Cryocooled Biomagnetometer

描述(由申请人提供)：我们建议研究和确定为低温冷却的多通道大型生物磁性系统开发一种新方法的可行性。机械制冷是唯一一种能够提供冷却大型生物磁性系统所涉及的经济收益的技术。拟议的设计将使这些系统在运行和维护方面更具经济吸引力，并减少与不断处理液氦相关的后勤工作。基于鱿鱼操作的生物磁强计安装一直需要液体冷冻剂 做手术吧。通常，根据系统的类型和检测通道的数量，该操作的成本可能在50万至250万美元之间。因此，一个典型的MEG装置每年将消耗2万至4万美元的液氦。尽管液氦的经济性在过去并不是生物磁性仪器扩散的主要抑制因素，但稀缺性和不断增加的成本可能会改变这一点。机械闭式循环冰箱已经成为使用液体冷冻机的替代方案。这些措施包括降低运营成本、在偏远地区使用和在非垂直方向运行、避免制冷剂输送中断、安全性以及不必每隔几天就转移的便利性。在SQUID中使用闭式循环制冷有两个主要障碍。第一种是(最终)使探测线圈在地球磁场中移动的机械运动。第二个是由于制冷机的冷头和压缩机的活动部件而产生的磁性特征。拟议中的设计可能会显着增加大型生物磁强计系统的市场，不仅在美国，而且尤其是在欧洲和亚洲国家，因为缺乏外国氦气来源，导致相关成本是美国成本的两倍。此外，由于工业需求的增加，氦的短缺正在发展。

DESCRIPTION (provided by applicant): We propose to study and determine the feasibility of developing a novel approach for a cryocooled multichannel large biomagnetic system. Mechanical refrigeration is the only technique capable of providing the economical gains involved in cooling large biomagnetic systems. The proposed design would make these systems more economically attractive to run and maintain as well as reducing the logistics associated with constant handling of liquid helium. Biomagnetometers installations based on SQUID operation have always required liquid cryogens to operate. Typically this operation can run a cost in the range from 0.5 - 2.5 million dollars depending on the type of system and number of detection channels. Thus a typical MEG installation will consume $20,000 -$40,000 of liquid helium annually. While the economics of liquid helium have not been a major inhibitor to the diffusion of biomagnetic instrumentation in the past, scarcity and increasing costs could change that. Mechanical closed cycle refrigerators has become an alternative to the use of liquid cryogens. These include reduction of operating costs, use in remote locations, and operation in non-vertical orientations, avoiding interruptions in cryogen deliveries, safety, and the convenience of not having to transfer every few days. There are two main obstacles to using closed cycle refrigeration with SQUIDs. The first is the mechanical movement that (ultimately) causes the detection coils to move in the Earth's magnetic field. The second is the magnetic signature due to the moving parts of the cryocooler's cold head and compressor. The proposed design could significantly increase the market for large biomagnetometer systems not only in the US but also especially in European and Asian countries because of the lack of foreign helium gas source causing the associated costs to be twice the US costs. In addition, a helium shortage is developing due to increasing demand in industrial.