轻工学术型研究生科研思维与能力提升途径的探讨

如何提高学术型研究生的科研思维与科研能力一直是研究生培养的重要和关键问题,文章分析了目前我国轻工技术与工程学术型研究生培养的现状,指出缺乏系统的培养方式和体系是其关键所在,并指出更新知识结构,建设创新型课程体系以及理论和动手实践相结合的学习体系,辅以创新的学习方法和手段,才能有效地提高研究生的创新能力.     

沥青道路冷再生系统中水泥基胶结效应

设定不同配比的再生沥青混合料(RAP)和不同水泥掺量,通过标准击实、无侧限抗压强度、水稳定性、模量性能以及SEM测试,研究了水泥在RAP中的胶结效应。结果表明:RAP中沥青含量与稳定土的质量比(A/S)为0.4时,随着水泥掺量的增大,RAP的最大干密度从1.91 g/cm3增加到2.00 g/cm3。水泥掺量一定时,随着废旧沥青含量的增加,RAP的最大干密度随随之增大;掺6%水泥的RAP无侧限抗压强度从1.48 MPa增加到2.63 MPa,随之减小到2.28 MPa。使用的材料体系中,A/S=0.4,掺6%水泥,用水量9.5%时,再生料获得最好性能。试件浸水后抗压强度普遍降低,但与干燥试件无侧限抗压强度变化趋势一致。对RAP的模量试验表明高温状态下RAP混合料的路用性能最差。SEM测试表明:水泥的水化使得混合料中有针状钙矾石和纤维状C-S-H凝胶相互交织搭接,形成网络结构,将集料颗粒包裹起来,这是RAP产生强度的主要因素。     

以聚四氟乙烯乳胶粒子为种子的丙烯腈/苯乙烯乳液共聚合

以工业聚四氟乙烯(PTFE)乳胶粒子为种子,进行苯乙烯/丙烯腈(St/AN)种子乳液聚合,研究了单体加入方式、OP-10和十二烷基硫酸钠(SDS)复合乳化剂组成和用量对聚合稳定性、复合乳胶粒子平均粒径及粒径分布和形态的影响。结果表明,单体预乳化半连续乳液聚合稳定性高于间歇乳液聚合,两者又高于单体未乳化半连续乳液聚合;当OP-10/SDS复合乳化剂(OP-10/SDS质量比为2～1/2)用量小于4%质量分率时,采用间歇和半连续乳液聚合得到的复合乳胶粒子的平均粒径均大于PTFE种子;当复合乳化剂用量大于4%质量分率时,复合乳胶粒子平均粒径小于PTFE种子,与St/AN共聚物(SAN)二次粒子形成有关。PTFE粒子呈棒状或鹅卵状,而种子间歇乳液聚合和单体预乳化半连续乳液聚合得到的PTFE-SAN复合粒子均呈球状,PTFE被SAN包覆较完全。     

铁钛结晶釉的制备

以钾长石、石英、石灰石、滑石、骨灰、氧化铁、氧化钛为主要原料试制出了钛铁结晶釉。从配方及工艺着手,通过单因素试验法探讨了配方组成及工艺因素对钛铁结晶釉性能的影响。     

浅谈分置式防空系统中弹炮结合问题

本文针对分置式弹炮结合防空系统设计和使用,讨论了有关武器选择、阵地布置、攻击区划分、多目标分配、弹炮协同作战以及如何避免弹、炮间相互影响等问题。     

阻焊塞孔工艺改善

通过改良阻焊塞孔工具、规范网印塞孔操作、修改后固化参数,改善公司阻焊塞孔质量不稳定的问题。     

辫群上新的签名体制

 辫群是构造抗量子攻击密码协议的新平台。该文基于辫群上求根问题的难解性提出了新的签名体制,并证明其在随机预言模型下能抵抗适应性选择消息的存在性伪造攻击。新体制在签名验证阶段不需要判断辫元是否存在共轭关系,计算效率比共轭签名体制、改进共轭签名体制更高;签名由一个整数和一个辫元组成,与共轭签名体制相比长度更短,与改进共轭签名体制长度相当。     

污水集中排放监控终端的设计和实现

设计了一套针对污水处理厂的排污企业污水排放监控系统。主要监测其排放污水的实时流量、流速等现场数据。采用485通信、无线DTU传输、因特网接入等多种通信方式,解决了远程现场环境下的数据传输问题,实现了污水排放现场数据实时上传和排污现场控制功能。     

Synthesis and characterization of fluorine‐containing liquid crystalline polysiloxanes bearing cholesteryl cinnamate mesogens and trifluoromethyl‐substituted mesogens

Several novel side‐chain liquid crystalline (LC) polysiloxanes bearing cholesteryl cinnamate mesogens and trifluoromethyl‐substituted mesogens were synthesized by a one‐step hydrosilylation reaction with poly(methylhydrogeno)siloxane, a cholesteric LC monomer cholesteryl 3‐(4‐allyloxy‐phenyl)‐acryloate and a fluoro‐containing LC monomer 4‐[2‐(3‐trifluoromethyl‐phenoxy)‐acetoxy]‐phenyl 4‐allyloxy‐benzoate. The chemical structures and LC properties of the monomers and polymers were characterized by use of various experimental techniques, such as FTIR, ¹H‐NMR, ¹³C‐NMR, TGA, DSC, POM, and XRD. The temperatures at which 5% weight loss occurred were greater than 300°C for all the polymers, and the residue weight near 600°C increased slightly with increase of the trifluoromethyl‐substituted mesogens in the fluorinated polymer systems. The samples containing mainly cholesteryl cinnamate mesogens showed chiral nematic phase when they were heated and cooled, but the samples containing more trifluoromethyl‐substituted mesogens exhibited chiral smectic A mesophase. The glass transition temperature of the series of polymers increased slightly with increase of trifluoromethyl‐substituted mesogens in the polymer systems, but mesophase–isotropic phase transition temperature did not change greatly. In XRD curves, the intensity of sharp reflections at low angle increased with increase of trifluoromethyl‐substituted mesogens in the fluorinated polymers systems, indicating that the smectic order derived from trifluoromethyl‐substituted mesogens should be strengthened. These results should be due to the fluorophobic effect between trifluoromethyl‐substituted mesogens and the polymer matrix. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Numerical study of particle motion pattern in a rotating wavy tumbler based on angular momentum analysis

This work uses the hard-sphere model to simulate the particle motion pattern in a two-dimensional rotating tumbler with a sine-wave boundary. Based on the angular momentum analysis, the present work investigates the intrinsic effects of boundary configuration of tumblers, e.g. the wave number and the boundary amplitude, on the motion pattern of the particles separately. It is found that the particle motion pattern depends on the configuration of the tumbler significantly. There are two collision patterns, namely the primary and secondary patterns. The former pattern dominates when the boundary is composed of low wave numbers or small boundary amplitudes, whereas the latter pattern dominates when the boundary is composed of high wave numbers or large boundary amplitudes. The primary collision pattern is beneficial for the bulk motion of tumbling of the particle clusters, whereas the secondary pattern suppresses it. The interpretation for the different mechanisms of collision pattern indicates the existence of different regions, which is either positive or negative to the tumbling motion. It provides some guiding information for engineering application, such as the design of tumblers for efficient mixing.