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In this paper, the prenyl alcohol was catalyzed synthesized by using isoprene and dichloroacetic acid as raw material and sodium dichloroacetate as catalyst. The obtained product was mainly characterized by FT-IR and GC. Furthermore, the olefine acid ratio, reaction time, amount of catalyst, saponification time, NaOH concentration and distilled water consumption were systematically investigated during the work. The optimum reaction conditions were as follows: the olefine acid ratio was 1:2, reaction time was 2h, amount of catalyst was 1.5g, saponification time was 2h, NaOH concentration was 4mol/L and amount of distilled water was 0.2mL, the yield of prenyl alcohol was 26%

This work suggests a facile method to improve the thermoelectric properties of polyaniline (PANi) composites. Carbon multiwall nanotubes (MWNTs) were noncovalently functionalized with polypyrrole (PPy-MWNTs) based on in situ polymerization, and these PPy-MWNTs were used to synthesize PPy-MWNT/PANi composites. The surface-functionalized PPy nanolayer on the MWNTs was found to yield a homogeneous dispersion of MWNTs and strong interfacial adhesion. The resulting composites demonstrated a remarkable enhancement in both electrical conductivity and Seebeck coefficient, and exhibited a high power factor of 3.1 μW/m K2 compared with the values of 0.006 μW/m K2 for PANi and 0.1 μW/m K2 for MWNT/PANi composite at 28.6 wt.% MWNT loading. The obtained results indicate that this method is useful for synthesizing conductive polymer composites with improved thermoelectric performance.

Cloud computing has emerged as a widely accepted computing paradigm over the past few years. With the increasing application of cloud computing in vast areas such as industry, transportation and healthcare, the reliability of application systems draws special attention. However, due to the complexity of cloud computing system in structural and behavioral aspects, it is a great challenge to guarantee the reliability of applications in cloud environment. In this paper, we investigate the fault tolerant strategy and model for cloud computing. By constructing the extensible fault models of cloud computing systems, we can characterize the mechanisms of cloud computing, the fault behaviors of component, the cooperation and competition relations between cloud applications. Considering the fault and service resource of cloud computing, we solve the Nash equilibrium of the model and optimize the recovery program of cloud computing and propose the fault migration and restoration schemas for cloud computing. By considering the fault time and its cost, we compute the utility of the components of cloud computing and cloud application, and further analyze the benefits of cloud application. In order to optimize the fault tolerant effectiveness of cloud computing, we solve the Nash equilibrium of model. Model checking techniques are used to verify the correctness of fault diagnosis and recovery. This research is of both theoretical and practical significance in revealing structural and behavioral characteristics of cloud computing, and improving reliability of cloud computing systems.

In this paper, the prenyl alcohol was catalyzed synthesized in anhydrous system by using isoprene and dichloroacetic acid as raw material and sodium dichloroacetate as catalyst. The obtained product was mainly characterized by FT-IR and GC. Furthermore, the olefine acid ratio, reaction time, amount of catalyst, saponification time and NaOH concentration were systematically investigated during the work. The optimum reaction conditions are as follows: the olefine acid ratio was 1:2, reaction time was 2h, amount of catalyst was 1.8g, saponification time was 2h and NaOH concentration was 4mol/L, the yield of prenyl alcohol was 45%.

The improved synthesis of 3, 3-dimethyl-4-pentenoic acid methyl ester (DPE) had been discovered. In new process, orthophosphate (85%) and sodium methoxide(98%)was used as catalysts at different stages of the reaction, the amount of azeotropic mixture of DPE and the byproduct 3'-methyl-2'-butenyl-3, 3-dimethyl-pentenpate (MBDP) is reduced, the recovery rate of product DPE is improved. under the optimal reaction condition, the highest yield of DPE approach 84%. Improved the process is more suitable for industrial production.

Software fault tolerance makes system complicated by means of diverse fault-tolerant mechanisms. Aspect-oriented programming has been confirmed as a well suited candidate to ease the problem. However, most of the existing works only focus on implementation level. This paper proposes an AOFTM model for aspect-oriented fault tolerance modeling with Coloured Petri nets at design level. Moreover, the weaving mechanism formally defined conducts the way to derive a woven net from AOFTM. A case study presents how AOFTM works, and its properties are analyzed using the CPN Tools.

The new process of 1-(3,4-dichloropheny)-3-methyl-pyrazolone-5-one (34DCPMP) synthesis had been discovered, which using 3,4-dichloro phenylhydrazine hydrochloride(DCPH) and ethyl acetoacetate as the raw material , The product was obtained by the route during cyclization in aqueous medium. The structure of products was confirmed by 1HNMR, 13CNMR and IR. The effects of factors on the yield of products were investigated. It was found that the yield of 34DCPMP can reach 98.7% under the optimal reaction condition of n(34DCPH):n(ethyl acetoacetate) with 1:1.1, n(34DCPH):n(Na2SO3) with 1.3:1 at 80°C, and pH 7.5 for 3h. The chromatographic purity can be higher than 98.2%.