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Chinese Journal of Structural Chemistry 2016年第2期35卷 298-306页

作者： LI Xiu-Mei SUN Ming PAN Ya-Ru JI Jian-ye Faculty of Chemistry Tonghua Normal University College of Plant Science Jilin Agriculture Science and Technology College

A new complex[Co（NIPH）（mbix）]n（1,H2NIPH = 5-nitroisophthalic acid,mbix =l,3-bis（imidazol-l-ylmethyl）benzene） has been hydrothermally synthesized and structurally characterized by elemental analysis,IR spectrum,UV spectrum,TG and single-crystal X-ray *** crystals crystallize in the triclinic system,space group P1 with a = 8.3797（8）,b= 10.2522（10）,c= 13.4244（13） A,α=94.820（2）,β=108.105（2）,γ=104.816（2）°,V=1042.84（17） A^3,C（22）H（17）CoN5O6,Mr = 506.34,Dc = 1.613 g/cm^3,F（000） = 518,Z = 2,μ（MoKα） =0.876 mm^（-1）,the final R = 0.0505 and wR = 0.1254 for 3267 observed reflections（I〉2σ（I））.The structure of 1 exhibits a two-dimensional network structure and is extended into a three-dimensional supramolecule through hydrogen bonds and n-n *** addition,Natural Bond Orbital（NBO） analysis was performed by using the PBE0/LANL2 DZ method built in Gaussian 09 *** calculation results showed obvious covalent interactions between the coordinated atoms and Co（Ⅱ） ion.

关键词： hydrothermal synthesis crystal structure cobalt complex natural bond orbital

Study of evaluation method for the overseas oil and gas investment based on risk compensation

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Petroleum Science 2020年第3期17卷 858-871页

作者： Zu-Xin Li Jian-ye Liu Dong-Kun Luo Jian-Jun Wang School of Business Administration China University of Petroleum BeijingBeijing 102249China Department of Overseas New Ventures Assessment Research Institute of Petroleum Exploration and DevelopmentBeijing 100083China

The overseas oil and gas investment evaluation is one of the core tasks in overseas investment of oil and gas companies,among which risk evaluation and benefit evaluation are the most *** paper sets forth transmission paths of risk factors to the investment benefit by identifying 14 overseas oil and gas investment risks in four *** the basis of the concept of risk compensation,different compensation mechanisms specific to each risk are *** risk and benefit are integrated objectively to develop a comprehensive evaluation model by correcting the recoverable reserve,adjusting benefit evaluation parameters such as investments on exploration and development,and compensating for the changes in risk factors with time through dynamic discount ***,two cases studies,namely the evaluations of Project A in Sudan and comparison among Blocks A–G,are used to describe usage method and applicable scope of such evaluation model,*** to the results,oil price is a key influencing factor for enterprise internal risk and industrial *** compensation reduces comprehensive benefit of overseas oil and gas investment and undermines the investment feasibility and priority of *** research findings of this paper are free from the effects of some subject factors and avoid multi-objective decision making,and also avoid the undesired repeated calculation of risk factors.

关键词： Overseas oil and gas investment Investment evaluation Risk compensation Dynamic discount rate Comprehensive benefit

Adaptive foreground and shadow segmentation using hidden conditional random fields

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 586-592页

作者： CHU Yi-ping ye Xiu-zi QIAN Jiang ZHANG Yin ZHANG San-yuan School of Computer Science State Key Lab. of CAD ＆ CG Zhejiang University Hangzhou 310027 China

Video object segmentation is important for video surveillance, object tracking, video object recognition and video editing. An adaptive video segmentation algorithm based on hidden conditional random fields (HCRFs) is proposed, which models spatio-temporal constraints of video sequence. In order to improve the segmentation quality, the weights of spatio-temporal con- straints are adaptively updated by on-line learning for HCRFs. Shadows are the factors affecting segmentation quality. To separate foreground objects from the shadows they cast, linear transform for Gaussian distribution of the background is adopted to model the shadow. The experimental results demonstrated that the error ratio of our algorithm is reduced by 23% and 19% respectively, compared with the Gaussian mixture model (GMM) and spatio-temporal Markov random fields (MRFs).

关键词： Video segmentation Shadow elimination Hidden conditional random fields (HCRFs) On-line learning

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基于球面波的地震记录合成方法及AVO分析

中国石油大学学报（自然科学版） 2009年第3期33卷 49-52,75页

作者：黄饶陈小宏李景叶中国石油大学CNPC物探重点实验室北京102249 中国石油大学油气资源与探测国家重点实验室北京102249 中国石油大学油气成藏机理教育部重点实验室北京102249

在子波具有Rayleigh形式假设基础上,利用Laplace变换对基于球面波理论的地震AVO(振幅随偏移距变化)方程进行积分变换,通过半解析的方法,使得计算球面波反射系数得到有效简化,并对球面扩散、近场影响补偿及权函数进行分析,最后进行理论... 详细信息

在子波具有Rayleigh形式假设基础上,利用Laplace变换对基于球面波理论的地震AVO(振幅随偏移距变化)方程进行积分变换,通过半解析的方法,使得计算球面波反射系数得到有效简化,并对球面扩散、近场影响补偿及权函数进行分析,最后进行理论模型的计算与分析。结果表明,球面波反射系数不仅与入射角度有关,还受地震子波频率和储层埋藏深度影响。在临界角附近,基于球面波理论反射系数计算结果较基于平面波理论更为合理。

关键词： AVO 球面波 Rayleigh子波权函数 Zoeppritz

Lamellar metal-organic complex and its rod-like nanoparticles prepared with ultrasonic technique

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Science China Chemistry 2008年第9期51卷 829-833页

作者： LU XiaoMing WANG Ting HAN Li PANG XiaoLi ye ChaoHui Department of Chemistry Capital Normal UniversityBeijing 100037China Wuhan Institute of Physics and Mathematics Chinese Academy of SciencesWuhan 430071China

Metal-organic complex (H3NCH2CH2NH2)3[MoO2(OC6H4O)2] with a lamellar morphology has been syn- thesized. Its crystal structure was confirmed by single-crystal X-ray diffraction. The morphology of the crystal was observed by scanning electron microscopy (SEM). The metal-organic nanoparticles have been prepared by using an ultrasonic method. The morphology of the as-prepared nanoparticles was observed by transmission electron microscopy (TEM). The possible formation mechanism has also been proposed.

关键词： metal-organic complex nanoparticle ultrasonic technique

Preparation and Characterization of Polymeric PVDF/PDDA Ultrathin Films

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稀有金属材料与工程 2006年第A03期35卷 550-551页

作者： Yun ye Yadong Jiang Yong Wang Zhiming Wu Guangzhong Xie School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 610054 China

A new method for the production of nanoscaled polymeric multilayer films of ferroelectric PVDF is *** ultrathin multilayer films of poly diallyldimethylammonium chloride (PDDA) and polyvinylidene fluoride (PVDF) have been prepared on fuzed quartz substrate by the layer-by-layer self-assembly (LbL-SA) *** PDDA/PVDF multilayer films with the thickness of 30 nm to 150 nm have been characterized by quartz crystal microbalance (QCM) and infrared spectra (IR) The QCM reveals that the alternant ultrathin films of PVDF and PDDA are well order *** electric property of the ultrathin PDDA/PVDF multilayer films at room temperature is *** results show that property of ultrathin films differed from that of the thick films.

关键词： ultrathin films PVDF PDDA LbL-SA

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高胆固醇血样的红外吸收光谱研究

光谱学与光谱分析 2007年第6期27卷 1090-1092页

作者：姚红兵叶霞赵志敏江苏大学机械工程学院光学系江苏镇江212013 南京航空航天大学理学院江苏南京210016

红外光谱法及与其相关技术的应用研究,促进了光测技术的迅猛发展。文章针对血液的红外光谱分析这一重要课题,提出了血液的红外吸收光谱分析新技术,通过在一定的频谱范围内对正常血样与异常血液的红外吸收光谱进行实验测量和分析,可以判... 详细信息

红外光谱法及与其相关技术的应用研究,促进了光测技术的迅猛发展。文章针对血液的红外光谱分析这一重要课题,提出了血液的红外吸收光谱分析新技术,通过在一定的频谱范围内对正常血样与异常血液的红外吸收光谱进行实验测量和分析,可以判断血样是否异常,其实验和分析方法具有一定的先进性。文章中研究了正常血样和高胆固醇血样的红外吸收光谱之间的差别,并给出了人的正常血清与高胆固醇血清的红外吸收光谱以及分析结果,研究结果表明它们的吸收率、吸收峰位置以及吸收率之比之间的差别可以作为检验正常血样与异常血样的依据,从而为应用于疾病诊断方面提供了重要的参考。

关键词：高胆固醇血液红外吸收光谱

A Layout Method of Space-Based Pseudolite System Based on GDOP Geometry

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Chinese Journal of Electronics 2023年第5期32卷 1050-1058页

作者： YANG Xin WANG Feixue LIU Wenxiang XIAO Wei ye Xiaozhou National University of Defense Science and Technology

The pseudolite system can be used to provide positioning and timing service for users in a specific area. In order to provide better positioning and timing service, a good geometric configuration needs to be formed for the pseudolite system. For the problem of pseudolite system deployment, the average and mean square values of geometric dilution of precision(GDOP)are optimized in this paper for users in a target area. We proposed a space-based pseudolite deployment method based on GDOP geometry, starting from the minimum GDOP value for users in the central area. From the simulation results, it can be seen that, compared with the empirical method and the NSGA-II method, the method in this paper has the smallest average GDOP, a better robustness, and a higher positioning accuracy in the target area, through which a pseudolite deployment proposal can be quickly obtained.

关键词： Geometry Simulation Layout Robustness Timing Spatiotemporal phenomena Proposals

Preparation and performance analysis of a coking coal dust suppressant spray

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International Journal of Coal Science & Technology 2021年第5期8卷 1003-1014页

作者： Jiuhong Jiang Pengfei Wang ye Pei Ronghua Liu Liming Liu Yunchu He School of Resource Environment and Safety EngineeringHunan University of Science and TechnologyXiangtan 411201China Work Safety Key Lab On Prevention and Control of Gas and Roof Disasters for Southern Coal Mines Hunan University of Science and TechnologyXiangtan 411201China Hunan Jiujiu Environmental Protection Intelligent Co.Ltd Changsha 410000China

Coking coal dust is extremely hydrophobic;therefore,combination with droplets in the air is difficult and dust suppression is ***,a dust suppressant spray for coking coal dust was studied in order to improve of the combination of droplets and coking coal *** on monomer optimization and compounding analysis,two surfactant monomers,fatty alcohol ether sodium sulfate(AES)and sodium dodecyl benzene sulfonate(SDBS)were selected as the surfactant components of the dust *** surfactant monomers were combined with four inorganic salts and the reverse osmosis moisture absorption of each solution was *** combining the reverse osmosis moisture absorption values with the water retention experimental results,CaCl_(2)was identified as the optimal inorganic salt additive for the dust ***,the optimal concentration of each component was obtained using orthogonal experimental design i.e.,AES(0.03%),SDBS(0.05%),and CaCl_(2)(0.4%).The dust suppressant solution formulated using this method had a high moisture absorption capacity and excellent performance.

关键词： Coking coal Dust Spray Dust suppressant Surfactant Inorganic salt additive

Numerical modeling of the dynamic variation in multiphase CH_(4) during CO_(2) enhanced gas recovery from depleted shale reservoirs

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Frontiers of Earth Science 2021年第4期15卷 790-802页

作者： Lijun CHENG ye ZHANG Jun LIU Zhaohui LU Chunlin ZENG Peng ZHAO Key Laboratory of Shale Gas Exploration(Ministry of Natural Resources) Chongqing Institute of Geology and Mineral ResourcesChongqing 401120China Institute of New Energy and Low-Carbon Technology Sichuan UniversityChengdu 610065China College of Architecture and Environment Sichuan UniversityChengdu 610065China

Regarding CO_(2)enhanced shale gas recovery,this work focuses on changes in the multiphase(free/adsorbed)CH_(4)in the process of CO_(2)enhanced shale gas recovery,by utilizing a rigorous numerical model with real geological *** work studies nine injection well(IW)and CH_(4)production well(PW)combinations of CO_(2)to determine the influence of IW and PW locations on the dynamic interaction of multiphase CH_(4)during 10000 d of CO_(2)*** results indicate that the content of both the adsorbed CH_(4)and free CH_(4)is strongly variable before(and during)the CO_(2)-CH_(4)*** addition,during the simulation process,the proportion of the adsorbed CH_(4)among all extracted CH_(4)phases dynamically increases first and then tends to stabilize at 70%-80%.Moreover,the IW-PWs combinations signifi-cantly affect the outcomes of CO_(2)enhanced shale gas recovery-for both the proportion of adsorbed/free CH_(4)and the recovery efficiency.A longer IW-PW distance enables more adsorbed CH_(4)to be recovered but results in a lower efficiency of shale gas ***,a shorter IW-PWs distance helps recover CH_(4)via CO_(2)injection if the IW targets the bottom layer of the Wufeng-Longmaxi shale *** numerical work expands the knowl-edge of CO_(2)enhanced gas recovery from depleted shale reservoirs.

关键词： CO_(2)-CH_(4)displacement free gas Longmaxi shale CH_(4)desorption numerical simulation