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Photocatalysts have been effectively applied for water treatment. Narrow bandgap energy semiconductors show good photocatalytic performance at visible light. However, high recombination rate of the photogenerated electrons and holes leads to their low photocatalytic activity. Moreover, the conduction and valence band potentials of these materials are not suitable for the redox reactions with water and oxygen to generate HO• and •O2⁻ radicals, respectively. Therefore, the development of new photocatalyst systems to overcome these disadvantages is necessary. This study investigated the photocatalytic activity of FeWO4/rGO/g-C3N4 Z-scheme photocatalytic system via the degradation of Rhodamine B in water. The photocatalyst was synthesized by simple hydrothermal method and characterized by X-ray diffraction method (XRD), fluorescence spectroscopy (PL) and diffuse reflectance spectra (UV-vis). The results showed that after 150 minutes illumination, the Rhodamine B decomposition efficiency on FeWO4/g-C3N4 and FeWO4/rGO/g-C3N4 were 93.07 and 99.21%, respectively. These values were significantly higher than that of g-C3N4 under the same catalytic concentration of 0.1g/L. In the FeWO4/rGO/g-C3N4 heterostructure, rGO acted as electron mediator and transporter between two semiconductors, resulting in a lower recombination rate of photogenerated charges. As the results, the photocatalytic performance was enhanced.

Freezing techniques are an essential part of biologics manufacturing processes, yet the formation of ice/water interfaces can impart detrimental effects on proteins. However, the absence of chemical and structural differences between ice and liquid water poses the question as to why ice can destabilize proteins. We hypothesize that the destabilizing stress of the ice-liquid water interface does not originate from the ice-water system itself but rather from the air microbubbles present during the freezing process. As the temperature decreases, the dissolved air is expelled from the ice crystal lattices in the form of microbubbles and is subsequently trapped by the advancing ice front. This newly formed air-water interface represents an additional interfacial area for the proteins to be adsorbed onto and denatured. The result showed that freezing at ∼ 1 K/s led to the formation of small circular microbubbles with diameters ranging from 100 µm to 500 µm. In contrast, slower freezing resulted in the formation of larger, elongated millimeter-size bubbles. The reduction of the number of microbubbles was carried out by the deaeration process using agitation under reduced pressure at 20 kPa. The resulting deaerated (i.e., low dissolved air) protein samples were frozen and monitored for the formation of subvisible aggregates using micro-flow imaging (MFI). The results demonstrated that deaerating the samples prior to intermediate freezing (i.e., TFF) reduced the number of aggregates for both highly surface-active and low surface-active proteins (lactoferrin and bovine IgG, respectively). This reduction was more pronounced in spray freeze drying (SFD) than thin-film freezing (TFF), and less apparent in conventional lyophilization.

A series of new ethynylated benzoindoles were synthesized starting with the nucleophilic attack of naphthoquinone by lithium acetylides. The resulting 1,4-diethynylnaphthalenes were applied in palladium catalyzed CN coupling - hydroamination domino reactions. The obtained compounds fluoresce in the near ultraviolet and blue spectral region with high quantum yields (65–78%).

A palladium-catalyzed one-pot reaction for the synthesis of benzo[b]carbazolediones is described which proceeds by amination of 2,3-dibromonaphthoquinone, Suzuki cross-coupling with (2-bromo­phenyl)boronic acid, and subsequent intramolecular C–N Buchwald–Hartwig cyclization with amines.

A palladium-catalyzed one-pot reaction for the synthesis of benzo[b]carbazolediones is described which proceeds by amination of 2,3-dibromonaphthoquinone, Suzuki cross-coupling with (2-bromo­phenyl)boronic acid, and subsequent intramolecular C–N Buchwald–Hartwig cyclization with amines.