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In this paper, the HAZOP‐LOPA‐SIL method is implemented on a safety assessment for an O‐benzenedicarboxylic acid diallyl ester (DPA) demulsifier production process. The risk matrix and tolerable risk criterion are determined with hazard and operability (HAZOP) analysis, and the whole processing technique is divided into nine nodes and seven safety instrumented functions (SIFS). By using guide words and subsequence parameters, the deviation of each node is analyzed, and recommendations are then proposed. After determining the safety integrity level (SIL) of each SIF according to the layer of protection analysis (LOPA) method, the result shows that the SIL of the whole system is SIL1. Considering the influence of mechanical element degradation (valves) on SIL determination, gamma distribution has been adopted to analyze the gradation process. In the serviceable cycle, the minimum PFD average is larger than 0.21 in order to exceed the range of SIL 1. This means that the SIL of the SIF can effectively prevent the failure caused by valve degradation. According to software analysis, the SIL validation result of the whole safety instrument system(SIS) is SIL1. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a novel simple method is presented to synthesize highly pure Ti3AlC2 powder by heating 2TiC/Ti/Al (molar ratio) powder system between 1300°C and 1400°C for 15–30min in flowing argon atmosphere. 2TiC/Ti/Al is selected as the raw material because of its much lower exothermal quantity than elemental 3Ti/Al/2C powder system in reacting process. The purity of Ti3AlC2 is not sensitive to the final temperature, soaking time or raw material scale. Its content is maintained around 97wt.%, even though the scale of mixed raw materials vary from 5g to 1000g. The synthesized samples can be easily ground into powders with a mean particle size of 4.9μm. Synthesis mechanism shows that both Ti2AlC and Ti3AlC2 will generate from the reaction among TiC, Ti and Al below 1200°C. Above 1300°C, Ti2AlC will continue to react with TiC and generate Ti3AlC2. The formation of Al liquid phase above 660°C is considered as a promoting factor in the reacting process. [Copyright &y& Elsevier]

Introduction: A family history of psychiatric disorders is one of the strongest risk factors for schizophrenia. The characteristics of patients with a family history of psychiatric disorders have not been systematically evaluated., Methods: This multicenter study (26 centers, 2425 cases) was performed in a Chinese population to examine the sociodemographic and clinical characteristics of schizophrenia patients with a family history of psychotic disorders in comparison with those of patients with sporadic schizophrenia., Results: Nineteen percent of patients had a family history of mental disease. Multiple logistic regression analysis revealed that ≥4 hospitalizations (OR = 1.78, P = .004), tobacco dependence (OR = 1.48, P = .006), alcohol dependence (OR = 1.74, P = .013), and physical illness (OR = 1.89, P = .001) were independently and significantly associated with a family history of mental disease., Conclusion: Patients with a family history of mental disorders present different demographics and clinical features than patients without a family history of psychiatric disorders., (© 2020 John Wiley & Sons Australia, Ltd.)

In this Article, we investigate the effect of a precursor layer, which is composed of four bilayers of polyethyleneimine (PEI) and poly(sodium styrene sulfonate) (PSS), on the subsequent LBL assembly of hybrid films composed of indium tin oxide (ITO) nanoparticles and PSS. A precursor polyelectrolyte layer is usually deposited to minimize interference by the substrate. It is shown here that the "effective" surface charge of the precursor layer can significantly affect the subsequent assembly behavior of [ITO/PSS](9.5) hybrid thin films. Depending on the surface charge of the precursor layer, the subsequent LbL assembly of [ITO/PSS](9.5) hybrid films can exhibit either one or two regimes. When two growth regimes are present, the first one consists of a "recovery regime", and the second is the expected "linear growth regime." The length of the "recovery regime" is dependent on how much positive charge the precursor layer possesses and how fast this surface charge can be compensated. This work reveals for the first time that changes in the surface charge of the precursor layer can have a significant effect on the subsequent LBL assembly process. The surface charge of the precursor layer was investigated using ζ-potential measurements on model silica microspheres. These experiments showed that the surface charge of the precursor layer, [PEI/PSS](4), is dependent on the pH of the solution in which it is immersed, and that it can reverse from a negatively charged surface to a positively charged one, at sufficiently low pH due to the protonation of PEI, despite having the negatively charged PSS layer as the outermost layer.