Electronic quantum motions in hydrogen molecule ion

The hydrogen molecule ion is a two‐center force system expressed under the prolate spheroidal coordinates, whose quantum motions and quantum trajectories have never been addressed in the literature before. The momentum operators in this coordinate system are derived for the first time from the Hamilton equations of motion and used to construct the Hamiltonian operator. The resulting Hamiltonian comprises a kinetic energy T and a total potential V_Total consisting of the Coulomb potential and a quantum potential. It is shown that the participation of the quantum potential and the accompanied quantum forces in the force interaction within H₂⁺ is essential to develop an electronic motion consistent with the prediction of the probability density function |Ψ|². The motion of the electron in H₂⁺ can be either described by the Hamilton equations derived from the Hamiltonian H = T_K + V_Total or by the Lagrange equations derived from the Lagrangian H = T_K ? V_Total. Solving the equations of motion with different initial positions, we show that the solutions yield an assembly of electronic quantum trajectories whose distribution and concentration reconstruct the σ and π molecular orbitals in H₂⁺. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

Novel alginate-poly(L-histidine) microcapsules as drug carriers: in vitro protein release and short term stability

Spherical, smooth-surfaced and mechanically stable alginate-poly(L-histidine) (PLHis) microcapsules with narrow particle size distributions were prepared by incubating calcium alginate beads in aqueous solutions of PLHis. The in vitro release characteristics, drug loading and encapsulation efficiency of the microcapsules were investigated using bovine erythrocytes hemoglobin (Hb) as a model drug. The results showed that the concentration of Ca(2+) ions had a considerable effect on the drug loading, encapsulation efficiency and in vitro release behavior of the microcapsules. When the concentration of CaCl(2) in the PLHis solution was increased from 0 to 3.0% (w/v), the drug loading and encapsulation efficiency decreased significantly from 38.0 to 4.3% and from 92.9 to 8.0%, respectively, while the total cumulative release of Hb from microcapsules in phosphate buffered saline solution (PBS, pH 6.8) decreased from 96.2 to 72.8% in 24 h. No significant protein release was observed during 70 h of incubation in hydrochloric acid solution (pH 1.2). However, under neutral conditions (PBS, pH 6.8), the Hb was completely and stably released within 24-70 h. An explosion test showed that the stability of alginate-PLHis microcapsules depended strongly on the concentration of PLHis and the calcium ions in solution. [Diagram: see text] Microscopy photo of Hb-loaded alginate-PLHis microcapsules.     

Coordination chemistry and biological activity of two tridentate ONS and NNS Schiff bases derived from S-benzyldithiocarbazate

Two tridentate Schiff bases having ONS and NNS donor sequences were prepared by condensing S-benzyldithiocarbazate (NH₂NHCSSCH₂Ph) (SBDTC) with pyridine-2-carboxaldehyde and salicylaldehyde, respectively. Complexes of these ligands with Ni^II, Zn^II, Cr^III, Co^II, Cu^II, and Sn^II were studied and characterized by elemental analyses and various physico-chemical techniques. Ni^II, Cu^II, Zn^II and Sn^II complexes were four-coordinate while the Cr^III, Sr^III and Co^III complexes were six-coordinate. The ONS Schiff base was moderately active against leukemia, while its zinc, antimony and cobalt complexes were strongly active against leukemic cells with DC₅₀ = 0.35–5.00.     

2-（1,3-Diphenylpropen-1,3-diolato）-1,3,2-（5-formylbenzo）dioxaborol： A ＇Whole-molecule Disorder＇ Crystal Structure

The boron atom in C22H15BO5 is O,O’-chelated by the anions in a tetrahedral geometry, with the planar five-and six-membered chelate rings being orthogonal to each other. The molecule lies on a two-fold rotation axis. The molecule is disordered with respect to another molecule in a 93:7 ratio; the treatment of the ‘whole-molecule disorder’ by employing a large number of restraints is described. Crystal data: C22H15BO5, monoclinic C2/c, a = 17.1804(5), b = 12.9409(4), c = 9.8842(3) , β = 124.832(2)o, V = 1803.82(9) 3 at –173 K.     

Developing a novel alkaline anion exchange membrane derived from poly(ether‐imide) for improved ionic conductivity

We have developed a novel alkaline anion exchange membrane derived from poly(ether‐imide) for improved ionic conductivity. The effects of several important parameters on the chloromethylation of the membrane were investigated. These parameters included reaction temperature, reaction time, concentration of chloromethylation agent, concentration of polymer, and the amount of catalyst. The quaternization of the synthesized chloromethylated polymer was studied as well. The results show that all the studied parameters exhibited significant impacts on chloromethylation. Among them, the concentration of the chloromethylation agent played a key role in increasing the chloromethyl functional group attachment onto the polymer. It was found that the gelation could be avoided if these reaction parameters were controlled. It was also found that using an appropriate quaternization approach could significantly improve the ionic conductivity and optimize the conductivity of the membrane even though the functional chloromethyl groups attached to the polymer are limited. Copyright © 2009 John Wiley & Sons, Ltd.     

An effective sequence characterized amplified region‐PCR method derived from restriction site‐amplified polymorphism for the identification of female Schistosoma japonicum of zoonotic significance

In the present study, restriction site‐amplified polymorphism (RSAP) markers were used to examine the genetic variability of Schistosoma japonicum isolates from different endemic provinces in mainland China. Of the 45 pairs of primers screened, 10 RSAP markers showed a clear banding pattern with good resolution; however, only six exhibited a polymorphism among different isolates. Among six RSAP markers, one pair of primers (R8+R10) was able to differentiate male and female parasites, and amplified one constant specific band for female S. japonicum isolates. The specific band was recovered, re‐amplified and sequenced, and a sequence of 162 bp was obtained. Based on this sequence, a pair of specific primers was designed and used to develop sequence characterized amplified region (SCAR)‐PCR assay for identification and differentiation of female S. japonicum isolates. The SCAR‐PCR assay allowed the specific identification of female S. japonicum, with no amplicons being amplified from male S. japonicum, Fasciola hepatica, Clonorchis sinensis, S. mansoni (male and female parasite). DNA sequencing confirmed the identity of the amplified products. The minimum amount of DNA detectable using SCAR‐PCR assay was 0.3 ng for female S. japonicum. The SCAR‐PCR was able to differentiate effectively the male and female S. japonicum worms collected from 12 geographical origins in eight endemic provinces, the gender of which was known based on the morphological and biological features. These results showed that SCAR‐PCR provides an effective tool for the sex differentiation studies of S. japonicum, identification of female S. japonicum, diagnosis and epidemiological survey of S. japonicum infections in animals and human.     

Systematic exploration of a rutile-type zinc(II)-phosphonocarboxylate open framework: the factors that influence the structure

To systematically explore the assembly mechanism of a rutile-type open framework of {[Zn(3)(pbdc)(2)]·2H(3)O}(n) (3) (H(4)pbdc = 5-phosphonobenzene-1,3-dicarboxylic acid) constructed by 3-connected pbdc ligands and 6-connected Zn(3)(CO(2))(4)(PO(3))(2) secondary building units (Zn(3)-SBUs), three major factors including solvothermal procedures, types of solvents and amines, are taken into consideration. Seven novel structures, namely {[Zn(5)(pbdc)(2)(OH)(2)(H(2)O)(4)]·4H(2)O}(n) (1), {[Zn(3)(pbdc)(2)·H(2)O]·(Htea)·H(3)O·2-5(H(2)O)}(n) (2), {[Zn(3)(pbdc)(2)](H(3)O)(2)(dma)}(n) (4), {[Zn(2)(pbdc)(taea)]·3H(2)O}(n) (5), {[Zn(3)(pbdc)(2)(Hpda)(2)]·2H(2)O}(n) (6), {[Zn(5)(pbdc)(2)(Hpbdc)(2)]·2H(2)pz·9H(2)O}(n) (7), {[Zn(3)(pbdc)(2)]·Hpd·H(3)O·4H(2)O}(n) (8) are obtained. The results indicate that the layered-solvothermal method and the isopropanol solvent play crucial roles in the construction of the special anionic open framework of [Zn(3)(pbdc)(2)](2-). Changing these two factors led molecular assembly away from the rutile-type open framework. However, amines play a variable role in the framework, which means that by using appropriate amines, molecular assembly could generate the open framework of [Zn(3)(pbdc)(2)](2-) with pores decorated by amines. These results suggest a different approach towards decorating pores in anionic frameworks with precise structural information.