This study mainly focused on an orthogonal optimization design of low-density and high-strength ceramic proppants prepared by low-grade bauxite and feldspar that met the standard requirements. The ...orthogonal experimental design of L25 (53) was employed to study the significance sequence of three factors, including milling time of bauxite, milling time of feldspar, and sintering temperature. The results show that the particle size of feldspar is the most important factor for the performance of the proppants. The longer the milling time of feldspar is, the finer the particle size of feldspar is, and the easier it is to form liquid phase at a lower temperature. For the breakage ratio, the optimal experimental combination is bauxite milled for 4 h, feldspar milled for 8 h, and sintering temperature of 1280°C. The proppants prepared by the optimal combination have bulk density of 1.48 g cm−3, apparent density of 2.7 g cm−3, breakage ratio of 4.07% under 52 MPa closed pressure, and acid solubility of 2.15%.
In this study, a novel friction material with biomass-ceramic (SiC) dual matrixes was fabricated using Chinese fir pyrocarbon via the liquid-phase silicon infiltration and in situ growth method. SiC ...can be grown in situ on the surface of a carbonized wood cell wall by mixing and calcination of wood and Si powder. The samples were characterized using XRD, SEM, and SEM-EDS analysis. Meanwhile, their friction coefficients and wear rates were tested to study their frictional properties. To explore the influence of crucial factors on friction performance, response surface analysis was also conducted to optimize the preparation process. The results showed that longitudinally crossed and disordered SiC nanowhiskers were grown on the carbonized wood cell wall, which could enhance the strength of SiC. The designed biomass-ceramic material had satisfying friction coefficients and low wear rates. The response surface analysis results indicate that the optimal process could be determined (carbon to silicon ratio of 3:7, reaction temperature of 1600 °C, and 5% adhesive dosage). Biomass-ceramic materials utilizing Chinese fir pyrocarbon could display great promise to potentially replace the current iron-copper-based alloy materials used in brake systems.
The objective is to evaluate the primary mechanical and physical properties of particleboard made from hammer-milled rice straw particles of six different categories and two types of resins. The ...results show the performance of straw particleboards is highly dependent upon the straw particle size controlled by the opening size of the perforated plate inside the hammer-mill. The static bending and internal bonding strength of polymeric diphenylmethane diisocyanate (pMDI) resin-bonded boards initially increase then decrease with decreased particle size. The thickness swelling, water absorption, and linear expansion of particleboards decrease with increasing particle size. Compared with pMDI resin-bonded panels, the rice straw particleboard bonded using urea-formaldehyde resin exhibits much poorer performance. The optimized panel properties, obtained when using 4% pMDI and straw particles hammer milled with a 3.18mm opening perforated plate, exceeded the M-2 specification of American National Standard for Wood Particleboard.
Bisphenol A (BPA) is a widespread pollutant threatening the ecosystem and human health. An effective BPA degrader YC-JY1 was isolated and identified as
sp. The optimal temperature and pH for the ...degradation of BPA by strain YC-JY1 were 30 °C and 6.5, respectively. The biodegradation pathway was proposed based on the identification of the metabolites. The addition of cytochrome P450 (CYP) inhibitor 1-aminobenzotriazole significantly decreased the degradation of BPA by
sp. YC-JY1.
BL21 (DE3) cells harboring pET28a-
achieved the ability to degrade BPA. The
gene knockout strain YC-JY1Δ
was unable to degrade BPA indicating that P450
was an essential initiator of BPA metabolism in strain YC-JY1. For BPA polluted soil remediation, strain YC-JY1 considerably stimulated biodegradation of BPA associated with the soil microbial community. These results point out that strain YC-JY1 is a promising microbe for BPA removal and possesses great application potential.
Background/Aims: Osteoarthritis (OA) as a degenerative disease is a major problem in ageing populations. To better understand the molecular mechanisms in the pathogenesis of OA, this study explored ...the role of microRNA (miR)-146a in the articular chondrocytes. Methods: The articular chondrocyte line ATDC5 was used to simulate inflammatory injury by LPS administration in vitro. Cell viability, apoptosis, mRNA expressions and productions of inflammatory factors were assessed, respectively. Mir-146a and Cxcr4 mRNA expressions were measured by qRT-PCR. Targeting effect of miR-146a on Cxcr4 3’UTR was assessed by luciferase activity analysis. Protein expression levels of CXCR4 and main factors in PI3K/AKT, Wnt/β-catenin signal pathways were measured by western blotting. Results: LPS exposure suppressed cell viability, prompted apoptosis of ATDC5 cells, and stimulated expression and release of inflammatory factors. MiR-146a was upregulated in LPS-induced cells. Overexpression of miR-146a further aggravated LPS-induced inflammatory injury, while it was reduced after miR-146a was knocked down. CXCR4 expression was negatively regulated by miR-146a. CXCR4 was a direct target of miR-146a and thus involved in regulatory effect of miR-146a on the injured chondrocytes, which was also related with phosphorylation levels of PI3K/AKT and expressions of Wnt/β-catenin signal factors. Conclusion: miR-146a promoted inflammatory response of articular chondrocytes via targeting CXCR4 and suppressing CXCR4 expression. Overexpression of CXCR4 could attenuate the inflammatory injury. Our findings provided novel evidence which might be useful for further studies exploring therapeutic approaches for OA via targeting miR-146a.
Site-specific variations are challenges for pooling analyses in multi-center studies. This work aims to propose an inter-site harmonization method based on dual generative adversarial networks (GANs) ...for diffusion tensor imaging (DTI) derived metrics on neonatal brains.
DTI-derived metrics (fractional anisotropy, FA; mean diffusivity, MD) are obtained on age-matched neonates without magnetic resonance imaging (MRI) abnormalities: 42 neonates from site 1 and 42 neonates from site 2. Significant inter-site differences of FA can be observed. The proposed harmonization approach and three conventional methods (the global-wise scaling, the voxel-wise scaling, and the ComBat) are performed on DTI-derived metrics from two sites. During the tract-based spatial statistics, inter-site differences can be removed by the proposed dual GANs method, the voxel-wise scaling, and the ComBat. Among these methods, the proposed method holds the lowest median values in absolute errors and root mean square errors. During the pooling analysis of two sites, Pearson correlation coefficients between FA and the postmenstrual age after harmonization are larger than those before harmonization. The effect sizes (Cohen's d between males and females) are also maintained by the harmonization procedure.
The proposed dual GANs-based harmonization method is effective to harmonize neonatal DTI-derived metrics from different sites. Results in this study further suggest that the GANs-based harmonization is a feasible pre-processing method for pooling analyses in multi-center studies.
•The new anchoring capsule is prepared by a ternary complex system.•Orthogonal experiment is designed to optimize the synthesis of anchoring capsule.•The optimal combination of the anchoring capsule ...is A2B3C1D2.•The strengthening mechanism of cement based anchoring capsule is discussed.
Based on orthogonal test design, the mix design of cement based anchoring capsule was optimized. Through the direct analysis and range analysis of the orthogonal test results, of the four factors, lithium carbonate has the strongest effect on the performance of anchoring capsule, while the effect of gypsum is the least. The optimal combination is 710 kg/t of sulphoaluminate cement, 190 kg/t aluminate cement, 0.92 kg/t of lithium carbonate, 16.2 kg/t of sodium carbonate and 96 kg/t of gypsum. The prepared anchoring material has superior performance. Furthermore, the strengthening mechanism of cement based anchoring capsule is discussed.
YC-XJ1 isolated from desert soil exhibited a diverse degrading ability towards aromatic oxyphenoxypropionic acid esters (AOPPs) herbicide, phthalate esters (PAEs), organophosphorus flame retardants ...(OPFRs), chlorpyrifos and phoxim. The genome of YC-XJ1 was sequenced and analyzed systematically. YC-XJ1 contained a large number of exogenous compounds degradation pathways and hydrolase resources. The quizalofop-p-ethyl (QPE) degrading gene
and diethyl phthalate (DEP) degrading gene
were cloned and expressed. The characteristics of corresponding hydrolases were investigated. The specific activity of recombinant QPEH2 was 0.1 ± 0.02 U mg
for QPE with
/
values of 1.8 ± 0.016 (mM
·s
). The specific activity of recombinant DEPH1 was 0.1 ± 0.02 U mg
for DEP with
/
values of 0.8 ± 0.02 (mM
·s
). This work systematically illuminated the metabolic versatility of strain YC-XJ1 via the combination of genomics analysis and laboratory experiments. These results suggested that strain YC-XJ1 with diverse xenobiotics biodegrading capacity was a promising candidate for the bioremediation of polluted sites.
Herein, the coupling interactions between moisture and temperature on the microwave absorption of poplar were investigated quantitatively under microwave heating at 2450 MHz. The inverse physics ...problems have been solved based on the microwave heating curve of poplar wood by a genetic algorithm approach. Meanwhile, the quantitative characterization equation of the microwave absorption power of poplar was obtained. The accuracy of the microwave absorption power equation was verified experimentally, and the interaction mechanism was explained. The results indicated that the microwave absorption power increased with temperature and decreased with a higher original moisture content. Compared with that, the temperature influenced the microwave absorption of poplar wood slightly more than the initial moisture content.
The effect of support and catalyst reduction temperature on the catalytic performance of ruthenium catalysts in the hydrogenolysis of glycerol was studied. The support material can influence the ...metal particle size and the reaction routes. The reaction activity decreases with increasing catalyst reduction temperature, which is attributed to two reasons: (1) the growth in Ru particle size caused by heating treatment; (2) the strong metal-support interaction (SMSI), which results in partially covering of Ru metal particles by Ti
2O
3 species. The covering phenomenon can influence the reaction routes of the hydrogenolysis reaction, and consequently influence the product selectivity.
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