公开(公告)号：US07312439B1

公开(公告)日：2007-12-25

申请号：US10919526

申请日：2004-08-17

Applicant: Payasada Kotrappa ,  Lorin R. Stieff ,  John C. Dempsey

Inventor： Payasada Kotrappa ,  Lorin R. Stieff ,  John C. Dempsey

IPC: G01V5/00

CPC classification number: G01T1/178 ,  G01T1/14 ,  Y10S250/02

Abstract: A new type of radon progeny monitor called an electret radon progeny integrating sampling unit (E-RPISU) using an electret ion chamber to measure radon progeny concentration. A conventional 1 LPM particulate air sampling system is used to collect the radon progeny on a roughly 3.5 cm2 filter that is mounted on a side of an electret ion chamber such that the collected progeny are exposed to the inside of the chamber. Alpha radiation emitted by the progeny collected on the filter ionizes the air in the approximately 220 ml chamber. Ions of opposite polarity collect on the surface of the electret of suitable thickness and reduce its surface voltage. A specially built surface voltmeter is used to measure the electret voltage before and after sampling. The electret voltage drop that occurs during the sampling period is proportional to the time integrated progeny concentration. A similar unit with a screen in the place of filter is used to measure unattached progeny concentration. Another similar unit without filter is used to provide background response to compute net progeny concentration and also to compute radon concentration.

Abstract translation: 一种新型的氡子代监测器，称为驻极体氡子代后处理采集单元（E-RPISU），使用驻极体离子室测量氡后代浓度。 传统的1 LPM颗粒空气采样系统用于收集安装在驻极体离子室一侧的大约3.5cm 2的过滤器上的氡子代，使得所收集的后代暴露于内部 的房间。 收集在过滤器上的子代发射的α辐射使大约220ml的室中的空气离子化。 相反极性的离子聚集在适当厚度的驻极体的表面上并降低其表面电压。 采用特制的表面电压表测量取样前后的驻极体电压。 在采样期间发生的驻极体电压降与时间积分子代浓度成正比。 使用具有过滤器位置的屏幕的类似单元来测量未附着的子代浓度。 另一个没有过滤器的类似单位用于提供背景响应，以计算净后代浓度，并计算氡浓度。

公开(公告)号：US4814608A

公开(公告)日：1989-03-21

申请号：US936239

申请日：1986-12-01

Applicant: John C. Dempsey ,  Payasada Kotrappa

Inventor： John C. Dempsey ,  Payasada Kotrappa

IPC: G01T1/14 ,  G01V5/00 ,  G01T1/00

CPC classification number: G01T1/14 ,  Y10S250/02

Abstract: Radioactive gas, particularly radon, is measured in the subsoil environment by electrostatically charging one or two electrets and placing the electret(s) within a chamber having openings protected by a filter which permits gas to flow through the openings while preventing particles from flowing through the openings. The chamber with the electrostatically charged electret(s) and the detector is placed in a receiver formed within the hollow wall of an elongated probe. Foam cushions surround the chamber and assist in the filtering. An open material, such as steel wool, holds the foam in place and the next lower section of the probe holds the steel wool in place. When sampling is done at only one level, the next lower section is the soil moving nose of the probe. Holes in the side wall near the nose admit subsoil gas into the receiver. When it is desired to sample radioactive gas at several levels, additional sections of the probe have receivers for holding additional chambers and openings near the bottom of each section admit gas into the receivers. After leaving the probe in the soil for a predetermined period, the probe is removed and disassembled. The chamber is removed from the receiver and the surface charge on the detector is measured. Changes in the surface charge are compared with known relations between changes in surface in radioactive decay in the chamber to give amount of radioactive gas that has decayed in the chamber.

Abstract translation: 放射性气体，特别是氡气，在地下环境中通过静电充电一或两个驻极体并将驻极体放置在具有由过滤器保护的开口的室中，其允许气体流过开口，同时防止颗粒流过 开口 具有静电荷的驻极体和检测器的室被放置在形成在细长探针的中空壁内的接收器中。 泡沫垫围绕室并协助进行过滤。 诸如钢丝绒的开放材料将泡沫保持在适当位置，探针的下一个下部将钢丝绒固定在适当位置。 当仅在一个级别进行采样时，下一个下部是探头的土壤移动的鼻子。 在鼻子附近的侧壁上的孔允许底土气体进入接收器。 当需要以几个等级对放射性气体进行采样时，探头的附加部分具有接收器，用于在每个部分的底部附近保持附加的室和开口，以允许气体进入接收器。 将探头放置在土壤中一段预定的时间后，将探头取出并拆卸。 将室从接收器中取出，并测量检测器上的表面电荷。 将表面电荷的变化与室内放射性衰变中表面变化之间的已知关系进行比较，以给出在室中已经衰变的放射性气体的量。

公开(公告)号：US4853536A

公开(公告)日：1989-08-01

申请号：US936240

申请日：1986-12-01

Applicant: John C. Dempsey ,  Payasada Kotrappa

Inventor： John C. Dempsey ,  Payasada Kotrappa

IPC: G01T1/185 ,  H01J47/02

CPC classification number: H01J47/026 ,  G01T1/185 ,  Y10S250/02

Abstract: A small enclosed chamber with an electrostatically charged electret attached to the inner chamber wall. A filtered hole in the chamber permits radon or other radioactive gas to enter by diffusion. Positive or negative ions (depending on the polarity of the electret charge) formed in the chamber air by the decay of the radioactive gas move to and collect on the electret surface by virtue of its electrostatic attraction to ions of opposite polarity. These ions accumulate and cause a measurable reduction in the surface voltage of the electret which reduction is proportional to the time integrated concentration of the radioactive gas in the chamber. The electret surface voltage of the reduction value is used to calculate the average concentration of the radioactive gas during the exposure period. The electret thickness and chamber volume can both be increased to increase the sensitivity of the invention to radioactive gases such as radon, tritium or carbon-14 dioxide or such other radioactive gases.

Abstract translation: 一个带有静电荷的驻极体的小封闭腔室，连接到内腔壁。 腔室中的过滤孔允许氡气或其他放射性气体通过扩散进入。 通过放射性气体的衰减在腔室空气中形成的正离子（或负极离子（取决于驻极体电荷的极性））由于其对相反极性的离子的静电吸引而移动并收集在驻极体表面上。 这些离子累积并导致驻极体的表面电压的可测量的降低，其减小与室中的放射性气体的时间积分浓度成比例。 减少值的驻极体表面电压用于计算曝光期间放射性气体的平均浓度。 两者都可以增加驻极体厚度和室体积，以增加本发明对放射性气体如氡，氚或二氧化碳或其他放射性气体的敏感性。

公开(公告)号：US4992658A

公开(公告)日：1991-02-12

申请号：US409695

申请日：1989-09-20

Applicant: Robert W. Ramsey, Jr. ,  Payasada Kotrappa

Inventor： Robert W. Ramsey, Jr. ,  Payasada Kotrappa

IPC: G01T1/14

CPC classification number: G01T1/14 ,  Y10S250/02

Abstract: An electret ion chamber for monitoring radon comprises a housing having an electret holder and a cover. The cover is attached to a plunger which closes over the electret when the cover is in place and is removed from the electret when the cover is opened. The plunger effectively turns "on" and "off" the radon monitor with the opening and closing of the cap. In very short term and very long term radon monitors, this turn on and off feature is not needed.

Abstract translation: 用于监测氡的驻极体室包括具有驻极体保持器和盖的壳体。 盖子安装在柱塞上，柱塞在盖子就位时封闭在驻极体上，并且当盖子打开时将其从驻极体上取下。 柱塞有效地打开和关闭氡气监测器的“开”和“关”。 在非常短期和非常长期的氡气监测器中，不需要这种打开和关闭功能。

公开(公告)号：USD327121S

公开(公告)日：1992-06-16

申请号：US654972

申请日：1991-02-14

Applicant: Robert W. Ramsey, Jr. ,  Payasada Kotrappa

Designer： Robert W. Ramsey, Jr. ,  Payasada Kotrappa

公开(公告)号：US5055674A

公开(公告)日：1991-10-08

申请号：US386778

申请日：1989-07-31

Applicant: Payasada Kotrappa

Inventor： Payasada Kotrappa

IPC: G01T1/185 ,  H01J47/02

CPC classification number: H01J47/026 ,  G01T1/185 ,  Y10S250/02

Abstract: An electret ion chamber based radon monitor is employed as a method of measuring radium-226 and dissolved radon-222 concentrations in water. The procedure consists of taking a known volume of water and placing it in a container of known volume and determining the equilibrium radon concentration in the air phase above the water using an electret ion chamber radon. The radon concentration in the original water sample is calculated from the radon concentration of the air phase. A detailed theory is proposed and experimental results reported. Given a 200 ml water sample, it is typically possible to measure radon concentration of 160 pCi/l with an accuracy of 10% in a one day measurement. One pCi/l of Ra-226 can be also determined with an accuracy of 10% over a 10 day period.

Abstract translation: 采用基于驻极体离子室的氡监测器作为测量镭-226和溶解氡-222浓度的方法。 该程序包括取已知体积的水并将其置于已知体积的容器中，并使用驻极体离子室氡确定水上方空气相中的平衡氡浓度。 原水样品中的氡浓度由空气相的氡浓度计算。 提出了详细的理论和实验结果。 给出200毫升水样，通常可以在一天的测量中以10％的精度测量160 pCi / l的氡浓度。 也可以在10天内确定10％的精度的一个pCi / l的Ra-226。