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A. Martinez A. Queijeiro D. M. Tun 《Zeitschrift fur Physik C Particles and Fields》1995,66(4):607-611
We study the production process
, where
is a proton (antiproton), allowing an anomalous weak magnetic dipole moment parameter
Z
in the ZWW vertex. We compute the pairWZ mass invariant, and total cross section production for various values of
Z
. 相似文献
3.
4.
Tanja Vidaković-Koch Tamara Miličić Luka A. Živković Hoon Seng Chan Ulrike Krewer Menka Petkovska 《Current Opinion in Electrochemistry》2021
The nonlinear frequency response analysis (NFRA) can be seen as an extension of electrochemical impedance spectroscopy. NFRA gives a full and detailed representation of the system response and can establish a connection between model parameters and the experimentally observed phenomena. In this article, different theoretical NFRA approaches and the most recent application examples are discussed. A simple electrochemical example is used to showcase the benefits and disadvantages of analyzing the system response by using different approaches. In addition, it was shown how to extract experimental harmonic values and analyze them. 相似文献
5.
Base hydrolysis of bis-bipyridylplatinum(II) occurs via a 1:1 intermediate adduct with hydroxide ion. The equilibrium constants for this 1:1 addition of hydroxide inwater to complex ions [PtL2]2+, where L=one of theisoelectronic set 2,2-bipyridyl (bpy); 2,2- bipyrazine (bpz); 3,3-bipyridazine (bpdz) and 2,2- bipyrimidine (bpym) are respectively (as log10K at 25°C): 4.23; 4.59; 3.82; 6.14. This result is rationalized in terms of addition at the 6–position of the ligand. 相似文献
6.
Abubakar Lawal Richard Chee Seng Wong Guan Huat Tan Lukman Bola Abdulra’uf Ali Mohamed Ali Alsharif 《Chromatographia》2018,81(5):759-768
Pesticides play vital roles in agricultural practices, but the nature and mishandling of the chemicals have led to their accumulation in moist soil, vegetables and fruits. Thus, development of efficient methods for pesticides determination is one of the most important ways to address such challenges. Multivariate response surface methodology optimisation using Placket–Burman and Box–Behnken designs were respectively used for screening and optimisation of significant factors of quick, easy, cheap, effective, rugged and safe (QuEChERS) with dispersive solid-phase extraction (SPE). Consequently, the optimised QuEChERS-dSPE technique coupled with modified ionic liquid-based (IL-based) dispersive liquid–liquid microextraction was used for sample preparation before LC–MS/MS. The developed method was validated (SANTE 11831-2017) for multi-pesticide residues determination in samples of bananas, cabbages, tomatoes, oranges and onions. The precision results were satisfactory in terms of relative standard deviation (≤?20%) as recommended. The results of accuracy for relative recoveries (82–137%) were satisfactory because 92.5% of results were within the recommended range (70–120%). The matrix effects in all the samples were very weak (less effective) (≤???80%). The linearity of the evaluated results was 5–400 µg kg?1 and regression coefficients (R2) were?>?0.99. The resulting limits of detection and quantitation were 0.02–0.32 and 0.07–1.06 µg kg?1, respectively, and therefore satisfactory. Certifiably, the estimated measurement uncertainties range (1–16%) was acceptable (≤?50%). Thus, the developed method could be reliable and suitable for routine determination of multiple pesticide residues in various vegetable and fruit samples. 相似文献
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Qianqian Liu Xiaoyu Yang Meng Wang Die Liu Mingzhao Chen Tun Wu Zhiyuan Jiang Pingshan Wang 《Tetrahedron》2019,75(16):2400-2405
A novel family of metallocycles was constructed by a one-pot self-assembly of three analogous bis(terpyridine) ligand monomers L1-L3, having different bent angles, with metal ions (Zn2+ or Cd2+). The dibenzo[b,d]thiophene-containing ligand L3 assembled with the metal ions to form a single trimer, whereas the dibenzo[b,d]furan-containing ligand L2 and dibenzo[b,d]carbazole-containing ligand L1 formed a mixture of trimers and tetramers. Heteroatoms (N, O, S) significantly contributed to the molecular size of the assemblies, owing to the bent angle of the bis-terpyridines ligands. 相似文献
9.
Loon‐Seng Tan Sharon R. Simko Shih Jung Bai Richard A. Vaia Barney E. Taylor Marlene D. Houtz Max D. Alexander Robert J. Spry 《Journal of Polymer Science.Polymer Physics》2001,39(20):2539-2548
As an alternative method for processing polyaniline (PANI) from its conducting (protonated) state, vacuum casting of PANI from a methanesulfonic acid (MSA) solution provided films with electrical conductivity values of about 130–150 S/cm. In addition, we similarly prepared blended films of PANI · MSA and poly(p‐phenylene benzobisthiazole) (PBZT). This process eliminated the need for a subsequent protonation step and had the additional advantage that the conjugated PBZT may provide alternative conducting pathways. Conductivity values of the composite films ranged from 100 pS/cm to 124 S/cm, and the films displayed critical concentration behavior with a PANI threshold concentration of 2.75% and a critical exponent of 4. Transmission electron micrographs displayed phase‐separated regions with PANI forming a continuous network at high concentrations. Thermogravimetric analysis results demonstrated the thermal and thermooxidative stability advantage of the blends due to the PBZT component. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2539–2548, 2001 相似文献
10.
The viscosities of seven n-alkylamines from n-butylamine to n-decylamine were determined from 15 to 80°C at 5°C intervals. The intrinsic volumes were determined by extrapolation of the plot of fluidity against molar volume to zero fluidity and found to be a linear function of the number of carbon atoms. Plots of the logarithm of viscosity vs. reciprocal absolute temperature were almost linear. The energies of activation for viscous flow for the n-alkylamines were calculated and found to increase with increase in the carbon number. The B values, based on Hildebrand's equation and representing a measure of a molecules resistance to transport of momentum, were calculated for each of the n-alkylamines. A modified form of the equation describing the change fluidity with temperature was then formulated. It is suggested that the activation energy for viscous flow consists of the sum of the energy required for the expansion of the void volume and the energy required to overcome intermolecular interactions. These energies were calculated and discussed. 相似文献