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Numerical Analysis of the Structure of High-Strength Double-Layer Steel Plate Concrete Shaft by Drilling Method of Water-Bearing Weak Rock Formation
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作者 Touogam Touolak Benedicte 《Open Journal of Civil Engineering》 2022年第2期189-207,共19页
In order to ensure the safety of coal mine shaft construction, a double-layer steel plate concrete composite shaft wall structure was proposed. However, fewer studies were conducted on this structure, which made engin... In order to ensure the safety of coal mine shaft construction, a double-layer steel plate concrete composite shaft wall structure was proposed. However, fewer studies were conducted on this structure, which made engineers too confused to fully recognize its feasibility of this structure. Hence, based on the previous experimental research on the Taohutu mine construction project in  Ordos in Inner Mongolia, this research paper aims to provide a widely deep numerical analysis by the usage of the finite element software, in fact, to establish the corresponding numerical analysis model and make a comparison with the experimental data to get the rationality of the verified model. The influence of the composite characteristics of the steel plate and concrete on the ultimate bearing capacity and stress field of the shaft wall structure is studied here through the method of multi-factor analysis. Also, the optimal design scheme of the double-layer steel plate and concrete composite shaft wall structure is proposed in this research paper. 展开更多
关键词 Finite Element Method double-layer Steel Plate Shaft Wall structure Taohutu Mine Construction
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THE DOUBLE-LAYER STRUCTURE OF THE HADLEY CIRCULATION AND ITS INTERDECADAL EVOLUTION CHARACTERISTICS 被引量:1
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作者 CHENG Jian-bo HU Shu-juan CHOU Ji-fan 《Journal of Tropical Meteorology》 SCIE 2018年第2期220-231,共12页
Based on the three-pattern decomposition of global atmospheric circulation(TPDGAC), this study investigates the double-layer structure of the Hadley circulation(HC) and its interdecadal evolution characteristics by us... Based on the three-pattern decomposition of global atmospheric circulation(TPDGAC), this study investigates the double-layer structure of the Hadley circulation(HC) and its interdecadal evolution characteristics by using monthly horizontal wind field from NCEP/NCAR reanalysis data from 1948—2011. The following major conclusions are drawn: First, the double-layer structure of the HC is an objective fact, and it constantly exists in April,May, June, October and November in the Southern Hemisphere. Second, the double-layer structure is more obvious in the Southern than in the Northern Hemisphere. Since the double-layer structure is sloped in the vertical direction, it should be taken into consideration when analyzing the variations of the strength and location of the center of the HC.Third, the strength of the double-layer structure of the HC in the Southern Hemisphere consistently exhibits decadal variations with a strong, weak and strong pattern in all five months(April, May, June, October, and November), with cycles of 20-30 a and 40-60 a. Fourth, the center of the HC(mean position of the double-layer structure) in the Southern Hemisphere consistently and remarkably shifts southward in all the five months. The net poleward shifts over the 64 years are 5.18°, 2.11°, 2.50°, 1.79° and 5.76° for the five respective months, with a mean shift of 3.47°. 展开更多
关键词 three-pattern decomposition of global atmospheric circulation Hadley circulation double-layer structure decadal variations
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Performance and Application of Double-layered Microcapsule Corrosion Inhibitors
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作者 余海燕 WANG Yingxiang +2 位作者 WANG Ruizhi HU Lintong WANG Tianlei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期845-853,共9页
Double-layered microcapsule corrosion inhibitors were developed by sodium monofluorophosphate as the core material,polymethyl methacrylate as the inner wall material,and polyvinyl alcohol as the outer wall material co... Double-layered microcapsule corrosion inhibitors were developed by sodium monofluorophosphate as the core material,polymethyl methacrylate as the inner wall material,and polyvinyl alcohol as the outer wall material combining the solvent evaporation method and spray drying method.The protection by the outer capsule wall was used to prolong the service life of the corrosion inhibitor.The dispersion,encapsulation,thermal stability of microcapsules,and the degradation rate of capsule wall in concrete pore solution were analyzed by ultra-deep field microscopy,scanning electron microscopy,thermal analyzer,and sodium ion release rate analysis.The microcapsules were incorporated into mortar samples containing steel reinforcement,and the effects of double-layered microcapsule corrosion inhibitors on the performance of the cement matrix and the actual corrosion-inhibiting effect were analyzed.The experimental results show that the double-layered microcapsules have a moderate particle size and uniform distribution,and the capsules were completely wrapped.The microcapsules as a whole have good thermal stability below 230 ℃.The monolayer membrane structure microcapsules completely broke within 1 day in the simulated concrete pore solution,and the double-layer membrane structure prolonged the service life of the microcapsules to 80 days in the simulated concrete pore solution before the core material was completely released.The mortar samples containing steel reinforcement incorporated with the double-layered microcapsule corrosion inhibitors still maintained a higher corrosion potential than the monolayer microcapsule corrosion inhibitors control group at 60 days.The incorporation of double-layered microcapsules into the cement matrix has no significant adverse effect on the setting time and early strength. 展开更多
关键词 corrosion inhibitors MICROCAPSULE double-layer structure potentiodynamic polarization curve
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Nonlinear mechanics of a ring structure subjected to multi-pairs of evenly distributed equal radial forces 被引量:1
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作者 Q. Chen F. Sun +2 位作者 Z. Y. Li L. Taxis N. Pugno 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第5期942-953,共12页
Combining the elastica theory, finite element (FE) analysis, and a geometrical topological experiment, we studied the mechanical behavior of a ring subjected to multi-pairs of evenly distributed equal radial forces by... Combining the elastica theory, finite element (FE) analysis, and a geometrical topological experiment, we studied the mechanical behavior of a ring subjected to multi-pairs of evenly distributed equal radial forces by looking at its seven distinct states. The results showed that the theoretical predictions of the ring deformation and strain energy matched the FE results very well, and that the ring deformations were comparable to the topological experiment. Moreover, no matter whether the ring was compressed or tensioned by N-pairs of forces, the ring always tended to be regular polygons with 2N sides as the force increased, and a proper compressive force deformed the ring into exquisite flower-like patterns. The present study solves a basic mechanical problem of a ring subjected to lateral forces, which can be useful for studying the relevant mechanical behavior of ring structures from the nano- to the macro-scale. 展开更多
关键词 ring structures Mechanical properties SHAPE Strain energy
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Effects of C-terminal amidation and heptapeptide ring on the biological activities and advanced structure of amurin-9KY, a novel antimicrobial peptide identified from the brown frog, Rana kunyuensis 被引量:1
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作者 Fen Zhang Zhi-Lai Guo +3 位作者 Yan Chen Li Li Hai-Ning Yu Yi-Peng Wang 《Zoological Research》 SCIE CAS CSCD 2019年第3期198-204,共7页
Rana kunyuensis is a species of brown frog that lives exclusively on Kunyu Mountain,Yantai,China.In the current study,a 279-bp cDNA sequence encoding a novel antimicrobial peptide (AMP),designated as amurin-9KY,was cl... Rana kunyuensis is a species of brown frog that lives exclusively on Kunyu Mountain,Yantai,China.In the current study,a 279-bp cDNA sequence encoding a novel antimicrobial peptide (AMP),designated as amurin-9KY,was cloned from synthesized double-strand skin cDNA of R.kunyuensis.The amurin-9KY precursor was composed of 62 amino acid (aa) residues,whereas the mature peptide was composed of 14 aa and contained two cysteines forming a C-terminal heptapeptide ring (Rana box domain) and an amidated C-terminus.These structural characters represent a novel amphibian AMP family.Although amurin-9KY exhibited high similarity to the already identified amurin-9AM from R.amurensis,little is known about the structures and activities of amurin-9 family AMPs so far.Therefore,amurin-9KY and its three derivatives (amurin-9KY1-3) were designed and synthesized.The structures and activities were examined to evaluate the influence of C-terminal amidation and the heptapeptide ring on the activities and structure of amurin-9KY..Results indicated that C-terminal amidation was essential for antimicrobial activity,whereas both C-terminal amidation and the heptapeptide ring played roles in the low hemolytic activity.Circular dichroism (CD) spectra showed that the four peptides adopted an α-helical conformation in THF/H2O (v/v 1∶1) solution,but a random coil in aqueous solution.Elimination of the C-terminal heptapeptide ring generated two free cysteine residues with unpaired thiol groups,which greatly increased the concentration-dependent anti-oxidant activity.Scanning electron microscopy (SEM) was also performed to determine the possible bactericidal mechanisms. 展开更多
关键词 Antimicrobial peptides RANA kunyuensis' Amurin-9KY Heptapeptide ring C-TERMINAL AMIDATION structure activity relati on ship
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From Highly Structured E-Infinity Rings and Transfinite Maximally Symmetric Manifolds to the Dark Energy Density of the Cosmos 被引量:2
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作者 Mohamed S. El Naschie 《Advances in Pure Mathematics》 2014年第12期641-648,共8页
Starting from well established results in pure mathematics, mainly transfinite set theory, E-infinity algebra over operads, fuzzy manifolds and fuzzy Lie symmetry groups, we construct an exact Weyl scaling for the hig... Starting from well established results in pure mathematics, mainly transfinite set theory, E-infinity algebra over operads, fuzzy manifolds and fuzzy Lie symmetry groups, we construct an exact Weyl scaling for the highly structured E-infinity rings corresponding to E-infinity theory of high energy physics. The final result is an exact expression for the energy density of the cosmos which agrees with previous analysis as well as accurate cosmological measurements and observations, such as COBE, WMAP and Planck. The paper is partially intended as a vivid demonstration of the power of pure mathematics in physics and cosmology. 展开更多
关键词 HIGHLY structureD ringS E-INFINITY Loop Spaces High ENERGY Physics Dark ENERGY Einstein Relativity Fractal-Cantorian Spacetime Nonlinear Dynamics Quantum Chaos
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Two phenomena: Honji instability, and ringing of offshore structures 被引量:1
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作者 J. Grue 《Theoretical & Applied Mechanics Letters》 CAS 2011年第6期1-6,共6页
Honji instability and ringing of offshore structrures are two different phenomena. Honji instability occurs at a circular cylinder in transverse periodic finite motion in a water tank. It is superposed on the streamin... Honji instability and ringing of offshore structrures are two different phenomena. Honji instability occurs at a circular cylinder in transverse periodic finite motion in a water tank. It is superposed on the streaming flow induced by the cylinder’s boundary layer. Its oscillation period is half of the period of the cylinder oscillation. Finite volume calculations of the filtered Navier-Stokes equations visualize the three-dimensional instability, where fluid particles transported by the circumferencial roll pairs exhibit a periodic mushroom-like pattern. Force is the same with and without the Honji instability. The large eddy simulation calculations for high Reynolds number support a drag coefficient in accordance with the Stokes-Wang solution below separation and conform with experimental measurements of the damping force on a harmonically oscillating cylinder. Ringing of offshore structures are vibrations which appear at natural frequencies and concern fatigue. It is generated by a higher harmonic force oscillating with frequency being 3-4 times the fundamental wave frequency. Together with a strong inertia load in phase with the incoming wave’s acceleration, a secondary load cycle appears in strong seas when the wave crest leaves the structure; this occurs about 1/4 wave period after the main force peak, it starts when the wave crest is about one cylinder radius behind the cylinder, lasts for about 15-20 percent of the wave period and has a magnitude up to 11 % of the peak-to-peak total force. It is a gravity effect and appears in strong irregular seas when kA > 0.18 and um/√gD > 0.4 (k wavenumber, A amplitude, um maximal wave induced velocity, g acceleration of gravity, D cylinder diameter). 展开更多
关键词 Honji instability Honji rolls drag coefficient ringING secondary load cycle offshore structures
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Synthesis, Structure and Properties of Two Photochromic Compounds Containing A Pyrazolone-ring 被引量:1
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作者 TANG Xincun JIA Dianzeng +2 位作者 ZHANG Xiaogang XIA Xi ZHOU Zhongyuan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2000年第2期116-121,共6页
Two photochromic compounds with the pyrazolonering as the photochromic functional structure, 2(1phenyl3methyl4benzoformylpyrazolone5)thiosemicarbazone(PMBPTSC) and 2(1phenyl3methyl4benzoformylpyrazolone5)smethylthiose... Two photochromic compounds with the pyrazolonering as the photochromic functional structure, 2(1phenyl3methyl4benzoformylpyrazolone5)thiosemicarbazone(PMBPTSC) and 2(1phenyl3methyl4benzoformylpyrazolone5)smethylthiosemicarbazone(PMBPMTSC), were synthesized and characterized by elemental analysis, MS, IR spectra, NMR spectra. The crystal structure of the photocolored product of PMBPTSC was determined by single crystal XRD analysis. The results show that the photochromic phenomenon is due to the photoisomerization from enol form to keto form. Their photochromic properties were studied by powderUV reflectance spectra under the irradiation of 200—380 nm light. The firstorder rate constants of the photocoloring reaction were found to be 780×10 -3 s -1 for compound 1A and 103×10 -3 s -1 for compound 2A. 展开更多
关键词 SYNTHESIS Crystal structure Pyrazolone-ring Photochromic compound
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Three-dimensional thermohaline anomaly structures of rings in the Kuroshio Extension region
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作者 Ya’nan Ding Chunsheng Jing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第3期25-35,共11页
Using AVISO satellite altimeter observations during 1993–2015 and a manual eddy detection method, a total of 276 anticyclonic rings and 242 cyclonic rings shed from the Kuroshio Extension(KE) were identified, and the... Using AVISO satellite altimeter observations during 1993–2015 and a manual eddy detection method, a total of 276 anticyclonic rings and 242 cyclonic rings shed from the Kuroshio Extension(KE) were identified, and their three-dimensional(3D) anomaly structures were further reconstructd based on the Argo float data and the Japan Agency for Marine-Earth Science and Technology(JAMSTEC) cruise and buoy data through an interpolation method. It is found that the cyclonic(anticyclonic) rings presented consistent negative(positive) anomalies of potential temperature;meanwhile the relevant maximum anomaly center became increasingly shallow for the cyclonic rings whereas it went deeper for the anticyclonic rings as the potential temperature anomaly decreased from the west to the east. The above deepening or shoaling trend is associated with the zonal change of the depth of the main thermocline. Moreover, the composite cold ring between 140° and 150°E was found to exhibit a double-core vertical structure due to the existence of mode water with low potential vorticity. Specifically, a relatively large negative(positive) salinity anomaly and a small positive(negative) one appeared for the composite cyclonic(anticyclonic) ring at the depth above and below 600 m, respectively. The underlying driving force for the temperature and salinity anomaly of the composite rings was also attempted, which varies depending on the intensity of the background current and the temperature and salinity fields in different areas of the KE region, and the rings’ influences on the temperature and salinity could reach deeper than 1 000 m on average. 展开更多
关键词 KUROSHIO Extension pinched-off ring THERMOHALINE ANOMALY THREE-DIMENSIONAL structure composite EDDY
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Ring Structures of Silicone Oligomers:a Density Functional Theory Study
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作者 程学礼 赵燕云 +1 位作者 韩银峰 张建平 《Journal of Donghua University(English Edition)》 EI CAS 2017年第5期646-652,共7页
Silicones can be cross-linked to materials with a wide variety of properties.In this work,the ringed oligomers of [SiO(OH)_2]nas well as the stacked structures of trimer and the linear strands of the dimer and trimer ... Silicones can be cross-linked to materials with a wide variety of properties.In this work,the ringed oligomers of [SiO(OH)_2]nas well as the stacked structures of trimer and the linear strands of the dimer and trimer were investigated systematically at B3 LYP/6-311 + + G(d,p) level combined with the conductor-like screening model(CPCM).This theoretical model reveals that,(1) SiO(OH)_2 will condense to stable ringed structures with SiO tetrahedrons;(2) in the ringed octamer [SiO(OH)_2]8,the macrocycle begins to pucker drastically;(3) from the linear strands of SiO rings it can be seen that the longer the chain is,the greater the energies decrease;(4) in [SiO(OH)_2]n(n ≥5) and in the strands of ringed oligomers,the highest occupied molecular orbitals(HOMOs) are primarily the n orbitals of the lone-pair electrons of oxygen atoms,so there are no delocalized π bonds. 展开更多
关键词 SILICONE B3LYP ring structure stacked structure linear strand
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Strain distributions and electronic structure of three-dimensional InAs/GaAs quantum rings
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作者 刘玉敏 俞重远 +5 位作者 贾博雍 徐子欢 姚文杰 陈智辉 芦鹏飞 韩利红 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第11期4667-4675,共9页
This paper presents a finite element calculation for the electronic structure and strain distribution of self-organized InAs/GaAs quantum rings. The strain distribution calculations are based on the continuum elastic ... This paper presents a finite element calculation for the electronic structure and strain distribution of self-organized InAs/GaAs quantum rings. The strain distribution calculations are based on the continuum elastic theory. An ideal three-dimensional circular quantum ring model is adopted in this work. The electron and heavy-hole energy levels of the InAs/GaAs quantum rings are calculated by solving the three-dimensional effective mass SchrSdinger equation including the deformation potential and piezoelectric potential up to the second order induced by the strain. The calculated results show the importance of strain and piezoelectric effects, and these effects should be taken into consideration in analysis of the optoelectronic characteristics of strain quantum rings. 展开更多
关键词 quantum ring strain distribution electronic structure
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Synthesis, Crystal Structure of [(MeC_5H_4)_2Ln(μ-OCH_2CH_2NMe_2)]_2 (Ln=Sm, Y, Nd) and Their Catalytic Activity for Ring-Opening Polymerization of ε-Caprolactone
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作者 邓明宇 周玉芳 +2 位作者 姚英明 沈琪 翁林红 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第5期505-509,共5页
Reaction of (MeC 5H 4) 3Ln with HOCH 2CH 2NMe 2 in tetrahydrofuran(THF) gives the new complexes [(MeC 5H 4) 2Ln(μ OCH 2CH 2NMe 2)] 2 (Ln=Sm, Y, Nd) with nitrogen functionalized μ alkoxide ligand. The ... Reaction of (MeC 5H 4) 3Ln with HOCH 2CH 2NMe 2 in tetrahydrofuran(THF) gives the new complexes [(MeC 5H 4) 2Ln(μ OCH 2CH 2NMe 2)] 2 (Ln=Sm, Y, Nd) with nitrogen functionalized μ alkoxide ligand. The complexes were characterized by elemental analysis and IR, and [(MeC 5H 4) 2Sm(μ OCH 2CH 2NMe 2)] 2 was structurally characterized by the X ray diffraction to be a dimer formed by two unsymmetric oxygen bridges. The complex has a tricyclic skeleton with the additional two Sm-N bonds via intramolecular coordination of OCH 2CH 2NMe 2. The coordination number of the central metal Sm is nine. The title complexes show good catalytic activity for ring opening polymerization of ε caprolactone. 展开更多
关键词 inorganic chemistry nitrogen functionalized alkoxide complex crystal structure ring opening polymerization ε caprolactone rare earths
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Formation of Hybrid Ring Structure of Cyanurate/Isocyanurate in the Reaction be-tween 2,4,6-Tris(4-Phenyl-Phenoxy)-1, 3,5-Triazine and Phenyl Glycidyl Ether
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作者 Daisuke Ohno Kazuya Zenyoji +2 位作者 Youji Kurihara Kazuyoshi Ueda Hitoshi Habuka 《International Journal of Organic Chemistry》 CAS 2016年第2期117-125,共9页
Reaction products of 2,4,6-tris(4-phenyl-phenoxy)-1,3,5-triazine derived from 4-phenylphenol cyanate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound w... Reaction products of 2,4,6-tris(4-phenyl-phenoxy)-1,3,5-triazine derived from 4-phenylphenol cyanate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound which were well known as reaction products of cyanate esters and epoxy resins, compounds with hybrid ring structure of cyanurate/isocyanurate were determined. Gibbs free energies of the compound having hybrid ring structure of cyanurate/isocyanurate with two isocyanurate moiety were found to be lower than that of the compound with cyanurate ring structure through calculations. Calculation data supported the existence of hybrid ring structure of cy-anurate/isocyanurate. It was revealed that isomerization from cyanurate to isocyanurate occurs via hybrid ring structure of cyanurate/isocyanurate in the reaction of aryl cyanurate and epoxy. 展开更多
关键词 Reaction products of 2 4 6-tris(4-phenyl-phenoxy)-1 3 5-triazine derived from 4-phenylphenol cya-nate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound which were well known as reaction products of cyanate esters and epoxy resins compounds with hybrid ring structure of cyanurate/isocyanurate were determined. Gibbs free energies of the compound having hybrid ring structure of cyanurate/isocyanurate with two isocyanurate moiety were found to be lower than that of the compound with cyanurate ring struc-ture through calculations. Calculation data supported the existence of hybrid ring structure of cy-anurate/isocyanurate. It was revealed that isomerization from cyanurate to isocyanurate occurs via hybrid ring structure of cyanurate/isocyanurate in the reaction of aryl cyanurate and epoxy.
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Mononuclear and Dinuclear Yttrium Complexes Supported by Pyrrolide Ligands: Syntheses, Structures and Catalytic Behaviors towards the Ring-opening Polymerization of ε-Caprolactone 被引量:1
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作者 裴浩 陆宁 +5 位作者 刘玮 陈砚美 吴冰 李海燕 李亚红 李武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第7期1085-1092,共8页
The syntheses, structures and catalytic activities of two yttrium complexes supported by pyrrolide ligands are reported. Treatment of Y(N(Si Me3)2)3 with one equivalent of H3bptd(H3bptd = 1,9-bis(2-pyrrolyl)-2,... The syntheses, structures and catalytic activities of two yttrium complexes supported by pyrrolide ligands are reported. Treatment of Y(N(Si Me3)2)3 with one equivalent of H3bptd(H3bptd = 1,9-bis(2-pyrrolyl)-2,5,8-triazanona-1,8-diene) in THF gave a complex of composition [Y(bptd)(THF)]2(1). Reaction of Y(N(Si Me3)2)3 with one equivalent of H3tpa(H3tpa = tris(pyrrolyl-α-methyl)amine) in THF generated [Y(tpa)(THF)3](2) in good yield. Complexes 1and 2 have been characterized by single-crystal X-ray diffraction, elemental analyses and NMR spectroscopy. Complex 1 is dinuclear. The two metal centers are doubly bridged by two amine nitrogen atoms to form a Y–N–Y–N four-membered rhombus ring. The geometries of Y^3+ ions in 1and 2 are well described as pentagonal bipyramid and capped octahedron, respectively. The ring-opening polymerization reactions of ε-caprolactone initiated by 1 and 2, respectively, were investigated. They both exhibited good catalytic activity for the polymerization of ε-caprolactone. All of the obtained polymers have high molecular weights and relatively narrower PDIs. The polymers generated by 2 possessed polydispersity close to 1.1. The good catalytic activities of 1 and 2 reveal their potential applications in polymer industry. 展开更多
关键词 yttrium pyrrolide ligand synthesis crystal structure ring-opening polymerization
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Eigenvalue Spectrum and Synchronizability of Double-Layer Directed Ring Networks
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作者 Ping Wu Zhen Jia +1 位作者 Feimei Yang Jiaquan Huang 《Journal of Applied Mathematics and Physics》 2021年第12期3067-3087,共21页
The synchronizability of multiplex undirected regular networks has been intensively studied based on the study of the synchronizability of single-layer networks. However, most real networks are characterized by some d... The synchronizability of multiplex undirected regular networks has been intensively studied based on the study of the synchronizability of single-layer networks. However, most real networks are characterized by some degree of directionality. So multiplex directed networks can better explain the synchronizability phenomenon. Here, based on the theory of master stability function (MSF), we study the eigenvalue spectrum and synchronizability of double-layer inter-layer directed ring networks (Networks-A) and double-layer intra-layer directed ring networks (Networks-B). The eigenvalue spectrum of the supra-Laplacian matrix of the networks is rigorously derived, and the influence of the networks structure parameters on the network’s synchronizability is analyzed. The correctness of the theory is further verified by numerical simulation analysis. Finally, the synchronizability of four kinds of double-layer ring networks with different coupling modes, namely, Networks-A, Networks-B, Networks-C (double-layer undirected ring networks), and Networks-D (double-layer undirected inter-layer random-added-edge ring networks), is compared and the results can provide guidance for constructing the optimal synchronization network. 展开更多
关键词 double-layer ring Networks Eigenvalue Spectrum SYNCHRONIZABILITY
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Time structure measurement of the SSRF storage ring using TRXEOL method 被引量:1
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作者 张招红 姜政 +1 位作者 薛松 郑丽芳 《Nuclear Science and Techniques》 SCIE CAS CSCD 2015年第4期22-27,共6页
In order to do alignment between the timing signal and the synchrotron X-ray pulse on the sample spot in the time domain,measuring time structure of the storage ring on the sample spot inside the experimental hutch is... In order to do alignment between the timing signal and the synchrotron X-ray pulse on the sample spot in the time domain,measuring time structure of the storage ring on the sample spot inside the experimental hutch is a foundational step during the time-resolved experiments using the pulsed synchrotron X-rays with the time structure defined by the storage ring.In this work,the method of time-resolved X-ray excited optical luminescence(TRXEOL)was designed and implemented to do the measurement.It is based on the principle of time-correlated single photon counting techniques.The measurement system consists of a spectrometer with a detector of photomultiplier tube,a timing system,a set of nuclear instrument modules and a luminescent material of zinc oxide.The measurement was performed on the X-ray absorbed fine structure spectrum beamline at Shanghai Synchrotron Radiation Facility.The results show that this method can be used to measure the time structure of the storage ring with a precision of less than 1 ns.The measurement system can also be used for the time-resolved research for the optical luminescent materials. 展开更多
关键词 上海同步辐射装置 测量系统 时间结构 储存环 X射线吸收精细结构 光致发光材料 X射线脉冲 光源
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Control of slow light in a ring-out-ring structure
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作者 王楠 掌蕴东 袁萍 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期316-322,共7页
This paper proposes a ring-out-ring structure of coupled optical resonators to yield coupled-resonator-induced transparency (CRIT). Considering the insertion loss of the coupler, it theoretically deduces the transmi... This paper proposes a ring-out-ring structure of coupled optical resonators to yield coupled-resonator-induced transparency (CRIT). Considering the insertion loss of the coupler, it theoretically deduces the transmission and the effective phase shift. The influences of the insertion loss of the coupler on the transmittance, the effective phase shift, the group index and the CRIT linewidth are fully studied. We find that the increase in multiple m can effectively enhance the normal dispersion and the group index of the proposed structure. Moreover, the specific expression of the group index at resonance is theoretically deduced and discussed for the proposed structure with two rings. The result shows that the multiple m between the lengths of ring 1 and ring 2 can enhance the group index to m times that of the structure with two equal-sized rings at resonance. The control of slow light in the proposed structure is important for applications of highly sensitivity gyroscopes, optical delay lines and optical buffers, etc. 展开更多
关键词 ring-out-ring structure DISPERSION group index slow light
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Interaction of Al-induced peptide backbone ring structure with the sidechains of His, Phe, Trp and Tyr
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作者 吴清雷 宋波 《Nuclear Science and Techniques》 SCIE CAS CSCD 2015年第4期90-94,共5页
Aluminium is widely used as an antimicrobial coagulant,food additive,and cookware.However,many reports indicate that aluminium may be a critical factor in many amyloid diseases,such as Alzheimer’s disease and Parkin... Aluminium is widely used as an antimicrobial coagulant,food additive,and cookware.However,many reports indicate that aluminium may be a critical factor in many amyloid diseases,such as Alzheimer’s disease and Parkinson’s disease.Unfortunately,the underlying mechanism is still poorly understood,which limits efforts to prevent and treat these diseases.In this paper,using an ab initio method,we studied the interaction of Al-backbone ring structure with theπ-electron-rich sidechains of His,Phe,Trp,and Tyr.We found that in the absence of water,the Al-backbone ring can stably bind with those sidechains.In the presence of water,the Al-backbone ring can bind to the His sidechain and cannot bind to the other sidechains.As revealed by further investigations,this could be attributed to the fact that there was a coordinate bond of the Al-backbone ring with the His sidechain,while there were theπ-πstacking and cation-π-like interactions with the other sidechains.These findings potentially provide a molecular understanding of Al-related toxicity,and may be helpful in designing drugs for those aforementioned aluminum-linked diseases and encourage treatment of Al-polluted water. 展开更多
关键词 相互作用 苯丙氨酸 环结构 酪氨酸 色氨酸 侧链 阿尔茨海默氏病 导肽
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RING-MORPHOSTRUCTURES OF THE AMUR-SONGHUA-HUANGHE LINEAMENT (EASTERN MARGIN OF ASIA)
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作者 A P Kulakov Shan-wen Qiu +4 位作者 E A Miasnikov Xi-kui Wang S M Tashchi Hua-chang Zhao Chang-chun Song 《Chinese Geographical Science》 SCIE CSCD 2000年第4期61-68,共8页
: The“ ring-morphostructures” (RM) are the object of this study. They are one of the most significant element of lineament’s structure and unknown for the majority of investigations. RM are numerous to lineament’... : The“ ring-morphostructures” (RM) are the object of this study. They are one of the most significant element of lineament’s structure and unknown for the majority of investigations. RM are numerous to lineament’s zone: they have different size (from 10-20km to 500-800km in diameter), structure, age, geological history and have been divided into several classes on the most important signs. They have a spatial-genetic connection Amur-Songhua-Huanghe lineament (ASHL) and had been developed simultaneously with it. The RM exerted an essential influence on the geologic-geomorphological structure, evolution and geodynamics of lineament. The main factor of evolution of lineament is a long geological process of extension of the earth’s crust which is a result of the expanding earth. 展开更多
关键词 ring-morphostructure LINEAMENT structure East ASIP
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Ring-opened Crystal Structure and Photochromism of 2,2-Bis(4-tertiary butyl phenyl)-3H-naphtho[2,1-b]pyran
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作者 谈廷风 庞美丽 吴边鹏 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第2期187-190,共4页
The title compound, 2,2-bis(4-tertial butyl phenyl) naphthopyran, has been prepared and characterized by means of IR, ^1H NMR and elemental analysis, and its crystal structure was determined with X-ray diffraction i... The title compound, 2,2-bis(4-tertial butyl phenyl) naphthopyran, has been prepared and characterized by means of IR, ^1H NMR and elemental analysis, and its crystal structure was determined with X-ray diffraction in the ring-opened form after hydrolyzation. It belongs to monoclinic, space group P21/c, with a = 14.358(3), b = 7.6725(15), c = 24.470(5) А, β= 97.147(4)°, C_33H_36O2, Mr=464.62, V= 2674.8(9)А^3, Z = 4, Dc = 1.154 g/cm^3,μ= 0.070 mm^-1, F(000) = 1000, the final R = 0.0514 and wR = 0.1272 for 5444 observed reflections (I 〉 2σ(I)). X-ray analysis revealed that the C(13)-O(1) bond of the title compound cracks after UV irradiation, the six-membered heterocycles are destroyed, and zwitterionic intermediates come into being. The molecular structure in the ring-opened form is obtained after hydrolyzation. It is infrequent that the single-crystal structure is determined in a ring-opened form. A two-dimensional framework is formed by O-H…O and CAr-H…O hydrogen bonds. The UV-vis spectra show that the title compound exhibits excellent photochromic properties in solutions and polymers. 展开更多
关键词 NAPHTHOPYRAN ring-opened form crystal structure PHOTOCHROMISM
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