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The circulation pump in a distillation column is a core device in a material circulation system, and its stable operation is crucial for the production process. The impeller of the circulation pump is prone to failure due to long-term contact with corrosive media, and subjected to a large amount of material erosion, which severely challenges the safety control of the distillation reaction system. Focusing on the corrosion failure phenomenon of circulation pump impellers, the failure mechanism was studied by means of macroscopic inspection, chemical composition analysis, metallographic examination, scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). Results indicated that the corrosion of circulation pump impellers was the result of the combined effects of surface wear, cavitation, and halogen element corrosion. The medium in contact with the impeller contained chloride ions, fluoride ions, and solid particles. During circulation pump operation, a low-pressure zone formed at the inlet, generating numerous water vapor bubbles. These bubbles burst in the high-pressure zone, creating highly localized impact forces. Combined with the abrasive action of solid particles on the impeller surface, this led to the destruction of the passivation film and the formation of numerous small pits. These corrosion pits and the surrounding environment formed micro-galvanic corrosion cells with small anodes and large cathodes. Under the accelerated corrosion caused by fluoride and chloride ions, the corrosion process towards the inner wall of the impeller intensified, ultimately leading to impeller failure. This study clarified the corrosion failure mechanism and its root causes in the 2507 duplex stainless steel circulation pump impeller and proposes corresponding improvement recommendations, providing a scientific basis for preventing similar issues from occurring in the future. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Resources & Environment / Nongye Ziyuan yu Huanjing Xuebao is the property of Journal of Agricultural Resources & Environment Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mountain Research (10082786) is the property of Mountain Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Esophageal variceal bleeding (EVB) is a potentially fatal complication of cirrhosis. The purpose of the present study was to evaluate the safety and efficacy of a novel technique of balloon-occluded esophageal varices (EVs) obliteration (BEVO) for EVs classified as F2 (medium size, F2-EVs) and F3 (large size, F3-EVs). Materials and Methods: Between December 2020 and December 2021, a total of 73 consecutive patients with EVs were treated using BEVO. An injection of sclerosant was administered via direct puncture of the varices during balloon occlusion. Immediate postprocedural Doppler endoscopic ultrasonography (EUS) was conducted to evaluate the blood flow in the EVs. Several factors, including the technical success, controlling of acute bleeding, intraoperative bleeding at the injection site, variceal eradication, variceal recurrence, and BEVO-related complications, were assessed. Results: BEVO was successfully performed in all patients. Immediate hemostasis was achieved in 100% (25/25) of patients with active EVB. The incidence of injection site intraoperative bleeding presenting as oozing and spurting bleeding was 76.71% (56/73) and 8.22% (6/73), respectively. Based on Doppler EUS and endoscopic examination, EVs were completely eradicated in 71 out of 73 patients (97.26%) after three sessions. A total of 3 (4.11%) patients were diagnosed with EV recurrence during follow-up after complete EV eradication. Retrosternal chest discomfort (13.70%; 10/73) and abdominal bloating (2.74%; 2/73) were spontaneously relieved after a few days. No serious BEVO-related complications were observed. Discussion: BEVO is a convenient and effective treatment for obliterating F2 and F3 EVs. Clinical Trial Registration No. ChiCTR2000039974. [ABSTRACT FROM AUTHOR]

The visible infrared radiometer (VIRR) is the first instrument with longest measurements equipped on the Fengyun (FY) polar-orbiting satellites. Through re-processing of the historic VIRR measurements, long-term (over 20 yr) global data can be integrated from multiple participating VIRRs on a consistent radiometric scale, which are valuable to climate and climate change studies. Due to lack of an onboard calibration system for VIRR, the reflective solar bands must be vicariously calibrated. This study applied the multi-site vicarious approach for consistent calibration of the VIRR visible (VIS) and near-infrared (NIR) data, and produced calibration coefficients for five VIRRs on FY-1C/D and FY-3A/B/C. The data quality was then evaluated with observations. The reflectance predicted by using the radiative transfer model over multiple invariant desert and ocean targets was used to derive the calibration slope via a weighted fitting scheme, in which the weights are the inverse of the variance from a radiative transfer simulation evaluated with reference to Aqua moderate resolution imaging spectroradiometer (MODIS). The sensor-specific calibration coefficients were derived on a daily basis by using piecewise polynomials. The calibration reference of the VIRR solar band record was further traced to the Aqua MODIS Collection 6.1 reference calibration with a systematic correction derived from the Libya4 desert. The VIRR record was compared with the Aqua MODIS C6.1 calibration over the polar region based on simultaneous nadir overpass observations. The lifetime relative difference for each sensor are within 3.3% and 4.5% for channels 1 and 2. Invariant deserts were also employed to evaluate the stability and consistency of the VIRR record. In general, the means of the directional and spectral corrected reflectance for each sensor are within 1% of the 20-yr average, implying that the VIRR reflectance of the invariant targets is consistent to within 1% among the sensors for channels 1 and 2. The VIRR data thus derived are reliable. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Seeking high precision actuator and transducer materials potentially applied under high load remains active in recent years. Magnetostrictive property, magnetostriction saturation field HS, and pizeomagnetic coefficient d33 are investigated in Fe81Ga19 alloy under high compressive prestress. The measured saturation magnetostriction remains above 300 ppm in the <001> oriented Fe81Ga19 polycrystalline rod under high compressive prestress up to 431 MPa. Two-stage phenomenon was observed in curves plotted for HS and d33 against compressive prestress σ. The domain rotation path and magnetostriction under different compressive prestress are simulated, and this helps to deeply understand the tested magnetostriction. Based on the simulation, the mathematical equations of HS-σ and d33-σ were established for Fe–Ga <001> oriented crystal revealed two mechanisms, which satisfy proposed functions of experimental data. The high magnetostriction and low saturation field under high prestress indicate that Fe–Ga alloy is possible to be a sound candidate for high load application. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents the table of contents and information regarding the issue's editors, the advisory board, and publication information.

The influence of solidification morphologies, planar and cellular, on the solid-state transformations, martensitic and premartensitic transformations, was studied, respectively, for Ni-Mn-Ga martensitic materials. The martensitic transformation was observed in both planar and cellular morphologies, but the premartensitic transformation was suppressed in the cellular morphology. Moreover, after homogenization, the premartensitic transformation was monitored again. The correlation between the solidification and the solid-state transformation is revealed. The chemical disorder during solidification is considered to understand this correlation. [ABSTRACT FROM AUTHOR]

The visible-IR scanning radiometer (VIRR) of FY1-C/D meteorological satellites consists of 10 bands with 4 different focal plane assemblies (FPAs). However, there are significant band-to-band registration (BBR) errors between different bands, which cannot be compensated for by a simple shift in the along-scan direction. A rigorous BBR frame was proposed to analyze the sources of misregistration in the whisk-broom camera. According to theory, the 45° scanning mirror introduces tangent function style misregistration in the along-track direction and secant function style misregistration in the across-track direction between different bands if the bands are not in the same optical axis. As proven by the experiments of both FY-1C and FY-1D, the image rotation caused by the 45° scanning mirrors plays a major role in the misregistration. However, misregistration between different FPAs does not strictly adhere to this theory. Therefore, a polynomial-based co-registration method was proposed to model the BBR errors for the VIRR. To achieve 0.1 pixel accuracy, a fourth-degree polynomial was used for BBR in the along-scan direction, and a fifth-degree polynomial was used for the along-track direction. For the reflective bands, the root-mean-square errors (RMSEs) of misregistration could be improved from 3 pixels to 0.11 pixels. Limited by matching accuracy, the RMSEs of misregistration between thermal bands and reflective bands were approximately 0.2 to 0.4 pixels, depending on the signal-to-noise ratio. [ABSTRACT FROM AUTHOR]