marked increase in density towards the center of the dumpsite, suggests that we are dealing with dumped war material. Sediment and near-bottom water samples, taken within the dumpsite and in the surrounding area, were analysed for the presence of various chemical warfare agents (CWA) including Adamsite, Clark, sulphur mustard, tabun, chlorobenzene and arsine oil. The results indicate a widespread contamination that reaches far beyond the dumpsite boundary. CWA degradation products were found in most of the sediment samples. The contamination was mostly related to arsenic containing compounds; only one sample indicated the presence of sulfur mustard. Although the correlation between detected objects and CWA concentrations is not always straightforward, the overall results suggest that a lot of the dumped war material is leaking and that over the years the contamination has reached the seafloor sediments.  相似文献   
25.
临时用电市场是电力公司非常优质的市场,发展临时用电市场可给供电企业带来明显的效益,也有助于提高市场占有率,同时为客户提供了生产电力,降低了生产成本。临时用电比较分散、隐蔽,信息不易掌握,供电存在难度。以甘肃省为例,通过分析临时用电的特点及存在的问题,提出了适合于开拓临时用电市场的具体措施。  相似文献   
26.
Low-temperature crystallized ZnO thin film was achieved by sol–gel process using zinc acetate dihydrate and 2-methoxyethanol as starting precursor and solvent, respectively. Ag nanoparticles were prepared with uniform size at 4.4 nm by spontaneous reduction method of Ag 2-ethylhexanoate in dimethyl sulfoxide (DMSO). The optical and electrical properties of ZnO thin films containing various contents of Ag-nanoparticles were monitored. Light scattering and charge emission and scattering behaviors of Ag nanoparticles in ZnO film were found. The incorporation of Ag nanoparticles into Al-doped ZnO film was also investigated. The optical transmittance was not degraded but the increase of electrical sheet resistance was found. The effect of Al-dopant on the transmittance and electrical sheet resistance of ZnO film was found too great to distinguish the positive effect of the incorporation of Ag nanoparticles into Al-doped ZnO thin films.  相似文献   
27.
Preparation of ultra fine nickel-copper bimetallic powder for BME-MLCC   总被引:1,自引:0,他引:1  
The preparation of ultra fine nickel-copper bimetallic powder with two-stage chemical reduction method was investigated. Reductive sugar and hydrazine hydrate were employed as reducing agent in different reductive stage, respectively. Reaction of CuSO4·5H2O with reductive sugar at 70 °C gives cuprous oxide and copper particles, then as-prepared mixture and nickelous hydroxide were reduced by hydrazine hydrate, and nickel-copper powder having excellent dispersibility was prepared. Influences of nickel added on composition and dispersibility of powder were studied. TG/DTG/DTA of nickel-copper powder, which is stable in room temperature, were discussed with thermal analyzer. Relation of nickel content to oxidation temperature was investigated. Ni-Cu bimetallic powder particles have a fully coated structure when nickel content is up to 30%. As-prepared nickel-copper powder was applied in base metal electrode-multilayer ceramic capacitor (BME-MLCC). The end termination has high adhesion force, fairly good densification, low resistivity, excellent solderibility behavior and resistance behavior to soldering.  相似文献   
28.
洪泽凹陷为一典型的箕状凹陷,根据其特点将该凹陷及其次凹分为陡断带、深凹带、中部断裂构造带(或枢纽带)和缓坡带4个构造单元。在系统总结洪泽凹陷生储盖发育及组合特点基础上,阐述了油藏发育类型、分布与4个构造单元的相互关系,指出了洪泽凹陷下步的勘探领域和方向。  相似文献   
29.
详细分析垢层形成的原因和清除方法的选择以及酸洗除垢的全过程,一方面使制约装置正常运行负荷的问题得到较好的解决,另一方面也有效地防止了管线、设备的腐蚀、堵塞直至出现超温、超压而发生的火灾爆炸事故。  相似文献   
30.
One of the many remarkable properties of diamond is its thermal conductivity, about five times that of copper and the highest of all known materials. The high thermal conductivity in combination with the relative ease of diamond film growth by chemical vapor deposition process makes the material suitable for many applications such as thermal management in high power electronic circuits. For thermal managements applications, various processing steps are needed for the diamond films, such as the metallization for reliable solder bonding, metallurgical processes for planarizing of the faceted growth surface and removal of fine-grained diamond regions with poor thermal conductivity. This paper will review the properties and processing of diamond films for thermal management applications.  相似文献   
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