Na+₋sensing quantum dots for cell-based screening of intracellular Na+ concentrations ([Na+]i)

We have developed a Na-quantum dot (QD) nanosensor for [Na⁺]i measurements. Using this Na-QD, we determined the dynamic physiological responses of [Na⁺]i in nonexcitable human HEK-293F cells and excitable primary rat cardiac myocytes by pharmacologically manipulating the membrane permeability to Na⁺, the Na-K-2Cl cotransporter, and the Na⁺/H⁺ antiporter. These data suggest that the mechanisms of [Na⁺]i homeostasis can now be elucidated with this novel Na-QD nanosensor. This could have a broad impact on Na⁺ channel drug discovery.     

Rating high‐throughput screening results via h‐index

The quantification of both the impact and quality of a scientist's publication record is an essential step in making decisions concerning hiring, promotion, and allocation of funding. In an attempt to resolve this problem, Hirsh proposed the “h‐index,” a single‐number criterion incorporating both the number of publications and the number of citations per publication. This value facilitates rating of a scientist's performance and is now one of the most commonly used matrices. Here, we would like to propose the rating of high‐throughput screening (HTS) result by the h‐index. Rating HTS result is to estimate how the HTS result is preferred by a medicinal chemist. In this study, we applied the h‐index for rating HTS results and observed an enhanced rating of preferred starting points for drug development. In addition, we developed a new index, the maximum common structure (MCS) index, which is more effective than the h‐index. Copyright © 2014 John Wiley & Sons, Ltd.     

Induced current of high temperature superconducting loops by combination of exciting coil and thermal switch

With its commercialization, the second-generation (2G) high temperature superconducting (HTS) RE—Ba—Cu—O (REBCO, RE is rare earth) tape is extensively applied to the superconducting magnets in the high magnetic fields. However, unlike low temperature superconducting (LTS) magnets, the HTS magnet cannot operate in the persistent current mode (PCM) due to the immature superconducting soldering technique. In this paper, an exciting method for two HTS sub-loops, so-called charging and load loops, is proposed by flux pump consisting of exciting coil and controllable thermal switch. Two HTS sub-loops are made of an REBCO tape with two slits. An exciting coil with iron core is located in one sub-loop and is supplied with a triangular waveform current so that magnetic field is generated in another sub-loop. The influence of magnetic flux on induced current in load loop is presented and verified in experiment at 77 K. The relationship between the induced magnetic flux density and the current on the sub-loops having been calibrated, magnetic flux density, and induced current are obtained. The results show that the HTS sub-loops can be excited by a coil with thermal switch and the induced current increases with magnetic flux of exciting coil increasing, which is promising for persistent current operation mode of HTS magnets.     

高温超导电流引线电磁特性及交流损耗研究

在无限长堆叠带材模型的基础上对高温超导电流引线的交流损耗建立了新的计算模型,即正十二边形骨架计算模型.由于正十二边形对称性,通过建立合适的坐标系,对坐标进行旋转即可求出每堆带材处的磁场.使用matlab编程计算并得出一系列电流下的交流损耗值,通过将所得数据绘成图形,比较了不同电流下穿透深度及交流损耗的大小.然后搭建实验平台,测量了不同频率下电流引线的交流损耗,并将理论与实验对比,得到较好的一致性.     

二代高温超导带材耐高温性能研究

通过有限元软件对由20层高温超导带材所制成的超导叠带在覆铝时的温度分布进行模拟,模拟结果表明在覆铝过程中两侧带材均会经历420°C以上的高温.对几种高温超导带材在不同温度和持续时间下,对其ReBCO侧、哈氏合金侧和双侧分别加热进行高温实验,测试得出了各带材临界电流的退化情况.实验结果表明,高温对带材造成了性能退化,不同...     

YBCO高温超导磁体临界电流密度快速确定方法

基于绘图法基本原理,以及YBCO高温超导带材的临界电流特性,采用有限元电磁场分析软件AnsoftMaxwell建立了空心圆柱磁体模型.根据磁场分布、并考虑到带材的临界电流密度随磁场大小和方向的变化关系,给出了影响磁体工作电流特性的磁场的分布.基于以上工作提出了一种利用Ansoft电磁场分析软件快速确定YB-CO高温超导带材临界电流密度的方法.     

高温超导导线在低平行磁场下传输性能的研究及其在电缆应用中的影响

在迄今流行的认知当中,第二代高温超导导线相对于一代导线具有更优良的磁场性能,然而本研究发现在液氮温度和低平行场(平行于导线宽面)的条件下实际情况恰好相反。文中通过测量研究和文献调研相结合,确认了这一现象的可靠性。高温超导电缆在远距离输电和大型城市输电方面都具有显著的性能优势,必将为我国电力能源领域带来重大的技术变革。而在高温超导电缆等应用技术中,低平行场是典型的使用条件,根据本研究得到的数据并考虑到价格因素,目前一代导线在这些应用领域中具有明显的相对优势。     

基于高温超导本征约瑟夫森效应的新型两端恒流器件

我们利用高温超导本征约瑟夫森效应,研制了一种超导薄膜两端恒流器件.恒流器件是将生长在斜切20度LaAlO3基片上的Tl-2212超导薄膜光刻成微桥得到的.对于6μm×8μm的微桥器件,其最高工作电压可达15V以上,当两端电压在1V～11V之间变化时,电流基本稳定在4.3mA,误差不超过±5%,动态内阻大于104 Ω,在最佳工作位置(3V～8V)动态内阻可以达到105 Ω.通过数字模拟,对实际应用中两端恒流器件的rf调制进行了较详细的分析,并可使恒定电流上rf调制小于1%.     

制冷机传导冷却固氮保护的高温超导磁体系统的研究进展

简要的回顾了制冷机传导冷却固氮保护的高温超导磁体系统的发展历史,介绍了此磁体系统的特点,并展望其未来发展趋势。     

液氮温区的小型高频信号检测系统

研究了高温超导约瑟夫逊结的高频信号辐照响应;建立了简便的小型液氮制冷设备,提供79K的工作温度;研究了GPIB仪器控制技术,编写了数据采集软件,利用带有GPIB接口卡的个人电脑以及两个型号为HP34401A的惠普数字多用表,建成一个自动化快速测量系统;利用自动化测量系统测量并研究了高温超导约瑟夫逊结在79K下的直流电流-电压特性曲线以及98GHz高频信号辐照的电压响应和相应的频谱特性。