A detailed chemical kinetic mechanism has been developed to describe the oxidation of small hydrocarbon and oxygenated hydrocarbon species. The reactivity of these small fuels and intermediates is of critical importance in understanding and accurately describing the combustion characteristics, such as ignition delay time, flame speed, and emissions of practical fuels. The chosen rate expressions have been assembled through critical evaluation of the literature, with minimum optimization performed. The mechanism has been validated over a wide range of initial conditions and experimental devices, including flow reactor, shock tube, jet-stirred reactor, and flame studies. The current mechanism contains accurate kinetic descriptions for saturated and unsaturated hydrocarbons, namely methane, ethane, ethylene, and acetylene, and oxygenated species; formaldehyde, methanol, acetaldehyde, and ethanol.

A Hierarchical and Comparative Kinetic Modeling Study of C1 − C2 Hydrocarbon and Oxygenated Fuels

Alcohol combustion chemistry

Electrochemical sensor and biosensor platforms based on advanced nanomaterials for biological and biomedical applications.

Applied Discriminant Analysis

ZnO-based nanostructured electrodes for electrochemical sensors and biosensors in biomedical applications

A novel electrochemical sensor based on Au@PANI composites film modified glassy carbon electrode binding molecular imprinting technique for the determination of melamine.

The article describes an electrochemical creatinine sensor that is based on a glassy carbon electrode (GCE) modified with a magnetic molecularly imprinted polymer (MMIP) and a composite consisting of nickel nanoparticles and polyaniline that was prepared by electropolymerization. Aniline and methacrylic acid were used as the bifunctional monomers, and creatinine was used as the template molecule. Electrochemical deposition was performed via cyclic voltammetry in the potential range from −0.3 V to 1.2 V and at a scan rate of 50 mV·s-1 over 20 cycles. The Ni@PANI NPs were characterized by scanning electron microscopy, FTIR, X-ray diffraction and thermogravimetric analysis. The Ni@PANI-modified GCE was characterized by cyclic voltammetry, electrochemical impedance spectroscopy and differential pulse voltammetry. Under optimized conditions, the sensor displays a linear response to creatinine in the 40 to 800 nM concentration range, with a 0.2 nM detection limit. The method was successfully applied to the detection of creatinine in urine mimic and in spiked urine samples.

Electrochemical creatinine sensor based on a glassy carbon electrode modified with a molecularly imprinted polymer and a Ni@polyaniline nanocomposite

Combinatorial chemistry, high-throughput and virtual screening technologies have been extensively used for discovering agrochemical leads from chemical libraries. The knowledge of the physicochemical properties of the marketed agrochemicals is useful for guiding the design and selection of such libraries. Since the earlier profiling of marketed agrochemicals, the number and types of marketed agrochemicals have significantly increased. Recent studies have shown the change of some physicochemical properties of oral drugs with time. There is a need to also profile the physicochemical properties of the marketed agrochemicals. In this work, we analyzed the key physicochemical properties of 1751 marketed agrochemicals in comparison with the previously-analyzed herbicides and insecticides, 106 391 natural products and 57 548 diverse synthetic libraries compounds. Our study revealed the distribution profiles and evolution trend of different types of agrochemicals that in many respects are broadly similar to the reported profiles for oral drugs, with the most marked difference being that agrochemicals have a lower number of hydrogen bond donors. The derived distribution patterns provided the rule of thumb guidelines for selecting potential agrochemical leads and also provided clues for further improving the libraries for agrochemical lead discovery.

Physicochemical Profiles of the Marketed Agrochemicals and Clues for Agrochemical Lead Discovery and Screening Library Development

Ethenol is a recently identified combustion intermediate. However, its chemistry remains unclear. In present work, the removal reactions of ethenol by H atom are investigated. The geometries of all species involved in the reaction are optimized at B3LYP/6-311++G(d,p), and their single point energies are extrapolated to the infinite-basis-set limit at the level CCSD(T). Energies are also calculated at G3B3, CBS-APNO, and CCSD(T)/6-311++G(3df, 2p) for comparison. A total of six elementary reactions, including four abstractions and two additions, with explicit transition states are investigated. The results show that the reactions are selective: for abstractions, the hydrogen atom, linked to the oxygen atom, is the most reactive; while for additions, the preferred carbon site is the head "CH(2)═". The rate constants are estimated in the temperature range 300-3000 K according to the conventional transition state theory with the Eckart tunneling model. The dominant channels are the two additions in the whole temperature range. The abstractions can be competitive at high temperature but still do not dominate. The calculated rate constants for the reverse reaction of (R6), syn-CH(2)═CHOH + H ↔ CH(3)·CHOH, are consistent with the available literature values. Finally, the Fukui functions are calculated to analyze the site reactivity.

Xianyin Zeng

Papers

A novel electrochemical sensor based on Au@PANI composites film modified glassy carbon electrode binding molecular imprinting technique for the determination of melamine.

Electrochemical creatinine sensor based on a glassy carbon electrode modified with a molecularly imprinted polymer and a Ni@polyaniline nanocomposite

Physicochemical Profiles of the Marketed Agrochemicals and Clues for Agrochemical Lead Discovery and Screening Library Development

Theoretical investigations on removal reactions of ethenol by H atom.

Research of protein adsorption on the different surface topography of the zinc oxide