RESUMO
Single-component semiconductors with photoresponse to full solar spectrum are highly desirable to simplify the device structure of commercial photodetectors and to improve solar conversion or photocatalytic efficiency but remain scarce. This work reports bottom-up photosynthesis of an air-stable radical semiconductor using BiI3 and a photochromism-active benzidine derivative as a photosensitive functional motif. This semiconductor shows photoconductivity to full solar spectrum contributed by radical and non-radical forms of the benzidine derivative. It has also the potential to detect X-rays because of strong X-ray absorption coefficient. This finding opens up a new synthetic method for radical semiconductors and may find applications on extending photoresponsive ranges of perovskites, transition metal sulfides, and other materials.
RESUMO
The design and synthesis of energetic materials (EMs) with high energy and reliable stabilities has attracted much attention in the field of EMs. In this work, we employed a strategy of the coordination polymerization of mild dicyanamide ions (DCA-), two isomeric ligands 1-methyl-5-aminotetrazole (1-MAT) and 2-methyl-5-aminotetrazole (2-MAT) to construct energetic coordination polymers (ECPs). Four new ECPs {[Co(DCA)2(1-MAT)2]·H2O}n1, [Cu(DCA)2(1-MAT)]n2, [Cd(DCA)2(1-MAT)2]n3 and [Cd(DCA)2(2-MAT)2]n4 were successfully synthesized through solvent evaporation routes. Compounds 1 and 4 display 1D chains, while 2 and 3 exhibit 2D-layered structures. Compounds 1-3 with the 1-MAT ligand all exhibit reliable thermal stabilities (> 200 °C). The calculated heats of detonation (ΔHdet) of 1-3 are all higher than 1.4 kJ g-1, which are higher than traditional explosive TNT (1.22 kJ g-1) and the reported ECP AgMtta (HMtta = 5-methyl-1H-tetrazole, ΔHdet = 1.32 kJ g-1). Furthermore, sensitivity testing demonstrates that 1-4 features low mechanical sensitivity to external mechanical action in contrast with the extremely sensitive azide-based ECPs [Cu3(2-MAT)2(N3)6]n. In addition, compound 2 shows hypergolic properties via an 'oxidizer-fuel' drop experiment, demonstrating its application prospects in the field of propellants. This work details an approach of synthesizing multipurpose ECPs with reliable stabilities by introducing mild dicyanamide anions into nitrogen-rich skeletons.
RESUMO
@#Night-wear aspheric orthokeratology lens(refers to OK lens)is used to correct vision while sleeping at night, which is one of the few ways to prevent myopic children from wearing glasses during the day, so often recommended as the first choice in clinical practice for the myopic population of 8-16 years old. The main effect of OK lens is producing reasonable compression on the surface of the eye to reduce the curvature of the cornea. At present, as a recognized non-surgical method for the treatment of juvenile myopia, the lens material and the optometry level of OK lens have been continuously innovated and upgraded. Meanwhile,because OK lens directly cover the ocular surface, so long-term wearing definitely affects the ocular surface microenvironment, including meibomian glands, tear film, conjunctiva, cornea, ocular surface microorganisms and so on, and even causes the imbalance of these ocular surface microenvironments, thereby leading to the occurrence and development of ocular surface diseases. In order to expect clinicians to give comprehensive consideration when wearing OK lens for teenagers and increase the safety and effectiveness of wearing OK lens, this article analyzed the effects of wearing OK lens on ocular surface meibomian gland morphology, tear film morphology and function, conjunctival microcirculation, corneal cell morphology, ocular surface microorganisms and other factors.