The usage of m-CPBA (meta-chloroperbenzoic acid) is limited on large scale due to its thermal instability, although it is a good oxidant and well-accepted in laboratory scale. In our recent project, m-CPBA was used for an oxidation reaction, and an explosion hazard was identified. To ensure the safe use of m-CPBA on large scale, the stability of m-CPBA in different solvents was investigated, and it was found that besides the incompatibility between m-CPBA and DMF reported earlier, the intrinsic instability of m-CPBA/DCM solution at high concentration (low onset temperature and large exotherm) can also cause a major problem on large scale. Therefore, process parameters such as concentration of m-CPBA, addition sequence, and handling temperature have been investigated and successfully applied in pilot plant for a large scale reaction using 8 kg of m-CPBA.

A newly synthesized oligothiophene surfactant self-assembles into unilamellar vesicles in aqueous solution and exhibits semiconductive behavior as a cast film.

We propose a numerical method for calculating exact all‐time apparent resistivity for time‐domain transient electromagnetic method. According to the behaviour of the kernel function Y'(Z) for  ∂Bz/∂T, the transient can be distinguished into early‐time (Z > 1.6), transition point (Z = 1.6) and late‐time (Z < 1.6) stages for a central loop configuration. First the exact early‐time and late‐time apparent resisitivities are calculated using the earlytime and late‐time expressions , then the exact all‐time curve is founded by combining the two over the transition point. Although the kernel function Y (Z) for BZ is single valued, there is also a transition point Z = 1.6 and the early‐time and late‐time expressions should be used for Z > 1.6 and Z ≤ 1.6, respectively. For the numerical calculation an iterative procedure is employed. The relative error in the all‐time apparent resistivity will be less than 0.5% when the variation of the parameter Z is defined as ΔZ < 0.005Z in the iteration. Model calculation and field data experiments show that the resulting all‐time apparent resistivity can be easily determined with greater accuracy and higher resolution than that based on early‐time and late‐time asymptotic definitions.

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In this paper, we study the effective capacity (EC) which was proposed to measure the quality of service (QoS) for fading channels. A unified expression for the effective capacity based on the method of moment generating function (MGF) is proposed. The unified expression applies to various fading channels and is derived for both single antenna and multiple antenna diversity system. The mathematical expression is illustrated with Nakagami-m fading channels and closed form expressions are derived in this case. The simulation results verify the consistence of the closed-form expressions with numerical evaluations.