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1.
Optical imaging has played a pivotal role in deciphering in vivo bioinformatics but is limited by shallow penetration depth and poor imaging performance owing to interfering tissue autofluorescence induced by concurrent photoexcitation. The emergence of near-infrared (NIR) self-luminescence imaging independent of real-time irradiation has timely addressed these problems. There are two main kinds of self-luminescent agents, namely inorganic and organic luminophores. Inorganic luminophores usually suffer from long-term biotoxicity concerns resulting from potential heavy-metal ions leakage and nonbiodegradability, which hinders their further translational application. In contrast, organic luminophores, especially organic semiconducting luminophores (OSLs) with good biodegradable potential, tunable design, and outstanding optical properties, are preferred in biological applications. This review summarizes the recent progress of OSLs used in NIR afterglow, chemiluminescence, and bioluminescence imaging. Molecular manipulation and nanoengineering approaches of OSLs are discussed, with emphasis on strategies that can extend the emission wavelength from visible to NIR range and amplify luminescence signals. This review concludes with a discussion of current challenges and possible solutions of OSLs in the self-luminescence field.  相似文献   
2.
Software is a central component in the modern world and vastly affects the environment’s sustainability. The demand for energy and resource requirements is rising when producing hardware and software units. Literature study reveals that many studies focused on green hardware; however, limited efforts were made in the greenness of software products. Green software products are necessary to solve the issues and problems related to the long-term use of software, especially from a sustainability perspective. Without a proper mechanism for measuring the greenness of a particular software product executed in a specific environment, the mentioned benefits will not be attained. Currently, there are not enough works to address this problem, and the green status of software products is uncertain and unsure. This paper aims to identify the green measurements based on sustainable dimensions in a software product. The second objective is to reveal the relationships between the elements and measurements through empirical study. The study is conducted in two phases. The first phase is the theoretical phase, where the main components, measurements and practices that influence the sustainability of a software product are identified. The second phase is the empirical study that involved 103 respondents in Malaysia investigating current practices of green software in the industrial environment and further identifying the main sustainability dimensions and measurements and their impact on achieving green software products. This study has revealed seven green measurements of software product: Productivity, Usability, Cost Reduction, Employee Support, Energy Efficiency, Resource Efficiency and Tool Support. The relationships are statistically significant, with a significance level of less than 0.01 (p = 0.000). Thus, the hypothesised relationships were all accepted. The contributions of this study revolve around the research perspectives of the measurements to attain a green software product.  相似文献   
3.
In practical applications of structural health monitoring technology, a large number of distributed sensors are usually adopted to monitor the big dimension structures and different kinds of damage. The monitored structures are usually divided into different sub-structures and monitored by different sensor sets. Under this situation, how to manage the distributed sensor set and fuse different methods to obtain a fast and accurate evaluation result is an important problem to be addressed deeply. In the paper, a multi-agent fusion and coordination system is presented to deal with the damage identification for the strain distribution and joint failure in the large structure. Firstly, the monitoring system is adopted to distributedly monitor two kinds of damages, and it self-judges whether the static load happens in the monitored sub-region, and focuses on the static load on the sub-region boundary to obtain the sensor network information with blackboard model. Then, the improved contract net protocol is used to dynamically distribute the damage evaluation module for monitoring two kinds of damage uninterruptedly. Lastly, a reliable assessment for the whole structure is given by combing various heterogeneous classifiers strengths with voting-based fusion. The proposed multi-agent system is illustrated through a large aerospace aluminum plate structure experiment. The result shows that the method can significantly improve the monitoring performance for the large-scale structure.  相似文献   
4.
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   
5.
Copper indium disulfide (CuInS2) thin films as an absorption layer for solar cell and photocatalytic degradation of organic pollutants, were successfully electrodeposited on the FTO coated glass substrate using the simple and inexpensive electrodeposition method and a sulfurization process. The effects of the Cu/In molar ratio, annealing temperature and kind of Cu2+ precursor (Cu(salen) and Cu(acac)2 as novel Cu2+ precursors) on the structural and morphological properties of samples were examined. The XRD diffraction patterns and energy dispersive spectroscopy measurements exhibit that high-quality film with superior crystalline structure was formed in the presence of Cu(salen) as Cu2+ precursor. Also, we found that a suitable heat treatment temperature could suppress the CuS phases and form well-crystallized CIS. As we know, this is the first reported efficiency for any CuInS2 superstrate solar cell to date that fabricated using Cu(salen) as Cu2+ precursor. In addition, the photocatalytic degradation of organic dye in the presence of as-synthesized CuInS2 thin films was studied. The as-prepared semiconductor photocatalysts have a good reusability; it can be successfully reused for 5 times recycling photoactivity tests.  相似文献   
6.
简要介绍了通过IP网络上电路倍增设备(IP CME)的数据流的处理过程;IP CME中的复用技术;控制IP包发送的激活算法;网络发生拥塞丢包的处理方法;并在传输效率和信令处理2个方面与VOIP进行比较,可以看出IP CME具有很大的优越性和良好的发展前景。  相似文献   
7.
1IntroductionSometi mes,noise can i mprove signal transmission orsignal processing in a nonlinear system.This phe-nomenonis the so-called Stochastic Resonance(SR)[1].Most studies of SRinvolve asubthresholdsignal througha single nonlinear systemand the non…  相似文献   
8.
刘芳  郑义 《现代电子技术》2006,29(23):51-53
为了提高入侵检测系统在体系结构上的灵活性、提高入侵检测的速度,本文将Agent技术应用于入侵检测,探讨了基于Agent的入侵检测技术和模型。首先分析了网络安全及入侵检测系统的研究现状及发展趋势,以及入侵检测技术在网络安全中的重要地位和作用。在对入侵检测技术及Agent技术深入分析的基础之上,提出了一种基于Agent的入侵检测系统模型,研究了构成基本构架的各个子系统在整个模型中的作用及相互关系,给出了各自的设计实现方法,并重点讨论了基于Agent的分布式入侵检测系统模型的通信问题。  相似文献   
9.
《Materials Letters》2007,61(11-12):2259-2261
We report the formation of silver nanoclusters of average size ∼ 1.1 nm in a single step ion-exchanged silica glass. Silver clusters are formed in a glass during ion-exchange by fine-tuning the ion-exchange parameters such as salt composition, temperature and time. Such nanocluster formation during ion-exchange preserves the waveguiding properties of the ion-exchanged surface of the glass making them suitable for nonlinear waveguide device fabrication.  相似文献   
10.
Out of Africa     
《Card Technology Today》2006,18(5):14-15
  相似文献   
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