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Synthesis,Structure and Electrochemistry of Triruthenium Cluster Complex [Ru_3(μ_3- O)(μ-CH_3CO_2)_6(py)_2(PPh_2py)](PF_6)·CH_2Cl_2
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作者 陈景林 张礼仪 陈忠宁 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第9期1022-1026,共5页
The reaction between [Ru3(3-O)(-CH3CO2)6(py)2(MeOH)](PF6) (py = pyri- dine) and diphenyl-2-pyridyl-phosphine (PPh2py) gave the triruthenium cluster complex [RuIII3(3-O)(-CH3CO2)6(py)2(PPh2py)](PF6)CH2Cl2 (C40H44Cl2F6N... The reaction between [Ru3(3-O)(-CH3CO2)6(py)2(MeOH)](PF6) (py = pyri- dine) and diphenyl-2-pyridyl-phosphine (PPh2py) gave the triruthenium cluster complex [RuIII3(3-O)(-CH3CO2)6(py)2(PPh2py)](PF6)CH2Cl2 (C40H44Cl2F6N34O13P2Ru3) which was characterized by elemental analysis, IR, UV-Vis and 31P NMR spectroscopy, and X-ray single- crystal diffraction. The structure is of monoclinic, space group P21/n with a = 16.3896(1), b = 16.8773(2), c = 19.1438(2) ? b = 95.888(1), V = 5267.47(9) ?, Mr = 1324.83, Dc = 1.671 g/cm3, F(000) = 2636, m = 1.092 mm-1 and Z = 4. The final refinement gave R = 0.0508 and wR = 0.1111 for 6987 observed reflections (I > 2s(I)). Three Ru(III) atoms bridged by m3-oxo donor form an approximately isosceles triangle. The complex shows three quasireversible one- electron processes at E1/2 = 1.22 +0.03 and 1.20 V vs. Ag/AgCl. 展开更多
关键词 合成 晶体结构 电化学 钌簇合物 嘧啶 联苯-2-吡啶磷化氢
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Study on cobalt-carbon and iron-sulfur mixed cluster complexes——Synthesis and conformational analysis of mixed cluster complexes [μ-p-CH_3C_6H_4C_2Co_2 (CO)_6 S](μ-RS)Fe_2(CO)_6
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作者 SONG Li-Cheng WANG Zhong-Xia WANG Ji-Tao 《Acta Chimica Sinica English Edition》 SCIE CAS CSCD 1989年第2期130-135,共1页
Through complexation reaction of arynyl Fe-S complexes A(μ-p-CH_3C_6H_4C≡CS)(μ- RS)Fe_2(CO)_6 with Co_2(CO)_6, eight mixed cluster complexes B[μ-p-CH_3C_6H_4C_2Co_2(CO)_6S](μ- RS)Fe_2(CO)_6 have been synthesized.... Through complexation reaction of arynyl Fe-S complexes A(μ-p-CH_3C_6H_4C≡CS)(μ- RS)Fe_2(CO)_6 with Co_2(CO)_6, eight mixed cluster complexes B[μ-p-CH_3C_6H_4C_2Co_2(CO)_6S](μ- RS)Fe_2(CO)_6 have been synthesized. Reactivity of the complexation reaction is approximately equi- valent to that of the reaction of diarylacetylene with Co_2(CO)_8. Conformational analysis has shown that R groups in complexes A are linked to sulfur atoms by a-and e-bond, whereas that in B only by art e-type of bond. 展开更多
关键词 CO Fe Study on cobalt-carbon and iron-sulfur mixed cluster complexes Synthesis and conformational analysis of mixed cluster complexes CO CH
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New Approach to Cluster Synchronization in Complex Dynamical Networks 被引量:3
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作者 LU Xin-Biao QIN Bu-Zhi LU Xin-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第3期485-489,共5页
在这篇论文,分布式的控制策略被建议让一个复杂动态网络完成簇同步,它意味着在一样的组的节点完成一样的同步状态,当在不同的组的节点完成不同同步状态时。簇同步状态的本地、全球的稳定性被分析。而且。
关键词 动态网络 群同步 节点同步 控制策略 分布式 状态
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Cluster exponential synchronization of a class of complex networks with hybrid coupling and time-varying delay 被引量:1
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作者 王军义 张化光 +1 位作者 王占山 梁洪晶 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期324-334,共11页
This paper deals with the cluster exponential synchronization of a class ot complex networks wlm nyorm coupm^g and time-varying delay. Through constructing an appropriate Lyapunov-Krasovskii functional and applying th... This paper deals with the cluster exponential synchronization of a class ot complex networks wlm nyorm coupm^g and time-varying delay. Through constructing an appropriate Lyapunov-Krasovskii functional and applying the theory of the Kronecker product of matrices and the linear matrix inequality (LMI) technique, several novel sufficient conditions for cluster exponential synchronization are obtained. These cluster exponential synchronization conditions adopt the bounds of both time delay and its derivative, which are less conservative. Finally, the numerical simulations are performed to show the effectiveness of the theoretical results. 展开更多
关键词 complex network cluster exponential synchronization linear matrix inequality time-varying de-lay
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Electron Spin Resonance(ESR)Spectroscopy of the Transition-metal Complexes and Clusters I.Systematic Investigations of Real-and Complex-Orbital Methods for Calculating the d-Orbital Energies of a Low-spin(S=1/2)nd^5(t_2~5,~2T_2)(n=3
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作者 ZHAO Kun (Fujian Institute of Research on the Structure of Matter, the Chinese Academy of Sciences, Fuzhou, Fujian, China 350002) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第2期61-65,共5页
On the basis of the first paper’s theoretical derivations and concrete instance calculations of the energies of the d orbitals for a low spin ( S =1/2) nd 5(t 2 5, 2T 2)(n =3, 4, 5) system, the ma... On the basis of the first paper’s theoretical derivations and concrete instance calculations of the energies of the d orbitals for a low spin ( S =1/2) nd 5(t 2 5, 2T 2)(n =3, 4, 5) system, the major results reported in this paper contain the following two respects: explicit relationships between the coefficients of the real and complex Kramers doublets have been derived by using two types of the expressions of the principal components of the g tensors in real and complex orbital representations obtained in the first paper; the use of these relationships of the real and complex orbital coefficients has carried out a series of mathematical demonstrations on the agreement of the real and complex orbital methods . 展开更多
关键词 ESR transition metal complexes and clusters low spin d 5 systems
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Cluster synchronization of uncertain complex networks with desynchronizing impulse 被引量:1
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作者 蔡国梁 姜胜芹 +1 位作者 蔡水明 田立新 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期109-116,共8页
Cluster synchronization of nonlinear uncertain complex networks with desynchronizing impulse is explored. First of all, a feedback controller is employed, based on the Lyapunov stability theorem and Lipschitz conditio... Cluster synchronization of nonlinear uncertain complex networks with desynchronizing impulse is explored. First of all, a feedback controller is employed, based on the Lyapunov stability theorem and Lipschitz condition, to guarantee that the uncertain complex networks with desynchronizing impulse synchronize with an object trajectory. Furthermore, a synchronizing impulse controller is presented, which is more efficiently and directly used to achieve the cluster synchronization. Finally, numerical examples are examined to show the effectiveness of the proposed methods. 展开更多
关键词 uncertain complex networks desynchronizing impulse cluster synchronization
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A study of TCM master Yan Zhenghua’s medication rule in prescriptions for digestive system diseases based on Apriori and complex system entropy cluster
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作者 Jiarui Wu Weixian Guo +4 位作者 Yan Tang Aiqing Han Bing Yang Dan Zhang Bing Zhang 《Journal of Traditional Chinese Medical Sciences》 2015年第4期241-247,共7页
Objective:To explore Yan Zhenghua’s drug selection rule for treating digestive system diseases using data mining.Methods:The 609 medical records of digestive system diseases treated by Yan Zhenghua were collected and... Objective:To explore Yan Zhenghua’s drug selection rule for treating digestive system diseases using data mining.Methods:The 609 medical records of digestive system diseases treated by Yan Zhenghua were collected and the herbs in these recipes were examined using a data mining technique.The correlativity between herb pairs and association rules was studied using an Apriori algorithm and the correlativity among multi-herbs was studied using a complex system entropy cluster technique.Results:Yan Zhenghua’s treatment of digestive system diseases featured 15 herbs prescribed at least 159 times each,22 herb pairs prescribed at least 155 times each,and eight frequently used herb core combinations.A confidence greater than 0.91 and a support level greater than 20%were achieved using the modified mutual information method.Conclusion:The data mining results conformed to findings from clinical practice.The data mining method is a valuable technique with which to study the experience of famous,elderly traditional Chinese medicine physicians. 展开更多
关键词 Yan Zhenghua complex system entropy cluster Digestive system diseases Medication rule
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Molecular Design and Electronic Structure of Polynuclear Rare Earth Complexes and Clusters
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作者 徐光宪 高松 +2 位作者 黎乐民 吴瑾光 黄春辉 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第4期241-247,共7页
Studies on the electronic structure,molecular design,syntheses of some novel series of tetranuclear rare earth complexes in our laboratory have been reviewed.Spin-unrestricted localized INDO method was used to calcula... Studies on the electronic structure,molecular design,syntheses of some novel series of tetranuclear rare earth complexes in our laboratory have been reviewed.Spin-unrestricted localized INDO method was used to calculate the electronic structure and the chemical bonding in the typical rare earth cluster Sc[Sc_6Cl_(12)Co]was discussed. 展开更多
关键词 Molecular design Electronic structure Rare earths Polynuclear complexes clusterS INDO
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A NOVEL REACTION BETWEEN [μ-PhC(O)S]-(μ-RS)Fe_2(CO)_6 AND (μ-R^1S)(μ-XMgS)Fe_2(CO)_6——THE SYNTHESIS, CHARACTERIZATION AND FORMATION MECHANISM OF TWIN CLUSTER COMPLEXES [(μ-RS)Fe_2(CO)_6](μ_4-S)[(μ-R^1S)Fe_2(CO)_6]
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作者 宋礼成 胡青眉 +1 位作者 贾国锋 王劲扬 《Science China Chemistry》 SCIE EI CAS 1992年第1期1-9,共9页
The reaction of (μ-RS)(μ-XMgS)Fe<sub>2</sub>(CO)<sub>6</sub> with PhC(O)Cl gave four new benzoyl complexes [μ-PhC(O)S](μ-RS)Fe<sub>2</sub>(CO)<sub>6</sub&... The reaction of (μ-RS)(μ-XMgS)Fe<sub>2</sub>(CO)<sub>6</sub> with PhC(O)Cl gave four new benzoyl complexes [μ-PhC(O)S](μ-RS)Fe<sub>2</sub>(CO)<sub>6</sub>(R=Me, Et, n-Bu, CH<sub>2</sub>=CHCH<sub>2</sub>), which further reacted with (μ-R<sup>1</sup>S)(μ-XMgS)Fe<sub>2</sub>(CO)<sub>6</sub> to afford eight new twin cluster complexes with the general formula of [(μ-RS)Fe<sub>2</sub>(CO)<sub>6</sub>](μ<sub>4</sub>-S)[(μ-R<sup>1</sup>S)Fe<sub>2</sub>(CO)<sub>6</sub>]. The single crystal X-ray analysis for one of these complexes (R=n-Bu, R<sup>1</sup>=Ph) showed that it consists of two different moieties PhSFe<sub>2</sub>(CO)<sub>6</sub> and n-BuSFe<sub>2</sub>(CO)<sub>6</sub> joined together through the spiran type of μ<sub>4</sub>-S., The complex belongs to space group P-1; cell parameters are a=9.028(3), b=10.386(1), c=16.723 (5); α=87.70(2)°,β=75.67(2)°, r=82.26(2)°; z=2, Dx=1.743 g/cm<sup>3</sup>. Final deviation factor R=0.031. 展开更多
关键词 TWIN cluster Fe-S complex SYNTHESIS REACTION single crystal structure mechanism.
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Cluster projective synchronization of complex networks with nonidentical dynamical nodes
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作者 姚洪兴 王树国 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期132-138,共7页
We investigate a new cluster projective synchronization (CPS) scheme in time-varying delay coupled complex dynamical networks with nonidentical nodes. Based on the community structure of the networks, the controller... We investigate a new cluster projective synchronization (CPS) scheme in time-varying delay coupled complex dynamical networks with nonidentical nodes. Based on the community structure of the networks, the controllers are designed differently for the nodes in one community, which have direct connections to the nodes in the other communities and the nodes without direct connections to the nodes in the other communities. Some sufficient criteria are derived to ensure the nodes in the same group projectively synchronize and there is also projective synchronization between nodes in different groups. Particularly, the weight configuration matrix is not assumed to be symmetric or irreducible. The numerical simulations are performed to verify the effectiveness of the theoretical results. 展开更多
关键词 cluster projective synchronization complex network time-varying delay adaptive con-troller
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Novel Properties of Supramolecular Complexes Formed by Pairing Cationic Porphyrin and Anionic Metal-Oxo Cluster
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作者 Shu Qing LIU Ji Qing XU Hao Ran SUN Department of Chemistry, Jilin University, Changchun 130023 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第9期831-834,共4页
MTBPyP (meso-tetrakis(4-N-benzylpyridyl)porphyrin, M=H-2, Zn) bearing positive charge has been shown to associate with SiW12O404- in water solution. The spectral evolution and Job's plots analyses reveal that the ... MTBPyP (meso-tetrakis(4-N-benzylpyridyl)porphyrin, M=H-2, Zn) bearing positive charge has been shown to associate with SiW12O404- in water solution. The spectral evolution and Job's plots analyses reveal that the relatively stable aggregates contain equal numbers of MTBPyP4(+) and SiW12O404-. 展开更多
关键词 cationic porphyrin anionic metal-ore cluster ion pair supramolecular complex
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Hierarchical Modeling by Recursive Unsupervised Spectral Clustering and Network Extended Importance Measures to Analyze the Reliability Characteristics of Complex Network Systems 被引量:1
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作者 Yiping Fang Enrico Zio 《American Journal of Operations Research》 2013年第1期101-112,共12页
The complexity of large-scale network systems made of a large number of nonlinearly interconnected components is a restrictive facet for their modeling and analysis. In this paper, we propose a framework of hierarchic... The complexity of large-scale network systems made of a large number of nonlinearly interconnected components is a restrictive facet for their modeling and analysis. In this paper, we propose a framework of hierarchical modeling of a complex network system, based on a recursive unsupervised spectral clustering method. The hierarchical model serves the purpose of facilitating the management of complexity in the analysis of real-world critical infrastructures. We exemplify this by referring to the reliability analysis of the 380 kV Italian Power Transmission Network (IPTN). In this work of analysis, the classical component Importance Measures (IMs) of reliability theory have been extended to render them compatible and applicable to a complex distributed network system. By utilizing these extended IMs, the reliability properties of the IPTN system can be evaluated in the framework of the hierarchical system model, with the aim of providing risk managers with information on the risk/safety significance of system structures and components. 展开更多
关键词 complex NETWORK System Hierarchical Modeling Spectral clustering EXTENDED IMPORTANCE Measure
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Coarse-Graining Method Based on Hierarchical Clustering on Complex Networks
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作者 Lin Liao Zhen Jia Yang Deng 《Communications and Network》 2019年第1期21-34,共14页
With the rapid development of big data, the scale of realistic networks is increasing continually. In order to reduce the network scale, some coarse-graining methods are proposed to transform large-scale networks into... With the rapid development of big data, the scale of realistic networks is increasing continually. In order to reduce the network scale, some coarse-graining methods are proposed to transform large-scale networks into mesoscale networks. In this paper, a new coarse-graining method based on hierarchical clustering (HCCG) on complex networks is proposed. The network nodes are grouped by using the hierarchical clustering method, then updating the weights of edges between clusters extract the coarse-grained networks. A large number of simulation experiments on several typical complex networks show that the HCCG method can effectively reduce the network scale, meanwhile maintaining the synchronizability of the original network well. Furthermore, this method is more suitable for these networks with obvious clustering structure, and we can choose freely the size of the coarse-grained networks in the proposed method. 展开更多
关键词 complex Network SYNCHRONIZABILITY COARSE-GRAINING METHOD HIERARCHICAL clusterING
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中国省会航空节点城市复杂时空系统协调度变化及空间特征分析
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作者 韩瑞玲 李宗哲 +2 位作者 冉心月 郭晓阳 杜晓辉 《地理科学》 CSCD 北大核心 2024年第1期59-70,共12页
航空运输业提升了城市系统的吸引力并激发新的交通需求,引导城市经济和空间结构快速演进。本文构建了包含经济、规模、外贸、科技、社会、环境、航空等要素在内的城市复杂时空系统指标体系,对中国省会航空节点城市及其构成的7个空管区... 航空运输业提升了城市系统的吸引力并激发新的交通需求,引导城市经济和空间结构快速演进。本文构建了包含经济、规模、外贸、科技、社会、环境、航空等要素在内的城市复杂时空系统指标体系,对中国省会航空节点城市及其构成的7个空管区的复杂时空系统发展的协调程度变化情况及时空聚类特征、空间溢出效应进行了分析。研究发现:2001—2019年,中国31个省会(首府、直辖市)航空节点城市在复杂时空系统发展过程中呈现了或分散、或集中的趋势特征,南方城市在研究末期的协调程度表现更好。7个空管区中,华北区协调度最高,新疆区、西北区、华东区、中南区的协调度水平发展增速较快,航空系统的平均协调度最高。各航空节点城市复杂时空系统协调度的时空聚类模式存在空间分异特征与聚类特征,航空系统在空管区的聚类优势最为突出,经济系统在空管区聚类辐射范围最大。航空、规模、科技与环境系统均表现了正向直接空间溢出效应,经济与科技系统表现了正向间接空间溢出效应。通过全面分析航空节点城市及空管区的复杂时空系统协调度变化,精准判定了航空节点城市多指标系统在区域发展过程中的影响程度及时空分布异质性,对拓展航空地理研究及促进航空节点城市高质量综合发展提供理论依据。 展开更多
关键词 航空节点城市 复杂时空系统 协调度 空管区聚类优势
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成渝机场群航线网络有向加权结构特征分析
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作者 程擎 白宇 +1 位作者 王亚哲 夏沁琳 《舰船电子工程》 2024年第4期104-110,共7页
成渝机场群是成渝地区双城经济圈建设的重大战略部署,为探索成渝机场群航线网络拓扑结构的复杂性,运用复杂网络理论构建有向加权航线网络模型,计算其航线网络基本统计指标、中心性指标以及网络效率并对其网络结构进行分析研究。结果表... 成渝机场群是成渝地区双城经济圈建设的重大战略部署,为探索成渝机场群航线网络拓扑结构的复杂性,运用复杂网络理论构建有向加权航线网络模型,计算其航线网络基本统计指标、中心性指标以及网络效率并对其网络结构进行分析研究。结果表明成渝机场群具有明显的小世界特性;天府与江北机场为机场群实际枢纽,但航线同质化竞争严重,航点重合度较高问题较为严重;各支线机场虽具备一定缓解枢纽压力但层次结构不清晰及发展滞缓;枢纽与非枢纽间联系不紧密、中心化程度低;达州与巫山机场可分别作为枢纽的紧密次枢纽机场进行发展;当网络收到攻击时网络效率低下,并提出参考建议。 展开更多
关键词 复杂网络 航线网络 中心性 成渝机场群
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基于Apriori算法与因子分析探讨帕金森病的中医药用药规律
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作者 刘煜 李鸣 +1 位作者 杨琼 杨春娣 《中西医结合心脑血管病杂志》 2024年第3期445-451,共7页
目的:运用复杂网络分析中医药治疗帕金森病用药的相互关系。方法:收集中医药方剂治疗帕金森病的相关文献,建立中药数据库,采用SPSS软件进行复杂网络分析探讨各药物相互关系。结果:中医药治疗帕金森病高频用药排名居前6位为白芍、熟地黄... 目的:运用复杂网络分析中医药治疗帕金森病用药的相互关系。方法:收集中医药方剂治疗帕金森病的相关文献,建立中药数据库,采用SPSS软件进行复杂网络分析探讨各药物相互关系。结果:中医药治疗帕金森病高频用药排名居前6位为白芍、熟地黄、当归、甘草、钩藤、天麻,并对其进行聚类分析及因子分析,得出7类组方和11类公因子。运用关联规则分析得出中药用药以白芍-熟地黄核心药对进行加减。结论:中医药治疗帕金森病常以滋阴养血为主要原则,平肝息风、化痰散结、开窍醒神等为常用治疗方法,其核心药对为白芍-熟地黄。 展开更多
关键词 帕金森病 震颤麻痹 聚类分析 关联分析 复杂网络 用药规律
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八核铁簇化合物的制备、表征及其对高氯酸铵的热分解催化
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作者 黄琪 刘丽 +1 位作者 金波 彭汝芳 《含能材料》 EI CAS CSCD 北大核心 2024年第5期484-491,共8页
以5,5′-{[3,3′-双(1,2,4-噁二唑)]-5,5′-基}-双(1-羟基四唑)为配体,通过溶剂热法制备了一种新型含能铁簇化合物[Fe_(2)Ⅲ(μ2-CH_(3)O)(μ_(3)-OH)(μ_(2)-O)(BODTO^(2-))(H_(2)O)]4(1),并对其进行了单晶X-射线衍射、差示扫描量热和... 以5,5′-{[3,3′-双(1,2,4-噁二唑)]-5,5′-基}-双(1-羟基四唑)为配体,通过溶剂热法制备了一种新型含能铁簇化合物[Fe_(2)Ⅲ(μ2-CH_(3)O)(μ_(3)-OH)(μ_(2)-O)(BODTO^(2-))(H_(2)O)]4(1),并对其进行了单晶X-射线衍射、差示扫描量热和热重分析等表征,分析了其结构和热稳定性,同时通过差热分析仪研究了化合物1对高氯酸铵(AP)热分解的催化性能。测试结果表明,化合物1为立方晶系I-43d空间群,密度为1.506 g·cm^(-3);晶体结构中Fe^(3+)与Fe^(3+)通过氧原子桥联,形成笼状结构;热分解峰值温度为513.9,617.6 K和669.4 K;爆速为6.94 km·s^(-1),爆压为19.09 GPa;撞击感度为15 J,摩擦感度为360 N。当添加质量分数为10%的化合物1时,AP的高温分解温度降低65 K,活化能降低82.2 kJ·mol^(-1),证实该铁簇化合物对AP的热分解具有较好的催化活性,具有应用于含能燃烧催化剂的潜质。 展开更多
关键词 含能配合物 铁簇 高氯酸铵 热分解 热催化
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基于网约车数据的级联城市区域分析框架研究
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作者 于娜 李小楠 白燕娜 《河北师范大学学报(自然科学版)》 CAS 2024年第1期29-35,共7页
针对城市区域的复杂性和多变性,提出了一个级联城市区域分析框架(cascaded urban area analysis framework,CUAAF),用来对城市区域进行时空聚类分析.首先,将城市区域划分为多个地理栅格.其次,采用新的区域时空行为指标(areabehaviorinde... 针对城市区域的复杂性和多变性,提出了一个级联城市区域分析框架(cascaded urban area analysis framework,CUAAF),用来对城市区域进行时空聚类分析.首先,将城市区域划分为多个地理栅格.其次,采用新的区域时空行为指标(areabehaviorindex,ABI)评估任意2个栅格之间的相关性.接着,用Louvain算法对相应的栅格网络进行分析,得到聚类区域.在得到聚类区域后,可再次将该区域输入CUAAF框架,进行级联分析,得到更多分层信息.级联实验可以采用多种指标分析城市区域,从不同层次了解城市区域,获得更详细的城市区域信息.最后,分别用周中周末的数据做了对比实验,结果显示本文方法具有稳健性和数据敏感性. 展开更多
关键词 城市区域聚类 级联框架 复杂网络 Louvain算法
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基于生态系统服务功能价值簇的复合型产业模式设计——以河北省阜平县为例
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作者 耿傲淼 张贵军 +1 位作者 徐磊 张蓬涛 《水土保持研究》 CSCD 北大核心 2024年第1期417-426,439,共11页
[目的]基于土地利用多功能特性构建复合型产业模式,为提高山区县的土地利用效率,推进区域生态与经济的高质量发展提供方法和参考。[方法]以太行山中段的阜平县为例,选取水源供给、保持土壤等9类生态系统服务功能作为评判阜平县土地多种... [目的]基于土地利用多功能特性构建复合型产业模式,为提高山区县的土地利用效率,推进区域生态与经济的高质量发展提供方法和参考。[方法]以太行山中段的阜平县为例,选取水源供给、保持土壤等9类生态系统服务功能作为评判阜平县土地多种功能空间集聚特征的依据,通过空间聚类分析得到不同的功能价值簇,并调整形成生态系统服务主导功能价值分区;在此基础上,叠加土地利用现状、地形地貌和现有产业发展布局,构建复合型产业发展模式。[结果](1)将研究区按生态系统服务功能价值的空间集聚特征分为6种功能价值簇;(2)调整各簇边界,形成维持生物多样性+提供美学景观+保持土壤区、提供美学景观+水源供给+原材料生产区等6类生态系统服务主导功能价值区;(3)在生态系统服务主导功能价值区的基础上,设计出“旅游业+文化产业”“智慧农业+旅游业”等7种复合型产业发展模式,可为实现阜平县乡村振兴与高质量发展提供新的驱动力。[结论]复合型产业模式的设计能够实现生态保护与经济发展的双驱并进,可为解决山区县生态保护与经济发展的矛盾问题提供案例参考。 展开更多
关键词 土地利用多功能 生态系统服务功能价值簇 复合型产业 聚类分析 阜平县
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基于高斯混合模型的分布因子聚类方法
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作者 朱映秋 黄丹阳 张波 《统计研究》 北大核心 2024年第6期147-160,共14页
随着信息技术的发展,人类社会产生的数据规模越来越庞大、形式越来越复杂,对聚类分析形成了巨大挑战。在越来越多的应用场景中,观测数据具有相互关联、层次嵌套的结构,使传统聚类方法难以直接适用。通常的解决方案是采用特征工程方法将... 随着信息技术的发展,人类社会产生的数据规模越来越庞大、形式越来越复杂,对聚类分析形成了巨大挑战。在越来越多的应用场景中,观测数据具有相互关联、层次嵌套的结构,使传统聚类方法难以直接适用。通常的解决方案是采用特征工程方法将观测信息压缩为低维特征向量进行聚类,但这将带来不可避免的信息损失。为充分利用观测数据,本文以分布函数表示聚类对象,大幅降低信息损失,进而提出基于高斯混合模型的分布因子模型。该模型将聚类对象的观测数据分解为两部分,一是以高斯成分表示的公共因子,反映数据中具有共性的典型模式;二是载荷矩阵,矩阵中每个载荷向量反映个体的异质性特征。估计得到载荷向量后即可对不同个体实现聚类划分。本文提出的方法具有优良的统计学效率,能够证明在一定假设条件下聚类误差率能够随着观测个体数目的发散而趋近于0。基于模拟数据和股票收益、大气污染实际数据的实验表明,该方法能够区分具有不同特征模式的个体,解决多维数据的分布函数聚类问题,并为金融风险管理、空气质量的差异化治理等现实问题提供决策支持。 展开更多
关键词 聚类 分布函数 高斯混合模型 复杂数据
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