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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 compare the electronic properties of perylene diimide derivatives (DFPDI) and its anion radical (DFPDI.^-k.⁺) thin film by drop-coating of organic molecules on the interdigitated electrodes.

The authors compared the electronic properties of perylene diimide derivatives and its anion radical by drop-coating of organic molecules on interdigitated electrodes. Significantly, the current of perylene diimide derivatives anion radical increased by 2∼3 orders of magnitude compared to perylene diimide derivatives under a bias of 5 V, and the maximal current of anion radical that from tetrahydrofuran solution can reach 3.6 mA. Furthermore, DFPDI.^-k.⁺ thin film showed time-resistance sensitivity for acetic acid. When DFPDI.^-k.⁺ thin film was placed in acetic acid of 3.1 × 105 ppm, the current was decreased 46 times under a bias of 6 V after 8 min.

We developed the new method to prepare ambient stable perylene diimide derivatives anion radical, which shows sensitivity of absorption spectra to acid.

Perylene diimide derivatives anion radical thin film showed time-resistance sensitivity for acetic acid, suggesting potential application of perylene diimide derivatives anion radical as acid sensor.

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.

A novel semiconducting macromolecule-polyperylene tetraamide (PPTI) was first synthesized with a simple method using 3, 4, 9, 10-perylene tetracarboxylic acid (PTCA) and hydrazine hydrate (N2H4).

The Ag nanoparticle was doped on the surface or inside of the PPTI film to obtain a highly sensitive hydrazine sensor-Ag/PPTI, which was synthesized within one step. The structure of Ag/PPTI was characterized through various techniques such as Fourier transform infrared (FT-IR), thermogravimetric analyzer (TGA), X-ray diffraction (XRD), X-ray photoelectron spectroscopy measurements (XPS) and scanning electronic microscopy (SEM).

According to cyclic voltammetry results, Ag/PPTI/GCE indicated good electrocatalytic activity toward the oxidation of hydrazine. The amperometric detection of hydrazine was then applied on Ag/PPTI/GCE. It exhibited a wide linear range from 0.05 to 50 µM, a low detection limit (S/N = 3) of 0.05 µM and high sensitivity of 0.45 µA/(µM•cm2).

In authors’ perception, this approach emerges as an effective technique for developing efficient chemical sensors for environmental pollutants.

BASF has supplemented the group of perylene pigments in their Paliogen range with Paliogen Maroon L 3820.

Paliogen Black L 0084 is a perylene pigment that can reflect infra‐red radiation and is being launched on the market by BASF. At about 650 nm, the slope of the infra‐red reflection curve for Paliogen Black L 0084 commences to rise steeply. This property is of great significance for camouflage paints, and the pigment's green undertone in the visible range is in line with this application. Paliogen Black L 0084 is suitable for outdoor applications.

To evaluate the photoelectrochemical characteristics of polymer doped with CdSe and CdSe/TiO₂ for improved photoelectric conversion efficiency.

A method was set‐up to dope the nano‐CdSe with poly‐perylene‐tetracarboxylic imide (PPI) in the nano‐TiO₂/ITO films, which were characterised by X‐ray diffraction; electrochemical analytical system; multifunctional grating spectrometer; digital photometer and ultrasonic cleanout instrument, etc.

The modification of PPI doped with CdSe and CdSe/TiO₂ showed significant elevation of the monochromatic incident photo‐to‐electron conversion efficiency (IPCE) of the photoelectrode, which was about 3 per cent. The doping caused a tone up separate efficiency of charge, restraining the complex of electron‐cavity by doped nano‐CdSe. Therefore, the photocurrent of the TiO₂ film doped with nano‐CdSe was about three times higher than that without.

The mixed film could also be formed from conjugated polymer mixed with polymer and inorganic particle, based on polymer doped with CdSe and CdSe/TiO₂. In addition, the monochromatic incident IPCE of the photoelectrode needs to be extensively studied.

The treatment method developed provided a practical and effective solution to increasing the ICPE.

The method for doping polymer with CdSe and CdSe/TiO₂ was novel and could probably be adapted for the manufacture of solar cell.

3.2.5 Proportion of functional groups in the binder From fig. 14 we can see how the proportion of carboxyl groups in an acrylate resin at otherwise constant conditions can influence the rub‐out effect in two different polar coloured pigments.

This study aims to assess and compare the quality and safety of street-vended, ready-to-eat fried and smoked West African Ilisha fish from the major markets in Ibadan, Oyo State, Nigeria.

A total of 50 samples each were obtained from ten major markets in Ibadan, Oyo State, Nigeria. Samples were analyzed in the laboratory for proximate, rancidity indices; i.e. peroxide value (PV), thiobarbituric acid (TBA), total volatile base-nitrogen (TVB-N), trimethylamine acid (TMA) and free fatty acid (FFA), polycyclic aromatic hydrocarbon (PAH) and heavy metals.

The results showed that the mean PV (meq. peroxide/kg), TBA (mg Mol/kg), TVB-N (mgN/kg), TMA (mgN/kg) and FFA (%) contents within the fried fish samples ranged from 18.86-23.11, 2.08-2.98, 14.89-17.79, 1.98-2.89 and 2.46-5.98, respectively, while in the case of smoked fish samples, the corresponding contents were found to be 9.03-15.96, 1.03-1.59, 17.29-19.36, 2.15-2.68 and 1.13-1.62, respectively. The results also revealed the presence of PAH compounds in the fried and smoked fish samples. However, majority of the PAH compounds were above 5.0 μg/kg B(a)P maximum permissible levels set by EU Regulation 1881/2006. Concentrations of Hg, Pb, Cd and Cr in the fried and smoked fish samples showed that quantities of these trace heavy metals were below the recommended limits set by the World Health Organization and hence posed no risk to the consumers. The study concluded that consumption of fried and smoked fish may expose consumers to high-level PAH.

The fried and smoked West African Ilisha fish samples used in this study were obtained from major markets in Ibadan, Oyo State, and there were limitations in getting the same samples with the same treatments in time because of poor and non-established uniform methodology of frying and smoking.

The paper helps in measuring quality and safety standards of fried and smoked fish products to reduce the incidence of food poison and enhance the health of consumers.

This research is of value to the traditional fish processors, government agencies responsible for food quality control and assurance as well as consumers, as little work has been done on this product.