The Review of scientific instruments最新文献_第3页

2nd and 3rd order spectral energy corrections with penumbral de-blurring methodology for opacity platform used on the National Ignition Facility. 用半阴影去模糊方法对国家点火装置不透明平台进行二阶和三阶光谱能量校正。

IF 1.6

The Review of scientific instruments Pub Date : 2022-11-01 DOI: 10.1063/5.0101833

E C Dutra, J Emig, C J Fontes, R F Heeter, Y P Opachich, H F Robey, M S Wallace, T S Perry

{"title":"2nd and 3rd order spectral energy corrections with penumbral de-blurring methodology for opacity platform used on the National Ignition Facility.","authors":"E C Dutra, J Emig, C J Fontes, R F Heeter, Y P Opachich, H F Robey, M S Wallace, T S Perry","doi":"10.1063/5.0101833","DOIUrl":"https://doi.org/10.1063/5.0101833","url":null,"abstract":"The Opacity Spectrometer (OpSpec) used in the National Ignition Facility's opacity experiments measures x-ray spectra from 0.9 to 2.1 keV from the different experimental regions: the backlight source, emission source, and the absorption region with the transmission calculated from these regions. The OpSpec designs have gone through several iterations to help improve the signal-to-noise ratio, remove alternate crystal plane reflections, and improve spectral resolution, which helps to increase the validity of the opacity measurements. However, the source spans well outside the current working spectral range, and higher-order reflections are intrinsic to the crystal, which increases the overall signal seen in the data regions. The recorded data are the convolution of 1st order transmission, higher-order reflections, and the penumbra blurring. This work represents the details for deconvolving the 2nd and 3rd order spectral energy corrections with a penumbral de-blurring to correct the relative measurement of x-ray intensity of different spectral energies and further analysis of datasets relevant to the opacity experiments.","PeriodicalId":519534,"journal":{"name":"The Review of scientific instruments","volume":" ","pages":"113527"},"PeriodicalIF":1.6,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40548165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Passive dual-probe near-field microscopy. 被动双探头近场显微镜。

IF 1.6

The Review of scientific instruments Pub Date : 2022-11-01 DOI: 10.1063/5.0116419

R Sakuma, Y Nagai, H Nakajima, K-T Lin, Y Kajihara

引用次数: 0

Outer layer scintillating fiber for low-energy β-ray detection. 用于低能β射线探测的外层闪烁光纤。

IF 1.6

The Review of scientific instruments Pub Date : 2022-11-01 DOI: 10.1063/5.0121557

Sho Toyama, Shigeo Matsuyama, Misako Miwa, Masashi Akari, Katsuhiro Fujita

引用次数: 1

Publisher's Note: "Fiber-tip endoscope for optical and microwave control" [Rev. Sci. Instrum. 93, 095104 (2022)]. 出版人注:“用于光学和微波控制的光纤尖端内窥镜”[Sci修订版]。仪器仪表，1999,095104 (2022)[j]。

IF 1.6

The Review of scientific instruments Pub Date : 2022-11-01 DOI: 10.1063/5.0130260

Stefan Dix, Jonas Gutsche, Erik Waller, Georg von Freymann, Artur Widera

引用次数: 0

Analysis and fabrication of a small-scale radio-frequency balun for magnetic resonance imaging amplifier. 磁共振成像放大器用小型射频平衡器的分析与制造。

IF 1.6

The Review of scientific instruments Pub Date : 2022-11-01 DOI: 10.1063/5.0095045

Yingliang Li, Shouhua Luo, Chunyi Liu, Yuanyuan Ye

{"title":"Analysis and fabrication of a small-scale radio-frequency balun for magnetic resonance imaging amplifier.","authors":"Yingliang Li, Shouhua Luo, Chunyi Liu, Yuanyuan Ye","doi":"10.1063/5.0095045","DOIUrl":"https://doi.org/10.1063/5.0095045","url":null,"abstract":"In this study, the authors report the design and fabrication of a small mixed-integrated balun for magnetic resonance imaging (MRI). The device was designed by using the positive anti-symmetric coupling method, which applies the lump surface-mount technology capacitors as well as mirror-symmetric coupling strips that were etched on the top and bottom layers of a printed circuit board. The capacitors reduced the length of the coupling strips and compensated for imbalances in the phase and gain due to errors in the fabrication process. The structure and equivalent even-odd circuit model of the device was modeled and examined using commercial software to optimize the design parameters. Following this, the device was fabricated and its performance was assessed through measurements using a network analyzer. The results showed that imbalances in the gain and phase were lower than 0.1 dB and 1°, respectively, and the insertion loss and the input voltage standing-wave ratio (VSWR) were lower than 0.4 dB and -25 dB, respectively. More importantly, the device was small, with dimensions of 50 × 60 × 1.5 mm. This makes it suitable for MRI applications involving highly integrated miniaturized systems. The proposed device was integrated into a 3.0 T radio-frequency power amplifier (RFPA) and reduced the dimensions of its power modules by 20% compared with the traditional balun. Finally, the RFPA module was used in an 3.0T MRI system for imaging experiments, and the results showed that the balun can help obtain high-quality scanning images.","PeriodicalId":519534,"journal":{"name":"The Review of scientific instruments","volume":" ","pages":"114711"},"PeriodicalIF":1.6,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40549156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Laser-assisted local metal-organic vapor phase epitaxy. 激光辅助局部金属有机气相外延。

IF 1.6

The Review of scientific instruments Pub Date : 2022-11-01 DOI: 10.1063/5.0092251

Max Trippel, Jürgen Bläsing, Matthias Wieneke, Armin Dadgar, Gordon Schmidt, Frank Bertram, Jürgen Christen, André Strittmatter

{"title":"Laser-assisted local metal-organic vapor phase epitaxy.","authors":"Max Trippel, Jürgen Bläsing, Matthias Wieneke, Armin Dadgar, Gordon Schmidt, Frank Bertram, Jürgen Christen, André Strittmatter","doi":"10.1063/5.0092251","DOIUrl":"https://doi.org/10.1063/5.0092251","url":null,"abstract":"Selective area epitaxial growth is an important technique, both for monolithic device integration as well as for defect reduction in heteroepitaxy of crystalline materials on foreign substrates. While surface engineering with masking materials or by surface structuring is an effective means for controlling the location of material growth, as well as for improving crystalline properties of epitaxial layers, the commonly involved integral substrate heating presents a limitation, e.g., due to constraints ofr the thermal budget applicable to existing device structures. As a solution, an epitaxial growth approach using a laser source only locally heating the selected growth area, in combination with metal-organic precursors to feed a pyrolithic chemical reaction (also known as metal-organic vapor phase epitaxy, MOVPE), is presented. Without masking or surface structuring, local epitaxial growth of III-V compound semiconductor layers on a 50-1500 µm length-scale, with high structural and optical quality, is demonstrated. We discuss general design rules for reactor chamber, laser heating, temperature measurement, sample manipulation, gas mixing, and distinguish laser-assisted local MOVPE from conventional planar growth for the important compound semiconductor GaAs. Surface de-oxidation prior to growth is mandatory to realize smooth island surfaces. Linear growth rates in the range 0.5-9 µm/h are demonstrated. With increasing island diameter, the probability for plastic deformation within the island increases, depending on reactor pressure. A step-flow mode on the island surface can be achieved by establishing a sufficiently small temperature gradient across the island.","PeriodicalId":519534,"journal":{"name":"The Review of scientific instruments","volume":" ","pages":"113904"},"PeriodicalIF":1.6,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40558026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","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 Pa_α line from pellet ablation cloud in Heliotron J. Heliotron J中球团烧蚀云Paα谱线的测量。

IF 1.6

The Review of scientific instruments Pub Date : 2022-11-01 DOI: 10.1063/5.0101885

A Iwata, S Kado, M Murakumo, T Shikama, G Motojima, A Mori, C Feng, H Okada, T Minami, S Ohshima, S Kobayashi, A Ishizawa, Y Nakamura, S Konoshima, T Mizuuchi, K Nagasaki

引用次数: 0

In situ infrared spectroscopy depth profilometer for organic thin films. 有机薄膜原位红外光谱深度轮廓仪。

IF 1.6

The Review of scientific instruments Pub Date : 2022-11-01 DOI: 10.1063/5.0098346

Yixin Ran, Jinde Yu, Fan Cao, Jifa Yu, Laju Bu, Guanghao Lu

{"title":"In situ infrared spectroscopy depth profilometer for organic thin films.","authors":"Yixin Ran, Jinde Yu, Fan Cao, Jifa Yu, Laju Bu, Guanghao Lu","doi":"10.1063/5.0098346","DOIUrl":"https://doi.org/10.1063/5.0098346","url":null,"abstract":"Organic films are widely used in organic optoelectronics due to their flexibility, low-cost fabrication, and ability to be processed over large areas. Typically, the composition of these thin films varies along the film depth direction. In this work, we present a home-developed in situ instrument comprised of a capacitive coupled plasma generator in combination with a Fourier transform infrared spectrometer, to measure the composition distribution along the film-normal direction. During the measurement, the film is sequentially etched by the soft plasma and the evolution of the infrared spectra of the film is in situ monitored by a spectrometer, from which the film-depth-dependent infrared spectra are extracted. The film-depth resolution of this analytical method has been improved to ∼1 nanometer. Thus, it is possible to calculate the composition that varies with depth by utilizing this analysis method. This equipment, which can be applied effectively to the characterization of thin films for both conjugated and unconjugated organic molecules by directly measuring their distinctive molecular vibration signatures, is simple and clear to set up in a large number of laboratories.","PeriodicalId":519534,"journal":{"name":"The Review of scientific instruments","volume":" ","pages":"113901"},"PeriodicalIF":1.6,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40458415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Segmentation of human aorta using 3D nnU-net-oriented deep learning. 基于三维神经网络的深度学习人体主动脉分割。

IF 1.6

The Review of scientific instruments Pub Date : 2022-11-01 DOI: 10.1063/5.0084433

Feng Li, Lianzhong Sun, Kwok-Yan Lam, Songbo Zhang, Zhongming Sun, Bao Peng, Hongzeng Xu, Libo Zhang

{"title":"Segmentation of human aorta using 3D nnU-net-oriented deep learning.","authors":"Feng Li, Lianzhong Sun, Kwok-Yan Lam, Songbo Zhang, Zhongming Sun, Bao Peng, Hongzeng Xu, Libo Zhang","doi":"10.1063/5.0084433","DOIUrl":"https://doi.org/10.1063/5.0084433","url":null,"abstract":"Computed tomography angiography (CTA) has become the main imaging technique for cardiovascular diseases. Before performing the transcatheter aortic valve intervention operation, segmenting images of the aortic sinus and nearby cardiovascular tissue from enhanced images of the human heart is essential for auxiliary diagnosis and guiding doctors to make treatment plans. This paper proposes a nnU-Net (no-new-Net) framework based on deep learning (DL) methods to segment the aorta and the heart tissue near the aortic valve in cardiac CTA images, and verifies its accuracy and effectiveness. A total of 130 sets of cardiac CTA image data (88 training sets, 22 validation sets, and 20 test sets) of different subjects have been used for the study. The advantage of the nnU-Net model is that it can automatically perform preprocessing and data augmentation according to the input image data, can dynamically adjust the network structure and parameter configuration, and has a high model generalization ability. Experimental results show that the DL method based on nnU-Net can accurately and effectively complete the segmentation task of cardiac aorta and cardiac tissue near the root on the cardiac CTA dataset, and achieves an average Dice similarity coefficient of 0.9698 ± 0.0081. The actual inference segmentation effect basically meets the preoperative needs of the clinic. Using the DL method based on the nnU-Net model solves the problems of low accuracy in threshold segmentation, bad segmentation of organs with fuzzy edges, and poor adaptability to different patients' cardiac CTA images. nnU-Net will become an excellent DL technology in cardiac CTA image segmentation tasks.","PeriodicalId":519534,"journal":{"name":"The Review of scientific instruments","volume":" ","pages":"114103"},"PeriodicalIF":1.6,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40549648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Validation of a torsional balance for thrust measurements of Hall effect and microwave-based space propulsion systems. 用于霍尔效应和微波空间推进系统推力测量的扭平衡验证。

IF 1.6

The Review of scientific instruments Pub Date : 2022-11-01 DOI: 10.1063/5.0117584

S Masillo, J Stubbing, K Swar, D Staab, A Garbayo, A Lucca Fabris

{"title":"Validation of a torsional balance for thrust measurements of Hall effect and microwave-based space propulsion systems.","authors":"S Masillo, J Stubbing, K Swar, D Staab, A Garbayo, A Lucca Fabris","doi":"10.1063/5.0117584","DOIUrl":"https://doi.org/10.1063/5.0117584","url":null,"abstract":"A torsional thrust balance has been designed and validated by Surrey Space Centre and Added Value Solutions UK Ltd. in collaboration with the UK Space Agency. The thrust stand has been tested with two electric propulsion (EP) systems operating with xenon: the Halo thruster and the XJET thruster. The first consists of a low-power (<1 kW) Hall effect-based thruster, whose thrust level is between 3 and 20 mN, depending on the power of the system. The second is an electron cyclotron resonance thruster whose operative point is in the 0.3-1.5 mN thrust range. The thruster is mounted on a titanium rotating beam, whose movement is measured by an optical fiber displacement sensor. The thrusters' direct current electrical connections are routed through room temperature liquid metal pots and microwave power is transmitted via a wireless transfer system, minimizing friction effects. To reduce thermal issues during long thruster operations, the torsional thrust balance is designed with a water-cooling hub around the flex pivot. Noise from the laboratory environment is lessened by using four vibration-dampening spring systems as thrust balance feet. The tests on the two EP systems have shown accurate and repeatable results, demonstrating that the balance can be used to characterize different EP systems in the μN-mN thrust range.","PeriodicalId":519534,"journal":{"name":"The Review of scientific instruments","volume":" ","pages":"114501"},"PeriodicalIF":1.6,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40457982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1