一种可扩展网格监控系统的设计与实现

基于网格服务架构中的网格服务和网格信息服务,提出了一种新的系统结构来构建网格监控系统,给出了它的一个原型系统实现。该结构采用了网格服务调用的方法,借鉴了层次化监控模型和GMA监控模型的特点,具备良好适应性和可扩展性。多种监控信息获取机制的使用适应了不同的监控需求,使监控系统在实现上更具灵活性和可靠性。     

甲基丙烯酸甘油酯改性大豆蛋白胶黏剂的制备及热压工艺优化的研究

以过硫酸铵/亚硫酸氢钠(APS/NaHSO3)氧化还原剂为引发体系,由疏水性甲基丙烯酸缩水甘油酯(GMA)和尿素改性大豆蛋白,在50℃下进行乳液聚合反应,得到了甲基丙烯酸缩水甘油酯接枝大豆蛋白胶黏剂(GSP)。考察了胶黏剂的稳定性、表观黏度以及胶黏剂胶黏强度和耐水性的影响因素及热压工艺条件。     

GMA-DSP测控系统的PID控制设计与实现

设计了一种用于精密定位控制的超磁致伸缩微位移驱动器(GMA),介绍了其结构及工作原理,并构建了以DSP处理芯片TMS320F2812为控制核心的GMA位移闭环控制系统,在实验辨识系统控制对象模型的基础上,设计了PID控制调节器,经实验测试,成功实现了输出位移的高稳定、高精度自动控制,为GMA在高精控制领域的实际应用奠定了基础。     

Effect of polyhedral oligomeric silsesquioxane on water sorption and surface property of Bis‐GMA/TEGDMa composites

2,2‐Bis[4‐(2‐hydroxy‐3‐methacryloxypropoxy)phenyl]propane (Bis‐GMA), one of the most important light‐curable dimethacrylate resins, is widely used as dental restorative material. However, one problem of Bis‐GMA is the high water sorption due to the hydrophilic hydroxyl (–OH) group, resulting in a short life in actual application. In this study, to overcome the drawback stated above, novel organic–inorganic dimethacrylate monomer containing polyhedral oligomeric silsesquioxanes (POSS), Bis‐GMA‐graft‐POSS, is synthesized via the nucleophilic addition reaction of isocyanate functionalized POSS (IPOSS) and pendent hydroxyl group of Bis‐GMA. Then the as‐synthesized Bis‐GMA‐graft‐POSS, of which hydroxyl group was substituted by hydrophobic POSS, is also introduced into the Bis‐GMA/TEGDMA matrix to prepare a series of methacrylate‐based hybrids for dental materials under visible light with camphorquinone and ethyl‐4N,N‐dimethy‐laminobenzoae (EDMAB) as initiator and coinitiator, respectively. Compared to Bis‐GMA/TEGDMA composites, water sorption of modified composites can be significantly reduced with the addition of Bis‐GMA‐graft‐POSS. Moreover, the Bis‐GMA/TEGDMA/POSS hybrids show hydrophobic surfaces, leading to much higher water contact angles than that of Bis‐GMA/TEGDMA composites. The morphology of hybrids containing POSS was furthermore studied by X‐ray diffraction (XRD) analysis and X‐ray photoelectron spectroscopy (XPS). The results show that POSS disperses in the matrix in noncrystalline form and tend to migrate to the surface of the modified composites that lead to the lower water sorption and higher water contact angles. These results are very useful for design of novel methacrylate monomers and clinical application. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Complex polymer architectures via RAFT polymerization: From fundamental process to extending the scope using click chemistry and nature's building blocks

Reversible addition fragmentation chain transfer (RAFT) polymerization has made a huge impact in macromolecular design. The first block copolymers were described early on, followed by star polymers and then graft polymers. In the last five years, the types of architectures available have become more and more complex. Star and graft polymers now have block structures within their branches, or a range of different branches can be found growing from one core or backbone. Even the synthesis of hyperbranched polymers can be positively influenced by RAFT polymerization, allowing end group control or control over the branching density. The creative combination of RAFT polymerization with other polymerization techniques, such as ATRP or ring-opening polymerization, has extended the array of available architectures. In addition, dendrimers were incorporated either as star core or endfunctionalities. A range of synthetic chemistry pathways have been utilized and combined with polymer chemistry, pathways such as ‘click chemistry’. These combinations have allowed the creation of novel structures. RAFT processes have been combined with natural polymers and other naturally occurring building blocks, including carbohydrates, polysaccharides, cyclodextrins, proteins and peptides. The result from the intertwining of natural and synthetic materials has resulted in the formation of hybrid biopolymers. Following these developments over the last few years, it is remarkable to see that RAFT polymerization has grown from a lab curiosity to a polymerization tool that is now been used with confidence in material design. Most of the described synthetic procedures in the literature in recent years, which incorporate RAFT polymerization, have been undertaken in order to design advanced materials.     

用于水性工业涂料的苯丙型耐盐雾乳液的合成

采用预乳液半连续滴加工艺,以阴非离子复合乳化剂为乳化体系进行乳液聚合,得到Tg为40℃,黏度为200~500 mPa.s,固含量为45%的苯丙乳液。此乳液以丙烯酰胺为交联单体,并以环氧单体、含氟单体联合改性,研究了两种特殊单体用量对乳液耐盐雾性能的影响。结果表明,当环氧单体甲基丙烯酸缩水甘油酯(GMA)用量为总单体用量(质量分数)的4.4%,含氟单体用量为总单体用量(质量分数)的1.0%时,能够显著提高乳液的交联度和疏水性,乳液成膜后进行中性盐雾实验,中性盐雾时间可达到240 h,板面无锈点,主体无起泡。此种耐盐雾乳液可专门用于水性工业涂料的调配,能够显著提高涂料的耐盐雾性能。     

基于亲和度的引力移动算法

为提高引力移动算法搜索性能，针对引力移动算法解决一些高维空间优化问题时存在的收敛速度慢、搜索精度不高的问题，提出一种基于亲和度的改进引力移动算法PGMA。基于引力移动算法原理，通过构造一个基于亲和度概念的系数对种群个体受到的引力合力公式作适当的变换改造基本引力移动算法。改进后的算法对种群中个体的位置更新方向加以引导，来提高算法的搜索精度和算法搜索能力。用13个基准函数对改进算法进行试验验证改进算法在求解精度和稳定性上优于基本引力移动算法。     

超磁致伸缩微致动器车削系统建模与控制

综合考虑温度、预应力及碟簧非线性的影响,建立超磁致伸缩微致动器(giant magnetostri ctive micro actuator,简称GMA)车削加工系统非线性动力学微分方程。根据精确反馈线性化的滑模变结构控制方法设计控制器,采用双曲正切函数代替符号函数,并引进边界层,减少了系统的抖振,增加控制器的连续性。最后通过试验,验证了该控制方法的有效性,当系统存在外界干扰或是参数摄动时,该文设计的控制方法都能取得较好的控制效果,稳态误差达到纳米级。     

基于GMA再生型车削颤振抑制系统实验研究

切削颤振是金属加工时刀具和工件之间的一种复杂且有害的强烈相对振动。文章从理论上分析了再生型颤振的机理,建立超磁致伸缩致动器( GMA)颤振系统动力学模型,并阐述了超磁致伸缩微致动器颤振系统的稳定性,最终通过对比切削颤振实验和颤振抑制实验的振动信号数据结果,验证了基于GMA的颤振抑制系统抑制切削颤振的可行性。     

分散聚合法制备环氧基磁性复合微球

采用化学共沉淀法制备了油酸包覆的Fe3O4磁性纳米粒子,以此为核·采用分散聚合法制备了表面带有环氧基团的Fe3O4／聚甲基丙烯酸缩水甘油酯（PGMA）磁性复合微球,探讨了聚合工艺、聚合条件对甲基丙烯酸缩水甘油酯（GMA）利用效率的影响规律,并用傅立叶变换红外光谱仪（FTIR）、热重分析仪（TGA）、振动样品磁强计（VSM）和扫描电镜（SEM）等对磁性复合微球的结构、磁性能和包覆量进行了表征．采用盐酸一丙酮法测定了磁性复合微球表面环氧基的含量。结果表明,在优化的条件下。GMA利用效率高达61．26％。磁性复合微球具有良好的单分散性·粒径为1～2μm．具有超顺磁性．比饱和磁强度为17．12emu·g^-1。环氧基含量达3．5mmol·g^-1。