Preparation and characterization of poly(copper 2,3,9,10,16,17,23,24-octacyanophthalocyanine)

Dark blue poly(copper 2,3,9,10,16,17,23,24-octacyanophthalocyanine) has been prepared by reacting 1,2,4,5-tetracyanobenzene with cuprous chloride in 1-methyl-2-pyrrolidone at ca. 150°C. The product has been characterized by elemental analysis, thermal analysis, infrared and UV-VIS spectroscopies. The polymer has high purity and exhibits good thermal stability in an inert atmosphere.     

Microwave-accelerated metal-enhanced fluorescence: application to detection of genomic and exosporium anthrax DNA in <30 seconds

We describe the ultra-fast and sensitive detection of the gene encoding the protective antigen of Bacillus anthracis the causative agent of anthrax. Our approach employs a highly novel platform technology, Microwave-Accelerated Metal-Enhanced Fluorescence (MAMEF), which combines the use of Metal-Enhanced Fluorescence to enhance assay sensitivity and focused microwave heating to spatially and kinetically accelerate DNA hybridization. Genomic and exosporium target DNA of Bacillus anthracis spores was detected within a minute in the nanograms per microliter concentration range using low-power focused microwave heating. The MAMEF technology was able to distinguish between B. anthracis and B. cereus, a non-virulent close relative. We believe that this study has set the stage and indeed provides an opportunity for the ultra-fast and specific detection of B. anthracis spores with minimal pre-processing steps using a relatively simple but cost-effective technology that could minimize casualties in the event of another anthrax attack.     

The Measurement of Dextran in Raw Sugars Using 1H NMR1

Abstract

In the cane sugar industry the purchase price of raw cane sugar, the product of sugar cane processing, is determined by polarimetric measurement of sucrose content in raw sugar solutions, expressed as Pol. Raw sugar generally contains more than 96% sucrose, but also contains other saccharides and non-sugars which can contribute to Pol. Dextrans, one class of polysaccharides often found in raw sugar, effect an increase in Pol and interfere with subsequent refining. The U.S. sugar refining industry can impose a penalty on the raw sugar purchase price for high dextran content. While there are several wet chemical methods for the determination of dextran in raw sugar, the results of these analyses are rarely in agreement. The existing wet chemical methods for the determination of dextran in raw cane sugar are reviewed and the results of these wet chemical analyses are compared with the results obtained from the physical measurement of dextran in raw sugar by ¹H NMR spectroscopy.     

Automatic simulation of electrochemical transients by the adaptive Huber method for Volterra integral equations involving Kernel terms exp[?α(t ? τ)]erex{[β(t ? τ)]1/2} and exp[?α(t ? τ)]daw {[β(t ? τ)]1/2}

Development of fully automatic methods for the simulation of transient experiments in electroanalytical chemistry is a desirable element of the contemporary trends of laboratory automation in electrochemistry. In accord with this idea, the adaptive Huber method, elaborated by the present author, is intended to solve automatically integral equations of Volterra type, encountered in the theory of controlled-potential transients. The coefficients of the method have been recently obtained for integral transformation kernels involving terms K(t, τ) = exp[−α(t − τ)]erex{[β(t − τ)]^1/2} and K(t, τ) = exp[−α(t − τ)]daw{[β(t − τ)]^1/2} with α ≥ 0 and β ≥ 0, which are known to occur in the above integral equations. In this work the validity of the resulting method, for electrochemical simulations, is examined using representative examples of electroanalytical models involving integral equations with various special cases of such kernel terms. The performance of the method is found similar to that previously reported for integral equations involving exclusively kernels K(t, τ) = 1, K(t, τ) = (t − τ)^−1/2, and K(t, τ) = exp[−λ (t − τ)](t − τ)^−1/2 with λ > 0.     

Polarization and image rotation induced by a rotating dielectric rod: an optical angular momentum interpretation

When light is transmitted along the axis of a rotating glass rod, the polarization of the light is rotated through a small angle [Proc. R. Soc. London, Ser. A349, 423 (1976)]. Under the same conditions, we predict a rotation of the transmitted image by exactly the same angle. The treatment of the two effects in terms of light's spin and orbital angular momentum suggests that they share a common origin.