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This article undertakes both theoretical and experimental investigation on the heat and mass transfer properties of wet air and solution (configured sodium hydroxide solution with the concentration of 2%) on the surface of corrugated packings under reduced ambient pressure conditions. Theoretical analysis reveals that a decreased atmospheric pressure environment is conducive to amplifying mass transfer potential difference. However, it concurrently mitigates the maximum possible mass of water vapor per unit volume of air. Subsequently, experiments were carried out under the following conditions: vacuum degree-0 ~ 40 kPa, inlet air velocity-0.8 ~ 1.6 m/s, inlet air temperature-12.0 ~ 22.0 °C, and inlet air relative humidity-50.0 ~ 95.0%. The experimental outcomes indicate that heat transfer coefficient is predominantly influenced by inlet air velocity and vacuum degree. An enhancement of inlet air velocity or a reduction of vacuum degree leads to a corresponding increase of heat transfer coefficient. Under consistent conditions for other parameters, as vacuum degree ascends, moisture absorption rate and efficiency exhibit a steady growth, albeit with a diminishing rate of increment. Under constant inlet air velocity and relative humidity conditions, mass transfer coefficient initially experiences an upsurge as vacuum degree rises, but eventually undergoes a decline. At a fixed inlet air temperature, mass transfer coefficient behaves differently depending on air temperature. It demonstrates a gradual decrease under cooler air temperatures as vacuum degree rises, whereas under warmer air temperatures, it initially increases and then decreases. The analysis reveals that elevating vacuum degree indeed augments mass transfer capability between wet air and solution. However, there exists an upper limit to this enhancement, dictated by the maximum amount of water vapor that wet air can bear upon reaching saturation. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a progressive neurodegenerative disorder. Long non-coding RNA (lncRNA) XIST has been implicated in the development of PD. Herein, we sought to investigate the diagnostic value of serum XIST expression in PD. We recorded clinical baseline data, including age, sex, body mass index (BMI), years of education, and PD family history, for PD patients and healthy controls, in addition to the disease course in PD patients. The disease severity of PD patients was assessed using the Hoehn-Yahr grading scale. We evaluated serum XIST expression levels in PD patients and healthy controls using RT-qPCR and assessed the correlation between serum XIST expression and the Unified Parkinson's Disease Rating Scale (UPDRS) score. Additionally, we used receiver operating characteristic (ROC) curve to determine the diagnostic value of XIST expression for PD. Our results showed no significant differences in age, sex, BMI, and years of education between PD patients and healthy controls. However, more PD patients had a family history of PD. We found that serum XIST expression was significantly up-regulated in PD patients, and its levels were positively correlated with the UPDRS score. Higher PD stage was also associated with increased serum XIST expression. ROC analysis revealed that XIST expression had a diagnostic value for PD. In conclusion, our findings suggest that serum lncRNA XIST expression may serve as a potential diagnostic biomarker for PD. [ABSTRACT FROM AUTHOR]

For the first time, the fault tree mapping dynamic Bayesian network (DBN) method is applied to the reliability research study of centrifugal compressor units, and its usability and reliability are evaluated dynamically. First, the fault data using the K-means method eliminates abnormal data and builds a fault tree model. The structure is mapped to the DBN structure to complete the structure learning, and the logic gate is mapped to the conditional probability to achieve the parameter learning. Then the model is solved bidirectionally. The change rule of system node reliability with time is solved forward, and the posterior probability of the system node is solved reversely to complete fault diagnosis. Finally, Monte Carlo simulation analysis and the Markov process verify the dynamic reliability and steady-state availability. The results show that the Monte Carlo simulation method is almost consistent with the reliability prediction curve of the DBN model. Indicating that the accuracy of the DBN model is reliable and the computational efficiency is improved by about 81434 times. The steady-state availability calculated using the DBN model is approximately 0.99963, which is close to reality compared to the Markov process. This method can better describe centrifugal compressor units' dynamic reliability and maintainability and provide decision support for regular maintenance of essential parts and enterprise procurement. [ABSTRACT FROM AUTHOR]

Ti is regarded as one of the promising grain refiners in cast Al-Li-Cu alloys, but few research works have been done on its independent role. In this study, the effect of Ti on the microstructure evolution and mechanical properties of cast Al-2Li-2Cu-0.5Mg base alloy was investigated. The results revealed that the grains can be prominently refined with the increase of Ti addition. After adding Ti, high density TiB2-Al3Ti composite particles with a low lattice misfit form as heterogeneous nucleation sites for the α-Al matrix. δ'(Al3Li) and T1(Al2CuLi) precipitates that provide enhanced strength are dominated in the alloys after T6 aging treatment. The average size of both δ' and half-width of δ'-precipitation free zone (PFZ) decreases gradually with the increase of Ti content. This is because the higher binding energy between Ti atoms and vacancies limits the diffusion efficiency of Li atoms, and thus results in a higher ductility. Additionally, no nano-sized Al3Ti or core-shell structure of Al3(Li, Ti) particles are found. The tensile property test results indicate that the Al-2Li-2Cu-0.5Mg alloy achieves optimal properties after aging at 175 °C for 32 h when 0.15wt.% Ti is added. It exhibits a yield strength of 352±5 MPa, an ultimate tensile strength of 423±6 MPa, and an elongation of (3±0.4)%. These findings are expected to offer a reliable theoretical guidance for the industrial composition design of the Al-Li-Cu series cast alloys. [ABSTRACT FROM AUTHOR]

Two sections of the Xintiangou Formation were examined in the Yunyang area, Northeastern Sichuan Basin, China. One of them was systematically sampled from bottom to top. Palynology and geochemistry analyses were performed on 20 samples, and Paleoclimatic indicators were extracted. The sporopollen assemblage indicates arid and hot paleoclimate as a whole, and the geochemical index shows hot and humid paleoclimate. Combined with the analysis of sedimentary characteristics, it shows that the sedimentary period of the Xintiangou Formation in the study area is characterized by arid and hot paleoclimate as a whole, and there were fluctuations of relative moist and arid. The humid climate recorded by geochemical indicators may be the illusion that the unconsolidated sediments transported to the shore shallow lake zone experienced strong weathering. When studying the palaeoclimate characteristics of continental basins, it is necessary to analyze all kinds of palaeoclimate proxy indexes in combination with sedimentary facies, and there may be a deviation in using a single palaeoclimate proxy index to invert the palaeoclimate of continental basins. [ABSTRACT FROM AUTHOR]

Additive manufacturing is expected to transform and upgrade the traditional foundry industry to realize the integrated manufacturing and rapid and low-cost development of high-performance components with complex shapes. The additive manufacturing technology commonly applied in casting mold preparation (fusible molds, sand molds/cores and ceramic cores) mainly includes selective laser sintering (SLS) and binder injection threedimensional printing (3DP). In this work, the research status of SLS/3DPcasting processes on material preparation, equipment development, process optimization, simulation and application cases in aerospace, automotive and other fields were elaborated. Finally, the developing trends of the additive manufacturing technology in the future of foundry field are introduced, including multi-material sand molds (metal core included), ceramic core-shell integration and die-casting dies with conformal cooling runners. [ABSTRACT FROM AUTHOR]