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This paper sketched the basic principles of ceramic materials radioactivity measurement and mathematical calculation formula of testing time. When the sample measurement conditions and the way of data analysis are constant, using sodium iodide gamma spectrometer for getting the radioactive spectra data of 5 groups of samples. In condition of the background count time tb or sample measurement time ts increasing gradually, study the radioactivity specific activity measurement error range of all samples. It is derived when the background count rate of nb and sample counting rate ns is constant, the measurement error ν2 and the sum of reciprocal of the background count time tb and reciprocal of the sample measuring time ts for approximately linear positive correlation. The measurement error of 226Ra, 232Th, 40K radioactive specific activity of different ceramic samples presents the corresponding fluctuations as their initial energy spectrum count rate differences. This study for coordination of the contradiction between ceramic materials radioactive measurement time and the uncertainty has certainly theoretical and practical value.

Objective: To explore the pharmacological basis and mechanism of Buxue Yimu pills (BYP) in the treatment of anaemia in women from the perspective of metabolomics and network analysis.Materials and Methods: Forty-six women of reproductive age with haemoglobin 70–110 g/L were recruited. Blood samples were collected before and after 4 weeks of oral BYP treatment to assess the changes in haemoglobin, coagulation function, and iron metabolism indices. An integrated analysis of metabolomics (liquid chromatography mass spectrometry) and network analysis was performed to identify the potential pharmacodynamic mechanisms of BYP.Results: After BYP treatment, the haemoglobin level of patients significantly increased from 93.67 ± 9.77 g/L to 109.28 ± 12.62 g/L (p < 0.01), while no significant changes were found in iron metabolism and coagulation-related indicators. A total of 22 differential metabolites were identified after metabolomics analysis, which were mainly related to the inhibition of inflammation and oxidative stress. Integrating pharmacodynamics and metabolomics, a network of drug-active components-targets-metabolic pathways-metabolomics was established. Acetylcholinesterase, phospholipase A2 group IIA, and phospholipase A2 group IVA may be the most promising therapeutic targets.Conclusion: BYP can inhibit inflammation and oxidative stress as well as promote haematopoiesis, potentially improving anaemia.

The preparation of 7×××series aluminum alloy by selective laser melting technology (SLM) is hindered by hot tearing. Novel ZrH2 modified 7075 composite powders were prepared by the low-energy ball milling technology. Zirconium-containing 7×××series aluminum alloy was then prepared by the SLM process. The microstructure and mechanical properties of the samples with different ZrH2contents (0.5%, 1.0%, 1.5%, mass fraction, the same below) were systematically investigated. The results show that the addition of ZrH2 can significantly reduce hot tearing and change the microstructure. When 1.5% ZrH2 is added, the hot tearing is completely eliminated and the grain microstructure is entirely composed of fine equiaxed grains. The transition of columnar grains to equiaxed grains is attributed to the in-situ formation of L12-Al3Zr which provides numerous nucleation positions for solidification. After T6 heat treatment, the tensile strength, yield strength and elongation of SLMed sample are (550±10), (490±5) MPa and (12±1)%, respectively. Fractography analysis shows a large number of dimples on the fracture surface after tensile testing, indicating ductile fracture mode.

Micro-arc oxidation (MAO) ceramic coatings were prepared on Ti2AlNb alloy in silicate/phosphate electrolytes with different concentrations of Na2WO4. The influence of Na2WO4 on the coating growth process, coating structure and composition was analyzed by SEM, XRD and XPS. The tribological behavior of MAO coatings was evaluated by the ball-disc wear test. The results show that the growth rate of MAO coating in electrolyte without Na2WO4 is only 0.08μm/min, meanwhile, the coating is loose and rough, and "networks" connecting with big pores exist on the coating surface.The main phase compositions of this coating are rutile TiO2, anatase TiO2, Al2O3, and Nb2O5. The addition of Na2WO4 in the electrolyte shortens the time before sparking of Ti2AlNb alloy, increases the growth rate of the coating, improves the uniformity of coating and meanwhile, a small amount of WO3 is introduced in the coating. Besides, MAO coatings formed in the participation of Na2WO4 have better wear resistance. Severe abrasive wear occurs when the test is made on Ti2AlNb alloy with Si3N4, the friction coefficient reaches 0.5-0.7. Both the friction coefficient and wear rate decrease obviously when Ti2AlNb is treated by MAO. The friction coefficient and wear rate of MAO coating prepared in the electrolyte with 4g/L Na2WO4 are 0.24 and 6.2×10-4mm3/(N·m), respectively. Only "fish scales" caused by fatigue wear appears on the coating surface.

First, the quantitative characterization of cement paste backfilling (CPB) material characteristics was studied, and a comprehensive index called solid filling rate was presented to describe the interaction of material characteristics, through analyzing the substance composition of CPB microstructure. Then, rheological experiments were made to get the corresponding rheological curves, which were fitted by the Bingham model to get the yield stress and plastic viscosity of CPB. The influence of material characteristics such as volume fraction, weighted average grain diameter, nonuniform coefficient, the mass fraction of fine particles and cement on CPB rheological parameters was analyzed, and its mechanism was explained from the view of microstructure. At last, a calculation model of rheological parameters including solid filling rate was constructed. The results indicate that under the same conditions, the yield stress and plastic viscosity increase exponentially along with the increase of volume fraction, decrease with the increase of nonuniform coefficient, and decrease first and increase soon with the increase of fine particles.

As a plastic fluid, the morphological features of internal structure in an unclassified tailing paste closely relate to its flow properties. Studies on the evolution characteristics of internal structure during the sheafing flow process have extremely important significance for analyzing flow behavior in pipeline transportation and paste preparation. In this paper, scanning electron microscopy was used to investigate the meso-structure images of the paste at different mixing time. The fractal dimensions of these meso-structure images were estimated by the image processing technology and fractal theory. A structure coefficient A was put forward to explain the morphological features of meso-structure, and a time-evolution mathematical model of meso-structure was built in the mixing process. Some related experiments were done for a lead-zinc tailing paste. It was found that the structure coefficient A flattened out gradually after a steep fall with mixing time, and finally reached an equilibrium state. The failure coefficient and restitution coefficient in the evolution model were obtained to be 0.171 and 0.491 respectively by fitting experimental data.

Aging is an intricate process involving interactions among multiple factors, which is one of the main risks for chronic diseases, including Alzheimer's disease (AD). As a member of cysteine protease, cathepsin S (CTSS) has been implicated in inflammation across various diseases. Here, we investigated the role of neuronal CTSS in aging and AD started by examining CTSS expression in hippocampus neurons of aging mice and identified a significant increase, which was negatively correlated with recognition abilities. Concurrently, we observed an elevation of CTSS concentration in the serum of elderly people. Transcriptome and fluorescence‐activated cell sorting (FACS) results revealed that CTSS overexpression in neurons aggravated brain inflammatory milieu with microglia activation to M1 pro‐inflammatory phenotype, activation of chemokine C‐X3‐C‐motif ligand 1 (CX3CL1)—chemokine C‐X3‐C‐motif receptor 1 (CX3CR1) axis and janus kinase 2 (JAK2)—signal transducer and activator of transcription 3 (STAT3) pathway. As CX3CL1 is secreted by neurons and acts on the CX3CR1 in microglia, our results revealed for the first time the role of neuron CTSS in neuron–microglia “crosstalk.” Besides, we observed elevated CTSS expression in multiple brain regions of AD patients, including the hippocampus. Utilizing CTSS selective inhibitor, LY3000328, rescued AD‐related pathological features in APP/PS1 mice. We further noticed that neuronal CTSS overexpression increased cathepsin B (CTSB) activity, but decreased cathepsin L (CTSL) activity in microglia. Overall, we provide evidence that CTSS can be used as an aging biomarker and plays regulatory roles through modulating neuroinflammation and recognition in aging and AD process. [ABSTRACT FROM AUTHOR]

Porphyrins‐based porous organic polymers (POP) were widely used in photocatalytic oxidation under visible light owing to their superiority in the activation of oxygen. In contrast, the efficiency is usually limited due to the fast recombination and slow electron transfer. Herein, we report the use of a trioporphyrins‐based covalent triazine framework (Por‐CTF) as visible‐light‐active photocatalyst for the coupling oxidative of amines to imines at room temperature. By incorporating the π‐conjugated porphyrin building block led to the enhanced electron transport between molecules, and the extended recombination time of excited electrons. The photocatalytic efficiency of Por‐CTF is superior to that of polymer in absence of triazine framework (POP‐TSP), which was prepared by radical polymerization using tetra‐(4‐vinylphenyl) porphyrin (TSP) as monomer. Por‐CTF catalyst presented excellent efficiency for various primary amines and stability. This work provides a reasonable guidance of catalyst molecular structure design for enhancing efficiency in the photocatalytic oxidation. [ABSTRACT FROM AUTHOR]