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1.
本文通过使用便携式拉曼光谱仪来快速检测废水中残留有机溶剂的种类和含量。首先利用便携式拉曼光谱仪建立标准拉曼谱图库,然后用便携式拉曼光谱仪检测废水样品并与标准谱图库比对,即可获得废水中含有的有机溶剂的种类和含量。该方法简便、灵敏、快速,对于实时监测废水的排放具有重要意义。  相似文献   

2.
采用表面增强拉曼光谱法快速检测水果中的农药残留噻菌灵。水果样品经提取、净化、萃取和表面增强后,使用岛津便携式拉曼光谱仪RM-3000测试可获得满意的检出信号,整个分析过程在45min内即可完成,样品和试剂使用量少,检出浓度低,可适用于水果中农残噻菌灵的快速筛查检测。  相似文献   

3.
综合利用便携式X射线荧光光谱仪(pXRF)、激光Raman光谱仪(便携式和可移动式)以及光学相干层析成像(OCT)技术,对河南出土的14件东周玉器进行无损分析测试。pXRF和便携式微型Raman光谱仪(miniRaman)能够准确、快速的识别玉器的原材料和物相。且这两台仪器操作简单、体积小,可用于做现场原位、无损分析。根据pXRF检测结果,这批玉器按成分可分为富硅铝钾、富钙、富硅、富硅镁、富硅钙和富钙磷6大类。通过miniRaman快速地鉴定出这批样品的主要物相。在实验室里,使用可移动式共焦激光Raman光谱仪,可以弥补便携式微型Raman光谱仪在光谱分辨率、测量精度以及测量范围等方面的不足。利用共焦激光Raman光谱仪,检测到透闪石型玉器中[OH]根的Raman振动峰。OCT技术可以分析玉器材质的透明度、纤维粗细程度、包裹体分布等亚表面特征。将共焦激光Raman光谱仪与OCT分析仪有机结合分析了两件含包裹体的透闪石玉器样品,OCT图像可以直观地展示这两件样品中的包裹体分布特征,而共焦激光Raman光谱仪可以准确定位样品表面的包裹体,进行显微形貌观察及其物相分析,结果表明黑色的包裹体为石墨,这对玉器的产地溯源研究具有重要意义。通过研究发现,利用便携式X射线荧光光谱仪,激光Raman光谱仪和光学相干层析成像技术 ,可以实现对文物样品的物相组成和质地特征进行初步鉴别和分析,满足考古工作的现场基础分析要求。  相似文献   

4.
冶金炼钢要求快速分析冶金炉前样品来及时掌握冶炼过程。文章介绍了自主研制的一种新型的光谱仪——激光诱导击穿光谱仪,该仪器采用ns级脉宽的Nd∶YAG激光器作为样品离子化光源,激光聚焦样品表面激发产生的等离子体光谱依次经帕邢-龙格光学系统进行分光、光电倍增管探测、门控积分器积分、模拟数字转换器转换后获得的最终结果输入计算机进行数据处理。和目前冶金炉前样品分析常用的光谱仪相比,该仪器无需样品预处理,分析速度快(1 min或更少),准确灵敏度高,非常适用于冶金炉前样品的快速分析。近年来随着光纤技术的迅速发展,使用该仪器进行钢液实时在线分析和动态控制冶金工艺必将成为现实。  相似文献   

5.
便携式X射线荧光光谱仪快速监测重金属土壤环境质量   总被引:8,自引:0,他引:8  
便携式X射线荧光光谱仪(PXRF)作为一种新型快速测试手段具有突出的应用前景,但也存在检测范围和检测限的局限,为此本文研究PXRF仪器在快速监测土壤环境质量中Cr,Ni,Cu,Zn,Pb,Cd,As和Hg等8种重金属元素的适用性,筛选仪器可检测元素,评价检测结果准确度。具体方法是使用仪器测试重金属污染土壤样品,测试结果与电感耦合等离子体质谱分析方法(ICP-MS)测试值进行对比,评判检测结果精密度,建立PXRF仪器测试值与ICP-MS仪器测试值的线性回归关系。结果表明:(1)在监测重金属土壤环境质量时,PXRF仪器可用于检测土壤中Pb,Zn,Cr和Cu含量,但不适于检测Ni,Cd,As和Hg含量。(2)Pb和Zn测试值稍低于ICP-MS测试值,Cu偏高,而Cr过高;PXRF仪器测试值需要参照标准分析方法进行线性校正。研究结论为:便携式X射线荧光光谱仪适用于Pb,Zn,Cr和Cu等4种重金属的土壤环境质量监测,是一种简单快速、准确可靠的低成本土壤重金属分析手段。该研究的创新之处是合理规避PXRF仪器的缺点,将仪器应用于土壤环境质量监测,提高了测试结果应用价值。  相似文献   

6.
设计了海水中极低浓度营养盐在线测量仪,测量方法采用吸收光度法。采用长光程液芯波导作为样品池,光信号由光纤收集、光谱仪分光。线阵CCD探测器测量样品吸光度,可以实现多种营养要素的快速检测。检测极限达到了0.2 nmol/dm3;分液泵、注射泵、电磁阀及过滤网等构成了现场自动进样系统;电子学系统由PC104工控机、CCD数据采集卡及自动进样控制电路组成,实现了水样的提取及在线过滤、样品与试剂的精密配比和混合反应以及光谱测量及分析的自动化。该仪器不仅可用来作为剖面测量,而且也可用于定点长时间序列测量。  相似文献   

7.
利用自主研发的便携式拉曼光谱仪对13种常见的易制毒化学品做了现场分析。通过改变分析方法,如仪器的聚焦位置、分析时间、外部光源、样品装载容器、分析物的浓度,以得到高质量的易制毒化学品拉曼散射谱图。结果表明:优化的分析方法能改善检测效率,另外1-苯基-2-丙酮、甲苯、三氯甲烷有较低的极限检测浓度,混合物的组分含量对检测结果有很大影响。选择合适的仪器工作条件,能更有效地、快捷地现场筛选易制毒化学品,有助于禁毒工作者的实战检测。  相似文献   

8.
便携式X射线荧光光谱仪(PXRF)作为一种新型快速测试手段具有突出的应用前景,但也存在检测范围和检测限的局限,为此本文研究PXRF仪器在快速监测土壤环境质量中Cr,Ni,Cu,Zn,Pb,Cd,As和Hg等8种重金属元素的适用性,筛选仪器可检测元素,评价检测结果准确度。具体方法是使用仪器测试重金属污染土壤样品,测试结果与电感耦合等离子体质谱分析方法(ICP-MS)测试值进行对比,评判检测结果精密度,建立PXRF仪器测试值与ICP-MS仪器测试值的线性回归关系。结果表明:(1)在监测重金属土壤环境质量时,PXRF仪器可用于检测土壤中Pb,Zn,Cr和Cu含量,但不适于检测Ni,Cd,As和Hg含量。(2)Pb和Zn测试值稍低于ICP-MS测试值,Cu偏高,而Cr过高;PXRF仪器测试值需要参照标准分析方法进行线性校正。研究结论为:便携式X射线荧光光谱仪适用于Pb,Zn,Cr和Cu等4种重金属的土壤环境质量监测,是一种简单快速、准确可靠的低成本土壤重金属分析手段。该研究的创新之处是合理规避PXRF仪器的缺点,将仪器应用于土壤环境质量监测,提高了测试结果应用价值。  相似文献   

9.
用于食品安全、环境污染、毒品、化学战剂检测等的现场快速检测要求检测设备便携、快速和准确。目前的常规实验室检测方法虽然能够实现准确检测,但是其实时性较差,无法满足现场快速检测的要求。因此,设计开发了基于等离激元增强拉曼光谱的便携式快速检测仪,能够实现对滥用添加剂、违禁食品添加剂、农药残余、毒品、化学战剂和环境水污染等大量有害物质的现场快速定性检测。该检测仪基于ARM嵌入式系统开发,编写了其操作交互界面和底层驱动程序,实现了拉曼光谱数据自动标定和特征谱图快速识别等算法。在仪器中搭建了检测物质拉曼光谱的标谱数据库,数据库根据检测科目进行分类,每种科目包含该类别的多种物质,每种物质均包含其高中低多种浓度的标准品和样本谱图。设计实现了大类科目的辨识比对算法和GPU硬件加速算法,实现了对某一类科目的所有物质的快速比对,与传统的纯CPU算法实现相比较,在辨识速度上提高了20倍以上。通过市场购买的功能饮料、违规葡萄酒与果汁等实际样品对所制备的样机仪器进行测试,测试结果符合预期,具有良好的灵敏度与重现性,满足了现场快速检测的要求。  相似文献   

10.
文物保护与考古工作者最为关心的是从文物中无损提取各种有用信息,了解文物老化状况,以便采取合适的保护措施.文章选用桑蚕丝、书画和彩绘文物常用材料印章、胭脂、朱砂、朱膘国画颜料为样品,采用便携式拉曼光谱仪检测样品在紫外光辐照前后光谱变化,进行文物光老化研究.结果表明,在360 nm波长,照度0.68 w·m-2的紫外光下.蚕丝样品47 h发生明显降解现象;便携式拉曼光谱仪采集的光谱能清晰鉴别出印章印泥种类和来源,灵敏检测出印泥和其他国画颜料经163 h紫外辐照后发生氧化分解及颜料分子结构的变化.该工作为文物现场检测、研究实际环境因素对文物影响作用,为研究文物衰变规律提供了一种便捷检测手段.  相似文献   

11.
超声提取党参总皂苷的工艺   总被引:1,自引:0,他引:1  
优选党参总皂苷的最佳超声波提取工艺条件。采用正交试验设计优化党参总皂苷提取工艺的影响因素,通过比色法测定总皂苷含量,并与传统提取法进行比较。超声波强化提取总皂苷的提取工艺为甲醇提取,料液比1:20(g/mL),超声时间为30min,超声次数3次。方法操作简便、条件稳定,提高了药材的利用率,可用于党参总皂苷的提取。  相似文献   

12.
实验考察了超声、硝酸预处理、酸化程度、碱液浓度、反应温度、液固比、反应时间等对腐植酸提取率的影响,并通过正交设计选择最佳预氧化条件和褐煤腐植酸的最佳提取条件.结果表明;超声硝酸联合氧化法提取腐植酸的最佳条件为:超声频率80kHz,氧化温度50℃,硝酸液固比(mL/g)为5∶1,氧化时间90min,硝酸浓度1.5mol/L.  相似文献   

13.
建立了超声波辅助浸提-冷原子吸收光谱法测定化妆品中汞的方法,对样品前处理方法、样品取样量、盐酸羟胺、正辛醇及其他共存金属离子等影响因素进行了研究。该方法汞的检出限为0.012μg,加标回收率为87.5%—98.3%,该方法与国标方法对照,缩短了样品前处理时间且结果无显著性差异,为化妆品中汞的检测与质量控制提供了一种快速、准确的分析方法。  相似文献   

14.
土壤中无机砷测定的三种前处理方法比较   总被引:9,自引:1,他引:9  
对土壤无机砷分析的样品前处理技术-微波辅助提取、超声波提取、水浴提取进行了对比研究.结合氢化物发生-原子荧光光谱(HG-AFS)测定技术比较了3种方法对国家土壤标准物质中无机砷的提取效果,并对溶剂类型、提取时间和提取剂用量等影响因素进行了考察.与超声波提取法和水浴提取法相比,微波辅助提取法具有快速、高效的优势.  相似文献   

15.
Ma Y  Ye X  Hao Y  Xu G  Xu G  Liu D 《Ultrasonics sonochemistry》2008,15(3):227-232
Hesperidin, an abundant and inexpensive bioflavonoid in Penggan (Citrus reticulata) peel, has been reported to possess a wide range of pharmacological properties. Ultrasonic extraction is an effective technique for the isolation of bioactive compounds from vegetable materials. In this study, the application of ultrasonic method was shown to be more efficient in extracting hesperidin from Penggan (C. reticulata) peel than the classical method. The effects of main ultrasonic-assisted extraction conditions on extraction yields of hesperidin from Penggan (C. reticulata) peel were evaluated, including extraction solvents, solvent volume, temperature, extraction time, ultrasonic power, ultrasonic frequency. Results showed that solvent, frequency and processing temperature were the most important factors for improving the extracting yields of hesperidin. When performed at the same temperature under the same time using three frequencies, methanol as the solvent improved the extraction yield evidently compared with ethanol or isopropanol; by comparison of the frequency influence, the yield of hesperidin was higher at 60 kHz than at 20 kHz and 100 kHz. The optimum ultrasonic conditions were determined as: methanol, frequency of 60 kHz, extraction time of 60 min, and temperature of 40 degrees C. In addition, the ultrasonic power had a weak effect on the yields of hesperidin within the experimental range. Extending ultrasonic treatment times did not result in degradation of hesperidin; the rotary beaker for materials can increase the yields of hesperidin.  相似文献   

16.
In this study, microwave pretreatment and grinding treatment were used to enhance sulforaphane formation, then ultrasonic-assisted extraction (UAE) was applied to extract sulforaphane using simultaneous hydrolysis and extraction method. The effects of various parameters, which were ultrasonic time, ultrasonic power, solid-water ratio and solid-ethyl acetate ratio on the extraction rate of sulforaphane were investigated. The results showed that microwave pretreatment enhanced sulforaphane formation. Excessive size reduction did not increase or even reduced extraction rate of sulforaphane. Simultaneous hydrolysis and extraction significantly increased extraction rate of sulforaphane compared to hydrolysis followed by extraction. UAE accelerated mass transfer and the solubilization of the targeted compounds due to the acoustic cavitation effect, thus enhanced enzymatic hydrolysis of glucoraphanin and the extraction rate of sulforaphane. The extraction rate of sulforaphane using UAE with simultaneous hydrolysis and extraction was 4.07-fold of the conventional extraction method. UAE was an effective method to extract sulforaphane from broccoli seeds since it led to higher yield of sulforaphane in a much shorter extraction time.  相似文献   

17.
超声辅助法提取白筋茎皮总黄酮的工艺研究   总被引:1,自引:1,他引:0  
采用超声辅助法提取白霸茎皮中总黄酮化合物,通过单因素试验和正交试验,研究了超声提取条件(超声功率,乙醇浓度,料液比,时间)对其中总黄酮提取的影响。白筋茎皮总黄酮最佳提取工艺为:料液比1:30.乙醇浓度70%,超声功率120W,提取时间25min。在此工艺条件下提取,总黄酮含量为53.0843mg/g。  相似文献   

18.
郭婕  崔桂友 《光谱实验室》2010,27(1):335-339
利用超声提取的方法,通过单因素和正交实验分析了溶液浓度、超声时间、料液比、提取次数4个主要因素对总酚提取率的影响。确立了加拿大一枝黄花总酚的最佳提取工艺条件为:60%甲醇、超声50min、料液比1∶20、提取3次。在此条件下,总酚的提取率为44.61mg/g。  相似文献   

19.
In this study ultrasonic (US) pretreatment was investigated with the aim of improving the anaerobic digestion of sunflower oil cake (SuOC), the solid waste derived from the extraction process of sunflower oil. Five ultrasonic pretreatment assays were conducted at specific energy (SE) and sonication times in a range from 24,000 kJ/kg TS and 16.6 min (assay 1: US1) to 597,600 kJ/kg TS and 331.2 min (assay 5: US5), respectively, all operating at a constant sonication frequency (20 kHz) and ultrasonic power (120 W). As regards ultrasonic pretreatment, the working conditions of the first assay (US1) using samples of SuOC at 2% (w/v) showed to be the most appropriate in terms of both lignin and hemicellulose degradation (57.7% and 66.7%, respectively) and cellulose increase (54% increase with respect to its initial concentration). The percentage of COD solubilization increased from only 14% to 21% when SE was 25 times higher. Results obtained in batch anaerobic digestion experiments (biochemical methane potential - BMP - tests) conducted at 35°C of the solid and liquid fractions released from the different ultrasonic conditions tested, indicated that for the first experiment (US1) the average ultimate methane yield obtained was 53.8% higher than that achieved for untreated SuOC. Finally, the kinetic constants of the anaerobic digestion of the solid and liquid fractions released after the ultrasonic pretreatment were virtually independent of the operation conditions assayed.  相似文献   

20.
Low-frequency ultrasonics is a potential technology to reduce the hydrolysis phase period in anaerobic digestion process. In this study, the influence of combined low frequency ultrasonics and micro-aerobic (MA) pretreatment on sewage sludge solubilization, enzyme activity and anaerobic digestion were assessed. Initially, the effect of ultrasonic density (0.012, 0.014, 0.016, 0.018, 0.1, 0.12 and 0.14 W/mL) and irradiation time (1, 3, 5, 8, 9, 10 and 12 min) of 20 kHz frequency waves were investigated. Accordingly, the effect of micro-aerobic pretreatment (Air flow rate (AFR) = 0.1, 0.2, 0.3 and 0.5 VVM) within 20, 30, 40.48 and 60 h were examined. In addition, the effect of combined pretreatment on COD solubilization, lipase enzyme activation, ATP, percentage of live bacteria and methane gas production during the anaerobic process were examined. The results showed that the highest lipase activity (14.9 Umol/mL) was obtained under the effect of ultrasonic density of 0.1 W/ml within 9 min. The highest solubilization (65%) was observed under optimal micro-aerobic conditions: AFR = 0.2 (VVM) and micro-aerobic time: 40 h. Combined ultrasonic and micro-aerobic (US + MA) pretreatment increases the solubilization (70%), microbial activity (2080%) and lipase enzymatic activity (129%) compared to individual pretreatment. The Biogas production during anaerobic digestion pretreated with combined methods increased by 193% compared to the control, while the elevated values of biogas production in reactors pretreated by ultrasonic and micro-aerobic pretreatment alone were observed to be 101% and 165%, respectively. The net energy in reactor with the combined pre-treatment methods was calculated to be 1.26 kWh, while this value for control, pretreated ultrasonic and micro-aerobic reactors were obtained to be 0.56, 0.67 and 1.2 kWh, respectively.  相似文献   

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