Recent development of UV-B laser diodes

2021 ◽  
Author(s):  
Motoaki Iwaya ◽  
Shunya Tanaka ◽  
Tomoya Omori ◽  
Kazuki Yamada ◽  
Ryota Hasegawa ◽  
...  
Keyword(s):  
Layer Structure ◽  
High Current Density ◽  
Optical Cavity ◽  
Laser Diodes ◽  
Semiconductor Layer ◽  
Current Status ◽  
Laser Oscillation ◽  
Future Expectations ◽  
Future Challenges ◽  
History Of

Abstract This review paper describes the history of development, current issues, and future expectations of UV-B laser diodes, which are expected to be adopted in various applications such as microfabrication and biotechnology in the near future. In order to achieve room temperature operation of this device, there were several challenges are remained, including the development of a crystal growth technique of high crystalline quality AlGaN that enables a laser oscillation with a low excitation carrier density, and the development of a semiconductor layer structure that simultaneously formation of a desirable optical cavity and injection of high density carriers (operation of high current density) to active layer allowing for laser oscillation. These challenges and the technologies that have overcome them are reviewed. Current status of the device characteristics and future challenges are also discussed.

scholarly journals Counseling in Turkey: Current Status and Future Challenges

1998 ◽  
Vol 6 ◽  
pp. 12 ◽  
Author(s):  
Suleyman Dogan
Keyword(s):  
Current Status ◽  
The Future ◽  
Future Challenges ◽  
History Of

In this article a special emphasis is placed on the current status and the future challenges of counseling in Turkey. A brief history of counseling in Turkey, current developments, and the basic issues in this field are pointed out. Finally, the future challenges and recommendations to improve the current status of counseling are discussed.

Strategies for Survival of the World — Risk Management

2019 ◽  
Vol 10 (4) ◽  
Author(s):  
Jovo Lojanica ◽  
Keyword(s):  
Risk Management ◽  
Native Americans ◽  
National Level ◽  
Country Level ◽  
Management Standards ◽  
Family Level ◽  
Future Challenges ◽  
Iso 31000 ◽  
History Of ◽  
Personal Level

All management standards have requirements for different aspects of improvements on the personal level, family level, company level, in business and life. What is about national level and country level? Is it possible for today’s generations to learn history of nations and of civilizations? If it is — ok, let’s apply it on actual time and people to have less problems and difficulties — especially if is actual in field of risk management. Majority of people are occupied by today’s problems. They don’t consider past and future challenges. People from each country strive for better quality, better and cleaner environment, higher safety etc. historically and today. But could we remember: How did Genghis Khan conquer many regions and how was he defeated? How did Mayas and Aztecs die out? How were Native Americans in North America drastically reduced in numbers? How did the Roman Imperium vanish? How was the Ottoman Imperium established and how it vanished? How many people were killed in the wars in XX century, etc? In all these catastrophic changes risks were not considered in an adequate way. Requirements of risk management — Principles and guidelines — ISO 31000:2009 are very consultative. They could be used on country level, national level, regional level, continental and intercontinental level.

scholarly journals Technologies for Water Reuse: Current Status and Future Challenges

Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 832
Author(s):  
Mauro Capocelli ◽  
Vincenzo Piemonte
Keyword(s):  
Sustainable Development ◽  
Water Reuse ◽  
Food Production ◽  
Current Status ◽  
The Sustainable Development ◽  
Future Challenges

Water is fundamental for the quality of both ecosystems and society, and plays a key role for energy and food production, a prerequisite for the sustainable development [...]

scholarly journals Canada’s history of failing to provide medical care for Indigenous children

2020 ◽  
Author(s):  
Rakhshan Kamran
Keyword(s):  
Health Care ◽  
Human Rights ◽  
First Nations ◽  
Social Services ◽  
Current Status ◽  
House Of Commons ◽  
Canadian Government ◽  
Indigenous Children ◽  
History Of ◽  
Services And Supports

Abstract In December 2007, the House of Commons unanimously supported Jordan’s Principle, a commitment that all First Nations children would receive the health care products, social services, and supports, and education they need, in memory of Jordan River Anderson. However, the process of applying for Jordan’s Principle was convoluted and not transparent, leaving several cases not being responded to. The Canadian Human Rights Tribunal found the definition and implementation of Jordan’s Principle to be racist and discriminatory in 2016, ordering the Canadian government to make immediate changes. Failing to make changes to Jordan’s Principle, the Canadian government was found to be noncompliant with the Canadian Human Rights Tribunal orders in 2018. This article provides one case example of Jordan’s Principle that was not responded to, details on the current status of Jordan’s Principle, and information on the recent implementation of the Act respecting First Nations, Inuit and Métis children, youth and families.

Nonisolated Electric Vehicle Chargers: Their Current Status and Future Challenges.

2021 ◽  
Vol 9 (2) ◽  
pp. 23-33
Author(s):  
Jin Wang ◽  
Yue Zhang ◽  
Mohamed Elshaer ◽  
William Perdikakis ◽  
Chengcheng Yao ◽  
...  
Keyword(s):  
Electric Vehicle ◽  
Current Status ◽  
Future Challenges

scholarly journals Development of an Understanding of Reactive Mercury in Ambient Air: A Review

Atmosphere ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 73
Author(s):  
Mae Sexauer Gustin ◽  
Sarrah M. Dunham-Cheatham ◽  
Jiaoyan Huang ◽  
Steve Lindberg ◽  
Seth N. Lyman
Keyword(s):  
Ambient Air ◽  
Automated System ◽  
Current Status ◽  
Measurement Systems ◽  
Power Plant Emissions ◽  
History Of ◽  
Plant Emissions ◽  
Gas Measurements ◽  
Future Work ◽  
Stack Gas

This review focuses on providing the history of measurement efforts to quantify and characterize the compounds of reactive mercury (RM), and the current status of measurement methods and knowledge. RM collectively represents gaseous oxidized mercury (GOM) and that bound to particles. The presence of RM was first recognized through measurement of coal-fired power plant emissions. Once discovered, researchers focused on developing methods for measuring RM in ambient air. First, tubular KCl-coated denuders were used for stack gas measurements, followed by mist chambers and annular denuders for ambient air measurements. For ~15 years, thermal desorption of an annular KCl denuder in the Tekran® speciation system was thought to be the gold standard for ambient GOM measurements. Research over the past ~10 years has shown that the KCl denuder does not collect GOM compounds with equal efficiency, and there are interferences with collection. Using a membrane-based system and an automated system—the Detector for Oxidized mercury System (DOHGS)—concentrations measured with the KCl denuder in the Tekran speciation system underestimate GOM concentrations by 1.3 to 13 times. Using nylon membranes it has been demonstrated that GOM/RM chemistry varies across space and time, and that this depends on the oxidant chemistry of the air. Future work should focus on development of better surfaces for collecting GOM/RM compounds, analytical methods to characterize GOM/RM chemistry, and high-resolution, calibrated measurement systems.

scholarly journals Imaging Response of Antiangiogenic and Immune-Oncology Drugs in Metastatic Renal Cell Carcinoma (mRCC): Current Status and Future Challenges

Kidney Cancer ◽  
2017 ◽  
Vol 1 (2) ◽  
pp. 107-114 ◽  
Author(s):  
Laure Fournier ◽  
Alexandre Bellucci ◽  
Yann Vano ◽  
Mehdi Bouaboula ◽  
Constance Thibault ◽  
...  
Keyword(s):  
Renal Cell Carcinoma ◽  
Cell Carcinoma ◽  
Metastatic Renal Cell Carcinoma ◽  
Renal Cell ◽  
Current Status ◽  
Future Challenges ◽  
Immune Oncology ◽  
Imaging Response

scholarly journals The Swiss Industrial Biocatalysis Consortium (SIBC): Past, Present and Future

2020 ◽  
Vol 74 (5) ◽  
pp. 342-344
Author(s):  
Steven Hanlon
Keyword(s):  
Knowledge Sharing ◽  
Fine Chemicals ◽  
Special Edition ◽  
Founding Fathers ◽  
Future Challenges ◽  
History Of

Since its inception in 2004, the Swiss Industrial Biocatalysis Consortium (SIBC) has brought together scientists from the Pharma, Fine Chemicals, Agrochemicals and Flavor and Fragrance Industries with the goal of promoting biocatalysis inside and outside of Switzerland as well as providing mutual benefits in the form of pre-competitive knowledge sharing. One of the 'founding fathers' of the SIBC was of course Oreste Ghisalba, whom we are honoring here in this special edition. The history of the SIBC as well as current activities and future challenges will be presented.

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