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991.
建立了一种基于表面等离子体共振(SPR)技术的大肠杆菌特异性快速检测方法。采用EDC/NHS将葡聚糖修饰的CM5芯片表面活化,通过亲和素固定生物素标记的二抗(羊抗兔IgG抗体),利用一抗(兔抗大肠杆菌ATCC25922单克隆抗体)和二抗反应,将兔抗大肠杆菌单克隆抗体固定在传感芯片表面。利用一抗和二抗的质量扩增效应和生物素-亲和素的多级放大效应,实现了对低浓度大肠杆菌ATCC25922的快速检测,提高了SPR传感器灵敏度。利用NaOH溶液对芯片再生,可对多个不同浓度样品进行检测,采用相对响应单位(RU)记录数据。本传感芯片对大肠杆菌ATCC25922响应的线性范围为1.5×102 CFU/mL~1.5×107 CFU/mL,检测限为1.5×102 CFU/mL,相关系数r为0.981 5。这种方法简便快捷,有望成为一种在线检测治病菌的有力手段。 相似文献
992.
随着计算机软硬件技术、计算机网络技术及音视频压缩技术的快速发展,教学方式也面临着一场巨大的变革,各种各样的多媒体教学应用系统应运而生,提高了实际教学工作的效率。为了共享宝贵的教学资源、增强课程学习的灵活性,从实际的教学需求出发,综合运用当前的计算机技术、网络技术以及多媒体技术,提出了一个多媒体教学实时录播系统的设计方案,并针对此设计方案探讨了各种可行的实现方法。 相似文献
993.
《Applied Soft Computing》2008,8(1):734-739
The objective of the study was to improve and validate previously prepared, artificial neural networks (ANNs) based system of high blood pressure risk prediction. Based on simple demographic data system is able to estimate the risk of hypertension. Database for the model construction was obtained from Centers for Disease Control-National Center for Health Statistics (CDC-NCHS). Best generalization results were found to be close to 75%—expressed as the total classification rate. Java applet was designed to be the interface between ANN system and end user. The validation procedure (years 1987–2000) acknowledged above 70% effectiveness of the system. 相似文献
994.
In this paper, a new dynamical network model is introduced, in which the nodes of the network are different. It is shown that by the designed controllers, the state of the network can exponentially synchronize onto a homogeneous stationary state. Some criteria are derived and some examples are presented. The numerical simulations coincide with theoretical analysis. 相似文献
995.
电测井方法所得到信号有一定噪声.若直接分析,往往不能从信号中取出有用的信息,需去噪.小波阈值去噪是常用而重要的方法,其法有赖于选择小波基函数和阈值处理函数.以三次中心B样条小波为基函数,采用改进的软硬阈值处理函数给电测井信号去噪.结果表明,三次中心B样条小波很光滑,去除电测井信号的噪声干扰有效. 相似文献
996.
Xintao Zuo Mengmeng Zhen Dapeng Liu Haohan Yu Xilan Feng Wei Zhou Hua Wang Yu Zhang 《Advanced functional materials》2023,33(15):2214206
The theoretically high-energy-density lithium–sulfur batteries (LSBs) are seriously limited by the disadvantages including the shuttle effect of soluble lithium polysulfides (LiPSs) and the sluggish sulfur redox kinetics, especially for the most difficult solid–solid conversion of Li2S2 to Li2S. Herein, a multifunctional catalytic interlayer to improve the performance of LSBs is tried to introduce, in which Fe1–xS/Fe3C nanoparticles are embedded in the N/S dual-doped carbon network (NSC) composed by nanosheets and nanotubes (the final product is named as FeSC@NSC). The well-designed 3D NSC network endows the interlayer with a satisfactory LiPSs capture-catalytic ability, thus ensuring fast redox reaction kinetics and suppressing LiPSs shuttling. The density functional theory calculations disclose the catalytic mechanisms that FeSC@NSC greatly improves the liquid–solid (LiPSs to Li2S2) conversion and unexpectedly the solid–solid (Li2S2 to Li2S) one. As a result, the LSBs based on the FeSC@NSC interlayer can achieve a high specific capacity of 1118 mAh g−1 at a current density of 0.2 C, and a relatively stable capacity of 415 mAh g−1 at a large current density of 2.0 C after 700 cycles as well as superior rate performance. 相似文献
997.
Mengdi Tian Ze Wang Xing Yuan Heng Zhang Zhixue Liu Yu Liu 《Advanced functional materials》2023,33(22):2300779
Herein, multilevel supramolecular assemblies are reported based on sulfobutylether-β-cyclodextrin (SBE-βCD) and cucurbit[8]uril (CB[8]), which can control the topological morphology from nanoparticles to nanosheets and modulate the multicolor luminescence. Benefiting from the large cavity of CB[8] and its strong binding affinity with positively charged tetraphenylethylene pyridinium (TPE-Py), a 1:2 stoichiometric supramolecular assembly is formed through host–guest interactions with binding constants of 2.95 × 1011 M−2 and fluorescence bathochromic shift about 35 nm due to the macrocyclic confinement effect, thereby endowing the fluorescence enhancement about 20 times when further assembled with negatively charged SBE-βCD to form nanosheets through electrostatic interactions. In contrast, the direct assembly of TPE-Py and SBE-βCD can form nanoparticles through electrostatic interactions, showing only tenfold enhancement and no bathochromic shift due to the lack of macrocyclic confinement effect. After doping the near-infrared dye acceptor sulfonated aluminum phthalocyanine (AlPcS4), the nanosheets structure exhibits a higher energy transfer efficiency of about 75% and a larger antenna effect of 29.3 than that of nanoparticles. The multilevel supramolecular assemblies can be used in multicolor luminescence information storage and multiple logical gate systems, providing an efficient approach for configurationally confined topological morphology regulation and luminescent materials. 相似文献
998.
Wanhai Wang Zhijie Lin Shengzheng Gao Weiguo Zhu Xin Song Weihua Tang 《Advanced functional materials》2023,33(41):2303653
Simplifying solution-processing of bulk-heterojunction (BHJ) organic solar cells (OSCs) via efficient interfacial layers with good generality is in great demand for pushing their large-scale applications. In this study, such a novel and cost-effective self-assembled monolayer (SAM) is reported herein as efficient hole transport layer (HTL) for high efficiency OSCs. The SAM-structured 4-(5,9-dibromo-7H-dibenzo[c,g]carbazol-7-yl)butyl)phosphonic acid (DCB-BPA) enables not only enhanced photon harvesting in the active layer but also minimized nonradiative recombination losses to improve interface charge extraction/transport. As a consequence, high short-circuit current (≈28.07 mA cm−2) is achieved for PM6:BTP-eC9 based OSCs to deliver a champion power conversion efficiency of 18.16%, among the highest values for OSCs using small organic HTLs to date. Importantly, good generality of this SAMs is demonstrated for representative high-efficiency BHJ OSCs systems like PM6:Y6 and PM6:PC61BM, outperforming conventional poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)-based counterparts. Excitingly, the SAM is applicable for large-area HTL processing via immersion method, affording 16.59% efficiency for PM6:BTP-BO-4Cl based OSCs. This study highlights the great potential of engineered SAMs for facile large-scale fabrication of high performance OSCs. 相似文献
999.
1000.
折射率(refractive index, RI)是眼镜镜片的重要参数,影响眼镜镜片的厚度和舒适程度。RI的精确测量,能够为屈光不正患者选择合适的镜片提供指导。本文提出了一种利用频域光学相干层析(optical coherence tomography, OCT)系统测量成型眼镜镜片RI的方法。利用放置镜片前后两次干涉的图样和简单的数据分析计算即可得到待测成型镜片的RI。介绍了使用这种方法的工作原理以及装置,首先对一个K9玻璃材质透镜RI进行测量,结果为1.507(1 310 nm),相对误差不超过2%,以此验证了该方法的合理性、可行性。随后利用此方法对一只成型眼镜镜片进行了测量,得到其RI为1.554(1 310 nm),测量结果的扩展不确定度为0.008 6(k=2)。该方法属于非接触测量,不会对成型镜片造成损坏,操作简便,测量相对误差较低,可基本满足对于成型眼镜镜片RI的测定精度要求。 相似文献