113 research outputs found

    Highly enhanced catalytic stability of copper by the synergistic effect of porous hierarchy and alloying for selective hydrogenation reaction

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    Supported copper has a great potential for replacing the commercial palladium-based catalysts in the field of selective alkynes/alkadienes hydrogenation due to its excellent alkene selectivity and relatively high activity. However, fatally, it has a low catalytic stability owing to the rapid oligomerization of alkenes on the copper surface. In this study, 2.5 wt% Cu catalysts with various Cu:Zn ratios and supported on hierarchically porous alumina (HA) were designed and synthesized by deposition–precipitation with urea. Macropores (with diameters of 1 μm) and mesopores (with diameters of 3.5 nm) were introduced by the hydrolysis of metal alkoxides. After in situ activation at 350 °C, the catalytic stability of Cu was highly enhanced, with a limited effect on the catalytic activity and alkene selectivity. The time needed for losing 10% butadiene conversion for Cu1Zn3/HA was ~40 h, which is 20 times higher than that found for Cu/HA (~2 h), and 160 times higher than that found for Cu/bulky alumina (0.25 h). It was found that this type of enhancement in catalytic stability was mainly due to the rapid mass transportation in hierarchically porous structure (i.e., four times higher than that in bulky commercial alumina) and the well-dispersed copper active site modified by Zn, with identification by STEM–HAADF coupled with EDX. This study offers a universal way to optimize the catalytic stability of selective hydrogenation reactions

    System Design and Optimisation Study on a Novel CCHP System Integrated with a Hybrid Energy Storage System and an ORC

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    For achieving higher energy transferring efficiency from the resources to the load, the Combined Cooling, Heating, and Power (CCHP) systems have been widely researched and applied as an efficient approach. The key idea of this study is designing a novel structure of a hybrid CCHP system and evaluating its performance. In this research, there is a hybrid energy storage unit enhancing the whole system’s operation flexibility while supplying cooling, heating, and power. An ORC system is integrated into the CCHP system which takes responsibility of absorbing the low-temperature heat source for electricity generation. There are a few research studies focusing on the CCHP systems’ performance with this structure. In order to evaluate the integrated system’s performance, investigation and optimisation work has been conducted with the approaches of experimental studies and modelling simulation. The integrated system’s configuration, the model building process of several key components, the optimisation method, and the case studies are discussed and analysed in this study. The design of the integrated system and the control strategy are displayed in detail. Several sets of dynamic energy demand profiles are selected to evaluate the performance of the integrated system. The simulation study of the system supplying selected scenarios of loads is conducted. A comprehensive evaluation report indicates that the system’s efficiency during each study process differs while supplying different loads. The results include the power supplied by each component, the energy consumed by each type of load, and the efficiency improvements. It is found that the integrated system fully satisfies the selected domestic loads and various selected scenarios of loads with high efficiency. Compared to conventional power plants or CHP systems, the system efficiency enhancement comes from higher amount of recovery waste heat. Especially, the ORC system can absorb the low-temperature heat source for electricity generation. Compared to the original following electrical load (FEL) control strategy, the optimisation process brings overall efficiency improvements. The system’s overall efficiency was increased by from 3%, 3.18%, 2.85%, 17.11%, 8.89%, and 21.7% in the second case studies. Through the whole study, the main challenge lies within the design and the energy management of the integrated system

    Probability weighting and asset prices: evidence from mergers and acquisitions

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    For mergers and acquisitions with a small failure probability, the average decline in target stock price if the deal fails is much larger than any increase that accompanies deal success. Probability weighting implies that the deal failure probability of such target stocks will be overweighted, leading them to be undervalued. I test whether investors are averse to holding such stocks and find strong supporting evidence. Target stocks with lower ex-ante failure probability yield positive abnormal returns, but other targets do not generate significant abnormal returns. A trading strategy that buys target stocks with low ex-ante failure probability and sells short target stocks with high ex-ante failure probability delivers around 1% abnormal return per month. These abnormal returns are not subsumed by a preference for positive skewness under traditional (expected) utility models; in fact, target stocks with lower ex-ante failure probability have lower betas, lower volatilities, and lower downside risk. I also find that profits from the strategy are significantly higher when arbitrage is more difficult

    The Nominal Price Premium

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    Nominal price illusion

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    Recent work finds that nominal prices influence investor behavior. Why prices matter to investors, however, is a question that is as of yet unanswered. We provide evidence that investors suffer from a nominal price illusion in which they overestimate the “room to grow” for low-priced stocks relative to high-priced stocks. Investor expectations of future skewness increase drastically on days that a stock undergoes a split to a lower nominal price. However, in practice future physical skewness decreases. In the cross-section of stocks, we find that investors overweight the importance of price in their skewness expectations. Asset pricing implications of our findings are borne out in the options market. A zero-cost option portfolio strategy that exploits skewness overestimation for low-priced stocks relative to high-priced stocks earns economically and statistically significant returns

    Overseas Listing Locations and Capital Structure

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    Purpose – A significant number of Chinese companies are listed overseas. The authors aim to examine whether overseas locations affect their financing decision, specifically their capital structure choice. Design/methodology/approach – Most of the Chinese overseas listed companies are listed in the USA and Hong Kong. As the institutional quality of the USA is better than Hong Kong, the authors, therefore, choose to build the hypotheses from the “law and finance” literature. Specifically, the authors argue that the better institutional environment of the USA can mitigate the information asymmetry problem and the agency problem of financing via equity. Consequently, firms listed in the USA will rely more on equity and have lower leverage ratio. The difference in leverage ratio of US listed and Hong Kong listed companies should be larger when the marginal benefit of better information environment is larger. Findings – Referring to various data sources, the authors construct a comprehensive list of overseas listed companies in the USA and Hong Kong. The authors collect the accounting and stock performance information from Datastream/Worldscope and the equity offering data from Global New Issue database. The empirical findings provide strong support of the hypotheses: the leverage is 15 percent lower for US listed companies than the Hong Kong listed companies; the results are stronger when the firms face more severe information asymmetry problem; the stock price reacts less negatively for seasoned equity offering in the USA than in Hong Kong. Practical implications – Most of the Chinese companies decided to be listed overseas because they cannot be listed in the Mainland Chinese stock exchanges. One of the most important motivation is to access to external capital to support firm growth. As the main channel of external financing in the overseas markets is equity since debt is still mainly domestically based, one implication of this paper is that Chinese companies can gain better access to external capital in the USA than in Hong Kong and relax their financial constraint. Originality/value – There are a considerable number of Chinese companies listed in the overseas markets. Many successful and famous companies are among them. However, almost no research has been done based on them. This paper documents some very important phenomenon of this market. The authors wish that more studies will be conducted. In addition, the study also complements the existing studies on how institutional environment affects corporate financial behavior
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