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The fabrication of Ti3SiC2 from TiC-containing reactant compacts was investigated by combustion synthesis in the mode of self-propagating high-temperature synthesis (SHS). The initial sample composition was formulated based on (3 − x)Ti + ySi + (2 − x)C + xTiC + zAl, with stoichiometric parameters of x from 0 to 0.7, y = 1.0 and 1.2, and z = 0 and 0.1. For all samples studied, combustion was sufficiently exothermic to sustain the reaction in the SHS manner. Due to the dilution effect of TiC, combustion wave velocity and reaction temperature substantially decreased with TiC content. When compared with the TiC-free sample, the TiC-containing sample facilitated the formation of Ti3SiC2 and the TiC content of x = 0.5 produced the highest yield. Excess Si (y = 1.2) to compensate for the evaporation loss of Si during combustion and the addition of Al (z = 0.1) to promote the phase conversion were effective in improving the evolution of Ti3SiC2. All final products were composed of Ti3SiC2, TiC, and Ti5Si3. For the TiC-containing samples of x = 0.5, the weight fraction of Ti3SiC2 increased from 67 wt.% in the sample without extra Si and Al to 72 wt.% in the Si-rich sample of y = 1.2 and further up to 85 wt.% in the Si-rich/Al-added sample of y = 1.2 and z = 0.1. As-synthesized Ti3SiC2 grains were in a thin plate-like shape with a thickness of 0.5–1.0 μm and length of about 10 μm. Ti3SiC2 platelets were closely stacked into a layered structure. [ABSTRACT FROM AUTHOR]

This study investigates the relation between information transparency and idiosyncratic risk with the unique and nonpublic data of listed companies violating the material information disclosure rules in Taiwan. This study employs the violated companies that do not report or delay the disclosure of material information as sample of worse information transparency. The results show that the companies with worse information transparency have higher idiosyncratic risk and total risk than other companies. The negative connection between information transparency and idiosyncratic risk implies that the current regulations of material information disclosure in Taiwan work efficiently. [ABSTRACT FROM PUBLISHER]

Purpose – This study aims to investigate whether and how different sentiments affect the stock market’s reaction to the American Customer Satisfaction Index (ACSI) information. Design/methodology/approach – The portfolio approach, with time-varying risk factor loadings and the asset-pricing models, is borrowed from the finance literature to investigate the ACSI-performance relationship. A direct sentiment index is used to examine how investors’ optimistic, neutral and pessimistic sentiments affect the aforementioned relation. Findings – This paper finds that customer satisfaction is a valuable intangible asset that generates positive abnormal returns. On average, investing in the Strong-ACSI Portfolio is superior to investing in the market index. Even when the stock market holds pessimistic beliefs, investors can beat the market by investing in firms that score well on customer satisfaction. The out-performance of our zero-cost, long–short ACSI strategy also confirms the mispricing of ACSI information in pessimistic periods. Research limitations/implications – Findings are limited to firms covered by the ACSI data. Practical implications – Finance research has further documented evidence of the stock market under-reacting to intangible information. For example, firms with higher research and development expenditures, advertising, patent citations and employee satisfaction all earn superior returns. Literature also proves that investors efficiently react to tangible information, whereas they undervalue intangible information. In summary, combining our results and those reported in the literature, customer satisfaction is value-relevant for both investors and firm management, particularly in pessimistic periods. Originality/value – This study is the first to investigate how sentiment affects the positive ACSI-performance relationship, while considering the time-varying property of risk factors. This study is also the first to show that ACSI plays a more important role during pessimistic periods. This study contributes to the growing literature on the marketing–finance interface by providing better understanding of how investor emotional states affect their perceptions and valuations of customer satisfaction. [ABSTRACT FROM AUTHOR]

In this study, silica-coated magnetic nanoparticles (SiMNPs) with isocyanatopropyltriethoxysilane as a metal-chelating ligand were prepared for the immobilization of His6-tagged Escherichia coli prolidase (His6-EcPepQ). Under one-hour coupling, the enzyme-loading capacity for the Ni2+-functionalized SiMNPs (NiNTASiMNPs) was 1.5 mg/mg support, corresponding to about 58.6% recovery of the initial activity. Native and enzyme-bound NiNTASiMNPs were subsequently characterized by transmission electron microscopy (TEM), superparamagnetic analysis, X-ray diffraction, and Fourier transform infrared (FTIR) spectroscopy. As compared to free enzyme, His6-EcPepQ@NiNTASiMNPs had significantly higher activity at 70 °C and pH ranges of 5.5 to 10, and exhibited a greater stability during a storage period of 60 days and could be recycled 20 times with approximately 80% retention of the initial activity. The immobilized enzyme was further applied in the hydrolysis of two different organophosphorus compounds, dimethyl p-nitrophenyl phosphate (methyl paraoxon) and diethyl p-nitrophenyl phosphate (ethyl paraoxon). The experimental results showed that methyl paraoxon was a preferred substrate for His6-EcPepQ and the kinetic behavior of free and immobilized enzymes towards this substance was obviously different. Taken together, the immobilization strategy surely provides an efficient means to deposit active enzymes onto NiNTASiMNPs for His6-EcPepQ-mediated biocatalysis. [ABSTRACT FROM AUTHOR]