邻仲丁基4,6-二硝基苯酚(DNBP)对苯乙烯热聚合阻聚行为研究

用折光指数法考察了90~120℃下邻仲丁基4,6-二硝基苯酚(DNBP)对苯乙烯热聚合的阻聚效果,并从温度和质量浓度(0.02%~1%)两个方面进行研究。实验结果表明,随着温度的升高,阻聚效果逐渐变弱;随着阻聚剂浓度的增加,阻聚效果逐渐变强;温度对于阻聚过程的影响要强于浓度对其的影响;温度为120℃,DNBP浓度超过0.1%时,可以产生表面意义上的诱导期。     

纳米TiO_2改性苯丙乳液内墙涂料的研究

采用物理掺和法,在苯丙乳液中加入锐钛型纳米TiO2,制成内墙涂料,进行抑菌试验和甲醛降解实验研究,分析了纳米TiO2的光催化原理和抗菌机理。结果表明,随着TiO2含量增加,甲醛降解能力和抗菌性能增强,当TiO2含量为4%时效果最好。     

氮掺杂纳米TiO_2改性涂料及其抗菌性能

将自制的氮掺杂锐钛矿型纳米二氧化钛光催化剂作为功能性组分,加入耐光催化氧化的硅丙乳胶涂料中,制备出一种新型光催化功能性建筑涂料,实现了可见光光催化效应。使用紫外-可见光吸收光谱研究该功能性涂料对紫外线的吸收能力;采用菌落计数法研究该涂料在可见光照射下对金黄色葡萄球菌的杀灭性能。同时分析了纳米粉体种类、引入量及方式对涂料紫外线的吸收性能和抗菌性能的影响。     

2,6-二乙酰基吡啶合成方法的改进

优化了2，6—二乙酰基吡啶的合成工艺。以2，6—吡啶二羧酸为原料，经过醇化及克莱森酯缩合反应，合成了2，6—二乙酰基吡啶，2，6—吡啶二羧酸二乙醇和2，6—二乙酰基吡啶的分离收率分别为94．1％和88．9％，2，6—二乙酰基毗啶的质量分数大于99％。     

从假性紫罗兰酮合成β-紫罗兰酮中主要副产物(I)的分离鉴定

假性紫罗兰酮在浓硫酸及 - 2 0°C低温条件下反应 ,主要生成 β-紫罗兰酮 ,少量的 α-及 γ-紫罗兰酮 ,同时生成副产物 ( I)及 ( II)。用 IR、1H NMR及 MS光谱分析方法 ,对副产物 ( I)进行了结构鉴定 ,结构为 3,4,4a,5 ,8,8a-六氢 - 2 ,5 ,5 ,8a-四甲基 - 2 H - 1 -苯并吡喃     

B_2O_3和CaF_2对C_3S-C_(2.75)B_(1.25)A_3-C_2S-C_3A水泥熟料矿物体系力学性能影响

研究了B2O3和CaF2对C3S-C2.75B1.25A3S珚-C2S-C3A熟料矿物体系的组成、结构与力学性能的影响。研究结果表明:在该熟料体系中C3S,C2.75B1.25A3S珔,C2S和C3A的适宜含量分别为50%,10%,25%和15%,B2O3和CaF2的适宜掺量为2%和1.5%。在最佳组成和制备工艺条件下,合成的阿利特-硫铝酸钡钙水泥的1d,3d和28d抗压强度分别达到18MPa,48MPa和95MPa以上,展现了良好的早期力学性能。同时,掺加CaF2能有效降低熟料中游离氧化钙的含量,促进阿利特在低温条件下形成。利用SEM-EDS,XRD等测试手段对熟料的组成、结构及性能进行了分析。     

SBR反应器中反硝化条件下去除苯酚工艺

基于异养反硝化原理,在序批式间歇反应器(SBR)中对反硝化同时降解苯酚的菌种进行了149 d的驯化,驯化通过逐步提高进水中苯酚和NO3--N的浓度进行.驯化结束后,进水苯酚质量浓度达到360 mg/L,葡萄糖质量浓度达到100 mg/L,NO3--N质量浓度达到240 mg/L,水力停留时间6 h,苯酚和NO3--N去除率均大于98%.反应器运行结果表明:进水苯酚质量浓度低于720 mg/L时,SBR反应器运行稳定;高浓度NO2--N(＞60 mg/L)可以严重影响微生物对苯酚以及NO3--N的去除能力,同时反应器中20.5%～23.5%的COD可被用于微生物的细胞合成.     

Isobutane/2-butene alkylation on MCM-22 catalyst. Influence of zeolite structure and acidity on activity and selectivity

The catalytic behavior of the novel MCM-22 zeolite for the continuous alkylation of isobutane with 2-butene has been investigated at a temperature of 50°C, 2.5 MPa total pressure, and a variety of olefin space velocities. At high olefin conversions the MCM-22 zeolite showed a very high initial cracking activity attributable to strong Brønsted acid sites, as well as to the existence of strong diffusional restrictions of the TMP's (formed inside the zeolite) to exit through the channels. At short times on stream (TOS), TMP's account for ca. 40% of the C₈ fraction. The olefin conversion and the cracking activity rapidly decline with TOS, while the alkylate product became richer in dimethylhexenes, indicating a predominance of 2-butene dimerization and a loss of hydrogen transfer activity as the catalyst aged. Moreover, MCM-22 gives less TMP's than large-pore zeolites (USY, beta, mordenite), but more than the mediumpore ZSM-5 at similar 2-butene conversion. The latter catalyst was much more selective for olefin dimerization than for isobutane alkylation, presumably because formation of the bulkier TMP's was strongly impeded in its smaller pores.     

Mg(OH)2及其与红磷复配阻燃聚丙烯复合材料的性能研究

研究了Mg(OH)2和Mg(OH)2/红磷复配体系阻燃聚丙烯材料的性能,选用热塑性弹性体POE对阻燃聚丙烯复合材料进行了增韧改性,结果表明:Mg(OH)2与红磷复配可以减少Mg(OH)2用量,降低对材料力学性能的损耗;POE较好地改善了材料的冲击性能,其添加量为15份时,材料的冲击强度可由8.14kJ/m2增大至12.83kJ/m2。最后利用锥形量热仪验证了Mg(OH)2/红磷复配体系的协同阻燃效应。     

Syntheses of TiO2 photocatalysts by the molten salts method: Application to the photocatalytic degradation of Prosulfuron

Titania photocatalysts were synthesised by the molten salts method by reaction of a titanium precursor with three different alkali metal nitrates (LiNO₃, NaNO₃, KNO₃). The titania powders obtained have been characterised using TEM, XRD, BET and UV-Vis absorption spectroscopy. Their photoactivities were evaluated by degrading a commercial sulfonylurea herbicide, Prosulfuron^®. It has been found that the rate constants increased in the following order: Li2 prepared in KNO₃, with a rate constant 1.4 times smaller than that of P25. The effect of calcination was also studied, especially for the sample prepared in NaNO₃ (TiO₂[Na]). An improvement in photocatalytic activity was observed when TiO₂[Na] was calcined in the region of 700–800 °C. Even though the photocatalytic activities obtained did not exceed or even equal to that of Degussa P25, nevertheless, this study constitutes the first attempt to synthesise titania photocatalysts by the molten salts method.