The emission behavior of a new V-shaped organic fluorescent compound (p,p′-bis(2-aryl-1,3,4-oxadiazol-5-yl)diphenyl sulfone (OZA-SO)), consisting of diethylamino (donor) and sulfone (acceptor) units, has been studied in various polar solvents and with different morphologies. As expected, there is the gradual transition from the locally excited state to the intramolecular charge-transfer (ICT) state with the increasing solvent polarity. The photoluminescence intensity of OZA-SO initially decreases with a low water fraction (f(w)), owing to ICT effect, and then increases with a high f(w), owing to crystallization-induced emission enhancement. At the same time, the fluorescence lifetime of OZA-SO increases from 0.062 ns in dimethylformamide (DMF) to 5.80 ns in a solution containing 90 % water, and then to 7.49 ns in a solution containing 60 % water. Furthermore, the solid-state emission of OZA-SO can be tuned reversibly from green to yellow by fuming/grinding or fuming/heating owing to morphological changes. This color-switchable feature of OZA-SO may have potential applications in optical-recording and temperature-sensing materials.

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A new type of rhombic grid hyperboloid-latticed shell (RGHLS) being investigated in this study is only formed by major and secondary inclined columns without any circumferential hoop members. This intends to achieve more transparency for architectural effect by neglecting its circumferential hoop members and lateral braces in radial direction of the RGHLS, and meanwhile, the RGHLS is expected to experience a significant strength reduction. This paper numerically investigates the load resistance and hysteretic response of such RGHLS subjected to combined vertical and horizontal loads by adopting finite element method, where multicolumn interaction instability failure mechanism and load-carrying capacity of the RGHLS are being focused on. It was found that the RGHLS failed by multicolumn interactive instability between the major and secondary columns, with associated in-plane and out-of-plane flexural deformations of the columns. The overall interactive load-carrying capacity design curve N/Nu-M/Mu of the RGHLS was proposed based on numerous finite element results. The results indicate that the strength design of the RGHLS with a door opening being adopted in the practical engineering application is reliable and rational with a certain amount of safety margin. At last, hysteretic response of the RGHLS is investigated according to the loading protocol specified in AISC341-05. KEYWORDS elastic buckling behavior, FE numerical investigation, hysteretic response, interactive design curve, load-carrying capacity, rhombic grid hyperboloid-latticed shell (RGHLS) with and without a door opening

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