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In this study, a different approach is introduced to generate the kinetic sub-model for the modeling of solid-state pyrolysis reactions based on the thermogravimetric (TG) experimental data over a specified range of heating rates. Gene Expression Programming (GEP) is used to produce a correlation for the single-step global reaction rate as a function of determining kinetic variables, namely conversion, temperature, and heating rate.

For a case study on the coal pyrolysis, a coefficient of determination (R²) of 0.99 was obtained using the generated model according to the experimental benchmark data. Comparison of the model results with the experimental data proves the applicability, reliability, and convenience of GEP as a powerful tool for modeling purposes in the solid-state pyrolysis reactions.

The resulting kinetic sub-model takes advantage of particular characteristics, to be highly efficient, simple, accurate, and computationally attractive, which facilitates the CFD simulation of real pyrolizers under isothermal and non-isothermal conditions.

It should be emphasized that the above-mentioned manuscript is not under evaluation in any journals and submitted exclusively for consideration for possible publication in this journal. The generated kinetic model is in the final form of an algebraic correlation which, in comparison to the conventional kinetic models, suggests several advantages: to be relatively simpler, more accurate, and numerically efficient. These characteristics make the proposed model computationally attractive when used as a sub-model in CFD applications to simulate real pyrolizers under complex heating conditions.

This study aims to empirically analyze the market response of energy companies to the Russian-Ukrainian invasion. Additionally, it examines the comparison of market reactions between companies in NATO member countries and non-member countries.

This study utilizes a sample of 1,511 energy sector companies. To achieve the research objectives, two methods are employed. First, an event study is used to analyze the market reaction using Cumulative Abnormal Return (CAR) to the announcement of Russia's invasion of Ukraine on February 24, 2022 (event day) within an event window of (−30, +30). Second, a cross-sectional analysis is conducted to compare the responses of companies in NATO member countries with those in non-member countries.

The findings of this study reveal that energy companies worldwide reacted positively both before and after the announcement of the invasion, with significant reactions observed in companies from the Americas, Europe, and Asia & Pacific regions. However, the Middle East and Africa markets did not show significant reactions. Furthermore, the study indicates that most developed and emerging markets responded positively, likely due to the increase in energy commodity prices during the war. Moreover, the market reaction of companies in NATO member countries was stronger compared to other markets.

This study contributes to the existing literature by being the first to examine the impact of the Russian invasion of Ukraine on the energy sector, while categorizing markets as developed, emerging, and frontier. It also specifically explores the market reaction of energy companies in NATO member countries, providing unique insights into the differential responses within the energy sector.

研究目的: 本研究擬以經驗及觀察為依據, 去分析能源公司對俄羅斯–烏克蘭侵略行為的市場反應。研究亦擬進行關於北約成員國內的能源公司及非成員國內的能源公司的市場反應的比較研究。

研究設計/方法/理念: 研究使用的樣本為1511間能源領域內的公司。研究人員為能達到研究目標, 採用了兩個方法。首先, 他們使用事件研究法進行有關的研究。具體地說, 他們以累積異常報酬率, 來分析在 (−30, +30) 的事件視窗之內, 能源公司對俄羅斯於2022年2月24日 (事發日) 入侵烏克蘭的公告的市場反應。其次, 研究人員以橫向分析法, 就北約成員國內的能源公司及非成員國內的能源公司的反應進行比較研究。

研究結果: 研究結果顯示, 全球的能源公司於侵略行為公告前後均有正面的反應;而反應較為顯著的公司均來自美洲、歐洲和亞洲及太平洋地區。唯中東和非洲市場均沒有顯著的反應。研究結果亦顯示, 大多數已發展市場和新興市場, 均有正面的反應, 這很可能是因為於戰爭期間, 能源商品價格上升所致。再者, 北約成員國內的公司的市場反應較其他市場強烈。

研究的原創性: 本研究率先以已開發市場、新興市場和邊境市場的市場分類, 去探討俄羅斯入侵烏克蘭對能源部門的影響;就此, 本研究對現有文獻作出了貢獻。研究亦特意探索了北約成員國內能源公司及非成員國內的能源公司兩者的市場反應, 這給我們獨特的啟示, 以能了解能源領域內各種不同的反應。

Many of the industrially important processes follow a complex reaction scheme and more than one reaction takes place simultaneously for these systems. Design and scale up of these processes are important but due to the nature of the system and high numbers of the affected parameters, modeling of the complex reactions becomes correspondingly difficult. The purpose of this paper is to develop a general model, which can simplify modeling of such (or similar) complex reactions.

Virtual model is a generalized novel approach for modeling of these complex reactions. In this model, the complex reactions have been imagined as a simple reaction. Now, kinetic and structural parameters of this simple reaction have been obtained by fitting the model relationships with the experimental data.

In this work, the ability of the virtual model has been validated using the experimental data pertinent to the reduction of molybdenum disulfide and cuprous sulfide by hydrogen in the presence of lime.

Virtual model is a generalized novel approach for modeling of these complex reactions. In this model, the complex reactions have been imagined as a simple reaction.

The purpose of this paper is to present the results of studies on the reaction of metal oxides such as Cr₂O₃ and Al₂O₃ with Na₂SO₄ in flowing SO₂ (g) at 1,100 and 1,200 K.

The oxides chosen for the studies were initial scaling products during the oxidation of industrial alloys and invariably are involved in hot‐corrosion reactions in the presence of molten salts. The thermo‐gravimetric studies for the system were carried out as a function of Na₂SO₄ in the mixture. The different constituents in the reaction products were identified by XRD analysis and morphologies of the reaction products were discussed on the basis of optical metallography and scanning electron microscopic studies. The pH and conductivity of the aqueous solutions of reaction products were measured and an attempt made to functionalize these parameters with Na₂SO₄ concentration in the mixture. Quantitative estimation of the soluble metal was carried out using an atomic absorption spectrophotometer. The formation of products was investigated by thermodynamic computation of free energies of the reactions and the study of relevant phase stability diagrams.

Looking at the complex nature of the reactions, it is difficult to generalize the conductance studies, as many complex species are liable to hydrolyze in the aqueous solution. However, the break in few curves at certain mole fraction of Na₂SO₄ indicates the presence of soluble complex species.

The paper provides information regarding the reaction between a pertinent oxide and Na₂SO₄ and proper identification of reaction products, useful for understanding the occurrence and importance of fluxing reactions and in the interpretation of hot corrosion mechanism and the development of new protective materials.

Based on the theory of blown‐ups, in this paper, we will analyze chemical reaction problems, such as the rate of chemical reactions, gaseous chemical reactions, liquid chemical reactions, Schlogl’s model and the reaction diffusion equation. This study not only applies the theory of blown‐ups, but also offers a new method and a new thinking logic for nonlinear chemical dynamics. And, in a certain sense, this study brings new insight to the chemical dynamics and related research in laboratories.

Human beings are dependent upon social approval to strengthen their identities. Therefore, they practice impression management: They anticipate which behaviour provokes which reactions in their social environment, and they tend to exhibit the kind of behaviour that promises positive feedback. Based on the assumption that human beings also show this behaviour in their choice of vocation, we hypothesise that young people are more likely to expect negative reactions from their social environment when choosing a gender-atypical occupation. Furthermore, we assume that the expected reaction of the social environment influences vocational orientation: The anticipation of negative reactions to gender-atypical vocational choice might contribute to explain why young people ignore this occupation. We tested both hypotheses with the help of data retrieved from a survey of young people in Germany who are interested in vocational education and training (VET). The results support our hypotheses; however, they also show that the relevance of a gender-typed vocational choice is weaker if adolescents have a higher educational background. In this case, the choice of an occupation that expresses a high educational status becomes more important. It may lead to an exclusive kind of social approval that is denied to people with a lower educational background.

When the media report negatively about an organisation, its employees are not only affected but also a source of information for outsiders who want to find out more about the situation. Because of their credibility, employees can support public relations managers to preserve or restore organisational reputation. In this research, we explore the role of organisational identification and internal corporate communication (ICC) in the event of negative media coverage for employees’ defensive and assertive impression management behaviours. Defensive strategies include excuses, justifications and the avoidance of threatening situations. Assertive strategies are more active and refer to behaviours which aim to establish a desirable identity; in the context of negative media coverage, this entails actively defending the organisation, explaining the situation and conveying the organisation’s official version of the event in order to bolster its reputation. Results from an online survey among employed persons reveal that employees’ identification with their work organisation positively influences their assertive as well as defensive reactions. ICC has a more differentiated influence on employees’ reactions: If ICC is evaluated well, employees’ assertive reactions increase; if evaluated poorly, employees exhibit more defensive reactions. These findings show that ICC can make a difference in winning employees as ambassadors for the organisation in critical situations.

Purpose – This study examines both the short- and long-term share price reaction to announcements of financial restatements cited in the U.S. General Accounting Office (2006) database.

Methodology – It uses the augmented four-factor Fama-French model for assessing share price reaction.

Findings – The study finds that the average cumulative abnormal return (CAR) for a sample of 553 restatements (by 437 companies) is significantly negative (−1.58) for the three-day window surrounding the day of announcement. The average CAR for the one-year period prior to the announcement (−9.6%) and for each of the four years after the announcement is negative as well, with the average CAR for the four years adding up to −22%. The study also documents differences in CARs based on the entity prompting the restatement (company, auditor, and Securities and Exchange Commission), the reason behind the restatement (revenue, cost, reclassification of item, etc.), and for one-time versus repeat offenders.

Social implications – Taken together, the findings indicate that financial restatements impose significant short-term as well as long-term costs on shareholders.

Originality/Value – The evidence about long-term share price reaction to financial restatements is missing in prior research. The relationship between long-term and short-term share price reaction to financial restatements fails to suggest systematic over/underreaction by the market.

We examine the stock market reaction to the Tax Cuts and Jobs Act (TCJA) of 2017 during its enactment process, focusing on its international provisions. Consistent with extant evidence, we find lower returns for high-foreign-activity firms, indicating a negative market reaction to the international provisions overall. Considering specific international provisions, we find that the market reaction was more positive (negative) for firms likely most affected by the shift to a quasi-territorial system for taxing foreign earnings (the transition tax on existing unrepatriated earnings, the tax on global intangible low-taxed income, and/or the base erosion and antiabuse tax) than for other firms. Our findings imply that investors are able to disentangle the economic implications of complex and interactive tax law changes.

Misconduct allegations have been found to not only affect the alleged firm but also other, unalleged firms in form of reputational and financial spillover effects. It has remained unexplored, however, how the number of prior allegations against other firms matters for an individual firm currently facing an allegation. Building on behavioral decision theory, we argue that the relationship between allegation prevalence among other firms and investor reaction to a focal allegation is inverted U-shaped. The inverted U-shaped effect is theorized to emerge from the combination of two effects: In the absence of prior allegations against other firms, investors fail to anticipate the focal allegation, and hence react particularly negatively (“anticipation effect”). In the case of many prior allegations against other firms, investors also react particularly negatively because investors perceive the focal allegation as more warranted (“evaluation effect”). The multi-industry, empirical analysis of 8,802 misconduct allegations against US firms between 2007 and 2017 provides support for our predicted, inverted U-shaped effect. Our study complements recent misconduct research on spillover effects by highlighting that not only a current allegation against an individual firm can “contaminate” other, unalleged firms but that also prior allegations against other firms can “contaminate” investor reaction to a focal allegation against an individual firm.