Incorporation and solidification mechanism of manganese doped cement clinker

Using municipal and industrial solid waste as a substitute raw material and fuel in cement rotary kiln co-processing is considered an economic and environmentally friendly alternative to the use of traditional fuels. However, the presence of heavy metals in solid waste is a growing concern in the cement rotary kiln co-processing technique. The solidification mechanism of heavy metals in cement clinker is directly related to their stabilization. Cement clinkers doped with manganese oxide (MnO2: 0.0%–5.0% wt%) were prepared in a laboratory to investigate the impacts of extrinsic Mn on cement clinker calcination. The insignificant changes in X-ray diffractometer patterns indicated that the fixed Mn had little influence on the mineral lattice structure. Raman spectra and X-ray photoelectron spectroscopy revealed the transformation of the silicate phase when the Mn dose was increased. Moreover, the satisfactory solidification ratio confirmed the incorporation of Mn in the cement clinker. These results provided evidence of the influence rule of Mn in the cement clinker calcination process. Furthermore, Raman spectroscopy showed great potential for the qualitative and semi-quantitative analysis of the cementitious materials derived from cement rotary kiln co-processing. These results will be important for the further development of green cement manufacturing technology

Green synthesis of Ag nanoparticles using elm pod polysaccharide for catalysis and bacteriostasis

The green synthesis of silver nanoparticles (Ag NPs) for catalysis and biological applications has gained great interest. Natural elm pods are a type of food that possesses anti-inflammatory and pain-relieving effects. In this study, elm pod polysaccharide (EPP) was extracted from elm pods using hot water extraction for the first time. Biocompatible EPP-stabilized silver nanoparticles (EPP-Agn NPs) were prepared by using a green synthesis method. The EPP-Ag25 NPs had a hydrodynamic size of 40.9 nm and a highly negative surface charge of −27.4 mV. Furthermore, EPP-Ag25 NPs exhibited high catalytic activity for the reduction of 4-nitrophenol, and the catalytic reaction followed a pseudo-first order kinetic equation. More importantly, the inhibition rate of EPP-Ag25 NPs on Escherichia coli was 71 % when samples were treated with an 808 nm laser. Besides, EPP-Agn NPs effectively inhibited the proliferation of tumor cells irradiated by an 808 nm laser. The improved performance of EPP-Agn NPs was due to the good stability of EPP. Taken together, EPP-Agn NPs had good stability, catalytic activity, antibacterial and antitumor ability under laser irradiation. EPP is a good stabilizer for many nanoparticles which have broad applications in the field of catalysis and biomedicine in the future.</p

Zwitterionic sulfhydryl Sulfobetaine stabilized platinum nanoparticles for ernhanced Dopamine detection and antitumor ability

Herein, three kinds of molecules were used to modify the surface of platinum nanoparticles (Pt NPs) to tune their surface charge. Zwitterionic thiol-functionalized sulfobetaine (SH-SB) stabilized Pt NPs (SH-SB/Pt NPs) had the highest oxidase activity and peroxidase activity in the prepared platinum nanozymes due to the generation of reactive oxygen species. In addition, a colorimetric dopamine detection method was established based on the peroxidase activity of SH-SB/Pt NPs. This method had a wide range (0-120 μM), a low detection limit (0.244 μM), and high specificity. More importantly, SH-SB/Pt NPs displayed little hemolysis and good stability in the presence of proteins. SH-SB/Pt NPs demonstrated high cytotoxicity in vitro and good antitumor ability in vivo, which was attributed to the photothermal conversion ability of SH-SB/Pt NPs and the generation of reactive oxygen species in the acidic environment. The surface modification of nanozymes using zwitterionic molecules opens a new method to improve the catalytic activity and antitumor ability of nanozymes. </p

Vancomycin-Stabilized Platinum Nanoparticles with Oxidase-like Activity for Sensitive Dopamine Detection

The development of efficient, reliable, and sensitive dopamine detection methods has attracted much attention. In this paper, vancomycin-stabilized platinum nanoparticles (Van-Ptn NPs, n = 0.5, 1, 2) were prepared by the biological template method, where n represented the molar ratio of vancomycin to Pt. The results show that Van-Pt2 NPs had oxidase-like activity and peroxidase-like activity, and the mechanism was due to the generation of reactive oxygen 1O2 and OH. Van-Pt2 NPs exhibited good temperature stability, storage stability, and salt solution stability. Furthermore, Van-Pt2 NPs had almost no cytotoxicity to A549 cells. More importantly, the colorimetric detection of DA in human serum samples was performed based on the oxidase-like activity of Van-Pt2 NPs. The linear range of DA detection was 10–700 μM, and the detection limit was 0.854 μM. This study establishes a rapid and reliable method for the detection of dopamine and extends the application of biosynthetic nanoparticles in the field of biosensing

Zwitterionic Sulfhydryl Sulfobetaine Stabilized Platinum Nanoparticles for Enhanced Dopamine Detection and Antitumor Ability

Herein, three kinds of molecules were used to modify the surface of platinum nanoparticles (Pt NPs) to tune their surface charge. Zwitterionic thiol-functionalized sulfobetaine (SH-SB) stabilized Pt NPs (SH-SB/Pt NPs) had the highest oxidase activity and peroxidase activity in the prepared platinum nanozymes due to the generation of reactive oxygen species. In addition, a colorimetric dopamine detection method was established based on the peroxidase activity of SH-SB/Pt NPs. This method had a wide range (0–120 μM), a low detection limit (0.244 μM), and high specificity. More importantly, SH-SB/Pt NPs displayed little hemolysis and good stability in the presence of proteins. SH-SB/Pt NPs demonstrated high cytotoxicity in vitro and good antitumor ability in vivo, which was attributed to the photothermal conversion ability of SH-SB/Pt NPs and the generation of reactive oxygen species in the acidic environment. The surface modification of nanozymes using zwitterionic molecules opens a new method to improve the catalytic activity and antitumor ability of nanozymes