超临界CO_2萃取芹菜籽油研究

用超临界ＣＯ２萃取技术对广东白芹菜籽进行了萃取研究。结果表明，萃取压力低于１５ＭＰａ时，较重的油树脂等成分难以被萃取出来；萃取温度为３０８Ｋ时对萃取最有利；解析温度对萃取效率影响较小；ＣＯ２流量对萃取效率的影响比床层高度引起的扩散阻力的影响大得多。超临界ＣＯ２萃取所得芹菜籽油品质优越，且其中的药用有效成分（３－正丁基－４，５－二氢苯并呋喃酮）含量比水汽法所得芹菜籽油的高五倍多。     

Synthesis of nano B2O3/TiO2 composite material as a new solid phase extractor and its application to preconcentration and separation of cadmium

A new solid phase extractor, nano-scale diboron trioxide/titanium dioxide composite material, was synthesized and used for separation and/or preconcentration of trace cadmium ion from various samples. The characterization of the synthesized material was performed by scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffractometer methods (XRD). The specific surface area of the material was also determined and found as 3.4 m²/g. Analytical parameters including pH of sample solution, sample volume, flow rate of sample solution, volume and concentration of eluent for the column solid phase extraction (SPE) procedure were examined. The effect of common matrix ions on the recovery of the cadmium has also been investigated and found that they did not interfere on cadmium preconcentration. Under the optimum experimental conditions, preconcentration factor and analytical detection limit were determined as 50 and 1.44 μg/L, respectively. The reusability (stabile up to 100 run) and adsorption capacity (49 mg/g) of the sorbent were excellent. The accuracy of the method was confirmed by analyzing certified reference materials (Tea leaves GBW-07605). The results demonstrated good agreement with the certified values (relative error <10%). The precision of the method was also satisfactory. The recovery of cadmium under the optimum conditions was found to be 96 ± 3% at 95% confidence level. The method was applied for the determination of cadmium in tap water and tea leaves.     

CeO_2掺杂TiO_2催化超声降解酸性大红的研究

选取酸性大红染料为降解目标物,研究了用实验室合成的氧化铈掺杂二氧化钛为催化剂存在下的超声反应。研究结果表明,CeO2掺杂TiO2催化超声降解酸性大红的效果优于非掺杂的锐钛矿型TiO2的情况。在溶液pH1.0～3.0、酸性大红质量浓度为20mg/L、溶液用量50mL、催化剂用量0.5～1.0g/L的条件下,用输出功率5.0W/cm2和频率25kHz的超声波照射80min,酸性大红降解率可达97.3%。     

Methanation of carbon dioxide over Ru/Titania at room temperature: explorations for a photoassisted catalytic reaction

The methanation of CO₂ has been investigated over a special Ru/TiO₂ catalyst suggested by Thampi, Kiwi and Graetzel [4]. This paper deals with the analysis of the material and the investigation of the reported photoenhancement of the activity. The catalyst is characterised by in situ UV-VIS spectroscopy and by XPS. Conversion experiments at atmospheric pressure were carried out with and without UV light irradiation. The irradiation increases the conversion significantly. From various experiments it can be shown, however, that this effect is due to a thermal effect and does not involve an intrinsic photochemical step. Localised Ti³⁺ states sensitise the support to convert visible light into heat resulting in the observed increase in conversion.     

反胶团在超临界CO_2萃取中的应用

近年来超临界流体萃取技术倍受人们青睐,超临界CO2作为有机溶剂的替代者促进了绿色工艺的发展。对于相对分子质量大的或亲水性分子及金属离子,CO2并不是一种好溶剂。采用反胶团体系可解决这一难题并开发许多新的工艺。本文概述了超临界CO2中反胶团技术的发展概况,重点阐述了反胶团在超临界CO2萃取中的应用。     

夹带剂和鞣制时间对二氧化碳超临界流体条件下铬鞣的影响

利用自制的二氧化碳超临界流体制革设备,考察了夹带剂A用量和鞣制时间,对二氧化碳超临界流体代替水 作介质铬鞣的影响。通过对鞣制后坯革的收缩温度、铬含量和感观等的比较,得出了二氧化碳超临界流体条 件下,铬鞣夹带剂A最佳用量为8%,最佳鞣制时间为1h。     

超临界二氧化碳染色技术研究进展

概述了超临界二氧化碳染色技术的染色机理,对不同染料的染色工艺条件的研究情况做了分析。阐述了染料研究和混合染料拼色研究的进展情况。对超临界二氧化碳的染色热力学和动力学性研究情况做了论述,对染料在超临界二氧化碳中的溶解度、染料在纤维与超临界CO2间的分配规律、染料在纤维中的扩散行为做了分析论述。对染色设备的国内外进展情况做了分析论述。指出了超临界二氧化碳染色技术产业化应用应解决的关键问题是增强染料的溶解和在纤维中的扩散,以及高压操作下大容积染色釜的研制。     

食品添加剂二氧化碳中苯气体标准物质性能评价方法的研究

介绍了食品添加剂二氧化碳中苯气体标准物质的分析方法和性能评价方法。采用美国Agilent6890N气相色谱仪、FID检测器,在最佳色谱实验条件下对苯的检测限小于10×10^-9,线性误差小于2%。还给出了二氧化碳中苯气体标准物质均匀性、一致性、稳定性（随时间、压力变化）的考察结果。研究成果表明二氧化碳中苯气体标准物质重量配制的相对扩展不确定度小于1.7%。     

食用菌等生鲜食品液态N2和CO2深冷冻结技术

介绍了食用菌等生鲜食品速冻技术的最新研究进展与应用情况,就速冻食用菌等生鲜食品加工技术的方法、设备、冻结与冻藏工艺进行综述,并对食用菌等生鲜食品的开发利用前景进行了展望。