查看更多>>摘要：Crown ether is used widely in lithium isotope separation. Here a new system for the electromigration separation of lithium isotopes was established. By comparing the experimental results with and without crown ether, it was found that there are multiple roles for crown ether: phase transfer, selective chelation, dehydration and retention during electromigration. Though crown ether is conducive to the lithium ions migration from the anode solution into the organic solution and enrichment of Li-6 at the interface, unfavourable to the migration of lithium ions in organic solution, resulting in the weak migration efficiency and enrichment effect in organic solution.
查看更多>>摘要：The study of surfaces, which provides unique information on chemical and physical properties, has led to the development of specialized tools including Sum Frequency Generation (SFG) spectroscopy. To map the chemical heterogeneity across the surface plane, the SFG spectroscopic imaging has been developed. SFG imaging has proven to be a useful tool for studying surface specific species through their vibrational signatures. However, the effective resolution of the imaging is limited to micrometer length scales often by the diffraction limit of the midIR wavelengths deployed in vibrationally sensitive SFG imaging. Therefore, many interesting sub-micron features are out of reach for such imaging techniques. This article introduces a technique to achieve super-resolution using ground state depletion from a structured area around the focal-spot of a raster-scan imaging scheme. The proof-of-concept results are presented using hydrogen terminated silicon (Si(1 1 1)) as sample surface with results indicating a 3-fold resolution improvement.
查看更多>>摘要：We report on the green synthesis of an effective fluorescent based sensor for selective, sensitive and rapid detection of Fe3+ ions using bovine serum albumin (BSA) stabilized copper nanoclusters. The fluorescence intensity of the BSA-CuNCs has been found to be quenched with the addition of Fe3+ ions. An extremely high selectivity and low detection limit of 10 nM (3 sigma/k) was observed. The sensor was also employed for the sensing of Fe3+ in wastewater and human blood serum samples. The features exhibited by the fluorescent probe suggest its promising applications in the area of analytical and biological field.
查看更多>>摘要：In this work, we report the effects of different H2O2 concentrations on the growth velocity of ZnO thin films deposited by SILAR method.H2O2 effects on the films' growth velocity were studied by Rutherford Backscattering Spectroscopy (RBS) technique. RBS results showed that thickness can be increased from 0 up to 290 +/- 20 [nm] by increasing the H2O2 concentration from 0 to 30 %, evidencing the strong catalyzer effect of H2O2 on the films' growth velocity. Our study provides relevant insights on the use of H(2)O(2 )as a key parameter for tuning the thickness of SILAR-deposited ZnO thin films.
查看更多>>摘要：NEGF and DFT calculations within Fisher Lee formalism are used to explore the effect of the asymmetry and the strength of coupling with the electrode on transport properties of (1-(2-bisthienyl)benzene) oligomers. Electronic analysis of metal-molecule interactions reveals the ionic nature of Ti-C bonds inducing an interfacial dipole. The Ti d -orbitals are found to be strongly coupled to the lowest unoccupied orbital of BTB, thus facilitating charge transfer from Ti to the molecule. The hole transport mechanism is found in the cases of Au-(BTB)(n)-Au and Au(BTB)(n)-Ti while possible combined hole and electron transport is predicted in the case of Ti-(BTB)(n)-Ti.
Sruthi, P.Swapna, K.Kumar, J. V. ShanmukhMahamuda, Sk....
9页
查看更多>>摘要：Different concentrations of dysprosium (Dy3+) ions doped antimony lead oxufluoroborate (SbPbOFB) glasses were synthesized through melt quenching method. These prepared glasses are aimed to study for their utility in photonic device applications such as white Light Emitting Diodes (w-LEDs) and visible lasers. Glassy nature and thermal stability of the undoped SbPbOFB glass was investigated by X-Ray Diffraction (XRD) and Thermal Gravimetry Analysis (TGA) techniques. Spectroscopic features were studied by diverse methods like optical absorption, photoluminescence (PL) excitation, PL emission and PL decay spectra. The Judd-Ofelt (J-O) analysis was used to understand the asymmetry and bonding nature in the as prepared glasses. The emission spectra recorded from 400 to 700 nm show three intense bands in blue (482 nm), yellow (575 nm) and red (663 nm) regions corresponds to the transitions F-4(9/2)& nbsp; -> H-6(15/2), F-4(9/2) -> H-6(13/2) and F-4(9/2) -> 6H(11/2) respectively. Relatively higher values of emission cross-section (sigma(se)) along with branching ratio and quantum efficiency obtained for SbPbOFBDy1.0 glass for F-4(9/2) -> (9/2) transition (yellow band) reveal its ability as potential candidate for visible yellow lasers. The Commission Internationale de I'Elcairage (CIE) color chromaticity coordinates estimated from the PL spectra are in proximity with the traditional white light coordinates (x = 0.333, y = 0.333) and illustrate the ability of the as prepared glasses to fabricate w-LEDs.
查看更多>>摘要：In this presentation, Bi2S3/BiOCl nanoparticles with excellent photocatalytic capacity were in-situ construct by a hydrothermal approach using 3-mercaptopropionic (3 M) acid. 3 M acid can provide S source for Bi2S3 and modify BiOCl at the same time. In-situ construction of Bi2S3/BiOCl composites can induce BiOCl to form thin sheets, facilitating the segregation of photoactivated carriers. Under the irradiation of a 500 W Xe lamp, Bi2S3/BiOCl has better catalytic capability than BiOCl for removal of Rhodamine B (RhB) and Cr (VI). The catalytic capability of Bi2S3/BiOCl is 2.5 and 2.9 times of that of BiOCl toward abatement of RhB and Cr (VI), respectively.
查看更多>>摘要：In this paper, spherical g-C3N4 modified by N defect and O doping was prepared by a simple hydrothermal method, and combined with CdS to form a direct Z-type heterojunction. Combined with a series of characterizations (XRD, SEM, BET, FTIR and UV-vis DRS), the results show that the addition of CTAB brings a lot of positive charges on the surface of N-OCN. According to the principle of electrostatic attraction, positively charged N-OCN negatively charged CdS attract each other, which strengthens the close contact between CdS and N-OCN and plays an important role in stabilizing the formation of heterojunction. CdS is anchored to N-OCN through electrostatic interaction. Under the irradiation of visible light, the electrons on CB on positively charged N-OCN combine with holes on negatively charged CdS valence band, which improves the redox ability in photocatalytic reaction system. Taking methyl orange (MO) as a pollutant degradation model, the possible degradation mechanism was discussed in detail. This study provides a simple, effective and wide application method for the modification of g-C3N4.
查看更多>>摘要：The interaction of molybdenum disulfide (MoS2) with water and consequently the surface wettability are important to understand to efficiently use this layered material in semiconductor and lubricant applications. Using molecular dynamics simulations, we investigate the coupled effect of flake orientation (0 degrees and 90 degrees) and temperatures (300 K and 400 K) on the wettability of MoS2. Our results reveal that the horizontally oriented MoS2 is relatively less hydrophilic than the vertically oriented MoS2 due to the difference in the flake-orientation driven atomic interactions. An increase in temperature (>= 400 K) transforms the horizontally oriented MoS2 to a relatively hydrophobic surface, while retaining the hydrophilicity in the vertically oriented flakes due to the bond anisotropy in the material, which impacts the surface free energy.
查看更多>>摘要：To better understand the fate of dichlorodiphenyltrichloroethane (DDT) in the atmosphere, probing the oxidation mechanism of DDT is of great importance. The results showed that the degradation of DDT yields oxygenated DDT and nitrated DDT including phenolic compounds, dialdehyde, epoxides and nitrooxy-DDT. The rate constant for the reactions of DDT with OH and NO3 radicals are 1.16 x 10(-11) cm(3) molecule(-1) s(-1) and 2.19 x 10(-14) cm(3) molecule(-1) s(-1), respectively in the temperature of 298 K. The lifetime of DDT determined by the reactions with OH and NO3 radicals is 8.1 h.
NSTL
Elsevier