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1.
Industrialized white organic light-emitting diodes (OLEDs) currently require host-guest doping, a complicated process necessitating precise control of the guest concentration to get high efficiency and stability. Two doping-free, hybrid white OLEDs with fluorescent blue, and phosphorescent green and red emissive layers (EMLs) are reported in this work. An ultra-thin red phosphorescent EML was situated in a blue-emitting electron transport layer (ETL), while the ultra-thin green phosphorescent EML was placed either in the ETL (Device 1), or the hole transport layer (HTL) (Device 2). Device 2 exhibits higher efficiency and more stable spectrum due to the enhanced utilization of excitons by ultra-thin green EML at the exciton generation zone within the HTL. Values of current efficiency (CE), power efficiency (PE), and CRI obtained for the optimized hybrid white OLEDs fabricated through a doping-free process were of 23.2 cd/A, 20.5 lm/W and 82 at 1000 cd/m2, respectively. 相似文献
2.
《Planning》2019,(2)
2017年,美国心脏病学会和美国心脏协会提出将高血压诊断标准降为130/80 mm Hg (1 mm Hg=0. 133 kPa),这与其他指南有所不同。降压治疗的核心目标在于靶器官的保护,近年来降压治疗与脑小血管病预防的相关问题日益受到临床重视。目前研究结果表明,降压治疗对腔隙性卒中患者的二级预防以及白质病变进展的预防可能有一定积极意义,但确切的降压目标值并未确定。血压与临床结局可能呈现J型关系,血压过低或过高可能均有害,而取得最大获益的降压目标有待进一步探索。 相似文献
3.
现代民间青花与现代陶艺 总被引:1,自引:0,他引:1
现代民间青花与现代陶艺都是火与土的艺术,都具有粗犷,质朴、自然、大方的共同艺术特点。前者在传统民间青花的基础上,汲取了现代陶瓷科技成就和现代文化艺术成果,而发展成为富有现代艺术意蕴和现代审判内涵的新型民间青花艺术;而后者则是从传统陶艺延伸、扩展、蜕变为纯粹艺术表达和具有独特审判内涵的一门现代艺术。 相似文献
4.
将汉白玉废料通过高温煅烧分解得到氧化钙,再用氯化铵循环液溶解氧化钙制得碱性氯化钙溶液,除去其中的Mg、Fe等杂质得到氯化钙精制溶液,利用化学方法合成得到碳酸钙粉体.用X射线衍射(XRD)、扫描电镜(SEM)及激光粒度分析仪、白度仪对碳酸钙产品的晶相组成、形貌、粒度分布、白度及化学组成进行了分析,所得产品为纯度达98.5%以上、白度达97%以上、平均粒度为80nm左右的球形纳米级碳酸钙.并对碳化反应速率及合成球形纳米碳酸钙的影响因素进行了分析.实验中循环使用NH4Cl,氨的排放量小,减少了环境污染. 相似文献
5.
A Study of Shadowing on Indoor Visible-Light Wireless Communication Utilizing Plural White LED Lightings 总被引:3,自引:1,他引:2
Toshihiko Komine Shinichiro Haruyama Masao Nakagawa 《Wireless Personal Communications》2005,34(1-2):211-225
White LED is considered as a strong candidate for the future lighting technology. We have proposed an optical wireless communication
system that employs white LEDs for indoor wireless networks. In this system, LED is used not only as a lighting device, but
also as a communication device. The transmitter has large optical power and large emission characteristics to function as
lighting device. And the system has specific wireless channel impulse response differing from infrared wireless communication.
In this paper, we discuss about shadowing effect on the system utilizing plural LED lightings including the performance of
ISI based on the impulse response. We consider the downlink transmission based on TDMA and evaluate the shadowing effect caused
by pedestrians with computer simulation. When the shadowing often occurs at 800 Mb/s, the performance of outage call duration
rate and blocking rate are improved by using 3 LED lightings compared with 1 or 2 LED lightings. And, we show that the system
with the optimal number of the LED lighting is robust against shadowing and can accommodate more calls.
Toshihiko Komine was born in Shizuoka, Japan, on November 17, 1978. He received the B.E. and M.E. degrees in Information and Computer Science
from Keio University, Yokohama, Japan, in 2001 and 2003 respectively. He is currently studying for the Ph.D. degree at Department
of Information and Computer Science, Keio University. His current research interests are optical wireless communications and
LED communications.
Shinichiro Haruyama is a professor at Department of Information and Computer Science, Faculty of Science and Technology, Keio University, Yokohama,
Japan. He received an M.S. in engineering science from University of California at Berkeley in 1983 and a Ph.D. in computer
science from the University of Texas at Austin in 1990. He worked for Bell Laboratories of AT{&}T and Lucent Technologies,
U.S.A from 1991 to 1996, and for Sony Computer Science Laboratories, Inc. from 1998 to 2002. His research interests include
reconfigurable system, system design automation, wireless communication, and visible light communication.
Masao Nakagawa was born in Tokyo, Japan in 1946. He received the B.E., M.E. and Ph.D. degrees in electrical engineering from Keio University,
Yokohama, Japan, in 1969, 1971 and 1974 respectively. Since 1973, he has been with the Department of Electrical Engineering,
Keio University, where he is now a Professor. His research interests are in CDMA, consumer Communications, Mobile communications,
ITS (Intelligent Transport Systems), Wireless Home Networks, and Visible light Communication. He received 1989 IEEE Consumer
Electronics Society Paper Award, 1999-Fall Best Paper Award in IEEE VTC, IEICE Achievement Award in 2000, IEICE Fellow Award
in 2001. He was the executive committee chairman on International Symposium on Spread Spectrum Techniques and Applications
in 1992 and the technical program committee chairman of ISITA (International Symposium on Spread Spectrum Techniques and Applications)
in 1994. He is an editor of Wireless Personal Communications and was a guest editor of the special issues on “CDMA Networks
I, II, III and IV” published in IEEE JSAC in 1994 (I and II) and 1996 (III and IV). He chairs the Wireless Home Link sub-committee
in MMAC (Multimedia Mobile Access Communication Promotion Committee). 相似文献
6.
Ernest Marco‐Urrea Xavier Gabarrell Gloria Caminal Teresa Vicent C Adinarayana Reddy 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(9):1190-1196
BACKGROUND: Trichloroethylene (TCE) and perchloroethylene (PCE) are considered among the most important groundwater pollutants around the world. These compounds are usually found together in polluted environments but little is known about the ability of microorganisms to simultaneously degrade TCE and PCE. RESULTS: Data showed that several species of white‐rot fungi, including Trametes versicolor, Ganoderma lucidum, and Irpex lacteus, degrade substantial levels of TCE in pure culture. T. versicolor was chosen for further study since it degraded higher levels of TCE than the other organisms. Initial glucose concentration and reoxygenation of samples increased the amount of TCE dechlorination, but no significant difference in percentage TCE degradation was observed. T. versicolor was able to degrade 34.1 and 47.7% of PCE and TCE added as mixtures (containing 5 and 10 mg L−1, respectively). CONCLUSIONS: The degradation ability of TCE was extended to other species of white‐rot fungi. Percentage degradation as well as chloride release from mixtures of TCE and PCE showed that T. versicolor degrades mixtures of TCE and PCE almost as well as its ability to degrade individually added TCE or PCE. The results suggest the potential promise of T. versicolor for bioremediation of TCE and PCE in the environment. Copyright © 2008 Society of Chemical Industry 相似文献
7.
BC-1型白平衡仪是一种光电积分式测色仪器,它通过颜色传感器获取屏幕的红,绿,蓝三条色信号,与预先存储在仪器中的标准信号值相比较通过LED条形显示器显示两者之偏差,用以直接指导彩电生产线的白平衡调整,仪器采用Intel18098单片微机为系统核心,内藏信号发生器,仪器可任选红,绿,蓝作为基准色,具有基色亮度自动调整功能,该仪器的定标方法简单,快捷,可方便地存储8套基准白场标准数据,该仪器已可靠在应 相似文献
8.
9.
Brett J. Kagan Charlotte M. Ermine Stefano Frausin Clare L. Parish Jess Nithianantharajah Lachlan H. Thompson 《International journal of molecular sciences》2021,22(9)
Neonatal arterial ischemic stroke is one of the more severe birth complications. The injury can result in extensive neurological damage and is robustly associated with later diagnoses of cerebral palsy (CP). An important part of efforts to develop new therapies include the on-going refinement and understanding of animal models that capture relevant clinical features of neonatal brain injury leading to CP. The potent vasoconstrictor peptide, Endothelin-1 (ET-1), has previously been utilised in animal models to reduce local blood flow to levels that mimic ischemic stroke. Our previous work in this area has shown that it is an effective and technically simple approach for modelling ischemic injury at very early neonatal ages, resulting in stable deficits in motor function. Here, we aimed to extend this model to also examine the impact on cognitive function. We show that focal delivery of ET-1 to the cortex of Sprague Dawley rats on postnatal day 0 (P0) resulted in impaired learning in a touchscreen-based test of visual discrimination and correlated with important clinical features of CP including damage to large white matter structures. 相似文献
10.
锰对低铬白口铸铁组织及硬度的影响 总被引:2,自引:0,他引:2
系统研究了Mn对水平连铸低铬白口铸铁铸态及正火态组织和硬度的影响。结果表明,Mn>2.0%之后对组织有较大影响,由于出现(M+A)组成物,使基体硬度显著提高,这将大大改善了低铬白口铸铁中碳化物与基体硬度的相对关系。试验证实,Mn>3%之后明显改善硬度分布均匀性。还讨论了使低铬锰白口铸铁具有最佳综合性能的合理含Mn量范围 相似文献