共找到 141,423 条论著文献

1、Advances and prospects in nitrides based light-emitting-diodes*Project supported by the National High Technology Research and Development Program of China (No. 2013AA03A101) 2016

摘要:1 online resource Abstract: Due to their low power consumption, long lifetime and high efficiency, nitrides based white light-emitting-diodes (LEDs) have long been considered to be a promising technology for next generation illumination. In this work, we provide a brief review of the development of GaN based LEDs. Some pioneering and significant experiment results of our group and the overview of the recent progress in this field are presented. We hope it can provide some meaningful information for the development of high efficiency GaN based LEDs and solid-state-lighting.
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2、Increased effective reflection and transmission at the GaN-sapphire interface of LEDs grown on patterned sapphire substrates*Project supported by the National High Technology Program of China (No. Y48A040000) and the National High Technology Program of Ch 2016

摘要:1 online resource Abstract: The effect of patterned sapphire substrate (PSS) on the top-surface (P-GaN-surface) and the bottom-surface (sapphire-surface) of the light output power (LOP) of GaN-based LEDs was investigated, in order to study the changes in reflection and transmission of the GaN-sapphire interface. Experimental research and computer simulations were combined to reveal a great enhancement in LOP from either the top or bottom surface of GaN-based LEDs, which are prepared on patterned sapphire substrates (PSS-LEDs). Furthermore, the results were compared to those of the conventional LEDs prepared on the planar sapphire substrates (CSS-LEDs). A detailed theoretical analysis was also presented to further support the explanation for the increase in both the effective reflection and transmission of PSS-GaN interface layers and to explain the causes of increased LOP values. Moreover, the bottom-surface of the PSS-LED chip shows slightly increased light output performance when compared to that of the top-surface. Therefore, the light extraction efficiency (LEE) can be further enhanced by integrating the method of PSS and flip-chip structure design.
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3、A case of Naegleria fowleri related primary amoebic meningoencephalitis in China diagnosed by next-generation sequencing 2018

4、智慧学习 2018/8

5、RES-Scanner:a software package for genome-wide identification of RNA-editing site 2016

6、Exploration of photosensitive polyimide as the modification layer in thin film microcircuit 2018

摘要:1 online resource Abstract: Positive type photosensitive polyimide is used as the modification layer in the thin film transistors production process. The photosensitive polyimide is not only used as the second insulating layer, it can also be used instead of a mask because of the photosensitivity. A suitable curing condition can help photosensitive polyimide form the high performance polyimide with orderly texture inside, and the performance of imidization depends on the precise control of temperature, time, and heat control during the curing process. Therefore, experiments of different stepped up heating tests are made, and the ability of protecting silicon dioxide is analyzed.
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7、Chemical proteomic profiling of protein N-homocysteinylation with a thioester probe1 2018

8、民用水暖煤炉通用技术条件 2018/2

9、Ultrafast growth of horizontal GaN nanowires by HVPE through flipping the substrate1 2018

10、智慧安居应用系统基本功能要求 2018/7

11、智慧安居信息服务资源描述格式 2018/7

12、New digital infrastructure, cross-border e-commerce and global vision of creating electronic World Trade Platform 2018

摘要:The article explores the relationship between technological progress, cross-border e-commerce and the establishment of global digital customs from the dimensions of the latest development of new digital infrastructure, national Single Window system and global vision of creating Electronic World Trade Platform (eWTP). It is argued that cross-border e-commerce platforms, national Single Window and eWTP, all of which are indispensable for the establishment of global digital customs, have close linkages in business regulation, data sharing and information exchange. The establishment of global digital customs requires global governance through the joint efforts by firms, national governments and international organizations.
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13、The dynamic role of small- and medium-sized multinationals in global production networks: Norwegian maritime firms in the Greater Shanghai Region in China 2018

摘要:1 online resource Abstract: This article examines the role of small- and medium-sized multinational enterprises (MNEs) in the dynamic development of global production networks (GPNs) in the maritime industry. It studies the dynamism between subsidiaries of Norwegian maritime firms and regional actors and institutions in the Greater Shanghai Region of China from the perspectives of the subsidiaries. It argues that strategic coupling, recoupling and decoupling are partly the results of regional selection mechanisms. However, in the cases where the subsidiaries are embedded within the host region, the strategies and behaviour of MNEs are of decisive importance for the dynamic development of GPNs.
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14、Anomalous luminescence efficiency enhancement of short-term aged GaN-based blue light-emitting diode 2016

摘要:1 online resource Abstract: The origin of anomalous luminescence efficiency enhancement of short-term aged GaN-based blue light-emitting diodes was studied. We found that the intensity of the electroluminescence and photoluminescence spectra were both increased in the very beginning period of aging. With the help of a rate-equation model, we concluded that this kind of luminescence efficiency enhancement is a joint effect of the defect reduction in active layers and the changes out of active layers, for example the Mg acceptor annealing.
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15、The Determinants of Virtue: Modelling Changes in the CSR Ratings of Chinese Firm 2017

摘要:Most empirical studies on Corporate Social Responsibility (CSR) use cross-sectional data or case studies, making causality hard to establish. We overcome this limitation by using panel data on Chinese firms. We find no effect of last year's profits on CSR ratings, although their negative contemporaneous relation suggests a trade-off. Managerial shareholdings reduce CSR ratings while rising wages and employment are the main drivers of increasing CSR ratings. This suggests the CSR agenda aligns with the interests of labour, but not capital. However, the positive effect of Tobin's Q may indicate CSR is associated with intangibles of value to a firm.
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16、假期时光 2018/6

17、智慧学习 2018/8

18、智慧学习 2018/8

19、Characterization of viral RNA splicing using whole-transcriptome datasets from host specie 2018

20、Evaluation of light extraction efficiency for the light-emitting diodes based on the transfer matrix formalism and ray-tracing method*Project supported by the National Natural Science Foundation of China (Nos.11574306, 61334009), the China International S 2016

摘要:1 online resource Abstract: The internal quantum efficiency (IQE) of the light-emitting diodes can be calculated by the ratio of the external quantum efficiency (EQE) and the light extraction efficiency (LEE). The EQE can be measured experimentally, but the LEE is difficult to calculate due to the complicated LED structures. In this work, a model was established to calculate the LEE by combining the transfer matrix formalism and an in-plane ray tracing method. With the calculated LEE, the IQE was determined and made a good agreement with that obtained by the ABC model and temperature-dependent photoluminescence method. The proposed method makes the determination of the IQE more practical and conventional.
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