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Selective semi-hydrogenation of phenylacetylene to styrene is a crucial step in the polystyrene industry. Although Pd-based catalysts are widely used in this reaction due to their excellent hydrogenation activity, the selectivity for styrene remains a great challenge. Herein, we designed a mesoporous silica stabilized Pd-Ru@ZIF-8 (MS Pd-Ru@ZIF-8) nanoreactor with novel Pd and Ru single site synergistic catalytical system for semi-hydrogenation of phenylacetylene. The nanoreactor exhibited a superior performance, achieving 98% conversion of phenylacetylene and 96% selectivity to styrene. Turnover frequency (TOF) of nanoreactor was up to as high as 2,188 h⁻¹, which was 25 times and 5 times more than the single metal species catalysts, mesoporous silica stabilized Pd@ZIF-8 nanoreactor (MS Pd@ZIF-8), and mesoporous silica stabilized Ru@ZIF-8 nanoreactor (MS Ru@ZIF-8). This catalytic activity was attributed to the synergistic effect of Pd and Ru single site anchored strongly into the framework of ZIF-8, which reduced the desorption energy of styrene and increased the hydrogenation energy barrier of styrene. Importantly, since the ordered mesoporous silica was introduced into the nanoreactor shell to stabilize ZIF-8, MS Pd-Ru@ZIF-8 showed excellent reusability and stability. After the five cycles, the catalytical activity and selectivity still remained. This work provides insights for a synergistic catalytic system based on single-site active sites for selective hydrogenation reactions.

The β-barrel structure of green fluorescent protein (GFP) provides a confined environment to enhance its fluorescence efficiency. Inspired by the unique structure of GFP, we reported a self-restricted GFP chromophore analogue which was rationally grafted onto the middle or the terminal of poly(ethylene glycol)-block-poly(N-isopropyl acrylamide) (PEG-b-PNIPAM) via click chemistry to obtain PEG-GA-PNIPAM and PEG-PNIPAM-GA (GA: MeOBDPI). These structures were characterized through NMR, GPC, and FT-IR. By varying the length of PNIPAM and the location of the GFP chromophore, self-assembly behaviour and fluorescence intensity were correspondingly changed. PEG-GA-PNIPAM and PEG-PNIPAM-GA were assembled into nano-sized spherical micelles above the low critical solution temperature (LCST). The size of the micelles increased with the length of the PNIPAM block. These optical properties were carefully evaluated by UV-Vis and fluorescence spectroscopy. The results indicated that increasing the length of the PNIPAM block enhanced the fluorescence in water, and PEG-PNIPAM74-GA has more remarkable fluorescence intensity than PEG-GA-PNIPAM106 in living cells such as MCF-7 cells. Furthermore, the fluorescence behaviour of PEG-PNIPAM74-GA was studied in MCF-7 cells and L929 cells. The result showed that PEG-PNIPAM74-GA was mostly located in the cytoplasm. Compared with the CellTracker™ Red CMTPX dye, it could enter into MCF-7 cells and L929 cells more easily in DMEM with 10% FBS. Therefore, PEG-PNIPAM74-GA has potential application prospects for living cell imaging.

Polypyrrole (PPy)-modified CuO nanocomposites (NCs) with various shell structures have been synthesized by controlling the polymerization time of pyrrole in the presence of leaf-like CuO nanobelts (NBs) as wire templates. The synthesized CuO/PPy NCs and CuO NBs are characterized by XRD, FT–IR, TGA, SEM, TEM, STEM, and EDX line analysis/elemental mapping. The formation mechanism of CuO/PPy core–shell NCs is also illustrated. Electrochemical lithium-storage properties of all the products are evaluated by using them as anode materials for Li-ion batteries (LIBs). It is found that the polymerization time of pyrrole plays a significant role in affecting the shell structures and subsequent lithium-storage properties of the hybrid CuO/PPy NCs. With the extension of polymerization time, CuO/PPy NCs gradually form typical core–shell structures, where the doped PPy with increasing content is steadily and uniformly coated on the CuO surface. Correspondingly, the discharge/charge capacity and cyclic durability of CuO...

We report on the synthesis and characterization of a series of donor–acceptor copolymers (PF1, PF2, PF3 or PF4) based on a dinaphtho-s-indacene (DNI) donor unit and four different acceptor units. The molecular weights of the copolymers were determined by using gel permeation chromatography, and their electrochemical properties were investigated by cyclic voltammetry. All four copolymers showed deep-lying highest occupied molecular orbital energy levels. Inverted bulk heterojunction solar cells were fabricated by using the synthesized copolymers as the electron donor material and 6,6-phenyl-C71-butyric acid methyl ester (PC71BM) as the electron acceptor material. Inverted solar cells based on PF1:PC71BM (1:4, w/w) exhibited a power conversion efficiency (PCE) of 3.07%, a high open-circuit voltage (Voc) of 0.99 V, a short-circuit current density (Jsc) of 7.85 mA/cm2, and a fill factor of 39.5% under the AM1.5G illumination. With the same fabrication method, the inverted devices based on PF2, PF3 and PF4 showed PCEs of 2.62, 1.18 and 1.32%, and Voc values of 0.97, 0.91 and 0.80 V, respectively.

OBJECTIVE To assess the efficacy and safety of compound matrine injection combined with cisplatin chemotherapy for advanced gastric cancer. METHOD It was searched relevant randomized Controlled trials (RCTs) from Cochrane Library, PubMed, EMBASE, CBM, and CNKI etc. The search was finished in February 11, 2010. And it was traced the related references and experts in this field, besides it was also communicated with other authors in order to obtain some certain information that had not been found. RCTs of compound matrine injection combined with cisplatin chemotherapy versus cisplatin chemotherapy for advanced gastric cancer were included. It was evaluated the quality of these included studies and analyzed data by Cochrane Collaboration's RevMan 5.0 software. RESULT Ten RCTs were included meta analysis results suggested that compared with chemotherapy alone, the combination had a statistically significant benefit in healing efficacy (OR = 1.99, 95% CI: 1.26-3.13, P < 0.05) and improving quality of life (OR = 3.83, 95% CI: 2.38-6.15, P < 0.001). Besides, the combination also had a statistically significant benefit in myelosuppression, white blood cell (OR = 0.44, 95% CI: 0.32-0.62, P < 0.001), hematoblast (OR = 0.40, 95% CI: 0.26-0.60, P < 0.001), liver function (OR = 0.33, 95% CI: 0.15-0.75, P < 0.05) and in reducing the gastroenteric reaction (OR = 0.32, 95% CI: 0.16-0.63, P = 0.001), decreasing the of CD3 ( MD = 2.96, 95% CI: 1.724. 20, P < 0.001), CD4 (MD = 9.04, 95% CI: 7.87-10.20, P < 0.001), CD4/CD8 (MD = 0.47, 95% CI: 0.41-0.54, P < 0.001) and NK cells (MD = 5.90, 95% CI: 4.53-7.26, P < 0.001). CONCLUSION Compared with cisplatin chemotherapy, compound matrine injection combined with cisplatin chemotherapy can significantly improve the efficiency, QOL and myelosuppression, and reduce adverse events.

A metal-oxide-oxide-metal (MO-OM) junction was fabricated based on anodized Al and Ta granular metal-oxide tunnel junctions. Electrical transport properties of the MO-OM junction were investigated at various temperatures. A strong asymmetric nonlinear current-voltage curve at room temperature indicated a diode-like behavior with a threshold voltage of 0.19 V under forward bias. The nonlinear current-voltage curves under forward and reverse biases were well fitted separately by the Simmons equation (J. G. Simmons, J. Appl. Phys. 34, 1793 (1963)) with barrier thickness, height, and tunneling area treated as variables.

Electron transport mechanisms in lateral tantalum granular oxide-metal tunnel junctions have been investigated at low temperatures that range from 30 to 300 K. Fowler–Nordheim tunneling was determined to be the dominant temperature-independent conducting mechanism at high field, while direct tunneling appeared in the low field regime. All the nonlinear current-voltage curves were well fitted by Simmons’ equation with barrier thickness, height, and tunneling area treated as variables. The temperature-dependent current transport can be described by variable range hopping and Coulomb blockade.