The effect of binder phase content on WC-AlCoCrFeNiTi_(0.2) high entropy cemented carbides microstructure and mechanical properties

Thiswork aims to explore WC-G201 high entropy cemented carbides properties fabricated by spark plasma sintering with AlCoCrFeNiTi_(0.2)and WC as binder phase and hard phase respectively.AlCoCrFeNiTi_(0.2)powder and WC powder were mixed at the mass ratio of 5:95,10:90 and 15:85 respectively,and then via SPS at 1300℃for 5min.The results show that the binder phase has good wettability to WC,and with the increase of binder phase content,the hardness of the alloy decreases gradually,fracture toughness increases first and then decreases,the maximum value is 7.88 MPa m1/2.It is estimated that the comprehensive mechanical property of cemented carbides is the best when the binder content is between 5wt%and 10wt%.

生物内源性SO_(2)的荧光检测

SO_(2)作为空气污染物而被人们熟知,但鲜有人知道在生物体内SO_(2)也能内源性生成并作为信号分子参与生物体代谢循环,与我们的健康息息相关。SO_(2)在低浓度的时候具有舒张血管、抑制炎症、抗氧化和调节脂质代谢的作用,而在高浓度的时候则会引起某些呼吸道疾病、神经系统紊乱甚至是癌症。由此可见,更深入和全面地了解SO_(2)对维持生物体内系统的稳态和保持生物健康至关重要。本文以生物体内的SO_(2)为线索,从内源性生成,生理作用和荧光检测三大方面阐述了以SO_(2)为代表的新型信号分子在生物体内的流通和检测手段的演变。