High-/medium-entropy alloys (H/MEA) have the inherent local chemical order. Yet, as a structural link between the incipient short-range order and mature long-range counterpart, the chemical medium-range order (CMRO) is conjectural and remains open questions as to if, and what kind of, CMRO would be produced and if CMRO is mechanically stable during plastic deformation. Here, we show compelling evidences for CMRO in an Al9.5CrCoNi MEA. Specifically, the electron diffraction under both [$$112$$ 112 ] and [$$013$$ 013 ] zone axis show the definite spots for CMRO of lattice periodicity. CMRO entities are seen directly of medium-ranged in sizes by using dark-field imaging, along with the tendency towards like-pair avoidance and unlike-pair preference based on atomic-resolution EDS mapping. These findings substantiate CMRO with a realistic structural picture in view of crystal periodicity and chemical species occupation, shedding light on understanding the microstructural link at an extended length scale beyond the short-range order.

In recent years, the chemical companies in different countries have realized the significance of managing within safety regulations and rules. In China, investigation reports of major accidents showed that Chinese chemical companies often failed to comply with regulations before the accident. In fact, a majority of chemical companies are simultaneously regulated by different regulatory agencies. They must comply with an excess of safety regulations and standards promulgated by various regulatory agencies. A huge compliance burden for chemical companies is the result. To solve this problem, this article proposes a new classification method combining administrative ranks and scopes of chemical safety activities. This new classification helps chemical companies to identify and understand external regulations faster and more easily. A chemical industry park in Dalian was taken as an example to collect materials. It was found that there were 658 regulations and standards covering safety, environment and health. In addition, this article establishes a procedural framework for rules management that guides users of rules, which demonstrates the process of compliance management. It helps companies deal with situations where external regulations are absent or unreasonable. This article also suggests that regulators establish good communication with companies and increase the discretionary power of companies to promote the implementation of this framework.

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