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Laboratory insights into the effects of methane hydrate on the anisotropic joint elastic-electrical properties in fractured sandstones

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Petroleum Science 2023年第2期20卷 803-814页

作者： Sheng-Biao Liu tong-Cheng han Li-Yun Fu Shandong Provincial Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong266580China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and TechnologyQingdaoShandong266071China

Fractured hydrate-bearing reservoirs show significantly anisotropic geophysical properties. The joint application of seismic and electromagnetic explorations is expected to accurately assess hydrate resources in the fractured reservoirs. However, the anisotropic joint elastic-electrical properties in such reservoirs that are the key to the successful application of the joint explorations, remain poorly understood. To obtain such knowledge, we designed and implemented dedicated laboratory experiments to study the anisotropic joint elastic-electrical properties in fractured artificial silica sandstones (with fracture density of about 6.2%, porosity of approximately 25.7%, and mean grainsize of 0.089 mm) with evolving methane hydrate. The experimental results showed that the anisotropic compressional wave velocities respectively increased and decreased with the forming and dissociating hydrate, and the variation in the increasing trend and the decreasing extent of the velocity perpendicular to the fractures were more significant than that parallel to the fractures, respectively. The experimental results also showed that the overall decreasing trend of the electrical conductivity parallel to the fractures was steeper than that perpendicular to the fractures during hydrate formation, and the general variations of the two conductivities with complex trend were similar during hydrate dissociation. The variations in the elastic and electrical anisotropic parameters with forming and dissociating hydrate were also found to be distinct. Interpretation of the experimental results suggested that the hydrate binding to the grains evolved to bridge the surfaces of fractures when saturation exceeded 10% during hydrate formation, and the bridging hydrate gradually evolved to floating in fractures during dissociation. The experimental results further showed that the anisotropic velocities and electrical conductivities were correlated with approximately consistent trends of different

关键词： Fractured hydrate reservoirs Elastic anisotropy Electrical anisotropy Joint elastic-electrical properties Hydrate distribution

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军队院校装备课程群建设探索与实践

大学教育 2024年第2期 33-36页

作者：韩统唐上钦王渊空军工程大学航空工程学院陕西西安710038

立足军队院校装备课程的特点及岗位需求,采用课程群组的概念,开展航空军械装备课程群建设探索与实践。在改革探索实践中,坚持“工作过程导向”的职业教育理念,基于知识技能融合、能力素养主导,构建了全新课程教学体系和实战化、信息化... 详细信息

立足军队院校装备课程的特点及岗位需求,采用课程群组的概念,开展航空军械装备课程群建设探索与实践。在改革探索实践中,坚持“工作过程导向”的职业教育理念,基于知识技能融合、能力素养主导,构建了全新课程教学体系和实战化、信息化教学条件,探索了多样化的教学方法及考核评价方式,重视课程思政元素在课程群中的有机融合,逐渐形成了教学资源丰富、教学效果突出、建设成果丰硕的课程群。

关键词：岗位任职需求装备课程群课程建设

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浙江省船舶和港口大气污染防治对策研究

综合运输 2024年第8期46卷 168-172,177页

作者：王本梅韩通廖青梅浙江省交通运输科学研究院浙江杭州310000

本文通过搜集浙江省船舶和港口能源消耗,采用燃料法进行大气污染物排放计算,编制浙江省船舶和港口大气污染物排放清单,研究船舶和港口大气污染物排放特征,分析浙江省船舶和港口污染防治现状与存在问题,提出污染防治对策,为管理者开展船... 详细信息

本文通过搜集浙江省船舶和港口能源消耗,采用燃料法进行大气污染物排放计算,编制浙江省船舶和港口大气污染物排放清单,研究船舶和港口大气污染物排放特征,分析浙江省船舶和港口污染防治现状与存在问题,提出污染防治对策,为管理者开展船舶和港口大气污染防治提供参考。

关键词：船舶和港口大气污染防治排放清单

Influence of Trace Alloying Elements on Corrosive Resistance of Cast Stainless Steel

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Journal of Iron and Steel Research International 2005年第5期12卷 52-57页

作者： DUAN han-qiao YAN Xiang WEI Bo-kang LIN han-tong Huazhong University of Science and Technology Wuhan 430074 China

The influences of trace alloying elements niobium, vanadium and zirconium on the corrosive resistance of 18 8 type cast stainless steel have been studied in detail by orthogonal design experiments. The results show that zirconium is mainly in the form of compound inclusions, which is unfavorable to promote the corrosive resistance of the cast stainless steel. It can alleviate the disadvantageous influence of carbon addition on corrosive resistance when some elements such as vanadium and niobium exist in the steel, and niobium has a remarkable influence on the intergranular corrosive resistance but unobvious on the pitting corrosion, and vanadium has a slightly favorable influence on the corrosive resistance of the steel.

关键词： orthogonal design stainless steel trace alloying element corrosive resistance

Diffusion tensor imaging with multiple diffusion-weighted gradient directions

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Neural Regeneration Research 2011年第1期6卷 66-71页

作者： Shan Jiang Meixia Liu tong han Weihua Liu School of Mechanical Engineering Tianjin University Tianjin 300072 China Medical Image Evaluation Center Tianjin Huanhu Hospital Tianjin 300060 China

Diffusion tensor MRI （DT-MRI or DTI） is emerging as an important non-invasive technology for elucidating intemal brain structures. It has recently been utilized to diagnose a series of diseases that affect the integrity of neural systems to provide a basis for neuroregenerative studies. Results from the present study suggested that neural tissue is reconstructed with multiple diffusion-weighted gradient directions DTI, which varies from traditional imaging methods that utilize 6 gradient directions. Simultaneously, the diffusion tensor matrix is obtained by multiple linear regressions from an equation of echo signal intensity. The condition number value and standard deviation of fractional anisotropy for each scheme can be used to evaluate image quality. Results demonstrated that increasing gradient direction to some extent resulted in improved effects. Therefore, the traditional 6 and 15 directions should not be considered optimal scan protocols for clinical DTI application. In a scheme with 20 directions, the condition number and standard deviation of fractional anisotropy of the encoding gradients matrix were significantly reduced, and resulted in more clearly and accurately displayed neural tissue. Results demonstrated that the scheme with 20 diffusion gradient directions provided better accuracy of structural renderings and could be an optimal scan protocol for clinical DTI application.

关键词： diffusion tensor imaging neural tissue tensor matrix multiple linear regression condition number

A Chaos Sparrow Search Algorithm with Logarithmic Spiral and Adaptive Step for Engineering Problems

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Computer Modeling in Engineering & Sciences 2022年第1期130卷 331-364页

作者： Andi Tang Huan Zhou tong han Lei Xie Aeronautics Engineering College Air Force Engineering UniversityXi’an710038China

The sparrow search algorithm(SSA)is a newly proposed meta-heuristic optimization algorithm based on the sparrowforaging *** to other meta-heuristic algorithms,SSA has problems such as slowconvergence speed and difficulty in jumping out of the local *** order to overcome these shortcomings,a chaotic sparrow search algorithm based on logarithmic spiral strategy and adaptive step strategy(CLSSA)is proposed in this ***,in order to balance the exploration and exploitation ability of the algorithm,chaotic mapping is introduced to adjust the main parameters of ***,in order to improve the diversity of the population and enhance the search of the surrounding space,the logarithmic spiral strategy is introduced to improve the sparrow search ***,the adaptive step strategy is introduced to better control the process of algorithm exploitation and *** best chaotic map is determined by different test functions,and the CLSSA with the best chaotic map is applied to solve 23 benchmark functions and 3 classical engineering *** simulation results show that the iterative map is the best chaotic map,and CLSSA is efficient and useful for engineering problems,which is better than all comparison algorithms.

关键词： Sparrow search algorithm global optimization adaptive step benchmark function chaos map

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灰霉菌侵染对红提表皮蜡质和采后品质的影响

食品研究与开发 2024年第11期45卷 8-15页

作者：于姝莉吕云皓韩彤江英石河子大学食品学院新疆石河子832003

以红提为试验原料,研究灰霉菌对常温(25.0±0.5)℃贮藏红提表皮蜡质主要化学组分及其贮藏品质的影响。气相色谱-质谱法(gas chromatography-mass spectrometry,GC-MS)分析红提果实蜡质主要成分,发现在整个贮藏期间,酸类、酯类相对含量较... 详细信息

以红提为试验原料,研究灰霉菌对常温(25.0±0.5)℃贮藏红提表皮蜡质主要化学组分及其贮藏品质的影响。气相色谱-质谱法(gas chromatography-mass spectrometry,GC-MS)分析红提果实蜡质主要成分,发现在整个贮藏期间,酸类、酯类相对含量较高,醇类、烷烃、萜类、醛类物质次之。随着贮藏时间的延长,两组果实的烷烃、萜类、醛类相对含量减少。灰霉菌侵染会导致表皮蜡质组成成分相对含量的降低,进而减少其表皮蜡质含量。贮藏期间,灰霉病加重红提果实的失重和软化,降低可溶性固形物、可滴定酸、总酚和总黄酮的含量。蜡质主要组成成分与品质指标相关性分析表明红提表皮蜡质是影响其贮藏品质的重要因素。

关键词：红提表皮蜡质组成成分灰霉菌贮藏品质

Insights into the multiple applications of modified polyacrylamide as oilfield corrosion inhibitor and water phase tackifier

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Petroleum Science 2022年第1期19卷 397-408页

作者： tong han Ji-Xiang Guo Qing Zhao Tao Shen Shi-Ling Zhang Unconventional Natural Gas Institute China University of PetroleumChangpingBeijing102249People's Republic of China State Key Laboratory of Heavy Oil Processing and College of Science China University of PetroleumChangpingBeijing102249People's Republic of China

In order to obtain a multifunctional oilfield agent with both corrosion inhibition and oil displacement functions,a polymer with benzene ring structures is synthesized based on polyacrylamide(PAM)and used as inhibitor for the first *** including electrochemistry,weight loss and theoretical calculations are used to study the inhibition effect for P110 steel in 1.0 M *** experimental results show that the modified polymer poly-(Z)-N-benzylidenepropionamide(PBAM)has excellent inhibition effects,and the maximum efficiency can reach 90.62%in impedance spectroscopy *** benzene ring structure added in the modified polymer providesπelectrons for the adsorption of inhibitor on metal surface,strengthens the adsorption,and thus brings a better corrosion inhibition *** addition to the corrosion inhibition performance,the viscosity-increasing effect of PBAM is *** results show that the addition of benzene ring not only enhances the corrosion inhibition effect,but also brings temperature resistance to the ***,the salt tolerance of the polymer is affected,the synthesized PBAM which viscosity can above 500 m Pa s at 140℃ is suitable for high temperature and low salinity *** modified polyacrylamide has satisfactory corrosion inhibition and oil displacement performance,which provides a new idea for the development of oilfield chemistry.

关键词： Corrosion inhibitor Polymer Multifunctional pharmacy Computational study

Tri-linear interpolation-based cerebral white matter fiber imaging

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Neural Regeneration Research 2013年第23期8卷 2155-2164页

作者： Shan Jiang Pengfei Zhang tong han Weihua Liu Meixia Liu School of Mechanical Engineering Tianjin University Medical Image Evaluation Center Tianjin Huanhu Hospital

Diffusion tensor imaging is a unique method to visualize white matter fibers three-dimensionally, non-invasively and in vivo, and therefore it is an important tool for observing and researching neural regeneration. Different diffusion tensor imaging-based fiber tracking methods have been already investigated, but making the computing faster, fiber tracking longer and smoother and the details shown clearer are needed to be improved for clinical applications. This study proposed a new fiber tracking strategy based on tri-linear interpolation. We selected a patient with acute infarction of the right basal ganglia and designed experiments based on either the tri-linear interpolation algorithm or tensorline algorithm. Fiber tracking in the same regions of interest （genu of the corpus callosum） was performed separately. The validity of the tri-linear interpolation algorithm was verified by quan- titative analysis, and its feasibility in clinical diagnosis was confirmed by the contrast between tracking results and the disease condition of the patient as well as the actual brain anatomy. Statis- tical results showed that the maximum length and average length of the white matter fibers tracked by the tri-linear interpolation algorithm were significantly longer. The tracking images of the fibers indicated that this method can obtain smoother tracked fibers, more obvious orientation and clearer details. Tracking fiber abnormalities are in good agreement with the actual condition of patients, and tracking displayed fibers that passed though the corpus callosum, which was consistent with the anatomical structures of the brain. Therefore, the tri-linear interpolation algorithm can achieve a clear, anatomically correct and reliable tracking result.

关键词： neural regeneration neuroimaging diffusion tensor imaging tri-linear interpolation tensor algorithmwhite matter fiber fiber tracking magnetic resonance imaging grants-supported paper neuroregeneration