Review of Scientific Instruments最新文献_第9页

Assessment of thermal conductivity in activated carbon adsorbents for liquid nitrogen-based cryo-adsorption vacuum pump applications.

IF 1.3 4区工程技术

Review of Scientific Instruments Pub Date : 2025-03-01 DOI: 10.1063/5.0242242

Abdul Nazer K H, Namitha Venugopal, Hrithik Krishna Raj, Chinnu V K, Pankaj Sagar

{"title":"Assessment of thermal conductivity in activated carbon adsorbents for liquid nitrogen-based cryo-adsorption vacuum pump applications.","authors":"Abdul Nazer K H, Namitha Venugopal, Hrithik Krishna Raj, Chinnu V K, Pankaj Sagar","doi":"10.1063/5.0242242","DOIUrl":"https://doi.org/10.1063/5.0242242","url":null,"abstract":"This paper presents a method for measuring the thermal conductivity of activated carbon adsorbents at liquid nitrogen (LN2) temperature for LN2-based cryo-adsorption vacuum pumps. This method is simple, versatile, and adaptable to various sample geometries of material under evaluation, including powders, spheres, granules, and pellets. This method can also be applied to assess similar materials with thermal conductivity in the range of 0.1-1.5 W/(m K). The thermal conductivity was evaluated by establishing a temperature gradient across the LN2-cooled sample using controlled heat inputs. The measurement accuracy was verified using glassy glycerol whose thermal conductivities at LN2 temperature had already been studied and reported in the literature. The thermal conductivities of activated carbon measured ranged from 0.14 to 0.25 W/(m K) across different sample types and conditions, including forms, packing density, and filler compositions. With an error margin established at 5%, the technique proves both effective and reliable for thermal conductivity measurements at LN2 temperature, offering promising applications in cryogenic engineering, insulation material development, and thermal management systems.","PeriodicalId":21111,"journal":{"name":"Review of Scientific Instruments","volume":"96 3","pages":""},"PeriodicalIF":1.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143711141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Measurement of x-ray bremsstrahlung radiation from high energy electrons by stochastic acceleration in Heliotron J.

IF 1.3 4区工程技术

Review of Scientific Instruments Pub Date : 2025-03-01 DOI: 10.1063/5.0231450

R Yamato, S Kobayashi, T Fujita, K Nagaoka, K Nagasaki, S Inagaki, T Kawate, H Ohgaki, T Kii, H Zen, S Kado, T Minami, H Okada, S Ohshima, S Konoshima, T Mizuuchi, Y Mototake

{"title":"Measurement of x-ray bremsstrahlung radiation from high energy electrons by stochastic acceleration in Heliotron J.","authors":"R Yamato, S Kobayashi, T Fujita, K Nagaoka, K Nagasaki, S Inagaki, T Kawate, H Ohgaki, T Kii, H Zen, S Kado, T Minami, H Okada, S Ohshima, S Konoshima, T Mizuuchi, Y Mototake","doi":"10.1063/5.0231450","DOIUrl":"https://doi.org/10.1063/5.0231450","url":null,"abstract":"A synthetic diagnostic of x-ray bremsstrahlung radiation and a Monte Carlo radiation transport simulation were carried out to obtain the electron energy distribution in stochastic acceleration experiments in Heliotron J, a mid-sized heliotron-type magnetic confinement device. Three sets of LaBr3(Ce) scintillator and photomultiplier tubes were installed in Heliotron J in three directions relative to the magnetic field line, co, counter, and perpendicular, to determine the velocity distribution of the high-energy electrons. These systems are positioned about 5 m away from the vacuum chamber and shielded by lead blocks and magnetic shields to reduce the influence of stray radiation and magnetic fields. The vacuum chamber of Heliotron J is made of stainless steel with a 3D helical shape. Since its x-ray shielding effect is not negligible when obtaining the x-ray energy distribution in the vacuum chamber, the Monte Carlo radiation transport code particle and heavy ion transport code system was applied to Heliotron J to clarify the shielding effect. Given the vacuum chamber and coil shape information and x-ray energy distribution expected in the vacuum chamber, this code can calculate x-ray energy distribution considering the shielding effect of Heliotron J. This simulation model was based on computer aided design data of Heliotron J devices. The x-ray energy distribution in the vacuum vessel was adapted until the simulated and measured x-ray spectra outside the vacuum vessel match with each other. The shapes of resultant distribution have two types of shape: power-law distribution at more than 450 keV and Maxwell distribution at less than 450 keV. At a higher energy range, x-ray bremsstrahlung energy distribution is consistent with the characteristic of stochastic acceleration.","PeriodicalId":21111,"journal":{"name":"Review of Scientific Instruments","volume":"96 3","pages":""},"PeriodicalIF":1.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143711147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A highly optical, controlled trajectory rapid compression and expansion machine for gas phase chemical physics research.

IF 1.3 4区工程技术

Review of Scientific Instruments Pub Date : 2025-03-01 DOI: 10.1063/5.0212259

A C Dhotre, S Biswas

{"title":"A highly optical, controlled trajectory rapid compression and expansion machine for gas phase chemical physics research.","authors":"A C Dhotre, S Biswas","doi":"10.1063/5.0212259","DOIUrl":"https://doi.org/10.1063/5.0212259","url":null,"abstract":"A highly optical Controlled Trajectory Rapid Compression and Expansion Machine (CT-RCEM) has been developed at the University of Minnesota (UMN) for fundamental research in gas phase chemical reaction kinetics, combustion, and high-temperature gas dynamics. Unlike traditional rapid compression machines, UMN CT-RCEM features precise piston motion control using an electrohydraulic actuation system and an active feedback motion controller, allowing digital adjustment of compression ratio, stroke, compression time, and piston trajectory. This innovation eliminates mechanical interventions, enables a higher number of experimental tests in a given time, and offers superior control over the thermodynamic states of the gas mixture under investigation. Equipped with multiple optical windows, including an end-wall, four side-walls, and their variants to accommodate various experimental scenarios, CT-RCEM provides exceptional optical accessibility, enabling fundamental studies utilizing advanced optical and laser diagnostics. Custom-designed UV-grade sapphire windows with specialized seals withstand high combustion temperatures and pressures of up to 250 bar. The optical windows are interchangeable with metal windows, allowing easy integration of equipment such as igniters, injectors, glow plugs, pre-chambers, and sensors. The versatility, functionality, and performance of the CT-RCEM were demonstrated through autoignition experiments with dimethyl ether/air, spark ignition, and optical pre-chamber visualization studies with methane/air. UMN's highly optical CT-RCEM provides a unique platform for gas phase chemical physics research and holds the potential to advance renewable fuels, plasma, and low-emission propulsion alternatives, promoting sustainable energy solutions.","PeriodicalId":21111,"journal":{"name":"Review of Scientific Instruments","volume":"96 3","pages":""},"PeriodicalIF":1.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143664322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Design of a correlation reflectometer radiometer diagnostic and measurements of the electron density-temperature cross-phase angle in the H-mode pedestal with small edge localized modes at ASDEX Upgrade.

IF 1.3 4区工程技术

Review of Scientific Instruments Pub Date : 2025-03-01 DOI: 10.1063/5.0243894

C Yoo, G D Conway, W Burke, P A Molina Cabrera, B Vanovac, R Bielajew, D J Cruz-Zabala, A Silva, A E White

引用次数: 0

Development and evaluation of a bipedal stepping piezoelectric actuator based on stick-slip principle.

IF 1.3 4区工程技术

Review of Scientific Instruments Pub Date : 2025-03-01 DOI: 10.1063/5.0244587

Yue Zhang, Ming Kong, Saijie Mou, Shilin Gu, Lu Liu, Lei Zhu

引用次数: 0

An apparatus for preparing frozen solution samples in ultrahigh vacuum experiments.

IF 1.3 4区工程技术

Review of Scientific Instruments Pub Date : 2025-03-01 DOI: 10.1063/5.0253060

Xinmeng Liu, Jiadong Guo, Jiani Hong, Ying Jiang

引用次数: 0

Development of a helix-based beam position monitor calibration system for sub-relativistic charged-particle beams.

IF 1.3 4区工程技术

Review of Scientific Instruments Pub Date : 2025-03-01 DOI: 10.1063/5.0256290

Minwen Wang, Xin Zhuo, Mingtong Zhao, Maocheng Wang, Yihua Yan, Wenbo Ye, Mengtong Qiu, Zhongming Wang, Rui Zhu

{"title":"Development of a helix-based beam position monitor calibration system for sub-relativistic charged-particle beams.","authors":"Minwen Wang, Xin Zhuo, Mingtong Zhao, Maocheng Wang, Yihua Yan, Wenbo Ye, Mengtong Qiu, Zhongming Wang, Rui Zhu","doi":"10.1063/5.0256290","DOIUrl":"https://doi.org/10.1063/5.0256290","url":null,"abstract":"Accurate calibration of beam position monitor (BPM) responses is a prerequisite for precise beam position measurements. Traditional methods such as the stretched-wire or antenna method can accurately calibrate BPM responses for relativistic beams, but there has been a lack of effective calibration methods for non-relativistic beams, limiting the measurement accuracy of BPMs in low-energy proton or heavy ion linear accelerators. In this study, we developed a BPM calibration platform based on helical slow-wave structures, capable of effectively simulating the electromagnetic fields generated by non-relativistic beams and calibrating the BPM response to these beams. We introduced a period averaging method, which reduces calibration errors caused by impedance mismatches in the helix. We achieved offline calibration of button-type BPMs for non-relativistic beam response characteristics with β as low as 0.122 using this platform. BPM calibration data were compared with simulations and then on-line measurements in the medium beam transport line at the Xi'an Proton Application Facility. Within the central linear response region of the BPM (∼16% of the BPM aperture), the calibrated linear sensitivity of 0.0668 ± 0.0003 is in close agreement with the actual measurement result of 0.0669 ± 0.0009. In the nonlinear response region further from the center, extending to at least 60% of the BPM aperture, the relative measurement error of beam position can be controlled to within 1.2% after calibration. This advance significantly expands the measurement range and enhances the measurement accuracy of BPMs for non-relativistic beams.","PeriodicalId":21111,"journal":{"name":"Review of Scientific Instruments","volume":"96 3","pages":""},"PeriodicalIF":1.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143701373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A multi-channel MRI console for ultra-high field up to 14 T.

IF 1.3 4区工程技术

Review of Scientific Instruments Pub Date : 2025-03-01 DOI: 10.1063/5.0239183

Kaisheng Lin, Miaotian Wang, Yaohui Wang, Hongwei Li, Weimin Wang

{"title":"A multi-channel MRI console for ultra-high field up to 14 T.","authors":"Kaisheng Lin, Miaotian Wang, Yaohui Wang, Hongwei Li, Weimin Wang","doi":"10.1063/5.0239183","DOIUrl":"https://doi.org/10.1063/5.0239183","url":null,"abstract":"Ultra-high field magnetic resonance imaging (MRI) offers significant advantages in terms of signal-to-noise ratio and spatial resolution. In this study, we detail the development of a multi-channel home-built MRI console operating at 14 T. We propose a hybrid analog-digital framework that shifts high-frequency radio frequency transmission and reception issues to lower frequencies, utilizing software-defined radio technology to process these low-frequency signals. Digital pre-emphasis is used in gradient calculations to counteract the effects of eddy currents during gradient switching. Our console can transmit and receive at center frequencies up to 600 MHz. The pulse programmer module achieves a timing resolution of 20 ns, while the transmitter can independently generate waveforms with varying amplitude, frequency, phase, and envelope. The receiver's dual-stage gain control provides 63 dB of adjustable range, optimizing the magnetic resonance (MR) signal's dynamic range. After frequency conversion, the MR signals are digitized with 16-bit resolution and 100 MHz sampling rate. High-resolution water phantom images are acquired on the 14 T Bruker Ascend 600 nuclear magnetic resonance magnet, demonstrating its potential for clinical research and application.","PeriodicalId":21111,"journal":{"name":"Review of Scientific Instruments","volume":"96 3","pages":""},"PeriodicalIF":1.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143573798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

High luminosity inverse geometry inelastic neutron scattering spectrometer at pulsed fast reactor.

IF 1.3 4区工程技术

Review of Scientific Instruments Pub Date : 2025-03-01 DOI: 10.1063/5.0244264

Marta Klepacka, Alexander Belushkin, Evgeny Goremychkin, Dorota Chudoba

引用次数: 0

Application of x-ray fluorescence holography to a single grain in polycrystalline ferroelectric ceramics.

IF 1.3 4区工程技术

Review of Scientific Instruments Pub Date : 2025-03-01 DOI: 10.1063/5.0242691

Ahmed Gadelmawla, Yuta Yamamoto, Koji Kimura, Halubai Sekhar, Naohisa Happo, Kyle G Webber, Tomohiro Matsushita, Hiroo Tajiri, Koichi Hayashi

{"title":"Application of x-ray fluorescence holography to a single grain in polycrystalline ferroelectric ceramics.","authors":"Ahmed Gadelmawla, Yuta Yamamoto, Koji Kimura, Halubai Sekhar, Naohisa Happo, Kyle G Webber, Tomohiro Matsushita, Hiroo Tajiri, Koichi Hayashi","doi":"10.1063/5.0242691","DOIUrl":"https://doi.org/10.1063/5.0242691","url":null,"abstract":"X-ray fluorescence holography (XFH) was, for the first time, applied to a polycrystalline system in order to visualize local structures within a single grain in the system using an x-ray microbeam. XFH was performed on (Ba,Ca)(Zr,Ti)O3 (BCZT) piezoelectric ceramic as the polycrystalline system in the normal mode with a two-dimensional detector. After data acquisition and processing, we obtained a Zr-Kα hologram from the BCZT ceramic. The Kossel lines were clearly observed, which were in good agreement with our simulated results, although there is a possibility that the hologram is contaminated by the signals from other surrounding grains. Furthermore, we confirmed that several atomic images reconstructed from the obtained Zr-Kα hologram can be related to the Ti atoms around Zr in the real space plane. These results clearly demonstrate the applicability of XFH to polycrystalline samples, which significantly expands the potential use of this technique for micro- or mesoscopic research in materials science.","PeriodicalId":21111,"journal":{"name":"Review of Scientific Instruments","volume":"96 3","pages":""},"PeriodicalIF":1.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143650080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0