公开(公告)号：US3898467A

公开(公告)日：1975-08-05

申请号：US45172574

申请日：1974-03-18

Applicant: COMBUSTION ENG

Inventor： SCHUKEI GLEN ELWIN ,  KOWLES JOSEPH EDWARD

IPC: G21C17/02 ,  G01N23/06 ,  G01N23/09 ,  G01T3/00

CPC classification number: G01N23/09

Abstract: An apparatus and method of operation thereof, to continuously monitor and control the neutron absorption properties of chemical shim used in regulating reactivity of a pressurized water nuclear reactor. Coolant-moderator fluid, containing soluble chemical shim with a neutron absorption property is continuously passed through a chamber having at least one neutron detector spaced from a neutron source of known strength. Utilizing the neutron absorptiometery principle, a signal relating to the concentration of the chemical shim in the coolant-moderator is derived. In addition, the temperature of the sample of coolant is obtained and a temperature compensation signal is generated. The signal related to chemical shim concentration is modified by the temperature compensation signal to correct for temperature related effects. The corrected signal is then applied to a readout and alarm device so that constant monitoring of the shim concentration may be accomplished; additionally, the signal may be applied to maintain the concentration of the chemical shim in the coolant-moderator at a desired level.

Abstract translation: 一种操作装置及其方法，用于连续监测和控制用于调节加压水核反应堆反应性的化学垫片的中子吸收性能。 包含具有中子吸收特性的可溶性化学垫片的冷却剂 - 调节剂流体连续通过具有至少一个与已知强度的中子源间隔开的中子探测器的室。 利用中子吸收光学学原理，得出与冷却剂 - 调节剂中的化学垫片的浓度有关的信号。 此外，获得冷却剂样品的温度，并产生温度补偿信号。 与化学垫片浓度相关的信号由温度补偿信号修改，以纠正温度相关的影响。 然后将校正的信号施加到读出和报警装置，从而可以实现对垫片浓度的恒定监测; 此外，可以施加信号以将冷却剂 - 调节剂中的化学垫片的浓度保持在期望的水平。

公开(公告)号：US3794843A

公开(公告)日：1974-02-26

申请号：US3794843D

申请日：1972-12-29

Applicant: OHMART CORP

Inventor： CHEN Y

IPC: G01N23/09 ,  G01N23/02

CPC classification number: G01N23/09

Abstract: A moisture gauge including a radiation source for irradiating with fast neutrons and gamma radiation a bulk substance having moisture contained therein, a detector responsive to gamma radiation which has interacted with a predetermined fractional cross-sectional area of the bulk substance to produce a first electrical signal correlated to the total weight of the bulk substance including contained moisture, and a detector which is responsive to slow neutrons generated by the interaction of fast neutrons and hydrogen atoms of the contained moisture in said predetermined fractional cross-sectional area to produce a second electrical signal correlated to the weight of the moisture contained in the bulk substance. An electrical circuit divides the moisture weight signal and total weight signal to provide an output correlated to the percent by weight of moisture contained in the bulk material. An alternative embodiment of the invention is disclosed which is particularly adapted to provide accurate measurements of the weight percentage moisture of bulk substances containing a relatively high degree of moisture and/or other bulk substances, such as iron or sodium chloride, having a relatively large thermal neutron reaction cross-section. This embodiment includes a first detector responsive to gamma radiation which has been transmitted through a predetermined fractional cross-sectional area of the bulk substance to produce a first electrical signal correlated to the total weight of the bulk substance, including contained moisture, and a second detector which responds to fast neutrons transmitted through the bulk substance in the predetermined fractional cross-sectional area to produce a second electrical signal correlated to the weight of the moisture contained in the bulk substance. These signals are then mathematically processed to provide an output correlated to the percentage by weight of moisture contained in the bulk material, which output is highly accurate notwithstanding the fact that the bulk substance has relatively high moisture content and/or contains material having a relatively large thermal neutron reaction cross-section.

Abstract translation: 一种湿度计，包括用于向快中子和γ辐射照射的辐射源，其中含有水分的散装物质，响应于伽马辐射的检测器，其与本体物质的预定分数横截面积相互作用以产生第一电信号 与包含含水分的本体物质的总重量相关;以及检测器，其对所述预定分数横截面积中所含水分的快中子和氢原子的相互作用产生的缓慢中子作出响应，以产生第二电信号 与散装物质中所含的水分的重量相关。 电路将水分重量信号和总重量信号分开以提供与散装材料中所含的水分重量百分比相关的输出。

公开(公告)号：US3742367A

公开(公告)日：1973-06-26

申请号：US3742367D

申请日：1970-09-22

Applicant: GEN ELECTRIC

Inventor： GROSSMAN L

IPC: G01N23/09 ,  G21C17/06 ,  G01T3/00

CPC classification number: G21C17/06 ,  G01N23/09

Abstract: A method of detecting moisture and reactive gases in assembled nuclear fuel rods is disclosed in which an alloy of zirconium, nickel and titanium is added to the fuel rod. The fuel rod is uniformly heated for a sufficient time to vaporize moisture in the fuel rod enabling reaction between the alloy and the moisture and reactive gases. The presence of reaction products containing hydrogen can be detected by neutron radiography.

公开(公告)号：US3707631A

公开(公告)日：1972-12-26

申请号：US3707631D

申请日：1970-04-02

Applicant: NAT NUCLEAR CORP

Inventor： UNTERMYER SAMUEL

IPC: G01N23/09 ,  G01T3/06 ,  G21C17/06 ,  G01T1/20 ,  G01T3/00

CPC classification number: G01N23/09 ,  G01T3/06 ,  G21C17/06

Abstract: A system for the non-destructive assay of nuclear fuel is disclosed. A scintillating body is positioned near the fissionable fuel species to be assayed. An interrogating beam of low energy neutrons is passed through a moderating material to reduce the neutrons to the thermal or low epi-thermal regions. The moderated interrogating beam penetrates a selected segment of the fuel. Fission of the fissionable species radiates fast neutrons into the scintillating body producing proton recoil in hydrogenous material. These protons produce scintillation events in large sized phosphor grains. Photons from the scintillation events are carried through a transparent light guide to a light detector for counting. The light guide is disclosed as a substantially transparent, non-scintillating polymer surrounded by a light reflecting layer which in turn is covered by a light shield. In a modified form the nuclear fuel to be assayed is positioned in a cavity enclosed by a moderating material with a neutron source and scintillating body radially positioned from the cavity. The scintillating material is arrayed in a series of grooves formed in a transparent light guide connected with a counting device.

Abstract translation: 公开了一种用于核燃料非破坏性测定的系统。 闪烁体位于要测定的可裂变燃料种类附近。 低能中子的询问光束通过调节材料，以将中子减少到热或低外延热区域。 调节型询问光束穿透选定的燃料部分。 可裂变物种的裂变将快中子辐射到闪烁体中，产生氢质物质的质子反冲。 这些质子在大尺寸磷光体颗粒中产生闪烁事件。 来自闪烁事件的光子通过透明光导进行到光检测器进行计数。 光导被公开为由光反射层围绕的基本透明的非闪烁聚合物，光反射层又被遮光罩覆盖。 在经修改的形式中，要测定的核燃料被定位在由具有中子源的中等材料和由空腔径向定位的闪烁体所包围的空腔中。 闪烁材料排列在与计数装置连接的透明导光板中形成的一系列凹槽中。

公开(公告)号：US3699338A

公开(公告)日：1972-10-17

申请号：US3699338D

申请日：1971-08-05

Applicant: ATOMIC ENERGY COMMISSION

Inventor： BAUMANN NORMAN P ,  AHLFELD CHARLES E

IPC: G01N23/09 ,  G21C17/10 ,  G01T3/00

CPC classification number: G01N23/09 ,  G21C17/10

Abstract: A device for monitoring fissile material has a neutron source that oscillates between a location near and a location remote from a neutron detector. The detector is adjacent to suspected fissile material and is shielded by hydrogenous material from the remote location. The detector output is transmitted to analytical instrumentation for determining prompt and delayed neutron count or the phase angle lag between measured neutron flux and the source oscillation. From these determinations, the reactivity of fissile fuel and the concentration of fissile material in deeply subcritical storage facilities can be obtained.

Abstract translation: 用于监测易裂变材料的装置具有在远离中子探测器的位置和位置之间振荡的中子源。 检测器与可疑裂变材料相邻，并被远程位置的含氢材料屏蔽。 检测器输出传输到分析仪器，用于确定中子计数的快速和延迟，或者测量的中子通量与源振荡之间的相位角滞后。 从这些决定中，可以获得裂变燃料的反应性和裂变材料在深亚临界储存设施中的浓度。

公开(公告)号：US3636353A

公开(公告)日：1972-01-18

申请号：US3636353D

申请日：1968-05-13

Applicant: NAT NUCLEAR CORP

Inventor： UNTERMYER SAMUEL

IPC: G01N23/22 ,  G01N23/09 ,  G21C17/06 ,  G01T3/00 ,  G01T3/02

CPC classification number: G21C17/06 ,  G01N23/09

Abstract: Neutrons having energies confined to a range above thermal and below fast are used to interrogate bulk reactor fuel. Prompt and delayed neutron counting of the reaction products is used to obtain an assay of the valuable fissionable species content of the fuel.

公开(公告)号：US3612874A

公开(公告)日：1971-10-12

申请号：US3612874D

申请日：1968-07-16

Applicant: GEN ELECTRIC

Inventor： PORTER CHARLES R

IPC: G01N23/09 ,  G01T3/00

CPC classification number: G01N23/09 ,  Y10S430/154

Abstract: A nondestructive neutron radiographic technique capable of producing improved radiographs of weld joints is disclosed. Lack of contrast in neutron radiographs of two pieces which have been welded together makes resolving fine gaps in the weld difficult. In the disclosed system, one of the two pieces to be welded is doped with a small amount of a material having a high neutron absorption cross section. This provides the desired radiographic contrast and permits the inspection of an entire weld in one radiograph.

公开(公告)号：US3576994A

公开(公告)日：1971-05-04

申请号：US3576994D

申请日：1969-07-14

Applicant: ATOMIC ENERGY COMMISSION

Inventor： PARKS PAUL B ,  BROWN MARK

IPC: G01N23/09 ,  G01T3/00

CPC classification number: G01N23/09

Abstract: An improved method of preparing a neutron radiograph of biological media by first contacting the media with a fluid containing deuterium such as deuterium oxide. The protium in the nonfatty tissue is replaced with deuterium to substantially reduce the neutron capture and scatter within the deuterated tissue. Consequently, the radiolucency of the nonfatty tissue is greatly increased. Deuterium does not significantly replace the protium in the fatty tissue which therefore remains radiopaque in contrast to the radiolucent nonfatty tissue.

公开(公告)号：US3496358A

公开(公告)日：1970-02-17

申请号：US3496358D

申请日：1966-05-06

Applicant: ATOMIC ENERGY AUTHORITY UK

Inventor： BARTON JOHN PENROSE

IPC: G01N23/09 ,  G01T3/00 ,  H01J39/00 ,  H01J39/32

CPC classification number: G01N23/09

公开(公告)号：US3461286A

公开(公告)日：1969-08-12

申请号：US3461286D

申请日：1968-05-23

Applicant: ATOMIC ENERGY COMMISSION

Inventor： JACKSON CHARIES N JR ,  SPEAR WARD G

IPC: G01N23/09 ,  G01N23/12

CPC classification number: G01N23/09