Design reliable and safe LED （light emitting diode） lighting equipment for potentially explosive atmospheres should require knowledge about the possible failure modes of LED sources. Nowadays, LED technology potenti...Design reliable and safe LED （light emitting diode） lighting equipment for potentially explosive atmospheres should require knowledge about the possible failure modes of LED sources. Nowadays, LED technology potential is not adequately considered by IECEx （International Electrotechnical Commission system for certification to standards relating to equipment for use in explosive atmospheres） yet. Standards only consider LEDs adequate for Zone 1 when luminary is realized by the Ex-d protection strategy, or ifa big limitation in terms of power is guarantee, for Ex-i mode. In particular, Ex-d LED luminaries are obtained by using heavy, thick and expensive flameproof enclosures, entrusting safety only to the mechanical strength of the case. Luminous efficiency＇s also reduced since the glass used is very thick （10% reduction of approximately every 10 mm of thickness of the glass）. The paper shows a study about different possible causes of LED failure and their implication with explosive atmospheres, investigating whether LED technology can be used safely with other safety strategy like Ex-e, which can guarantee better performance and less cost.展开更多
Third-row transition-metal complexes remain a key component in the preparation of light-emitting layers for future OLED technology.Hence,it is of utmost importance to expand their emission peak wavelengths into the tr...Third-row transition-metal complexes remain a key component in the preparation of light-emitting layers for future OLED technology.Hence,it is of utmost importance to expand their emission peak wavelengths into the true-blue(~460–470 nm)and near-infrared(NIR)regions(~700–1000 nm).Stable true-blue phosphors are expected to excel in commercially available lighting luminaries and visual devices,such as displays and monitors,while efficient NIR emitters will enable new applications such as sensing,imaging,and optical communication.In theory,these advanced emitters can be assembled using transition metals such as iridium and platinum and judiciously designed chelates,as elaborated in this chemistry frontier article.展开更多
We are deeply saddened that our beloved and respected friend and colleague Professor and Director Emeritus Winslow Briggs passed away peacefully on February 11,2019, at the age of 90. Winslow Briggs was a giant in the...We are deeply saddened that our beloved and respected friend and colleague Professor and Director Emeritus Winslow Briggs passed away peacefully on February 11,2019, at the age of 90. Winslow Briggs was a giant in the field of plant biology, an inspiring mentor, and a treasured colleague. He was also a beloved husband, father, and friend. We shall miss him dearly.展开更多
文摘Design reliable and safe LED （light emitting diode） lighting equipment for potentially explosive atmospheres should require knowledge about the possible failure modes of LED sources. Nowadays, LED technology potential is not adequately considered by IECEx （International Electrotechnical Commission system for certification to standards relating to equipment for use in explosive atmospheres） yet. Standards only consider LEDs adequate for Zone 1 when luminary is realized by the Ex-d protection strategy, or ifa big limitation in terms of power is guarantee, for Ex-i mode. In particular, Ex-d LED luminaries are obtained by using heavy, thick and expensive flameproof enclosures, entrusting safety only to the mechanical strength of the case. Luminous efficiency＇s also reduced since the glass used is very thick （10% reduction of approximately every 10 mm of thickness of the glass）. The paper shows a study about different possible causes of LED failure and their implication with explosive atmospheres, investigating whether LED technology can be used safely with other safety strategy like Ex-e, which can guarantee better performance and less cost.
基金supported by research funds from Innovation and Technology Fund(ITS/196/20)Research Grant Council(CityU 11304221 and 11312722)City University of Hong Kong,Hong Kong SAR.
文摘Third-row transition-metal complexes remain a key component in the preparation of light-emitting layers for future OLED technology.Hence,it is of utmost importance to expand their emission peak wavelengths into the true-blue(~460–470 nm)and near-infrared(NIR)regions(~700–1000 nm).Stable true-blue phosphors are expected to excel in commercially available lighting luminaries and visual devices,such as displays and monitors,while efficient NIR emitters will enable new applications such as sensing,imaging,and optical communication.In theory,these advanced emitters can be assembled using transition metals such as iridium and platinum and judiciously designed chelates,as elaborated in this chemistry frontier article.
文摘We are deeply saddened that our beloved and respected friend and colleague Professor and Director Emeritus Winslow Briggs passed away peacefully on February 11,2019, at the age of 90. Winslow Briggs was a giant in the field of plant biology, an inspiring mentor, and a treasured colleague. He was also a beloved husband, father, and friend. We shall miss him dearly.
