Realizing the invariant electrostrain response and low hysteresis via multicomponent coordination in Pb-based ceramics

High-performance piezoelectric materials are essential in many piezoelectric devices. However, the composition of piezoelectric materials usually has a great influence on their performance. In this work, xBi(Mg_1/2Ti_1/2)O₃–yPbZrO₃–zPbTiO₃ (xBMT–yPZ–zPT; 0.2 ≤ x ≤ 0.4, 0.25 ≤ y ≤ 0.4, and 0.35 ≤ z ≤ 0.4) ternary ceramics with different compositions were synthesized and it was found that the strain response was not sensitive to the composition. The crystal structure, strain response, ferroelectric properties, and temperature stability of xBMT–yPZ–zPT ceramics were investigated in detail. X-ray diffraction patterns show that all the as-prepared xBMT–yPZ–zPT ceramics with x = 0.2, 0.3, 0.4, and 0.5 possess a perovskite structure. Under an external electric field of 6 kV mm⁻¹, the strain values of xBMT–yPZ–zPT ternary ceramics with x = 0.2, 0.3, 0.4, and 0.5 were 0.30%, 0.31%, 0.30%, and 0.27%, respectively. In addition, the strain hysteresis of these ternary ceramics is also almost the same and low. These merits make xBMT–yPZ–zPT piezoelectric ceramics have broad application prospects in the field of commercial actuators.     

The Neutron-Gamma Pulse Shape Discrimination Method for Neutron Flux Detection in the ITER

The neutron flux monitor (NFM), as a significant diagnostic system in the International Thermonuclear Experimental Reactor (ITER), will play an important role in the readings of a series of key parameters in the fusion reaction process. As the core of the main electronic system of the NFM, the neutron-gamma pulse shape discrimination (n-γ PSD) can distinguish the neutron pulse from the gamma pulse and other disturbing pulses according to the thresholds of the rising time and the amplitude pre-installed on the board, the double timing point CFD method is used to get the rising time of the pulse. The n-γ PSD can provide an accurate neutron count.     

制革污泥及施含铬污泥土壤中铬含量测定方法的研究

对浓H     

中俄氟硅橡胶生胶性能对比

对国产氟硅橡胶生胶ＳＦ－ ２ 和俄罗斯产氟硅橡胶生胶ＣКＴΦＴ－ １００ 的基本性能进行了对比。结果表明： ＳＦ－ ２ 的耐热性能较差, 其它性能与ＣКＴΦＴ－ １００ 基本相同; 以ＳＦ－ ２ 为基胶的硫化胶经２００ ℃, ７０ ｈ 热空气老化后的性能较差, 其它性能与ＣКＴΦＴ－ １００ 没有明显差异。在空气中ＣКＴΦＴ－ １００ 生胶热失重的起始分解温度比ＳＦ－ ２ 高１５ ℃, 在氮气中比ＳＦ－ ２ 高３２ ℃。ＣКＴΦＴ－ １００ 具有更好的耐热稳定性能。     

电化学氧化法处理高浓度氨氮废水研究

采用电化学氧化法去除皮革废水中的高浓度氨氮,对氨氮降解过程中的重要影响因素做了研究。结果显示．氨氮的去除包括直接氧化和间接氧化过程。对于初始氨氮浓度5000mg／L的高浓度氨氮废水,使用DSA阳极、石墨阴极,在电流2．5A,初始pH=10,氯离子浓度30000mg／L,极板间距2．5cm条件下,氨氮去除率在180min内可以达到100％。较低浓度氨氮废水更适合电化学氧化,但是能耗相对较高。综合考虑降解效果及能耗．电化学氧化法是一种很好的氨氮去除技术。     

制革污泥生物淋滤液鞣革回用可行性研究

生物淋滤技术脱除制革污泥中的Cr后,淋滤液中大量的Cr可在制革中得以回用,研究结果表明:将淋滤液用于浸酸、鞣制工艺后,蓝皮的收缩温度、吸Cr量与常规鞣制获得的蓝皮的指标差异不大,但当淋滤液中的Fe、Ca、Mg、K含量较高时,会对成革产生影响,其中影响最大的主要是Fe,表现在降低了Cr的吸收量,使皮面颜色变深。     

济钢1750m~3高炉炉役后期炉缸侵蚀分析及对策

炉役后期的护炉生产实践以及炉缸侵蚀模型表明,济钢2#1 750 m3高炉炉缸侧壁呈现为较大蘑菇型侵蚀。分析认为炉缸侵蚀的主要原因是铁水环流的影响以及炉缸局部热流强度过高;另外,90°的铁口夹角布置以及长期频繁使用洗炉剂也加剧了炉缸的侵蚀。通过改进灌浆操作,开发局部强化冷却技术,提高了炉缸的冷却效果。同时优化操作制度,有效减缓了砖衬的侵蚀,保证了炉役后期炉缸工作本质安全。     

聚脲润滑脂的制备与性能研究

以矿物油和聚α-烯烃为基础油,利用二异氰酸酯与有机胺反应制备聚脲润滑脂。探讨了基础油、有机胺、异氰酸酯等组成及制备工艺条件对聚脲润滑脂性能的影响,并通过组成和工艺条件的优化制备出性能优良的聚脲润滑脂。制备的聚脲润滑脂具有高滴点和良好的胶体安定性、氧化安定性、防腐性和抗磨极压性。     

数控端面外圆磨床成形砂轮的修整方法

介绍一种不带斜轴功能数控系统的数控端面外圆磨床,运用宏程序对X轴(砂轮架)倾斜角度的三角函数计算与插补控制,实现对其成形砂轮进行修整的方法。为了更好地加工轴类零件的端面,且保证能安全地磨削加工砂轮,数控端面外圆磨床的砂轮架与工作台的角度应为60°,使砂轮斜切入磨削加工。在成形砂轮修整时,由于X轴与Z轴并非垂直,而是成60°,因此,需再对修整程序进行三角函数的计算和程序插补控制,使Z轴跟随X轴自动插补,将砂轮修整出理想的轮廓状态。