《材料概论》第二版已由同济大学出版社正式出版

《材料概论》第一版从2003年问世以来,受到了广大读者的好评,很多高校将该书作为教材使用,连续印刷了多次仍供不应求．考虑到原书中涉及到的一些国家标准现已更新,部分内容已经不能很好地适应时代的需求,而且,材料工业的迅猛发展也带来了一系列的环境问题,保护环境、节约能源和资源已经成为全球的共识,可持续发展已成为人类的共同话题,世界各国都在为这一目标而努力．     

热处理温度对天然闪锌矿光催化活性的影响

研究了热处理温度对天然闪锌矿光催化活性的影响,采用XRD分析不同热处理温度下材料成分和结构的变化,采用罗丹明B染料废水评价材料的光催化活性。结果表明:未经热处理及400℃热处理的成分均为纯硫化锌,而热处理温度为600℃以上的闪锌矿中部分硫化锌转变为氧化锌。未经热处理的闪锌矿具有一定的光催化活性;400℃热处理的闪锌矿表现出更高的光催化活性,经太阳光照射3 h后,其对罗丹明B染料废水的脱色率达到15.32%;热处理温度600℃以上的闪锌矿几乎没有光催化活性。     

碎屑及长江淤沙配制复合砂的试验研究

以长江淤沙和碎屑为原料,根据中砂的要求配制复合砂,并研究了其空隙率、颗粒级配、细度模数等性质。利用一定配比的复合砂成型水泥胶砂并检测了水泥胶砂的流动度、干缩率、强度等性能。试验结果表明,复合砂具有较高的密实度,复合砂配制的水泥胶砂流动性好,早期、中期、后期强度发展都优于由普通中砂配制的水泥胶砂,两者的干缩率相差不大,说明用复合砂代替天然砂来配制胶砂在技术上是可行的。     

保护层厚度对混凝土中钢筋锈蚀的影响

混凝土中的钢筋锈蚀破坏是混凝土结构失效破坏的最主要原因.通过电化学测定,研究了保护层厚度对钢筋锈蚀的影响,研究表明:增大混凝土保护层厚度能有效延缓混凝土中钢筋的锈蚀,延长钢筋开始锈蚀的时间,保护层厚度越大,越能延长钢筋开始锈蚀的时间;进入钢筋开始锈蚀阶段后,保护层比较厚的混凝土中钢筋锈蚀速率增长的较慢;在稳定锈蚀阶段,保护层厚度越大.稳定腐蚀电流密度就越小,保护层厚度和稳定腐蚀电流密度存在一定的函数关系,且数据相关性良好.     

膨胀型复合矿物掺合料对混凝土短期抗冻性能的影响

研究了添加膨胀组分的复合矿物掺舍料混凝土的短期抗冻性能。设计了20个配合比试验来评价混凝土的性能,研究发现,在掺合料取代率为40％时混凝土具有较高的短期抗冻性,对于矿粉-膨胀组分复合型掺合料,膨胀剂占掺合料比例从8％～12％变化时,混凝土短期抗冻性能随膨胀剂掺量的增加而增大。     

外墙外保温体系及其应用技术(一)

外墙外保温技术是节约建筑能耗的一种重要途径。论述了3种外墙外保温体系的优缺点和材料选择以及施工过程中应注意的问题。通过聚苯板与胶粉聚苯颗粒的对比,得出两种保温材料的使用条件。     

含钛矿渣制备及其对水泥性能的影响研究

通过实验室合成不同钛含量的粒化高炉矿渣,研究了矿渣中钛含量对矿渣水泥性能的影响。研究结果表明,在实验室利用工厂现有高炉渣,配加其他成分重新熔化后制备得到的不同TiO2含量的试验用高炉渣,其基本性能与实际冶炼过程产生的高炉渣相近。在含钛矿渣的开发利用中,应尽可能地降低矿渣中TiO2的含量。即作为水泥混合材利用时应控制矿渣中TiO2含量<10%,这样既能达到较高的强度,又能确保含钛矿渣水泥符合现行国家标准。     

混合材对MSWI制CSA水泥性能的影响

以城市垃圾焚烧飞灰（MSWI）为主要原料,在实验室成功烧制了硫铝酸钙（CSA）水泥熟料.研究了单掺或复掺不同种类、不同掺量的混合材后,CSA水泥的力学性能和水化性能.结果表明：石灰石粉（LI）/矿渣粉（SL）在CSA水泥中较为适用,而粉煤灰（FA）/MSWI的活性较差;单掺4种混合材均对CSA水泥早期强度产生不利影响;单掺LI/SL对后期强度发展有益;复掺混合材较单掺效果好,尤其是试样10％LI＋10％SL、10％LI＋10％MSWI和5％LI＋15 ％SL.     

Static and dynamic leaching experiments of heavy metals from fly ash-based geopolymers

The feasibility of high calcium fly ash (CFA)-based geopolymers to fix heavy metals were studied. The CFA-based geopolymers were prepared from CFA, flue gas desulfurization gypsum (FGDG), and water treatment residual (WTR). The static leaching showed that heavy metals concentrations from CFAbased geopolymers were lower than their maximum concentration limits according to the U.S. environmental protection law. And the encapsulated and fixed ratios of heavy metals by the CFA-based geopolymers were 96.02%–99.88%. The dynamic real-time leaching experiment showed that concentration of Pb (II) was less than 1.1 μg / L, Cr (VI) less than 3.25 mg / L, while Hg (II) less than 4.0 μg / L. Additionally, dynamic accumulated leaching concentrations were increased at the beginning of leaching process then kept stable. During the dynamic leaching process, heavy metals migrated and accumulated in an area near to the solid-solution interface. When small part of heavy metals in “the accumulated area” breached through the threshold value of physical encapsulation and chemical fixation they migrated into solution. The dynamic leaching ratios and effective diffusion coefficients of heavy metals from CFA-based geopolymer were very low and the long-term security of heavy metals in CFA-based geopolymer was safe.     

Utilization of thermally treated flue gas desulfurization (FGD) gypsum and class-C Fly Ash (CFA) to prepare CFA-based geopolymer

The feasibility of utilization of flue gas desulfurization (FGD) gypsum and Class-C fly ash (CFA) to prepare CFA-based geopolymer were studied. The results showed that geopolymer made from 90% CFA and 10% FGD gypsum (FGDG) which was thermally treated at 800 ℃ for 1 h obtained the better compressive strength of 37.0 MPa. The micro characteristics and structures of the geopolymer samples of CFA and CFA-FGDG were tested by XRD, FT-IR, and SEM-EDXA after these samples cured at 75 ℃ for 8 h followed by 23 ℃ for 28 d. Both the geopolymer samples of CFA and CFA-FGDG have significant asymmetric stretching of Al-O/Si-O bonds and Si-O-Si / Si-O-Al bending band. In geopolymer sample of CFA-FGDG, a small quantity of lathy products probably being the ettringite wrapped over the spherical fly ash particle, and the concentration of sulfur is much more than that in geopolymer sample of CFA. It is indicated that FGD gypsum may react during alkali-activated and geopolymeric process.