大行程纳米级步距压电电动机

介绍了一种基于尺蠖运动原理的大行程纳米级步距压电电动机。在结构设计方面,变传统单驱动器结构为双驱动器结构,采用新颖的推—拉接力运动原理,配以适当的四路驱动信号,实现了压电电动机的连续匀速运动。通过试验对电动机的性能进行了测试,结果表明：电动机的运动位移是线性的,运动速度在驱动电压为300 V时可达12 mm/s,最小步距小于6 nm,行程大于10 mm。     

实现物体360°轮廓测量的新型轮廓拼接方法

提出一种新型轮廓拼接技术用来实现复杂物体的360°几何轮廓的测量。应用光栅投射三维轮廓技术使被测物绕旋转轴进行多次旋转,获得能覆盖整个物面的多个单视角的三维坐标,利用坐标变换将这些数据转换到统一的坐标系下,然后应用正负方向掩膜矩阵法拼接合成物体360°轮廓。实践表明,应用该方法物体只需在4个角度0°、90°、180°、270°进行旋转,就能快速得到物体360°轮廓,它不仅可以用于普通连续面形的测量, 又可以用于含有间断的面形即自由曲面的测量。     

乳化炸药油水相流量控制

以乳化炸药生产线油、水相流量控制系统为研究对象,分析油、水相流量添加过程的滞后性,针对传统PID控制理论的不足,详细分析了自校正PID理论,采用自校正PID控制策略来实现流量的实时控制。现场运行情况表明,这种控制策略符合工业实际,采用的控制器稳定可靠。     

Construction of plate-like magnetic heterostructure for synergistic microwave absorption

The dramatically dropped permeability of magnetic materials at gigahertz frequencies, known as the Snoek's limit, has severely constrained the microwave absorbing performance of magnetic materials. To break the Snoek's limit at high frequencies, a plate-like magnetic heterostructure composed of Ni-Fe ferrite, nitride, and Permalloy is fabricated through nitridation of Ni-Fe layered double hydroxide. It has been found that single-phase magnetic flakes or the multi-phase heterostructure with extraordinarily linked magnetic nanoplates can be obtained by simply adjusting the temperature of nitridation. Due to the highly anisotropic morphology and synergistic effect at abundant heterogeneous interfaces, the magnetic heterostructure shows enhanced imaginary permeability that is even higher than that of single-phase Permalloy. Accordingly, the magnetic loss in C and X bands is improved, leading to significant enhancement of attenuation constant in this novel microwave absorber. Combined with the moderate permittivity, the impedance matching of the heterostructure is superior compared to every single component, as well as the mixture of these components. As a result, the minimum reflection loss of −59.30 dB at a thickness of 2.02 mm and effective absorption bandwidth (RL<−10 dB) of 2.44 GHz is realized. These findings provide a novel path to designing high-performance microwave absorbers based on magnetic materials.     

超声辅助酶解大米多肽的制备及其对酵母细胞增殖性影响

采用超声辅助酶解制备大米多肽,并研究其对酵母细胞增殖性的影响。在单因素试验基础上,对超声辅助酶解制备大米多肽进行工艺优化,确定最优超声辅助酶解工艺:超声功率密度51.8 W/L、超声温度50℃、超声时间15 min。在最优工艺条件下,大米多肽得率为70.57%。对酵母细胞培养增殖显示随着多肽浓度的增加而增强,当多肽浓度达到25 g/L后,酵母细胞增殖效果不再增强;另外超声辅助酶解的大米蛋白多肽作为氮源对酵母细胞培养增殖效果要好于常规酶解。     

聚脲基涂层对碳纤维布加固混凝土力学性能影响的研究

为了提高碳纤维布加固混凝土中碳纤维材料与混凝土之间相互作用的性能,研究提出在混凝土和碳纤维布之间增加一层柔性聚脲基涂层,通过模型试验及有限元仿真计算的手段,对比分析了有无聚脲基涂层对碳纤维布加固力学性能的影响。试验结果表明,含有聚脲基涂层时可以改善界面处的粘结性能,提高其剥离承载力和界面剥离破坏能等。基于双线性内聚力的界面粘结—滑移关系曲线,运用有限元分析软件ABAQUS分别对聚脲基涂层有/无两种工况进行非线性有限元仿真分析。模拟结果表明,当含有聚脲基涂层时,数值分析结果和试验结果具有较好的一致性。试验结果和数值解均证明了聚脲基涂层可以提高碳纤维布(CFRP)和混凝土基面之间的极限承载力和界面剥离破坏能,对水工结构碳纤维加固实际应用具有参考价值。     

水轮机水压,转速联合预测控制器研究

本文论述了水轮发电机水压、转速联合预测控制的设计方法,给出了仿真研究结果。水压预测分别在刚性水锤及弹性锤两种情况下进行。仿真结果表明本文方法可明显改善引水道的水击效应,而转速仍具有较好的动态性能。     

制曲温度对酱香型大曲质量的影响

采用各种技术措施适当提高制曲品温,将品温由传统的60℃～65℃提高为65℃～70℃,制备超高温大曲.通过对超高温大曲的红外分析、理化指标测定、感官质晕和酿造酒酒质的评定,探讨制曲温度对大曲质量的影响.试验结果表明,超高温大曲的感官质量优于普通高温大曲,糖化力和酯化力明显低于普通高温大曲,理化指标变化不大.该成品曲含有丰富的蛋白酶和微生物代谢产物,酿造的酱香型白酒酒质醇厚、酱香突出,香气幽雅,回味悠长.     

Design and performance study of a gas-Cherenkov detector with an off-axis parabolic reflector for inertial confinement fusion experiments

In this work, the gas-Cherenkov detector with an off-axis parabolic reflector(Opr GCD) is designed using the Geant4 Monte Carlo simulation toolkit, which is helpful to improve the collection efficiency of Cherenkov photons. The method to study the performance of Opr GCD based on femtosecond laser-wakefield-accelerated electron beams is presented. Cherenkov signals with high signal-to-noise ratio were obtained, and the measured Cherenkov signals changing with the CO2 pressure were consistent well with the simulation results. The design and study of this Opr GCD system lay the foundation for the application of fusion gamma diagnostics system in large laser facilities of China.