scholarly journals A critical transition in leaf evolution facilitated the Cretaceous angiosperm revolution

2012 ◽  
Vol 3 (1) ◽  
Author(s):  
Hugo Jan de Boer ◽  
Maarten B. Eppinga ◽  
Martin J. Wassen ◽  
Stefan C. Dekker
Keyword(s):  
Critical Transition ◽  
Leaf Evolution

El Museo Universal (1857-69): Mirror of Transition Years

PMLA ◽  
1955 ◽  
Vol 70 (3) ◽  
pp. 350-374
Author(s):  
John E. Englekirk
Keyword(s):  
19Th Century ◽  
Spanish Literature ◽  
Critical Transition ◽  
Partial Coverage ◽  
Partial Analysis ◽  
Literary Journals ◽  
The 19Th Century

Students of Spanish literature of the first half of the 19th century still stand indebted to Georges Lc Centil for his partial analysis of and index to thirty-one literary journals published in :Madrid between 1803 and 1849. More recently additional light has been thrown on this period through the publication of complete indices for a number of reviews not covered by Le Gentil as well as for several included in his survey. Thus far, however, there has been no planned approach to duplicate the above efforts for the critical transition years, roughly 1850–70, from the decline of romanticism to the triumph of realism. The CSIC series to clate includes only two reviews that afford but partial coverage for these years: the above-cited Semanario pintoresco espanol (1836-57) and Educación pintoresca (1857-59). The latter, moreover, is of scant literary significance.

scholarly journals The first year on haemodialysis: a critical transition

2015 ◽  
Vol 8 (3) ◽  
pp. 271-277 ◽  
Author(s):  
Natascha J.H. Broers ◽  
Anne C.M. Cuijpers ◽  
Frank M. van der Sande ◽  
Karel M.L. Leunissen ◽  
Jeroen P. Kooman
Keyword(s):  
First Year ◽  
Critical Transition

Correlation between oxygen excess density and critical transition temperature in superconducting Bi-2201, Bi-2212 and Bi-2223

2008 ◽  
Vol 63 (11-12) ◽  
pp. 1372-1375 ◽  
Author(s):  
H.P. Roeser ◽  
F. Hetfleisch ◽  
F.M. Huber ◽  
M.F. von Schoenermark ◽  
M. Stepper ◽  
...  
Keyword(s):  
Transition Temperature ◽  
Critical Transition ◽  
Critical Transition Temperature ◽  
Excess Density ◽  
Oxygen Excess

Critical current density and microstructure variations in YBa2Cu3O7−x + BaSnO3 films with different concentrations of BaSnO3

2008 ◽  
Vol 23 (12) ◽  
pp. 3363-3369 ◽  
Author(s):  
C.V. Varanasi ◽  
J. Burke ◽  
L. Brunke ◽  
H. Wang ◽  
J.H. Lee ◽  
...  
Keyword(s):  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Gradual Increase ◽  
Critical Transition ◽  
Critical Transition Temperature ◽  
Transmission Electron ◽  
Order Of Magnitude ◽  
High Fields ◽  
Magnitude Increase

Previous work on YBa2Cu3O7−x (YBCO) + BaSnO3 (BSO) films with a single composition showed significant critical current density (Jc) improvements at higher fields but lowered Jc in low fields. A detailed study on BSO concentrations provided here demonstrates that significant Jc enhancement can occur even up to 20 mol% BSO inclusion, where typical particulate inclusions in these concentrations degrade the YBCO performance. YBCO + BSO films were processed on (100) LaAlO3 substrates using premixed targets of YBa2Cu3O7-x (YBCO) with additions of 2, 4, 10, and 20 mol% BSO. The critical transition temperature Tc of the films remained high (>87 K), even with large amounts (20 mol%) of BSO. YBCO + BSO films showed a gradual increase in Jc at high fields as the amount of BSO was increased. More than an order of magnitude increase in Jc was measured in YBCO + BSO samples as compared to regular YBCO at 4 T. YBCO + 10 mol% BSO films showed overall improvement at all the field ranges while YBCO + 20 mol% BSO was better only at high fields. Transmission electron microscopy revealed the presence of ∼7–8-nm-diameter BSO nanocolumns, the density of which increased with increasing BSO content correlating well with the observed improvements in Jc.

scholarly journals Erratum: Corrigendum: Origami structures with a critical transition to bistability arising from hidden degrees of freedom

2015 ◽  
Vol 14 (5) ◽  
pp. 540-540 ◽  
Author(s):  
Jesse L. Silverberg ◽  
Jun-Hee Na ◽  
Arthur A. Evans ◽  
Bin Liu ◽  
Thomas C. Hull ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Critical Transition

What's in a Name - Transition State or Critical Transition Structure?

1995 ◽  
Vol 72 (1) ◽  
pp. 13 ◽  
Author(s):  
S. H. Bauer ◽  
C. F. Wilcox
Keyword(s):  
Transition State ◽  
Critical Transition ◽  
Transition Structure

Finite Element and Experimental Analysis of Edge Defects Formation during Orthogonal Cutting of SiCp/Al Composites

2012 ◽  
Vol 500 ◽  
pp. 146-151 ◽  
Author(s):  
Ning Hou ◽  
Li Zhou ◽  
Shu Tao Huang ◽  
Li Fu Xu
Keyword(s):  
Finite Element ◽  
Chip Formation ◽  
Defect Formation ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
Rake Angle ◽  
Critical Transition ◽  
Cutting Depth ◽  
Edge Defect ◽  
Edge Defects

In this paper, a finite element method was used to dynamically simulate the process of the edge defects formation during orthogonal cutting SiCp/Al composites. The influence of the cutting speed, cutting depth and rake angle of the PCD insert on the size of the edge defects have been investigated by using scanning electron. According to the simulated results, it can be provided that the cutting layer material has an effect on transfer stress and hinder the chip formation in the critical transition stage, and the critical transition point and distance are defined in this stage. The negative shear phenomenon is found when the chip transit to the edge defects in the flexure deformation stage, so the process of the chip formation is the basis of the edge defects formation. In addition, the relationship between the nucleation and propagation direction of the crack and the variation of the edge defect shape on the workpiece was investigated by theory, and it found that the negative shear angle formation is the primary cause of the edge defect formation. A mixed mode crack is found in the crack propagation stage. The sizes of edge defects were measured by the experiment and simulation, and the edge defect size decrease with the increasing of tool rake angle, while increase with increasing cutting depth and cutting speed.

Analysis of the mechanism of the critical transition in irradiated acetylene that leads to generation of shell-shaped carbon nanoparticles

Carbon ◽  
2005 ◽  
Vol 43 (13) ◽  
pp. 2693-2700 ◽  
Author(s):  
Igor S. Altman ◽  
Mansoo Choi
Keyword(s):  
Carbon Nanoparticles ◽  
Critical Transition

Impact of cyber dependencies in critical infrastructures: The reliability of grid splitting in power systems

2018 ◽  
Vol 232 (5) ◽  
pp. 491-504 ◽  
Author(s):  
Di-An Tian ◽  
Giovanni Sansavini
Keyword(s):  
Communication Network ◽  
Power System ◽  
Test System ◽  
System Stability ◽  
Critical Infrastructures ◽  
Delay Model ◽  
Critical Transition ◽  
Open Communication ◽  
Transition Range ◽  
Traffic Uncertainty

The growing presence of cyber interdependencies in critical infrastructures can be exemplified by grid splitting, which is an application in power system stability and control dependent on communication services. It involves the controlled separation of a power system into islands in reaction to an imminent instability. Communication is necessary for gathering system-wide synchronized measurements for state estimation as well as for the dispatch of line switch-opening signals. However, grid splitting may become ineffective due to a degradation in communication, which is accrued by the use of non-dedicated, open communication networks. To address this issue, this article aims to quantify the reliability of grid splitting under degraded communication conditions. A simulation framework is developed that allows the integration of a transient electrical model and a stochastic communication delay model that captures the effects of congestion and traffic uncertainty. The application to the IEEE 39-Bus Test System shows that the reliability of grid splitting is reduced under the influence of degraded communication leading to increased time delays. Furthermore, the results identify a critical transition range in the grid splitting reliability for a very narrow range of external interfering traffic and network data rate. Finally, the interdependency of the electric and the communication network is quantified by the expected efficiency of the communication network subject to degraded communication following the grid splitting action. The decrease in the expected communication efficiency under degraded communication is driven by increased congestion levels and by failures of electrical and co-located communication nodes and is related to the critical transition range for reliability. The developed methodology allows identifying the communication requirements for a reliable grid splitting execution under traffic uncertainty and congestion.

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