Growth and optical properties of (Y1−xGdx)3Al5O12:Ce single crystal phosphors for high-brightness neutral white LEDs and LDs

CrystEngComm ◽  
2016 ◽  
Vol 18 (25) ◽  
pp. 4799-4806 ◽  
Author(s):  
Stelian Arjoca ◽  
Daisuke Inomata ◽  
Yoshitaka Matsushita ◽  
Kiyoshi Shimamura
2016 ◽  
Author(s):  
Encarnación G. Víllora ◽  
Stelian Arjoca ◽  
Daisuke Inomata ◽  
Kiyoshi Shimamura

2015 ◽  
Vol 2 (5) ◽  
pp. 055503 ◽  
Author(s):  
Stelian Arjoca ◽  
Encarnación G Víllora ◽  
Daisuke Inomata ◽  
Kazuo Aoki ◽  
Yoshiyuki Sugahara ◽  
...  

2014 ◽  
Author(s):  
Encarnación G. Víllora ◽  
Stelian Arjoca ◽  
Kiyoshi Shimamura ◽  
Daisuke Inomata ◽  
Kazuo Aoki

Author(s):  
A. Strojnik ◽  
J.W. Scholl ◽  
V. Bevc

The electron accelerator, as inserted between the electron source (injector) and the imaging column of the HVEM, is usually a strong lens and should be optimized in order to ensure high brightness over a wide range of accelerating voltages and illuminating conditions. This is especially true in the case of the STEM where the brightness directly determines the highest resolution attainable. In the past, the optical behavior of accelerators was usually determined for a particular configuration. During the development of the accelerator for the Arizona 1 MEV STEM, systematic investigation was made of the major optical properties for a variety of electrode configurations, number of stages N, accelerating voltages, 1 and 10 MEV, and a range of injection voltages ϕ0 = 1, 3, 10, 30, 100, 300 kV).


Author(s):  
Arno J. Bleeker ◽  
Mark H.F. Overwijk ◽  
Max T. Otten

With the improvement of the optical properties of the modern TEM objective lenses the point resolution is pushed beyond 0.2 nm. The objective lens of the CM300 UltraTwin combines a Cs of 0. 65 mm with a Cc of 1.4 mm. At 300 kV this results in a point resolution of 0.17 nm. Together with a high-brightness field-emission gun with an energy spread of 0.8 eV the information limit is pushed down to 0.1 nm. The rotationally symmetric part of the phase contrast transfer function (pctf), whose first zero at Scherzer focus determines the point resolution, is mainly determined by the Cs and defocus. Apart from the rotationally symmetric part there is also the non-rotationally symmetric part of the pctf. Here the main contributors are not only two-fold astigmatism and beam tilt but also three-fold astigmatism. The two-fold astigmatism together with the beam tilt can be corrected in a straight-forward way using the coma-free alignment and the objective stigmator. However, this only works well when the coefficient of three-fold astigmatism is negligible compared to the other aberration coefficients. Unfortunately this is not generally the case with the modern high-resolution objective lenses. Measurements done at a CM300 SuperTwin FEG showed a three fold-astigmatism of 1100 nm which is consistent with measurements done by others. A three-fold astigmatism of 1000 nm already sinificantly influences the image at a spatial frequency corresponding to 0.2 nm which is even above the point resolution of the objective lens. In principle it is possible to correct for the three-fold astigmatism a posteriori when through-focus series are taken or when off-axis holography is employed. This is, however not possible for single images. The only possibility is then to correct for the three-fold astigmatism in the microscope by the addition of a hexapole corrector near the objective lens.


2020 ◽  
Vol 25 (46) ◽  
pp. 4848-4860 ◽  
Author(s):  
Anisha Anand ◽  
Gopinathan Manavalan ◽  
Ranju Prasad Mandal ◽  
Huan-Tsung Chang ◽  
Yi-Ru Chiou ◽  
...  

: The prevention and treatment of various infections caused by microbes through antibiotics are becoming less effective due to antimicrobial resistance. Researches are focused on antimicrobial nanomaterials to inhibit bacterial growth and destroy the cells, to replace conventional antibiotics. Recently, carbon dots (C-Dots) become attractive candidates for a wide range of applications, including the detection and treatment of pathogens. In addition to low toxicity, ease of synthesis and functionalization, and high biocompatibility, C-Dots show excellent optical properties such as multi-emission, high brightness, and photostability. C-Dots have shown great potential in various fields, such as biosensing, nanomedicine, photo-catalysis, and bioimaging. This review focuses on the origin and synthesis of various C-Dots with special emphasis on bacterial detection, the antibacterial effect of CDots, and their mechanism.


2021 ◽  
pp. 104468
Author(s):  
W.J. Choi ◽  
Y.I. Seo ◽  
Shin-ichi Kimura ◽  
Yong Seung Kwon

2021 ◽  
Vol 573 (1) ◽  
pp. 52-62
Author(s):  
Siddique Aneesa-Fatema ◽  
Y. B. Rasal ◽  
R. N. Shaikh ◽  
M. D. Shirsat ◽  
S. S. Hussaini ◽  
...  

2021 ◽  
Author(s):  
Shenglan Wang ◽  
Chong-Hua Zhang ◽  
Peisheng Zhang ◽  
Shu Chen ◽  
Zhi-ling Song ◽  
...  

Aggregation induced emission (AIE) dots have gained broad attention in fluorescence bioimaging and biosensor in virtue of their distinctive optical properties of splendid biocompatibility, high brightness and good photostability. However,...


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