Synthesis of hierarchical ZSM-5 nano-aggregated microspheres for the application in enhancing the stability of n-hexane aromatization

Safety regulation is an important approach to secure the constructing process. A three-player regulation evolutionary game model is built, the stability analysis and simulation results show that evolutionary equilibrium (EE) does not exist, providing a convenient way for regulation policy making.

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DEVELOPING SELECTIVE OXIDATION CATALYSTS OF LIGHT ALKANES: FROM FUNDAMENTAL UNDERSTANDING TO RATIONAL DESIGN

Surface Review and Letters ◽

10.1142/s0218625x0700992x ◽

2007 ◽

Vol 14 (04) ◽

pp. 645-656 ◽

Cited By ~ 7

Author(s):

GANG FU ◽

XIAODONG YI ◽

CHUANJING HUANG ◽

XIN XU ◽

WEIZHENG WENG ◽

...

Keyword(s):

Selective Oxidation ◽

Rational Design ◽

Acid Sites ◽

Active Components ◽

Active Centers ◽

Light Alkanes ◽

Key Issues ◽

Spatial Isolation ◽

Oxygen Anions ◽

The Stability

Selective oxidation of light alkanes remains to be a great challenge for the wider use of alkanes as feedstocks. To achieve high activity and at the same time high selectivity, some key issues have to be addressed: (1) the stability of the desired products with respect to the reactants; (2) the roles of the active components in the catalysts, the structure and the functionality of the active centers; (3) the reducibility of the metal cations, the Lewis acid sites and their synergic effects with the basic sites of the lattice oxygen anions; (4) spatial isolation of the active centers; and (5) the mechanisms for the formation and transformation of the intermediates and their kinetic controls. In this contribution, we took selective oxidation of propane to acrolein as our target reaction, and reviewed mainly our own work, trying to provide some thinking and answers to these five questions.

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Hierarchical Structure of the Economic Potential of a Region

REGIONOLOGY ◽

10.15507/2413-1407.104.026.201803.422-437 ◽

2018 ◽

Vol 26 (3) ◽

pp. 422-437

Author(s):

Ekateryna V. Shcherbakova

Keyword(s):

Hierarchical Structure ◽

Simulation Method ◽

The State ◽

Economic Systems ◽

Economic Potential ◽

Fundamental Study ◽

Different Types ◽

The Hierarchical Structure ◽

The Stability ◽

Different Levels

Introduction. The economic potential of a region is a factor in positive trends in the development of economic systems and in the stability of the state in the inter-national arena. The mechanisms of such influence are based on internal processes taking place in the structure of the economic potential of a region. However, the lack of fundamental study of the structure of the economic potential of a region and the increased interest in this issue are topical and led to the choice of this research topic which is aimed at studying the internal structure of the economic potential of a region as well as at determining the characteristics of each of its elements. Materials and Methods. When determining the structure of the economic potential of a region, the methods of the empirical, experimental and theoretical levels were used such as the method of comparing different types of economic potential, the hypothetical and logical methods as well as the simulation method. Results. By comparing the types of economic potentials at different levels of func-tioning of the economy, the elements of the structure of the economic potential of a region were identified and analyzed, subordination between them was established. Presence of subordination made it possible to identify the hierarchical structure and to present it in the form of a 3 -level hierarchy. For a more accurate understanding of the links and significance of the hierarchy of types of the economic potential of a region, the meanings and components of each level of the hierarchy were described. Discussion and Conclusions. A hierarchical structure of the economic potential of a region was revealed due to the existence of subordination between the elements of the structure. The research materials may be useful when planning economic development of a region and the state in order to strengthen market positions and competitiveness. The data obtained are of value both for economists and scientists involved in the study of regional economy.

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SNP-based heritability estimation: measurement noise, population stratification, and stability

10.1101/040055 ◽

2016 ◽

Cited By ~ 4

Author(s):

Eric R. Gamazon ◽

Danny S. Park

Keyword(s):

Complex Traits ◽

Spectral Properties ◽

Population Stratification ◽

Genetic Architecture ◽

Genetic Relatedness ◽

Likelihood Function ◽

Snp Data ◽

Heritability Estimation ◽

Important Approach ◽

The Stability

Siddharth Krishna Kumar1 and co-authors claim to have shown that “GCTA applied to current SNP data cannot produce reliable or stable estimates of heritability.” Given the numerous recent studies on the genetic architecture of complex traits that are based on this methodology, these claims have important implications for the field. Through an investigation of the stability of the likelihood function under phenotype perturbation and an analysis of its dependence on the spectral properties of the genetic relatedness matrix, our study characterizes the properties of an important approach to the analysis of GWAS data and identified crucial errors in the authors’ analyses, invalidating their main conclusions.

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Improving the Stability and Catalyst Lifetime of the Halogenase RebH By Directed Evolution

ChemBioChem ◽

10.1002/cbic.201300780 ◽

2014 ◽

Vol 15 (9) ◽

pp. 1286-1289 ◽

Cited By ~ 50

Author(s):

Catherine B. Poor ◽

Mary C. Andorfer ◽

Jared C. Lewis

Keyword(s):

Directed Evolution ◽

The Stability ◽

Catalyst Lifetime

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A novel dynamics combination model reveals the hidden information of community structure

International Journal of Modern Physics C ◽

10.1142/s0129183115500436 ◽

2015 ◽

Vol 26 (04) ◽

pp. 1550043 ◽

Cited By ~ 7

Author(s):

Hui-Jia Li ◽

Huiying Li ◽

Chuanliang Jia

Keyword(s):

Phase Transition ◽

Community Structure ◽

Markov Process ◽

Dynamic System ◽

Hierarchical Structure ◽

Mathematical Explanation ◽

Stochastic Dynamic ◽

Hidden Information ◽

Multiple Timescales ◽

The Stability

The analysis of the dynamic details of community structure is an important question for scientists from many fields. In this paper, we propose a novel Markov–Potts framework to uncover the optimal community structures and their stabilities across multiple timescales. Specifically, we model the Potts dynamics to detect community structure by a Markov process, which has a clear mathematical explanation. Then the local uniform behavior of spin values revealed by our model is shown that can naturally reveal the stability of hierarchical community structure across multiple timescales. To prove the validity, phase transition of stochastic dynamic system is used to indicate that the stability of community structure we proposed is able to describe the significance of community structure based on eigengap theory. Finally, we test our framework on some example networks and find it does not have resolute limitation problem at all. Results have shown the model we proposed is able to uncover hierarchical structure in different scales effectively and efficiently.

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Open discussion

Symposium - International Astronomical Union ◽

10.1017/s0074180900029533 ◽

1982 ◽

Vol 99 ◽

pp. 605-613

Author(s):

P. S. Conti

Keyword(s):

Buenos Aires ◽

Large Mass ◽

List Type ◽

Common Phenomenon ◽

Open Discussion ◽

The Stability ◽

Ring Nebulae

Conti: One of the main conclusions of the Wolf-Rayet symposium in Buenos Aires was that Wolf-Rayet stars are evolutionary products of massive objects. Some questions:–Do hot helium-rich stars, that are not Wolf-Rayet stars, exist?–What about the stability of helium rich stars of large mass? We know a helium rich star of ∼40 MO. Has the stability something to do with the wind?–Ring nebulae and bubbles : this seems to be a much more common phenomenon than we thought of some years age.–What is the origin of the subtypes? This is important to find a possible matching of scenarios to subtypes.

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Symmetric Multistep Methods Revisited: II. Numerical Experiments

International Astronomical Union Colloquium ◽

10.1017/s0252921100031602 ◽

1999 ◽

Vol 173 ◽

pp. 309-314 ◽

Cited By ~ 3

Author(s):

T. Fukushima

Keyword(s):

Multistep Methods ◽

Computational Time ◽

Integration Time ◽

Implicit Methods ◽

Symmetric Methods ◽

Celestial Bodies ◽

The Stability ◽

Predictor Corrector ◽

Symmetric Multistep Methods ◽

Integration Errors

AbstractBy using the stability condition and general formulas developed by Fukushima (1998 = Paper I) we discovered that, just as in the case of the explicit symmetric multistep methods (Quinlan and Tremaine, 1990), when integrating orbital motions of celestial bodies, the implicit symmetric multistep methods used in the predictor-corrector manner lead to integration errors in position which grow linearly with the integration time if the stepsizes adopted are sufficiently small and if the number of corrections is sufficiently large, say two or three. We confirmed also that the symmetric methods (explicit or implicit) would produce the stepsize-dependent instabilities/resonances, which was discovered by A. Toomre in 1991 and confirmed by G.D. Quinlan for some high order explicit methods. Although the implicit methods require twice or more computational time for the same stepsize than the explicit symmetric ones do, they seem to be preferable since they reduce these undesirable features significantly.

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Uniformity of Magnification from Different Electron Microscopes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060179 ◽

1967 ◽

Vol 25 ◽

pp. 32-33

Author(s):

Godfrey C. Hoskins ◽

V. Williams ◽

V. Allison

Keyword(s):

Diffraction Grating ◽

The Other ◽

Carbon Replica ◽

Electron Microscopes ◽

The Stability

The method demonstrated is an adaptation of a proven procedure for accurately determining the magnification of light photomicrographs. Because of the stability of modern electrical lenses, the method is shown to be directly applicable for providing precise reproducibility of magnification in various models of electron microscopes.A readily recognizable area of a carbon replica of a crossed-line diffraction grating is used as a standard. The same area of the standard was photographed in Phillips EM 200, Hitachi HU-11B2, and RCA EMU 3F electron microscopes at taps representative of the range of magnification of each. Negatives from one microscope were selected as guides and printed at convenient magnifications; then negatives from each of the other microscopes were projected to register with these prints. By deferring measurement to the print rather than comparing negatives, correspondence of magnification of the specimen in the three microscopes could be brought to within 2%.

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