基于多参数特征保留的载荷谱加速耐久性编辑

为了得到时间更短加载效果相同的加速耐久性试验载荷谱,提出了基于多参数特征保留的载荷谱编辑方法。该方法同时考虑载荷谱的损伤、功率谱密度以及统计参数等信息,对零部件载荷谱的时间进行压缩。以汽车悬架螺旋弹簧的载荷谱为例,采用该方法进行缩减,同时从多个参数特征方面与传统的基于损伤保留的编辑方法所得到的载荷谱进行对比。为了进一步验证编辑效果,采用编辑谱和原始谱对弹簧进行疲劳仿真。结果表明,该方法能够有效缩短汽车零部件的载荷谱,可得到与原始载荷谱具有相同加载效果的编辑载荷谱。     

Mechanisms of EGFR Resistance in Glioblastoma

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. Despite numerous efforts to target epidermal growth factor receptor (EGFR), commonly dysregulated in GBM, approaches directed against EGFR have not achieved the same degree of success as seen in other tumor types, particularly as compared to non-small cell lung cancer (NSCLC). EGFR alterations in glioblastoma lie primarily in the extracellular domain, unlike the kinase domain alterations seen in NSCLC. Small molecule inhibitors are difficult to develop for the extracellular domain. Monoclonal antibodies can be developed to target the extracellular domain but must contend with the blood brain barrier (BBB). We review the role of EGFR in GBM, the history of trialed treatments, and the potential paths forward to target the pathway that may have greater success.     

Zr-4合金板材真空退火温度场的数值模拟

分析Zr-4合金板材真空退火过程中的传热方式,计算锆合金板材径向传热系数,利用ABAQUS对Zr-4合金板材退火温度场进行数值模拟,分析工装夹具对锆合金板材退火的影响,结果表明,工装夹具能改善锆合金板材温度场分布均匀性,使锆合金板材温度分布的最高温差由70 ℃降低至35 ℃,升温过程更加稳定,并且数值模拟结果与实测结果有较好的一致性。     

Anomalous crystal structure of γ" phase in the Mg-RE-Zn(Ag) series alloys:Causality clarified by ab initio study

The crystal structure of the single-unit-cell thickness γ " phase,as a key strengthening phase in Mg-REZn(Ag) series alloys,has been extensively studied,and several structural models have been proposed in the past two decades.However,these reported models,and even the lattice constants at the same proposed structure,are scattered severely,which has led to considerable confusion and not available for further mechanical property simulation and prediction of Mg alloys containing this phase.In this study,by using first-principles calculations,the crystal structure of y" phase is clarified,resolving the discrepancies among different experiments,and its intrinsic mechanical properties have also been studied for the first time.It is verified that the γ " phase contains quasi-five atomic layers,instead of the previously reported tri-layer,and surprisingly,its crystal structure has many variants,which would change with the alloy composition.Besides,with the help of the simulated selected area electron diffraction(SAED) patterns,it is found that the atoms in the central layer remain partially ordered distribution,and this ordered extent primarily depends on the atomic ratio of RE:Zn(Ag) and the solute content in an alloy.That is,the ordered extent increases with decreasing the atomic ratio of RE:Zn(Ag) and/or increasing solute content of alloy,and vice versa.Ag and Zn dissolved in the γ" phase would produce almost opposed mechanical anisotropy for the γ " phase under the identical crystal structure,and the addition of Ag shows more efficient on increasing the shear modulus of γ" phase.     

Fabrication of fullerene decorated by iron compound and its effect on the thermal stability and flammability for high-density polyethylene

Fullerene decorated by iron compound (C₆₀-Fe) is fabricated via solution reaction and characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), wide-angle X-ray diffraction (XRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Upon incorporating C₆₀-Fe into high-density polyethylene (HDPE) matrix by melt blending, the thermal and thermo-oxidative stability of HDPE are considerably increased, the oxidative induction time (OIT) is dramatically extend. When the concentration of C₆₀-Fe reached 5 wt%, the onset degradation temperature in air increased from 352°C to 422°C, and the OIT dramatically delayed from 4.5 to 47.8 minutes. Moreover, from microscale combustion calorimetry (MCC), C₆₀-Fe can reduce the peak heat release rate (PHRR), heat release capacity (HRC), and total heat release (THR) values of the composites, all of which are very important parameters for evaluating the fire retardancy of a polymeric material.     

户内热转印粉末涂料用混合型聚酯树脂的合成研究

通过分析热转印性能的影响因素合成了不同结构的聚酯树脂，研究了树脂酸值对热转印性能的影响，同时研究了部分单体对聚酯树脂热转印性能的影响。采用 DSC热分析法研究了固化促进剂对粉末涂料固化行为的影响，结果表明：选择合适的固化促进剂对涂层转印性能的提高有至关重要的作用。     

喷射成形Al-Zn-Mg-Cu合金挤压态的组织和力学性能

研究了利用喷射成形辅以挤压制备Al-5.72Zn-2.36Mg-1.66Cu合金后优化的组织结构特征和力学性能。结果表明,合金基体组织均匀细化,晶粒形貌趋于圆整,平均晶粒大小达到10 μm左右。当合金的冷却条件通过快速凝固技术改变时,会产生不同程度的固溶强化效果和第二相弥散强化效果,从而改善了合金的整体性能。合金的屈服强度和抗拉强度分别平均提高了20%左右,且伸长率也略有提高。