Water-induced electrode poisoning and the mitigation strategy for high temperature polymer electrolyte membrane fuel cells

Engineering failure of membrane electrode assembly caused by increasingly fuel poisoning in the high temperature polymer electrolyte membrane fuel cells fed with humidified reformate gases is firstly demonstrated herein this work. Based on the results of the in-situ environmental scanning electron microscope, electrochemical analyses, and limiting current method, a water-induced phosphoric acid invasion model is constructed in the porous electrode to elucidate the failure causations of the hindered hydrogen mass transport and the enhanced carbon monoxide poisoning. To optimize the phosphoric acid distribution under the inevitably humidified circumstance, a facile and effective strategy of constructing acid-proofed electrode is proposed and demonstrates outstanding stability with highly humidified reformate gases as anode fuel. This work discusses a potential defect that was rarely studied previously under practical working circumstance for high temperature polymer electrolyte membrane fuel cells, providing an alternative opinion of electrode design based on the fundamental aspects towards the engineering problems.

FPGA implementation and image encryption application of a new PRNG based on a memristive Hopfield neural network with a special activation gradient

A memristive Hopfield neural network(MHNN)with a special activation gradient is proposed by adding a suitable memristor to the Hopfield neural network(HNN)with a special activation gradient.The MHNN is simulated and dynamically analyzed,and implemented on FPGA.Then,a new pseudo-random number generator(PRNG)based on MHNN is proposed.The post-processing unit of the PRNG is composed of nonlinear post-processor and XOR calculator,which effectively ensures the randomness of PRNG.The experiments in this paper comply with the IEEE 754-1985 high precision32-bit floating point standard and are done on the Vivado design tool using a Xilinx XC7 Z020 CLG400-2 FPGA chip and the Verilog-HDL hardware programming language.The random sequence generated by the PRNG proposed in this paper has passed the NIST SP800-22 test suite and security analysis,proving its randomness and high performance.Finally,an image encryption system based on PRNG is proposed and implemented on FPGA,which proves the value of the image encryption system in the field of data encryption connected to the Internet of Things(Io T).

A mix & act liposomes of phospholipase A2-phosphatidylserine for acute brain detoxification by blood‒brain barrier selective-opening

In the treatment of central nervous system disease,the blood-brain barrier(BBB)is a major obstruction to drug delivery that must be overcome.In this study,we propose a brain-targeted delivery strat-egy based on selective opening of the BBB.This strategy allows some simple bare nanoparticles to enter the brain when mixed with special opening material;however,the BBB still maintains the ability to completely block molecules from passing through.Based on the screening of BBB opening and matrix delivery mate-rials,we determined that phospholipase A2-catalyzed 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoserine li-posomes can efficiently carry drugs into the brain immediately.At an effective dose,this delivery system is safe,especially with its effect on the BBB being reversible.This mix&act delivery system has a simple structure and rapid preparation,making it a strong potential candidate for drug delivery across the BBB.