Microwave-Assisted Synthesis,Crystal Structure and Magnetic Behavior of a Schiff Base Heptanuclear Cobalt Cluster

The reaction of Co(ClO₄)₂·6H₂O with 2-hydroxy-3-methoxy-benzaldehyde and an aqueous solution of methylamine in acetonitrile/MeOH under microwave irradiation and controlled temperature/pressure leads to formation of heptanuclear cobalt cluster [Co₇(mmp)₆(CH₃O)₆]·(ClO₄)₂ (1) (mmp is 2-methoxy-6-methyliminomethyl-phenol anion) in only 20 min and also results in higher yields in contrast to other synthesis methods. Complex 1 displays dominant ferromagnetic interactions through μ ₃-O and μ ₂-O (oxidophenyl) binding modes.     

Syntheses and Crystal Structures of Two New Pentaborates Templated by Transition-Metal Complexes

Two new pentaborates [M(dap)₃][B₅O₆(OH)₄]₂·H₂O (M = Co (1) and Ni (2); dap = 1,2-diaminopropane) have been hydrothermally synthesized. Both structures were determined by single crystal X-ray diffraction and further characterized by elemental analysis, FT-IR, thermogravimetric analysis and photoluminescence spectroscopy. Two compounds are isostructural and consist of isolated pentaborate [B₅O₆(OH)₄]^? anions and [M(dap)₃]²⁺ complex cations. The anionic [B₅O₆(OH)₄]^? groups are linked by extensive hydrogen bonds to form a 3-D supramolecular framework with large channels, in which the transition-metal complex templates are located. The luminescent properties of 1 and 2 were studied, and blue luminescence occurs with an emission maximum at 405 and 408 nm upon excitation at 332 and 328 nm respectively. Crystal data: 1, monoclinic, space group P2₁/c (No. 14), a = 9.7159(5) Å, b = 29.3372(19) Å, c = 11.5121(6) Å, β = 103.286(5)°, V = 3193.6(3) ų, Z = 4; 2, monoclinic, space group P2₁/c, a = 9.7264(4) Å, b = 29.3810(16) Å, c = 11.5185(6) Å, β = 103.249(4)°, V = 3204.0(3) ų, Z = 4.     

4‐Benzamido‐TEMPO Catalyzed Oxidation of a Broad Range of Alcohols to the Carbonyl Compounds with NaBrO3 under Mild Conditions

4‐Benzamido‐TEMPO catalyzed oxidation system for conversion of a wide range of alcohols to the aldehydes or ketones with NaBrO₃ under room temperature conditions has been developed. The credible, operationally convenient and economical, and condition mild oxidation protocol is particularly of interest in laboratory and in fine chemicals manufacture.     

Quantum Dots for Display Applications

This article offers a materials-chemistry perspective for colloidal quantum dots (QDs) in the field of display, including QD-enhanced liquid-crystal-display (QD-LCD) and QD-based light-emitting-diodes (QLEDs) display. The rapid successes of QDs for display in the past five years are not accidental but have a deep root in both maturity of their synthetic chemistry and their unique chemical, optical, and optoelectronic properties. This article intends to discuss the natural match of QD emitters for display and chemical means to eventually bring about their full potential.     

Separation of micro and sub-micro diamagnetic particles in dual ferrofluid streams based on negative magnetophoresis

In the present study, we numerically demonstrate an approach for separation of micro and sub-micro diamagnetic particles in dual ferrofluid streams based on negative magnetophoresis. The dual streams are constructed by an intermediate sheath flow, after which the negative magnetophoretic force induced by an array of permanent magnets dominates the separation of diamagnetic particles. A simple and efficient numerical model is developed to calculate the motions of particles under the action of magnetic field and flow field. Effects of the average flow velocity, the ratio of sheath fluid flow to sample fluid flow, the number of the magnet pair as well as the position of magnet pair are investigated. The optimal parametric condition for complete separation is obtained through the parametric analysis, and the separation principle is further elucidated by the force analysis. The separation of smaller micro and sub-micro diamagnetic particles is finally demonstrated. This study provides an insight into the negative magnetophoretic phenomenon and guides the fabrication of feasible, low-cost diagnostic devices for sub-micro particle separation.     

Insights into the interactions between DNA and an infinite clamp-like copper (II) complex

Transition Metal Chemistry - A Cu(II) complex [Cu2(phen)2(NAB)2(HO)]n (phen?=?1, 10-phenanthroline and NABH?=?p-N, N-(2-hydroxyethyl)amino benzoic acid) was synthesized, and...     

A literature review on the in situ generation of reinforcing fibers

Liquid crystal polymers (LCPs) are a relatively new class of materials. These polymers usually consist of rigid rodlike molecular chains and they are capable of forming highly oriented structures even in the as-made product, with strength/modulus significantly higher than those of the conventional flexible chain polymers. Blending of LCPs with conventional polymers produces composite-like structures with LCPs serving as the reinforcing component. The properties of the blends are affected by the size, shape and distribution of the LCPs in the matrix polymer, which in turn are related to the processing conditions such as the blend composition, the extrusion and drawing conditions, the viscosity ratio of the component polymers and the type and grade of the LCPs and the matrix polymers. Improved processability of the blend due to the reduction in viscosity and the improved interfacial adhesion between reinforcing fibers and the matrix polymer are among the advantages of these materials over the conventional short fiber reinforced composites. This paper gives a brief review of the work currently available in the literature on rheology, fabrication, blend morphology and mechanical/thermal properties of the in situ composites from blends of LCPs and conventional polymers.     

An applied research on approach of dyadic wavelet transform for Remote Sensing image edge detection

In the edge detection of Remote Sensing （RS） image, the useful detail losing and the spurious edge often appear. To solve the problem, the authors uses the dyadic wavelet to detect the edge of surface features by combining the edge detecting with the multi-resolution analyzing of the wavelet transform. Via the dyadic wavelet decomposing, the RS image of a certain appropriate scale is obtained, and the edge data of the plane and the upright directions are respectively figured out, then the gradient vector module of the surface features is worked out. By tracing them, the authors get the edge data of the object, therefore build the RS image which obtains the checked edge. This method can depress the effect of noise and examine exactly the edge data of the object by rule and line. With an experiment of an RS image which obtains an airport, the authors certificate the feasibility of the application of dyadic wavelet in the object edge detection.     

Discovery of Novel Non-Oxime Reactivators Showing In Vivo Antidotal Efficiency for Sarin Poisoned Mice

A family of novel efficient non-oxime compounds exhibited promising reactivation efficacy for VX and sarin inhibited human acetylcholinesterase was discovered. It was found that aromatic groups coupled to Mannich phenols and the introduction of imidazole to the ortho position of phenols would dramatically enhance reactivation efficiency. Moreover, the in vivo experiment was conducted, and the results demonstrated that Mannich phenol L10R1 (30 mg/kg, ip) could afford 100% 48 h survival for mice of 2*LD₅₀ sarin exposure, which is promising for the development of non-oxime reactivators with central efficiency.     

A Study of the Role of Microfractures in Counter-Current Spontaneous Imbibition by Lattice Boltzmann Simulation

Transport in Porous Media - During waterflooding, spontaneous imbibition is a fundamental recovery mechanism in fractured reservoirs. A large number of numerical and experimental studies have been...