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Background: A large amount of phosphogypsum occupies the land and causes the environmental pollution. It is of great research significance and urgency to utilization of the phosphogypsum. Methods: The influence of the ratio of the cementing materials and phosphogypsum (C/P ratio) on the compressive strength, water absorption, softening coefficient and freeze-thaw stability of the phosphogypsum baking-free bricks was investigated. The consolidation process of the phosphogypsum baking-free bricks was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results: XRD patterns show that the phosphogypsum baking-free bricks curved for 28 d are mainly composed of monoclinic CaSO4•2H2O and hexagonal Ca6Al2(SO4)3(OH)12•26H2O (Aft) phases. SEM observation shows that the phosphogypsum bricks consist of Aft nanorods and irregular microscale particles. The softening coefficient, water-resistant performance and freeze-thaw stability of the phosphogypsum baking-free bricks remarkably decrease with decreasing the C/P ratio. 28 d compressive strength decreases from 26.42 MPa to 15.58 MPa with the change of the C/P ratio from 1:1 to 1:2.5. The optimal ratio of the cementing materials and phosphogymsum is 1:1. The phosphogypsum baking-free bricks exhibit good stability after 18 freeze-thaw cycles. Conclusion: Phosphogypsum baking-free bricks were prepared by natural curing process using phosphogypsum as the raw materials, cement, slag, fly ash and silica fume as the cementing materials. The phosphogypsum baking-free bricks exhibit great application in the field of the building materials.

Although stereotype has its own defects, it is indispensable in cross-cultural communication. Based on the analysis of the necessity of stereotype in cross-cultural communication, this paper points out that the inherent defects and the logical fallacy of stereotype are the important factors that cause the failure of cross-cultural communication. And communicators should take into account the relavance between stereotype and individual cross-cultural communication behaviors in the process of cross-cultural communication. On the basis of stereotype, cross-cultural communicators should have a good understanding of foreign cultures to make cross-cultural communication effective.

Background: Binge drinking is a dangerous practice. Among college students, continuously high rates of binge drinking on campus result in deaths, accidents, poor academic performance, risky behavior, the development of substance use disorder, and a number of other serious problems and conditions. Collegiate Recovery Programs have shown promise as an intervention for curbing binge drinking at colleges and universities. Objective: This paper reviews the literature on the prevalence and risks of campus binge drinking, and the relative success of interventions designed to limit it. While certain initiatives have succeeded more than others, the most appropriate strategy combines efforts on the environmental and individual level to incorporate policies tailored to the unique needs of a given collegiate community, consistent with findings on the best options for treatment and recovery in general. Result: : Evidence suggests that Collegiate Recovery Programs are an effective strategy at some schools because they provide holistic and targeted care for students in recovery. They serve a vulnerable student population whose interests are often overlooked in the wider consideration of campus binge drinking and issues of safety and bureaucratic incentives. Conclusion: Collegiate Recovery Programs ought to be considered as at least one helpful avenue for schools considering mechanisms to cut down on elevated binge drinking rates. Tailored strategies mixing other effective approaches should consider these programs as part of their overall focus.

Aims: The aim is to prepare baking-free bricks using iron ore tailings as the main raw materials. Objective: Iron ore tailings have increased dramatically in recent decades. The storage of the iron ore tailings has potential environmental and safety hazard. Therefore, it is urgent to use the tailings to produce valuable products. Objective: The objective of the research is to treat the tailings by preparing the baking-free bricks. Method: The phases and micro-morphology of the baking-free bricks have been investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The optimal components and preparation parameters of the baking-free bricks were determined by controlling the ratio of the raw materials and forming pressure. The physical properties of the baking-free bricks including compressive strength and density have been analyzed by controlling the forming pressure and curing time. Result: The optimal components of the baking-free bricks is 65wt.% tailings, 5wt.% titanium gypsum, 17wt.% slag, 5wt. Conclusion: Baking-free bricks have been successfully prepared from the iron ore tailings adding a small amount of cementing materials including titanium gypsum, slag, acetylene sludge and waste brick powder. Other: The XRD pattern and SEM observation show that 28 d tailing bricks are mainly composed of irregular particles and a large number of ettringite (Aft) nanorods. The analyzed results revealed that the formed irregular particles and Aft nanorods contribute to the improvement of compressive strength and compactness of the tailing bricks.