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991.
Dihydromyricetin     
A study on the efficiency of bio-based compound as stabilizer for linear low density polyethylene (LLDPE) is reported. A water extract from Ampelopsis grossedentata (Dihydromyricetin) is used. Its stabilizing activity is compared with two commercial phenolic antioxidants: methyl gallate (MG) and Irganox 1010. Based on the measurement of the oxidation onset temperature (OOT) of LLDPE/antioxidant samples, it is found that the antioxidant ability of the three kinds of antioxidants is in the following order: DMY > 1010 > MG. The antioxidant ability and thermal decomposition activation energy (E a) of antioxidants are further examined by thermal gravimetric analysis. The effects of water extraction on the migration resistance of LLDPE/antioxidants are also evaluated by monitoring the OOT change, demonstrating that DMY retained high stability against migration.  相似文献   
992.
The article presents the effect of attapulgite (ATT) and its synergic action with carbon or silica on the thermal properties and flammability of cross-linked styrene–butadiene rubber. It has been shown that ATT is active filler improving the thermal and mechanical properties of composites containing this aluminosilicate. The decreased flammability of vulcanizates containing ATT compared to that of unfilled vulcanizates results from good insulating properties of the ATT used. The considerable reduction in the flammability of composites containing ATT and carbon nanofiber or silica is connected, first of all, with the formation of a homogeneous boundary layer.  相似文献   
993.
The solidification/melting of cetane confined in nine silica glasses with specific controlled pores (CPG) with different pore sizes (r p ranging from 3.7–72 nm) has been studied. Samples with variable coefficient of filling of cetane were prepared and analyzed. Combining the indication of the evolving solidification heats (via differential scanning calorimetry, DSC) with the lifetime spectra of positron annihilation, the mechanism of filling of cetane molecules in the pores of the hosting silica glass matrices has been searched. Three independent solidification effects—three independent DSC peaks—were observed in each measuring cycle, namely one crystallization exotherm Rb of the bulk-cetane (if present) and two crystallization sub-peaks Rc1 and Rc2 of the confined cetane in the case of continuous cooling. The temperatures of both Rc1 and Rc2 effects decrease on decreasing the r p of the CPG matrix. The mutual relation between Rc1 and Rc2 has been analyzed. The kinetics of all three steps of the solidification in the continuous-cooling as well as isothermal regimes have been specified.  相似文献   
994.
Li2FeSiO4/C cathode materials have been prepared using the conventional solid-state method by varying the sintering temperature (650 °C, 700 °C and 750 °C), and the structure and electrochemical performance of Li2FeSiO4/C materials are investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), galvanostatic charge–discharge tests, respectively. The results show that Li2FeSiO4 nano-crystals with a diameter of about 6–8 nm are inbedded in the amorphous carbon, and the Li2FeSiO4/C material obtained at 700 °C exhibits an initial discharge capacity of 195 mA?h g?1 at 1/16 C in the potential range of 1.5–4.8 V. The excellent electrochemical performance of Li2FeSiO4/C attributes to the improvement of conductivity and reduction of impurity by the optimization of the sintering temperature.  相似文献   
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999.
A novel fluorescent nanoprobe for glutathione S‐transferase (GST) has been developed by incorporating 3,4‐dinitrobenzamide (a specific substrate of GST) onto CdTe/ZnTe quantum dots. The probe itself displays a low background signal due to the strong quenching effect of the electron‐withdrawing unit of 3,4‐dinitrobenzamide on the quantum dots. However, GST can efficiently catalyze the nucleophilic substitution of reduced glutathione on the p‐nitro group of the nanoprobe, leading to a large fluorescence enhancement. Most notably, this enhancement shows high selectivity and sensitivity towards GST instead of the other biological substances. With this nanoprobe, a simple fluorescence imaging method for intracellular GST has been established, and its applicability has been successfully demonstrated for imaging GST in different living cells, which reveals that A549 cells express GST about 3 times higher than NIH‐3T3 and Hela cells.  相似文献   
1000.
The extractive desulfurization of dibenzothiophene(DBT),benzothiophene(BT),and 4,6-dimethyldi-benzothiophene (4,6-DMDBT) in model oil was carried out using anhydrous FeCl3 and 1-methyl-3-octylimidazolium chloride system([Omim|Cl·2FeCl3).This new system exhibited high extractive efficiency and the sulfur removal of DBT in model oil(VIL/Voil=1/20) could reach 99.4%at room temperature for 30 min,which was obviously superior to single[Omim]Cl as extractant(22.9%).When the[Omim|CI·2FeCl3 was used,the S-removal of 4,6-DMDBT and BT could also be up to 99.3%and 96.2%, respectively.Moreover,the ionic liquid could be recycled five times without a significant decrease in extractive ability.  相似文献   
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