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As the global oil market continues to tighten, there is an increasing focus on enhancing oil recovery. However, enhanced oil recovery technologies require the addition of chemical components such as surfactants, alkalis, and polymers to the oil reservoir. These chemical components change the interface structure and affect fluid flow characteristics and phase interactions through adsorption and other behaviors, thus affecting the production efficiency and energy consumption of oil recovery, gathering, processing, and transportation. Particularly, a stable interface is formed during oil recovery that can sharply increase the difficulty of phase separation during oil gathering and processing, thereby considerably decreasing the separation efficiency. Therefore, it is crucial to understand the effect of the interface structure and behavior on fluid flow characteristics and phase interactions for the advancement of the petroleum industry. Herein, the application and regulation of interfaces in the petroleum industry for fluid flow characteristics and phase interactions are reviewed, approaches for characterizing interface characteristics are critically analyzed and discussed, mechanisms of various factors influencing interface formation and stability through phase interactions are investigated, and methods of interface inhibition and destruction are summarized. Moreover, the latest techniques for applied interface formation in the petroleum industry are discussed, and the challenges and research prospects related to interfaces are summarized, providing references for enriching theoretical research in the field of interfaces within the petroleum industry and efficiently optimizing the production and operation of the petroleum industry.

We select a small set of recommendations that lie in the upper and lower tail of the empirical distribution of divergences between a recommendation, and the consensus over the window (−30, −1) days prior to that recommendation. We classify these extremely divergent recommendations as bold, and then subdivide them into informative bold recommendations that lead other analysts (leading‐bold) and those that are ignored by other analysts (contra‐bold) based on the consensus change in the 30 days after the announcement. We focus on the information conveyed to the market by these bold, leading‐bold, and contra‐bold recommendations through their effects on cumulative abnormal returns (CAR). We find that bold recommendations are not anticipated by market participants (CARs are negative before a bold buy and positive before a bold sell). The next finding is that the market responds strongly to both leading and contra‐bold recommendations over the (0, +4)‐day window and that these reactions are stronger than that to nonbold recommendations. In contrast, over the longer (0, +30)‐day window, leading‐bold recommendations earn additional returns whereas contra‐bold ones reverse significantly due to lack of confirmation. The overall pattern is one of rational market reaction both in the short and long windows. We support the rationality of the market reaction by showing that the percentage of leading‐bold recommendations exceeds that of contra‐bold recommendations, and that these two types of recommendations cannot be separated using observable analyst characteristics such as experience or brokerage size.

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