Spent Grain from Malt Whisky: Assessment of the Phenolic Compounds

In order to extract antioxidant phenolic compounds from spent grain (SG) two extraction methods were studied: the ultrasound-assisted method (US) and the Ultra-Turrax method (high stirring rate) (UT). Liquid to solid ratios, solvent concentration, time, and temperature/stirring rate were optimized. Spent grain extracts were analyzed for their total phenol content (TPC) (0.62 to 1.76 mg GAE/g SG DW for Ultra-Turrax pretreatment, and 0.57 to 2.11 mg GAE/g SG DW for ultrasound-assisted pretreatment), total flavonoid content (TFC) (0.6 to 1.67 mg QE/g SG DW for UT, and 0.5 to 1.63 mg QE/g SG DW for US), and antioxidant activity was measured using 2,2-diphenyl-2-picrylhydrazyl (DPPH) free radical (25.88% to 79.58% for UT, and 27.49% to 78.30% for UT). TPC was greater at a high stirring rate and high exposure time up to a certain extent for the Ultra-Turrax method, and at a high temperature for the ultrasound-assisted method. P-coumaric acid (20.4 ± 1.72 mg/100 SG DW for UT, and 14.0 ± 1.14 mg/100 SG DW for US) accounted for the majority of the phenolic found compounds, followed by rosmarinic (6.5 ± 0.96 mg/100 SG DW for UT, and 4.0 ± 0.76 mg/100 SG DW for US), chlorogenic (5.4 ± 1.1 mg/100 SG DW for UT, and non-detectable for US), and vanillic acids (3.1 ± 0.8 mg/100 SG DW for UT, and 10.0 ± 1.03 mg/100 SG DW for US) were found in lower quantities. Protocatechuic (0.7 ± 0.05 mg/100 SG DW for UT, and non-detectable for US), 4-hydroxy benzoic (1.1 ± 0.06 mg/100 SG DW for UT, and non-detectable for US), and caffeic acids (0.7 ± 0.03 mg/100 SG DW for UT, and non-detectable for US) were present in very small amounts. Ultrasound-assisted and Ultra-Turrax pretreatments were demonstrated to be efficient methods to recover these value-added compounds.     

Preparation and characterization of microcapsules loaded with polyphenols-enriched Uncaria tomentosa extract using spray-dryer technique

Journal of Thermal Analysis and Calorimetry - This work prepared and characterized microcapsule of Uncaria tomentosa (UT) in order to standardize a spray-dryer Uncaria tomentosa extract. The UT...     

High accuracy ultrasonic monitoring of electrochemical processes

Ultrasonic testing (UT) can be used for non-intrusive corrosion monitoring. In this paper, we firstly show that UT is not only capable of monitoring wall-thickness losses, but can also be exploited for tracking electrodeposition processes. All ultrasonic measurements reported are in agreement with analytical predictions and optical surface profile measurements. Since UT is highly sensitive to the coupling conditions and the relative acoustic properties of substrates and deposited materials, it can become an effective tool for studying the interface phenomena in which dissolution and deposition compete. Examples of these include passivation layer formation and scale deposition which are corrosion-inhibiting electrochemical processes.     

生物医用高分子微球研究进展

综述了生物医用高分子微球载体的制备方法、表面功能化途径以及生物活性物质的固定化方法,并对高分子微球在生物医学领域的应用作了简要介绍。     

A new type of functional polymer: Preparation and crosslinking of poly(allenyl glycidyl ether)

The radical polymerization behavior of alkoxyallene containing the epoxy group, allenyl glycidyl ether ( I ), was investigated to obtain the more reactive polymer. The desired polymer was successfully synthesized only by the copolymerization of I with acrylonitrile (AN) at 80°C in DMF, although the homopolymer of I was converted to the crosslinked polymer during its purification. The same number of epoxy and two kinds of methylene groups were simultaneously introduced onto the polymer through propagating allyl radical. The obtained copolymer, therefore, was readily converted to the gelled polymer with methods such as heating and treating with Lewis acids or amines. Further, the copolymer containing two kinds of methylene groups was prepared similarly from methoxyallene ( II ) and AN, and was also converted to the crosslinked polymer with the cationic catalyst. These copolymers of I or II with AN will be expected to be new types of reactive polymers.     

磁性高分子微球

对磁性高分子微球的研究现状进行了综述,详细探讨了目前常用的各种合成制备方法,并对各种方法的优缺点进行了分析。在此基础上,对磁性高分子微球在细胞分离、有机合成、环境/食品微生物检测等领域的最新应用进展及存在的问题进行了分析,指出了该领域今后的研究方向。     

Kinetics and mechanisms of o/w microemulsion polymerization of styrene

To clarify the kinetics and mechanisms of o/w microemulsion polymerization, the o/w microemulsion polymerizations of styrene were carried out with different kinds and types of initiators and surfactants. The number of polymer particles and the molecular weight of polymer formed were not affected by the kinds and types of initiators and surfactants. The rate of polymerization with different kinds of azo-type oil-soluble initiators with widely different water-solubility was almost the same, but was much lower than that with KPS. A kinetic model proposed by us could mostly explain the kinetic behavior except for the difference in the polymerization rate with KPS and that with oil-soluble initiators.     

简并基态高分子的极化

在基态非简并 (Non degenerategroundstate ,NDGS)的高分子中 ,非简并的两个态的能量差导致了自陷激子 (Self trappedexciton ,STE)和自陷双激子 (Self trappedbiexciton ,STB) .由于自陷双激子的极化率是负的 ,基态非简并的高分子中能产生光致极化反转 (Photoinducedpolarizationreversion ,PPR) .最近 ,合成出具有优良的发光性能的共轭高分子PDPA(双取代聚乙炔 ) ,这是一种具有简并基态的高分子 ,简并态之间没有能量差 ,激发态是孤子 反孤子对 (s - s) ,而不是自陷激子和自陷双激子 .本文将证明这种具有简并基态的高分子也能产生负极化和光致极化反转 .     

Ytterbium Coordination Polymer with Four Different Coordination Numbers：The First Structural Characterization of Lanthanide Phthalate Complex

The novel ytterbium coordination polymer is a t4wo-dimensional framework in which the central metal ions have four different coordination numbers and form four kinds of coordination poly-hedra,The four kinds of coordination polyhedra connect into infinite chains by sharing oxygen atoms.     

水泥混凝土中的高性能高分子界面活性剂

综述了高效减水剂、高效引气减水剂等添加剂型高性能高分子界面活性剂在水泥混凝土中的种类和应用研究进展,对水泥混凝土中的有机硅氟高分子表面活性剂也做了简要的概述。     

端基功能化聚合物的表面性能

综述了端基功能化聚合物表面结构与性能的最新研究进展.聚合物端基功能化是实现聚合物表面改性的一种有效技术.通过端基功能化可以精确控制聚合物表面功能基团的种类和数量,从而影响聚合物表面的化学结构与性能.重点论述了功能化端基在聚合物表面的离析现象和产生这一现象的原因,以及功能化端基对聚合物表面分子运动能力的影响.本文还介绍了近年来用于研究端基功能化聚合物表面的表征新技术,如SFG、NR、SSIMS等.对端基功能化聚合物表面的环境响应性也进行了阐述.指出了利用不同功能化端基可以有效地控制聚合物表面的亲疏水性.并对端基功能化聚合物的应用进行了展望.     

Advancement of light-element neutron depth profiling at the University of Texas

The University of Texas (UT) at Austin has collaborated with the National Institute of Standards and Technology for comparisons of concentration versus depth profiles of samples containing ¹⁰B. Technology sharing from NIST has allowed UT to avoid many initial set backs such that significant advancements in the UT-NDP facility’s experimental and analytical methodology have been achieved. UT has analyzed two samples loaned to them from NIST. The collaborative effort between the two institutions has given the UT-NDP facility the proper tools to begin profiling more advanced samples in hopes of meeting the capabilities set by NIST in the NDP field. The UT-NDP facility was able to profile a borosilicate surface deposit onto silicon such that the concentrations of ¹⁰B at various depths of the deposit were determined and fit well to a Pearson distribution.     

石墨烯在聚合物阻燃材料中的应用及作用机理

本文从聚合物基底的阻燃复合材料类别角度出发,详细介绍了石墨烯在不同种类聚合物阻燃材料中的应用现状与作用机理。 包括有:石墨烯/聚乙烯、石墨烯/聚丙烯、石墨烯/聚苯乙烯、石墨烯/环氧树脂、石墨烯/聚氨酯、石墨烯/聚乙烯醇等多种石墨烯/聚合物复合阻燃材料。 同时还介绍了石墨烯基材料在其中所发挥的作用,该综述为发展出新型的石墨烯基/聚合物复合阻燃材料提供了很好的理论支持。     

聚丙烯酰胺凝胶结构非均匀性的动态光散射研究

利用动态光散射技术研究了聚丙烯酰胺 (PAAm)凝胶结构的非均匀性 ,分析了PAAm凝胶结构非均匀性的形成原因及凝胶动态光散射的数据处理方法和分析结果的物理意义 .研究结果表明 ,PAAm凝胶中含有动态相关长度 (LC)不同的两相 ,其中 ,LC 为 10～ 2 0nm的区域是聚合物稀疏相 ,LC 为 85nm左右的区域是聚合物密集相 ,两相的不均匀分布形成了PAAm凝胶结构的非均匀性 .分析表明 ,PAAm凝胶存在两相主要是由于单体和交联剂的溶解度存在差异所致 .随交联度增大 ,PAAm凝胶结构的非均匀性显著增强     

聚合物纳米管研究进展

全面综述了聚合物纳米管的制备方法及研究现状。根据聚合物纳米管的制备机理和实施方法的不同 ,可分为三类 :(1)多孔模板法 ;(2 )线模板法 ;(3)自组装法。详细总结了各种方法制备聚合物纳米管的研究成果 ,展望了制备聚合物纳米管新技术的开发前景和聚合物纳米管的应用前景     

Polymer types regulation strategy toward the synthesis of carbonized polymer dots with excitation-wavelength dependent or independent fluorescence

Three kinds of carbonized polymer dots (CPDs) synthesized via a one-pot process from o-phenylenediamine (OPD), m-phenylenediamine (MPD) and p-phenylenediamine (PPD) exhibit excitation-wavelength independent yellow, green and red emissions, respectively. In sharp contrast, two kinds of CPDs prepared via a hydrothermal process from citric acid (CA) and diethylenetriamine (DETA) exhibit obvious excitation-wavelength dependent emissions. Through the characterization and comparison of the two types of CPDs, it is concretely revealed that the polymer structure types during the formation of CPDs can effectively control the fluorescence excitation-wavelength independence/dependence. The homogeneous polymer structures contained in CPDs contribute to excitation-wavelength independence, whereas random copolymer structures contribute to excitation-wavelength dependence. These studies are of great significance for further understanding the polymer structures and designing unique optical properties of CPDs.     

Electron-transfer polymers. XXXIX. Redox polymers based on duroquinonyl glycol

Redox polyurethanes, polyesters, and alternate copolyurethanes and copolycarbonates from two kinds of benzoquinonyl glycol were prepared based on 2-(duroquinonyl)-propan-1,3-diol. The oxidized polymer is stable. When the fully reduced polymer in solution is exposed to air the durohydroquinonyl residues are oxidized to the quinone form while the less substituted hydroquinonyl glycol residues remain stable in the reduced form. There is thus prepared polymer with oxidized and reduced groups alternating along the chain.     

Unified theory of the exciplex formation/dissipation

The natural extension and reformulation of the unified theory (UT) proposed here makes it integro-differential and capable of describing the distant quenching of excitation by electron transfer, accompanied with contact but reversible exciplex formation. The numerical solution of the new UT equations allows specifying the kinetics of the fluorescence quenching and exciplex association/dissociation as well as those reactions' quantum yields. It was demonstrated that the distant electron transfer in either the normal or inverted Marcus regions screens the contact reaction of exciplex formation, especially at slow diffusion.     

单分散大粒径聚合物微球的合成及应用

单分散，大粒径聚合物微球是近２０年来开发的一类球形高分子粒子，在标准计量、情报信息、化学化工、医学免疫及生物化学等许多领域里有着广阔的应用前景，其合成和应用在高分子科学领域里已成为人们致力于研究和开发的热门课题。