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The properties of catenated nitrogen molecules, molecules containing internal chains of bonded nitrogen atoms, is of fundamental scientific interest in chemical structure and bonding, as nitrogen is uniquely situated in the periodic table to form kinetically stable compounds often with chemically stable N-N bonds but which are thermodynamically unstable in that the formation of stable multiply bonded N2 is usually thermodynamically preferable. This unique placement in the periodic table makes catenated nitrogen compounds of interest for development of high-energy-density materials, including explosives for defense and construction purposes, as well as propellants for missile propulsion and for space exploration. This review, designed for a chemical audience, describes foundational subjects, methods, and metrics relevant to the energetic materials community and provides an overview of important classes of catenated nitrogen compounds ranging from theoretical investigation of hypothetical molecules to the practical application of real-world energetic materials. The review is intended to provide detailed chemical insight into the synthesis and decomposition of such materials as well as foundational knowledge of energetic science new to most chemists.The uptake by plants from soil is one of the first steps for hexachlorocyclohexane (HCH) isomers to enter the food web. However, the HCH transformation associated with the uptake process is still not well understood. Therefore, a soil-wheat pot experiment was conducted to characterize the HCH transformation during wheat growth using compound-specific isotope analysis (CSIA) and enantiomer fractionation. The results showed that the δ13C and δ37Cl values of β-HCH remained stable in soil and wheat, revealing no transformation. In contrast, an increase of δ13C and δ37Cl values of α-HCH indicated its transformation in soil and wheat. A shift of the enantiomer fraction (EF) (-) from 0.50 to 0.35 in soil at the jointing stage and 0.35 to 0.57 at the harvest stage suggested that the preferential transformation of enantiomers varied at different growth stages. Based on the dual element isotope analysis, the transformation mechanism in the soil-wheat system was different from that in wheat in hydroponic systems. The high abundance of HCH degraders, Sphingomonas sp. and Novosphingobium sp., was detected in the α-HCH-treated rhizosphere soil, supporting the potential for biotransformation. The application of CSIA and EF allows characterizing the transformation of organic pollutants such as HCHs in the complex soil-plant systems.Tetraphenylphosphonium salts of Co and Fe complexes with alkyl-substituted, tert-butyl (tb), and isopropyl (dp) 2,3-thiophenedithiolate (α-tpdt) ligands, namely, TPP[Co(α-tb-tpdt)2] (3), TPP2[Fe(α-tb-tpdt)2]2 (4a-b), TPP[Co(α-dp-tpdt)2] (5), and TPP[Fe(α-dp-tpdt)2] (6) were prepared and characterized by cyclic voltammetry, single crystal X-ray diffraction, magnetic susceptibility measurements, and 57Fe Mössbauer spectroscopy. Compound 3 and 5 are isostructural with their Au and Ni analogues with a square-planar coordination geometry. Compound 4 presents two polymorphs (4a-b) both showing a Fe(III) bisdithiolene dimerization. The magnetic susceptibility of 3 and 5 exhibits behavior dominated by antiferromagnetic interactions, with room-temperature magnetic moments of 3.40 and 3.36 μB, respectively, indicating that these square-planar Co(III) complexes assume an intermediate spin electronic configuration (S = 1) as supported by multiconfigurational and DFT calculations.Hydrogels prepared from natural polymers have captured extensive attention over the past decades because of their exceptional biocompatibility and nontoxicity, ease of gelation, and functionalization. Thus, natural polymer hydrogels are considered as promising biomaterials that show great potential in the biomedical field. In drug-delivery systems, the extent and the rate with which the drugs reach their targets are highly carrier-dependent, so the demand for intelligent drug-delivery systems is gradually increasing. Recently, natural polymer hydrogels functionalized with magnetic materials have been used as a novel smart response device for drug delivery because of the quick response and remote controllability. This review aims to give the latest advances of magnetic hydrogels based on natural polymers such as polysaccharide, protein, and DNA in drug-delivery systems. Specifically, the first part compares several general synthesis strategies of magnetic natural polymer hydrogels. The applications of magnetic natural polymer hydrogels are described in the second part. For the last part, an overview of the application in drug delivery for the magnetic hydrogels constructed from several representative natural polymers is presented.This study aimed to develop and optimize chemistries to produce alkyne-modified glucagon-like peptide-1(7-36)-amide (GLP-1(7-36)-NH2) libraries, which could be rapidly and efficiently conjugated to other components and screened to identify compounds with the best drug delivery properties, as potential treatments for type 2 diabetes or obesity. For this purpose, the Lys26 (K26) side-chain, and the amino (N)- and carboxy (C)-termini of a dipeptidyl peptidase 4 (DPPIV)-resistant GLP-1 sequence (GLP-1(7-36;A8G)-NH2), were modified with an alkyne (4-pentynoic acid or propiolic acid). These analogs were characterized with respect to human GLP-1 receptor (hGLP-1R) agonist activity, effects on cell viability and human serum stability, revealing that these modifications maintained low (N-terminal; EC50 1.5 × 10-9 M) to subnanomolar (C-terminal and K26, ∼4 × 10-10 M) agonist activity toward hGLP-1, had no effect on cell viability, and for the N-terminal and K26 modifications, increased human serum proteolytic stabilityvery via a nonparenteral route).A highly transparent cellulose film with a high built-in haze is emerging as a green photonic material for optoelectronics. HMR-1275 Unfortunately, attaining its theoretical haze still remains a challenge. Here, we demonstrate an all-cellulose composite film with a 90.1% transmittance and a maximal transmission haze of 95.2% close to the theoretical limit (∼100%), in which the entangled network of softwood cellulose fibers works as strong light scattering sources and regenerated cellulose (RC) with undissolved fibril bundles functions as a matrix to simultaneously improve the optical transparency and transmission haze. The underlying mechanism for the ultrahigh haze is attributed to microsized irregularities in the refractive index, arising primarily from the crystalline structure of softwood fibers, undissolved nanofibril bundles in RC, and a small number of internal cavities. Moreover, the resulting composite film presents a folding resistance of over 3500 times and good water resistance, and its application in a perovskite solar cell as an advanced light management layer is demonstrated.