scholarly journals FAxCs1–xPbI3 Nanocrystals: Tuning Crystal Symmetry by A-Site Cation Composition

2020 ◽  
Vol 5 (8) ◽  
pp. 2475-2482 ◽  
Author(s):  
Julian A. Vigil ◽  
Abhijit Hazarika ◽  
Joseph M. Luther ◽  
Michael F. Toney
2017 ◽  
Vol 5 (41) ◽  
pp. 21858-21865 ◽  
Author(s):  
Chen Hu ◽  
Yang Bai ◽  
Shuang Xiao ◽  
Teng Zhang ◽  
Xiangyue Meng ◽  
...  

Cation mixing has proved to be effective in stabilizing the high-temperature phase of formamidinium (FA)-based perovskites, affording high-performance n–i–p perovskite solar cells (PSCs).


ACS Nano ◽  
2018 ◽  
Vol 12 (10) ◽  
pp. 10327-10337 ◽  
Author(s):  
Abhijit Hazarika ◽  
Qian Zhao ◽  
E. Ashley Gaulding ◽  
Jeffrey A. Christians ◽  
Benjia Dou ◽  
...  

Author(s):  
O.L. Krivanek ◽  
J. TaftØ

It is well known that a standing electron wavefield can be set up in a crystal such that its intensity peaks at the atomic sites or between the sites or in the case of more complex crystal, at one or another type of a site. The effect is usually referred to as channelling but this term is not entirely appropriate; by analogy with the more established particle channelling, electrons would have to be described as channelling either through the channels or through the channel walls, depending on the diffraction conditions.


Author(s):  
Fred Eiserling ◽  
A. H. Doermann ◽  
Linde Boehner

The control of form or shape inheritance can be approached by studying the morphogenesis of bacterial viruses. Shape variants of bacteriophage T4 with altered protein shell (capsid) size and nucleic acid (DNA) content have been found by electron microscopy, and a mutant (E920g in gene 66) controlling head size has been described. This mutant produces short-headed particles which contain 2/3 the normal DNA content and which are non-viable when only one particle infects a cell (Fig. 1).We report here the isolation of a new mutant (191c) which also appears to be in gene 66 but at a site distinct from E920g. The most striking phenotype of the mutant is the production of about 10% of the phage yield as “giant” virus particles, from 3 to 8 times longer than normal phage (Fig. 2).


Author(s):  
Y. P. Lin ◽  
J. S. Xue ◽  
J. E. Greedan

A new family of high temperature superconductors based on Pb2Sr2YCu3O9−δ has recently been reported. One method of improving Tc has been to replace Y partially with Ca. Although the basic structure of this type of superconductors is known, the detailed structure is still unclear, and various space groups has been proposed. In our work, crystals of Pb2Sr2YCu3O9−δ with dimensions up to 1 × 1 × 0.25.mm and with Tc of 84 K have been grown and their superconducting properties described. The defects and crystal symmetry have been investigated using electron microscopy performed on crushed crystals supported on a holey carbon film.Electron diffraction confirmed x-ray diffraction results which showed that the crystals are primitive orthorhombic with a=0.5383, b=0.5423 and c=1.5765 nm. Convergent Beam Electron Diffraction (CBED) patterns for the and axes are shown in Figs. 1 and 2 respectively.


2014 ◽  
Vol 222 (1) ◽  
pp. 37-48 ◽  
Author(s):  
Stephanie Romney ◽  
Nathaniel Israel ◽  
Danijela Zlatevski

The present study examines the effect of agency-level implementation variation on the cost-effectiveness of an evidence-based parent training program (Positive Parenting Program: “Triple P”). Staff from six community-based agencies participated in a five-day training to prepare them to deliver a 12-week Triple P parent training group to caregivers. Prior to the training, administrators and staff from four of the agencies completed a site readiness process intended to prepare them for the implementation demands of successfully delivering the group, while the other two agencies did not complete the process. Following the delivery of each agency’s first Triple P group, the graduation rate and average cost per class graduate were calculated. The average cost-per-graduate was over seven times higher for the two agencies that had not completed the readiness process than for the four completing agencies ($7,811 vs. $1,052). The contrast in costs was due to high participant attrition in the Triple P groups delivered by the two agencies that did not complete the readiness process. The odds of Triple P participants graduating were 12.2 times greater for those in groups run by sites that had completed the readiness process. This differential attrition was not accounted for by between-group differences in participant characteristics at pretest. While the natural design of this study limits the ability to empirically test all alternative explanations, these findings indicate a striking cost savings for sites completing the readiness process and support the thoughtful application of readiness procedures in the early stages of an implementation initiative.


1976 ◽  
Vol 37 (C6) ◽  
pp. C6-23-C6-28 ◽  
Author(s):  
L. BROSSARD ◽  
H. OUDET ◽  
P. GIBART
Keyword(s):  

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