化学沉淀法制微细SiO2粉末

采用正交分析法研究以硅酸钠和盐酸为原料,用化学沉淀法制备微细SiO2粉末过程中反应温度、乙醇/水体积比、HCl浓度等影响因素对产品质量的影响,并利用粒度分析仪和金相显微镜对产品的粒度和形貌进行测试.实验结果表明在反应温度40℃,乙醇/水体积比为0.5,盐酸浓度为1.4 mol/L条件下制得的SiO2粉末,其粒径小且颗粒分散均匀.     

纤维素-二氧化硅复合颗粒的制备与表征

探索了可用作色谱填料的纤维素-SiO2复合颗粒的制备方法,将纤维素和硅胶溶于NaOH／尿素体系中,得到纤维素-SiO2溶液,用溶胶一凝胶转相法制得复合颗粒．研究了乳化剂用量、搅拌转速、纤维素分子量以及纤维素和SiO2的投料比对所制备的复合颗粒粒径和形貌的影响,以扫描电镜、粒径分析等对复合颗粒进行了表征．发现粘度小的分散相和分子量小的纤维素适合制备粒径大的复合颗粒,反之亦然．当纤维素与SiOz的投料比大于3：1时,复合颗粒呈球形,小于3：1时,多数颗粒的形状为无定形;当乳化剂Span80的用量为10％,搅拌转速为600r／min时,复合颗粒的形状较规则．在不同的条件下,所制备颗粒的体积平均粒径为9～45μm,比表面积在110～4802／g之间．调节乳化剂用量、搅拌转速、纤维素分子量以及纤维素与SiO2的投料比,能制备出粒径适当、比表面积大的复合颗粒,这些颗粒具有介孔结构,且孔径分布较均匀,机械强度高,适合用作色谱分离填料．     

An investigation of colour appearance for unrelated colours under photopic and mesopic vision

Data were obtained for the colour appearance of unrelated colours under photopic and mesopic conditions. The effects of changes in luminance level and stimulus size were investigated. The method used was magnitude scaling of brightness, colourfulness, and hue. Two stimulus sizes (10° and 0.5°) and four starting luminance levels (60, 5, 1, and 0.1, cd/m²) were used. The results at 0.1 cd/m² had large variations, so data were obtained for two additional stimulus sizes (1° and 2°) at this luminance level. Ten observers judged 50 unrelated colours. A total of 17,820 estimations were made. The observations were carried out in a completely darkened room, after 20 min adaptation; each test colour was presented on its own. Brightness and colourfulness were found to decrease with decreases of both luminance level and stimulus size. The CAM97u model predicted brightness more accurately than CIECAM02 but gave worse performance in predicting colorfulness. For hue, CAM97u and CIECAM02 both gave satisfactory predictions. Using the brightness correlate from CAM97u, a new colour‐appearance model based on CIECAM02 was developed specifically for unrelated colours under photopic and mesopic conditions, with parameters to allow for the effects of luminance level and stimulus size. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2011;     

珊瑚姜的超临界CO2萃取及其提取物GC/MS分析

用超临界CO2萃取技术对珊瑚姜进行提取分离,通过正交试验确定了最佳萃取工艺条件,即萃取时间150 min、萃取温度45℃、萃取流速20 L/h、萃取压力25 MPa。用气相色谱/质谱(GC/MS)联用仪对提取物成分进行了分析,共检测出38种化合物。超临界CO2萃取珊瑚姜方法简便、快速、高效,操作温度低,不破坏热敏性成分,无溶剂残留。     

Testing the performance of CIECAM02 from 100 to 3500 cd/m2

Color appearance models were developed to characterize the color attributes of stimuli under different viewing conditions based on data collected through magnitude estimation or color matching experiments. Although human beings experience very high light levels under daylight and the reproduction of colors under daylight is important in the color and imaging industries, the existing color appearance models were developed based on the data that were collected under the conditions with luminance levels below 700 cd/m² due to the lack of facilities to produce stable illumination at high light levels. A recent study investigating color preference of an artwork under a wide range of light levels from 20 to 15 000 lx suggested that CIECAM02 cannot accurately characterize the color appearance under extremely high light levels. This study was designed to directly test the performance of CIECAM02 from 100 to 3500 cd/m². Human observers performed color match for four hues under a series pairs of adapting conditions with a haploscopic viewing condition. It was found that CIECAM02 had the best performance in characterizing the hue angles but the worse performance in characterizing the brightness with a maximum underprediction around 200% across a wide range of luminance. This was mainly due to the fact that CIECAM02 was developed based on the data collected under relatively low adapting luminance levels. The color appearance model that was proposed to use the adapting luminance levels in characterizing the cone compression in the postadaptation process was found to have a much better performance in characterizing the brightness.     

CAT02 and HPE triangles

Here, we investigated the CAT02 and HPE triangles in both x,y and u′,v′ spaces. It was found that in u′,v′ space, the HPE triangle is separated into two regions by the line 3u′ ? 8v′ + 6 = 0, which is the u′,v′ image of X + Y + Z = 0 under the mapping from (X,Y,Z) to (u′,v′). One of these two regions admits all‐positive R,G,B triplets and the other all‐negative R,G,B triplets, under the case of (X + Y + Z) > 0. The findings of this study explained the computation problems of CAT02 and provided methods for solving the Yellow‐Blue and Purple problems simultaneously. © 2013 Wiley Periodicals, Inc. Col Res Appl, 40, 30–39, 2015     

应用大气污染估算模式分析解决空分装置CO2污染

通过借鉴环境影响评价方法,应用大气污染估算模式对不同排放方式下CO2落地浓度进行计算及对比分析,确认空分装置CO2污染源,找出低成本消除污染的方法。     

Trivalent chromium removal from tannery effluent using kaolin‐supported bacterial biofilm of Bacillus sp isolated from chromium polluted soil

BACKGROUND: Bacterial strains belonging to the genus Bacillus, isolated from Cr‐ polluted soil (tannery sludge) were employed as consortium for Cr(III) removal from tannery effluents. Kaolin clay, a natural adsorbent, was used as supporting material for bacterial biofilm formation. The use of clay‐supported bacterial biofilm has not previously been employed for the treatment of tannery effluents containing Cr(III) salt. RESULTS: Commercial tannery effluent containing 1000 ppm initial metal ion concentration was treated in stages. The initial Cr(III) concentration of 1000 ppm was brought down to 2 ppm, a permissible level for discharge, after the fourth stage. The bacterial isolates were found to be Bacillus subtilis VITSCCr01 and Bacillus cereus VITSCCr02 by 16s rRNA gene sequencing. Batch assay and confocal laser scanning microscopy results revealed the role of kaolin as a support material in biofilm formation. Best fit was obtained with the Freundlich adsorption isotherm. The mechanism of sorption was confirmed by Fourier transform infrared (FT‐IR) spectroscopy and scanning electron microscopy–energy dispersive X‐ray spectroscopy (SEM‐EDS). CONCLUSION: Cr(III) removal from tannery effluent using low cost adsorbents such as kaolin and bacteria proved to be effective for metal concentrations ?1000 ppm; this is normally not possible using conventional treatment methods. This work has demonstrated feasible sorption of Cr(III), especially during post‐tanning operations. Copyright © 2011 Society of Chemical Industry     

醋糟酶解液的制备及其发酵生产枯草芽孢杆菌TS-02

采用水热处理技术对醋糟进行预处理,优化了醋糟的纤维素酶酶解条件,制得葡萄糖浓度27.00 g/L的醋糟酶解液. 以醋糟酶解液为基础培养基替代培养基中的葡萄糖,发酵生产枯草芽孢杆菌TS-02活菌制剂. 结果表明,在醋糟酶解液培养基中摇瓶发酵44 h时活菌数活菌数最高达4.64×1010个/mL, 7 L发酵罐中发酵周期为22 h,活菌数达6.16×1010个/mL,芽孢率达80%以上.     

A comprehensive model of colour appearance for related and unrelated colours of varying size viewed under mesopic to photopic conditions

CIE has recommended two previous appearance models, CIECAM97s and CIECAM02. However, these models are unable to predict the appearance of a comprehensive range of colours. The purpose of this study is to describe a new, comprehensive colour appearance model, which can be used to predict the appearance of colours under various viewing conditions that include a range of stimulus sizes, levels of illumination that range from scotopic through to photopic, and related and unrelated stimuli. In addition, the model has a uniform colour space that provides a colour‐difference formula in terms of colour appearance parameters. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 293–304, 2017