二氧化锰催化分解室内空气中甲醛的研究

甲醛作为室内空气中的主要污染物,具有来源广泛、释放周期长和致癌等特点。二氧化锰因其较高的低温催化活性和低毒廉价优势,被应用于甲醛的催化分解。本文从二氧化锰负载贵金属、二氧化锰结构调控、二氧化锰与其他非贵金属材料复合三方面,综述了二氧化锰催化分解甲醛的研究进展,探讨分析了负载贵金属、晶型与形貌、层间/隧道内阳离子、表面缺陷、原子掺杂以及与其他材料复合等结构调控策略对二氧化锰催化分解甲醛性能的影响,并总结了贵金属与非贵金属催化分解甲醛机理的区别。最后,分析了现阶段室内甲醛净化面临的问题和挑战,展望了二氧化锰催化分解甲醛的主要研究方向和发展趋势。     

ADS纯化器中活性炭动态吸附的实验研究

ADS不纯氦气回收净化系统中采用椰壳活性炭来吸附氦气中的杂质,不纯氦气中的杂质主要包括氮气、氧气、水、CxHy和少量的氩气、氢气、油蒸汽等。通过实验研究了氮气、氧气、氩气和氢气四组分气体在椰壳活性炭中的动态吸附特性,比较了动态吸附过程中各组分之间的相互影响,通过LRC负载关联式模型对各组分动态吸附量进行了拟合,给出了氦气净化过程中椰壳活性炭用量的计算方法。     

Surface Plasmon Resonance Microscopy: From Single-Molecule Sensing to Single-Cell Imaging

Surface plasmon resonance microscopy (SPRM) is a versatile platform for chemical and biological sensing and imaging. Great progress in exploring its applications, ranging from single-molecule sensing to single-cell imaging, has been made. In this Minireview, we introduce the principles and instrumentation of SPRM. We also summarize the broad and exciting applications of SPRM to the analysis of single entities. Finally, we discuss the challenges and limitations associated with SPRM and potential solutions.     

薄层色谱法同时测定邻苯二酚、间苯二酚和对苯二酚异构体

研究了在自制硅胶薄板上邻苯二酚,间苯二酚异构体的薄层色谱特性。展开剂为本：乙醚：冰醋酸＝７：２：１（Ｖ／Ｖ／Ｖ）,Ｒｆ值分别为０．５９,０．５３,０．４８。检测限分别为１．０７×１０＾－４,１．６４×１０＾－４,１．９０×１０＾４ｍｏｌ／Ｌ。其他常见酚不干扰测定。可应用于实际样品的测定,回收率为９６％－１０４％。     

1-烷基-4-氨基-1,2,4-三唑类含能离子液体的溶解性能

基于NO3-、ClO4-、N(CN)2-、[2,4,5-TNI]^-和[3,5-DNTZ]^-阴离子,以及1-烷基-4-氨基-1,2,4-三唑阳离子合成了系列环境友好型含能离子液体,通过¹H NMR对其进行了结构表征;采用ab initio结合MP2/6-311G++(2d,p)方法计算了1-烷基-4-氨基-1,2,4-三唑类含能离子液体和溶剂之间的分子间作用能以及含能离子液体的偶极距;系统研究了分子结构、极性以及分子间作用能对该系列含能离子液体的溶解性能的影响。 结果表明:当阳离子不同时,[BATZ]NO₃与水的ΔE绝对值最大为40.7 kJ/mol,当阴离子不同时,[BATZ][3,5-DNTZ]与水的ΔE绝对值最大为45.1 kJ/mol;上述含能离子液体的极性大小顺序为[BATZ][3,5-DNTZ]>[BATZ][2,4,5-TNI]>[BATZ]N(CN)₂>[BATZ]ClO₄>[RATZ]NO₃;最后,1-烷基-4-氨基-1,2,4-三唑类含能离子液体的溶解度随着溶剂介电常数ε的减小、取代烷基链长的增加、阴离子体积的增大以及分子间作用能的减小而降低,即含能离子液体在溶剂中的溶解度大小顺序为[BATZ][3,5-DNTZ]>[BATZ][2,4,5-TNI]>[BATZ]NO₃>[BATZ]ClO₄>[BATZ]N(CN)₂>[PATZ]NO₃>[HATZ]NO₃>[DATZ]NO₃,其中,[BATZ][2,4,5-TNI]在水中溶解度最大为10.0327 g/10 g。     

燃气驱动热声发动机中加热器的设计与实验验证

加热器在热声发动机的能量传递和转化过程中起着重要作用,是热声发动机的核心部件之一。目前热声发动机大多采用电能驱动,采用燃气直接燃烧驱动将对热声发动机的实用化具有积极促进意义。根据热声发动机的工作特点,以时均流对流换热公式为依据,设计了一种新型燃气燃烧驱动加热器,并应用于现有的混合型热声发动机实验台上,取得了较好的实验结果。     

高温富Si环境中C/C复合纤维异化机理研究

随着直拉法热场尺寸的不断增大,单晶硅生产过程中已经大批量采用C/C复合埚帮替代石墨埚帮.但是,由于埚帮处在高温富Si环境中,经过一定时间后碳纤维出现异化现象,致使埚帮失效,高频次的更换增加了企业的生产成本.研究中利用XRD对碳纤维埚帮异化不同阶段物相进行分析,通过SEM对异化后的埚帮形貌进行观察,发现处在高温富Si氛围中的碳纤维变成了碳化硅.通过对单晶硅炉内流场和温度场分析,揭示了碳化硅的形成过程和机理.结合碳纤维硅化过程和反应机理分析了埚帮异化的主要原因,为后续高寿命埚帮设计和延长其使用寿命提供增强策略.     

Preparation and characterization of biosurfactant based on hydrophobically modified alginate

Hydrophobic modified alginate (HM-alginate) was synthesized using a low-energy, environment-friendly process in aqueous solution, with sodium alginate and dodecyl glycidyl ether as starting materials. The HM-alginate was characterized using ¹H NMR, and the reaction efficiency was about 40%. The HM-alginate aggregated in solution; the critical micelle concentration (CMC) was determined using surface tension and dynamic light scattering methods. We observed reasonable agreement between the CMC values obtained by the different techniques, and the CMC was 4.0 × 10^?4 g/mL. The zeta-potential of the HM-alginate in aqueous solution was about ?82 mV, which is higher than ?51 mV of the sodium alginate. Rheology measurements showed that the HM-alginate solution exhibits a Newtonian behavior at all shear rates, whereas the apparent viscosity is very low. The solubility of the liposoluble substance Sudan IV increased significantly with HM-alginate concentration. This result is promising for potential applications of HM-alginate as an ecology-safe material to encapsulate lipophilic substances.     

Sequence Effects in Conjugated Donor–Acceptor Trimers and Polymers

To investigate the sequence effect on donor–acceptor conjugated oligomers and polymers, the trimeric isomers PBP and BPP , comprising dialkoxy phenylene vinylene ( P ), benzothiadiazole vinylene ( B ), and alkyl endgroups with terminal olefins, are synthesized. Sequence effects are evident in the optical/electrochemical properties and thermal properties. Absorption maxima for PBP and BPP differ by 41 nm and the electrochemical band gaps by 0.1 V. The molar emission intensity is five times greater in PBP than BPP . Both trimers are crystalline and the melting points differ by 17 °C. The PBP and BPP trimers are used as macromonomers in an acyclic diene metathesis polymerization to give PolyPBP and PolyBPP . The optical and electrochemical properties are similar to those of their trimer precursors—sequence effects are still evident. These results suggest that sequence is a tunable variable for electronic materials and that the polymerization of oligomeric sequences is a useful approach to introducing sequence into polymers.