Anti-resonance features of destructive quantum interference in single-molecule thiophene junctions achieved by electrochemical gating

基于单个有机分子来构筑电子器件为电子器件微型化提供潜在技术方案。本研究发展了可集成电化学门控的单分子电子器件测试芯片技术和科学仪器方法，在实验和理论两个层面对具有相消量子干涉效应的噻吩衍生物分子器件的电输运过程进行了电化学调控研究，从而首次在室温下实现了对单分子电子器件中量子干涉效应的反共振现象的直接观测和调控，为制备基于量子干涉效应的新型分子材料和器件提供了全新的设计思路和策略。该研究充分展示了电化学调控技术在信息材料和器件领域的重要应用潜力，也体现了我校固体表面物理化学国家重点实验室在电化学研究和科学仪器研发领域的技术积累，以及面向科学前沿开展交叉学科探索的研究特色。 该研究工作是在洪文晶教授、上海电力大学陈文博教授、英国兰卡斯特大学Colin Lambert教授指导下完成的。化学化工学院博士生白杰和李晓慧为论文的共同第一作者，刘俊扬副研究员、师佳副教授、研究生唐永翔、刘帅、黄晓娟、谭志冰和萨本栋微纳研究院的杨杨副教授等也参与了研究工作。田中群教授和毛秉伟教授为该工作提供了重要指导。【Abstract】Controlling the electrical conductance and in particular the occurrence of quantum interference in single-molecule junctions through gating effects, has potential for the realization of high-performance functional molecular devices. In this work, we used an electrochemically-gated, mechanically-controllable break junction technique to tune the electronic behaviour of thiophene-based molecular junctions that show destructive quantum interference (DQI) features. By varying the voltage applied to the electrochemical gate at room temperature, we reached a conductance minimum that provides direct evidence of charge transport controlled by an anti-resonance arising from DQI. Our molecular system enables conductance tuning close to two orders of magnitude within the non-faradaic potential region, which is significantly higher than that achieved with molecules not showing DQI. Our experimental results, interpreted using quantum transport theory, demonstrate that electrochemical gating is a promising strategy for obtaining improved in-situ control over the electrical performance of interference-based molecular devices.This research was supported by the National Key R&D Program of China (2017YFA0204902), National Natural Science Foundation of China (21722305, 21673195, 21503179, 21703188), the Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning, Natural Science Foundation of Shanghai (17ZR1447100), Science and Technology Commission of Shanghai Municipality (14DZ2261000), China Postdoctoral Science Foundation (2017M622060) for funding work in Xiamen. It was also supported by EU Horizon 2020 project QuIET under grant agreement no. 767187EC FP7 ITN ‘MOLESCO’ project no. 606728 and UK EPSRC grants EP/N017188/1 and EP/M014452/1 and Leverhulme Trust (Leverhulme Early Career Fellowships no. ECF-2017-186 and ECF-2018-375) for funding instrumentation used in Lancaster. It was also supported by Hungarian and Czech Academies of Sciences (P2015-107) and Hungarian Research Foundation (OTKA 112034) for funding instrumentation used in Hungary. The authors thank Z.-Q. Tian and B.-W. Mao, Xiamen University, for useful discussions. 该工作获得科技部国家重点研发计划课题（2017YFA0204902），国家自然科学基金委优秀青年科学基金等项目（21722305、21673195、21703188、21503179）以及中国博士后科学基金（2017M622060）等项目的资助，也得到了固体表面物理化学国家重点实验室、能源材料化学协同创新中心的支持

基于程控仪器标准命令的光缆监测系统设计

光缆线路是光纤通信网络的命脉,为了远程实时监测光缆的性能,迅速定位故障点,通过同步数字系列光传输设备提供的以太网接口使用程控仪器标准命令远控光时域反射计,利用LabVIEW设计并实现了光缆远程监测控制软件。实践表明,应用光缆监测系统后,能够减少处理故障所用的人力物力,极大地缩短处理光缆故障的时间

Density clustering algorithm based on real core point

针对目前聚类算法不能有效的处理模糊边界点的问题，提出了一种基于真实核心点的RDBSCAN聚类算法。提出真实核心点的概念，首先在密度聚类过程中的核心点进一步处理分类，把影响聚类效果的伪核心点剔除，将剩下的真实核心点根据密度可达原则进行聚类；然后提出密度合并判定定理：相同类簇内点的真实密度远大于不同类簇的点，以此为指导判断真实核心点的真实密度，使类簇内各点的相似性更大。通过人工数据集与UCI数据集聚类实验看出，RDBSCAN算法降低了模糊边界点的干扰，而且出现了若干新颖的类簇分类，在密度不规则的数据集中聚类更加准确。</p

Interconnection technique between wireless factory automation network and PROFIBUS-DP

阐述基于WIA-FA 的工业无线网络及其与PROFIBUS-DP 网络互联的拓扑结构，分析互联网关的运行机制，设计互联网关的架构，并细化各模块的功能。通过最小和最大响应时间，评估WIA-FA 和PROFIBUS-DP 互联网络的实时性能。物理实验测试结果表明，互联网关能够满足工业控制的实时性要求

TDMA (Time Division Multiple Access) accessing device and TDMA accessing method based on multiple access points

本发明涉及一种基于多接入点的TDMA接入装置及其接入方法。本发明根据现有方法不能同时满足实际工业应用中的实时性和可靠性需求，且存在资源利用率低等问题，充分考虑无线网络的传输特点以及工业自动化应用特点，提出一种基于多接入点的TDMA接入装置及其接入方法。本发明方法的主要思想在于：采用多接入点冗余通信方式以提高系统可靠性；利用多个接入点的信标帧进行时间同步以提高同步精度；针对可靠的接入点回复确认消息以降低重传次数；采用模块化的多接入点装置设计方法以降低装置维护和管理难度

桂枝茯苓丸抗大鼠慢性心衰的实验研究

目的:研究桂枝茯苓丸对异丙肾上腺素诱导大鼠慢性心衰模型的影响,并初步探讨药物对AngⅡ、TGF-β相关因子的影响.方法:健康SD大鼠60只,体重180~220 g,按体质量随机分为6组,即空白对照组、模型对照组、桂枝茯苓丸1.125 g/kg剂量组、桂枝茯苓丸2.25 g/kg剂量组、桂枝茯苓丸4.5 g/kg剂量组和阳性药物对照组(普萘洛尔).建立异丙肾上腺素致大鼠慢性心衰模型,并给予相应药物治疗15 d.末次给药后12 h,麻醉后取血,分别检测血清AST、ALT、CK和LDH水平.取心脏,固定,采用免疫组化方法分别检测心肌TGF-β和AngⅡ的表达水平.结果:与模型对照组相比,桂枝茯苓丸能明显或部分降低ALT的水平(P<0.05~0.01);抑制TGF-β、AngⅡ的表达(P<0.01~0.05).结论:桂枝茯苓丸具有一定的减轻慢性心衰大鼠心肌损伤的作用,其心肌保护机制可能与TGF-β、AngⅡ的降低有关

Sum-Frequency Spectrum Phase Measurement of the Silica-Octadecyltrichlorosilane Interface and Measurement Accuracy Analysis

相位测量和频振动光谱(SFG)可以获得物质表面分子取向等信息,但在实验重复性、实验设计和界面分析等方面仍有一些关键问题没有解决。相位误差会引起光谱变化并误导界面结构分析,因此分析并准确控制误差是相位测量SFG的关键技术。使用z-切石英作为相位标准,测量了修饰在熔融石英基底上的十八烷基三氯硅烷(OTS)在C&mdash;H振动波段的和频振动光谱,对OTS的相位光谱进行了解析,结果表明OTS虚部光谱中, 2 878和2 936 cm~(-1)处的两个正峰分别是末端CH_3的对称振动(CH_3ss)和费米共振(CH_3FR), 2 960 cm~(-1)处的负峰为CH_3的反对称伸缩振动(CH_3as),这三个峰的光谱特征和指认与文献一致。2 910 cm~(-1)附近的负峰为CH_2反对称伸缩(CH_2as),与文献比较,约有20 cm~(-1)的偏移,且在2 850 cm~(-1)附近还观察到一个负峰,归属为CH_2对称伸缩(CH_2ss),分析认为与文献的差异可能是因为样品制备时间影响了OTS的分子排列结构。通过建立OTS虚部谱与CH_3取向角的关系,发现CH_3的三种振动模式的c轴与表面法线的夹角均小于90&deg;,其H更多为向上取向且排列有序,表明相位测量相较于强度测量可以获得更丰富的表面信息。同时,讨论了待测样品和参考样品位置的非一致性对相位测量精度的影响。通过测量OTS在三个不同位置(12.1, 12.3和12.73 mm)的虚部谱,并与模拟相位误差的引入对虚部谱的影响对比,发现待测样品与参考样品测量位置间2.5&mu;m的位移对应于1&deg;的相位误差, 20&deg;相位的偏移会导致零点位置移动约6 cm~(-1),从而引起振动峰位置和符号等的改变,导致对光谱的错误解析。为了获得界面分子稳定可靠的相位信息,需要严格控制两次样品测量位置一致。实验研究结果为提高和频振动光谱相位测量的精度与准确性提供了指导,为界面分子表面态的检测与分析、及微小信号的探测提供了有效手段。</p

Low-overhead time synchronization method based on receivers under start network

本发明涉及工业无线网络技术，具体地说是一种星型网络下基于接收者的低开销时间同步方法。本发明提出的时间同步方法，充分考虑工厂自动化星型无线网络的应用特点，基于IEEE?STD802.11-2007标准以及TDMA机制，利用接收者之间同步的思想，将星型网络中的时钟源设备作为接收者之一，比较时钟源设备的接收时间值与从时钟设备的接收时间值，使从时钟设备获得精准的时间偏差值，此方法消除了传输延迟对时戳数据的影响，实现高效率、低开销前提下的精准时间同步的目标

神经调节素1β通过激活Sirt1信号通路抑制自噬改善大鼠脑缺血再灌注损伤研究 Neuregulin 1β Improves Cerebral Ischemia Reperfusion Injury by Inhibiting Autophagy via Sirt1 Signaling Pathway in Rats

目的 探讨神经调节素1β（neuregulin 1β，NRG1β）是否通过抑制自噬减轻大鼠大脑中动脉缺血再灌注（middle cerebral artery occlusion reperfusion，MCAO/R）损伤，以及对沉默信息调节因子1（silent information regulator protein 1，Sirt1）信号通路的影响。 方法 将210只健康雄性SD大鼠随机分为假手术组（Sham组）、模型组（MCAO/R组）、治疗组（NRG1β组）、激动剂组（SRT501组）、激动剂+治疗组（SRT501+NRG1β组）、抑制剂组（EX527组）和抑制剂+治疗组（EX527+NRG1β组），每组30只。采用改良线栓法建立MCAO/R模型，线栓由颈外动脉插入颈内动脉18～22 mm，堵塞左侧大脑中动脉起始部。缺血2 h后，缓慢拔出线栓，恢复脑血流22 h。EX527（5 mg/kg）、SRT501（100 mg/kg）于术前30 min腹腔注射，NRG1β（2 μg/kg）于拔出线栓后由微量注射器注入颈内动脉。脑缺血2 h、再灌注22 h后采用改良神经损伤严重程度评分（modified neurological severity score，mNSS）法评价各组大鼠的神经行为功能，采用2，3，5-氯化三苯基四氮唑（2，3，5-triphenyltetrazolium chloride，TTC）染色法计算大鼠脑梗死体积比例，苏木精-伊红染色观察神经元形态变化，免疫印迹（western blot，WB）和免疫荧光（immunofluorescence，IF）法分别检测额叶皮质缺血半暗带（ischemic penumbra，IP）区Sirt1、LC3、P62蛋白的表达和阳性细胞指数（positive cell index，PCI）。 结果 NRG1β组大鼠的mNSS[（10.0±0.8）分 vs.（12.8±0.6）分，P<0.001]和脑梗死体积比例[（23.78%±3.52%）vs.（40.24%±1.55%），P<0.001]均优于MCAO/R组，差异具有统计学意义；与MCAO/R组比较，NRG1β组、SRT501组、SRT501+NRG1β组mNSS均有不同程度下降、脑梗死体积比例缩小；各组中SRT501+NRG1β组mNSS最低、脑梗死体积比例最小，EX527组mNSS最高、脑梗死体积比例最大。苏木精-伊红染色显示，NRG1β组大鼠的神经元形态结构损伤较MCAO/R组、EX527组有所改善。WB结果显示，NRG1β组Sirt1表达[（0.81±0.01）vs.（0.67±0.02），P<0.001]和P62表达[（0.92±0.01）vs.（0.78±0.02），P<0.001]均高于MCAO/R组，LC3表达[（0.49±0.02）vs.（0.94±0.03），P<0.001]低于MCAO/R组。IF结果显示，NRG1β组Sirt1 PCI[（0.67±0.01）vs.（0.52±0.02），P<0.001]和P62 PCI[（0.52±0.02）vs.（0.37±0.01），P<0.001]均高于MCAO/R组，LC3 PCI[（0.38±0.01）vs.（0.50±0.01），P<0.001]低于MCAO/R组。WB和IF检测显示，Sirt1与P62表达趋势一致，NRG1β组、SRT501组与SRT501+NRG1β组表达高于MCAO/R组，各组中SRT501+NRG1β组表达最高、EX527组表达最低；LC3蛋白表达趋势与Sirt1、P62相反，在NRG1β组、SRT501组与SRT501+NRG1β组表达较MCAO/R组低；各组中SRT501+NRG1β组表达最低、EX527组表达最高。 结论 NRG1β可通过激活MCAO/R损伤大鼠Sirt1信号通路抑制自噬发挥神经保护作用。 Abstract: Objective To investigate whether neuregulin 1β (NRG1β) can alleviate middle cerebral artery occlusion reperfusion (MCAO/R) injury in rats by inhibiting autophagy, and whether this effect is mediated by the silent information regulator protein 1 (Sirt1) signaling pathway. Methods A total of 210 healthy male SD rats were randomly divided into sham group (sham group), model group (MCAO/R group), treatment group (NRG1β group), agonist group (SRT501 group) and agonist combined with treatment group (SRT501+NRG1β group), inhibitor group (EX527 group) and inhibitor combined with treatment group (EX527+NRG1β group), with 30 rats in each group. The MCAO/R model was established by the modified thread occlusion method to occlude the initial part of middle cerebral artery. After 2 hours of ischemia, cerebral blood flow was restored for 22 hours. EX527 (5 mg/kg) and SRT501 (100 mg/kg) were injected intraperitoneally 30 minutes before surgery, and NRG1β (2 μg/kg) was injected into the internal carotid artery with a microsyringe after restoration of reperfusion. Neurological behavioral function was evaluated by modified neurological severity score (mNSS) at 2 hours after cerebral ischemia and 22 hours after reperfusion. The proportion of cerebral infarction volume in rats was calculated by TTC staining. Morphological changes of neurons were observed by hematoxylin-eosin (HE) staining. The western blot (WB) and immunofluorescence (IF) were used to detect the expression of Sirt1, LC3 and P62 proteins in ischemic penumbra of the frontal cortex. Results The mNSS [(10.0±0.8) vs. (12.8±0.6), P<0.001] and TTC staining results [(23.78%±3.52%) vs. (40.24%±1.55%), P<0.001] in NRG1β group were better than those in MCAO/R group. Compared with MCAO/R group, mNSS in NRG1β group, SRT501 group, SRT501+NRG1β group all decreased in different degree, and the proportion of TTC-stained infarct volume reduced. The mNSS and the proportion of infarct volume were the lowest in SRT501+NRG1β group, while they were the highest in EX527 group among these groups. HE staining showed that the morphological and structural damage of neurons in NRG1β group improved compared with that in MCAO/R group and EX527 group. The WB results showed that the expression of Sirt1 [(0.81±0.01)vs. (0.67±0.02), P<0.001] and P62 [(0.92±0.01) vs. (0.78±0.02), P<0.001] in NRG1β group were higher than those in MCAO/R group, and the LC3 expression [(0.49±0.02) vs. (0.94±0.03), P<0.001] was lower than that in MCAO/R group. The IF results showed that Sirt1 positive cell index (PCI) [(0.67±0.01) vs. (0.52±0.02), P<0.001] and P62 PCI [(0.52±0.02) vs. (0.37±0.01), P<0.001] in NRG1β group were higher than those in MCAO/R group, and LC3 PCI [(0.38±0.01)vs. (0.50±0.01), P<0.001] was lower than that in MCAO/R group. The WB and IF results showed that the expression trend of Sirt1 and P62 was consistent as follows, their expression in NRG1β, SRT501 and SRT501+NRG1β groups were higher than that in MCAO/R group, with the highest expression in SRT501+NRG1β group and the lowest expression in EX527 group; the expression trend of LC3 protein was contrary to that of Sirt1 and P62, and the expression of LC3 protein in NRG1β, SRT501 and SRT501+ NRG1β groups were lower than that in MCAO/R group, with the lowest expression in SRT501+NRG1β group and the highest expression in EX527 group. Conclusions NRG1β plays a neuroprotective role in MCAO/R rats by activating Sirt1 signaling pathway to inhibit autophagy