Constructing N-Containing Poly(p-Phenylene) (PPP) Films Through A Cathodic-Dehalogenation Polymerization Method.

Developing the films of N-containing unsubstituted poly(p-phenylene) (PPP) films for diverse applications is significant and highly desirable because the replacement of sp2 C atoms with sp2 N atoms will bring novel properties to the as-prepared polymers. In this research, an electrochemical-dehalogenation polymerization strategy is employed to construct two N-containing PPP films under constant potentials, where 2,5-diiodopyridine (DIPy) and 2,5-dibromopyrazine (DBPz) are used as starting agents. The corresponding polymers are named CityU-23 (for polypyridine) and CityU-24 (for polypyrazine). Moreover, it is found that both polymers can form films in situ on different conductive substrates (i.e., silicon, gold, ITO, and nickel), satisfying potential device fabrication. Furthermore, the as-obtained thin films of CityU-23 and CityU-24 exhibit good performance of alkaline hydrogen evolution reaction with the overpotential of 212.8 and 180.7 mV and the Tafel slope of 157.0 and 122.4 mV dec-1, respectively.

A Metal-Free Helical Covalent Inorganic Polymer: Preparation, Crystal Structure and Optical Properties.

Helical morphologies are widely observed in nature, however, it is very challenging to prepare artificial helical polymers. Especially, precisely understanding the structure information of artificial metal-free helical covalent inorganic polymers via single-crystal X-ray diffraction (SCXRD) analysis is rarely explored. Here, we successfully prepare a novel metal-free helical covalent inorganic polymer ({[Te(C6 H5 )2 ] [PO3 (OH)]}n , named CityU-10) by introducing angular anions (HOPO3 2- ) into traditional tellurium-oxygen chains. The dynamic reversibility of the reaction is realized through the introduction of organic tellurium precursor and the slow hydrolysis of polyphosphoric acid. High-quality and large-size single crystals of CityU-10 have been successfully characterized via SCXRD, where the same-handed helical inorganic polymer chains form a pseudo-two-dimensional layer via multiple hydrogen-bonding interactions. The left-handed layers and right-handed layers alternatively stack together through weak hydrogen bonds to form a three-dimensional supramolecular structure. The single crystals of CityU-10 are found to display promising optical properties with a large birefringence. Our results would offer new guidelines for designing and preparing new crystalline covalent polymers through tellurium-based chemistry.

Cystic lymphangioma of adrenal gland: a clinicopathological study of 3 cases and review of literature.

Cystic lymphangioma of the adrenal gland is a rare and benign lesion, most often found incidentally during abdominal imaging studies, abdominal surgery or at autopsy. We aimed to retrospectively review all adrenal lymphangioma cases at our hospital, further document their lymphatic origin by immunohistochemical staining and discuss the differential diagnosis with other cystic adrenal gland lesions. A total of 3 adrenal lymphangioma cases were identified. All three patients were men and adults at time of diagnosis aged 41 years, 43 years, and 66 years, respectively. All were incidentally identified during investigating for unrelated reasons, two of which were discovered by routine radiologic check-up while the last one was found during imaging detection of ureteral cancer. The average size of an adrenal lymphangioma lesion was 3.2 cm (range, 2.5-4.6 cm). Histologically, all three cases showed a typical multicystic architecture with dilated spaces lined by flattened, bland, simple lining. The cystic spaces occasionally contained proteinaceous material but lacked red blood cell content. On immunohistochemical stains, D2-40 cytoplasmic staining was positive in all three lesions, whereas AE1/AE3 was negative, thus, confirming their lymphatic nature.