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81.
煤层物性测井评价方法初探   总被引:6,自引:1,他引:5  
葛祥  李涛 《测井技术》2003,27(2):129-131
依据煤岩的赋存方式和结构特点,利用电阻率和井径测井资料在不同煤质结构的煤层所表现的差异性,建立了2个指标(即深侧向电阻率与微球电阻率之间的比值,井径与钻头之间的比值)对煤质结构进行了准确的识别。用多元回归的概率模型建立了煤岩镜质反射率的测井计算模式,其结果与已有的煤心分析数据对比,两者具有较好的一致性。在综合分析的基础上,对煤层的重要物性参数煤阶、煤质结构进行了测井评价。  相似文献   
82.
From chloromethylated polyimide, a useful starting material for modification of aromatic polyimides, a thermocurable transparent polyimide having acrylate side groups was prepared. In the presence of 1,8‐diazabicyclo[5,4,0]undec‐7‐ene, chloromethylated polyimide was esterified with acrylic acid to synthesize poly(imide methylene acrylate). The polymer was soluble in organic solvent, which makes it possible to prepare a planar film by spin coating. The polymer film became insoluble after thermal treatment at 230 °C for 30 min. Optical transparency of the film at 400 nm (for 1 µm thickness) was higher than 98 % and not affected by further heating at 230 °C for 250 min. Adhesion properties measured by the ASTM D3359‐B method ranged from 4B to 5B. Preliminary results of planarization testing showed a high degree of planarization (DOP) value (>0.53). These properties demonstrate that poly(imide methylene acrylate) could be utilized as a thermocurable transparent material in fabricating display devices such as TFT‐LCD. Copyright © 2004 Society of Chemical Industry  相似文献   
83.
In this paper, a new polysilicon CMOS self-aligned double-gate thin-film transistor (SA-DG TFT) technology is proposed and experimentally demonstrated. The self-alignment between the top- and bottom-gate is realized by a backlight exposure technique. The structure has an ultrathin channel region (300 /spl Aring/) and a thick source/drain region. Experimental results show that this technology provides excellent current saturation due to a combination of the effective reduction in the drain field and the full depletion of the ultrathin channel. Moreover, for n-channel devices, the SA-DG TFT has a 4.2 times higher on-current (V/sub gs/=20V) as compared to the conventional single-gate TFT. Whereas for the p-channel devices, the SADG TFT has a 3.6 times higher on-current (V/sub gs/=-20V) compared to the conventional single-gate device.  相似文献   
84.
众所周如,西藏地区是研究地球深部结构和构造的窗口,是研究大陆板块学说的重要场所,也是寻找热源和其它矿产资源的有利地区.因此,世界各国地学科学家都希望在本地区进行科学研究工作,或与我国科学工作者协作共同探索这一重要地区.中国和法国的地质、地球物理科学家经商讨共同组成“中法喜马拉雅山地质研究队”,对西藏中部广大地区进行地质、地球物理的科学研究工作.深部地震探测是地球物理研究中的重要内容.中法双方共同决定,在中国西藏南部的日喀则地区至北边的那曲地区作地震探测工作.为了探测地壳上地幔的结构,1981年在西藏的南部佩枯错至普莫雍错500公里的喜马拉雅山北麓——雅鲁藏布江地区进行了人工爆炸地震探测工作.本文是中法地质研究队合作的深部地震探测资料的解释结果.  相似文献   
85.
This paper presents recent efforts on the preparation of flexible polyhedral particles via concentrated emulsion templating polymerization in which the hydrophilic monomer (acrylamide) and hydrophobic monomer (butyl acrylate) are polymerized simultaneously in the continuous and dispersed phase, respectively. Such templating polymerization has been enhanced in our systems owing to the introduction of acrylamide monomer and their higher polymerization rate in continuous phase as compared with butyl acrylate in dispersed phase. Diffusion between the different phases was also inhibited. Furthermore, the stability of the concentrated emulsion and the molecular weight of the produced poly(butyl acrylate) were found to be significantly affected by the amount of redox initiator. The morphology of the particles could be controlled by varying the volume fraction of the dispersed phase and the polyhedral particles were achieved at higher volume fraction. Copyright © 2005 Society of Chemical Industry  相似文献   
86.
A photochromic nanocomposite based on Keggin structure phosphomolybdic acid (PMoA) well dispersed in polyethyleneglycol (PEG) was fabricated. TEM image showed that PMoA nanoparticles with narrow size distribution were finely dispersed in polymer matrix. FT-IR results showed that the Keggin geometry of polyoxometalates was still preserved inside the composites and strong coulombic interaction was built between PMoA and polymer matrix. Under UV irradiation, the film was reduced photochemically to yield a blue species, which was in accordance with a charge-transfer mechanism.  相似文献   
87.
88.
A block‐oriented approximate feedback linearization for control of a pneumatic cylinder positioning system is introduced and a rather detailed discussion is presented on the uncertain linearization residual characterization. It is shown that making use of the characterized gain–phase information of the linearized system leads to a more reasonable trade‐off between performance and stability in the QFT control design and thus results in high control performance. Simulation and experimental results are shown. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
89.
In this paper, a methodology is developed to use data acquisition derived from condition monitoring and standard diagnosis for rehabilitation purposes of transformers. The interpretation and understanding of the test data are obtained from international test standards to determine the current condition of transformers. In an attempt to ascertain monitoring priorities, the effective test methods are selected for transformer diagnosis. In particular, the standardization of diagnostic and analytical techniques are being improved that will enable field personnel to more easily use the test results and will reduce the need for interpretation by experts. In addition, the advanced method has the potential to reduce the time greatly and increase the accuracy of diagnostics. The important aim of the standardization is to develop the multiple diagnostic models that combine results from the different tests and give an overall assessment of reliability and maintenance for transformers.  相似文献   
90.
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