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91.
92.
介绍了钛材碱洗脱脂除油和酸洗除去氧化皮的原理和方法,重点阐述了钛材碱洗除油和酸洗除去氧化皮的工艺条件、工艺流程和设备. 相似文献
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94.
Yuntao Dai Jaap van Spronsen Geert-Jan Witkamp Robert Verpoorte Young Hae Choi 《Analytica chimica acta》2013
Developing new green solvents is one of the key subjects in Green Chemistry. Ionic liquids (ILs) and deep eutectic solvents, thus, have been paid great attention to replace current harsh organic solvents and have been applied to many chemical processing such as extraction and synthesis. However, current ionic liquids and deep eutectic solvents have still limitations to be applied to a real chemical industry due to toxicity against human and environment and high cost of ILs and solid state of most deep eutectic solvents at room temperature. Recently we discovered that many plant abundant primary metabolites changed their state from solid to liquid when they were mixed in proper ratio. This finding made us hypothesize that natural deep eutectic solvents (NADES) play a role as alternative media to water in living organisms and tested a wide range of natural products, which resulted in discovery of over 100 NADES from nature. In order to prove deep eutectic feature the interaction between the molecules was investigated by nuclear magnetic resonance spectroscopy. All the tested NADES show clear hydrogen bonding between components. As next step physical properties of NADES such as water activity, density, viscosity, polarity and thermal properties were measured as well as the effect of water on the physical properties. In the last stage the novel NADES were applied to the solubilization of wide range of biomolecules such as non-water soluble bioactive natural products, gluten, starch, and DNA. In most cases the solubility of the biomolecules evaluated in this study was greatly higher than water. Based on the results the novel NADES may be expected as potential green solvents at room temperature in diverse fields of chemistry. 相似文献
95.
Antonio Calvo-López Eva Arasa-Puig Mar Puyol Joan Manel Casalta Julián Alonso-Chamarro 《Analytica chimica acta》2013
The construction and evaluation of a Low Temperature Co-fired Ceramics (LTCC)-based continuous flow potentiometric microanalyzer prototype to simultaneously monitor the presence of two ions (potassium and nitrate) in samples from the water recycling process for future manned space missions is presented. The microsystem integrates microfluidics and the detection system in a single substrate and it is smaller than a credit card. The detection system is based on two ion-selective electrodes (ISEs), which are built using all-solid state nitrate and potassium polymeric membranes, and a screen-printed Ag/AgCl reference electrode. The obtained analytical features after the optimization of the microfluidic design and hydrodynamics are a linear range from 10 to 1000 mg L−1 and from 1.9 to 155 mg L−1 and a detection limit of 9.56 mg L−1 and 0.81 mg L−1 for nitrate and potassium ions respectively. 相似文献
96.
3D打印技术制备生物医用高分子材料的研究进展 总被引:1,自引:0,他引:1
3D打印技术能够根据不同患者需要,快速精确制备适合不同患者的个性化生物医用高分子材料,并能同时对材料的微观结构进行精确控制.因此,这种新兴的医用高分子材料制备技术在未来生物医学应用(尤其是组织工程应用)中具有独特的优势.近年来,对于3D打印技术制备生物医用高分子材料的研究开发受到了越来越多的关注.不同的生物相容高分子原料被应用于3D打印技术,而这些3D成型高分子材料被用于体外细胞培养,或动物模型的软组织或硬组织修复中.本文主要介绍了近年来3D打印技术在生物医用高分子材料制备中的研究进展,并对该领域的未来应用和挑战进行了展望. 相似文献
97.
为实现对循环水水质的远程监测,设计并开发了一种基于嵌入式技术的热力站远程水质监测系统的监测终端。监测终端由水质传感器、GPRS模块、通信转换模块及嵌入式开发板组成。嵌入式开发板以ARM11系列的Tiny6410为硬件基础,并嵌入WinCE系统作为软件平台,同时加入SQLite数据库以实现将水质传感器采集到的氯离子、PH值、溶解氧等参数的本地存储、查询及图表显示。最后监测终端通过GPRS模块与数据中心建立无线连接,接收数据中心的配置命令,并将现场测得数据发送到远端数据中心。调试结果表明:远程监测终端实现了循环水水质远程监测的功能要求,对于实现水质自动化监测具有一定的理论意义和实用价值。 相似文献
98.
Qing Liu Lin Wang Zhuoheng Zhou Qiuquan Wang Lijuan Yan Bo Zhang 《Electrophoresis》2014,35(6):836-839
CEC is a high performance electrodriving liquid phase separation technique. It does not need complex and sophisticated high pressure instrumentation for nanoflow driving. This is attractive for parallel multicolumn analysis. To this end, high throughput methods for column preparation are needed to support the use of multiple columns. In this study, we directly used CEC mobile phase solution as the packing solvent, and realized rapid preparation of capillary columns based on a single particle fritting technology. The method presented high preparation throughput compared with other reported methods based on various fritting technologies. The single particle fritting approach promoted column preparation throughput to 1 column/h, including all the fritting, packing and conditioning steps. The rapidly prepared columns showed consistently high efficiency of up to 150 000 plates per meter, and usefulness in reversed phase CEC of neutral, charged and biomolecules. With standard peptides as the sample, excellent long term reproducibility (better than 0.8%RSD, ten days, for retention times) was observed. 相似文献
99.
针对物质结构教学的抽象性,开发了一套基于三维虚拟技术的物质结构教学软件,可对结构模型进行旋转、平移、缩放、切割、镜像、插入或删除原子(团)及启停预先设置的动画等操作,强大的交互功能不仅能对分子或晶体结构如构造异构、立体异构、晶体的堆积方式、晶胞的划分、配位数、晶体结构中的空隙及空间利用率等问题进行效果极佳的可视化教学,另一方面,通过对B12与C60分子空间构型转变的探究揭示数学构型的重要性,通过对六方晶胞占有原子个数的探究修正晶胞模型,通过对金属晶体的4种基本堆积方式成因的探究提出“半密置层”概念来完善紧密堆积规律等案例,展示出三维虚拟技术在微观结构探索发现方面的巨大潜力。 相似文献
100.
Membrane technology is of particular significance for the sustainable development of society owing to its potential capacity to tackle the energy shortage and environmental pollution. Membrane materials are the core part of membrane technology. Researchers have always been pursuing predictable structures of advanced membrane materials, which provides a possibility to fully unlock the potential of membranes. Covalent organic frameworks(COFs), with the advantage of controllable pore microenvironment, are considered to be promising candidates to achieve this design concept. The customizable function of COF membranes through pore engineering does well in the enhancement of selective permeability performance, which offers COF membranes with great application potentials in separation and transportation fields. In this context, COF-based membranes have been developed rapidly in recent years. Herein, we present a brief overview on the strategies developed for pore engineering of COF membranes in recent years, including skeleton engineering, pore surface engineering, host-guest chemistry and membrane fabrication. Moreover, the features of transmission or separation of molecules/ions based on COF membranes and corresponding applications are also introduced. In the last part, the challenges and prospects of the development of COF membranes are discussed. 相似文献