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51.
从三能级原子在双光子跃迁过程的辐射压力入手,利用其动量扩散系数和阻尼系数,以铷原子为例进行了双光子冷却的理论研究.研究结果表明:三能级原子经过双光子冷却不但可以得到较多普勒极限更低的温度,而且具有较高的冷却效率,此结果可为实验研究提供理论基础. 相似文献
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提出了一种基于高Q光腔中的原子与一行波光场相互作用来制备光场激发相干态和二阶激发相干态的新方法。与已提出的方法比较,该方法具备一些优点:不应用微扰理论且除了最后测量外仅用一步就可完成制备,但该方法成功几率只有50%。 相似文献
55.
Donglai Lu Jun Wang Limin Wang Dan Du Charles Timchalk Richard Barry Yuehe Lin 《Advanced functional materials》2011,21(22):4371-4378
A novel disposable electrochemical immunosensor for highly selective and sensitive detection of organophosphorylated butyrylcholinesterase (OP‐BChE), a specific biomarker for exposure to toxic organophosphorus agents, is presented. In this new approach, zirconia nanoparticles (ZrO2) were employed to selectively capture the OP moiety of OP‐BChE adducts, followed by quantum dot (QD)‐tagged anti‐BChE antibodies for amplified quantification. The captured CdSe‐QD tags can be sensitively detected by stripping voltammetry using an in situ bismuth‐plating method. The OP agent, diisopropylfluorophosphate (DFP), was selected to prepare OP‐BChE adducts in various matrices. The formation of OP‐BChE adducts in plasma sample was confirmed using mass spectroscopy. The developed electrochemical immunosensor demonstrates a highly linear voltammetric response over the range of 0.1 to 30 nM OP‐BChE, with a detection limit of 0.03 nM (based on signal/noise = 3), coupled with a good reproducibility (relative standard deviation 4.5%). Moreover, the immunosensor has been validated with biomonitoring of OP‐BChE adducts in the plasma samples. This novel nanoparticle‐based electrochemical immunosensor thus provides an alternative way for designing a sensitive and cost‐effective sensing platform for on‐site screening/evaluating exposure to a variety of OP agents. 相似文献
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《Ergonomics》2012,55(4):467-473
Abstract Car driving has been studied by combining it with a subsidiary task, performance on which is negatively correlated with the perceptual load imposed by changing conditions of traffic. The present experiment compares a subsidiary task which required almost continuous attention to an auditory display, and which involved memory spans of only 3 sec, with an alternative task which did not require continuous attention, but which involved memory spans of up to 55 sec. The former was found to have some advantages. This comparison was combined with a study of men engaged in 8-hour spells of car driving. Some explanations are offered for the finding that performance on the subsidiary tasks was better at the end of the work-spell than at the beginning. 相似文献
58.
提出了一种新的基于纠缠交换的可验证量子秘密共享协议,秘密分发者与其他参与者进行一对一的信息交互,对某一参与者等概率进入检测模式或信息模式,直至确定信息发送安全后,再与下一参与者进行信息交互。本协议不仅能够避免外部窃听,又可以防止内部欺骗,从而保证共享信息的正确性和安全性,达到可验证的效果。 相似文献
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《Journal of Location Based Services》2013,7(3-4):141-178
ABSTRACTDisclosing the current location of a person can seriously affect their privacy, but many apps request location information to provide location-based services. Simultaneously, these apps provide only crude controls for location privacy settings (sharing all or nothing). There is an ongoing discussion about rights of users regarding their location privacy (e.g. in the context of the General Data Protection Regulation – GDPR). GDPR requires data collectors to notify users about data collection and to provide them with opt-out options. To address these requirements, we propose a set of user interface (UI) controls for fine-grained management of location privacy settings based on privacy theory (Westin), privacy by design principles and general UI design principles. The UI notifies users about the state of location data sharing and provides controls for adjusting location sharing preferences. It addresses three key issues: whom to share location with, when to share it, and where to share it. Results of a user study (N=23) indicate that (1) the proposed interface led to a greater sense of control, that (2) it was usable and well received, and that (3) participants were keen on using it in real life. Our findings can inform the development of interfaces to manage location privacy. 相似文献