Owing to the requirement for environmental protection, water-based coatings have become a significant trend in the development of coatings. The water-based epoxy curing agent has also become a hot ...research topic. In this study, a B-A-B epoxy compound with a long hydrophobic alkyl chain connected to the intermediate nitrogen atom was synthesized at both ends of a molecule using ethylene glycol diglycidyl ether and 3,4-dimethoxyaniline as raw materials. Subsequently, the epoxy compound was sealed with triethylenetetramine. A nonionic, water-based epoxy resin curing agent with amino groups at both ends of the molecule was prepared. The target product structure was confirmed by infrared spectroscopy (IR), Mass spectrum (MS), and Nuclear magnetic resonance hydrogen spectroscopy (1H-NMR). Additionally, through three factors and three levels of orthogonal experimental design, the optimum experimental conditions were confirmed, the optimum yield was 82.83%. The thermogravimetric analysis (TGA) indicated that the monomer exhibited a significant weight loss in the temperature range of 320–450°C. The pencil hardness, flexibility, and impact resistance of the waterborne epoxy resin coating film prepared by the non-ionic water-based epoxy curing agent reached or exceeded those of similar products at China and foreign countries.
Dimethyl sulfoxide (DMSO) with sodium carbonate (Na2CO3) is an effective catalyst system for C60 cyclopropanation through the Bingel reaction. Various bromomalonic esters, brominated β-keto esters, ...brominated 1,3-diketones, and other bromo-substituted active methylene compounds can react with C60 in the presence of DMSO and Na2CO3 to achieve excellent yields of the corresponding methanofullerenes at 10 °C. Moreover, this proposed methodology has been also employed successfully to functionalize 70fullerene, single-walled carbon nanotubes (SWNTs), and graphene. This protocol is beneficial because it involves short reaction time, high yield, and a simple procedure. Additionally, this method does not need a strong base, such as sodium hydride and 1,8-diazabicyclo5,4,0undec-7-ene, because inexpensive Na2CO3 can be the catalyst.
In this study, a series of novel pirfenidone derivatives were designed and synthesized, and their activities against pulmonary fibrosis were evaluated. The structures of all the derivatives were ...characterized by
1
H and
13
C nuclear magnetic resonance and high-resolution mass spectrometry spectra. A preliminary investigation of their bioactivity demonstrated that all the target compounds exhibited different degrees of activity against pulmonary fibrosis and that the activities of most derivatives were markedly superior to that of pirfenidone.
A series of chiral ligands were synthesized using chloramphenicol base as starting materials. These ligands were applied to the asymmetric catalytic reactions of terminal alkynes with aldehydes to ...obtain a propargyl alcohol product in high yield (80–94%) with excellent enantioselectivities (82–96%).
The (1S, 2S)‐1‐phenyl‐2‐(1‐piperidyl)‐1,3‐propanediol ligand was applied to the asymmetric catalytic reactions of terminal alkynes with aldehydes to obtain a propargyl alcohol product in high yield (80–94%) with excellent enantioselectivities (82–96%).
Recently, there has been significant interest in the utilization of indium-doped cadmium sulfide (CdS) for the detection of chloramphenicol (CAP) in food samples due to its exceptional performance. ...The objective of this research is to develop a simple, rapid, and highly sensitive sensor for CAP detection. CdS possesses remarkable characteristics as a semiconductor material, including a large specific surface area, abundant pore structure, and excellent electrical conductivity. The electrochemical properties of glassy carbon electrodes (GCE) were comprehensively investigated both in their pristine state and when modified with CdS/GCE, CdIn2S4/GCE, Cd1.5In2S4.5/GCE, and Cd2In2S5/GCE. The surface areas of the modified electrodes CdIn2S4/GCE, Cd1.5In2S4.5/GCE, and Cd2In2S5/GCE were measured to be 0.08 cm2, 0.097 cm2, and 0.25 cm2, respectively. Five replicate samples using the optimized proportioned electrode Cd2In2S5/GCE resulted in a response error below 5%. These results indicate that the composite demonstrates exceptional conductivity and reproducibility while maintaining satisfactory sensitivity and high specificity. The proposed sensor based on Cd2In2S5/GCE exhibited an impressive dynamic linear range from 10 nmol/L to 20 μmol/L with an exceptionally low detection limit of 3.8 nmol/L and remarkable sensitivity of 0.38 μA μm−1 cm−2. This sensor successfully quantified CAP in water samples with a satisfactory recovery rate ranging from 99.5% to 100.3%, accompanied by an RSD below 7.6%. Consequently，this developed electrochemical sensor presents itself as the optimal choice for simultaneous determination of CAP in both food and water samples.
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•The Cd2In2S5/GCE exhibited high repeatability and stability, along with excellent anti-interference ability.•An appreciably lower detection limit (3.8 nnol/L) and good sensitivity (0.38 μA μm−1 cm−2).•It shows that this method has a good application prospect in the pretreatment of wastewater containing CAP.
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•The NixCoyP like pinecone electrocatalyst is synthesized by a reflux condensation method.•NiCo2P showed significant activity on oxygen evolution reaction (OER).•NiCo2P also shows ...impressive long term stability and excellent electrical conductivity.•The Co3+ ions can adjust the electronic structure and increase the active sites.
Synthesis of bimetallic phosphide like Pine cone efficient electrocatalyst for the development of water electrolyzers is of significant interest. Herein, NixCoyP catalyst was synthesized via Condensation reflux and phosphating process, and it has a defect rich nanosheet like morphology. The special morphology provided more active toward the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). NiCoP delivers the current density of 10 mA/cm2 for HER at an overpotential of 226 mV in alkaline. NiCo2P is also highly active toward OER and requires 154 mV to attain 10 mA/cm2. The NiCo2P delivers 10 mA/cm2 current density at a cell voltage of 1.49 V and retains 75% of its initial current density even after 12 h of continuous electrolysis.
Diosgenin, a component separated from Dioscorea plants, is an important starting material for steroid hormone drugs and semisynthetic steroids. In the work, two series of diosgenin derivatives were ...designed, synthesized, and evaluated for their cellular anticancer activities. Most of the target compounds exhibited good inhibitory activities against four cell lines, Aspc-1 (human colon adenocarcinoma cells), H358 (human nonsmall cell lung cancer cells), HCT116 (human colorectal adenocarcinoma cells), and SW620 (human metastatic pancreatic cancer cells). Among them, the representative compound 2.2f exhibited 7.9–341.7-fold antiproliferative activities against the above-mentioned four cell lines compared with the lead compound diosgenin.
In this work, we report a novel cathode composed of three-dimensional intersected graphene nanoribbons skeleton decorated with RuO2 catalyst, where graphene nanoribbons are obtained by unzipping ...multi-walled carbon nanotubes. The graphene nanoribbons framework exhibits a three-dimensional intersected structure and a large specific surface area, leading to a higher capacity than multi-walled carbon nanotubes. The RuO2 introduced via a facile dropping method enhances the oxygen evolution reaction kinetics and obviously reduces the charge overpotential. More importantly, the Li–O2 battery with RuO2 decorated graphene nanoribbons cathode presents an excellent cycling stability of 424cycles at a curtailed capacity of 1000 mAh g−1, which can be attributed to the synergistic effect between the intersected band-like graphene and highly effective RuO2 particles. The Li2O2 deposited on graphene nanoribbons shows a totally different surface morphology compared with that on multi-walled carbon nanotubes due to the different structures of carbon substrates. This work provides a promising design of highly efficient air electrodes for high-performance Li–O2 batteries.
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•A 3D intersected graphene nanoribbons skeleton is prepared by chemical shear.•The ORR performance of the cell with GNRs is better than that with MWCNTs.•The battery with RuO2@GNRs shows an excellent cycling stability of 424cycles.•The deposition of Li2O2 shows two totally different morphologies on GNRs and MWCNTs.•The strip-like Li2O2 deposited on the quasi-1D GNRs obeys conformal growth mode.
In order to discover novel anti-pulmonary fibrosis agents, a series of novel pirfenidone derivatives were designed and synthesized. All compounds were investigated for their anti-pulmonary activity ...and characterized by
13
C and
1
H nuclear magnetic resonance and high-resolution mass spectrometry. Preliminary studies on their biological activity showed that all target compounds showed different degrees of inhibition on pulmonary fibrosis, and most of the derivatives were significantly better than pirfenidone.
In order to discover novel anti-pulmonary fibrosis agents, a series of novel pirfenidone derivatives were designed and synthesized.
The reactions of 60fullerene with benzyl chlorides and amino acids in chlorobenzene (PhCl) were investigated. Fulleropyrrolidines bearing ArCH moieties originating from the corresponding benzyl ...chlorides through C–Cl bond cleavage were obtained from these reactions. Use of PhCl/DMSO instead of PhCl as the solvent significantly improved the reaction efficiency. A detailed investigation of these reactions resulted in the discovery of other halides – such as allyl chloride, methallyl chloride, cinnamyl chloride, propargyl bromide, ethyl bromoacetate, bromoacetonitrile, bromomethane, bromopropane and bromobutane – that could also react with 60fullerene and amino acids to produce fulleropyrrolidines. This reaction could be an alternative to the Prato reaction for synthesizing fulleropyrrolidines when aldehydes are expensive or unavailable from commercial sources. A plausible reaction mechanism for product formation involving C–X bond cleavage in the halide to form the aldehyde is proposed.
Fulleropyrrolidines bearing ArCH moieties were obtained in reactions between C60, the appropriate benzyl chlorides, and amino acids. A detailed investigation of these reactions resulted in the discovery of other halides, such as allyl chlorides, propargyl bromides, ethyl bromoacetate, bromoacetonitrile, and alkyl bromides, that also reacted with C60 and amino acids to produce fulleropyrrolidines.
![Reactions of [60]Fullerene ...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/1434-193X/small "Reactions of [60]Fullerene with Halides and Amino Acids to Synthesize Fulleropyrrolidines")