Emodin induces apoptosis of concanavalin A-stimulated murine splenocytes

Food Science and Biotechnology - Emodin, one of the major compounds in the herb Reynoutria elliptica, is known to maintain immunosuppressive, anti-allergic, anti-cancer, and anti-inflammatory...     

Stable benzimidazole-incorporated porous polymer network for carbon capture with high efficiency and low cost

Porous Polymer Networks (PPNs) are an emerging category of advanced porous materials that are of interest for carbon dioxide capture due to their great stabilities and convenient functionalization processes. In this work, an intrinsically-functionalized porous network, PPN-101, was prepared from commercially accessible materials via an easy two-step synthesis. It has a BET surface area of 1095 m²/g. Due to the presence of the benzimidazole units in the framework, its CO₂ uptake at 273 K reaches 115 cm³/g and its calculated CO₂/N₂ selectivity is 199, which indicates its potential for CO₂/N₂ separation. The great stability, large CO₂/N₂ selectivity and low production cost make PPN-101 a promising material for industrial separation of CO₂ from flue gas. Its H₂ and CH₄ uptake properties were also investigated.     

Effects of the alkylamine functionalization of graphene oxide on the properties of polystyrene nanocomposites

Alkylamine-functionalized graphene oxides (FGOs) have superior dispersibility in low-polar solvents and, as a result, they interact with low-polar polymers such as polystyrene. In this work, the functionalization of graphene oxide using three types of alkylamines, octylamine (OA), dodecylamine (DDA), and hexadecylamine (HDA), was performed, and nanocomposites of polystyrene (PS) and FGOs were prepared via solution blending. Different dispersions of FGOs over PS were obtained for the three alkylamines, and the properties of the PS composites were influenced by the length of the alkylamine. A better thermal stability was observed with a longer chain length of the alkylamine. On the other hand, functionalization with the shortest chain length alkylamine resulted in the highest increase in the storage modulus (3,640 MPa, 140%) at a 10 wt.% loading of FGO.     

Fine liquid blowing: A high Reynolds number,high production rate nanofiber manufacturing technique

A novel gas-assisted jetting process, term fine liquid blowing, is used to improve the production rate of making nanofiber from polymer solution. A high-velocity gas stream is introduced through a central protruding core needle, while a liquid is introduce via an adjacent satellite needle. This arrangement avoids passing the high-velocity gas over the surface of the slow flowing liquid and results in the stable acceleration of the liquid flow on its approach to the tip of the core needle, where it interacts with the high-velocity gas, initiating numerous liquid jets at elevated Reynolds numbers of up to more than 800. The method was used to produce poly (vinyl alcohol) nonwoven fiber mats at polymer solution feed rates of up to 900 mL h, surpassing other conventional methods. The produced fibers were of diameters ranging from 96 to 430 nm. Over the tested range, polymer flow rate did not show significant influence on the resulting fiber diameter. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47384.     

Synthesis of Benzo[a]fluorene,Benzo[c]fluorene,and Benzo[j]fluoranthene via a Lewis Acid-Catalyzed Prins-Type Cycloaromatization: Application to the Total Synthesis of Viridistratin A

Synthesis of benzo[a]fluorene, benzo[c]fluorene, and benzo[j]fluoranthene have been accomplished from readily accessible enol ether precursors via a Lewis acid-catalyzed Prins-type cycloaromatization. Mechanistically, it was proposed that Lewis acids catalyze the generation of oxonium species, which accelerate subsequent annulation and aromatization. This protocol offers the benefit of an operationally simple, transition-metal-free, and air-tolerant reaction condition, enabling gram-scale syntheses of the desired products. The total synthesis of viridistratin A further supported this synthetic strategy for establishing polycyclic aromatic hydrocarbon architectures.     

Comparative Study of Hydrogen Embrittlement of Three Heat-resistant Cr-Mo Steels Subjected to Electrochemical and Gaseous Hydrogen Charging

Hydrogen embrittlement (HE) behaviors of low carbon steel and three heat-resistant Cr-Mo steels having different Cr contents were compared through tensile testing, silver decoration, and blistering observation after electrochemical hydrogen charging and hardness testing after gaseous hydrogen charging. It was observed that higher Cr content caused a longer suppression in charging hydrogen into the steels. However, under hydrogen supersaturation conditions, the higher the strength of the heat-resistant steels, the poorer the HE resistance after electrochemical charging. In contrast, the higher the Cr content, the better the HE resistance under high-temperature gaseous charging conditions.