道路常用温拌改性剂现状与路用性能评价

针对工程使用温拌剂时缺乏明确的参考依据,系统调查了国内外温拌剂应用状况,确定温拌改性技术主要分类以及目前常用温拌剂种类,全面评价了Sasobit、Aspha-min、Evotherm与EC120等4种常用温拌剂对沥青混合料高温性能、低温性能以及水稳定性等路用性能的影响。结果表明:几种温拌剂的降温效果均可达到30℃,Sasobit和EC120温拌剂对沥青混合料高温稳定性均有不同幅度提高,最大提高幅度在30%以上,4种温拌剂对沥青混合料低温性能略有影响,对水稳定性的影响均不大。     

Novel transcatheter aortic heart valves exhibiting excellent hemodynamic performance and low-fouling property

Transcatheter aortic heart valves (TAHVs) have been widely used for aortic valve replacements, with less trauma and lower clinical risk compared with traditional surgical heart valve replacements. In the present study, composites of poly(ethylene glycol) diacrylate (PEGDA) hydrogels and anisotropic high-shrinkage polyethylene terephthalate/polyamide6 (PET-PA6) fabric (PEGDA/PET-PA6) were fabricated as artificial heart valve leaflets. Dynamic mechanical analyses (DMA) indicated that PEGDA/PET-PA6 composites possessed anisotropic mechanical properties (i.e., storage moduli ～23.30 ± 1.36 MPa parallel to the aligned fabric fibers and ～9.68 ± 0.90 MPa perpendicular to the aligned fibers at 1 Hz) that were comparable to aortic valve leaflets. The PEGDA/PET-PA6 composites with smooth surfaces were highly hydrophilic (contact angle ～41.6° ± 3.8°) and had low-fouling properties without platelet adhesion, suggesting a low risk of thrombogenicity when they interacted with blood. Furthermore, transcatheter aortic heart valves were fabricated using nitinol self-expanding frames and PEGDA/PET-PA6 composites as artificial leaflets, which presented excellent hemodynamic performance with a large orifice area (1.75 cm²) and low regurgitation (3.41%), thus meeting the requirements of ISO 5840-3 standard. Therefore, PEGDA/PET-PA6 composites had suitable mechanical properties, good biocompatibility, and low-fouling properties, indicating that they might be used for TAHVs in the future.     

Unique role of non-mercapto groups in thiol-pinning-mediated Ag growth on Au nanoparticles

Owing to the strong affinity of thiols to Au and Ag, they are often employed to modify the surfaces of nanoparticles (NPs). Recently, these strong ligand-interface interactions have been employed to control NP growth, and this technique has emerged as a unique modulation strategy for creating unconventional plasmonic hybrid nanostructures. In these systems, the roles of the non-mercapto components of the thiol molecules and their structures are still unknown. Therefore, we herein present our investigation into this phenomenon. Primary amino (–NH₂) groups in thiols are found to play a key role in regulating growth kinetics, i.e., in accelerating Ag deposition on Au NPs. The–NH₂ groups are thought to bring Ag ions to the particle surface by coordinating to them, and thereby assist their reduction. The effect of molecular structure is non-trivial and thus provides the possibility of selective thiol detection. Based on the dependence of kinetic modulation on the non-mercapto components and molecular structures of molecules, we demonstrate the highly sensitive and specific detection of cysteine (limit of detection: 6 nM) in a mixture of 19 natural amino acids based on Ag growth on Au nanospheres. In addition, based on this modulation effect, we reveal the entrapping of chiral thiols within the growth layer through their plasmonic circular dichroism (PCD) responses. We believe that thiol-based growth regulation has great potential for creating plasmonic nanostructures with novel functionalities.

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Ultrasound-triggered release of sinoporphyrin sodium from liposome-microbubble complexes and its enhanced sonodynamic toxicity in breast cancer

Nano Research - Applying ultrasound (US) to drug delivery and disease therapy is important work. Sonodynamic therapy (SDT)—a comprehensive therapy using US and a sonosensitizer—exhibits...     

基于DSP某高炮随动控制系统设计

针对高炮随动系统的控制精度问题,设计一套基于DSP随动控制系统设计方案,介绍了系统的软硬件;基于CCS3.3开发环境的基础上,对随动控制系统试验台进行在线调试,并根据上位机给出速度与位置目标参数进行实验调试信号,测出实际测量与目标值之间的实时误差,并且对仿真结果进行分析,实验结果表明,系统设计合理,满足各性能指标要求,稳定性能好、具有快速跟踪能力。     

便携式危险气体报警器的研究与设计

通过测定瓦斯的主要成分甲烷的浓度来间接测量瓦斯浓度是解决目前我国煤矿瓦斯事故多发的有效途径;但大多数测定瓦斯浓度的设备具有体积大、难移动的缺点;针对以上情况,基于对MSP430系列单片机超低功耗和片内外设丰富的特点的深入了解和研究,设计了以甲烷为被检测气体,以MSP430F135为微控制器的便携式危险气体报警器;通过它能够实时监测矿井中甲烷的浓度,并在浓度超过报警上限值时启动蜂鸣、闪光和振动为一体的报警功能;其声、光和震动三为一体的报警功能具有鲜明的独创性和重要性。     

综合测试设备自检模拟器的设计与实现

综合测试设备自检模拟器是综合测试设备自检测的配套设备;综合测试设备在测试导弹之前,要先进行综合测试设备自检测;在综合测试设备自检测时,自检模拟器与综合测试设备对接,对综合测试设备综合检测及单项检测的总线接口和非总线接口进行检查,以验证综合测试设备自身的正确性;讨论了综合测试设备自检模拟器的设计与实现,主要探讨了自检模拟器设计、硬件开发、软件开发以及整个自检模拟器工作过程和功能;应用结果表明将该自检模拟器和综合测试设备交联,可以完成综合测试设备的自测试.     

电厂炉水磷酸根分析仪的研制

为了实时、精确地测量电厂锅炉水中磷酸根离子浓度,以Lambert--Beer定律为测量原理,研制了一种高精度磷酸根分析仪;系统采用MSP430F149为核心控制器,包含数据采集模块、存储显示模块、外围控制模块和智能报警模块等,提供数据采集和处理、触摸式人机交互、串口通信、智能报警等功能;仪表重复性测量实验和误差性测量实验的数据表明,仪表能准确的测量磷酸根离子浓度,工作稳定性好,可靠性高,符合电厂检测磷酸根浓度的要求.     

高可靠性远程数据传输系统设计

针对飞行器系统测试设备研制的要求,设计了一种基于LVDS串行/解串器架构的远程数据传输系统;系统包括远程数据传输模块和电流/电压信号转换模块,采用双绞线传输与普通并行线传输相结合的方式,实现远程数据传输的功能;系统采用FPGA作为主控芯片,使用电缆驱动芯片和自适应电缆均衡器来增强双绞线驱动能力,使用电流环信号传输方式代替电压信号传输方式来增加低速信号的抗干扰能力,同时对PCB布板和系统软件做可靠性优化设计,大大提高了该系统在恶劣使用环境下远距离数据传输的可靠性;目前该系统可以在恶劣电磁环境下以176Mbps的单线波特率在47米实验双绞电缆上实现无误码数据传输。     

A relativistic extension of the complex scaling method using oscillator basis functions

We develop the complex scaling method within the relativistic framework by expanding the Dirac spinors in the complete set of eigensolutions of a harmonic oscillator potential, and present the theoretical formalism of describing the discrete bound and resonant states on the same footing. Based on a well established and frequently used model, we demonstrate the utility and applicability of the extended method and examine the stability of the results with respect to the variations of the parameters of the model. Satisfactory agreements are found for all the calculated results in comparison with some other calculations in references. Especially, the present calculation in the nonrelativistic limit gives a consistent result with that in the nonrelativistic calculation.