Highly ordered graphene architectures by duplicating melamine sponges as a three-dimensional deformation-tolerant electrode

In this study, macroscopic graphene-wrapped melamine foams (MF-G) were fabricated by an MF-templated layer-by-layer (LBL) assembly using graphene oxide as building blocks, followed by solution-processed reduction. By concisely duplicating sponge-like, highly ordered three-dimensional architectures from MF, the resulting MF-G with an interconnected graphene-based scaffold and tunable nanostructure was explored as compressible, robust electrodes for efficient energy storage. A thin layer of pseudocapacitive polypyrrole (PPy) was then attached and uniformly coated on MF-G, resulting in a well-defined core–double-shell configuration of the MF-G-PPy ternary composite sponges. The as-assembled devices exhibited enhancement of supercapacitor performance, with a high specific capacitance of 427 F·g^?1 under a compressive strain of 75% and an excellent cycling stability with only 18% degradation after 5,000 charge–discharge cycles. Besides, the MF-G-PPy electrode maintained stable capacitance up to 100 compression–release cycles, with a compressive strain of 75%. These encouraging results thus provide a new route towards the low-cost, easily scalable fabrication of lightweight and deformation-tolerant electrodes.

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层层组装聚马来酸十醇酯多层膜固定相

采用层层组装技术,在色谱硅胶表面交替沉积带相反电荷的聚烯丙基胺盐酸盐（ PAH）和聚乙烯－alt－马来酸十醇酯（ PEMADEC）,制备一种新型聚电解质多层膜（ PAH／PEMADEC）6包覆的硅胶色谱固定相,利用红外光谱和元素分析表征多层膜结构。以6种苯的衍生物和9种苯胺类化合物为分析物,评价PAH／PEMADEC多层膜固定相的色谱性质。结果显示多层膜固定相与分析物间同时存在疏水和亲水相互作用,为制备混合模式固定相提供了一种新途径。     

聚电解质的层层自组装模型及参数探讨

利用静电自组装技术在载波片基底上制备了壳聚糖/磺化木质素多层薄膜,并运用紫外―可见(UV-Vis)光谱等方法对其组装过程进行了表征。结果表明:壳聚糖/磺化木质素层层自组装是一个指数增长过程,其指数增长的数学模型可以描述为:Y=a×en/b+c,其中Y代表膜增长过程的吸光度、频率、质量、厚度等物理性能,n代表层数;a、b和c为常数。由于许多文献报道的自组装例也都可以用此指数增长模型进行描述,为此结合实验和文献数据对影响参数a、b和c的因素进行了探讨。     

聚合电解质在纸浆纤维表面多层沉积的研究

根据层层沉积技术原理,研究了在带负电荷的纸浆纤维表面构筑多层沉积膜过程中Zeta电位的变化和影响纤维吸附聚合电解质的因素。结果表明:依靠阴离子和阳离子之间的静电引力作用,实现了纸浆纤维表面聚合电解质的多层沉积,当聚合电解质吸附量达到一定数值后,纤维表面的电性发生反转。在聚合电解质的多层沉积过程中,纸浆Zeta电位的变化,可以作为沉积过程的监测指标。沉积体系的离子强度和纸浆打浆度是影响聚合电解质吸附量的重要因素。     

Preparation and tribological behavior of Cu-nanoparticle polyelectrolyte multilayers obtained by spin-assisted layer-by-layer assembly

Polyelectrolyte multilayers (PEMs) fabricated by spin-assisted layer-by-layer assembly technique were used as nanoreactors for in-situ synthesis Cu nanoparticles. Chemical reaction within the PEMs was initiated by a reaction cycle in which Cu²⁺ was absorbed into the polymer-coated substrate and then reduced in NaBH₄ solutions. Repeating the above process resulted in an increase in density of the nanoparticles and further growth in the dimension of the particles initially formed. So, different Cu-nanoparticle polyelectrolyte multilayers were formed in the process. The friction and wear properties of Cu-nanoparticle PEMs formed by different reaction cycles were investigated on a microtribometer against a stainless steel ball. The PEMs reinforced with Cu nanoparticles, prepared under the best preparation conditions, possess good tribological behavior, because of the weakened adhesion between the PEMs and the substrate and decreased mobility of the polymeric chains in the presence of excessive Cu nanoparticles generated at larger reaction cycles.     

叠前逐层成像速度建模方法及其应用

叠前深度偏移的效果如何取决于建立的速度-深度模型正确与否。通常以叠后偏移数据的构造解释结果为构造背景，以叠加偏移的均方根速度为初始速度，来制作初始速度-深度模型，然后再经反复迭代，求得最终的速度一深度模型。但是．当构造复杂、速度变化剧烈时．叠偏剖面成像差．不能得到正确的构造．使这种制作速度-深度模型的方法难以得到预期结果。以EAGE/SEG盐丘模型为例．探讨了在从叠加偏移剖面中无法得到正确构造形态和速度的情况下，采用叠前逐层成像速度建模的方法来求取叠前深度偏移速度-深度模型的处理方法．并将其应用于实际地震数据处理，得到了成像效果良好的剖面。     

Cu2SnS3薄膜的制备及性能研究

采用LBL(layer-by-layer)法制备了Cu2SnS3薄膜.即首先采用电化学方法在SnO2衬底上制备SnS薄膜,然后又在其上用化学沉积法制备CuS薄膜,最后进行退火处理得到厚度约为960 nm的Cu2SnS3薄膜.探讨了薄膜的制备机理、生长速度、结构和光学特性.制备的薄膜为多晶(Cu2SnS3)72z(三斜或假单斜晶系)结构,其直接光学带隙约为1.05 eV.     

A Green Method to Fabricate Polyethyleneimine-Alginate Multilayer Coatings Modified Polyurethane Foam for Cu2+ Adsorption from Aqueous Solution

In this study, flexible polyurethane foam (FPUF) was modified with bio-based coatings composed of polyethylenimine (PEI) and alginate (ALG), fabricated by layer-by-layer (LbL) self-assembly. LbL self-assembled coatings modified FPUFs were studied for their potentials for removing Cu²⁺ ions from aqueous solutions by using batch adsorption technique, as a function of assembled bilayers number, pH value, carrier amount and adsorption time. The maximum adsorption capacity of the modified FPUF was shown to be 54 mg/g for Cu²⁺. Results suggested that the LbL self-assembly could potentially be a promising cost-effective technique for fabricating advanced adsorbent materials for removing pollutants from wastewater.     

层层自组装阻燃改性聚酯织物的制备及其性能

为解决阻燃聚酯织物熔滴严重的问题,采用紫外光(UV)辐照接枝共聚技术,通过1-羟基环己基苯甲酮的光引发作用,将阴离子型丙烯酸(AA)接枝到阻燃聚酯织物表面,在此基础上设计了γ-氨丙基三乙氧基硅烷(KH-550)与磺丁基-β-环糊精(SBE-β-CD)抑熔滴体系,在接枝织物表面进行层层自组装制备阻燃抑熔滴聚酯织物,并对改性后织物的形貌、热稳定性和阻燃性能进行表征。结果表明:引发剂质量分数为4%,AA质量分数为12%,紫外光照射时间为10 min时,阻燃聚酯的接枝率较优,为5.08%,但随着接枝率的增加其极限氧指数(LOI值)有所降低;层层自组装改性后的聚酯织物,在组装层数为12时,其极限氧指数可达到28%,成炭明显,垂直燃烧测试无熔滴产生,燃烧性能得到明显改善。     

层层自组装多糖微胶囊的制备及其缓释型纯棉织物修饰应用

为制备生物相容性功能纺织材料,采用层层自组装技术将带有不同电荷的海藻酸钠(Alg)、壳聚糖(Chi)、透明质酸(HA)组装到碳酸钙模板上,利用乙二胺四乙酸(EDTA)去除模板,得到Alg/ Chi/ HA生物多糖微胶囊;利用超景深三维显微镜、扫描电子显微镜、红外光谱、综合热分析仪研究了微胶囊的形貌结构及热稳定性。结果表明:Alg/Chi/HA多糖微胶囊具有很好的中空结构及较强的稳定性;考察了多糖微胶囊吸附释放行为及其随pH值的变化规律,发现Alg/Chi/HA多糖微胶囊具有良好的pH值响应性;进一步将Alg/Chi/HA多糖微胶囊整理至棉纤维上,以制备缓释型功能纺织材料,为功能纺织品开发提供有益的实践经验与技术储备。