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961.
962.
《Electrophoresis》2018,39(14):1754-1762
A novel and fully automated sequential injection analysis manifold coupled to a capillary electrophoresis apparatus with amperometric detection, is described. The sequential injection manifold was isolated from the high voltage by inserting an air plug into the circuit. Small buffer reservoirs were used to avoid the need to pump fresh buffer to the interface during the electrophoretic separation. No decoupling device was used to mitigate the interference from the high voltage electric field, instead the potential shift induced by the separation voltage, was accounted for. The new hydrodynamic injection method presented is based on the overpressure created in the circuit when a pinch valve is closed for a predetermined time. The injection method yields RSD values of peak height and area below 2.55 and 1.82%, respectively, at different durations of valve closure (n = 5). The capillary and working electrode alignment was achieved by adapting a commercial available capillary union. When the electrode was replaced, the alignment method proved to be very reliable, yielding RSD values of peak height and area lower than 2.64 and 2.08%, respectively (n = 8). Using this system with a gold microelectrode, dopamine, and epinephrine could be quantified within the concentration range of 1–500 μM and detected at a concentration of 0.3 μM. The methods here presented could be applied for the development of new capillary electrophoresis systems with amperometric detection and/or to the design of fully automated systems for online process monitoring purposes. 相似文献
963.
Thirupathi Ravula Nathaniel Z. Hardin Sudheer Kumar Ramadugu Sarah J. Cox Prof. Ayyalusamy Ramamoorthy 《Angewandte Chemie (International ed. in English)》2018,57(5):1342-1345
Polymer lipid nanodiscs are an invaluable system for structural and functional studies of membrane proteins in their near‐native environment. Despite the recent advances in the development and usage of polymer lipid nanodisc systems, lack of control over size and poor tolerance to pH and divalent metal ions are major limitations for further applications. A facile modification of a low‐molecular‐weight styrene maleic acid copolymer is demonstrated to form monodispersed lipid bilayer nanodiscs that show ultra‐stability towards divalent metal ion concentration over a pH range of 2.5 to 10. The macro‐nanodiscs (>20 nm diameter) show magnetic alignment properties that can be exploited for high‐resolution structural studies of membrane proteins and amyloid proteins using solid‐state NMR techniques. The new polymer, SMA‐QA, nanodisc is a robust membrane mimetic tool that offers significant advantages over currently reported nanodisc systems. 相似文献
964.
Hae-Chang Jeong Jonghoon Won Ju Hwan Lee Hyo-Young Mun Dong Hyun Kim Dong Wook Lee 《Liquid crystals》2018,45(1):95-101
We present the fabrication of an anisotropic structure on a polyurethane (PU) film for aligning liquid crystal (LC) molecules with ion beam (IB) irradiation at an incident angle. The obtained anisotropic structure assembles the LC cells in a layer that aligns LC molecules uniformly. Polarised optical microscopy images of an LC cell fabricated with IB-irradiated PU were captured to confirm the LC alignment state and compared with those fabricated with non-treated PU. To analyse the effects of the IB irradiation, X-ray photoelectron spectroscopy and field-emission scanning electron microscopy were used to investigate the chemical and morphological modifications, respectively. IB irradiation modifies the chemical structure of PU, which indicates that a new skin layer is formed on the PU films. This skin layer generates an in-plane compressive strain, thereby creating buckles on the PU films. Simultaneously, the physical collision of the reactive Ar+ ions during IB irradiation induces a directional strain on the surface, thereby forming a unidirectional structure of buckles along the direction of IB irradiation. The PU film annealed at 200°C showed the high average transmittance of 88.9%, which is appropriate as an alignment layer. 相似文献
965.
We synthesised a series of vitamin-based and renewable tocopherol-substituted polystyrene (PTOC#, # = 20, 40, 60, 80 and 100), where # is the molar content of tocopherol moiety, using polymer analogous reactions to investigate their liquid crystal (LC) alignment properties. In general, the LC cell fabricated using the polymer film having a higher molar content of tocopherol side group showed vertical LC alignment behaviour. The vertical alignment (VA) behaviour was well correlated with the surface energy value of these polymer films. For example, VA was observed when the surface energy values of the polymer were smaller than about 35.22 mJ/m2 generated by the nonpolar tocopherol moiety having long and bulky carbon groups. Good electro-optical characteristics, such as voltage holding ratio and residual DC voltage, and aligning stabilities at 200°C and ultraviolet irradiation of 10 J/cm2 were observed for the LC cells fabricated using PTOC100 as a LC alignment layer. Therefore, it was first found that the renewable tocopherol-based materials can produce an eco-friendly vertical LC alignment system. 相似文献
966.
本文讨论按生命周期方法开发大型软件的SA/SD自动转换技术,将知识引入转换工具,重点介绍三维十字链表的数据模型和转换过程中专家知识的组织和引用原则。 相似文献
967.
Kyu-Seog Hwang Hae-Am Park Byeong- Soojung Bo-An Kang Yun-Ho Kim 《Journal of Sol-Gel Science and Technology》2002,23(1):67-72
Bismuth titanate films were fabricated onto highly oriented LaNiO3 electrode grown on SrTiO3(100) and LaAlO3(012) substrates using spin-coating technique with metal naphthenates as starting materials. (00l)/(h00)-oriented bismuth titanate films on LaNiO3/SrTiO3 and LaNiO3/LaAlO3 were obtained by pyrolysis at 500°C, followed by annealing at 750°C. In-plane alignment and surface morphology of the films analyzed by pole-figure analysis ( scanning) and field emission scanning electron microscope showed an imperfect epitaxy with polycrystalline structure.An erratum to this article can be found at 相似文献
968.
纳米复合永磁材料晶粒择优取向的研究 总被引:4,自引:0,他引:4
利用熔体快淬技术制备把(Nd11.4Fe82.9B5.7)0.99M1(其中M=Zr,Nb,Ga,Zr Ga,Nb Ga)快淬带。发现Ga元素的添加对Nd2Fe14B相晶粒的C轴垂直于带面取向是有利的。复合添加Zr Ga或Nb Ga可获得较好的磁性能,并且进一步提高了快淬带晶粒的择优取向。取向度随厚度改变发生明显的变化,当带厚约为120μm时取向度最高。热处理可使淬带织构度增加,但导致晶粒粗化。利用深冷技术对纳米晶复合快淬带进行超低温处理。发现深冷处理有利于快淬带织构度的增强,且晶粒尺寸几乎不变。 相似文献
969.
970.
为建立简便、灵敏的双试剂自动化分析法测定血清未饱和铁结合力(UIBC),在表面活性剂存在下,用2-(5-溴-2-吡啶偶氮)-5-[(N,N-二羧基甲基)氨基]苯酚(5-Br-PADCAP)为显色剂测定血清UIBC。结果表明,线性范围0~90μmol/L,平均回收率101.57%,批内变异系数(CV)和批间变异系数分别为0.028、0.046,与日本和光UIBC测定试剂盒比较具有良好的相关性,线性回归方程和相关系数分别为y=1.0133x-0.3356,r=0.9961。108例健康人血清UIBC含量为31.65~50.81μmol/L(±2s)。用5-Br-PADCAP双试剂自动化分析法测定血清UIBC方法简便、灵敏可靠,适合临床应用。 相似文献