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• Tricolor phosphors in waste phosphors are enriched by liquid–liquid–powder extraction method. • Kerosene is used as the nonpolar liquid and water is used as the polar liquid. • Dodecylamine acetate is used as the surfactant collector. • Tricolor phosphors recovered from water phase are enriched to 72.5 % with a recovery of 67.4 %. • Reagent cost and wastewater generation are greatly reduced when applying this method for recovery. This study aimed to separate and enrich tricolor phosphors powder including red, blue, and green phosphors in waste phosphors which also contained white phosphors through liquid–liquid–powder extraction method. Kerosene and water were used as the two liquids. Dodecylamine acetate (DAA) was used as the surfactant collector. The operating factors including pH, DAA dosage, kerosene–water volume ratio, solid concentration, extraction temperature, and extraction time, on the enrichment of tricolor phosphors powder were investigated. In addition, the benefit of introducing liquid–liquid–powder extraction method in the recovery procedure of tricolor phosphors from waste phosphors was also evaluated through the comparison of applying hydrochloric acid (HCl) leaching for the separated tricolor phosphors and the waste phosphors. The results indicated that the optimal conditions of liquid–liquid–powder extraction method were that the dosage of DAA was 1.5 kg/ton at pH 3 with a kerosene–water volume ratio of 20/80 (v/v), a solid concentration of 1.25 w/v%, an extraction temperature of 25 °C, and an extraction time of 15 mins. Under these conditions, the grade of tricolor phosphors recovered from the water phase was enriched from its initial grade of 15.0 % in the waste phosphors to 72.5 % with a recovery of 67.4 %. The benefit of introducing liquid–liquid–powder extraction method was that more than 50 % of the reagent cost and nearly 90 % of the wastewater generation were reduced compared to those without liquid–liquid–powder extraction treatment. In addition, white phosphors with a grade of 92.3 % and a recovery of 96.7 % could be recovered from the kerosene phase simultaneously. This study also demonstrates the merit of introducing a physical separation treatment in a resources recovery procedure before chemical treatment. [ABSTRACT FROM AUTHOR]

Abstract Orthogonal turn-milling is a primary method of turn-milling, which is used for cutting. It is widely used for machining difficult-to-cut materials, slender rods, thin-wall rotary parts, and large rotary parts. As with turning and milling, chatter is generated by orthogonal turn-milling and affects machining productivity, machining accuracy, and tool life. Various methods are available to predict the chatter-stability lobes of orthogonal turn-milling, such as the zero-order analytical, multi-frequency solution, temporal finite-element-analysis, semi-discretization, and full-discretization methods. However, the zero-order analytical method may not be suitable for the actual conditions of orthogonal turn-milling. The multi-frequency solution, temporal finite-element analysis, and semi-discretization methods suffer from poor efficiency, and the full-discretization method involves complex iterative equations and halfway discretization. To overcome these obstacles, we propose herein a different stability model for orthogonal turn-milling. We use this model to investigate a cutting process for orthogonal turn-milling and obtain stability-lobe diagrams using the complete discretization method based on the Eulerian method. The diagrams are verified by comparing them against the experimental results for chatter. Furthermore, we simulate and analyze how feed per revolution of tools affects the cutting stability for orthogonal turn-milling. These models and results can provide theoretical guidance for maximizing the processing efficiency and surface quality of workpiece manufactured by orthogonal turn-milling. Highlights • The dynamical models of cutting process are a foundation for stability modeling of orthogonal turn-milling. • The complete discretization method can be applied to orthogonal turn-milling and correctly forecasted the stability. • f a is a principal cutting parameter of orthogonal turn-milling and strongly influences the chatter stability. • The chatter is less likely to happen during finishing machining for orthogonal turn-milling of TC21. [ABSTRACT FROM AUTHOR]

Objective: This study aims to investigate the effect of long non-coding RNA (lncRNA) Gas5 on proliferation, migration, invasion and apoptosis of colorectal cancer (CRC) HT-29 cell line. Methods: CRC and normal tissues were collected and prepared from a total of 126 CRC patients, and normal intestinal epithelial cell line FHC and CRC cell lines (HCT-8, HT-29, HCT-116 and SW-480) were prepared. Gas5 expression was detected by quantitative reverse transcriptase-polymerase chain reaction. HT-29 cell line exhibiting the lowest Gas5 expression was selected for further experimentation and divided into blank, negative control and pcNDA-Gas5 groups. The cell counting kit-8 assay was used to test cell proliferation. Flow cytometry was applied to examine cell apoptosis. Transwell assay was performed to detect the migration and invasion of HT-29 cells. The mRNA and protein expression of factors in the classical proliferation (Akt/Erk) and apoptosis (caspase-9/caspase-3) pathways were detected. Results: Gas5 expression was lower in CRC tissues compared to the adjacent normal tissues, and is also lower in CRC cell lines than FHC cell line. Gas5 expression was associated with tumor size and TNM staging. Gas5 expression, distant metastasis, tumor differentiation and TNM staging were independent CRC prognostic factors. The results showed that elevated Gas5 expression inhibited proliferation, migration and invasion, but promoted apoptosis of CRC cells. Meanwhile, elevated Gas5 expression inhibited mRNA expression of Akt and Erk and protein expression of p-Akt and p-Erk, which promoted Casp9 mRNA and pho-Casp9 protein expression but inhibited Casp3 mRNA and pho-Casp3 protein expression. Conclusion: The findings indicated that overexpression of lncRNA Gas5 can inhibit the proliferation, migration and invasion but promote apoptosis of CRC cells. [ABSTRACT FROM AUTHOR]

The effects of the size of micron SiC particle (SiCp) on the grain refinement, distribution of particle and tensile properties of as-cast AZ31B (Mg-3Al-1Zn-0.3Mn) magnesium matrix composites have been investigated. As the volume fraction of micron SiCp increases to 15 vol%, excellent grain refinement is achieved. Meanwhile, volume fraction of particle is set as same content, grain size of matrix decreases as the size of micron SiCp decreases. This is due to both the uniform distribution and refining effect of the fine particles. The micron SiCp distributes along the grain boundaries. Because of grain refinement strengthening and ceramic phase strengthening effects, the room temperature tensile property of M5-15 has the optimal value of YS 171MPa-UTS 216MPa-EL 0.87 %. [ABSTRACT FROM AUTHOR]