Facile fabrication of hollow polyaniline spheres and its application in supercapacitor

Polyaniline (PANI) is a promising electroactive material for pseudocapacitor due to the existence of the electronic conjugation structure. Here we demonstrate a novel approach to prepare hollow polyaniline nanospheres. In this process, uniform poly (methyl methacrylate- butyl methacrylate - methacrylic acid) (PMMA-PBMA-PMAA) latex microspheres as self-sacrificial templates were rapidly prepared through an emulsion polymerization method. Then the hollow PANI (H-PANI) nanospheres were obtained directly through an in-situ chemical oxidative polymerization of aniline in the presence of PMMA-PBMA-PMAA microspheres, which can be explained by the “dissolution” of templates and phase separation between the constituent polymers. The structure and morphology of the nanophase materials have been characterized by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) spectra. The specific capacitance of H-PANI is 485.5 F g^?1 at 1 A g^?1 and there is 69% performance attenuation after 500 cycles, which show a promising electrochemical performance.     

Ferromagnetic coupling of Fe3+-VO-Fe3+polarons in Fe-doped ZnO

Room temperature ferromagnetic Fe-doped ZnO with hexagonal wurtzite structure was synthesized by a hydrothermal method under 4 T high pulsed magnetic field. Detailed studies were carried out to survey the effect of magnetic field on morphological, structural and magnetic properties of samples. The results showed that the concentration of oxygen vacancies (VOs) and amount of Fe³⁺ doping in ZnO were improved due to the high magnetic field processing. It proposed that the inherent exchange interaction is mediated by magnetic ions (Fe³⁺) through VOs assist to produce bound magnetic polorans (BMPs), which is responsible for RTFM in Fe-doped ZnO matrix.     

等温冷却时间对Ti-V-Mo复合微合金钢组织转变及硬度的影响

通过OM、SEM、TEM和维氏硬度计等手段研究了不同等温冷却时间对Ti-V-Mo复合微合金钢组织转变、析出行为及硬度的影响,探讨了影响硬度变化的因素。结果表明,Ti-V-Mo复合微合金钢奥氏体化后在630 ℃等温冷却0~3 h,随着等温时间的延长,基体中的铁素体比例不断增加而马氏体和贝氏体比例逐渐降低,硬度呈现先升高再趋于平稳,再升高至其最大值,最后略有下降。60~1200 s时,硬度出现平台是因为纳米级(Ti, V, Mo)C粒子的沉淀强化效果能够弥补相变导致基体软化造成的硬度损失;3600 s时,硬度达到最大值为457 HV,此时纳米级(Ti, V, Mo)C粒子产生的沉淀强化效果最佳。     

22种不同来源信阳毛尖茶的分类比较

为了探究采制时节、产地、等级等因素对信阳毛尖茶品质成分的影响,本文采用高效液相色谱等方法对22个不同来源的信阳毛尖茶中儿茶素、黄酮类、酚酸类、嘌呤碱等品质成分进行测定。主成分分析、聚类分析和偏最小乘法-判别分析显示采制时节是影响信阳毛尖品质成分的主要因素,不同来源信阳毛尖基本可按照采制时节分为明前、雨前和春尾。单因素方差分析显示不同采制时节信阳毛尖茶在8种儿茶素、5种黄酮类、2种嘌呤碱以及没食子酸、游离氨基酸等品质成分上存在极显著差异(P<0.01):明前茶中的游离氨基酸总量和(+)-儿茶素(C)含量最高、而(+)-没食子儿茶素(GC)、(-)-表没食子儿茶素(EGC)、(-)-表儿茶素没食子酸酯(ECG)、(-)-表没食子儿茶素没食子酸酯(EGCG)、没食子酸、芦丁、杨梅素、槲皮素、可可碱含量最低,与雨前茶和春尾茶存在显著(P<0.05)或极显著差异(P<0.01)。不同产地和等级之间C、ECG、(-)-表没食子儿茶素(EGC)等儿茶素;芦丁、花旗松素、杨梅素等黄酮类;以及可可碱、茶碱等嘌呤碱含量存在显著(P<0.05)或极显著差异(P<0.01)。相对而言,四望山毛尖茶中非酯型儿茶素含量较高,而黄酮总量较低;芽头中游离氨基酸和C含量最高,而EGC和杨梅素含量最低,这对信阳毛尖采制时节的识别有一定影响。本文首次基于茶叶中品质成分对不同来源的信阳毛尖进行了分类比较,为明前茶的识别提供了科学依据。     

Alginate-based delivery systems for food bioactive ingredients: An overview of recent advances and future trends

Due to its advantagessuch as ionic crosslinking, pH responsiveness, excellent biocompatibility, biodegradability and low price, alginate has become one of the most important natural polysaccharides extensively used in constructing desired delivery systems for food bioactive ingredients. In this review, the fundamental knowledge of alginate as a building block for construction of nutraceutical delivery systems is introduced. Then, various types of alginate-based nutraceutical delivery systems are classified and summarized. Furthermore, the future trends of alginate-based delivery systems are highlighted. Currently, alginate-based delivery systems include hydrogel, emulsion, emulsion-filled alginate hydrogel, nanoparticle, microparticle, core–shell particle, liposome, edible film, and aerogel. Although alginate has been widely used in the fabrication of food bioactive ingredient delivery systems, further efforts and improvements are still needed. For this purpose, the future perspectives of alginate-based delivery systems are discussed. The feasible research trends of alginate-based delivery systems include the development of novel large-scale commercial preparation technology, multifunctional delivery system based on alginate, alginate oligosaccharide-based delivery system and alginate-based oleogel. Overall, the objective of this review is to provide useful guidance for rational design and application of alginate-based nutraceutical delivery systems in the future.     

移印油墨简介

传统印刷是转移油墨的技术，油墨的地位不言而喻。油墨首先要能和承印材料匹配，也就是印上去不能掉，否则功能再强大的油墨也没有用。其次要适应整个印刷过程，就是印刷适性要好。     

Enhanced optical transmittance and energy-storage performance in NaNbO3-modified Bi0.5Na0.5TiO3 ceramics

Dielectric ceramics with both excellent energy storage and optical transmittance have attracted much attention in recent years. However, the transparent Pb-free energy-storage ceramics were rare reported. In this work, we prepared transparent relaxor ferroelectric ceramics (1 − x)Bi_0.5Na_0.5TiO₃–xNaNbO₃ (BNT–xNN) by conventional solid-state reaction method. We find the NN-doping can enhance the polarization and breakdown strength of BNT by suppressing the grain growth and restrained the reduction of Ti⁴⁺ to Ti³⁺. As a result, a high recoverable energy-storage density of 5.14 J/cm³ and its energy efficiency of 79.65% are achieved in BNT–0.5NN ceramic at 286 kV/cm. Furthermore, NN-doping can promote the densification to improve the optical transmittance of BNT, rising from ∼26% (x = 0.2) to ∼32% (x = 0.5) in the visible light region. These characteristics demonstrate the potential application of BNT–xNN as transparent energy-storage dielectric ceramics.     

城市综合体用电服务探索

对城市综合体概念进行了介绍,并就如何对其提供科学高效的电力运行维护和优质的电力供应保障进行了探索和研究。     

四川省再生铜物质流分析

铜是人类最早发现的古老金属之一,也是我国重要的战略金属矿产。在我国有色金属资源储量严重不足的情况下,再生铜极大程度上缓解了我国铜资源的严重不足,拓宽了铜的来源渠道。本文通过对四川省九家再生铜企业的现场调研,获取了铜产业的流量、流向、再生产情况,并对铜流量、流向、再生产情况进行了分析,同时对金属铜的再生利用社会经济价值和再生利用生态环境价值进行影响评价。结果表明,再生铜比冶炼铜平均节约18.16%的能源,废铜的回收、再利用,无论从节能降耗、缩短生产流程周期,还是从环境保护、改善人类生态环境等各方面都可以产生可观的经济价值和生态价值。基于此,本文绘制了四川省重点金属铜企业年处理量级再生铜产量桑基图,并从生态、经济和政策等方面提出建议。