奈非西坦药物的合成研究

以碳酸钠为缚酸剂,摩尔比为1︰1的2,6-二甲基苯胺与氯乙酰氯反应合成了中间体2-氯-N-(2,6-二甲基苯基)乙酰胺;在强碱乙醇钠作用下,2-吡咯烷酮再与2-氯-N-(2,6-二甲基苯基)乙酰胺经亲核取代合成了目标化合物奈非西坦。探讨了影响中间体和奈非西坦产率的因素,在乙醇钠、2-氯-N-(2,6-二甲基苯基)乙酰胺和2-吡咯烷酮的摩尔比为2︰1︰2、反应时间为2 h的较佳工艺条件下,产品总收率达81%。     

Recognizing control chart patterns with neural network and numerical fitting

Control chart has been widely used to determine whether the state of machining process is stable or not, and pattern recognition technology is often used to automatically judge the changing modes of control chart. It is because that the abnormal patterns of a control chart can reveal the potential problem of machining quality. In order to improve the recognition rate and efficiency of control chart patterns, a neural network-numerical fitting (NN-NF) model is proposed to recognize different control chart patterns. A back propagation (BP) network is first used to recognize control chart patterns preliminarily. And then, numerical fitting method is adopted to estimate the parameters and specific types of the patterns, which is different from the traditional neural network-based control chart pattern recognition methods. Based on this, Monte Carlo simulation is used to generate training and testing data samples. The results of simulated experiment show that training time of this NN-NF model can be reduced. At the same time, the recognition rate can also be improved. At last, a real example is also provided to illustrate the NN-NF model.     

基于自适应有限元法和改进遗传算法的边坡临界滑动面搜索

本文采用自适应有限元法进行边坡稳定分析,将改进的遗传算法和自适应有限元法相结合,建立基于应力场的边坡任意形状临界滑动面的全局搜索方法，该改进的遗传算法采用十进制编码,并根据个体适应度不同对交叉概率和变异概率进行自适应调整,使群体中的优良个体不易被破坏,同时又保证种群个体的多样性,从而提高算法的搜索效率.通过典型算例分析,证明这种基于自适应有限元分析和改进遗传算法的边坡任意形状临界滑动面搜索方法可行、高效。     

SPECT心肌灌注断层显像左心室的自动提取

通过分析ＳＰＥＣＴ心肌灌注断层图象的象素之几何分布,利用最小二乘法拟合心肌左心室的半球加圆柱模型,采用迭代算法去除非左心室组织显影,实现左心室的自动提取。该技术为进一步定量分析提供了基础。     

3t熔化炉烟气余热回收利用

先用换热器回收熔化炉的烟气余热来提高助燃空气温度，再直接利用经过换热器后的烟气来烘干铁砂，不仅能大幅度降低能耗，而且产品质量及生产能力都有很大提高，效果非常理想。     

掺饵光纤的优化设计

本文讨论了掺铒光纤放大器的应用前景，介绍了掺饵光纤的放大原理。用Ｅｒ３＋离子三能级模型进行了光纤参量的优化设计，并用ＭＣＶＤ工艺制备了性能优良的掺Ｅｒ—Ａｌ光纤。     

牵引逆变器IGBT风冷散热试验及仿真平台搭建

IGBT散热性能是影响高速动车组在行驶过程中安全性、可靠性及动力性的重要因素。本文以某出口铰接车牵引变流器箱为试验研究载体,研制了专用风冷散热试验台;同时运用仿真软件Flotherm进行了仿真计算,通过实物试验与仿真计算的对比研究,验证了仿真计算的可行性。     

Engineering 2D Mesoporous Silica@MXene‐Integrated 3D‐Printing Scaffolds for Combinatory Osteosarcoma Therapy and NO‐Augmented Bone Regeneration

The rising concerns of the recurrence and bone deficiency in surgical treatment of malignant bone tumors have raised an urgent need of the advance of multifunctional therapeutic platforms for efficient tumor therapy and bone regeneration. Herein, the construction of a multifunctional biomaterial system is reported by the integration of 2D Nb₂C MXene wrapped with S‐nitrosothiol (R? SNO)‐grafted mesoporous silica with 3D‐printing bioactive glass (BG) scaffolds (MBS). The near infrared (NIR)‐triggered photonic hyperthermia of MXene in the NIR‐II biowindow and precisely controlled nitric oxide (NO) release are coordinated for multitarget ablation of bone tumors to enhance localized osteosarcoma treatment. The in situ formed phosphorus and calcium components degraded from BG scaffold promote bone‐regeneration bioactivity, augmented by sufficient blood supply triggered by on‐demand NO release. The tunable NO generation plays a crucial role in sequential adjuvant tumor ablation, combinatory promotion of coupled vascularization, and bone regeneration. This study demonstrates a combinatory osteosarcoma ablation and a full osseous regeneration as enabled by the implantation of MBS. The design of multifunctional scaffolds with the specific features of controllable NO release, highly efficient photothermal conversion, and stimulatory bone regeneration provides an intriguing biomaterial platform for the diversified treatment of bone tumors.     

微小电感平面线圈的信号检测技术研究

平面线圈是一种被广泛应用的非接触测量探头,但线圈的电感值微小,一般只有1 μH,给信号提取和检测带来了困难.本文应用微分弛张振荡电路,对微小电感线圈的信号检测技术开展了研究.理论分析和实验结果表明,在合适的阻抗参数条件下,可以有效地提取平面线圈的微小电感变化信号,并保持较高的灵敏度和良好的稳定性.