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Supramolecular synthesis of coumarin derivatives catalyzed by a coordination-assembled cage in aqueous solution

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Science China Chemistry 2019年第6期62卷 713-718页

作者： Shao-Chuan Li Li-Xuan Cai Li-Peng Zhou Fang Guo Qing-Fu Sun State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences College of Chemistry Liaoning University

A self-assembled Pd_4L_2 cage is employed as a water-soluble molecular flask for the synthesis of functionalized coumarins from a series of salicylaldehyde derivatives and cyanoacetates/malononitrile. The catalytic reaction features mild aqueous conditions and broad substrate scope. Crystal structures of the host-guest complexes for two substrates and one analogous intermediate have been obtained, shedding light on the supramolecular reaction mechanism. Michaelis-Menten kinetic studies were performed in one typical case, revealing that the rate of product formation has been enhanced by over 23-fold in contrast to the background reaction without cage. Moreover, the same reaction catalyzed by a smaller Pd_6L_4 cage gives a mixture of products and much lower yields, suggesting that fine-tuning on the size and symmetry of the cages' cavity is crucial for their applications in supramolecular catalysis.

关键词： coordination-assembly cage encapsulation Knoevenagel condensation

Influence of the cage on the migration and distribution of lubricating oil inside a ball bearing

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Friction 2022年第7期10卷 1035-1045页

作者： He LIANG Yu ZHANG Wenzhong WANG School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

The migration and distribution of lubricant oil in a rolling bearing strongly affect the elastohydrodynamic lubrication performance between the balls and ***,oil re-lubrication is highly dependent on the bearing design,which is different from the ball-on-disc *** study directly observed the distribution of the lubricant film in a custom-made model-bearing rig,with an outer ring replaced by a glass ring to allow full optical *** influence of the cage type and surface properties were *** physical origin of the re-lubrication mechanism,including capillary flow and mechanical redistribution,was discussed.

关键词： ball bearings oil distribution lubrication cage

Automatic cage Building with Quadric Error Metrics

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Journal of Computer Science & Technology 2011年第3期26卷 538-547页

作者：邓正杰罗笑南苗晓萍 School of Information Science and Technology Sun Yat-Sen University National Engineering Research Center of Digital Life Research Institute of Sun Yat-Sen University in Shenzhen School of Software Sun Yat-Sen University

Modern computer graphics applications usually require high resolution object models for realistic rendering. However, it is expensive and difficult to deform such models in real time. In order to reduce the computational cost during deformations, a dense model is often manipulated through a simplified structure, called cage, which envelops the model. However, cages are usually built interactively by users, which is tedious and time-consuming. In this paper, we introduce a novel method that can build cages automatically for both 2D polygons and 3D triangular meshes. The method consists of two steps： 1） simplifying the input model with quadric error metrics and quadratic programming to build a coarse cage; 2） removing the self-intersections of the coarse cage with Delaunay partitions. With this new method, a user can build a cage to envelop an input model either entirely or partially with the approximate vertex number the user specifies. Experimental results show that, compared to other cage building methods with the same number of vertex, cages built by our method are more similar to the input models. Thus, the dense models can be manipulated with higher accuracy through our cages.

关键词： cage quadric error metrics mesh simplification self-intersection deformation

Triply-bridged Dicopper(Ⅰ)Complex of Bis(diphenylphosphino)acetylene with a Helical Coordination cage

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Chinese Journal of Structural Chemistry 2002年第6期21卷 605-608页

作者： HAN Lei ZHANG Li-Yi CHEN Zhong-Ning HONG Mao-Chun(State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, The Chinese Academy of Sciences, Fuzhou, Fujian 350002, China) State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China

Self-organization of copper (I) ion with bridging ligand bis(diphenylphosphino)-acetylene resulted in the isolation of a dinuclear copper ( I ) complex [Cu2(μ-Ph2PC≡ CPPh2)3(MeCN)2](ClO4)2·Et2O. Structural analysis indicated the existence of a helical coordination cage, in which two copper (I) atoms are bridged triply by the linear diphosphine Ph2PC≡CPPh2 with the CuACu separation of 6.231 A. The copper (I) atom is in an approximately tetrahedral environment with a NP3 coordination chromophore. The complex crystallizes in the triclinic, space group P 1 with a = 13.8456(2), b = 16.6010(1), c = 18.9215(3) A, α = 98.289(1), β = 91.232(1), γ = 106.496(1)°, V = 4117.60(9) A3, Z = 2, C86H82Cl2N2O9P6Cu2, Mr= 1659.37, Dc= 1.338 g/cm3, F(000) = 1708, μ = 0.754 mm-1, the final R = 0.0688 and wR = 0.1940 for 11692 reflections with I>2σ(I).

关键词： bis(diphenylphosphino)acetylene cage copper crystal structure helicity

The cage effect on assembly of cyclic-bis-(zinc porphyrin) with 5,15-dipyridylporphyrin

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Science China Chemistry 2009年第9期52卷 1353-1361,1519-1522页

作者： ZHOU ZaiChun ZHU YiZhou ZHENG JianYu State Key Laboratory and Institute of Elemento-organic Chemistry Nankai UniversityTianjin 300071China College of Chemical and Engineering Hunan University of Science and TechnologyXiangtan 411201China

An inclusion complex of cyclic bis(zinc porphyrin) 1 with 5,15-dipyridylporphyrin derivative 3 has been designed and constructed. The complex formation is induced by Zn-N coordination, and is robust (Kassoc ~ 106 L/mol) due to the presence of the cage effect of cyclic bis(zinc porphyrin). The cage-like complex as an entity is stable enough, and also convenient to achieve relative movement between the bis(zinc porphyrin) host and the dipyridylporphyrin guest connected by Zn-N coordination. The characteristics of these assemblies have been demonstrated by 1 H NMR, UV-vis, and fluorescence spectra. The results show its potential applications as a molecular gyroscope in molecular machines.

关键词： cage effect cyclic bis(zinc porphyrin) assembly template-directed synthesis

Experimental Study on the Hydrodynamic Characteristics of a Submersible Fish cage at Various Depths in Waves

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Journal of Ocean University of China 2019年第3期18卷 701-709页

作者： LIU Shengcong BI Chunwei YANG Hui HUANG Liuyi LIANG Zhenlin ZHAO Yunpeng Fisheries College Ocean University of China Qingdao 266003 China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China Marine College Shandong University Weihai 264209 China

Submersible fish cages can be submerged under the water to mitigate the negative effects that arise from severe sea conditions and improve the growing environment for the farmed fish. Thus they are increasingly applied in offshore aquaculture. To ensure both safety and economic efficiency of submersible fish cages, it is important to determine the optimum submergence depth. In this study, a series of physical model experiments were conducted to investigate the hydrodynamic performance of a submersible fish cage at various submergence depths(1/6, 1/4, 1/3, and 1/2 of the water depth as well as the floating condition for reference) with a model scale of 1:20. The results of the physical model experiment for the different depths were compared to analyze the effects of submergence depths on the mooring line tension and the movement of the floating collar. The results showed that the mooring line tension and the floating collar movement significantly attenuated with increasing submergence depth. However, the attenuation tendency became stable when the fish cage reached a certain depth. According to the results, 1/3 of water depth was determined as the optimal submergence depth of the fish cages. Deeper submergence depths showed no significant advantage from a perspective of the hydrodynamic characteristics of the fish cage. The determination of the optimum submergence depth is beneficial for the structural design and operation safety of submersible net cages.

关键词： submersible fish cage hydrodynamic characteristics submergence depth model experiment

The planimetric unfold method of fullerene cage structure

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Chinese Science Bulletin 2000年第20期45卷 1893-1896页

作者： YE Danian Al Desheng HE Wei XU Wendong Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Beijing Fine Ceramic Laboratory Institute of Nuclear Energy TechnologyTsinghua UniversityBeijing 102201China

Two kinds of planimetric diagrams, which consist of the boat form F6 and F5, the storm petrel form F6and F5, respectively, were proposed to express the geometric structure of fullerene cage in this study. There are two chief advantages using the diagrams: ( i) the spatial symmetrical characteristic of fullerene cage is not destroyed; (ii) the coordination forms of F5 and F6 in the structure can be clearly expressed. This work has laid the foundation for studying the structural geometry of fullerene cage and its quantum chemistry and property.

关键词： fullerene cage structural geometry boat form storm petrel form symmetry.

Sustainability level of the pearl lobster(Panulirus ornatus)aquaculture business using the systems of floating-net cage and fixed-net cage:A case study in South Sulawesi Province,Indonesia

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Aquaculture and Fisheries 2024年第5期9卷 851-859页

作者： Nimmi Zulbainarni Muhammad Hairul Haj Novindra School of Business Bogor Agricultural InstituteBogor16143Indonesia Tropical Marine Economics Study Program Bogor Agricultural InstituteBogor16680Indonesia Department of Resource Economics and Environment Bogor Agricultural InstituteBogor16680Indonesia

Marine aquaculture is currently the fastest-growing seafood industry globally,offering a potential solution to overfishing problems,while enhancing food security and income *** Sulawesi,a province in Indonesia,is rich in aquaculture resources,one of which is *** two commonly used aquaculture systems are the floating-net cage(KJA)and fixed-net cage(KJD).The growing market demand and rising lobster prices pose a threat to resource sustainability due to *** is issue have to be addressed to achieve sustainable fishery *** is the primary focus on global fishery *** to the United Nations,sustainable development encompasses three dimensions:the economy,social and ***,sustainable fishery,particularly aquaculture,relies on obtaining significant benefits while minimizing environmental ***,this study aimed to analyze the sustainability level of the pearl lobster(Panulirus ornatus)aquaculture in South Sulawesi,based on the provided background *** study included a sample of 62 *** sample selection involved the use of the stratified sampling method,with 51 farmers from(KJA)and 11 farmers from(KJD).The sustainability analysis,conducted through assessment of based farmers’perceptions,served as the analytical *** findings revealed that pearl lobster(Panulirus ornatus)aquaculture has a medium level of *** Integrated Multi Tropic Aquaculture(IMTA)and Regional Integrated Multi Tropic Aquaculture(RIMTA)techniques is a recommended sustainability level.

关键词： cage Sustainability Pearl Lobster South Sulawesi Province Indonesia

OUTCOME OF POSTEROLATERAL FUSION VERSUS CIRCUMFERENTIAL FUSION WITH cage FOR LUMBAR STENOSIS AND LOW DEGREE LUMBAR SPONDYLOLISTHESIS

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Chinese Medical Sciences Journal 2006年第1期21卷 41-47页

作者： Yi-peng Wang Qi Fei Gui-xing Qiu Hong Zhao Jian-guo Zhang Ye Tian Jin Lin Xi-sheng Weng Bin Yu Department of Orthopedic Surgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730

Objective To evaluate the outcome of two methods for stabilization and fusion: posterolateral fusion and circumferential fusion involving posterior lumbar interbody fusion for lumbar stenosis with Grades 1 and 2 lumbar *** From April 1998 to April 2003, 45 patients suffering from lumbar stenosis with low degree lumbar spondylolisthesis treated in our hospital were retrospectively reviewed and assigned to two *** them, 24 patients (group A) were treated with instrumented posterolateral fusion and 21 patients (group B) with instrumented circumferential *** two groups were compared for clinical and radiological *** All patients were followed up for 12 to 72 *** group A, results showed preoperative clinical symptoms disappeared completely in 12 of 24 patients, and pain relief was seen in 91.7% (22/24).Two cases suffered from residual ***-two cases obtained complete reduction of olisthy vertebral bodies, and anatomical reduction rate was 91.7%.No infection or neurological complication occurred in this *** group B, results showed preoperative clinical symptoms disappeared completely in 13 of 21 patients, and pain relief was seen in 90.5% (19/21).One case suffered from residual *** cases obtained complete reduction of the olisthy vertebral bodies, and anatomical reduction rate was 95.2%.Four cases of infection or neurological complication occurred in this *** groups indicated no significant difference in clinical outcomes and anatomical reduction rate during *** group A had better intraoperative circumstances and postoperative outcome than group B, while group B had better postoperative parameters in X-ray of Angle of Slipping and Disc Index than group *** The first choice of surgical method for lumbar stenosis with low degree lumbar spondylolisthesis is instrumented posterolateral *** when patients suffer from severe preoperative disc degeneration and l

关键词： lumbar vertebra lumbar stenosis spondylolisthesis transpedicle internal fixation cage