粉末冶金温压工艺制备Fe-Cu-C材料

采用两种温压专用润滑剂,在不同温度和压力下以温压技术制备铁基粉末冶金材料,比较其烧结密度的变化,并分析温压工艺对密度的影响。结果表明：此温压工艺在610MPa压制压力、140℃压制温度下可制备出烧结密度最高达到7．18g／cm^3,抗拉强度最高达到550MPa的Fe-2％Cu-1％C铁基粉末冶金材料。     

Investigation of high power laser coatings

1Introduction Opticalthinfilmcoatingisoneofthewea kestopticsinICFlasersystems.Totally,there aretwoaspectswhichinfluencethedevelopment ofthelasersystems.Thefirstaspectislaser damageresistanceofthecoatings,whichpuzzled coatingengineersformanyyears[1].Although muchgreatprogresshasbeenmadeintheoretical analysisofdamagemechanismsandoptimization ofdepositionprocedures,therewerestillmany sealedproblemsrestrictingthefurtherimprove mentofthelaserinduceddamagethreshold(LIDT)[27].Thelaser induceddama…     

低硬度12Cr1MoVG组织和性能研究

通过化学成分分析、显微组织分析、力学性能试验及扫描电镜对低硬度12Cr1Mo VG进行了组织和力学性能分析。结果表明,材料的显微组织为铁素体、珠光体和碳化物,球化2.5级,常温下冲击功及,伸长率远高于标准要求,但抗拉强度低于标准下限。     

铝合金表面微弧氧化Cr2O3复合膜层的制备及表征

在微弧氧化液中添加Cr2O3微粒对6063铝合金进行微弧氧化,研究了电解液中Cr2O3的浓度和各项工艺参数对复合膜层膜厚及表面形貌的影响,并用SEM,EDS等手段对复合膜层的微观形貌及组成进行了表征。结果表明:膜层厚度及Cr2O3的复合量均随着溶液中Cr2O3的含量、电流密度、微弧氧化时间的增加而增加,电解液的pH值对复合沉积量也有影响;复合膜层表面含有大量Cr2O3微粒,且Cr2O3微粒已沉积到了氧化膜内部。     

基于公理设计的挤压铸造设备设计

将公理设计理论引入到铸造设备的设计开发中,系统地分析了挤压铸造设备的公理设计过程.建立了挤压铸造设备公理设计的框架和原则,阐述功能域和物理域的映射分解过程,得到了设计矩阵方程,在此基础上提出了一种挤压铸造设备主要部件的设计顺序.设计结果应用到2500kN的挤压铸造设备开发过程中,改善了设计,提高了设计效率.     

Cr5钢过烧温度的试验分析

借助差示扫描量热仪(DSC)与金相显微分析,对Cr5钢过烧临界温度进行了试验.用Thermo-calc软件模拟了各合金元素对于过烧温度的影响,并对计算结果进行线性回归分析.结果表明,在Cr5钢的成分范围内其合金元素含量与过烧温度基本为单调递减的关系,其中对于过烧温度起主要影响作用的是碳.     

Capsaicin exerts anti-benign prostatic hyperplasia effects via inhibiting androgen receptor signaling pathway

Background: Benign prostatic hyperplasia (BPH) is a common condition in middle-aged and elderly men. Enlargement of the prostate causes lower urinary tract symptoms. Capsaicin is a phytochemical extracted from chili peppers and exerts many pharmacological actions, such as anti-tumor and anti-inflammatory effects. Methods: Our study investigated the effect of capsaicin in vitro and in a mouse model in vivo. A prostatic stromal myofibroblast cell line (WPMY-1) was co-incubated with testosterone (1 µM) and different concentrations of capsaicin (10–100 µM) for 24 and 48 h. Capsaicin (10–100 µM) significantly inhibited testosterone-treated WPMY-1 cell growth at 48 h by MTT assay. The testosterone propionate (7.5 mg/kg)-induced BPH mouse model was used to examine the anti-proliferative effect of capsaicin. Treatment with capsaicin (10 mg/kg) for 14 days significantly attenuated prostatic hyperplasia. Finasteride was used as a positive control. Results: Capsaicin significantly decreased prostate weight and prostate index (prostate/body weight ratio) in BPH mice. The expression of 5α-reductase type II, androgen receptor (AR) and prostate specific antigen (PSA) protein expression and PSA serum were all significantly reduced in capsaicin-treated BPH mice. In addition, capsaicin also activated transient receptor potential vanilloid 1 mediated apoptosis and autophagy in BPH mice. Conclusion: These results demonstrate multiple positive effects of capsaicin in controlling prostate growth and suggest its therapeutic potential in the treatment of BPH.     

纳米氧化物La0.8Sr0.2MnO3的制备研究

用添加表面活性剂的苹果酸溶胶凝胶法制备出纳米钙钛石型氧化物La0.8Sr0.2MnO3。通过差热热失重分析,确定了氧化物的焙烧制度。XRD分析表明,所烧制的氧化物样品特征衍射峰明显,杂峰少,晶形完整,其物相为钙钛石结构。表面活性剂因其亲油基团和亲水基团与胶体粒子可以发生复杂的相互作用,形成胶束和胶团,保护了胶体粒子不长大,从而有效地减小氧化物粉料的颗粒粒径,并且在纳米材料的制备过程中能显著降低纳米微粒的表面张力,从而可防止原生粒子团聚,所以在溶胶的制备过程中添加了表面活性剂聚乙烯醇(PVA)。根据谢乐公式计算得出,添加了PVA后,氧化物粉料的粒径约为17nm。TEM分析表明,聚乙烯醇可以作为纳米氧化物粉体La0.8Sr0.2MnO3的分散剂,添加适量的PVA可使纳米粒子的团聚现象得到了明显改善。     

高炉铁水含硅量的混沌局部线性预测

对莱钢1号高炉(750 m3)、临钢6号高炉(380 m3)铁水含硅量([Si])进行了混沌局部线性预测.结果表明,两 座高炉[Si]的一步预测的命中率在[Si]±0.1％的范围内均达到80.0％以上,对莱钢1号高炉(b)类样本甚至达89.1％,且预 测精度在10-2数量级,对实际生产具有很好的指导作用.     

CAE技术在电视机前壳气辅模具开发中的应用

分析了在气体辅助注射成型技术应用中存在的问题 ,介绍了气辅注射CAE分析的一般流程 ,通过应用MOLDFLOW/MPI软件对电视机前壳模具进行的CAE气辅分析 ,显示了注射CAE技术在气辅模具开发过程中对于布置气道、确定气辅成型工艺参数、预测气体穿透效果等方面所起到的显著作用