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The aim of this study was to examine whether the substitution of the Lys linker with the aminooctanoic acid (Aoc) and polyethylene glycol (PEG) linker could substantially decrease the non-specific renal uptake of (99m)Tc-labeled Arg-Gly-Asp-conjugated α-melanocyte stimulating hormone (α-MSH) hybrid peptides.The RGD motif {Arg-Gly-Asp-DTyr-Asp} was coupled to [Cys(3,4,10), D-Phe(7), Arg(11)]α-MSH₃₋₁₃ via the Aoc or PEG₂ linker to generate RGD-Aoc-(Arg(11))CCMSH and RGD-PEG-(Arg(11))CCMSH. The biodistribution results of (99m)Tc-RGD-Aoc-(Arg(11))CCMSH and (99m)Tc-RGD-PEG₂-(Arg(11))CCMSH were examined in M21 human melanoma-xenografted nude mice.The substitution of Lys linker with Aoc and PEG₂ linker significantly reduced the renal uptake of (99m)Tc-RGD-Aoc-(Arg(11))CCMSH and (99m)Tc-RGD-PEG₂-(Arg(11))CCMSH by 58% and 63% at 2h post-injection. The renal uptake of (99m)Tc-RGD-Aoc-(Arg(11))CCMSH and (99m)Tc-RGD-PEG₂-(Arg(11))CCMSH was 27.93 ± 3.98 and 22.01 ± 9.89% ID/g at 2 h post-injection. (99m)Tc-RGD-Aoc-(Arg(11))CCMSH displayed higher tumor uptake than (99m)Tc-RGD-PEG₂-(Arg(11))CCMSH (2.35 ± 0.12 vs. 1.71 ± 0.25% ID/g at 2 h post-injection). The M21 human melanoma lesions could be clearly visualized by SPECT/CT using (99m)Tc-RGD-Aoc-(Arg(11))CCMSH as an imaging probe.The favorable effect of Aoc and PEG₂ linker in reducing the renal uptake provided a new insight into the design of novel dual receptor-targeting radiolabeled peptides.

A magnetic metal organic framework (MOF) composite was prepared. The composite was fabricated by incorporation of Fe3O4 nanoparticals with MOF. It was characterized and expected to offer a promising template for molecular immobilization and sensor fabrication because of its ordered structure and satisfying large specific surface area. The resulting composite was used to detect methyl parathion. Electrochemical measurements showed that the multifunctional composite of MOF provided an excellent matrix for the co-adsorption of methyl parathion. Owing to the ordered structure, the large surface area, excellent compatibility and magnetic property of the material, methyl parathion could be separated, accumulated and directly detected in the solution with high sensitivity. The differential pulse voltammetry (DPV) response was proportional to the concentration range from 5.00 × 10(-6) to 5.00 × 10(-3) g L(-1) with the detection limit of 3.02 × 10(-6) g L(-1). The experimental results can lead to a widespread use of electrochemical sensors to detect organophosphorous pesticides contaminates and other substances.

The surface oxygen distribution the active oxygen species for CO on the perovskite-type catalyst La1-xSrxCo1-xMnxO3 and its catalytic oxidation activity with CO as probe were investigated by means of XRD, TPD and XPS in a continuous flow microreactor. Results showed that different adsorbed oxygen species and lattice oxygen were distributed on the catalyst surface. Meanwhile, the surface lattice oxygen of the oxides was reacting in the course of CO oxidation. This leads to the conclusion that, when x=0.6, the catalyst shows the best oxidative activity and lower starting temperature.

Surface modification of polymers has been investigated using low temperature plasma techniques such as plasma grafting and plasma immersion ion implantation. The polymers studied include polyethylene terephthalate tyre cord, silk fabrics, and polyimide films and the changes in molecular structure of the polymer surface were analysed with the aid of X-ray photoelectron spectroscopy and attenuated total reflection infrared spectroscopy.

To realize flexible lithium-ion batteries (LIBs), the design of flexible electrode/current collector materials with high mechanical flexibility, superior conductivity and excellent electrochemical performance and electrical stability are highly desirable. In this work, we developed a new ternary Cd2GeO4 nanowire/graphene oxide/carbon nanotube nanocomposite (Cd2GeO4 NW/GO/CNT) film electrode. Benefiting from the efficient combination of GO and Cd2GeO4 NWs, our Cd2GeO4 NW/GO/CNT composite film exhibits a capacity of 784 mA h g(-1) after 30 cycles at 200 mA g(-1), which is 2.7 times higher than that of Cd2GeO4 NW/CNT film (290 mA h g(-1)). At a higher rate of 400 mA g(-1) and 1 A g(-1), the Cd2GeO4 NW/GO/CNT film delivers a stable capacity of 617 and 397 mA h g(-1), respectively. Even at 2.5 A g(-1), it still exhibits a high rate capacity of 180 mA h g(-1). The flexible Cd2GeO4 NW/GO/CNT film clearly demonstrates good cycling stability and rate performance for anode materials in LIBs. This route may be extended to design other flexible free-standing metal germanate nanocomposite anode materials.

We previously reported 18F-labeled pyrazolo[1,5-a]pyrimidine derivatives: 7-(2-[18F]fluoroethylamino)-5-methylpyrazolo[1,5-a]pyrimidine-3-carbonitrile ([18F]1) and N-(2-(3-cyano-5-methylpyrazolo[1,5-a]pyrimidin-7-ylamino)ethyl)-2-[18F]fluoro-4-nitro- benzamide ([18F]2). Preliminary biodistribution experiments of both compounds showed s slow clearance rate from excretory tissues which warranted further investigation for tumor imaging with PET. Here we modified [18F]1 and [18F]2 by introducing polar groups such as ester, hydroxyl and carboxyl and developed three additional 18F-18 labeled pyrazolo[1,5-a] pyrimidine derivatives: (3-Cyano-7-(2-[18F]fluoroethylamino)pyrazolo[1,5-a]-pyrimidin-5- yl)methyl acetate ([18F]3), 7-(2-[18F]fluoroethylamino)-5-(hydroxymethyl)pyrazolo[1,5-a]- pyrimidine-3-carbonitrile ([18F]4) and (S)-6-(3-cyano-5-methylpyrazolo[1,5-a]pyrimidin-7- ylamino)-2-(2-[18F]fluoro-4-nitrobenzamido)hexanoic acid ([18F]5). The radiolabeled probes were synthesized by nucleophilic substitution of the corresponding tosylate and nitro precursors with 18F-fluoride. In Vitro studies showed higher uptake of [18F]3 and [18F]4 than that of [18F]5 by S180 tumor cells. In Vivo biodistribution studies in mice bearing S180 tumors showed that the uptake of both [18F]3 and [18F]4 in tumors displayed an increasing trend while the uptake of [18F]5 in tumor decreased through the course of the 120 min study. This significant difference in tumor uptake was also found between [18F]1 and [18F]2. Thus, we compared the biological behavior of the five tracers and reported the tumor uptake kinetic differences between 2-[18F]fluoroethylamino- and 2-[18F]fluoro-4-nitro- benzamidopyrazolo[1,5-a] pyrimidine derivatives.

Two novel pyrazolo[1,5-a]pyrimidine derivatives, 7-(2-[(18)F]fluoroethylamino)-5-methylpyrazolo[1,5-a]pyrimidine-3-carbonitrile ([(18)F]FEMPPC, [(18)F]1) and N-(2-(3-cyano-5-methylpyrazolo[1,5-a]pyrimidin-7-ylamino)ethyl)-2-[(18)F]fluoro-4-nitrobenzamide ([(18)F]FCMPPN, [(18)F]2), have been designed and successively labeled with (18)F by the nucleophilic substitution employing tosylate and nitryl as leaving groups, respectively. The radiochemical synthesis of both compounds was completed within 60min with final high-performance liquid chromatography purification included. The corresponding radiochemical yields (without decay correction) were approximately 35% and 30%, respectively. Meanwhile, we compared the uptake characteristics of [(18)F]1 and [(18)F]2 with those of [(18)F]FDG and L-[(18)F]FET in S180 tumor cells. Furthermore, the tumor uptake of [(18)F]1 and [(18)F]2 was assessed in mice bearing S180 tumor and compared with [(18)F]FDG and L-[(18)F]FET in the same animal model. In vitro cell uptake studies showed [(18)F]1 had higher uptake than [(18)F]FDG, [(18)F]2 and L-[(18)F]FET over the 2h period. In ex vivo biodistribution showed tumor/brain uptake ratios of [(18)F]2 were 12.35, 10.44, 8.69 and 5.13 at 15 min, 30 min, 60 min and 120 min post-injection, much higher than those of L-[(18)F]FET (2.43, 2.54, 2.93 and 2.95) and [(18)F]FDG (0.59, 0.61, 1.02 and 1.33) at the same time point. What's more, the uptake of [(18)F]1 in tumor was 1.88, 4.37, 5.51, 2.95 and 2.88 at 5 min, 15 min, 30 min, 60 min and 120 min post-injection, respectively. There was a remarkable increasing trend before 30 min. The same trend was present for L-[(18)F]FET before 30 min and [(18)F]FDG before 60 min. Additionally, the tumor/brain uptake ratios of [(18)F]1 were superior to those of [(18)F]FDG at all the selected time points, the tumor/muscle and tumor/blood uptake ratios of [(18)F]1 at 30 min were higher than those of L-[(18)F]FET at the same time point. MicroPET image of [(18)F]1 administered into S180 tumor-bearing mouse acquired at 30 min post-injection illustrated that the uptake in S180 tumor was obvious. These results suggest that compound [(18)F]1 could be a new probe for PET tumor imaging.

[emim]PF6(emim=1-ethyl-3-methylimidazolium), [emim]BF4, [emim]HSO4 and corresponding PtB ionic liquid systems were synthesized from [emim]Br, respectively. The results of infrared spectrometry, HPLC and 1HNMR show that the products are objective ionic liquids. TEM of the prepared nanometer PtB in [emim]PF6 exhibits a uniform particle size of 10 nm. The methylcyclohexane (MCH) dehydrogenation reactions were processed at the normal pressure, and in the temperature range of 240?300? with the mass ratio of methylcyclohexane to PtB ionic liquid 100:1. The results show that [emim]PF6-PtB exhibit excellent dehydrogenation performance.

Two F-18 labeled fluoroarylvaline derivatives, methyl 2-(2-[(18)F]fluoro-4-nitrobenzamido)-3-methylbutanoate ([(18)F]1, [(18)F]MFNBMB) and its corresponding acid 2-(2-[(18)F]fluoro-4-nitrobenzamido)-3-methylbutanoic acid ([(18)F]2, [(18)F]FNBMBA), have been designed and synthesized, respectively, by our team. Meanwhile, we research on their biodistributions in mice model bearing S 180 tumor. Furthermore, we also carried out the biological evaluations of 2-[(18)F]fluorodeoxyglucose ([(18)F]FDG) and O-2-[(18)F]fluoroethyl-l-tyrosine (l-[(18)F]FET) in the same model for comparison with our targeting molecules [(18)F]1 and [(18)F]2. Excitingly, the tumor/blood (T/Bl) and tumor/brain (T/Br) ratios were 2.91, 7.06 at 30 min, 3.44, 5.61 at 60 min post injection for [(18)F]1, 2.32, 13.30 for [(18)F]2 at 30 min post injection, which were obviously superior to [(18)F]FDG and l-[(18)F]FET in the same model and demonstrated that [(18)F]1 and [(18)F]2, especially [(18)F]2, were potential PET imaging agents for tumor detection.

Particle size effects on the electrochemical performance of the CuO particles toward lithium are essential. In this work, a low-cost, large-scale production but simple approach has been developed to fabricate CuO nanoparticles with an average size in ~ 130 nm through thermolysis of Cu ( OH )2 precursors. As anode materials for lithium ion batteries (LIBs), the CuO nanoparticles deliver a high reversible capacity of 540 mAh g-1 over 100 cycles at 0.5 C. It also exhibits a rate capacity of 405 mAh g-1 at 2 C. These results suggest that the facile synthetic method of producing the CuO nanoparticles can enhance cycle performance, superior to that of some different sizes of the CuO nanoparticles and many reported CuO -based anodes.

Zn 0.5 Co 0.5 O solid solution materials have been extensively studied for possible spintronic applications, however, there are only a few reports using Zn 0.5 Co 0.5 O nanostructures for energy storage. Here, we report the preparation of Zn 0.5 Co 0.5 O nanoparticles with the average particle size 10 nm and their application as anode material for rechargeable Li -ion batteries (LIBs). Electrochemical measurements demonstrate that the Zn 0.5 Co 0.5 O solid solution nanoparticles deliver a stable reversible capacity of 309 mA h g-1 up to 250 cycles at 1 C rate. These results show higher-rate capability and better cycle durability compared with those of the reported ZnO or ZnO -based anodes.

A phospholipid surfactant was used to coat carbon nanotubes (CNTs) with mesoporous silica (m-silica), in which the pore characteristics can be well controlled by varying the ratio of phospholipids and other traditional surfactants (cationic, anionic and nonionic surfactants). Based on the analysis of the interaction between phosphatidylcholines and other surfactants, the mechanism of the m-silica/CNTs formation was investigated. After calcination in an inert atmosphere, the m-silica/CNTs exhibited high specific surface areas and the pore sizes were tunable by varying the experimental parameters. Importantly, the as-prepared m-silica/CNTs were found to be an effective adsorbent for organic pollutants.

In this study, we report a facile method to synthesize core–satellite structured Au/Pdop/SiO2/Fe3O4 composite nanoparticles (NPs). Firstly, polydopamine-coated silica/magnetite nanoparticles (Pdop/SiO2/Fe3O4 composites) were synthesized by the combination of a sol–gel process and an in situ polymerization method, in which tetraethyl orthosilica (TEOS) as well as dopamine acted as the precursor for silica and polydopamine (Pdop), respectively. The Pdop/SiO2/Fe3O4 composites revealed a multilayer core–shell structure, where Pdop is the outer shell of the composite. Then, numerous ‘‘satellites’’ of gold nanoparticles were assembled on the surface of Pdop/SiO2/Fe3O4via the reduction of Au3+ by the Pdop/SiO2/Fe3O4 composite itself. In addition, the size and density of the gold nanoparticles can be easily adjusted by controlling the concentration of the HAuCl4 solution. The morphology, structure, and composition of the nanocomposites are characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectrometry (XPS), and vibrating sample magnetometry (VSM). The resulting Au/Pdop/SiO2/Fe3O4 composite NPs show not only a strong magnetic response to an externally applied magnetic field, but also a high catalytic performance on catalyzing the reduction of methylene blue (MB), at ambient temperature.

A technique named as incipient wetness impregnation–hydrothermal method, combining both incipient wetness impregnation and hydrothermal method is proposed to prepare MnO2/ordered mesoporous carbon (OMC) composite as high performance electrode material for supercapacitors. The composite delivers the specific capacitance of 157.6 F/g, which is larger than that of the OMC.

The pore structure and electrochemical performance of mesoporous carbons prepared by the ZnCl 2 chemical activation method as an electrode material for a supercapacitor were investigated in this work. It is found that the impregnation ratio exerts significant effect on the pore structure of the carbons, and mesoporous carbon can be obtained at a higher impregnation ratio. The cyclability of the supercapacitor is greatly improved after the carbon (electrode material) was treated at a higher temperature by using the "two-stage sintering" process. The "grouped linear fitting method" has been proposed to obtain the effective surface area and surface-specific capacitance of the carbons. The minimum pore size that can form an electric double layer is confirmed to be 2.0 nm for the porous carbon in 1 M Et 4 NBF 4 |propylene carbonate electrolyte. Porous carbon with an abundant mesopore is featured with good rate capability.

A simple hydrothermal route has been developed for the fabricating ZnO hierarchical micro/nanostructure with excellent reproducibility. SEM and TEM analysis show that the hierarchical rod is a single-crystal, suggesting that many single-crystal micro/nanorods are assembled into ZnO hierarchical micro/nanostructures. The morphologies of the hierarchical rods can be conveniently tailored by changing the reaction parameters. And we also found citric acid plays a crucial role in the formation process of ZnO micro/nanostructures. Room-temperature photoluminescence spectra reveals that the ZnO hierarchical micro/nanostructures have a strong emission peak at 440 nm and several weak emission peaks at 420, 471 and 541 nm, respectively.

Porous Zn1 − x Mn x O (x = 0.1, 0.2, 0.44) nanosheets were prepared by a low-cost, large-scale production and simple approach, and the applications of these nanosheets as an anode material for Li-ion batteries (LIBs) were explored. Electrochemical measurements showed that the porous Zn0.8Mn0.2O nanosheets still delivered a stable reversible capacity of 210 mA h g−1 at a current rate of 120 mA g−1 up to 300 cycles. These results suggest that the facile synthetic method of producing porous Zn0.8Mn0.2O nanostructure can realize a better cycle durability with stable reversible capacity.