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In this study, resveratrol was substituted for phenol in different molar ratios (4%, 8%, 12%, 16% and 20%) with lignin, phenol and formaldehyde as raw materials, and a new resveratrol modified lignin-based phenolic resin (R-LPF) with high glass transition temperature (Tg) and improved mechanical properties was synthesized. The curing behaviors of phenolic resin (PF), lignin phenolic resin (LPF) and R-LPF were investigated. The thermal mechanical properties, thermal stability, comprehensive mechanical properties, frictional properties and morphology were systematically tested and analyzed. The results show that the highest Tg of the modified R-LPF reaches 346.2 °C. The Ts reaches 231.5 °C, and the residual carbon rate reaches 66.2% at 800 °C. For 12% substitution ratio, the maximum tensile strength, bending strength and impact strength are respective 28.72 ± 1.10 MPa, 57.58 ± 1.95 MPa and 3.14 ± 0.19 KJ/m2. Compared with PF and LPF, the tensile strength of R-LPF is increased by 21.5% and 40.4%, and the bending strength is increased by 6.5% and 30.4%, while the impact strength is increased by 38.9% and 58.6%, respectively. The wear resistance is also significantly improved. The modified R-LPF structure has good rigidity, high crosslinking density, excellent mechanical and thermal properties, and it makes up for the defects of system performance decline caused by the introduction of lignin and provides a direction for the development of green high-performance phenolic resin. [ABSTRACT FROM AUTHOR]

Decidualization plays an important role in the implantation of the embryo, but the molecular action implicated in this process is not completely known. Herein, we found that, compared with the proliferative endometrial tissues, the expression of minichromosome maintenance complex component 6 (MCM6) was markedly decreased in the secretory endometrial tissues. To verify the function of MCM6 in decidualization, in vitro decidualization model was constructed by treating human endometrial stromal cells (HESCs) with estrogen (E2) and progesterone (P4). Consistently, MCM6 level was downregulated in E2P4-treated HESCs. Administration of E2P4 accumulated HESCs in G1 cell cycle phase, leading to cell growth suppression. Ectopic expression of MCM6 promoted the transition of G1/S and restored the proliferation of HESCs that were inhibited by E2P4. MCM6 overexpression led to aberrant activation of extracellular signal-regulated kinase (ERK) and treatment with ERK agonist Ro 67–7476 restored MCM6 expression and cell proliferation inhibited by E2P4. Our data suggested that MCM6/ERK feedback loop plays a negative role in E2P4-induced decidualization and implies that MCM6 may be a promising target for meliorating uterine receptivity. [ABSTRACT FROM AUTHOR]

In the backdrop of an ever-expanding urban transportation road network, the dramatic changes in traffic flow make traffic flow forecasting become a challenge. Which encompass intricate spatial correlations and intricate non-linear temporal relationships. Given a complex time series of traffic flow, accurately predicting traffic flow under such circumstances becomes an arduous task, particularly for long-term sequences. To tackle this conundrum, we put together a traffic prediction framework called the multi-scale attention-based graph convolutional recurrent network (MAGRN). Based on GCN and RNN, this framework skilfully extracts dynamic spatial and temporal features from node attributes. By incorporating multi-scale feature extraction and two attention mechanisms within the attention structure, MAGRN adeptly captures features at varying granularities. This enables MAGRN to diligently capture both the temporal interdependencies and spatial correlations inherent in traffic sequences, thereby minimizing errors. Experimental validation on three real-world traffic datasets unequivocally attests to the superior performance of the MAGRN model. [ABSTRACT FROM AUTHOR]

It is of interest to develop wide-temperature domain damped hydrophobic materials. In this paper, we designed incorporating bio-based phenolic resin into the IIR matrix and introducing dibenzyl fork acetone (DBA) into the main chain structure with sodium hydroxide activation to construct three-dimensional network. In this paper, we designed incorporating bio-based phenolic resin into the IIR matrix and introducing dibenzyl fork acetone (DBA) into the main chain structure with sodium hydroxide activation to construct three-dimensional network. The added bio-based phenolic resin has reticulated structure blended with butyl rubber, combined with sodium hydride activation-modified IIR. The results show that sodium hydride activated modification of DBA is introduced into the main chain structure of IIR by infrared and 1H NMR analysis. The material hydrophobic is realized by the introduction of DBA with static water contact angle of 103.5°. The addition of 10phr lignin-based phenolic resin (LPF) is compatible with IIR, and the torque can reach 7.0 N-m. The tensile elongation of the modified butyl rubber composite can reach 2400% with tensile strength up to 11.43 MPa, while the damping factor can reach 0.37 even at 70 °C. The thermal stability of the composites is enhanced with mass retention rate of 28%. The bio-based PF/NaH activation-modified butyl rubber damping material has potential applications in damping hydrophobicity with wide temperature range. [ABSTRACT FROM AUTHOR]

Low toxicity, environmentally friendly and sustainable bio-based phenol–formaldehyde (PF) resins are the primary factors and health goals that researchers need to consider when modifying PF resins. Two novel biomass-modified PF resins were synthesized using two flavonoid phenols of daidzein and naringenin with rigid backbone structures. The results show that compared with ordinary PF, the introduction of daidzein and naringenin during the synthesis of N-PF and D-PF can delay the curing reaction and results in higher curing peak temperatures. The appropriate substitution rate of daidzein and naringenin can improve the crosslinking degree, resulting in N-PF and D-PF with higher thermal stability, ablation resistance and mechanical properties. The highest carbon yield YC800 for N-PF is 59.81% (56.85%for PF-1), and the highest YC800 for D-PF is 64.39% (PF-2 with 58.15%). The maximum tensile strength and flexural strengths of N-PF are respective 33.86 MPa and 110.42 MPa (28.77 and 79.89 MPa for PF-1), and the maximum tensile strength and flexural strengths of D-PF are respective 35.61 MPa and 103.17 MPa (24.48 and 55.79 MPa for PF-2). The D-PF and N-PF resins modified and enhanced by daidzein and naringenin have lower friction coefficient and more excellent wear resistance than pure PF. [ABSTRACT FROM AUTHOR]

18Ni 300 maraging steel parts were prepared by laser cladding deposition (LCD) and powder bed selective laser melting (SLM) processes. Electrochemical corrosion behaviors of as-printed steel parts were evaluated in acidic, basic, and neutral aqueous solutions, including 10% H2SO4, 3.5% NaCl, 10% NaOH and 10% Na2S. The crystallographic phases and microstructure of as-fabricated steel parts were determined by x-ray diffraction and scanning electron microscopy, respectively. Meanwhile, electrochemical corrosion behaviors of as-built steel parts by LCD and SLM processes in the corroding solution were evaluated by immersion test, potentiodynamic polarization and electrochemical impedance spectroscopy techniques. The results show that as-printed steel parts mainly contained martensite phase and a small quantity of retained austenite. The density of LCD steel part was much more than that of SLM steel part. LCD steel part comprised high martensite content due to high power for Nd:YAG solid pulse laser. Electrochemical corrosion resistance of SLM steel part was better than that of LCD steel part in 10% H2SO4 solution due to high volume fraction of retained austenite unevenly distributed in SLM steel part. However, the corrosion resistance of as-melted steel part by LCD process has an opposite effect in other corrosive solutions due to high density and better chemical homogeneity, compared with as-built steel part by SLM process. The corrosion rates of 18Ni 300 maraging steel parts printed by LCD and SLM processes in the corroding solution ascended in the order of NaOH < NaCl < Na2S < H2SO4. [ABSTRACT FROM AUTHOR]

The hydrothermal method was used to synthesize carbon sphere, and the hard template synthesis method was used to prepared C-doped hollow TiO2 sphere (CHTS). Bismuth nitrate was used as bismuth source to modify CHTS. The composite material was oxidized in air atmosphere at 450℃ to obtain Bi2O3 modified C-doped TiO2 hollow spheres(BCHTS). The morphology, elemental composition and photocatalytic degradation efficiency of tetracyclines (TC) by BCHTS hollow spheres were characterized by various measurements. Additionally, the possible transformation pathways and degradation mechanism of tetracycline were revealed via LC–MS and trapping experiments. The experimental results show that the Bi nanoparticles are uniformly dispersed in the CHTS. The photocatalyst exhibits enhanced degradation rate of TC (98.4% under visible-light within 180 min and 99.4% under natural light within 50 min) for its structure and narrow bandgap (2.87 eV). After five degradation cycles, the photocatalyst still remains high removal rate of 96.4% for TC. The results indicate that the photocatalyst may be promising for degrading antibiotic residuals remains. According to the trapping experiment, OH and h+ have a certain role on the photodegradation process, while·O2− is the main active species for degrading TC. [ABSTRACT FROM AUTHOR]

Background: Decidualization is critical for embryo implantation and the success of pregnancy; however, the mechanisms underlying this process remain largely unknown. Materials and methods: In the present study, RNA sequencing was used to detect the expression levels of transducer of ERBB2/1(TOB1) in endometrial samples derived from proliferative and secretory phases. A decidualization model was induced using the combination of estrogen (E2) and progestin (P4) in human endometrial stromal cells (HESCs). The cell counting kit-8 assay was used to detect the viability of HESCs. Related proteins were detected by qPCR and western blot. Result: The results indicated that TOB1 expression was upregulated in the secretory endometrial samples compared with the corresponding expression observed in the proliferative samples. The expression levels of TOB1 and Notch1 were markedly increased in E2P4-treated HESCs compared with those in the control cells. Treatment with E2P4 strongly suppressed the proliferation of HESCs and induced a G1-phase cell cycle arrest. These effects were abolished by knockdown of TOB1 or treatment with of the cells with the Notch inhibitor N-[N-(3,5-difluorophenacetyl)-1-alanyl]-S-phenylglycine t-butyl ester. Conclusions: Therefore, these findings highlighted an important role for TOB1/Notch signaling in E2P4-induced decidualization in HESCs, which may provide novel targets for improving the endometrial receptivity. [ABSTRACT FROM AUTHOR]

The potential for electrochemical conversion of bio-oil was overlooked for a long period due to the poor electrical conductivity and unclear reaction mechanism. This study aimed to provide an insight into bio-oil of electrochemical conversion mechanism and product distribution. In this study, using walnut shell bio-oil with enhanced electrical conductivity by ammonium carbonate as raw material, electrolysis experiments were carried out using different electrolysis times by constant current method (20 mA) in H-type electrolytic cell at a stable temperature (0 °C). The results showed that phenols, aldehydes, and lignin were copolymerized; meanwhile, unsaturated fatty acids such as oleic acid underwent decarbonylation and decarboxylation. The hydrogen-releasing electrode reaction also occurred at the cathode during the conversion process. Besides, the properties of products were characterized by elemental analysis, GC-TCD/FID, GC/MS, 1H NMR, FTIR, and TG-FTIR. Solid products were of possibility for application in new materials owing to containing copolymers with lignin structure, and gas products could be utilized as gas fuels with the combustible gas (H2, CO, CH4, and olefins) content as 79.24%. [ABSTRACT FROM AUTHOR]

The Stöber method was used to synthesize silicon sphere carriers with uniform size. The surface of the silicon sphere carrier was treated with 3-aminopropyltrimethoxysilane and 2-bromopropionyl bromide as atom transfer radical polymerization (ATRP) initiator and grafted with polyhydroxyethyl methacrylate (PHEMA) by ATRP. Bismuth nitrate was used as bismuth source to form polymer-metal complex with PHEMA. Sodium borohydride was used to reduce the bismuth ions in the composite material to metallic bismuth, and the metal bismuth on the surface of the composite material was oxidized in air atmosphere at 450 °C to obtain the inorganic–organic bismuth oxide composite. The morphology, elemental composition and photocatalytic degradation efficiency of Rhodamine B by bismuth oxide composite were characterized by various measurements. The TG and TEM results show that the composite material has good thermal stability, and Bi2O3 has very good dispersibility and stability in the prepared Bi2O3 composite. When the pH value is 4 with a catalyst dosage of 1.2 g/L, the degradation efficiency of Rhodamine B can reach 99.3% after 4 h of light irradiation, which is 24.2% higher than that of pure bismuth oxide. After 5 cycles, Bi2O3 composites still have a strong degradation effect with a degradation rate of 90.1% for Rhodamine B dye solution, which illuminates that the prepared Bi2O3 composite has good cyclic degradation performance. [ABSTRACT FROM AUTHOR]

This paper exhibits good example of high well-defined hollow silica spheres by using a low-cost sodium silicate precursor via a facile method. The N adsorption isotherm shows that this hollow structure leads to a high Brunauer-Emmett-Teller specific area of ca. 217.755 m g. Transmission electron microscopy and scanning electron microscopy images indicate that prepared hollow silica spheres have uniform morphology and narrow size distribution. Particle size analyzer measurement (polydispersity = 0.005; GSD = 1.073) also further confirms the fact that hollow silica spheres with high monodispersity have been successfully developed as expected. [ABSTRACT FROM AUTHOR]

A novel one-pot catalytic synthesis of 1-benzoylpyrene through acylation of pyrene with benzoic anhydride catalyzed by several heteropoly acids (HPAs) was investigated. Pure 1-benzoylpyrene was obtained and its structure was identified by GC/MS, FT-IR and H NMR spectra. Silica-supported phosphotungstic heteropoly acid (PW/SiO) was found to be the most active catalyst in the acylation. The yield and the selectivity of 1-benzoylpyrene were up to 62.5% and 100%, respectively. The effects of experimental parameters on the catalytic acylation reaction, and the possibility of reusability of PW/SiO catalyst were studied. PW/SiO catalyst is easily separable from the reaction mixture and reusable without loss of its activity. [ABSTRACT FROM AUTHOR]

Alkylation of anthracene with 2-chloropropane to 2-isopropylanthracene catalyzed by various Lewis acidic ionic liquids (ILs), such as [Emim]Cl-AlCl3, [Emim]Cl-FeCl3, [Emim]Cl-ZnCl2, [Bmim]Cl-AlCl3, and [Omim]Cl-AlCl3 ([Emim]+=1-ethyl-3-methylimidazolium cation, [Bmim]+=1-butyl-3-methylimidazolium cation, [Omim]+=1-octyl-3-methylimidazolium cation,), was investigated. [Emim]C1-A1C13 ionic liquid was found to be the most active catalyst in the alkylation. The yield of 2-isopropylanthracene was up to 74.5% and the selectivity of 2-isopropylanthracene was up to 82.9%. The [Emim]C1-A1C13 ionic liquid catalyst showed good catalytic activity after running for 6 times. Ease of product separation and the recycling performance of the ionic liquid catalyst is expected to contribute to the development of clean and environmentally friendly strategy for the synthesis of 2-isopropylanthracene. [ABSTRACT FROM AUTHOR]