Sensitive Detection of Carcinoembryonic Antigen Using Stability‐Limited Few‐Layer Black Phosphorus as an Electron Donor and a Reservoir

The instability of few‐layer black phosphorus (FL‐BP) hampers its further applications. Here, it can be demonstrated that the instability of FL‐BP can also be the advantage for application in biosensor. First, gold nanoparticle/FL‐BP (BP‐Au) hybrid is facilely synthesized by mixing Au precursor with FL‐BP. BP‐Au shows outstanding catalytic activity (K = 1120 s^?1 g^?1) and low activation energy (17.53 kJ mol^?1) for reducing 4‐nitrophenol, which is attributed to the electron‐reservoir and electron‐donor properties of FL‐BP, and synergistic interaction of Au nanoparticles and FL‐BP. Oxidation of FL‐BP after catalytic reaction is further confirmed by transmission electron microscope, X‐ray photoelectron spectroscopy, and zeta potentials. Second, the catalytic activity of BP‐Au can be reversibly switched from “inactive” to “active” upon treatment with antibody and antigen in solution, thus providing a versatile platform for label‐free colorimetric detection of biomarkers. The sensor shows a wide detection range (1 pg mL^?1 to –10 µg mL^?1), high sensitivity (0.20 pg mL^?1), and selectivity for detecting carcinoembryonic antigen (CEA). Finally, the biosensor has been used to detect CEA in colon and breast cancer clinical samples with satisfactory results. Therefore, the instability of BP can also be the advantage for application in detecting cancer biomarker in clinic.     

适合小管径空调器的分配器分流性能评价与结构优化

为了开发具有最佳流量分配性能的小管径空调分配器,本文采用数值仿真和空气-水实验相结合的方法评价了常用分配器的分流性能,提出分配器的结构优化方法,并利用空调整机实验验证了该结构优化方法的改进效果。对于三种比较适合于小管径空调器的分配器进行的实验和计算表明,插孔式分配器的分流性能最佳,在额定制冷和额定制热工况下流量分配不均匀度均小于6%;实验结果与仿真计算得出的分配器流量分配不均匀度结果吻合,计算结果与实验的偏差都在15%以内。利用验证过的仿真模型,对插孔式分配器进行结构优化,优化后的分配器应用于空调整机后,系统能效提高了2.2%~2.7%。     

气相法白炭黑填充天然橡胶的裂纹扩展机理

研究了不同粒径,不同份数的白炭黑对天然橡胶(NR)裂纹生长行为的影响。采用具有裂纹生长测试功能的DMA(DMA-Crack Growth)对预割口试样的裂纹扩展速度进行测试。利用超高速显微摄像技术对裂纹扩展尖端进行在线追踪,得到裂纹扩展尖端的动态显微图像。结果表明,添加20 phr原生粒径为15 nm的气相法白炭黑时,裂纹尖端韧带均匀且细密,对裂纹生长起到很好的阻碍作用;添加20 phr原生粒径为7 nm的气相法白炭黑时,对试样的裂纹生长有不利影响。     

电气检测领域电源稳定性核查方法

产品检测中电源具有十分重要的作用,本文以电动机检测实验室为例,介绍了电器领域中电源稳定性的核查方法。     

Analysis of sperm concentration and motility in a microfluidic device

A home-use device that allows rapid and quantitative sperm quality analysis is desirable but not yet fully realized. To aid this effort, this article presents a microfluidic device capable of quantifying sperm quality in terms of two critical fertility-related parameters—motile sperm concentration and motility. The microdevice produces flow field for sperms to swim against, and sperms that overcame the flow within a specified time are propelled along in a separate channel and counted via resistive pulse technique. Data are compared to two control methods clinically utilized for sperm quality exam—hemocytometer and the sperm quality analyzer. Results reveal the numbers of pulses generated by passage of sperms correlates strongly with the two control methods: pulse number from 0 to 335 corresponds to progressively motile sperm concentrations from 0 to 19 × 10⁶/ml (hemocytometer) and Sperm Motility Index from 0 to 204 (sperm quality analyzer). The microdevice should be applicable to facilitate self-assessment of sperm quality at home.     

MSP430单片机的电桥平衡自调节设计

在应变式火炮膛压测试仪中,直流不平衡电桥测量电路是测量火炮膛压信号的核心环节。由于电阻应变计阻值有一定的偏差,使得电桥在初始时达不到平衡,导致测试仪在没有应变时输出信号有为负值的可能性,致使测试仪所测得的数据无法以计算机数值校正方法实现。对于传统的机械电位器,手动调节的方法无法满足应变式火炮膛压测试仪封闭式、小体积的要求。本文设计的MSP430F2002单片机和MAX5402数字电位器所构成的电桥平衡自调节电路,具有结构简单、占用空间小、功耗低、可靠性高等特性,完全符合火炮膛压测试仪的要求。1电桥平衡自调节原理在火炮膛压测试仪中,考虑到测试仪壳体结构的限制以及低功耗的要求,采用的电桥为1/4直     

Side-effect localization for lazy, purely functional languages via aspects

Many side-effecting programming activities, such as profiling and tracing, can be formulated as crosscutting concerns and be framed as side-effecting aspects in the aspect-oriented programming paradigm. The benefit gained from this separation of concerns is particularly evident in purely functional programming, as adding such aspects using techniques such as monadification will generally lead to crosscutting changes. This paper presents an approach to provide side-effecting aspects for lazy purely functional languages in a user transparent fashion. We propose a simple yet direct state manipulation construct for developing side-effecting aspects and devise a systematic monadification scheme to translate the woven code to monadic style purely functional code. Furthermore, we present a static and dynamic semantics of the aspect programs and reason about the correctness of our monadification scheme with respect to them.     

Grid-based collaborative simulation system for vehicle crashworthiness

Globalization and increasing market competition are forcing the automotive industry to develop technology that will enable more efficient collaboration between carmakers and their suppliers. One of the options that can meet this demand is to adopt grid technology in the collaboration process. For the system to be successfully applied, the trust relationship among Virtual Organization (VO) members becomes a very important factor. Systems lacking in secure mechanisms require all the collaborating members to fully trust each other, and thus make their application quite limited. Based on grid technology, this paper proposes a collaborative simulation system for vehicle crash safety design, and discusses the trust relationship among VO members. The grid middleware VEGA and web services working for the collaboration also contribute to the simulation system. Also, a test bed is set up on the basis of the Local Area Network (LAN). At the end of this paper, a real case involving a carmaker and a door supplier is presented to demonstrate how the grid-based collaborative simulation system works.