Surface Profile Optimization of Yankee Dryer Based on Finite Element Analysis

The deformation and stress distribution of cast iron Yankee dryer caused by outside linear load， inside steam pressure and self-gravity were calculated by numerical simulation with ANSYS software. The deformation curve of the linear load area was obtained and compared with the deformation in the actual working process. The surface profile of dryer was optimized and the deformation and stress of the optimized dryer were calculated and compared with the that of before optimization. In this paper， the method of the surface profile optimization of Yankee dryer was presented．     

Investigation on the anti-reduction mechanism of Ti4+ in high dielectric constant system Ca0.9La0.067TiO3 by doping with Al2O3

Ca_0.9La_0.067TiO₃ (abbreviated as CLT) ceramics doped with different amount of Al₂O₃ were prepared via the solid state reaction method. The anti-reduction mechanism of Ti⁴⁺ in CLT ceramics was carefully investigated. X-ray diffraction (XRD) was used to analyze the phase composition and lattice structure. Meanwhile, the Rietveld method was taken to calculate the lattice parameters. X-ray photoelectron spectroscopy (XPS) was employed to study the valence variation of Ti ions in CLT ceramics without and with Al₂O₃. The results showed that Al³⁺ substituted for Ti⁴⁺ to form solid solution and the solid solubility limit of Al³⁺ is near 1.11 mol%. Furthermore, the reduction of Ti⁴⁺ in CLT ceramics was restrained by acceptor doping process and the Q × f values of CLT ceramics were improved significantly. The CLT ceramic doped with 1.11 mol% Al₂O₃ exhibited good microwave dielectric properties: ε_r = 141, Q × f = 6848 GHz, τ_f = 576 ppm/°C.     

沁水盆地赵庄矿3号煤层地面煤层气抽采低产原因分析

在对沁水盆地赵庄矿煤层气开发地质、煤层气生产井资料深入研究的基础上，分析、总结了区内煤层气直井低产原因，并据此提出了区内地面抽采后续开发方向。研究认为:3号煤层气含量偏低、含气饱和度低、临储比低，致使排采阶段气含量可降幅度低，是其低产的宏观表征；3号煤储层不匹配孔级，较差连通性，即微、小孔为主，中孔次之，大孔不发育，微裂隙连通性差，致使扩散缓慢、影响储层改造和抽采效果，是其低产的微观表征；3号煤层远高于顶底板塑性及相近的水平应力，进一步造成改造缝长受限，泄流面积不足。因此，建议区内后续地面抽采方式应以增大泄流面积开发方式为主。     

矿用直线振动筛结构故障分析

针对煤矿选煤厂直线振动筛工作过程中出现的结构故障问题,采用有限元仿真与现场测试结合的方法对振动筛出现故障的原因进行了分析研究。介绍了振动筛的主要结构及常见故障,并以某矿选煤厂发生大梁断裂的振动筛为例,对该振动筛进行三维建模和有限元模态分析,分析结果表明:随着模态阶次的增加,振型的变化逐渐由移动转为结构本身的扭曲变形。在该振动筛空载工作状态下,选用本质安全型便携式测振记录仪进行振动测试并处理测试信号,得到该振动筛的工作频率。结合模态分析结果和实际测试结果,判断出空载时频繁运行振动筛是造成其大梁断裂的主要原因。根据故障原因给出维护建议:应当尽量避免振动筛在空载或物料较少的状态下长时间运行;在振动筛投入使用前,应预先了解振动筛的工作状态及可能存在的薄弱环节,尽可能避免结构故障,保证振动筛可靠运行。     

65号航空冷却液的泡沫倾向性研究

针对65号航空冷却液在过滤循环中出现泡沫较多的现象，对65号航空冷却液泡沫倾向性进行探究。按照石化行业标准《发动机冷却液泡沫倾向测定法（SH /T 0066-2002）》，利用冷却液泡沫倾向测定仪来评价65号航空冷却液泡沫倾向性，并进行水乙二醇溶液对照试验。结果表明，航空冷却液在低温和循环时间较长的情况下，其泡沫倾向性较大，而随着温度的升高和循环时间的缩短，泡沫倾向性有一定程度的改善；并且通过水乙二醇对照试验可知，冷却液的基础液泡沫倾向性较小。航空冷却液在过滤循环中出现的泡沫问题，是加入的添加剂所引起的。     

Discovery of New Antiproliferative Imidazopyrazole Acylhydrazones Able To Interact with Microtubule Systems

Even though immunotherapy has radically changed the search for anticancer therapies, there are still many different pathways that are open to intervention with traditional small molecules. To expand our investigation in the anticancer field, we report here a new series of compounds in which our previous pyrazole and imidazopyrazole scaffolds are linked to a differently decorated phenyl ring through an acylhydrazone linker. Preliminary tests on the library were performed at the National Cancer Institute (USA) against the full NCI 60 cell panel. The best compounds among the imidazopyrazole series were then tested by immunofluorescence staining for their inhibition of cell proliferation, apoptosis induction, and their effect on the cell cycle and on microtubules. Two compounds, in particular 4-benzyloxy-3-methoxybenzyliden imidazopyrazole-7-carbohydrazide showed good growth inhibition, with IC₅₀ values in the low-micromolar range, and induced apoptosis. Both compounds altered the cell-cycle phases with the appearance of polyploid cells. Immunofluorescence analysis evidenced microtubules alterations; tubulin polymerization assays and docking studies suggested the tubulin system to be the possible, although not exclusive, target of the new acylhydrazone series reported here.     

流量伺服阀作压力控制的非典型应用

文章提出并分析了一种用力反馈式流量伺服阀与手动节流阀配合使用,从而对负载进行压力控制的液压桥路。该桥路本质为C型半桥:伺服阀单腔输出,节流阀通过调节回油液阻来调节负载腔压力的起始点,伺服阀根据负载需求改变流量输出。整个压力控制回路为纯机械式控制,稳定可靠,精度可达0.1 bar。     

基于有限元的大流量换向阀仿真分析及结构优化

为了提高大流量换向阀的设计能力,该文采用ANSYS仿真平台对大流量换向阀仿真分析及结构优化。研究结果表明:撞击阶段应力集中区域基本出现在二级阀芯径向进油口部位,此时形成的最大应力等于24.26 MPa,明显比682 MPa的材料屈服极限更低。进液阀套达到了271.83 MPa的最大压应力,但明显低于682 MPa的屈服极限,表明壁厚满足设计标准。进液阀套形最大应力出现在阀套内部,跟瞬态冲击条件下最大应力出现区域存在明显差异。二级阀芯最大应力都出现于阀芯部位,完成结构优化之后,二级阀芯的最大应力发生了显著降低,其余各部位的应力也显著减小,可以满足设计标准。     

新型卡板式外径千分表的设计应用

针对机车牵引电机转轴磨削测量中,对转轴轴承位尺寸超差的原因进行分析,设计制作机车牵引电机转轴新型卡板式外径千分表(实用新型:ZL201420477030.7)。实际应用表明,新型卡板式外径千分表保证了牵引电机转轴轴承位的磨削尺寸,避免了转轴轴承位尺寸超差现象,解决了机车牵引电机转轴轴承位磨削测量的工艺、质量问题。     

基于关键拓扑变动项辨识的调度操作潮流校核方法

为解决传统调度操作潮流校核中的有效性问题，定义了一种面向调度操作的关键拓扑变动概念，提出并实现了基于关键拓扑变动辨识的调度操作潮流校核方法。首先，剖析了调度操作安全校核的实施目的，围绕其运行断面潮流校验的校核目的，定义了面向调度操作的关键拓扑变动概念，并基于网络拓扑连接关系设计了其辨识方法。在此基础上，提出了基于关键拓扑变动项辨识的调度操作潮流校核方法，明确了其实施流程和要点。最后基于当前电网调度自动化系统实际，构建了其实施框架，并介绍了其在某电网的实施效益。