Electrochemically Mediated Surface-Initiated Atom Transfer Radical Polymerization by ppm of CuII/Tris(2-pyridylmethyl)amine.

Atom transfer radical polymerization (ATRP) is one of the most widely used methods for modifying surfaces with functional polymer films and has received considerable attention in recent years. Here, we report an electrochemically mediated surface-initiated ATRP to graft polymer brushes onto solid substrates catalyzed by ppm amounts of CuII/TPMA in water/MeOH solution. We systematically investigated the type and concentrations of copper/ligand and applied potentials correlated to the polymerization kinetics and polymer brush thickness. Gradient polymer brushes and various types of polymer brushes are prepared. Block copolymerization of 2-hydroxyethyl methacrylate (HEMA) and 3-sulfopropyl methacrylate potassium salt (PSPMA) (poly(HEMA-b-SPMA)) with ultralow ppm eATRP indicates the remarkable preservation of chain end functionality and a pronounced "living" characteristic feature of ppm-level eATRP in aqueous solution for surface polymerization.

Halogen-Free Functional Quaternary Ammonium-Based Ionic Liquid as an Ecofriendly Corrosion Inhibitor for Q235 Steel in Acids.

A halogen-free quaternary ammonium-based ionic liquid functionalized with benzotriazole, BTA-16-BTA, was synthesized. Its anticorrosion effects on Q235 steel were evaluated in two different acids (6 M HCl or 1 M H3PO4) by weight loss and electrochemical tests. BTA-16-BTA shows the best performance at 30 °C with the highest inhibition efficiencies of 98.84% in 6 M HCl and 96.40% in 1 M H3PO4. The adsorption behavior of BTA-16-BTA molecules on Q235 steel in HCl solution obeys the Langmuir isotherm with an adsorption energy of about -40 kJ·mol-1, which implies chemisorption. Quantum chemistry calculation indicates that the chemical adsorption originated from the injection of π-electrons from inhibitor molecules into empty 3d orbitals of Fe atoms. The tight adsorption of inhibitor molecules and associated dehydration of the steel surface promoted the corrosion inhibition in HCl solutions. In H3PO4 solutions, passivation by phosphate anions and adsorption of inhibitor molecules contributed synergistically to the excellent anticorrosion performance.

Multifunctional Nanoparticles in Precise Cancer Treatment: Considerations in Design and Functionalization of Nanocarriers.

Nanotechnology has revolutionized cancer treatment in both diagnosis and therapy. Since the initial application of nanoparticles (NPs) in cancer treatment, the main objective of nanotechnology was developing effective nanosystems with high selectivity and specificity for cancer treatment and diagnosis. To achieve this, different encapsulation and conjugation strategies along with surface functionalization techniques have been developed to synthesize anticancer drugs loaded NPs with effective targeting to specific tumor cells. The unique physicochemical attributes of NPs make them promising candidates for targeted drug delivery, localized therapies, sensing, and targeting at cellular levels. However, a nanosystem for localized and targeted cancer managements should overcome several biological barriers and biomedical challenges such as endothelial barriers, blood brain barrier, reticuloendothelial system, selective targeting, biocompatibility, acute/chronic toxicity, tumor-targeting efficacy. The NPs for in vivo applications encounter barriers at system, organ, and the cellular level. To overcome these barriers, different strategies during the synthesis and functionalization of NPs should be adapted. Pharmacokinetics and cellular uptake of NPs are largely associated with physicochemical attributes of NPs, morphology, hydrodynamic size, charge, and other surface properties. These properties can be adjusted during different phases of synthesis and functionalization of the NPs. This study reviews the advances in targeted cancer treatment and the parameters influencing the efficacies of NPs as therapeutics. Different strategies for overcoming the biological barriers at cellular, organ and system levels and biomedical challenges are discussed. Moreover, the applications of NPs in preclinical and clinical practice are reviewed.

Study on ultrasound-assisted precipitation for preparing Ni/Al2O3 catalyst.

With the rapid development of oil hydrogenation industry, the development of oil hydrogenation catalyst has also become a research hotspot. In this paper, ultrasound-assisted precipitation technique is used to prepare Ni/Al2O3 catalyst. The effect of ultrasonic output power on catalyst performance is investigated. The prepared catalyst is applied to the hydrogenation reaction of castor oil. It is found that the prepared catalyst shows the best hydrogenation performance when ultrasonic output power, frequency and ultrasonic treatment time are 80 W, 40 kHz and 600 min respectively. It also indicates that ultrasound-assisted precipitation technique can reduce the particle size and increase the specific surface area of Ni/Al2O3 catalyst so that its activity is improved. In addition, six important elements that should be considered in the development of industrial oil refining catalysts are discussed, and the effects of these factors on the catalyst performance are discussed. Finally, new way for improving catalyst performance is given, and the application of some new materials and methods in oil refining is introduced.

Preparing copper catalyst by ultrasound-assisted chemical precipitation method.

In this paper, preparing copper catalyst by ultrasound-assisted chemical precipitation method is investigated. The used equipment is JP-020 ultrasonic cleaner, power and frequency are 180 W and 40 kHz respectively. Under the action of ultrasound, CuSO4·5H2O is reduced by ascorbic acid to obtain copper. The products are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and catalytic performance test. The results show that the morphology of copper products is rod-like and irregular granular. Copper catalyst has good catalytic oxidation performance for dyes methylene blue, crystal violet, alizarin red and Rhodamine B. The catalytic efficiency of 10 mg catalyst copper to 6 mg/L methylene blue reaches 98.1%, and the catalytic efficiency of the catalyst increases with the increase of catalyst dosage and the decrease of dye solution concentration. In addition, the new preparation techniques for Cu-based catalysts based on coprecipitation method are compared. Finally, the development trend of the new technology of copper-based catalyst preparation based on coprecipitation method is pointed out.

Rapid analysis of phthalates in beverage and alcoholic samples by multi-walled carbon nanotubes/silica reinforced hollow fibre-solid phase microextraction.

A novel procedure based on multi-walled carbon nanotubes (MWCNTs)/silica reinforced hollow fibre solid-phase microextraction combined with gas chromatography-mass spectrometry has been developed to analyse trace phthalate acid esters in beverage and alcoholic samples. Because of their excellent adsorption capability towards hydrophobic compounds, functionalized MWCNTs, acting as solid-phase sorbent, were co-deposited with silica particles in the pores of polypropylene hollow fibre through a layer-by-layer self-assembly technique. The parameters influencing the extraction efficiency, such as pH values and ionic strength of sample solution, extraction time, temperature and desorption solvent were optimised. Recoveries for phthalates at spiking levels in different matrices were satisfactory (between 68% and 115%). Moreover, the results were further confirmed by comparing them with those obtained using a solvent extraction method according to the national standard of China.