溶胶凝胶法制备磷钨酸掺杂TiO2薄膜及其光催化性能

以钛酸四丁酯为前驱物，采用溶胶凝胶法制备了磷钨酸掺杂的二氧化钛薄膜。通过XRD、FT-TR对该薄膜进行了表征，研究了薄膜在对氯苯酚光降解中的催化活性。结果表明，当磷钨酸与二氧化钛摩尔比为0.01∶1、薄膜烧结温度600℃、对氯苯酚溶液浓度30 mg/L（pH＝5）、光催化8 h的条件下，对氯苯酚的降解率超过90%，且薄膜可以重复使用。磷钨酸对二氧化钛的光催化活性具有明显的促进作用。     

高陡岩质边坡抗震稳定性的三维有限元分析

岩质边坡在地震作用下稳定性的计算一般采用拟静力法和有限单元法,拟静力法因应用简便而得到大量应用,至今广泛应用于边坡的抗震计算。建立了某溢洪道引渠左侧整体边坡三维有限元模型,选用ADINA软件并采用拟静力法对三维模型进行了抗震稳定性计算和分析,结合有限元分析的结果,提出溢洪道引渠左侧整体边坡抗震措施和建议。     

TiO_2膜光催化降解4,4’-二溴联苯的研究

研究了负载于玻璃上的同定化催化剂TiO2膜光催化降解水中4,4'-二溴联苯(4,4'-DBB)的效果,考察了溶液pH值和4,4'-DBB初始浓度等对TiO2膜光催化降解4,4'-DBB的影响,探讨了降解机理.结果表明.TiO2膜光催化降解水中4,4'-DBB的效果良好,紫外光照射8 b,初始浓度为4 mg/L的4,4'-DBB的降解率高达94%,降解速率随着4,4'-DBB初始浓度的增大而下降.在溶液pH=1时,4,4'-DBB的降解效率最高.超声的加入使降解反应的速率加快.经拟合发现4,4'-DBB的降解符合拟一级反应规律,并推导出动力学方程.     

薄膜负载型TiO_2光催化降解乙酸

利用TiCl_4水解法在玻璃表面制备纳米TiO_2光催化膜,考察了TiO_2光催化膜对乙酸光催化降解过程的影响因素.实验结果表明:使用活化温度为460℃、镀膜4次、表面积168 cm~2的TiO_2光催化膜处理500 mL0.667 mmoL/L的乙酸350 min时,乙酸降解率为80.0%,与等量TiO_2粉末相比光催化膜活性显著增加;当乙酸初始浓度c_0小于0.667 mmoL/L时,光催化降解过程可用Langmuir-Hinshelwood动力学方程来描述;TiO_2膜连续使用5次(30 h)时的光催化活性基本不变;用质量分数为5%的HCl溶液浸泡失去活性的光催化膜1 h,TiO_2光催化膜的活性可完全恢复.     

厌氧附着膜膨胀床处理白酒废水启动实验的研究

对用颗粒活性炭作为载体的AAFEB反应器处理白酒废水的启动实验进行了研究。结果表明：在采用恒定进水COD浓度和pH的条件下,通过不断提高温度到35℃,缩短水力停留时间至8 h,维持床层膨胀率在18%～20%,经36 d反应器成功启动,此时反应器有机容积负荷6 kg COD/（m3.d）,COD去除率达到82.9%,容积...     

Representative measurement of two-dimensional reactive phosphate distributions and co-distributed iron(II) and sulfide in seagrass sediment porewaters

The high degree of heterogeneity within sediments can make interpreting one-dimensional measurements difficult. The recent development and use of in situ techniques that measure two-dimensional distributions of porewater solutes have facilitated investigation of the role of spatial heterogeneity in sediment biogeochemistry. A colourimetric diffusive equilibration in thin films method has been developed that allows two-dimensional, high-resolution measurement of reactive phosphate in sediment porewaters. A method detection limit of 0.22 μM, an effective upper limit of ∼1000 μM and relative standard deviations typically below 5% were achieved. This method was evaluated by deployment in seagrass (Zostera capricorni) colonised sediments, as part of combined probes with similar colourimetric methods for sulfide and iron(II). The two-dimensional, high resolution distributions obtained provide a highly representative measurement of the co-distributions of porewater solutes, allowing heterogeneous features and biogeochemical processes to be observed and interpreted. Microniches of high phosphate concentration >100 μM were observed throughout the distributions and were interpreted to be due to localised zones of rapid organic matter mineralisation, possibly using electron acceptors other than iron(III) oxyhydroxides (e.g. aerobic respiration) as often they did not correspond with microniches of higher Fe(II) concentration.     

碳纤维在钢筋混凝土梁抗弯加固设计中的应用

近年来,在钢筋混凝土结构改造加固工程中,碳纤维材料在加固设计中应用发展迅速.通过工程实例,介绍了碳纤维材料加固技术中提高钢筋混凝土梁抗弯承载力的计算方法和施工工艺.     

Wood Modification Effects on Weathering of HDPE-Based Wood Plastic Composites

The effects of weathering on the constituents of wood and polymer matrix behavior in wood plastic composites (WPCs) were investigated. WPCs were produced from pine, extractives-free pine, and pine holocellulose fibers (60%) together with HDPE (40%). These composites were subjected to xenon-arc accelerated and outside weathering for a total of 1200 h and 120 days, respectively. The color and chemical changes that occurred on the surface of the WPCs were analyzed using a set of analytical techniques. For pine and extractive-free pine filled composites, the results showed that the total color change, lightness, and oxidation increased, while the lignin content decreased. In addition, the weight average molecular weight (Mw) and number average molecular weight (Mn) of extracted HDPE decreased with an increase in exposure time of the composites. However, HDPE crystallinity increased with longer exposure time. Lightness of holocellulose-based WPC changed the least while the change in its HDPE crystallinity was not significant compared to the other composite types. Therefore, holocellulose-based WPC may be preferred for applications where color stability is of high priority.     

TiO2膜光催化降解4，4’-二溴联苯的研究

研究了负载于玻璃上的固定化催化剂TiO2膜光催化降解水中4，4’-二溴联苯（4，4’-DBB）的效果，考察了溶液pH值和4，4’-DBB初始浓度等对TiO2膜光催化降解4，4’-DBB的影响，探讨了降解机理。结果表明，TiO2膜光催化降解水中4，4’-DBB的效果良好，紫外光照射8h，初始浓度为4mg／L的4，4’-DBB的降解率高达94％，降解速率随着4，4’-DBB初始浓度的增大而下降。在溶液pH：1时，4，4’-DBB的降解效率最高。超声的加入使降解反应的速率加快。经拟合发现4，4’-DBB的降解符合拟一级反应规律，并推导出动力学方程。     

Role of Hydrophilic and Hydrophobic Interactions in Structure Development of Zein Films

Zein has been studied for its potential as a biobased polymeric material. Due to the fact that films made exclusively from zein are brittle, composites of zein and oleic acid were prepared in our lab and formed into flexible films. Film properties were believed related to their structure. X-ray scattering measurements on zein films suggested the formation of layers along the plane of the film. Oleic acid seemed to play an important role in layer formation. However, X-ray measurements could not yield information on the nature of the interface between oleic acid and zein. Surface plasmon resonance (SPR) was used to further investigate interaction between zein and oleic acid. Dynamic adsorption of zein from alcoholic solutions onto hydrophilic and hydrophobic surfaces generated by self-assembled monolayers of 11-mercaptoundecanoic acid or 1-octanethiol was monitored by SPR. It was observed that zein had a greater affinity for hydrophilic than for hydrophobic surfaces under the prevalent experimental conditions. A mechanism for structure development of zein-oleate films was proposed based on these results and previous X-ray measurements. It is suggested that the structure development involves hydrophilic adsorption of fatty acids onto the zein surface followed by hydrophobic associations leading to a layered film structure organization.