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1.
Recent progress in the research of radical anion ligands and their complexes with metals were summarized in this review. Radical anions were sorted into several types including iminosemiquinonate and iminoquinonate radical, nitroxide radical, heterocycle radical etc. Structural characteristics and properties of the corresponding complexes were introduced. The complexes exhibited novel properties and possibility for applications in organic magnetic materials and transition metal catalysis.  相似文献   
2.
设k是有限域.A是k上的满足一定有限性条件的本质小的遗传阿贝尔范畴.本文研究了有界复形范畴的modified Ringel—Hall 代数MH(A)中零微分复形乘积的结构常数,给出了它们与A的Ringel-Hall 代数H(A)的Hall数之间的关系.  相似文献   
3.
The picture of synthetic biology as a kind of engineering science has largely created the public understanding of this novel field, covering both its promises and risks. In this paper, we will argue that the actual situation is more nuanced and complex. Synthetic biology is a highly interdisciplinary field of research located at the interface of physics, chemistry, biology, and computational science. All of these fields provide concepts, metaphors, mathematical tools, and models, which are typically utilized by synthetic biologists by drawing analogies between the different fields of inquiry. We will study analogical reasoning in synthetic biology through the emergence of the functional meaning of noise, which marks an important shift in how engineering concepts are employed in this field. The notion of noise serves also to highlight the differences between the two branches of synthetic biology: the basic science-oriented branch and the engineering-oriented branch, which differ from each other in the way they draw analogies to various other fields of study. Moreover, we show that fixing the mapping between a source domain and the target domain seems not to be the goal of analogical reasoning in actual scientific practice.  相似文献   
4.
杨传明 《科学技术与工程》2015,15(7):186-190,194
日益增长的环境压力对复杂产品供应链碳足迹优化提出了更高的要求。为了降低优化过程动态性及不确定性,在综合评述产品拆卸建模分析研究方法的基础上,依据约束关系和装配结构,通过构建规则,设计多目标复杂产品碳足迹结构元拆卸混合图模型,确立模型约束关系矩阵,利用迭代分层思想设计驱动式递归聚类搜索算法,规划各层次碳足迹结构元模块。经液晶显示器实例证明,该规划方法可有效剖析复杂产品碳足迹结构基本元及模块单元。  相似文献   
5.
In order to describe collaborative decision-making process, the command and control model is put forward based on complex information relation integrtion and OODA. The characteristics of individual decision-making are analyzed, the complex information relation is considered as the cause of OODA difficulty to describe collaborative decision-making exactly. From the perspective of armament system of systems combat, the information, data, intelligence and knowledge is defined based on knowledge management and Shannon's entropy theory. The basic element is confirmed and the information flow way is analyzed which in the physical, information, cognitive and social domains. From the perspective of information, the armament system of systems complex networks model framework is put forward based on the idea of using OODA to guide armament system of systems complex networks model design. The data, information, intelligence and knowledge flow is analyzed and the describing meta-model is put forward. Using the reticular structure of OODA to describe collaborative decision-making idea is proposed, the command and control model is put forward based on the idea, the simulating tool ExtendSim is used for simulation analysis and results show that our work offer a reference for innovate command and control thory. ©, 2015, The Journal Agency of Complex Systems and Complexity Science. All right reserved.  相似文献   
6.
可视化是研究复杂网络的重要方法,目前2D平面可视化研究十分成熟,而3D可视化研究相对较少.为解决目前3D可视化布局结果不能真实展示复杂网络结构特征的问题,提出了一种两级力导引3D可视化算法.该算法基于复杂网络的特征分析,通过对网络聚类得到多个子网络及建立抽象网络,然后分两步依次对抽象网络和子网络进行力导引布局,从而得到最终布局.真实数据的实验分析表明,该算法的可视化布局结果能够真实展示复杂网络结构特征,同时具有较低的时间复杂度和较好美观度、清晰度.  相似文献   
7.
To better explore the universal robustness against cascading failures on complex networks, closely focusing on the load which is the most important physical quantity that can affect the spread of cascading failure, and dynamic process after a node fails, a cascading failure model with tunable parameters is proposed based on the local characteristic of node. With this model we study the cascading failure condition of ER and BA networks, and obtain the formula of phase transition point theoretically. The relationship between the robustness against cascading failures on complex networks and parameters in the model, including the topology parameters, the initial load coefficient, and the redistribution coefficient, is discussed numerically. In addition, theoretical results also are verified by the simulation results of the ER and BA networks. ©, 2015, The Journal Agency of Complex Systems and Complexity Science. All right reserved.  相似文献   
8.
岳展  史波珍 《科技信息》2013,(11):402-402
提出一种适用于复杂能源系统研究的半物理模拟方法,分析了单纯实验和单纯模拟研究的不足,而利用半物理模拟研究方法则更快捷,结果更为准确,预测的范围更为宽广。  相似文献   
9.
通过L分解求得L质数集合,于LQ上定义运算得LQ群;并提出具有正反双性的复元体集W,通过约消变换R获得W,在其上建立容消运算U,证明W与LQ群同构而称其为LQR群;最后阐述了它们中反元的实际意义与两群的作用.  相似文献   
10.
利用溶液法合成了Na4[Ti4O4(nta)4].12H2O配合物,同时对该配合物进行红外光谱和X-衍射表征,结果表明:该配合物为三斜晶系,空间群为P-1,a=9.8062(17),b=11.937(2),c=12.059(2),V=1200.8(4)3,Z=4.  相似文献   
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