PMMA/SAN共混物相分离温度的确定:几种流变学方法的比较

比较了动态温度扫描、Cole-Cole曲线和似凝胶行为法(损耗角正切的频率依赖性)等3种流变方法在确定聚甲基丙烯酸甲酯(PMMA)/苯乙烯-丙烯腈共聚物(SAN)共混物相分离温度的差异。流变研究结果表明:用动态温度扫描的方法得到的体系相分离温度受动力学效应的影响较为显著,具有频率和升温速率双重依赖性,因此很难通过外推来得到准确相分离温度。Cole-Cole曲线和似凝胶行为法均避免了动力学效应的影响,而Cole-Cole曲线得到的相分离温度要低于似凝胶行为法,这种差别与两种方法对相结构的敏感性有关。此外,还讨论了二氧化硅纳米粒子加入对这3种流变学方法的相分离敏感性的影响。     

桂枝茯苓胶囊联合克拉霉素治疗慢性盆腔炎的疗效及对患者炎性因子和血液流变学指标的影响

目的:探讨桂枝茯苓胶囊联合克拉霉素治疗慢性盆腔炎的效果及对患者炎性因子和血液流变学影响。方法:选取2016年1月-2017年8月本院诊治的慢性盆腔炎(气滞血瘀型)患者80例,按照随机数字表法分为观察组和对照组,各40例。对照组单用克拉霉素治疗,观察组在对照组基础上联合桂枝茯苓胶囊治疗,均治疗4周。比较两组治疗前后超敏C反应蛋白(hypersensitive C-reactive protein,hs-CRP)、白介素-6(interleukin-6,IL-6)、纤维蛋白原(fibrinogen,Fib)和D-二聚体(D-dimer,D-D)水平,比较两组临床疗效。结果:治疗后,观察组hs-CRP、IL-6、Fib、D-D水平均低于对照组,比较差异均有统计学意义(P<0.05);观察组总有效率为92.50%(37/40),高于对照组的75.00%(30/40),比较差异有统计学意义(P<0.05)。结论:桂枝茯苓胶囊联合克拉霉素治疗慢性盆腔炎效果显著,可改善炎症反应,纠正高凝状态,值得推广。     

丁苯酞对急性脑梗死患者血清细胞因子、神经功能及血液流变学的影响

目的:分析丁苯酞应用于急性脑梗死的治疗,对患者神经功能、血清细胞因子和血液流变学指标的影响。方法:选取2015年1月-2017年1月本院收治的急性脑梗死患者95例。根据用药策略不同将其分为常规组(n=46)和试验组(n=49)。两组均行常规治疗,试验组在此基础上加用丁苯酞治疗,两组均以15 d为一疗程。观察两组治疗前后的白介素-6(Interleukin-6,IL-6)、高敏C反应蛋白(high sensitive-C reaction protein,hs-CRP)、红细胞比容、血浆黏度、美国国立卫生研究院卒中量表评分(National Institute of Health stroke scale,NIHSS)和格拉斯哥昏迷指数评分(Glasgow Coma Scale,GCS)。结果:治疗后,试验组hs-CRP、IL-6水平、红细胞比容、血浆黏度均低于治疗前及常规组,比较差异均有统计学意义(P<0.05);治疗后,试验组NIHSS评分为(5.71±1.05)分,均低于治疗前及常规组的(17.78±3.73)、(9.23±2.56)分,GCS评分为(12.51±1.73)分,均高于治疗前及常规组的(8.76±1.49)、(10.20±1.58)分,比较差异均有统计学意义(P<0.05)。结论:丁苯酞辅助常规疗法能有效改善急性脑梗死患者血清细胞因子表达水平,增强神经功能,促进血液流变学指标的恢复。     

粘弹流变体数学模型和等价模型的研究

本文首次提出用复元件来建立粘弹流变力学模型的拉氏状态方程的新方法,建立这种新数学模型较易于微分状态方程的建立。本文还提出流变力学模型的结构式表示法和计算法,用结构式来判别各种等价模型非常便捷。     

Modeling of Magneto-Rheological Damper with Neural Network

With the revival of magnetorheological technology research in the 1980＇s, its application in vehicles is increasingly focused on vibration suppression. Based on the importance of magnetorheological damper modeling, nonparametric modeling with neural network, which is a promising development in semi-active online control of vehicles with MR suspension, has been carried out in this study. A two layer neural network with 7 neurons in a hidden layer and 3 inputs and 1 output was established to simulate the behavior of MR damper at different excitation currents. In the neural network modeling, the damping force is a function of displacement, velocity and the applied current. A MR damper for vehicles is fabricated and tested by MTS; the data acquired are utilized for neural network training and validation. The application and validation show that the predicted forces of the neural network match well with the forces tested with a small variance, which demonstrates the effectiveness and precision of neural network modeling.     

Relationship between rheological manufacturing process and optical performance of optical fiber coupler

Through theoretical analysis and experiments, the viscoelastic mechanical model of optical fiber coupler in the process of fused biconical taper was established, and the numerical analysis in non-uniform temperature field was made. The results show that the rheological parameters, such as drawing speed and fused temperature, have a tremendous influence on stress distribution and performance of optical fiber coupler, especially the influence of fused temperature. The change of fused temperature by 5 ℃ can lead to the change of the maximum stress by 30% and stress difference by 20% in the same cross section. The change of temperature gradient by 3% can result in the change of stress difference by 90%. In the present condition of rheological technology, rheological defects such as crystallizations and microcracks are easy to generate in the optical fiber coupler.