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991.
A novel kind of inorganic-organic hybrid supramolecular hydrogel with excellent anti-biofouling capability was developed. The hydrogel was formed via ionic interaction between the negative-charged sodium polyacrylate (SPA) entwined clay nanosheets (CNS) and positive-charged polyhedral oligomeric silsesquioxane (POSS) core-based generation one (L-Arginine) dendrimer (POSS-R).  相似文献   
992.
Carrier diffusion and recombination kinetics in all-inorganic CsPbI3 perovskite microcrystals directly synthesized in solution phase are reported.  相似文献   
993.
Fluorescent nano-probes with particle sizes of 20 nm, 120 nm and 300 nm for proton were prepared through click reaction. The photophysical properties of the nano-probes were mainly affected by the particle size.  相似文献   
994.
Lithium–sulfur (Li–S) battery is considered as a promising option for electrochemical energy storage applications because of its low-cost and high theoretical capacity. However, the practical application of Li–S battery is still hindered due to the poor electrical conductivity of S cathode and the high dissolution/shuttling of polysulfides in electrolyte. Herein, we report a novel physical and chemical entrapment strategy to address these two problems by designing a sulfur–MnO2@graphene (S–MnO2@GN) ternary hybrid material structure. The MnO2 particles with size of ~ 10 nm are anchored tightly on the wrinkled and twisted GN sheets to form a highly efficient sulfur host. Benefiting from the synergistic effects of GN and MnO2 in both improving the electronic conductivity and hindering polysulfides by physical and chemical adsorptions, this unique S–MnO2@GN composite exhibits excellent electrochemical performances. Reversible specific capacities of 1416, 1114, and 421 mA h g?1 are achieved at rates of 0.1, 0.2, and 3.2 C, respectively. After a 100 cycle stability test, S–MnO2@GN composite cathode could still maintain a reversible capacity of 825 mA h g?1.  相似文献   
995.
The effects of the types and contents of surfactants, alkali types and concentrations, oil-water ratios, mixing speeds, and emulsifying temperatures on the rheology of heavy oil-in-water (O/W) emulsions were studied. The experimental results showed that the apparent viscosity increased as the formulated surfactant content increased. The organic/inorganic alkali played a twofold role in the apparent viscosity of the O/W emulsion, promoting the ionization of these interfacial active components and compressing the diffused double layer, the competition of which determined whether the apparent viscosity increased or decreased. With increasing oil-water ratios, the apparent viscosity increased, whereas an increase in the emulsifying temperature resulted in a decrease of the apparent viscosity. When the mixing speed was increased from 500 to 1000?r/min, the apparent viscosity increased. However, the apparent viscosity changed minimally for mixing speeds in the range of 1000–1500?r/min. To further discuss the impacts of these factors on the emulsion rheology and pressure drop, the results of an orthogonal test were analyzed through ANOVA using SPSS software; the pressure drops in the samples were calculated using Matlab software. The results demonstrated that the effects of the oil-water ratios on emulsion viscosity and pressure drop were the most prominent.  相似文献   
996.
A three‐dimensional (3D) cage‐like organic network (3D‐CON) structure synthesized by the straightforward condensation of building blocks designed with gas adsorption properties is presented. The 3D‐CON can be prepared using an easy but powerful route, which is essential for commercial scale‐up. The resulting fused aromatic 3D‐CON exhibited a high Brunauer–Emmett–Teller (BET) specific surface area of up to 2247 m2 g?1. More importantly, the 3D‐CON displayed outstanding low pressure hydrogen (H2, 2.64 wt %, 1.0 bar and 77 K), methane (CH4, 2.4 wt %, 1.0 bar and 273 K), and carbon dioxide (CO2, 26.7 wt %, 1.0 bar and 273 K) uptake with a high isosteric heat of adsorption (H2, 8.10 kJ mol?1; CH4, 18.72 kJ mol?1; CO2, 31.87 kJ mol?1). These values are among the best reported for organic networks with high thermal stability (ca. 600 °C).  相似文献   
997.
Methods for the hydrogenation of CO2 into valuable chemicals are in great demand but their development is still challenging. Herein, we report the selective hydrogenation of CO2 into ethanol over non‐noble cobalt catalysts (CoAlOx), presenting a significant advance for the conversion of CO2 into ethanol as the major product. By adjusting the composition of the catalysts through the use of different prereduction temperatures, the efficiency of CO2 to ethanol hydrogenation was optimized; the catalyst reduced at 600 ° gave an ethanol selectivity of 92.1 % at 140 °C with an ethanol time yield of 0.444 mmol g?1 h?1. Operando FT‐IR spectroscopy revealed that the high ethanol selectivity over the CoAlOx catalyst might be due to the formation of acetate from formate by insertion of *CHx, a key intermediate in the production of ethanol by CO2 hydrogenation.  相似文献   
998.
We used nearest‐neighbor searches in chemical space to improve the activity of the antimicrobial peptide dendrimer (AMPD) G3KL and identified dendrimer T7 , which has an expanded activity range against Gram‐negative pathogenic bacteria including Klebsiellae pneumoniae, increased serum stability, and promising activity in an in vivo infection model against a multidrug‐resistant strain of Acinetobacter baumannii. Imaging, spectroscopic studies, and a structural model from molecular dynamics simulations suggest that T7 acts through membrane disruption. These experiments provide the first example of using virtual screening in the field of dendrimers and show that dendrimer size does not limit the activity of AMPDs.  相似文献   
999.
Although many assembly strategies have been used to successfully construct well‐aligned nanowire (NW) assemblies, the understanding of their assembly kinetics has remained elusive, which restricts the development of NW‐based device and circuit fabrication. Now a versatile strategy that combines interfacial assembly and synchrotron‐based grazing‐incidence small‐angle X‐ray scattering (GISAXS) is presented to track the assembly evolution of the NWs in real time. During the interface assembly process, the randomly dispersed NWs gradually aggregate to form small ordered NW‐blocks and finally are constructed into well‐defined NW monolayer driven by the conformation entropy. The NW assembly mechanism can be well revealed by the thermodynamic analysis and large‐scale molecular dynamics theoretical evaluation. These findings point to new opportunities for understanding NW assembly kinetics and manipulating NW assembled structures by bottom‐up strategy.  相似文献   
1000.
建立了一种用稀盐酸溶解样品,标准工作溶液中匹配钾,ICP-AES测定高铼酸钾中19种杂质元素的方法。在选定的仪器工作条件下,样品加标回收率(%)分别为:钠94.4~101、钙98.8~102、铝98.1~102、镁95.8~99.1、钴98.4~101、钼97.3~103、钛97.6~102、钒96.6~106、锆96.2~97.7、铬97.8~101、铜98.1~108、铁92.9~104、锰95.5~98.4、镍93.6~101、钯93.3~101、铅96.5~103、锌95.2~103、铂95.9~99.9、铑94.5~96.3;方法精密度RSD%(n=7)分别为:钠2.0~5.5、镁1.1~3.5、铝0.9~2.5、钙1.5~7.3、钴1.1~3.1、钼0.9~4.5、钛1.0~2.8、钒1.6~4.0、锆1.4~3.6、铬0.77~4.6、铜0.74~1.8、铁1.3~3.8、锰1.1~2.0、镍0.99~5.0、钯1.1~2.4、铅1.3~9.1、锌0.80~6.7、铂1.2~10、铑0.78~8.6。方法简便、快速、准确, 满足生产分析要求。  相似文献   
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