Water-assisted formation of novel molecularly imprinted polymer membranes with ordered porous structure

A functional polymer, poly(styrene-stat-acrylonitrile-stat-vinyl-2,4-diamino-1,3,5-triazine) (modified SAN, mSAN) with 13.6% triazine units, was synthesized. Using mSANs as the functional polymers and poly(styrene-stat-acrylonitriles) (SANs) as the matrix polymers, the molecularly imprinted polymer (MIP) membranes with (S)-5-benzylhydantoin (S-BZH) as template and the Blank membranes without S-BZH were prepared via the water-assisted method. Scanning electron microscopy (SEM) measurement revealed an ordered porous structure on the surface and a sponge-like porous structure in the cross-section of the MIP membranes. Further, the permeation experiments of the template S-BZH and its analogues in methanol solution were carried out with MIP as well as Blank membranes; the results provided evidence for imprint effect of the ordered porous membranes.     

不同老化气氛对催化裂化捕钒剂性能的影响

通过改变老化处理气氛,研究其对催化裂化捕钒剂性能的影响。在水蒸汽和氮气气氛下,含有捕钒组分的催化剂与不含捕钒组分的催化剂催化活性接近,捕钒组分的捕钒效果不显著。在水蒸汽和空气气氛下,随着空气体积分数由0增加到50%,不含捕钒组分的催化剂微反活性由58%升高到69%,重油转化率由68. 82%升高到74. 02%;含有捕钒组分的催化剂微反活性由60%升高到73%,重油转化率由70. 04%升高到77. 10%,焦炭和干气选择性也优于不含捕钒组分样品,体现了捕钒组分的捕钒效果。通过控制老化气氛中SO2质量分数为0或0. 16%,考察SO2对捕钒组分的影响,结果表明,SO2对此捕钒组分的性能影响较小。     

先进适用性测井新技术在中原油田的应用

本文论述了先进适用性测井技术评价方法的地质优势,介绍了中原油田储层的地质特征,展示了测井新技术地质应用效果：准确对裂缝性储层参数进行定量解释,对碳酸盐岩储层进行有效性评价,对地层构造沉积相进行分析,有效地划分水淹程度,直观地识别孔隙中流体性质,有效地识别油干层界限。     

对物理化学考研中van der Waals方程及其应用考点的分析

对物理化学考研中van der Waals方程及其应用的考点进行深入分析,使考物理化学科目的考生能很好的理解和掌握此考点。     

聚苯胺/环氧复合阴极电泳涂料防腐蚀性能的研究

运用插层聚合的方法制备了蒙脱土／聚苯胺复合材料，并进行了表征。将该复合材料通过共混的方式加入聚酰胺／环氧阴极电泳（CED）涂料中配制成聚苯胺／环氧复合阴极电泳涂料，并利用电化学阻抗谱方法对各电泳涂层的防腐性能进行了分析。研究发现：在3．5％NaCl溶液中浸泡10d后，腐蚀介质不能到达涂层／基底金属界面，金属表面没有发生腐蚀反应。随着聚苯胺含量的增加，复合电泳涂膜的阻抗值增加，具有较好的防腐性能。当聚苯胺含量相同时，与掺杂态聚苯胺复合电泳涂膜相比，本征态聚苯胺复合电泳涂膜具有很高的阻抗值，表现出更好的防腐性能。     

A Study on the Friction and Wear Behavior of PTFE Filled with Acid Treated Nano‐Attapulgite

Summary: A solid lubricant composite material was prepared by compression molding PTFE and acid treated nano‐attapulgite. The friction and wear tests were performed on a block‐on‐ring wear tester. Scanning electron microscopy (SEM), energy‐dispersive X‐ray spectrometer (EDS) and DSC were utilized to investigate material microstructures and examine modes of failure. Experimental results showed that there was no significant change in coefficient of friction, but the wear rate of the PTFE composite was orders of magnitude less than that of pure PTFE. Acid treated nano‐attapulgite was superior to untreated nano‐attapulgite in enhancing the wear resistance of PTFE. Moreover, the wear resistance of the composite increased monotonically with increasing treated attapulgite concentration. Investigation of transfer film and analysis of debris for PTFE and its composite showed that acid treated nano‐attapulgite filled to PTFE could facilitate formation of transfer film on the steel ring surface and inhibit breakage of PTFE molecular chain. The PTFE composite with higher heat absorption capacity exhibited improved wear resistance. Furthermore, the steel ring counterface abrasion was not found.

Effect of load on the wear rate of PTFE and its composites.     

Enhanced Hydrolysis of Cellulose to Reducing Sugars on Kaolinte Clay Activated by Mineral Acid

Catalysis Letters - Kaolinite, a natural, layered phyllosilicate, has been used as the solid catalyst for the hydrolysis of cellulose in our previous work. In the present study, kaolinite was...     

高温固相法合成无水磷酸镁实验研究

磷酸镁是重要的精细磷酸盐产品,广泛应用于食品及医药工业。国内外对磷酸镁生产方法的研究一般以结晶磷酸镁为主,而对无水磷酸镁生产方法的研究相对较少。以磷酸和碳酸镁为原料,对高温固相法一步合成无水磷酸镁盐进行了试验研究。结果表明:在控制氧化镁与五氧化二磷物质的量比为3.0、反应温度为1 100~1 250℃、反应时间为30~45 min条件下,得到的磷酸镁产品质量可达到美国食用化学品法典(FCC,2000)食品磷酸镁指标的要求。     

One cationic dinuclear silver(I) complex of dppatc formed in situ by replacing ethylenediamine units of dppeda through aminothiocarbamide

Reaction of silver nitrate with N,N,N′,N′-tetra(diphenylphosphanylmethyl)ethylenediamine (dppeda) in the presence of aminothiocarbamide in CH₂Cl₂/MeOH afforded an unexpected and low-yield binuclear complex [Ag₂(dppatc)₂](NO₃)₂·2MeOH (dppatc = N,N-bis(diphenylphosphanylmethyl)aminothiocarbamide) (1). An X-ray analysis revealed that the [Ag₂(dppatc)₂]²⁺ dication of 1 contains a centrosymmetric double half-open cage structure in which two Ag centers are bridged by a pair of the heteroscopionate dppatc ligands via four Ag-μ-S and four AgP bonds. The in situ-formed dppatc ligand in 1 could be readily generated by one-pot and high-yield reaction of diphenylphosphine with formaldehyde and aminothiocarbamide. Further reaction of AgNO₃ with dppatc could produce 1 in a relatively high yield. The results provided an efficient route to the synthesis of dppatc and also an interesting insight into its coordination chemistry.     

异丁烯-对甲基苯乙烯无规共聚物的合成与表征

以二枯基氯/四氯化钛/2,6 -二叔丁基吡啶为引发体系,在-80℃条件下采用正离子聚合法合成了异丁烯-对甲基苯乙烯无规共聚物(IB -co -p - MeSt),研究了不同单体投料比(摩尔比)下聚合反应的特征,并通过示差折光指数仪/多角激光光散射仪/紫外检测器、核磁共振氢谱、差示扫描量热法和热重分析对无规共聚物进行了表...