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Herein, a reverse bias heterojunction NiCoS/NiCo-OH with mesopores as the positive electrode was constructed by interface engineering. During the process of charging, the application of a positive bias potential by the external circuit to the reverse bias heterojunction NiCoS/NiCo-OH enhances the accumulation of charges within the NiCoS nanosheets. Under the modulation of the built-in electric field at the interface, the mesoporous interface of NiCo-OH acts as a receiver, collecting charges from NiCoS nanosheets and forming a channel leading to efficient ion diffusion and charge transfer. The specific capacity of the NiCoS/NiCo-OH electrode is up to 406.5 mA h g–1 at 1 A g–1. It demonstrates ultrahigh rate performance, reaching 81.9% (50 A g–1) and 77.4% (100 A g–1). The hybrid supercapacitor NiCoS/NiCo-OH//FNG shows a high energy density of 51.3 W h kg–1 at 1650 W kg–1. Moreover, the capacity of the Zn||NiCoS/NiCo-OH battery reaches 419.1 mA h g–1cathode at 1 A g–1, and it can still maintain 73% (306.3 mA h g–1cathode) at 100 A g–1. [ABSTRACT FROM AUTHOR]

A novel boron‐containing novolac (triphenyl borate‐formaldehyde resin, TPBF) was synthesized. The structure, thermoplasticity, molecular weight, and molecular weight distribution of TPBF have been characterized with FT‐IR, melt viscosity, 13C NMR and GPC. The thermal stability of TPBF was investigated by TGA, indicating the thermal stability of TPBF was much better than that of normal novolac (phenol‐formaldehyde resin, PF). TPBFs with different molar ratios of formaldehyde to benzene ring in triphenyl borate (TPB) were also synthesized and compared for molecular size, polydispersity and thermal stability. Further, the thermal degradation kinetics of TPBFs and PF were studied by TGA using Madhusdanan‐Krishnan‐Ninan method and the activation energies were calculated at different degradation stages. It was found that the thermal degradations of TPBFs and PF are a multistage reaction and the degradation reactions in every stage follow the first order reaction mechanism. Finally, the activation energies of thermal degradations of novolac increase with the introduction of boron, the progress of degradation reaction as well as the increase of molar ratios. [ABSTRACT FROM AUTHOR]

The selective crystallization behaviours of amorphous boscalid (BOS), BOS monohydrate and acetone/ethyl acetate/ethanol/methanol solutions were explained and predicted by mid-frequency Raman difference spectroscopy analysis. The phase transition processes including solution to amorphous BOS, solution to BOS monohydrate, and amorphous BOS to Form I were explained, predicted and realized. Also, suitable preparation routes for different BOS phases with good purities were proposed. [ABSTRACT FROM AUTHOR]

Background: Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are of potential magnetic resonance imaging (MRI) contrast agents for tumor diagnosis. However, ultrasmall particle size or negative surface charge lead to relative short half-life which limit the utilization of USPIO for in vivo MRI contrast agents. Methods: Superparamagnetic Fe3O4 nanoparticles coated with polyacrylic acid (PAA)were synthetized, and modified by 3-amino propanol and 3-diethyl amino propyl amine. The characteristics of superparamagnetic Fe3O4 nanoparticles were investigated through transmission electron microscopy, X-ray diffraction analysis, Zata potential analysis, thermogravimetric analysis, and relaxation properties analysis. Magnetic resonance imaging animal experiment was performed. Results: The synthetized nanoparticles were irregular spherical, with small particle size, few agglomeration, and good dispersion in water. After modification, the potential fluctuation of nanoparticles was small, and the isoelectric point of nanoparticles changed to high pH. After 3-amino propanol modification, the weight loss of the curve from 820 to 940 °C was attributed to the decomposition of 3-amino propanol molecules on the surface. The T1 relaxation rate of nanoparticles changed little before and after modification, which proved that the modification didn't change the relaxation time. Brighter vascular images were observed after 3-amino propanol modification through measurement of magnetic resonance tumor imaging. Conclusion: These data indicated the Fe3O4 nanoparticles modified by 3-amino propanol should be a better contrast agent in the field of magnetic resonance tumor imaging. [ABSTRACT FROM AUTHOR]

Abstract: Hybrid materials (Cu–C60) formed by C60 decorating the surface of copper clusters were prepared through pulsed laser ablation at the interface between copper solid target and a flowing fullerene solution of hexane. UV–Vis shows that the feature absorption intensity of C60 in the copper–fullerene–hexane sol decreases, and the increased absorption band of copper-cluster sol can also be found between 190 nm and 240 nm. Element analysis indicates that copper clusters in the sample (Cu–C60) are decorated mainly by C60. HRTEM identified that copper clusters are decorated by C60; XRD reveals that the diffraction peaks of the sample have lower value and broader width than pure copper, indicating the surface of copper clusters is decorated by an amorphous material. Magnetism tested by VSM indicated that the sample has one Curie point at 203 K, suggesting that high temperature, high pressure and very rapidly cooled microarea in the method of PLA/ISFL are of importance in affecting the magnetic property of the hybrid material. [Copyright &y& Elsevier]

Magnetic nonviral gene vectors were in situ prepared in the presence of ferrous salts and hyperbranched poly(ethylenimine)s (HPEI) with different molecular weights. HPEI, one of the most promising nonviral vectors, was not only utilized as the nanoreactor and stabilizer to prepare magnetic nanoparticles, but also skillfully used as a base supplier to avoid introducing alkali hydroxide or ammonia. Magnetic nonviral gene vectors with various magnetite contents and saturation magnetizations were obtained by changing the weight ratio of HPEI to FeSO(4).7H(2)O and the molecular weight of HPEI. MTT assays suggested that the resulting magnetite/HPEI gene vectors had lower cytotoxicity compared with pure HPEI. The magnetite/HPEI nonviral gene vectors were used for magnetofection. It was found that the luciferase expression level mediated by magnetite/HPEI in COS-7 cells under a magnetic gradient field was approximately 13-fold greater than that of standard HPEI transfection.