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Mg-doped Al 2 O 3 protective layers were deposited on Pt–PtRh 10 (S-type) thin film thermocouples (TFTCs) by reactive magnetron sputtering. The changes in the composition, microstructure, and element distribution of the Mg-doped Al 2 O 3 films before and after annealing at 1200 °C for 3 h were investigated using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). The results indicate that incorporating MgO into Al 2 O 3 as an enhancement phase not only inhibits the crystallization and phase transformation of Al 2 O 3 but also promotes the formation of MgAl 2 O 4 , sequentially further enhancing the material's high-temperature protective properties. The thermoelectric properties of S-type TFTCs with 1.6 μm thick Al 2 O 3 and Mg-doped Al 2 O 3 protective layers were explored, respectively. The results of static calibration at high temperatures demonstrate that the TFTCs with the Mg-doped Al 2 O 3 protective layer can operate at 1148 °C for over 96 h and at 1480 °C for a brief period. Following 4 calibration cycles, compared to the TFTCs with the Al 2 O 3 protective layer, the average Seebeck coefficients of the TFTCs with the Mg-doped Al 2 O 3 protective layer exhibit a slower decline rate, and its drift rate during the 4th cycle is merely 3.28 °C/h. The TFTCs featuring Mg-doped Al 2 O 3 protective layers demonstrate extended lifetimes, superior high-temperature stability, and enhanced reliability when contrasted with those utilizing undoped Al 2 O 3 protective layers. These attributes offer valuable insights into the progression of TFTC technology. [ABSTRACT FROM AUTHOR]

The composition and microstructure of sandwich structure Al 2 O 3 /Si 3 N 4 /YAlO multilayer films deposited by magnetron sputtering were investigated. The results of X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) show that α-SiAlON and Y-doped α-SiAlON are formed at the interface of Al 2 O 3 /Si 3 N 4 and Si 3 N 4 /YAlO respectively after nitrogen annealing at 1300 °C. The thermoelectric properties of S-type (Pt/Pt–10%Rh) thin film thermocouples (TFTCs) with Al 2 O 3 and Al 2 O 3 /Si 3 N 4 /YAlO protective layers deposited by magnetron sputtering were investigated from 700 °C to 1550 °C. The high temperature static calibration results show that the thermoelectric performance of TFTCs with an Al 2 O 3 protective layer begins to decline at 1350 °C, the drift rate of the TFTCs is 13.27 °C/h, and the TFTCs fail at 1550 °C. However, the drift rate of TFTCs with an Al 2 O 3 /Si 3 N 4 /YAlO protective layer is only 2.19 °C/h at 1350 °C, and the performance begins to decline significantly at 1550 °C with a drift rate of 82.89 °C/h. The S-type TFTCs with sandwich structure Al 2 O 3 /Si 3 N 4 /YAlO multilayer provides a good prospect for the application of TFTCs in ultra-high temperature environment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multi-objective optimization framework for enhancing CDQ system efficiency is proposed. • Deep learning surrogate model for system efficiency prediction is developed. • Optimal system efficiency with corresponding operating parameters is identified. • System dynamic characteristics based on optimization results are studied. Coke dry quenching is a promising technology for energy saving and environmental protection in the industrial sectors. Prediction of system efficiency index (SEI) and dynamic adjustment of operating parameters are essential to ensure high system efficiency. In this study, a deep learning-assisted multi-objective optimization framework was proposed to improve coke quenching efficiency and steam production simultaneously. Firstly, numerous on-site process parameters were collected as the data basis for subsequent model construction, and a system-level heat balance model was established and validated for real-time calculation of coke burning loss rate. Then, an attention-based one-dimensional convolutional neural network was developed as a data-driven surrogate model to establish the mapping relationship between the operating parameters and SEI. Finally, the Non-dominated Sorting Genetic Algorithm II was combined with the Technique for Order of Preference by Similarity to Ideal Solution to rapidly identify the optimal operating parameters under different loads. The optimization results also provided a new insight into the system dynamic characteristics. The results show that the surrogate model can swiftly and precisely predict SEI, with R2 exceeding 0.9. Compared with initial operating conditions, the optimal decision scheme has improved SEI by 82 %, with the optimal coke burning loss rate and main steam flow rate of 0.56 % and 83.6 t/h, respectively. This work will provide valuable decision aids for technicians to reach the desired system efficiency. [ABSTRACT FROM AUTHOR]

In this paper, hydrogen ions doping is used to construct lattice defects in AlN thin films. Effects of hydrogen ions doping on the lattice structure, components, and defects of AlN thin films were analyzed. SIMS results show several main types of point defects formed in hydrogen ions doped AlN thin films. XPS spectra find many nitrogen-vacancy defects on the surface of AlN thin films. These point defects make Raman scattered photons fall, thus weakening Raman scattering intensity. High-resolution TEM image shows abundant dislocation defects. Lattice defects produced by hydrogen ions doping make the lattice structure of AlN thin films stretched along the c-axis. The X-ray diffraction peak of the (002) crystal plane of the AlN thin films shifts to the left seriously. The lattice defects caused by hydrogen ions doping are repaired at high temperatures, and then the lattice of the AlN thin films shrinks, which leads to the recovery of the X-ray diffraction peak position. The X-ray diffraction angle increases linearly with temperature and time. The linear variation relationship can be used for temperature interpretation. • Hydrogen ions doped AlN thin film is used as a sensitive material for temperature interpretation. • X-ray diffraction angle of annealed hydrogen ions doped AlN thin film increases linearly with annealing temperature and time. • The relationship between XRD diffraction angle and temperature is used as the basis for temperature interpretation. [ABSTRACT FROM AUTHOR]

Zero drift is one of the important factors affecting the accuracy of hydrogen sensor. To restrain the zero drift, the PdNi nano-film hydrogen sensors were vacuum annealed and effects of different vacuum annealing temperatures on the micro-structure, morphology and hydrogen sensing performances were explored in detail. The results show that with the annealing temperature increasing, the grains grow and the lattice constantly decreases. And the morphology of the surface grains changes from cone to sphere when the annealing temperature is more than 250 °C. Moreover, we provide a concept of EZD (effect of zero drift) to quantitative analysis of the effect of zero drift on hydrogen sensing performance. Repeatability tests reveal that annealing can inhibit EZD when the annealing temperature is more than 150 °C, which is attributed to defects of PdNi nano-film reducing and stability improving. However, increasing annealing temperature leads to the deterioration of sensing performances such as response (Rs), response time (t rs) and recover time (t rc), especially when the annealing temperature is more than 250 °C. Only annealing at 250 °C can decrease EZD availably and make the PdNi nano-film hydrogen sensor maintain a high Rs and short t rs and t rc. In addition, the sensor annealed at 250 °C is appropriate for detecting hydrogen with low concentration and the detection limit is low to 2 ppm. • Zero drift of PdNi film hydrogen sensor is effective inhibited by vacuum annealing. • Anneal promotes grain growth, lattice constant decrease and defect reduction of PdNi. • The effect of zero drift on hydrogen sensing is quantitative analyzed innovatively. • Annealing at 250 °C restrains zero drift availably and maintains good performances. • The sensor annealed at 250 °C can monitor hydrogen with ppm-level more accurately. [ABSTRACT FROM AUTHOR]

Aim :This study aims to identify suitable candidates for axillary sentinel lymph node biopsy (SLNB) or targeted axillary dissection (TAD) among clinical N2 (cN2) triple-negative (TN) or HER2 positive (HER2+）breast cancer patients following neoadjuvant therapy（NAT）. Background: Despite the substantial axillary burden in cN2 breast cancer patients, high pathological response rates can be achieved with NAT in TN or HER2+ subtypes, thus enabling potential downstaging of axillary surgery. Methods: A retrospective analysis was conducted on data from the CSBrS-012 study, screening 709 patients with initial cN2, either HER2+ or TN subtype, from January 1, 2010 to December 31, 2020. The correlation between axillary pathologic complete response (pCR) (yPN0) and breast pCR was examined. Results: Among the 177 cN2 patients who achieved breast pCR through NAT, 138 (78.0 %) also achieved axillary pCR. However, in the 532 initial clinical N2 patients who did not achieve breast pCR, residual axillary lymph node metastasis persisted in 77.4 % (412/532) of cases. The relative risk of residual axillary lymph node metastasis in patients who did not achieve breast pCR was 12.4 (8.1–19.1), compared to those who did achieve breast pCR, P < 0.001. Conclusion: For cN2 TN or HER2+ breast cancer patients who achieve breast pCR following NAT, consideration could be given to downstaging and performing an axillary SLNB or TAD. [ABSTRACT FROM AUTHOR]

Highlights: [•] Platinum–10% rhodium vs. platinum thin film thermocouples were fabricated on nickel based superalloy substrate. [•] The Seebeck coefficient increases from 7.7μV/°C to 8.28μV/°C by vacuum anneal. [•] The error between thin film thermocouples and standard wire thermocouple is limited to 11°C from 200°C to 1000°C. [ABSTRACT FROM AUTHOR]

In order to measure the surface temperature of aerospace hot-end components accurately, AlN thin film temperature measurement technology was explored. In this research, C-axis preferred orientation AlN thin film was deposited on Ni-based superalloy substrates by medium frequency (MF) reaction magnetron sputtering. Effect of temperature on the lattice structure of AlN thin film was studied. X-ray diffraction results show that the diffraction angles (2 θ) of AlN thin films shift to the left side monotonously with the increase of annealing temperature and annealing time. Based on this phenomenon, the maximum temperature experienced by the film can be deduced according to 2 θ values. A temperature interpretation algorithm equation was established with MATLAB. The algorithm is a binary linear equation, whose dependent variable is 2 θ and the independent variables are annealing temperature and annealing time. Then, temperature interpretation software was developed with Visual Studio 2019. The temperature interpretation range is 700–1200 °C and the relative interpretation error is less than 4.26%. [ABSTRACT FROM AUTHOR]

Abstract The oxidation-resistance of thin film sensors, particularly at high temperatures, is critical for the lifetime and performance of the sensor. The preparation and oxidation-resistance of an Al 2 O 3 /ZrBN-SiCN/Al 2 O 3 composite film with a sandwich-structure was performed using reactive magnetron sputtering. The microstructure evolution of the composite film is examined herein using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analysis. Oxygen diffusion was significantly inhibited by the formation of crystalline Al 2 SiO 5 and Zr-B-C amorphous phase inside the composite film. The Pt-13%Rh/Pt thin film thermocouple (TFTC) with the Al 2 O 3 /ZrBN-SiCN/Al 2 O 3 composite film as a protective layer was fabricated and calibrated. Both the stability and lifetime of the TFTC was significantly enhanced for temperatures up to 1000 ℃. The test error of the TFTC was reduced by half, compared with that of the TFTC with the Al 2 O 3 protective layer, indicating an excellent oxidation-resistant performance of the composite film. [ABSTRACT FROM AUTHOR]

The insulating layer plays a vital role to provide adequate electrical insulation for developing sputtered thin film sensors on Ni-based turbine blades of aircraft engine running at high temperature environment. Here, the multilayered YSZ/Al 2 O 3 thin film as insulating layer was deposited by reactive sputtering. The prepared multilayered film exhibited improved insulation property as compared to the single Al 2 O 3 thin film, the insulation resistance of the four-layered YSZ/Al 2 O 3 /YSZ/Al 2 O 3 film increased roughly two orders of magnitude. During thermal cycle tests, the four-layered film insulating layer showed stable electrical insulation and no shorts to substrate occurred up to 800 ℃. Subsequently, the PdCr thin film strain gauge using the four-layered film as insulating layer was fabricated on Ni-based substrate and performed very well with highly sensitive resistance-strain response, stable apparent strain output and no drift error at elevated temperatures, indicating the feasibility and validity of the four-layered YSZ/Al 2 O 3 /YSZ/Al 2 O 3 film as insulating layer for high temperature thin film sensors. [ABSTRACT FROM AUTHOR]

Increasing evidence showed that microRNAs (miRNAs) were abnormally expressed in cancers and made effects on the tumorigenesis. Aberrant expression of miR-20a-5p has been reported in human breast carcinoma. However, the functional mechanism of miR-20a-5p in human breast carcinoma, particularly in triple-negative breast cancer (TNBC), required further investigations. Here, firstly, we determined that miR-20a-5p was highly expressed in both TNBC tissues and cell lines. Then, we explored that the overexpression of miR-20a-5p promoted the migration and invasion of TNBC cells in vitro. The tendency was significantly reversed after the depletion of miR-20a-5p. Consistent result could be obtained with the in vivo nude mice tumorigenesis. Thirdly, the underlying molecular mechanism was investigated. The Runt-related transcription factor 3 (RUNX3) was identified as a target of miR-20a-5p in TNBC cells. High expression of miR-20a-5p significantly decreased both the mRNA and protein levels of RUNX3, as well as its direct downstream targets Bim and p21. These results verified the significance of miR-20a-5p and explored its functional mechanisms in TNBC, suggesting the potential clinical applications of miR-20a-5p in TNBC. [ABSTRACT FROM AUTHOR]

Electrical insulation of nickel-based superalloy substrate, especially at high temperature range, is one of the major challenges for the reliability and stability of the integrated thin-film sensors. Here, we report a solution-processed approach to fabricating high-temperature, electrically insulating coatings on Ni-based superalloy substrates. NiCrAlY coatings were fabricated by DC magnetron sputtering and heat-treated, and then Al 2 O 3 films were deposited by sol-gel method. X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscopy were used to characterize the composition, phase, microstructure and morphology of these composite coatings. The electrical resistance of the composite coating was measured as a function of temperature up to 800 °C. Electrical resistance greater than 1 MΩ were consistently achieved from 600 °C to 800 °C. Moreover, this insulating coating survived thermal shock and thermal fatigue tests without cracking or delaminating. A type S thin-film thermocouple was prepared on the composite coating to verify its high-temperature electrical insulation performance. [ABSTRACT FROM AUTHOR]

Thin film thermocouples could provide precise temperature measurement of the hot components of gas turbine engines with fast response in harsh environments. ITO thin films were prepared by radio frequency magnetron sputtering in pure argon atmosphere and annealed in air at 1000 °C. The variation of the microstructure and electrical properties of indium tin oxide thin films with annealing was disclosed. ITO/Pt thin film thermocouple was fabricated on Ni-based superalloy substrate by sputtering with stencil mask. And the thermoelectric performance and stability of the thin film thermocouples were characterized with temperature up to 1100 °C. [ABSTRACT FROM AUTHOR]

Platinum (Pt) thin-film resistance temperature detector was fabricated on the flexible Hastelloy tapes using magnetron sputtering and MEMS processes. NiCrAlY buffer layer and AlON/Al 2 O 3 insulating layer were deposited on the tapes for stress release and electrical insulation. Post annealing was applied to improve the stability of the sensors. The performance of the sensor was calibrated with temperature up to 550 °C. Compared with the sensor on the alumina ceramic substrate, the sensor on Hastelloy tapes have much smaller thermal hysteresis, higher linearity and excellent stability. Moreover, this flexible sensor can be easily integrated with the metallic components by the welding and the maximum curvature of the sensor is 2 cm−1. This Pt thin-film temperature sensor has great potential in the surface temperature measurement of hot components in harsh environment. • This Hastelloy tape based RTD has small thermal hysteresis, higher linearity and excellent stability. • AlON/Al 2 O 3 structure ensures the electrical insulation between the Pt film and the metallic substrate. • This flexible sensor can be easily integrated with metallic components for surface temperature measurement. [ABSTRACT FROM AUTHOR]

MgAl hydride films with different hydrogen contents were fabricated in Ar and H 2 mixed atmosphere using magnetron sputtering. Neutron reflectometry was performed to measure hydrogen contents, which indicated that up to 11atom% hydrogen was absorbed into MgAl. The MgAl hydride films were irradiated using pulsed lasers and the electron temperature and density of the generated plasma was measured. Results showed the electron temperature and density at delay time of 1μs were 7330 K, 7.9 × 1015 cm−3 and 8044 K, 9.0 × 1015 cm−3 for MgAl hydride films with 5atom% and 11atom% hydrogen, respectively. For comparison, the electron temperature and density for pure MgAl film were 5634 K and 6.9 × 1015 cm−3. Obviously, the electron temperature and density increases with the hydrogen content. Subsequently, the conversion ratio of the shock wave energy to the incident pulse energy were analyzed by investigating plasma induced shock wave evolution. The conversion ratio for MgAl hydride films with 5atom% and 11atom% hydrogen was 19.2% and 28.6%, which was 1.2 and 1.8 times of that for the MgAl film. Therefore, the MgAl hydride film promised to be a new class of material capable of promoting the plasma generation of the laser-driven flyers. • MgAl hydride films with up to 11atom% hydrogen were successfully prepared. • The increase of the hydrogen content in MgAl hydride films lead to higher electron temperature and density. • The conversion ratio for MgAl hydride films with 11atom% hydrogen is 1.8 times of that for MgAl film. • The promotion in plasma generation can be ascribed to the extra energy released from the laser-induced phase explosion of H 2. • MgAl hydride film promises to be a new class of material capable of promoting the plasma generation of the LDFs. [ABSTRACT FROM AUTHOR]

Nitrogen doped indium tin oxide (ITO) and platinum thin films were fabricated on alumina substrate by magnetron sputtering and formed thin film thermocouples (TFTCs) with stencil mask. After annealing in N 2 or air, the thermoelectric properties of the TFTCs were calibrated for multiple cycles with different calibration atmospheres. The Seebeck coefficient of ITO thin films at high temperature was obtained. The element segregation and oxygen vacancy was stabilized by the formation of oxynitrides in ITO films. And their effects on the Seebeck coefficient of ITO films was discussed. • The Seebeck coefficient of ITO films at high temperature is dictated by the oxygen diffusion. • The formation of oxynitrides could stabilize the oxygen vacancy of ITO films. • The Seebeck coefficient of ITON films demonstrates excellent reproducibility. [ABSTRACT FROM AUTHOR]