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The purpose of this study is to investigate the performance of eight perylene diimide pigments as a hypothetical building facades using EnergyPlus.

A hypothetical building located in Tehran is modeled using EnergyPlus, and the effectiveness of the pigments was examined. Furthermore, the performance of the pigments was compared with those of common commercial black (carbon black) and red (iron oxide) pigments.

The results show that the studied black pigments reduce the cooling energy demand up to 37 per cent in comparison with carbon black paint and the red ones, which reduce the value by as much as 32 per cent in comparison to iron oxide.

This study demonstrates that the application of cool paints rather than common paints will significantly reduce the cooling energy demand and subsequent costs.

Self-organization has been regarded as a tool for the synthesis of well-defined organic nanostructures. Heterocyclic annulated perylene diimides are the subjects of considerable current research studies. The purpose of this study is to reveal the photophysical property, electronic structure and solid-state packing of O-heterocyclic annulated perylene diimide.

Asymmetrically five-membered O-heterocyclic annulated perylene diimide (OAPDI) was synthesized. Structure and purity of OAPDI were confirmed by ¹H NMR, ¹³C NMR, IR and mass spectral techniques. Photophysical properties of OAPDI were studied using UV–vis absorption and fluorescence in both solution (CHCl₃) and solid state. Scanning electron microscopic and atomic force microscopy were used to characterize the surface morphology of OAPDI. Conducting properties of the OAPDI were evaluated by current–voltage measurements. The compounds geometries were also optimized at 6-31G* using density functional theory.

The UV–vis absorption and fluorescence spectra of OAPDI in solution are blue-shifted in comparison with that of unsubstituted perylene bisimide. Solid-state UV–vis measurements of OAPDI indicate that it is capable of forming highly ordered structure. The non-covalent interactions, electrostatic attraction and p-p stacking moieties of OAPDI synergistically guide assembly and domain growth while maintaining the interpenetrating network of nanofibers in the solid film. The OAPDI gave higher current at −2.0 V (0.68 µA) and 4.0 V (1.0 µA).

This study will be helpful for exploring feasible routes to acquire soluble perylene diimides and well-defined organic nanostructures. Furthermore, such molecular tailoring approach would be helpful for designing and synthesizing novel organic semiconductive materials with excellent charge-transporting and light-emitting capabilities.

This paper aims to focus on the most popular technique nowadays, the use of microwave irradiation in organic synthesis; in a few years, most chemists will use microwave energy to heat chemical reactions on a laboratory scale. Also, many scientists use microwave technology in the industry. They have turned to microwave synthesis as a frontline methodology for their projects. Microwave and microwave-assisted organic synthesis (MAOS) has emerged as a new “lead” in organic synthesis.

Using microwave radiation for synthesis and design of fluorescent dyes is of great interest, as it decreases the time required for synthesis and the synthesized dyes can be applied to industrial scale.

The technique offers many advantages, as it is simple, clean, fast, efficient and economical for the synthesis of a large number of organic compounds. These advantages encourage many chemists to switch from the traditional heating method to microwave-assisted chemistry.

This review highlights applications of microwave chemistry in organic synthesis for fluorescent dyes. Fluorescents are a fairly new and very heavily used class of organics. These materials have many applications, as a penetrant liquid for crack detection, synthetic resins, plastics, printing inks, non-destructive testing and sports ball dyeing.

The aim value of this review is to define the scope and limitation of microwave synthesis procedures for the synthesis of novel fluorescent dyes via a simple and economic way.