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The need for clean and efficient energy storage has become the center of attention due to the eminent global energy crisis and growing ecological concerns. A key component in this effort is the ultra-high performance battery, which will play a major role in the energy industry. To meet the demands in portable electronic devices, electric vehicles, and large-scale energy storage systems, it is necessary to prepare advanced batteries with high safety, fast charge ratios, and discharge capabilities at a low cost. Cathode materials play a significant role in determining the performance of batteries. Among the possible electrode materials is vanadium pentoxide, which will be discussed in this review, due to its low cost and high theoretical capacity. Additionally, aqueous electrolytes, which are environmentally safe, provide an alternative approach compared to organic media for safe, cost-effective, and scalable energy storage. In this review, we will reveal the industrial potential of competitive methods to grow cathodes with excellent stability and enhanced electrochemical performance in aqueous media and lay the foundation for the large-scale production of electrode materials.  相似文献   
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The boron dipyrrin (Bodipy) chromophore was combined with either a free-base or a Zn porphyrin moiety (H(2)P and ZnP respectively), via an easy synthesis involving a cyanuric chloride bridging unit, yielding dyads Bodipy-H(2)P (4) and Bodipy-ZnP (5). The photophysical properties of Bodipy-H(2)P (4) and Bodipy-ZnP (5) were investigated by UV-Vis absorption and emission spectroscopy, cyclic voltammetry, and femtosecond transient absorption spectroscopy. The comparison of the absorption spectra and cyclic voltammograms of dyads Bodipy-H(2)P (4) and Bodipy-ZnP (5) with those of their model compounds Bodipy, H(2)P, and ZnP shows that the spectroscopic and electrochemical properties of the constituent chromophores are essentially retained in the dyads indicating negligible interaction between them in the ground state. In addition, luminescence and transient absorption experiments show that excitation of the Bodipy unit in Bodipy-H(2)P (4) and Bodipy-ZnP (5) into its first singlet excited state results in rapid Bodipy to porphyrin energy transfer-k(4) = 2.9 × 10(10) s(-1) and k(5) = 2.2 × 10(10) s(-1) for Bodipy-H(2)P (4) and Bodipy-ZnP (5), respectively-generating the first porphyrin-based singlet excited state. The porphyrin-based singlet excited states give rise to fluorescence or undergo intersystem crossing to the corresponding triplet excited states. The title complexes could also be used as precursors for further substitution on the third chlorine atom on the cyanuric acid moiety.  相似文献   
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Water adsorption in metal–organic frameworks has gained a lot of scientific attention recently due to the potential to be used in adsorption-based water capture. Functionalization of their organic linkers can tune water adsorption properties by increasing the hydrophilicity, thus altering the shape of the water adsorption isotherms and the overall water uptake. In this work, a large set of functional groups is screened for their interaction with water using ab initio calculations. The functional groups with the highest water affinities form two hydrogen bonds with the water molecule, acting as H-bond donor and H-bond acceptor simultaneously. Notably, the highest binding energy was calculated to be −12.7 Kcal/mol for the -OSO3H group at the RI-MP2/def2-TZVPP-level of theory, which is three times larger than the reference value. Subsequently, the effect of the functionalization strategy on the water uptake is examined on a selected set of functionalized MOF-74-III by performing Monte Carlo simulations. It was found that the specific groups can increase the hydrophilicity of the MOF and enhance the water uptake with respect to the parent MOF-74-III for relative humidity (RH) values up to 30%. The saturation water uptake exceeded 800 cm3/cm3 for all candidates, classifying them among the top performing materials for water harvesting.  相似文献   
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Nanocomposites of polystyrene-b-polyisoprene (PS-b-PI) copolymer with layered-smectite clays (organically modified montmorillonite) and nanostructured clay-carbon nanotube hybrids were prepared. The diblock copolymer was synthesized by anionic polymerization using high-vacuum techniques and was molecularly characterized by size exclusion chromatography. Carbon nanotubes were developed on clay-supported nickel nanoparticles by the CCVD method. Nanotubes attached on the clay platelets were then chemically modified to create ester groups on their surfaces. PS-b-PI nanocomposites at various polymer to reinforcement loadings were prepared by solution intercalation. The final nanocomposites were characterized by powder X-ray diffraction, FT-IR spectroscopy, thermal analysis, and scanning electron microscopy. The experiments complemented with viscometry measurements reveal the successful incorporation of the reinforcements in the polymer mass.  相似文献   
5.
Royal jelly, one of the most important bee products, can be contaminated with pesticide and/or antibiotic residues resulting from treatments applied either inside beehives or in the agricultural environment. A new multiresidue method was developed and validated for analysis of nine pesticides in royal jelly. Solid-phase extraction RP-C(18) cartridges were used for sample purification and isolation of analytes. Final solution was analyzed with GC and micro-electron-capture detection. Four synthetic acaricides used by beekeepers (bromopropylate, coumaphos, malathion and tau-fluvalinate), and moreover one pyrethroid, two organochlorine, and two organophosphate insecticides were tested. Linearity is demonstrated for the range of 0.0025-1mgkg(-1), with correlation coefficients ranging from 0.99991 to 0.99846, depending on the analyte. Overall recovery rates from royal jelly blank samples spiked at five fortification levels ranged from 80.8% (lindane) to 91.3% (ethion), well above the range defined by the SANCO/10232/2006 and EC/675/2002 documents. The limit of quantification was <0.003-0.005 mg kg(-1) depending on the analyte, and the reporting level of the method, defined as the lowest recovery level, was 0.005 mg kg(-1).  相似文献   
6.
The interaction of carbon dioxide with a series of functionalized aromatic molecules was studied by using quantum mechanical methods (MP2), to examine the effect of the substituent on the adsorption of CO2. Several different initial configurations of CO2 were taken into account for each functionalized benzene to locate the energetically most favorable configuration. To get a better estimation of the binding energies, we applied an extrapolation scheme to approach the complete basis set. CH2N3‐, COOH‐, and SO3H‐functionalized benzenes were found to have the strongest interaction with CO2, and the corresponding binding energies were calculated to be ?3.62, ?3.65, and ?4.3 kcal mol?1, respectively. Electrostatic potential maps of the functionalized benzenes and electron redistribution density plots of the complexes were also created to get a better insight into the nature of the interaction of CO2 with the functionalized benzenes. The functional groups that were examined can be potentially incorporated in organic bridging molecules that connect the inorganic corners in MOF.  相似文献   
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