原位复合纳米SiO2改性脲醛木塑复合材料制备

以原位复合纳米SiO2改性脲醛树脂为填充体，人工速生杨木为基体，通过真空加压浸渍法制得木塑复合材料。各种木塑复合材料的主要性能——增重率、抗吸水性、顺纹和恒纹压缩强度分别提高49％、38％、68％和83％。扫描电镜照片显示纳米SiO2改性脲醛完整地填充在杨木基体导管以及孔状结构中。傅立叶红外光谱（FTIR）分析纳米SiO2改性脲醛与杨木基体的固化反应表明，木塑复合材料中木质素C=O吸收峰1750cm^-1完全消失，木质素COO-吸收峰1645cm^-1增强而且发生偏移，充分证明纳米SiO2改性脲醛树脂填充体与木材基体之间发生了化学键合作用而使木塑复合材料各项力学性能得以增强。     

镁盐晶须原位复合酚醛泡沫制备及其性能研究

采用原位复合方法制备了镁盐晶须／酚醛泡沫复合材料，研究了镁盐晶须对泡沫粉化程度、回弹性以及力学性能的影响，并通过热失重和氧指数分析了镁盐晶须／酚醛泡沫复合材料的热稳定性和阻燃性。结果表明：少量镁盐晶须与酚醛泡沫复合，泡沫压缩强度、弯曲力均有明显的提高，特别是经偶联剂处理过的镁盐晶须，增强效果更好；当镁盐晶须含量为3％时，泡沫粉化程度和回弹性改善达到最优值；而且复合泡沫在高温区域的热稳定性也得到了改善，阻燃性有所提高。     

Cu-20%W原位复合粉末的制备工艺

采用原位化学共沉淀法,高温下加入Na2CO3精确控制前驱体粉末CuWO4×Cux(OH)yCO3的组成,再经二段氢还原工艺制备Cu-20%W复合粉末,对其形貌、物相组成、元素及粒度分布进行了表征. 结果表明,在原位反应液pH=5、温度75℃及(NH4)2WO4/Na2CO3摩尔比1/10.578、反应液总体积300 mL条件下,所得前驱体为CuWO4与Cu4(OH)6CO3组成的浅绿色络合物,合金元素收率高于95%;经450℃下0.5 h和600℃下0.5 h二段氢还原,得到粒径400~800 nm的亚微米级圆球状Cu-20%W复合粉末,钨半包覆铜且两相均匀分布.     

复合剪切力场下纳米SiO_2的制备及原位改性

以工业硅酸钠为前驱物、盐酸为沉淀剂、聚乙二醇为表面活性剂、硅烷偶联剂为改性剂,在复合剪切力场下,用化学沉淀法制备纯纳米二氧化硅(SiO2)和原位改性纳米SiO2,并进行放大实验。分析复合剪切力场下纳米SiO2的形成过程以及不同剪切力场、进料方式等对纳米SiO2型貌的影响。用Fourier红外光谱、透视电子显微镜、热重分析及粒径分析仪等对产品进行表征,结果表明:在复合剪切力场下制备的纳米SiO2的形貌近似为球形、平均粒径为19.5nm且粒径分布窄,原位改性纳米SiO2的分散效果良好。     

原位界面聚合制备PVDF复合纳滤膜的研究

为改善聚偏氟乙烯(PVDF)复合纳滤膜性能，以掺入单体哌嗪(PIP)的铸膜液制备基膜，通过原位界面聚合快速制备复合纳滤膜，简化了制备程序。ATR-FTIR分析结果表明，基膜上成功生成聚酰胺(PA)层，SEM观察到PA层表面具有典型结节结构。得到的复合纳滤膜对Na₂SO₄截留率为95.59%,渗透通量为12.37 L/(m²·h·bar),远高于传统界面聚合制备的PVDF复合纳滤膜。72 h的持续测试结果表明该复合纳滤膜具有良好的长期稳定性。     

原位复合法制备磁性纤维素纤维及其性能研究

以天然棉纤维为基材,用原位复合法在上沉积磁性Fe3O4纳米粒子,制备出磁性纤维素纤维,利用X射线衍射仪、傅立叶变换红外光谱仪、扫描电子显微镜等方法对所得产物中磁性粒子进行表征。探究了预处理方法以及铁离子（Fe^3＋/Fe^2＋=2）浓度对制得的纤维磁性能的影响,并对磁性纳米粒子与纤维的结合牢度进行了讨论。结果表明：两个因素均会对纤维的磁性能产生影响,当用5%Na OH处理棉纤维原料,在铁离子总浓度为0.10 mol/L（Fe^3＋/Fe^2＋=2）反应时,最有利于磁性纳米颗粒在其表面的沉积,制得棉纤维复合材料的磁性能可以达到11.90 eum/g;经多次洗涤后磁性纤维的磁性能稍有下降,说明磁性纳米粒子对纤维附着力较好,期望被用作功能材料。     

复合催化剂对玉米秸秆的原位催化热解研究

选用Fe_2O_3-CaO(Fe-Ca)和Fe_2O_3-Na_2CO_3(Fe-Na)2种廉价复合物质作为添加剂,以不同热解终温和添加剂配比作为影响因素,对玉米秸秆粉末原位催化热解特性进行研究。实验研究表明:玉米秸秆粉末热解焦油产率Fe-Na复合物添加后对玉米秸秆液相产物降解的催化作用强于Fe-Ca复合,Fe-Na复合型催化剂对液相产物具有较好的催化降解作用,产气率得到明显提升。Fe-Na质量配比对玉米秸秆热解具有影响,随着Na配比量增加玉米秸秆的原位催化热解作用先增强后减弱,在w(Fe∶Na)=5∶5时原位催化作用最强。Fe_2O_3在Fe-Ca和Fe-Na 2种复合催化剂中的作用效果不同,前者削弱Ca基催化焦油裂解重整生成芳香焦炭的能力,后者中促进Na基对焦油的裂解重整效果。     

乳液复合微粒的形态及其热力学预测

介绍了乳液复合微粒的形态结构，并对其形成的影响因素从加料方式，单体亲水性，引发剂，热力学和动力学等方面作了总结；对乳液复合微粒形态的热力学预测方法进行了评述，对乳液复合微粒形态的设计进行了概括。     

聚吡咯／粘胶导电复合纤维的原位聚合法制备

用较简便的液相原位聚合法制备了聚吡咯／粘胶导电复合纤维、讨论了吡咯、氧化剂和介质酸浓度、反应温度和反应时间对纤维导电性能的影响,并采用气相色谱法研究了吡咯聚合反应动力学。结果表明,该导电复合纤维具有良好的导电性、力学性能和环境稳定性,扫描电（ＳＥＭ）结果表明聚吡咯均匀地复合在每单根纤维上。     

原位复合成纤增强技术

介绍了2类原位复合成纤增强体系，分别讨论了它们的成纤机理，影响成纤的条件及组分间的相互影响；并概要地叙述了目前国内外在这些领域内所取得的进展。     

Thermodynamical analysis of the hydrogel state in poly(2-hydroxyethyl acrylate)

The thermodynamical properties of water and polymer in a hydrogel are analyzed from experimental equilibrium sorption isotherms at different temperatures in the case of poly(2-hydroxyethyl acrylate). The equations of the thermodynamics of mixtures allow to calculate the specific partial thermodynamical properties of water and polymer in the hydrogel as a function of its water content. Partial volume of water in the gel at low activities is slightly lower than the specific volume of water in the liquid state. The partial enthalpy and entropy differ significantly from those of pure water at the lowest water contents, and tend to those of pure water for activities close to one. The mutual interaction between the gel's components is discussed through the residual part of the mixing free energy. This function is positive for all gel compositions, suggesting that, on the average, the water-polymer interactions are not stronger than the water-water or polymer-polymer interactions, and that the affinity of water to mix homogeneously with the polymer has a combinatorial origin. The composition dependence of the Flory-Huggins interaction parameter is calculated and explained in terms on the residual free energy. This parameter is compared with the apparent interaction parameter, obtained fitting point by point the experimental sorption isotherm to the Flory-Huggins isotherm. The difference often found between the sorption capacity of an hydrogel when equilibrated in saturated water vapour and in liquid water is discussed.     

原位聚合法制备聚α-烯烃减阻剂微囊的工艺研究

以聚α-烯烃为囊心,以水和阴离子表面活性剂为分散系统、聚脲甲醛为壁材,采用原位聚合法制备出性能稳定的聚α-烯烃减阻剂微胶囊。利用红外光谱(IR)、扫描电镜(SEM)对微胶囊进行表征,对合成工艺参数进行了优化。结果表明,优化工艺为:尿素与甲醛的摩尔比为1∶2,聚脲甲醛壁材的加入量为10%,表面活性剂量为水量的0.5%,聚α-烯烃减阻剂粉粹至90¹00目,用硫酸调节体系的pH为3,60℃反应2 h。制备的α-烯烃聚脲甲醛微胶囊的表观形貌得到了有效的改善、减阻性能及存储稳定性优异。     

金红石加碳氯化的热力学

运用HSC软件对金红石构成的多元、多相、多反应的复杂体系进行还原平衡组分的计算与分析。通过热力学计算,所得的结果表明：金红石在200℃的较低温条件下可完全转化。金红石加碳氯化反应随着温度的升高和配碳量的增加,体系中CO／CO2摩尔比值增大。只要维持理论配碳量和氯气用量,金红石即可完全转化。     

原位聚合法制备聚α-烯烃减阻剂微囊的工艺研究

以聚α-烯烃为囊心,以水和阴离子表面活性剂为分散系统、聚脲甲醛为壁材,采用原位聚合法制备出性能稳定的聚α-烯烃减阻剂微胶囊。利用红外光谱(IR)、扫描电镜(SEM)对微胶囊进行表征,对合成工艺参数进行了优化。结果表明,优化工艺为:尿素与甲醛的摩尔比为1∶2,聚脲甲醛壁材的加入量为10%,表面活性剂量为水量的0.5%,聚α-烯烃减阻剂粉粹至90~100目,用硫酸调节体系的pH为3,60℃反应2 h。制备的α-烯烃聚脲甲醛微胶囊的表观形貌得到了有效的改善、减阻性能及存储稳定性优异。     

华恒选煤厂煤泥浮选的可行性研究

针对华恒选煤厂选煤方式单一、煤泥回收困难等问题,通过筛分试验、标准分步释放试验和煤泥浮选试验验证煤泥浮选的可行性。结果表明:煤泥中+0.5 mm产率较低,为0.18%,-0.25 mm产率为99.23%,符合煤泥浮选入料粒度要求;轻柴油和GF质量比9∶1,药剂用量为1000 g/t时,煤泥浮选效果最好,此时精煤产率为46.28%,精煤灰分为11.76%,可燃体回收率最高为73.99%,煤泥浮选可行。结合选煤厂实际情况分析了煤泥浮选的必要性,预测了增设煤泥浮选的经济效益,说明增设煤泥浮选系统在施工空间和工艺布置方面完全可行,增设煤泥浮选系统可优化选煤工艺,适应市场变化。浮选精煤可与精煤掺配销售,保持精煤水分稳定,减少因水分损失带来的亏吨现象,减少煤泥积压,缓解企业压力,增加销售收入1530.9万元/a。     

A preliminary study on the effectiveness of inquiry-based activities for addressing misconceptions of undergraduate engineering students

This paper presents results from a preliminary study of the effectiveness of using inquiry-based activities to address misconceptions held by undergraduate engineering students in heat transfer and thermodynamics. These targeted misconception areas were identified previously as both important and difficult for students to master by a panel of engineering educators. Five separate inquiry-based activities (two physical experiments and three computer simulations) were developed and tested for their effectiveness at producing conceptual change during a 4-year study. Students’ conceptual change was assessed with concept inventories used in a pre-test–post-test design. The research examined students’ ability to answer conceptual questions both directly coupled with the developed activity and questions that required students to apply the targeted concept in new contexts. These assessments were done both immediately after the activity and 10 weeks later. Students’ performance generally improved in all areas, suggesting that the activities were effective for promoting conceptual change.     

聚酯复合催化剂的应用

使用3种不同的催化剂Sb2O3、SbAc3和自制的复合催化剂合成聚酯树脂，本文对比了3种催化剂对缩聚反应时间和加工过程中粘度损失的影响，提出使用复合催化剂可以显著提高产品的白度，以满足在包装领域的实际应用要求。     

The AFm phase in Portland cement

The AFm phase of Portland cements refers to a family of hydrated calcium aluminates based on the hydrocalumite-like structure of 4CaO·Al₂O₃·13-19 H₂O. However OH⁻ may be replaced by SO₄²⁻ and CO₃²⁻. Except for limited replacement (50 mol%, maximum) of sulfate by hydroxide, these compositions do not form solid solutions and, from the mineralogical standpoint, behave as separate phases. Therefore many hydrated cements will contain mixtures of AFm phases. AFm phases have been made from precursors and experimentally-determined phase relationships are depicted at 25 °C. Solubility data are reported and thermodynamic data are derived. The 25 °C stability of AFm phases is much affected by the nature of the anion: carbonate stabilises AFm and displaces OH and SO₄ at species activities commonly encountered in cement systems. However in the presence of portlandite, and as carbonate displaces sulfate in AFm, the reaction results in changes in the amount of both portlandite and ettringite: specimen calculations are presented to quantify these changes. The scheme of phase balances enables calculation of the mineralogical balances of a hydrated cement paste with greater accuracy than hitherto practicable.     

辽河油田稠油废水生物治理初步研究

针对油田废水中含有大量难降解性物质、可生化性差、水质变化大的特点,本实验设计时充分利用生物处理应用范围广,经济合理的特性,采用了“厌氧-好氧”相结合的工艺对辽河油田废水进行了初步实验研究。实验结果表明,在稳定运行后期,出水COD质量浓度为147—160mg／L,去除率高于60％;石油类质量浓度为1．00～1．16mg／L,去除率高于89％;挥发酚质量浓度为0．023～0．068mg／L,去除率高于80％;氨氮质量浓度为1．00—1．28mg／L,去除率高于75％。     

一种新的钢塑复合管制造技术

介绍了一种新的钢塑复合管连续制造技术,其特点是：在钢带焊接成管时通人惰性气体进行冷却,将焊道温度降低到PVC分解温度以下,从而避免与之粘连的PVC树脂分解。由于采用了冷却的方式,焊接部位与两管结合部位的距离可以缩短,减少了挤出压力,提高了挤出速度;可以缩短芯棒和口模的距离,使二者易于调节同心,挤出的管材的壁厚均匀。由于冷却的惰性气体中不含氧,焊接管不会产生粗糙易脱落的氧化膜,两管复合时不会因此处的薄弱环节而分层。