helium concentration measurement

The developed chromatographic system described her e, can be used for measurements of he-. lium concentrat ion in gr oundwater. The obtained level of helium detection for groundwater. samples of ...

The concentration of helium in tungsten fuzz-like nanostructures has been measured by means of thermal desorption spectroscopy. Fuzz was formed on the W surface under intensive plasma irradiation at 1500 K. ... However, measurements of the He concentration in W fuzz using elastic recoil detection (ERD) method gave only He/ W = …

Helium also exists in concentrations as high as 8 percent in certain natural gases. Most U.S. helium-rich natural gas is located in the Hugoton-Panhandle field in Texas, Oklahoma, and Kansas; the LaBarge field in the Riley Ridge area of Wyoming; and the federal facility in the Cliffside field near Amarillo, Texas . Generally, natural gas ...

replace helium [20–22]. The helium analyser should have a range of about 0–10% helium, a resolution of 0.01% helium or better over the entire range and a 95% res-ponse time of less than 15 s to a 2% step change in he-lium concentration. The meter should be stable (drift of 0.02% or less) for measurement periods of up to 10 min.

Journal Article: Quantitative concentration measurements in a turbulent helium jet using rainbow schlieren deflectometry ... Application of rainbow schlieren deflectometry for concentration measurements in an axisymmetric helium jet. Al-Ammar, K.; Agrawal, A. K.; Gollahalli, S. R.

Helium is present in an average concentration of 0.65 ml/l in water associated with the reservoir; of 7 ml/l in oil and of 100 ml/l in free gas in the reservoir.

If the volume and concentration of helium in the gas mixture rebreathed are known, measurement of the final equilibrium concentration of helium permits calculation of the …

A new capability to not only measure the absolute helium concentration but also measure the 3 He/ 4 He isotopic ratio simultaneously with the H/D/T ratio was commissioned and taken into routine operation. The accuracy limit of the helium concentration can be as good as 0.1 %, but reduces to 0.5–1 % for 4 He in the presence

Objective Measurement of functional residual capacity (FRC) during controlled and especially during assisted ventilation remains a challenge in the physiological evaluation of ventilated patients. To validate a bag-in-box closed helium dilution technique allowing measurements both during pressure-controlled (PCV) and pressure-support …

is 0.001 mbar, and the helium pumping speed of the leak detector is 1.8 L/sec, then the concentration of helium is: He = = 11 ppm 2.0 × 10-8 0.001 × 1.8 × 1 × 10 You can see that even a slight increase in helium concentration, in this case roughly double that normally found in atmosphere, can create a significant leak rate signal that

These measurements provide crucial validation to space weather models, support predictions of peak number density ( ~ 1 cm −3) and the dependence of density …

The simplified helium method for measuring the FRC is described and results obtained in normal and emphysematous subjects are presented. 2. Minute-to-minute changes in helium concentration during the rebreathing period may be plotted against time to represent qualitative changes in intrapulmonary gas mixing. These curves correlate well …

Helium purification system configuration of HTR-PM and radiation monitoring channels for primary coolant. ... In this study, we focused on the design of the activation concentration measurement of gaseous fission products in the primary coolant of HTR-PM using an online gross γ monitoring instrument of nuclear safety class, which can …

crustal rocks.1 The terrestrial atmosphere contains helium with a concentration of 5.24 ppm by volume.2 This is attributable to the balance between the supply from the solid Earth (mantle and crust) and escape from the top of the atmosphere into space.3 Since the residence time of helium in the atmosphere is

Touch Screen Helium Concentration Tester. LACO's LHCT03D Helium Concentration Tester is designed to measure helium concentration in production parts previously filled with helium gas. Working in …

The temperature measurements confirm the expected flame temperatures of approximately 1800, 1630, 1560, and 1530 K for the four pressures, respectively. The decreasing temperature results from an increasing concentration of helium in the air mixture of 0.510, 0.600, 0.635, and 0.650 at 2, 4, 6, and 8 atm, respectively.

We measured the concentration of helium with a katharometer (Godart, response time 0.1 sec), at the expiration port of a Siemens-Elema-900 ventilator. ... An open-circuit helium method for measuring functional residual capacity and defective intrapulmonary gas mixing. J Clin Invest. 1954; 33: 1277-1286. View in Article Scopus (12) ...

Combining earlier measurements of helium at lower dpa levels with knowledge of the 59 Ni behavior we can extrapolate to higher dpa levels since the helium concentration is an excellent retrospective dosimeter of the thermal fluence. Predictions of hydrogen are more difficult, however, due to helium-nucleated cavities storing both …

This is accomplished by applying the quantitative rainbow schlieren deflectometry technique to optically measure the local helium mole percentage across the whole field. Data were acquired over downstream locations extending from tube exit to about 3.0d (d=31.8 or 19.1 mm is the jet tube inside diameter) at spatial resolution of 0.14 …

Dynamic measurement of the helium concentration of evolving tungsten nanostructures using Elastic Recoil Detection during plasma exposure @article{Woller2015DynamicMO, title={Dynamic measurement of the helium concentration of evolving tungsten nanostructures using Elastic Recoil Detection during plasma exposure}, author={Kevin …

shown, helium background in the testing area can greatly affect the ability of the leak detector to successfully find leaks this small. Any helium leak detector in sniffing mode can measure the ambient helium concentration in the test area and also help locate the source of helium contamination. Leak Background Leak Rate 5.00E-09 1.00E-07 1.00E ...

The helium analyser should have a range of ∼0–10% helium, a resolution of ≤0.01% helium over the entire range, and a 95% response time of <15 s to a 2% step change in helium concentration in the breathing circuit. …

Since the standard helium gas is used for the jet experiment, the outlet concentration of the helium jet is the concentration of the standard helium gas. Outside the outlet, due to the action of momentum and buoyancy on the helium, the helium will naturally diffuse in space, and the concentration will decay, showing a hyperbolic law in …

As an illustration we are doing the simple following calculation: for a helium flow rate of 210 NL.min −1 a hydrogen flow rate of 218 NL.min −1 and the 4 mm injection diameter, the ratio of measured helium and hydrogen concentrations should induce a ratio of interface height of 1.09.

Measurements of implanted boron-10 concentration and depth profiles of semiconductor materials in order to calibrate commercial implanters is another application at the UT-NDP facility. The concentration and depth profiles measured with NDP and SIMS are compared with reported data given by various vendors or different implanters …

Helium is present in an average concentration of 0.65 ml/l in water associated with the reservoir; of 7 ml/l in oil and of 100 ml/l in free gas in the reservoir. ... When performing the measurement of the concentration of helium in the surface and make the identification of areas of increased concentrations of gas, it is possible to establish ...

He concentration measurements were carried out using the Dynamics of ION Implantation and Sputtering Of Surfaces (DIONISOS) experiment [8]. Fig. 1 shows a top–down schematic of the measurement set up. Essentially, DIONISOS has the capabilities of ordinary Ion Beam Analysis (IBA) techniques with the added ability to …

There are 2 basic techniques; high vacuum testing which allows leak test thresholds to be set down as low as 1×10 -12 mbar.l.sec -1, or sniffing which is generally used for helium leaks down to 1×10 -6 mbar.l.sec -1. For reference 1 cubic millimetre per second is approximately 1×10 -3 mbar.l.sec -1. or 1cc is approximately 1mbar litre per ...