다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Materials with good flexibility and high conductivity that can provide electromagnetic interference (EMI) shielding with minimal thickness are highly desirable, especially if they can be easily processed into films. Two-dimensional metal carbides and nitrides, known as MXenes, combine metallic conductivity and hydrophilic surfaces. Here, we demonstrate the potential of several MXenes and their polymer composites for EMI shielding. A 45-micrometer-thick Ti3C2Tx film exhibited EMI shielding effectiveness of 92 decibels (>50 decibels for a 2.5-micrometer film), which is the highest among synthetic materials of comparable thickness produced to date. This performance originates from the excellent electrical conductivity of Ti3C2Tx films (4600 Siemens per centimeter) and multiple internal reflections from Ti3C2Tx flakes in free-standing films. The mechanical flexibility and easy coating capability offered by MXenes and their composites enable them to shield surfaces of any shape while providing high EMI shielding efficiency.

Electromagnetic interference shielding with 2D transition metal carbides (MXenes)

Metal Oxides and Oxysalts as Anode Materials for Li Ion Batteries

Conductometric semiconducting metal oxide gas sensors have been widely used and investigated in the detection of gases. Investigations have indicated that the gas sensing process is strongly related to surface reactions, so one of the important parameters of gas sensors, the sensitivity of the metal oxide based materials, will change with the factors influencing the surface reactions, such as chemical components, surface-modification and microstructures of sensing layers, temperature and humidity. In this brief review, attention will be focused on changes of sensitivity of conductometric semiconducting metal oxide gas sensors due to the five factors mentioned above.

Metal oxide gas sensors: Sensitivity and influencing factors

We developed two-step solution-phase reactions to form hybrid materials of Mn3O4 nanoparticles on reduced graphene oxide (RGO) sheets for lithium ion battery applications. Mn3O4 nanoparticles grown selectively on RGO sheets over free particle growth in solution allowed for the electrically insulating Mn3O4 nanoparticles wired up to a current collector through the underlying conducting graphene network. The Mn3O4 nanoparticles formed on RGO show a high specific capacity up to ~900mAh/g near its theoretical capacity with good rate capability and cycling stability, owing to the intimate interactions between the graphene substrates and the Mn3O4 nanoparticles grown atop. The Mn3O4/RGO hybrid could be a promising candidate material for high-capacity, low-cost, and environmentally friendly anode for lithium ion batteries. Our growth-on-graphene approach should offer a new technique for design and synthesis of battery electrodes based on highly insulating materials.

Mn3O4-Graphene Hybrid as a High Capacity Anode Material for Lithium Ion Batteries

http://ieeexplore.ieee.org/iel5/4134878/4084516/04135086.pdf

A NovelDesign andFabrication ofV TypeValve Microactuator withPZTPrepared bySol-Gel

High-quality bio-oil production via catalytic pyrolysis of biocrude oil from hydrothermal liquefaction of microalgae Spirulina

MXene for multifunctional electromagnetic protection

Microwave-driven strategy shows many advantages including selective energization, uniform heating, and high penetration depth, which is a hot topic in wireless actuators. Understanding microwave stimulus-response mechanisms is the key to developing universal construction strategies for advanced microwave-driven actuators. Herein, reduced graphene oxide (rGO) with specified dielectric genes and thermal properties is implanted into the shape memory polymer, liquid crystal elastomer (LCE) as an example, to construct soft, reversible, and sensitive microwave actuators. Based on the analysis of microstructure and dielectric properties, LCE-rGO composites exhibit excellent polarization relaxation-dominated dielectric loss and electromagnetic (EM) energy conversion ability. The maximum dielectric loss factor (ε″) and loss tangent (tan δe) of LCE-rGO are dramatically increased by 216% and 87.5% compared to pure LCE, respectively, and the optimum apparent energy harvest efficiency is 19.4 times higher than that of LCE. In addition, the implantation of rGO significantly lowers the microwave actuation threshold of LCE-rGO composites and reinforces their stimulus-response capacity. Response time under 750 W microwave irradiation of LCE-rGO is shortened to <10s. These findings can provide a solid basis for the design and fabrication of highly efficient microwave stimuli-responsive polymers and enlighten a new approach to wireless actuated smart devices. 

Mao-Sheng Cao

Papers

A NovelDesign andFabrication ofV TypeValve Microactuator withPZTPrepared bySol-Gel

High-quality bio-oil production via catalytic pyrolysis of biocrude oil from hydrothermal liquefaction of microalgae Spirulina

MXene for multifunctional electromagnetic protection

Graphene Implanted Shape Memory Polymers with Dielectric Gene Dominated Highly Efficient Microwave Drive

A New Look of Quantified Methods for Arsenic Speciation and Risk During Hydrothermal Liquefaction