复凝聚法制备农药微胶囊剂的研究

以壳聚糖和木质素磺酸钠为囊材,以三氟氯氰菊酯为囊芯,采用复凝聚法制备了微胶囊。考察了壳芯质量比、温度、搅拌速度、对包药率的影响,确定最佳工艺条件,并对其性能进行了研究。     

复相乳液法制备碳酸钠微胶囊的研究

采用复相乳液法,研制了以乙基纤维素为壁材,以碳酸钠为芯材的微胶囊化产品.结果表明:微胶囊化的最佳工艺参数为壁材溶液浓度为8%,保护剂溶液浓度为10%,搅拌速度为600 r/min,油相:水相为1:6.以乙基纤维素作为壁材制得的微胶囊化碳酸钠具有较高的产率.     

复相乳液法制备聚乳酸／胰岛素缓释微胶囊

探讨复相乳液法制备聚乳酸(PLA)/胰岛素缓释微胶囊的制备工艺. 以聚乳酸为包裹载体,胰岛素为模型药物,通过复相乳液法制备出胰岛素缓释微胶囊,通过考察稳定剂、超声时间及功率、搅拌速度、聚乳酸分子量等条件对粒径大小及其分布、表面形态的影响,初步探讨了聚乳酸包裹胰岛素微胶囊的制备工艺.经粒度分析仪、扫描电镜、激光共聚焦显微镜观察结果显示,制备的微胶囊表面光滑圆整,平均粒径在4 μm左右. 复相乳液法制备载药微球工艺简单,乳液稳定性好,可以负载具有生物活性的药物.     

复乳化(W/O/W)-复凝聚-喷雾干燥法制备维生素B_1微胶囊的研究

水溶性芯材包埋的方法复杂,包埋率较低。以明胶和阿拉伯胶为壁材,谷氨酰胺转氨酶作为封端基剂,采用复乳化(W/O/W)-复凝聚-喷雾干燥法制备维生素B_1微胶囊。研究结果表明:维生素B_1微胶囊外观呈球形,有典型凹陷,表面完整,囊壁的结构对芯材有良好的保护作用;红外图谱显示无新的化学键形成,表明明胶、阿拉伯胶是通过静电相互作用形成胶囊;玻璃化转变温度为50.77℃,在室温25℃时贮藏性质较稳定;D50粒径是8.83μm;微胶囊产品的包埋率为91.84%,复乳化(W/O/W)-复凝聚-喷雾干燥法能用于水溶性芯材的包埋。     

玻璃纤维／环氧树脂纺织复合材料水分散法制备

本文初步探索了玻璃布增强环氧树脂复合材料的水分散法制备工艺,研究了玻璃布的浸渍工艺,并通过对材料力学性能的测试,探索了最佳模压成型工艺参数。结果表明：浸渍液浓度应较高,浸渍时间为40秒左右,浸渍次数为4～5次;复合材料制备较佳的工艺参数为模压压力12MPa、模压时间6min和模压温度190℃。     

微胶囊-纤维水泥基复合材料的动态压缩性能

微胶囊自修复水泥基材料具有良好的修复性能,但力学性能会随着微胶囊的加入有所减弱．纤维的加入可以增强材料的裂缝效果,与微胶囊形成有效互补．为研究纤维类型和应变率对微胶囊自修复水泥基材料压缩性能的影响,设计3种配合比类型,即聚乙烯醇(polyvinyl alcohol,PVA)纤维、聚酰胺(polyamide,PA)纤维及PVA-PA混杂纤维的实验试件,基于立方体抗压实验系统及分离式霍普金森压杆装置(split Hopkinson pressure bar,SHPB),研究不同应变率下的动态压缩行为．研究结果表明,在应变率为1×10^-5s^-1时,加入PVA、PA和PVA-PA后,自修复水泥基材料的压缩强度分别下降了12.96%、8.91%和9.03%;随着应变率的提高,材料的压缩强度不断增大,且材料的动态增长因子与应变率满足线性关系;在低应变率下,纤维能改善材料的能量吸收能力,耗散能及能量耗散因子有所提高．研究可为混凝土材料在动态条件下提高自修复性能提供实验依据．     

复相乳液法中药微胶囊的制备与性能研究

研究了采用复相乳液法制备抗菌抗病毒微胶囊的技术,并对制得的胶囊进行了性能测试和分析．测试结果表明：在优化条件下制得的微胶囊的粒度为0．4μm左右,比一般工艺制得的胶囊粒度小．将胶囊整理到织物上进行缓释性测试,在100天内微胶囊的释放率仅为45％,体现了胶囊小粒径的优越性．     

无机材料对沥青-环氧树脂复合材料的性能影响

采用XRD、IR、SEM等测试技术,研究了硅酸盐水泥(SAC)、硫铝酸盐水泥(PC)、熟石灰(CH)、磨细石灰石粉(LS)对乳化沥青和水性环氧树脂组成的复合胶浆匀质性和稳定性的影响机制。结果表明:SAC、PC、CH对复合胶浆匀质性和稳定性均有提升作用,其效果依次为SAC>PC>CH,而LS对胶浆的匀质性、稳定性无改善作用,PC和SAC可作为乳化沥青-水性环氧树脂制备复合材料的结构稳定增强介质,使不相容的沥青(非极性)和环氧树脂(极性)胶结形成稳定的互穿网络结构,提高复合材料的物理力学性能和耐久性能。     

微胶囊-纤维水泥基复合材料动态劈裂拉伸性能研究

采用 Φ120 mm分离式霍普金森压杆(Split Hopkinson Press Bar,SHPB)试验装置进行巴西圆盘劈裂试验,研究在应变率范围0.96～30.30 s-1微胶囊-纤维水泥基复合材料的应变率敏感性和破坏规律.试验结果表明,水泥基复合材料具有明显的应变率效应,其劈裂抗拉强度随着应变率的增加而提高,掺入聚乙烯醇(P V A)-聚乙烯(P E)混杂纤维时水泥基复合材料劈裂抗拉强度最高.在动态荷载作用下,掺入纤维不仅能有效抑制基体微裂纹的萌生和降低扩展速度,而且能改善微胶囊自修复混凝土的抗冲击韧性.     

氧化石墨烯-多壁碳纳米管/环氧树脂复合材料力学性能研究

通过对原始多壁碳纳米管进行功能化处理,得到了羧基功能化的多壁碳纳米管,并利用改进的Hummers法制备了氧化石墨烯,通过扫描电子显微镜和透射电子显微镜分别对它们的形貌进行了观察.研究了在环氧树脂中加入多壁碳纳米管和氧化石墨烯总质量分数为0. 1%的前提下,不同比例的多壁碳纳米管与氧化石墨烯对环氧树脂纳米复合材料力学性能的影响.结果显示,氧化石墨烯和多壁碳纳米管确实能够改善环氧树脂复合材料的拉伸强度、弯曲强度、弯曲模量、储能模量等力学性能,氧化石墨烯对于复合材料拉伸性能的提高要优于多壁碳纳米管,而多壁碳纳米管对复合材料弯曲性能的改善要优于氧化石墨烯.     

最大化阵列效率的方向图综合方法

基于自适应阵列理论和模板逼近的方向图综合方法常强调方向图形状的控制,而往往忽略了阵列的效率．针对此问题,提出了方向图形状约束下,最大化阵列效率的方向图综合方法．该算法以空域匹配权模值最小为目标函数,以主副比、3dB宽度、主瓣平顶或干扰陷零等为约束条件,优化出最优权,在保证方向图形状的同时兼顾了阵列效率．计算机仿真验证了该方法的有效性和优越性．     

基于Cobb-Douglas生产函数的分配效率测算方法

由于收集数据时很难获取投入要素的价格信息,因此在实际分析生产效率时很难使用分配效率这一重要指标.本文在假设经济无效完全是由技术无效造成的前提下,利用Cobb-Douglas生产函数与成本函数的自对偶性,通过分析Cobb-Douglas型技术效率与经济效率之间的关系,得到了分配效率的测算公式.这个测算公式与投入价格无关,仅仅是技术效率的一个函数.对我国20个行业分配效率和技术效率的测算结果表明:我国工业各部门的资源配置能力相对较强,但获取最大产出的能力较弱.     

含矿物油废水超滤法处理的实验研究

用超滤法对含矿物油废水进行了实验研究分析及比较。结果表明：聚醚砚膜PES-200适用于处理该种废水。洗洗后膜的通量可恢复到95%。     

潜航员认知效能驱动的作业舒适度评价方法

舒适的作业环境是人员高水平作业能力维持的重要保障,为实现载人潜水器舱室操作系统作业舒适度的定量评价,依据载人潜水器操作系统中显控界面、操作面板和通讯设备3个子系统的舒适性特征,提出潜航员认知效能驱动的载人潜水器舱室操作系统作业舒适度评价方法。该方法基于潜航员作业实际,分析潜航员认知流程,形成潜航员认知表现-效能-舒适度对应关系;依托操作系统作业舒适度实验数据,运用效用函数构建潜航员认知效能模型;采用支持向量机模型综合考虑子系统特征属性以及潜航员认知效能、年龄、学历等因素对子系统作业舒适度感知的影响;结合专家权重调查法,实现子系统作业舒适度耦合,确定操作系统作业舒适度。结果表明：当显控界面亮度、对比度和自然饱和度分别界于[-25,0],[-50,-25],[-25,0]范围,操作面板设计具有合理的布局参数和待布区形心相对位置,以及通讯设备中环境噪声频率较低和通信语音采样频率为48 000 Hz时,操作系统具有较高的舒适度。本研究表明,潜航员认知效能与主观舒适度具有相同的变化趋势,基于潜航员认知效能判断舱室操作系统作业舒适度的方法可行。     

PCF纤维过滤工艺用于超滤前处理的研究

差4倍多. ︵几·邻日·已、啊叫戮 近年来，随着水资源短缺状况的日益严重和国家 对节水要求的日益提高，污水与废水的资源化处理回 用成为缓解矛盾的重要途径〔’〕.膜分离技术在许多领 域的工业废水处理和回用中己逐渐普及并广为应用， 电力、化工、石油、冶金等行业已经成功     

Synthesis and characterization of ibuprofen-rectorite composites by solution intercalation method

The ibuprofen-rectorite composites were prepared by the solution intercalation method using ibuprofen and rectorite as raw materials, and were characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared analysis and scanning electron microscopy (SEM). The experimental results show that the ibuprofen is intercalated into the interlayer spaces of rectorite. The values of the (001) peaks of the ibuprofen-rectorite composite are larger than that of Na-rectorite and reach the largest when the reaction time and ibuprofen amount is 2 h and 0.36 g, respectively. The layered structure of Na-rectorite is destroyed to some extent with the intercalation of ibuprofen into the interlayer space in the structure of Na-rectorite. A part of ibuprofen in the ibuprofen Na-rectorite covers on the surface of Na-rectorite besides some ibuprofen enters into the interlayer space. Funded by the Program for New Century Excellent Talents in University (NCET05-0662)     

Application research on self-healing technology with microcapsules for automobile brake pad

In order to improve the performance of non-asbestos composite auto brake pads that are composed of matrix resin, reinforced material and fillers, a novel method with new technology of self-heal microcapsules was proposed. Nano reinforced fillers’ effects were also considered in the experiment project. Five recipe designs for new composite auto brake pads were carried out and corresponding samples were prepared as well. The friction coefficient and wearing properties at certain temperature, impact intensity and hardness were comparatively studied. Investigations indicate that properties of such composite auto brake pads meet the requirements of the national standards while microcapsule’s weight content varies from 5.5wt%–1.09wt% of matrix resin and microcapsule’s location varies in the pads. Nano reinforced fillers have the effects of increasing composites’ impact intensity and hardness. Application of self-healing microcapsules in auto brake pads is feasible. Funded by the Beijing Talent and Innovation Project (No. 2006)     

Investigation on the thermal conductivity of HDPE/MWCNT composites by laser pulse method

Thermal conductivity (TC) of high density polyethylene/multiwall carbon nanotube (HDPE/MWCNT) composite films was measured by laser pulse method. It is found that the TC increased quickly with the increase of MWCNT fraction when the volume fraction of MWCNT was below 3.35%. However, as the volume fraction of MWCNT was over 3.35%, the increasing rate became slow. A new percolation model was proposed based on the effect of MWCNT network to simulate the TC of HDPE/MWCNT composite films. The simulation result was in good agreement the experimental data well. In addition, the relationship of TC with the increase of temperature was also discussed. Supported by the National Natural Science Foundation of China (Grant No. 90606008 and 50706057)     

Network-level optimization method for road network maintenance programming based on network efficiency

To maintain their capacity,transportation infrastructures are in need of regular maintenance and rehabilitation.The major challenge facing transportation engineers is the network-level policies to maintain the deteriorating roads at an acceptable level of serviceability.In this work,a quantitative transportation network efficiency measure is presented and then how to determine optimally network-level road maintenance policy depending on the road importance to the network performance has been demonstrated.The examples show that the different roads should be set different maintenance time points in terms of the retention capacities of the roads,because the different roads play different roles in network and have different important degrees to the network performance.This network-level road maintenance optimization method could not only save lots of infrastructure investments,but also ensure the service level of the existing transportation system.