Synthesis,Characterization, DNA Binding Properties,and Antioxidant Activity of Novel Copper(II) and Zinc(II) Complexes with Bis(pyrrol‐2‐yl‐methylamine) Ligands

Three novel ligands H₄Lⁿ (n = 1–3) and their copper(II) and zinc(II) complexes were prepared and characterized on the basis of elemental analyses, molar conductivity, ¹H NMR, UV/Vis, and IR spectroscopy as well as mass spectrometry. DNA binding properties of the ligands and their complexes were investigated by absorption spectroscopy, ethidium bromide displacement experiments, and viscosity measurements. The experimental results indicate that the new ligands and their complexes can bind to DNA and the binding affinities of the complexes are higher than those of the ligands. In addition, the antioxidant activity of the ligands and complexes was determined by superoxide and hydroxyl radical scavenging methods in vitro, indicating that the complexes exhibit more effective antioxidant activity than the ligands alone.     

Piezoelectric atrazine sensor based on a molecularly imprinted film of titanium dioxide

We have developed a piezoelectric sensor for the determination of atrazine. It is based on the modification of a molecularly imprinted film of TiO₂ that was placed on a quartz crystal via a surface sol?Cgel process. The resulting sensor exhibits high selectivity for atrazine, a re-usability that is better than that of other sensors, a response time of 3?min, a wider linear range (0.0005?C8?mM), and a lower detection limit (0.1???M). The analytical application of the atrazine sensor confirms the feasibility of atrazine determination.

An extension of an inequality for ratios of gamma functions

In this paper, we prove that for $x+y>0$ and $y+1>0$ the inequality $\frac{{[\Gamma (x+y+1)/\Gamma (y+1)]}^{1/x}}{{[\Gamma (x+y+2)/\Gamma (y+1)]}^{1/(x+1)}}<{\left(\frac{x+y}{x+y+1}\right)}^{1/2}$ is valid if $x>1$ and reversed if $x<1$ and that the power $\frac{1}{2}$ is the best possible, where $\Gamma \left(x\right)$ is the Euler gamma function. This extends the result of [Y. Yu, An inequality for ratios of gamma functions, J. Math. Anal. Appl. 352 (2) (2009) 967–970] and resolves an open problem posed in [B.-N. Guo, F. Qi, Inequalities and monotonicity for the ratio of gamma functions, Taiwanese J. Math. 7 (2) (2003) 239–247].     

高阶广义微扰KdV方程的弱解(英文)

By using the theory of compensated compactness,we prove that there exists a sequence {uδε} converges nearly everywhere to the solution of the initial-value problem of generalized KdV equation with high order perturbation terms,namely we prove the existence of the weak solution.     

SYNCHRONIZATION OF TWO COUPLED HINDMARSH-ROSE NEURONS BY A PACEMAKER

This paper considers the synchronization of two coupled Hindmarsh-Rose neurons by a pacemaker.Based on the stability theory of differential equations,the complete synchronization of this pacemaker neuron model is reached.Moreover,we also show that pacemaker can enhance or induce synchronization.Numerical simulations are given to illustrate the main results.     

Exact solutions of the generalized K(m, m) equations

Family of equations, which is the generalization of the K(m, m) equation, is considered. Periodic wave solutions for the family of nonlinear equations are constructed.     

Attractive singularity problems for superlinear Liénard equation

Positivity - In this paper, we consider the following quasilinear Liénard equation with a singularity $$\begin{aligned} (\phi _p(x'(t)))'+f(x(t))x'(t)+g(t,x(t))=e(t),...     

Sharp inequalities related to the functional $$U_j$$ U j and some applications

Geometriae Dedicata - Sharp inequalities of the parameterized functional $$U_j$$ for Borel measures on the unit sphere in $${\mathbb {R}}^n$$ are established. As two applications, some inequalities...     

13C chemical-shift anisotropy of alkyl-substituted aromatic carbon in anthracene derivatives

The ¹³C chemical-shift anisotropy in anthracene derivatives (9,10-dimethylanthracene, 9,10-dihydroanthracene, dianthracene, and triptycene) has been measured by the 2D FIREMAT timed pulse sequence and the corresponding set of principal values has been determined by the TIGER processing method. These molecules expand the data base of ¹³C CSA measurements of fused aromatic rings some bridged by sp³ carbon resulting in an unusual bonding configuration, which leads to distinctive aromatic ¹³C CSA values. Crystal lattice distortions to the CSA were observed to change the isotropic shift by 2.5 to 3.3 ppm and changes as large as 8.3 ppm in principal components. Modeling of the CSA data by GIPAW DFT (GGA-PBE/ultrafine) shielding calculations resulted in an rms chemical-shift distance of 2.8 ppm after lattice including geometry optimization of the diffraction structures by the GIPAW method at GGA-PBE/ultrafine level. Attention is given to the substituted aromatic carbon in the phenyl groups (here forth referred to as the α-carbon) with respect to CSA modeling with electronic methods. The ¹³C CSA of this position is accurately determined due to its spectral isolation of the isotropic shift that limits overlap in the FIREMAT spectrum. In cases where the bridging ring is sp³ carbon, the current density is reduced from extending beyond the peripheral phenyl groups; this plays a significant role in the magnetic shielding of the α-position. Nuclear independent chemical-shift calculations based on GIAO DFT (B3LYP/6-31G(d)) shielding calculations were used to model the intramolecular π-interactions in dianthracene and triptycene. These NICS results estimate the isotropic shift of the α-position in dianthracene to be insignificantly affected by the presence of the neighboring aromatic rings. However, a notable change in isotropic shielding, Δσ_iso=−2.1 ppm, is predicted for the α- position of triptycene. Experimentally, the δ₂₂ principal component at the α-position for both dianthracene and triptycene increases by at least 12 ppm compared to 9,10-dihydroanthracene. To rationalize this change, shielding calculations in idealized structures are explored. The spatial position of the bicyclic scaffolding of the bridging ring plays a key role in the large increase in δ₂₂ for the α-carbon.