Development of cost-effective nanocrystalline multi-component(Ce,La,Y)-Fe-B permanent magnetic alloys containing no critical rare earth elements of Dy,Tb,Pr and Nd

Here we first report the fully abundant rare earth(RE)-based nanocrystalline multi-component(Ce,La,Y)-Fe-B alloys containing no critical RE elements of Nd,Pr,Dy,and Tb by melt-spinning technique.The roles of La and Y substitutions for Ce have been fully understood.La plays a positive role on both thermal stability and room-temperature(RT)magnetic properties.The enhanced coercivity Hcj by partial substitution of La is attributed to the increases of anisotropy field HA and the formation of continuously distributed grain boundaries resulting from the suppression of CeFe2 phase.Although Y substitution is not benefit for Hcj,both remanent polarization Jr and thermal stability have been effectively improved since Y2Fe14B shows relatively high saturation magnetization Ms and a positive temperature coefficient of HA over a certain temperature range.In addition,RE element segregation has been confirmed,La prefers to enter into the grain boundaries than Ce and Y prefers to remain in the 2∶14∶1 phase.Based on these understanding,a series of melt-spun(Ce,La,Y)-Fe-B alloys have been designed.A relatively good combination of magnetic properties with maximum energy product(BH)max=7.4 MGOe,Hcj=400 kA/m,and Jr=0.63 T has been obtained in[(Ce0.8La0.2)0.7Y0.3]17Fe78B6 alloy,together with high Curie temperature(Tc=488 K)and low temperature coefficients of remanence(α=-0.255％/K)and coercivity(β=-0.246％/K).     

定远县城北水库自来水厂地下取水管道部位土坝坡脚渗漏分析

水库作为城市给水水源，必须处理好穿过坝体取水管道部位渗漏问题。本文具体分析了定远县城北水库取水管道部位土坝坡脚渗漏问题，并采取了相应的工程措施，既保证了大坝的安全，又避免了封堵旧的取水管道、设计施工新的取水管道而带来的人力、物力的浪费。     

基于神经网络的曲面加工振动监测方法

文章论述了一种新的基于传感器信息的切削加工振动预测方法，提出了切削状态指数的概念，用于描述切削状态，利用神经网络规划切削条件与切削状态的非线性关系，给出了曲面加工切削振动状态的变化规律。     

OPEN ARCHITECTURE CNC SYSTEM HITCNC AND KEY TECHNOLOGY

Aiming at the characteristics of modularity and reconfigurable in open architecture com-puter numerical control (CNC) system,the open architecture CNC system,Harbin Institute of Tech-nology computer numerical control (HITCNC),is researched and manufactured based on the interface standards. The system’s external interfaces are coincident with the corresponding international stan-dards,and the internal interfaces follow the open modular architecture controller (OMAC) agreement. In the research and manufacturing process,object-oriented technology is used to ensure the openness of the HITCNC,and static programming is applied in the CNC system according to the idea of modu-larization disassembly. The HITCNC also actualizes real-time and unreal-time modules adopting real-time dynamical linked library (RTDLL) and component object model (COM). Finite state ma-chine (FSM) is adopted to do dynamically modeling of HITCNC. The complete separation between the software and the hardware is achieved in the HITCNC by applying the SoftSERCANS technique. The application of the above key techniques decreases the programming workload greatly,and uses software programs replacing hardware functions,which offers plenty technique ensures for the open-ness of HITCNC. Finally,based on the HITCNC,a three-dimensional milling system is established. On the system,series experiments are done to validate the expandability and interchangeability of HITCNC. The results of the experiments show that the established open architecture CNC system HITCNC is correct and feasible,and has good openness.     

Microstructure of pre-sintered permanent magnetic strontium ferrite powder

The microstructure and characteristics of pre-sintered strontium ferrite powderwere investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The present study shows that the pre-sintered strontium ferrite powder is provided with a certain particle size distribution, which results in high-density magnets. The strontium ferrite particle has a laminar hexagonal structure with a size similar to ferrite single domain. Ferric oxidephase due to an incomplete solid phase reaction in the first sintering is discovered, which will deteriorate the magnetic properties of ferrite magnet. In addition, the waste ferrite magnets with needle shape arranging along C axis in good order into the powders are found, which have no negative effects on finished product quality.     

GA与PSO的混合研究综述

传统算法无法满足现代大规模、多变量、多约束的复杂问题求解,使得智能算法的应用越来越广泛。但单一智能算法在解决很多复杂问题时依然存在不足,利用算法之间互补性的混合算法便应运而生,并且取得了较好的实验效果,被越来越多的国内外学者所关注。以混合方式为研究主线,对智能算法中的遗传算法（GA）和粒子群算法（PSO）的融合方式进行分析与综述,并对其进一步的研究发展方向进行了探讨。     

STEP-NC铣削仿真系统开发

STEP—NC是新一代数控标准。提出了一个由STEP—NC驱动的铣削仿真系统，阐述了系统的结构组成，讨论了各部分的实现技术与方法。简要介绍了STEP—NC数控标准，详细地介绍了系统每一模块的实现方法，最后，说明了所开发的仿真系统的意义和STEP数控系统的发展方向。     

基于人工表面等离激元的天线研究进展

人工表面等离激元是在人工电磁媒质与传统材料界面激发的一种亚波长表面电磁模式, 具有波长短、场局域增强、色散可调等新奇的电磁特性, 在小型化微波器件、隐身材料与隐身结构、天线/天线罩等领域具有重要应用前景.文章综述了人工表面等离激元在天线中的应用研究进展, 包括基于混合模式耦合、相位梯度超表面解耦、周期结构解耦等原理的端射天线、多波束天线、频扫天线, 为新型天线的研发与应用提供技术支撑.     

复合材料缠绕法的对比研究

复合材料缠绕成型技术已成为复合材料加工的重要工艺.详细研究了2种复合材料缠绕加工方法:参数化缠绕法(parameter winding method,PWM)和网格缠绕法(mesh winding method,MWM),并分别用2种方法对叶片进行了缠绕成型实验.依据叶片缠绕实验的效果,从缠绕的设计、线型规划以及最终效果等方面对比分析2种缠绕法.结果表明:MWM比传统PWM在异型构件的缠绕成型方面更具灵活、方便、高效的优点.     

胡桃醌对人卵巢癌SKOV3和IOSE80细胞增殖和侵袭的抑制作用及其机制研究

目的: 研究胡桃醌对人卵巢癌SKOV3和IOSE80细胞增殖和侵袭的抑制作用,并从信号通路深入探讨其作用机制。方法: 体外培养人卵巢癌SKOV3细胞和IOSE80细胞,给予不同浓度的胡桃醌溶液干预,MTT比色法检测细胞增殖,划痕实验检测细胞迁移,Transwell检测细胞转移,流式细胞术检测细胞凋亡,Western Blot检测AKT、ERK、NF-κB信号通路蛋白表达,RT-PCR检测波形蛋白(vimentin)、基质金属蛋白酶-2（MMP-2）、基质金属蛋白酶-9（MMP-9）mRNA表达。 结果: 不同浓度胡桃醌可抑制SKOV3细胞和IOSE80细胞增殖活力,降低细胞侵袭能力,加速细胞凋亡,且随浓度的增加对细胞增殖、侵袭和凋亡的作用越明显,差异均有统计学意义（P<0.05）。不同浓度胡桃醌均可抑制SKOV3细胞和IOSE80细胞AKT、ERK、NF-κB信号通路蛋白的表达,且随浓度的增加信号通路蛋白表达减少,差异均有统计学意义（P<0.05）。不同浓度胡桃醌均可减少SKOV3细胞和IOSE80细胞Vimentin、MMP-2、MMP-9 mRNA的表达,且随浓度的增加mRNA表达减少,差异均有统计学意义（P<0.05）。结论: 胡桃醌可抑制SKOV3和IOSE80细胞体外增殖、转移,促进凋亡,其机制与抑制AKT、ERK、NF-κB信号通路表达和下调Vimentin、MMP-2、MMP-9 mRNA表达有关。