{"title":"A coated piezoelectric crystal detector system with high stability","authors":"K. Pernestål, J. Braun","doi":"10.1016/0250-6874(89)87061-1","DOIUrl":null,"url":null,"abstract":"<div><p>A coated piezoelectric crystal (CPC) detector system with high stability designed for the detection of pollutants in ambient air is described. The system is based on the use of two crystals, which are exposed to the air to be analysed. The incoming air flow is divided into two paths; one is led directly to one of the CPCs and the other flow is connected to a molecular sieve filter that absorbs the pollutants before the flow is led to the other CPC. The flows are controlled by magnetic valves in such a way that one crystal is exposed to either clean air from the molecular sieve filter or to polluted air. The other crystal is exposed in the same way, but in counter phase.</p><p>By careful design and control of the air flows, a high stability is reached and virtually no thermal drift is present. A long-term stability of ±0.002 Hz is demonstrated. The noise sources are analysed and methods to reduce their impact are demonstrated.</p></div>","PeriodicalId":101159,"journal":{"name":"Sensors and Actuators","volume":"19 2","pages":"Pages 85-94"},"PeriodicalIF":0.0000,"publicationDate":"1989-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0250-6874(89)87061-1","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Sensors and Actuators","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0250687489870611","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 1
Abstract
A coated piezoelectric crystal (CPC) detector system with high stability designed for the detection of pollutants in ambient air is described. The system is based on the use of two crystals, which are exposed to the air to be analysed. The incoming air flow is divided into two paths; one is led directly to one of the CPCs and the other flow is connected to a molecular sieve filter that absorbs the pollutants before the flow is led to the other CPC. The flows are controlled by magnetic valves in such a way that one crystal is exposed to either clean air from the molecular sieve filter or to polluted air. The other crystal is exposed in the same way, but in counter phase.
By careful design and control of the air flows, a high stability is reached and virtually no thermal drift is present. A long-term stability of ±0.002 Hz is demonstrated. The noise sources are analysed and methods to reduce their impact are demonstrated.
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
