Search NASA⌕ Search

SEARCH · Search NASA

Results for “INDUCTION”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9

Induction heating cells with cauls over mandrels methods of using thereof

Disclosed herein are induction heating cells and methods of using these cells for processing. An induction heating cell may be used for processing (e.g., consolidating and/or curing a composite layup having a non-planar portion. The induction heating cell comprises a caul, configured to position over and conform to this non-planar portion. Furthermore, the cell comprises a mandrel, configured to position over the caul and force the caul again the surface of the feature. The CTE of the caul may be closer to the CTE of the composite layup than to the CTE of the mandrel. As such, the caul isolates the composite layup from the dimensional changes of the mandrel, driven by temperature fluctuations. At the same time, the caul may conform to the surface of the mandrel, which can be used to define the shape and transfer pressure to the non-planar portion.

Matsen, Marc R.↗

Inductance studies for the Quench Protection system of the Mu2e TS solenoids

This is a preliminary study on the solenoids for the Mu2e experiment. An overview of the Mu2e solenoids is first provided. Then the two solenoid prototypes were tested in the Fermilab Central Helium Liquefying facility. My analysis is focused on measuring and modeling the inductance (self and mutual) of the magnets. This aspect is crucial for Quench Detection Systems and for the control parameters of the power supply driving the magnets. During the first part of my experience at Fermilab, I worked on mathematical mod- els for the magnets to understand their expected behavior. A geometric model based on the Neumann formula was developed and implemented for inductance calculations. This model estimates the inductance (self and mu- tual) of all the Mu2e solenoids. A finite element magnetic model for the two prototype magnets was developed to compare to the results of the geometric model. In the second part of my study I collected measurements on the real Transport Solenoid prototypes. T he solenoids were powered in different configurations in order to identify the circuit model and its parameters. These experiments were first carried on the warm magnets and then on the magnets at a cryo- genic temperature. This allows for a comparison between room temperature and superconducting state.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Design and Performance of the Antenna-Coupled Lumped-Element Kinetic Inductance Detector

Focal plane arrays consisting of low-noise, polarisation-sensitive detectors have made possible the pioneering advances in the study of the cosmic microwave background (CMB). To make further progress, the next generation of CMB experiments (e.g. CMB-S4) will require a substantial increase in the number of detectors compared to current instruments. Arrays of kinetic inductance detectors (KIDs) provide a possible path to realising such large-format arrays owing to their intrinsic multiplexing advantage and relative cryogenic simplicity. In this paper, we report on the design of a variant of the traditional KID design: the antenna-coupled lumped-element KID. A polarisation-sensitive twin-slot antenna placed behind an optimised hemispherical lens couples power onto a thin-film superconducting microstrip line. The power is then guided into the inductive section of an aluminium KID, where it is absorbed and modifies both the resonant frequency and quality factor of the KID. We present the various aspects of the design and preliminary results from the first set of seven-element prototype arrays and compare to the expected modelled performance.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Thermal Kinetic Inductance Detectors for Ground-Based Millimeter-Wave Cosmology

We show measurements of thermal kinetic inductance detectors (TKIDs) intended for millimeter-wave cosmology in the 200–300 GHz atmospheric window. The TKID is a type of bolometer which uses the kinetic inductance of a superconducting resonator to measure the temperature of the thermally isolated bolometer island. We measure bolometer thermal conductance, time constant, and noise equivalent power. We also measure the quality factor of our resonators as the bath temperature varies to show they are limited by effects consistent with coupling to two-level systems.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Development of a Data Acquisition System for Kinetic Inductance Detectors: Wide Dynamic Range and High Sampling Rate for Astronomical Observation

Microwave kinetic inductance detectors have a variety of potential applications in astronomical observations. We built a data acquisition system for kinetic inductance detectors combining a dedicated analog board and a commercially available digital board to meet the requirements of astronomical measurements, such as observation of the cosmic microwave background. This paper reports the status of the development of the data acquisition system. We have already achieved simultaneous readout through 120 channels using a direct down-conversion method to decode the signal. A variety of software has been developed and tested using the functionalities of the system and actual detectors.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Inductive System for Reliable Magnesium Level Detection in a Titanium Reduction Reactor

The determination of the Magnesium level in a Titanium reduction retort by inductive methods is often hampered by the formation of Titanium sponge rings which disturb the propagation of electromagnetic signals between excitation and receiver coils. We present a new method for the reliable identification of the Magnesium level which explicitly takes into account the presence of sponge rings with unknown geometry and conductivity. The inverse problem is solved by a look-up-table method, based on the solution of the inductive forward problems for several tens of thousands parameter combinations.

36 MATERIALS SCIENCE↗

Borna disease virus nucleoprotein inhibits type I interferon induction through the interferon regulatory factor 7 pathway

Highlights: •IRF7 nuclear localisation was inhibited by BDV persistently infected. •BDV N protein resistant to IFN induction both in BDV infected OL cell and N protein plasmid transfected OL cell. •BDV N protein is related to the inhibition of IRF7 nuclear localisation. -- Abstract: The expression of type I interferon (IFN) is one of the most potent innate defences against viral infection in higher vertebrates. Borna disease virus (BDV) establishes persistent, noncytolytic infections in animals and in cultured cells. Early studies have shown that the BDV phosphoprotein can inhibit the activation of type I IFN through the TBK1–IRF3 pathway. The function of the BDV nucleoprotein in the inhibition of IFN activity is not yet clear. In this study, we demonstrated IRF7 activation and increased IFN-α/β expression in a BDV-persistently infected human oligodendroglia cell line following RNA interference-mediated BDV nucleoprotein silencing. Furthermore, we showed that BDV nucleoprotein prevented the nuclear localisation of IRF7 and inhibited endogenous IFN induction by poly(I:C), coxsackie virus B3 and IFN-β. Our findings provide evidence for a previously undescribed mechanism by which the BDV nucleoprotein inhibits type I IFN expression by interfering with the IRF7 pathway.

60 APPLIED LIFE SCIENCES↗

Caffeic acid phenethyl ester inhibits 3-MC-induced CYP1A1 expression through induction of hypoxia-inducible factor-1α

Caffeic acid phenethyl ester (CAPE), a natural component of propolis, is reported to have anticarcinogenic properties, although its precise chemopreventive mechanism remains unclear. In this study, we examined the effects of CAPE on 3-methylcholanthrene (3-MC)-induced CYP1A1 expression and activities. CAPE reduced the formation of the benzo[a]pyrene-DNA adduct. Moreover, CAPE inhibited 3-MC-induced CYP1A1 activity, mRNA expression, protein level, and promoter activity. CAPE treatment also decreased 3-MC-inducible xenobiotic-response element (XRE)-linked luciferase, aryl hydrocarbons receptor (AhR) transactivation and nuclear localization. CAPE induced hypoxia inducible factor-1α (HIF-1α) protein level and HIF-1α responsible element (HRE) transcriptional activity. CAPE-mediated HIF-1α reduced 3-MC-inducible CYP1A1 protein expression. Taken together, CAPE decreases 3-MC-mediated CYP1A1 expression, and this inhibitory response is associated with inhibition of AhR and HIF-1α induction. - Highlights: • CAPE reduced the formation of the benzo[a]pyrene-DNA adduct. • CAPE inhibited 3-MC-induced CYP1A1 expression. • CAPE induced HIF-1α induction. • CAPE-mediated HIF-1α reduced 3-MC-inducible CYP1A1 expression.

3-METHYLCHOLANTHRENE↗

Direct measurements of 3d structure, chemistry and mass density during the induction period of C{sub 3}s hydration

The reasons for the start and end of the induction period of cement hydration remain a topic of controversy. One long-standing hypothesis is that a thin metastable hydrate forming on the surface of cement grains significantly reduces the particle dissolution rate; the eventual disappearance of this layer re-establishes higher dissolution rates at the beginning of the acceleration period. However, the importance, or even the existence, of this metastable layer has been questioned because it cannot be directly detected in most experiments. In this work, a combined analysis using nano-tomography and nano-X-ray fluorescence makes the direct imaging of early hydration products possible. These novel X-ray imaging techniques provide quantitative measurements of 3D structure, chemical composition, and mass density of the hydration products during the induction period. This work does not observe a low density product on the surface of the particle, but does provide insights into the formation of etch pits and the subsequent hydration products that fill them.

36 MATERIALS SCIENCE↗

Focal Radiation Therapy Dose Escalation Improves Overall Survival in Locally Advanced Pancreatic Cancer Patients Receiving Induction Chemotherapy and Consolidative Chemoradiation

Purpose: To review outcomes of locally advanced pancreatic cancer (LAPC) patients treated with dose-escalated intensity modulated radiation therapy (IMRT) with curative intent. Methods and Materials: A total of 200 patients with LAPC were treated with induction chemotherapy followed by chemoradiation between 2006 and 2014. Of these, 47 (24%) having tumors >1 cm from the luminal organs were selected for dose-escalated IMRT (biologically effective dose [BED] >70 Gy) using a simultaneous integrated boost technique, inspiration breath hold, and computed tomographic image guidance. Fractionation was optimized for coverage of gross tumor and luminal organ sparing. A 2- to 5-mm margin around the gross tumor volume was treated using a simultaneous integrated boost with a microscopic dose. Overall survival (OS), recurrence-free survival (RFS), local-regional and distant RFS, and time to local-regional and distant recurrence, calculated from start of chemoradiation, were the outcomes of interest. Results: Median radiation dose was 50.4 Gy (BED = 59.47 Gy) with a concurrent capecitabine-based (86%) regimen. Patients who received BED >70 Gy had a superior OS (17.8 vs 15.0 months, P=.03), which was preserved throughout the follow-up period, with estimated OS rates at 2 years of 36% versus 19% and at 3 years of 31% versus 9% along with improved local-regional RFS (10.2 vs 6.2 months, P=.05) as compared with those receiving BED ≤70 Gy. Degree of gross tumor volume coverage did not seem to affect outcomes. No additional toxicity was observed in the high-dose group. Higher dose (BED) was the only predictor of improved OS on multivariate analysis. Conclusion: Radiation dose escalation during consolidative chemoradiation therapy after induction chemotherapy for LAPC patients improves OS and local-regional RFS.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Comparable Senescence Induction in Three-dimensional Human Cartilage Model by Exposure to Therapeutic Doses of X-rays or C-ions

Purpose: Particle therapy using carbon ions (C-ions) has been successfully used in the treatment of tumors resistant to conventional radiation therapy. However, the potential side effects to healthy cartilage exposed to lower linear energy transfer (LET) ions in the beam track before the tumor have not been evaluated. The aim of the present study was to assess the extent of damage after C-ion irradiation in a 3-dimensional (3D) cartilage model close to human homeostasis. Methods and Materials: Primary human articular chondrocytes from a healthy donor were cultured in a collagen scaffold to construct a physioxic 3D cartilage model. A 2-dimensional (2D) culture was used as a reference. The cells were irradiated with a single dose of a monoenergetic C-ion beam with a LET of approximatively 30 keV/μm. This LET corresponds to the entrance channel of C-ions in the shallow healthy tissues before the spread-out Bragg peak (∼100 keV/μm) during hadron therapy protocols. The same dose of X-rays was used as a reference. Survival, cell death, and senescence assays were performed. Results: As expected, in the 2D culture, C-ions were more efficient than X-rays in reducing cell survival with a relative biological effectiveness of 2.6. This correlated with stronger radiation-induced senescence (two-fold) but not with higher cell death induction. This differential effect was not reflected in the 3D culture. Both ionizing radiation types induced a comparable rate of senescence induction in the 3D model. Conclusions: The greater biological effectiveness of C-ions compared with low LET radiation when evaluated in treatment planning systems might be misevaluated using 2D culture experiments. Radiation-induced senescence is an important factor of potential cartilage attrition. The present data should encourage the scientific community to use relevant models and beams to improve the use of charged particles with better safety for patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Induction ultrafast sintering

This study proposes and demonstrates induction ultrafast sintering (IUS), which enables rapid densification of refractory and other materials via two contactless modalities: direct IUS (d-IUS), where heating occurs through electromagnetic coupling with the sample, and susceptor IUS (s-IUS), where heating is achieved indirectly via an induction-heated metal case. Ultrahigh heating rates of ∼75 to >450 °C/s and temperatures exceeding 2500 °C are readily achieved. Both d-IUS and s-IUS densify molybdenum to high densities within 120 s, with only ∼1–3 % porosity observed by image analysis. Similarly, 3 mol % yttria-stabilized zirconia (3YSZ) reaches ∼97 % relative density in 30 s via s-IUS. This study further demonstrates ultrafast reactive sintering of two difficult-to-sinter materials: a refractory compositionally complex alloy–carbide (RCCA–CCC) composite, NbMoTaW–(Nb 0.37 Mo 0.11 Ta 0.39 W 0.13 ) 2 C, using d-IUS, and a compositionally complex silicide (CCS), (Mo 1/3 Nb 1/3 Zr 1/3 )Si 2 , using s-IUS. This IUS platform offers a versatile route for high-throughput materials discovery and energy-efficient fabrication of bulk refractory materials.

36 MATERIALS SCIENCE↗

Determination of phosphorus and sulfur in uranium ore concentrates by triple quadrupole inductively coupled plasma mass spectrometry

The analysis of impurities in a uranium ore concentrate (UOC) could provide information regarding the source, production history, and potential intended use of the UOC. This study involves the analysis of UOC samples for phosphorus and sulfur. Here, concentrations were determined by triple quadrupole inductively coupled plasma – mass spectrometry and compared with results from a pyrohydrolysis method as well as previously reported results. The sulfur and phosphorus concentrations, determined by the mass spectrometer, were used to explore possible trends in a series of UOC material, and the uncertainties were calculated using GUM workbench software. The triple quadrupole inductively coupled plasma – mass spectrometer method allows for the removal of interferences in the analysis of species.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗

Histone deacetylase inhibitor valproic acid promotes the induction of pluripotency in mouse fibroblasts by suppressing reprogramming-induced senescence stress

Histone deacetylase inhibitor valproic acid (VPA) has been used to increase the reprogramming efficiency of induced pluripotent stem cell (iPSC) from somatic cells, yet the specific molecular mechanisms underlying this effect is unknown. Here, we demonstrate that reprogramming with lentiviruses carrying the iPSC-inducing factors (Oct4-Sox2-Klf4-cMyc, OSKM) caused senescence in mouse fibroblasts, establishing a stress barrier for cell reprogramming. Administration of VPA protected cells from reprogramming-induced senescent stress. Using an in vitro pre-mature senescence model, we found that VPA treatment increased cell proliferation and inhibited apoptosis through the suppression of the p16/p21 pathway. In addition, VPA also inhibited the G2/M phase blockage derived from the senescence stress. These findings highlight the role of VPA in breaking the cell senescence barrier required for the induction of pluripotency. - Highlights: • Histone deacetylase inhibitor valproic acid enhances iPSC induction. • Valproic acid suppresses reprogramming-induced senescence stress. • Valproic acid downregulates the p16/p21 pathway in reprogramming. • This study demonstrates a new mechanistic role of valproic acid in enhancing reprogramming.

60 APPLIED LIFE SCIENCES↗

Determination of the inductance of imploding wire array Z-pinches using measurements of load voltage

The inductance of imploding cylindrical wire array z-pinches has been determined from measurements of load voltage and current. A thorough analysis method is presented that explains how the load voltage of interest is found from raw signals obtained using a resistive voltage divider. This method is applied to voltage data obtained during z-pinch experiments carried out on the MAGPIE facility (1.4 MA, 240 ns rise-time) in order to calculate the load inductance and thereafter the radial trajectory of the effective current sheath during the snowplough implosion. Voltage and current are monitored very close to the load, allowing these calculations to be carried out without the need for circuit modelling. Measurements give a convergence ratio for the current of between 3.1 and 5.7 at stagnation of the pinch.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Magnetic induction measurements using an all-optical {sup 87}Rb atomic magnetometer

In this work we propose, and experimentally demonstrate, the use of a self-oscillating all-optical atomic magnetometer for magnetic induction measurements. Given the potential for miniaturization of atomic magnetometers, and their extreme sensitivity, the present work shows that atomic magnetometers may play a key role in the development of instrumentation for magnetic induction tomography.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Inner surface flash-over of insulator of low-inductance high-voltage self-breakdown gas switch and its application

In this paper, the inner surface flash-over of high-voltage self-breakdown switch, which is used as a main switch of pulse modulator, is analyzed in theory by employing the method of distributed element equivalent circuit. Moreover, the field distortion of the switch is simulated by using software. The results of theoretical analysis and simulation by software show that the inner surface flash-over usually starts at the junction points among the stainless steel, insulator, and insulation gas in the switch. A switch with improved structure is designed and fabricated according to the theoretical analysis and simulation results. Several methods to avoid inner surface flash-over are used to improve the structure of switch. In experiment, the inductance of the switch is no more than 100 nH, the working voltage of the switch is about 600 kV, and the output voltage and current of the accelerator is about 500 kV and 50 kA, respectively. And the zero-to-peak rise time of output voltage at matched load is less than 30 ns due to the small inductance of switch. The original switch was broken-down after dozens of experiments, and the improved switch has been worked more than 200 times stably.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Optical induction scheme for assembling nondiffracting aperiodic Vogel spirals

We introduce an experimental approach to realize aperiodic photonic lattices based on multiplexing of nondiffracting Bessel beams. This holographic optical induction scheme takes advantage of the well localized Bessel beam as a basis to assemble two-dimensional photonic lattices. We present the realization of an optically induced two-dimensional golden-angle Vogel spiral lattice, which belongs to the family of deterministic aperiodic structures. With our technique, a very broad class of photonic refractive index landscapes now becomes accessible to optical induction, which could not be realized with established distributed holographic techniques.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗