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Silver nanodisks (AgNDs) have been successfully synthesized by using ferric chloride as an auxiliary agent in the presence of polyvinylpyrrolidone and

The wide application of CsPbI3 nanocrystals (NCs) is limited due to their poor phase stability. We reported that Mn2+-CsPbI3 NCs have better optical performance and phase stability. With a suitable Mn/Pb ratio (5.0%), Mn2+-doped α-CsPbI3 NCs exhibited the best stability under UV irradiation, ethanol addition, and heating. Under UV irradiation and addition of ethanol, photoluminescence (PL) intensities of CsPbI3 NCs could be only preserved up to 35% (22 min UV irradiation) and 10% (ethanol addition), respectively, whereas, Mn2+-doped CsPbI3 (5.0%) exhibited much improved stability, and their intensities could be preserved up to 70% (22 min UV) and 58% (ethanol), respectively. It should be noted that crystal-phase stability could be maintained at least 7 h even at 120 °C. We believe that the improved stability in extreme conditions for α-CsPbI3 NCs can be further applied to optoelectronic devices.

Exhaled breath analysis by nanosensors is a workable and rapid manner to diagnose lung cancer in the early stage. In this paper, we proposed Al-doped MoSe2 (Al-MoSe2) as a promising biosensor for sensing three typically exhaled volatile organic compounds (VOCs) of lung cancer, namely, C3H4O, C3H6O, and C5H8, using the density functional theory (DFT) method. Single Al atom is doped on the Se-vacancy site of the MoSe2 surface, which behaves as an electron-donor and enhances the electrical conductivity of the nanosystem. The adsorption and desorption performances, electronic behavior, and the thermostability of the Al-MoSe2 monolayer are conducted to fully understand its physicochemical properties as a sensing material. The results indicate that the Al-MoSe2 monolayer shows admirable sensing performances with C3H4O, C3H6O, and C5H8 with responses of -85.7, -95.6, and -96.3%, respectively. Also, the desirable adsorption performance and the thermostability endow with the Al-MoSe2 monolayer with good sensing and desorbing behaviors for the recycle detection of three VOCs. We are hopeful that the results in this paper could provide some guidance to the experimentalists fulfilling their exploration in the practical application, which can also broaden the exploration of transition-metal dichalcogenides (TMDs) in more fields as well.

Deep eutectic solvents (DESs) play important roles in the extraction of active constituents in traditional Chinese medicine. Ultrasound-assisted DES has been used to extract flavonoids from Scutellaria baicalensis. Using the contents of scutellarin, baicalin, baicalein, wogonoside, wogonin, and oroxylin A as quantitative indices, different kinds of DESs have been optimized for extraction and betaine/acetic acid has shown the highest yield. The Box-Behnken response surface method (RSM) was utilized to select the extraction conditions with the highest yields. The optimal extraction conditions were as follows: the molar ratio of betaine/acetic acid was 1:4, the water content was 40%, the solid/liquid ratio was 1:100 g/mL, the extraction temperature was 52 °C, and the extraction time was 23 min. Compared with traditional reflux extraction using 70% ethanol as the solvent, ultrasound-assisted DES has a shorter extraction time and higher yields. Furthermore, anti-inflammatory activities of the two extracts by ultrasound-assisted DES and reflux were compared using RAW264.7 cells and the methyl thiazolyl tetrazolium (MTT) method, and they showed equal anti-inflammatory activities. The results demonstrated that the ultrasound-assisted DES method for extraction of flavonoids from scutellariae radix is simple, green, efficient, and reproducible. This research provides good method guides for the rapid and efficient extraction of flavonoids from natural sources.

In this letter, we perform a first-principles study on the adsorption performance of the InP3 monolayer upon three SF6 decomposed species, including SO2, SOF2, and SO2F2, to investigate its potential as a resistance-type, optical or field-effect transistor gas sensor. Results indicate that the InP3 monolayer exhibits strong chemisorption upon SO2 but weak physisorption upon SO2F2. The most admirable adsorption behavior is upon SOF2, which provides a favorable sensing response (−19.4%) and recovery property (10.4 s) at room temperature as a resistance-type gas sensor. A high response of 180.7% upon SO2 and a poor one of −1.9% upon SO2F2 are also identified, which reveals the feasibility of the InP3 monolayer as a resistance-type sensor for SO2 detection with recycle use via a heating technique to clean the surface. Moreover, the InP3 monolayer is a promising optical sensor for SO2 detection due to the obvious changes in adsorption peaks within the range of ultraviolet and is a desirable field-effect transistor sensor for selective and sensitive detection of SO2 and SOF2 given the evident changes of QT and Eg under the applied electric field.

Using a first-principles theory, the structural and electronic behaviors of noble metal atom (Rh, Pd, and Pt)-decorated N3-CNTs were investigated. Meanwhile, the adsorption behavior of CO and CH4 molecules onto Rh-, Pd-, and Pt-decorated N3-CNTs was studied as well to exploit their potential applications. Results indicate that noble metal atoms are likely to be adsorbed on the N3 center of pyridine-like N3-CNTs under electrophilic attack. Moreover, the noble metal-embedded N3 group would provide CNTs with enhanced performance for gas adsorption compared with noble metal-embedded surfaces because of the improvement of chemical activity and electron mobility in our proposed configurations. The findings in this report would be beneficial for exploiting a possible adsorbent for CO scavenging with excellent adsorbing ability and a possible sensor for CH4 detection with good sensitivity and recovery behavior.

We carried out a density functional theory study to investigate the adsorption behavior of four kinds of SF6 decomposed products over the ZnO(1010) surface. The effects of O and Zn vacancies on the surface were also considered. For perfect ZnO(1010) surface, the adsorption of SO2 and H2S exhibits stronger chemical interactions compared to the adsorption of SOF2 and SO2F2. For SO2 and H2S adsorption, there may exist new chemical bond formation between the molecule and the surface and the H2S molecule experiences one H-S broken bond. The introduction of O vacancy cannot obviously enhance the chemical interactions between these four molecules and the surface. However, the Zn vacancy on the surface can significantly elevate the chemical interactions between SO2/H2S and the surface. The two-coordinated O atom (O2c) on the surface plays an important role. For SO2 and H2S adsorption, the S atom in SO2 or H2S tends to bond to the O2c atom, bringing much larger adsorption energy compared to the adsorption over the perfect ZnO(1010) surface. This work can provide a basis for surface modification of ZnO in applications to detecting SF6 decomposed products by theoretical evaluation.

The potential therapeutic application of oligonucleotides (ONs) that selectively suppress target genes through antisense and RNA interference mechanisms has attracted great attention. The clinical applications of ONs have overcome multiple obstacles and become one of the most active areas for the development of novel therapeutics. To achieve efficient and specific cellular internalization, conjugation of a variety of functional groups to ONs has been the subject of intensive investigations over the past decade. Among them, a promising liver-targeted N-acetylgalactosamine (GalNAc) ligand has been evaluated in multiple preclinical and clinical trials for improving the cellular uptake and tissue specific delivery of ONs. GalNAc-based delivery relies on the fact that liver hepatocytes abundantly and specifically express the asialoglycoprotein receptor that binds and uptakes circulating glycoproteins via receptor-mediated endocytosis. In recent years, encouraging progress has been made in the field of GalNAc conjugates. This review aims to provide an overview of GalNAc-mediated liver-targeted delivery of small interfering RNA and antisense oligonucleotides, and the immense effort as well as recent advances in the development of GalNAc-conjugated agents are described.

Essential oil (Eo) from the Citrus reticulata peel has been widely used, and its adhesive effect on polystyrene (PS) was found accidentally. To analyze the essential oils of C. reticulata cv. Shatangju (CrspEos), the extraction of these oils by steam distillation was optimized using the response surface method. The chemical composition of CrspEos was analyzed by gas chromatography–mass spectrometry. Then, the adhesive effect of these essential oils on PS was evaluated. The adhesion area, the influence of adhesion on the thickness of the essential oil on the materials, the effect of adhesion on the transmittance of PS, the strength of adhesion point, and specificity of adhesion were determined. The optimum extraction conditions resulting in the extraction yield of 47.37 μL g–1 were a ratio of liquid-to-solid of 8.94:1, a soaking time of 199.45 min, and an extraction time of 138.71 min. The major component in the essential oils was d-limonene (56.66%), followed by myrcene (6.62%). CrspEos presented a specific adherence effect on PS without influencing the thickness and transmittance of PS but with stronger tenacity than the parent material. CrspEos can be used as an environmentally friendly specific adhesive for PS.

We carried out a density functional theory study to investigate the adsorption behavior of four kinds of SF6 decomposed products over the ZnO(101̅0) surface. The effects of O and Zn vacancies on the surface were also considered. For perfect ZnO(101̅0) surface, the adsorption of SO2 and H2S exhibits stronger chemical interactions compared to the adsorption of SOF2 and SO2F2. For SO2 and H2S adsorption, there may exist new chemical bond formation between the molecule and the surface and the H2S molecule experiences one H–S broken bond. The introduction of O vacancy cannot obviously enhance the chemical interactions between these four molecules and the surface. However, the Zn vacancy on the surface can significantly elevate the chemical interactions between SO2/H2S and the surface. The two-coordinated O atom (O2c) on the surface plays an important role. For SO2 and H2S adsorption, the S atom in SO2 or H2S tends to bond to the O2c atom, bringing much larger adsorption energy compared to the adsorption over the perfect ZnO(101̅0) surface. This work can provide a basis for surface modification of ZnO in applications to detecting SF6 decomposed products by theoretical evaluation.