Swainrivers4821
For comparative catalytic studies, the complex [Li6(LPr)2(H2O)2]·hexane (9 hexane), where LPr2H2 = 1,3-di-n-propyloxycalix[4]areneH2, was also prepared. The molecular crystal structures of 1-9 are reported, and their ability to act as catalysts for the ring opening (co-)/polymerization (ROP) of the cyclic esters ε-caprolactone, δ-valerolactone, and rac-lactide has been investigated. In most of the cases, complex 6 outperformed the other systems, allowing for higher conversions and/or greated polymer M n.Pure NiO nanofibers and the In2O3-NiO one-dimensional heterogeneous nanofibers were prepared by electrospinning, and the gas sensing properties to acetone were also investigated. Material characterization proved that the heterogeneous nanofibers were composed of In2O3 and NiO, and the nanofibers exhibited an enhanced sensitivity to acetone. At the optimal working temperature, the response of In2O3-NiO nanofibers to 50 ppm acetone was more than 10 times higher than that of pure NiO nanofibers. The minimum detection limit of the heterogeneous nanofibers reached 10 ppb, while the pure NiO nanofibers only reached 100 ppb. Among acetone and the comparison gases (methanol, ethanol, triethylamine, ethyl acetate, and benzene), the heterogeneous nanofibers achieved the highest response to acetone. In addition, the heterogeneous nanofibers exhibited an improved response-recovery rate and good long-term stability. These results indicated that the In2O3-NiO one-dimensional heterogeneous nanofibers have great potential in low-concentration acetone detection. Combined with the material properties, the mechanism of the enhanced sensing properties was discussed in detail for the In2O3-NiO heterogeneous nanofibers.MicroRNAs (miRNAs) play a pivotal role in cellular functions and in the development and progression of cancer. Precise quantification of miRNAs from different clinical samples is a challenging but necessary endeavor that is largely neglected by many emerging fluorescence technologies. Herein, we propose here a novel miRNA detection method through a designed tetrahedral probe and DSN enzyme for attached signal amplification. The highlights of the method are calculated as (i) the tetrahedral probe induced a much higher transfection efficiency than normal probes; (ii) the DSN enzyme-based cleavage ensures amplification and thus leads to a high detection sensitivity. In all, we believe that the proposed method could greatly improve the sensitivity of intracellular miRNA imaging methods and contribute to the fundamental research and prognosis of cancer.In understanding the catalytic efficacy of silver (Ag0) and gold (Au0) nanoparticles (NPs) on glass-ceramic (GC) crystallization, the microstructure-machinability correlation of a SiO2-MgO-Al2O3-B2O3-K2O-MgF2 system is studied. The thermal parameters viz., glass transition temperature (T g) and crystallization temperature (T c) were extensively changed by varying NPs (in situ or ex situ). Tc was found to be increased (T c = 870-875 °C) by 90-110 °C when ex situ NPs were present in the glass system. Under controlled heat-treatment at 950 ± 10 °C, the glasses were converted into glass-ceramics with the predominant presence of crystalline phase (XRD) fluorophlogopite mica, [KMg3(AlSi3O10)F2]. Along with the secondary phase enstatite (MgSiO3), the presence of Ag and Au particles (FCC system) were identified by XRD. A microstructure containing spherical crystallite precipitates (∼50-400 nm) has been observed through FESEM in in situ doped GCs. An ex situ Ag doped GC matrix composed of rock-like and plate-like crystallites mostly of size 1-3 μm ensured its superior machinability. Vicker's and Knoop microhardness of in situ doped GCs were estimated within the range 4.45-4.61 GPa which is reduced to 4.21-4.34 GPa in the ex situ Ag system. Machinability of GCs was found to be in the order, ex situ Ag > ex situ Au ∼ in situ Ag > in situ Au. Thus, the ex situ Ag/Au doped SiO2-MgO-Al2O3-B2O3-K2O-MgF2 GC has potential for use as a machinable glass-ceramic.Honey is a high-value, globally consumed, food product featuring a high market price strictly related to its origin. Moreover, honey origin has to be clearly stated on the label, and quality schemes are prescribed based on its geographical and botanical origin. Therefore, to enhance food quality, it is of utmost importance to develop analytical methods able to accurately and precisely discriminate honey origin. In this study, an all-time scientometric evaluation of the field is provided for the first time using a structured keyword on the Scopus database. The bibliometric analysis pinpoints that the botanical origin discrimination was the most studied authenticity issue, and chromatographic methods were the most frequently used for its assessment. Based on these results, we comprehensively reviewed analytical techniques that have been used in honey authenticity studies. SU11274 Analytical breakthroughs and bottlenecks on methodologies to assess honey quality parameters using separation, bioanalytical, spectroscopic, elemental and isotopic techniques are presented. Emphasis is given to authenticity markers, and the necessity to apply chemometric tools to reveal them. Altogether, honey authenticity is an ever-growing field, and more advances are expected that will further secure honey quality.Because of the advantages of a uniform distribution of reinforcing particles and in situ preparation, in situ precipitation has become an important way to prepare magnetic and other smart hydrogels. An important step in this process is to immerse hydrogels in alkaline solution to implant magnetic particles. Previous studies generally have ignored the effect of this process on the network structure and mechanical properties of hydrogels. In this study, we immersed polyvinyl alcohol (PVA) hydrogel samples in sodium hydroxide solutions of different concentrations to study changes in mechanical properties, such as stress-strain relationship, self-recovery, and fracture failure. The results showed that after the immersion process, the hydrogel's tensile and compressive properties changed significantly, and the failure behavior changed from brittle fracture to ductile fracture. Through a microscopic mechanism, the alkaline solution caused a high degree of phase separation and crystallization within the polymer network, thereby changing the PVA hydrogel network from a single phase to a multiphase. Hence, we used a continuous multiphase network model with a certain probability distribution to describe this tensile behavior. This model well described the stress-strain relationship of the hydrogel from stretching to fracture and revealed that the macroscopic failure corresponded to the peak of fracture distribution. Studies have shown that attention should be paid to the influence of the in situ precipitation on the mechanical properties, and the probabilistic multiphase network model can be used to predict the mechanical behavior of hydrogels with multiple phase separation.Cellulose nanocrystals (CNCs) are the most commonly used natural polymers for biomaterial synthesis. However, their low dispersibility, conductivity, and poor compatibility with the hydrophobic matrix hinder their potential applications. Therefore, we grafted sulfate half-ester and carboxylic functional groups onto CNC surfaces (S-CNC and C-CNC) to overcome these shortcomings. The effect of the dopants, surfactant ratios, and properties of CNCs on the thermal stability, conductivity, and surface morphology of polyaniline (PANI)-doped CNC nanocomposites were investigated through emulsion and in situ polymerization. The higher electrical conductivity and well-dispersed morphology of SCNC-PANI30 (1.1 × 10-2 S cm-1) but lower thermal stability than that of CCNC-PANI30 (T 0 189 °C) nanocomposites are highly related to dispersibility of S-CNCs. However, after 4-dodecylbenzenesulfonic acid (DBSA) was added, the conductivity and thermal stability of SCNC/PANI increased up to 2.5 × 10-1 S cm-1 and 192 °C with almost no particle aggregation because of the increase in charge dispersion. The proposed biodegradable, renewable, and surface-modified S-CNC and C-CNC can be used in high-thermal-stability applications such as food packaging, optical films, reinforcement fillers, flexible semiconductors, and electromagnetic materials.In this study, a bio-based soy protein adhesive derived from environmentally friendly and renewable enzymatic hydrolysis lignin (EHL), epoxidized soybean oil (ESO), and soy protein isolate (SPI), was successfully prepared. A novel biopolymer (EHL-ESO), as a multifunctional crosslinker, was firstly synthesized from modified EHL and ESO, and then crosslinked with soy protein isolate to obtain a bio-based soy protein adhesive. The structure, thermal properties, and adhesion performance of the obtained soy protein adhesives were determined by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and wet shear strength. The maximum degradation temperature of SPI/EHL-ESO adhesives (332-343 °C) was higher than that of the pristine SPI adhesive (302 °C). Moreover, plywood bonded by the modified adhesive reached a maximum wet shear strength value of 1.07 MPa, a significant increase of 101.8% from the plywood bonded by pristine SPI adhesive. The enhancements in the thermal stability and wet shear strength were attributed to the formation of a dense crosslinking network structure. This work not only highlights the potential to replace petroleum-based polymers, but also presents a green approach to fabricate fully bio-based soy protein adhesive for preparing all-biomass wood composite materials.We synthesised a new compound with four naphthyl groups in the upper rims of calix[4]arene (1). Compared to the monomer unit, compound 1 has redshifted absorption and fluorescence, together with high fluorescence quantum yield and long fluorescence lifetime, which is extremely rare because long fluorescence lifetime emission tends to reduce the quantum yield. Single-crystal X-ray analysis and quantum calculations in the S1 state revealed π-π through-space interactions between naphthalene rings.The present work reports the sonochemical synthesis of DBNO NC (dysprosium nickelate nanocomposite) using metal nitrates and core almond as a capping agent. In addition, the effects of the power of ultrasound irradiation were investigated. The BaDy2NiO5/Dy2O3 and BaDy2NiO5/NiO nanocomposites were synthesized with sonication powers of 50 and 30 W, respectively. The agglomerated nanoparticles were obtained using different sonication powers, including 15, 30, and 50 W. The results showed that upon increasing the sonication power, the particle size decreased. After characterization, the optical, electrical, magnetic, and photocatalytic properties of the NC were studied. The nanocomposites showed an antiferromagnetic behavior. In this study, the photocatalytic degradations of two dyes, AR14 and AB92, were investigated in the presence of DBNO NC. Furthermore, the effects of the amount of photocatalyst, the concentration of the dye solution, the type of organic dye, and light irradiation on the photocatalytic activity of the nanocomposite were studied.