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1.
1. INTRODUCTION Alkali production by ionic membrane is a new technology. Refining used-brine by chelating resin was reported [1~8]. Zhang et al reported the study of using chalating resin D411 to refine used-brine from alkali production by ionic membrane. Restricted by equipment and technology, in cholro-alkali plant the brine alkalinity is very high (pH>11), so conventional method cannot make the concentration of iron ions in used-brine to meet standard. So far there is no report on th…  相似文献   

2.
电催化剂的结构决定其性能.从微观层面研究表面结构与催化性能之间的内在联系和规律是设计和研制高活性、高稳定性、高选择性电催化剂的基础.本文以本研究组关于氢和氧的吸脱附、乙二醇氧化和CO2还原的研究结果为主,综述了电催化剂表面结构和性能调控方面的研究进展.给出面心立方晶体不同晶带上铂单晶电极的循环伏安特征,电催化性能和规律,在此基础上创建的金属纳米晶体表面结构控制和生长的电化学方法,以及对具有开放结构、高催化活性和高稳定性的Pt和Fe纳米晶催化剂的形状和表面结构控制合成.  相似文献   

3.
超疏水多孔阵列碳纳米管薄膜   总被引:11,自引:1,他引:10  
碳纳米管由于具有特异的力学[1] 、光学[2 ] 、电学[3,4 ] 和磁学性质[5] ,使其在锂离子电池[6 ] 和平板展示器[7] 等方面呈现出广泛的应用前景 .Ebbesen等[8] 对无序碳纳米管材料的浸润性进行了详细研究 ,发现其很容易被水润湿 .然而 ,阵列碳纳米管膜的浸润性研究尚未见报道 .固体表面的浸润性主要由表面化学组分和几何结构两方面控制 .通常 ,加大表面粗糙度可以增强其浸润性 [9~ 16 ] .近来 ,超疏水表面 (即与水的接触角大于 1 5 0°的表面 )的研究显示了广泛的应用背景[13~ 16 ] .这种表面通常可由增加表面粗糙度和降低表面能来制备[1…  相似文献   

4.
与二茂铁酰基相连的螺噁嗪的合成、结构及性质   总被引:3,自引:1,他引:2  
在二环已基碳二亚胺(DCC)存在下, 将9′-羟基螺噁嗪与二茂铁甲酸进行酯化缩合, 合成了一种与二茂铁酰基相连的螺噁嗪衍生物2, 用核磁共振氢谱、碳谱、红外光谱、高分辨质谱和X射线单晶衍射对其结构进行了表征. 化合物2在几种有机溶剂中都表现出了良好的光致变色性质; 通过实验证明了在无冰水浴冷却条件下, 用高压汞灯照射时化合物2在二氯甲烷中表现出的特殊变色性是酸致变色的结果; 同时还研究了化合物2在固体PMMA薄膜中的光致变色性质. 在高压汞灯照射下,化合物2在二氯甲烷溶液中显示了良好的荧光性. 循环伏安法测定结果表明化合物2具有良好的氧化还原可逆性.  相似文献   

5.
研究了13种钴(Ⅱ)-氨基酸配合物的可逆氧合性能和催化性能之间的关系,通过配合物活化分子氧(O2)氧化环己烯考察其催化性能.结果表明,13种钴(Ⅱ)-氨基酸配合物均具有不同程度的可逆氧合性能和催化活性.配合物完成一个可逆吸氧周期的用时越短,其可逆氧合性能越好,催化性能越差;相反,吸氧周期长及可逆氧合性能差的配合物其催化性能却更好.另外,在对配合物不同配比的研究中发现,Co(Ⅱ)与氨基酸的摩尔比为1∶3(或1∶2)饱和配位时,可逆吸氧性能较好,但其催化性能较差,环己烯转化率较低;在1∶1型配位不饱和时,吸氧的可逆性较差,但催化性能优良,环己烯的转化率可达82.5%.结合结构分析和理论计算的结果可知,不同钴(Ⅱ)-氨基酸配合物的氧合可逆性和催化性能的差异,主要归因于氨基酸配体的残基与Co(Ⅱ)的结合能力的不同.氨基酸配体的残基与Co(Ⅱ)的结合能力越好,越有利于配合物由高自旋态向低自旋态转化,并与O2可逆结合,不利于烯烃基的取代,配合物表现出较差的催化性能,反之亦然.  相似文献   

6.
不饱和聚酯/玻璃纤维复合材料的研究   总被引:1,自引:0,他引:1  
综述了国内外近年来不饱和聚酯(UPR)/玻璃纤维复合材料的研究与开发的进展,包括不饱和聚酯用量对不饱和聚酯/玻璃纤维复合材料介电性能的影响,光和高能辐射对玻璃纤维/不饱和聚酯树脂复合材料老化性能的影响。重点介绍了不饱和聚酯组成、界面改性、防收缩剂和玻璃纤维分布对玻璃纤维/不饱和聚酯树脂复合材料性能的影响。  相似文献   

7.
The physical and chemical properties of organic semiconductors are closely related to their aggregation structure. Tuning of aggregation structure and electrical property is important for the application in organic electronics. In this study, a facile way to tune the aggregation structure and electrical property of 2.6-diphenyl-anthracene (DPA) is realized by using the octadecyltrichlorosilane (OTS) modification layer with different density which is fabricated by controlling reaction temperature and time. Compared with low density OTS, DPA forms larger grain size, less grain boundaries, and better molecular ordering on high density OTS surface. As a result, the charge transporting mobility of DPA film on high density OTS surface is about two orders of magnitude higher than that on low density OTS surface. The tunable aggregation structure and electrical property of DPA demonstrated here would be meaningful for the application of DPA in organic electronics.  相似文献   

8.
In order to meet the increasing demands on high performance foams with excellent dielectric property by modern industries, a new type of high performance foams based on diallyl bisphenol A modified bismaleimide (BDM/BA) resin is first developed in this paper. The effects of processing parameters such as prepolymerization time and temperature, foaming temperature and time as well as the content of blowing agent on the properties and morphology of resultant foams are intensively investigated from the view of processing–property–morphology relationship. Results show that compared with BDM/BA resin, the optimum condition of prepolymerization is 140°C for 60 min, and that of foaming is 160°C for 35 min. Foams based on BDM/BA resin with 9 wt% AC135 have uniform cell distribution, and greatly improved dielectric property. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

9.
Fluorescent dye (DCM-OH) is covalently bridged to organic–inorganic hybrid material to prevent molecular stacking and to get high fluorescence efficiency and laser property. Novel DCM-OH is synthesized to have hydroxyl functional groups and is bridged to trialkoxysilane as a sol–gel precursor. It participates in sol–gel process to synthesize dye-bridged organic–inorganic hybrid material (dye-bridged hybrimer) and solid-state dye laser sample is ready through polymerization. Fluorescence property of dye-bridged hybrimer is compared with DCM-doped hybrimer that is simple mixture of DCM-OH and hybrimer matrix. The covalently bridged structure of hybrimer with DCM-OH prevented the stacking of fluorescent molecules and enhanced concentration stability. The dye-bridged hybrimer shows much higher fluorescence intensity and low color-shift until it reached high concentration in comparison with DCM-doped system. And the proper lasing property is observed in dye-bridged hybrimer samples.  相似文献   

10.
研究了13种钴(Ⅱ)-氨基酸配合物的可逆氧合性能和催化性能之间的关系, 通过配合物活化分子氧(O2)氧化环己烯考察其催化性能. 结果表明, 13种钴(Ⅱ)-氨基酸配合物均具有不同程度的可逆氧合性能和催化活性. 配合物完成一个可逆吸氧周期的用时越短, 其可逆氧合性能越好, 催化性能越差; 相反, 吸氧周期长及可逆氧合性能差的配合物其催化性能却更好. 另外, 在对配合物不同配比的研究中发现, Co(Ⅱ)与氨基酸的摩尔比为1:3(或1:2)饱和配位时, 可逆吸氧性能较好, 但其催化性能较差, 环己烯转化率较低; 在1:1型配位不饱和时, 吸氧的可逆性较差, 但催化性能优良, 环己烯的转化率可达82.5%. 结合结构分析和理论计算的结果可知, 不同钴(Ⅱ)-氨基酸配合物的氧合可逆性和催化性能的差异, 主要归因于氨基酸配体的残基与Co(Ⅱ)的结合能力的不同. 氨基酸配体的残基与Co(Ⅱ)的结合能力越好, 越有利于配合物由高自旋态向低自旋态转化, 并与O2可逆结合, 不利于烯烃基的取代, 配合物表现出较差的催化性能, 反之亦然.  相似文献   

11.
Conventional polymer membranes suffer from low flux and serious fouling when used for treating emulsified oil/water mixtures. Reported herein is the fabrication of a novel superhydrophilic and underwater superoleophobic poly(acrylic acid)‐grafted PVDF filtration membrane using a salt‐induced phase‐inversion approach. A hierarchical micro/nanoscale structure is constructed on the membrane surface and endows it with a superhydrophilic/underwater superoleophobic property. The membrane separates both surfactant‐free and surfactant‐stabilized oil‐in‐water emulsions under either a small applied pressure (<0.3 bar) or gravity, with high separation efficiency and high flux, which is one to two orders of magnitude higher than those of commercial filtration membranes having a similar permeation property. The membrane exhibits an excellent antifouling property and is easily recycled for long‐term use. The outstanding performance of the membrane and the efficient, energy and cost‐effective preparation process highlight its potential for practical applications.  相似文献   

12.
Soluble polyimide-type alignment layer is widely used in in-plane switching (IPS) liquid crystal display (LCD) because of its excellent reliability owing to high imidisation ratio during long-term driving, high voltage-holding ratio and low ion density. Nevertheless, it exhibits slow direct current (DC) discharging property due to its high resistivity, causing significant DC image-sticking problem. In this study, we doped inorganic salt to control the resistivity of soluble polyimide-type alignment layer and found that this approach reduced DC image sticking greatly without any loss of reliability property in IPS-LCD.  相似文献   

13.
有机硅改性有机合成树脂的研究状况   总被引:1,自引:0,他引:1  
有机硅聚合物具有优异的耐候性、耐玷污性和耐高低温性,高度的疏水性,良好的透气性等被广泛应用.各种有机合成树脂有各自的优点和缺点,它们的缺点正好是有机硅聚合物的优点.将有机硅引入有机合成树脂,利用有机硅优点改进有机合成树脂的不足,使有机硅和有机合成树脂的性能更加完善,这对有机硅和有机合成树脂工业发展具有重大的意义.因此有机硅改性有机树脂是近年来研究的热点.本文简单综述了几种有机硅化学改性有机合成树脂的性能特点、制备方法及研究发展状况.  相似文献   

14.
In order to evaluate the dispersing properties of polycarboxylate-type superplasticizers (PCs) with different molecular weight in cement pastes, PCs with different molecular weight (low, medium, high) were synthesized, and used as superplasticizer for cement suspensions. The effect of molecular weight of PC on the zeta potential, adsorption, fluidity of the corresponding cement suspensions was investigated systematically, and total interparticle potential energy between particles was calculated. The results show that, the higher molecular weight of PC, the larger adsorption amount of PC. PC with medium molecular weight presents a better dispersing property than PC with high molecular weight, while PC with low molecular weight falls in between. The maintaining dispersing ability of PC for cement particles is weakened gradually with the increasing of molecular weight. The changing rule of total interparticle potential energy produced by PC is in accordance with the changing rule of dispersing property of PC in cement pastes. This indicates that the calculated results of total interparticle potential energy further support the explanation of dispersing property difference of PC in theory. This article uses the sum of electrostatic energy and steric hindrance potential as the total interparticle potential energy to evaluate the dispersing property of PC for the first time, which is meaningful for evaluation of dispersing property of polymer dispersant adsorbed on particle surfaces.  相似文献   

15.
林进义  陆丹  黄维 《高分子科学》2016,34(11):1311-1318
Molecular aggregates in conjugated polymer(CP) solution can propagate into mesoscale morphology of the relevant film and further dominate the optoelectronic property. Herein, we probed the aggregation behavior of poly(9,9-dioctylfluorene-2,7-diyl)(PFO) and studied its influence on the photophysical property in 1,2-dichloroethane(DCE) solution, where the contents of β-phase or-aggregates increased with prolonged aging time. Thereinto, high quality β-film was fabricated from DCE solution with critical aggregate time of 6 min. The film exhibited excellent surface morphology and characteristic emission of β-phase. Meanwhile, films prepared from aged DCE solutions exhibited high crystallinity, which was promising to obtain higher photoluminance efficiency and charge transport ability simultaneously. Therefore, it is significant to get deep insight into the aggregation behavior of CP, which is involved not only with the solution-processing technology of plastic device, but also with the optoelectronic property of CP.  相似文献   

16.
本文综合了Formvar膜强度大和火棉胶膜分散性好的优点,制备出了Formvar-火棉胶双层支持膜。Formvar膜在下层增大了膜的强度,火棉胶膜在上层改善了膜的分散性。根据电镜对支持膜的特殊要求,摸索出了制备双层支持膜的原料溶液的浓度范围及浓度配比范围,并且通过红外光谱(IR)证实了双层支持膜结构的存在。通过实际应用,发现双层支持膜具有高分辨率、强电子束照射下膜保持稳定不破损等优点,双层支持膜比以前传统使用的单层支持膜在许多方面都取得了较大的改善,尤其适用于纳米材料的电镜观察,因此,值得进一步推广应用。  相似文献   

17.
La(OH)(3) nanorods were self-stacked on the glass slide substrates using an aqueous suspension obtained from the hydrolysis of LaOCl. The key for producing a high optical quality film of La(OH)(3) lies in the preparation of an aqueous suspension in which La(OH)(3) nanorods are well dispersed. These thin-film coatings of La(OH)(3) nanorods led to a significantly reduced reflective losses in the visible region, exhibiting an attractive and potentially useful single-layer antireflection property. Furthermore, La(OH)(3) nanorod layer provides a sufficiently porous and rough surface required to achieve superhydrophilicity. Thus, when SiO(2) nanoparticles of ca. 20nm in diameter were deposited onto La(OH)(3) layer of high roughness, the resulting La(OH)(3)/SiO(2) film demonstrated an interesting nanoporosity-derived superhydrophilicity and antifogging property with no significant loss of antireflective property.  相似文献   

18.
阵列聚合物纳米柱膜的超疏水性研究   总被引:8,自引:2,他引:6  
浸润性(又称润湿性,Wettability)是固体表面的一个重要特征,它主要由表面化学组成和表面的几何结构两方面控制[1~5].近年来,超疏水性固体表面由于在防雪、防污染、抗氧化以及防止电流等方面都有非常广阔的应用前景,引起了人们的极大关注[6~11].  相似文献   

19.
有应用前景的低感高能炸药研究进展   总被引:2,自引:0,他引:2  
概述了有应用前景的高能低感炸药的研究成果,从改善现有高能炸药晶体品质和合成新的高能低感炸药方面,总结了大幅度降低炸药冲击波感度的研究现状。  相似文献   

20.
含稀土铽(Ⅲ)配合物透明树脂的制备及性能研究   总被引:13,自引:1,他引:12  
含稀土元素的有机高分子 具有稀土离子独特的光、电、磁特性,又具有有机高分子材料优良的性能,是极具潜在应用价值的功能材料,早在1963年,Wolff和Pressley首次研究以高分子为基质的稀土荧光材料,引起了人们的广泛兴趣,80年代以来,高分子链上直接键合稀土配合物的研究也引起了化学家的注意。Okamoto和李文连等在较高稀土浓度下仍可以制成透明柔韧的薄膜。而由于稀土无机物与树脂的相容性差,难以均匀地分散到树脂中,所以获得发光功能高分子体相材料十分困难,本文首次报道将几种稀土铽(Ⅲ)配合物复合于苯乙烯(St)/甲基丙烯酸(HMA)的共聚体系之中,制备了具有发光功能的透明树脂,对其相关性能进行了研究,考察了稀土元素含量、组分配比等因素对聚合物透明性和发光性能的影响,结果表明:高分子网络给稀土配合物提供了稳定的化学环境,有利于展现其优良的发光性能,同时,稀土配合物赋予了光学树脂新的功能性。  相似文献   

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