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11.
采用自行研制的电喷雾萃取电离源(EESI)与LTQ-XL质谱仪耦合,并结合主成分分析(PCA)和聚类分析(CA),建立了一种能在无需样品预处理的条件下直接、快速、准确鉴别茅台等八种掺假白酒(混掺水和工业酒精,且通过酒精计调控掺假酒的酒精度与真酒保持一致)的新方法. 同时,利用串联质谱能够对目标组分进行准确鉴定. 研究结果表明,EESI-LTQ-MS检测单个样品的时间小于1 min,且重现性好,PCA区分正确率高达96.5%. 通过设置未知样分析进一步验证了该方法的可行性. 此外,还结合单光子电离飞行时间质谱法(SPI-TOF-MS)对检测谱图进行对比分析. 阐述了EESI和SPI两种电离技术在挥发性有机物分析上具有各自的优势,且两种检测手段具有互补的特点. 为市场上酒类饮品真假的快速鉴别及品质鉴定建立了一个综合的分析方法,对于快速筛选伪劣酒类产品具有非常重要的应用价值. 相似文献
12.
Zhao-Bo Chen Zhi-Qiang ChenNan-Qi Ren Hong-Cheng WangShu-Kai Nie Min-Hua Cui 《Applied Mathematical Modelling》2012,36(1):173-182
In order to investigate the influence of mixed liquor inorganic suspended solids (MLISS) on membrane flux at different ratio of sludge retention time (SRT) to hydraulic retention time (HRT) in a submerged membrane bioreactor (SMBR), a pilot scale test was conducted for 452 days using traditional Chinese medicine (TCM) wastewater as influent. SRT/HRT was controlled at 150, 480 and 750, respectively. The experimental results showed that the average values of MLISS were 1271.9, 1664.5 and 6898.8 mg/L at different SRT/HRT, respectively; MLISS were accumulated from 265.5 g/h to 4912.93 g/h, which indicated that SMBR could not steadily operate for a long period without sludge withdrawal. Sludge oxygen utilized rate (SOUR) decreased from 5.115 to 1.292 mgO2/(gVSS h) and volume oxygen utilized rate (VOUR) increased from 10.84 to 18.13 mgO2/(L h). Model of membrane flux and MLISS were developed under different temperature and operational pressure by regressions, which were then satisfactorily employed to predict the trend of membrane flux during the experiment. 相似文献
13.
黏胶废液对福建无烟煤水蒸气催化气化的动力学和补偿效应 总被引:2,自引:0,他引:2
采用黏胶废液为催化剂,对福建尤溪无烟粉煤在常压热分析仪中的水蒸气催化气化动力学进行了研究。在850℃~950℃测定了黏胶废液催化剂添加量(NaOH浓度为计算基准)从0~12%时的碳转化率随气化时间的变化,表明黏胶废液具有提高碳转化率和气化速率的作用,同时确定了该黏胶废液催化剂的加载饱和浓度。基此得出的尤溪无烟粉煤水蒸气催化气化反应动力学符合缩芯模型,并给出相应的动力学参数。进而分析表明,该催化气化过程存在明显的补偿效应,最后给出黏胶废液对尤溪无烟粉煤水蒸气催化气化包括补偿效应的动力学方程。 相似文献
14.
Stephan Wasielewski Eduard Rott Ralf Minke Heidrun Steinmetz 《Molecules (Basel, Switzerland)》2021,26(1)
Sludge water (SW) arising from the dewatering of anaerobic digested sludge causes high back loads of ammonium, leading to high stress (inhibition of the activity of microorganisms by an oversupply of nitrogen compounds (substrate inhibition)) for wastewater treatment plants (WWTP). On the other hand, ammonium is a valuable resource to substitute ammonia from the energy intensive Haber-Bosch process for fertilizer production. Within this work, it was investigated to what extent and under which conditions Carpathian clinoptilolite powder (CCP 20) can be used to remove ammonium from SW and to recover it. Two different SW, originating from municipal WWTPs were investigated (SW1: c0 = 967 mg/L NH4-N, municipal wastewater; SW2: c0 = 718–927 mg/L NH4-N, large industrial wastewater share). The highest loading was achieved at 307 K with 16.1 mg/g (SW1) and 15.3 mg/g (SW2) at 295 K. Kinetic studies with different specific dosages (0.05 gCLI/mgNH4-N), temperatures (283–307 K) and pre-loaded CCP 20 (0–11.4 mg/g) were conducted. At a higher temperature a higher load was achieved. Already after 30 min contact time, regardless of the sludge water, a high load up to 7.15 mg/g at 307 K was reached, achieving equilibrium after 120 min. Pre-loaded sorbent could be further loaded with ammonium when it was recontacted with the SW. 相似文献
15.
复合型改性木质素基钻井液用降粘剂的性能研究 总被引:1,自引:0,他引:1
以马尾松硫酸盐制浆黑液为原料,经化学改性制备复合型改性木质素基钻井液用降粘剂,并对其在钻井液中的降粘性能进行实验室评价。研究结果表明,该降粘剂既能发挥无机降粘剂良好的降粘作用,又具有木质素系降粘剂良好的抗温、抗盐效果,具有较好的协同作用。加入0.5%降粘剂的淡水基浆,降粘率可达96.7%。 相似文献
16.
脱色甘氨酸母液的废活性炭,是一类吸附有有机胺类聚合物且难以再生的危险固体废弃物。本文探索性地开展了微波法再生脱色甘氨酸母液废活性炭的研究,考察了活性炭在微波炉中的放置方式、含水率以及微波反应条件等对活性炭再生率和炭损率的影响,分别采用红外光谱法、BET法对活性炭进行了分析表征。实验结果表明,在功率640 W、反应时间8 min的条件下,废活性炭的再生率达99%、综合再生率达59.0%,对再生活性碳进行红外光谱分析表明,在微波功率大于480 W后,微波辐射能有效去除废活性炭中的有机物;在微波功率800W条件下,再生活性炭的BET比表面积由废活性炭的128.15 m2/g提高到1398.5437 m2/g,已达到新鲜活性炭的性能。 相似文献
17.
综述了水和白酒中异味物质检测的样品前处理方法(包括液液萃取、固相萃取、液相微萃取、固相微萃取、搅拌棒吸附萃取、吹扫捕集、顶空等)和检测方法(包括气相色谱法、气相色谱-质谱法、气相色谱-飞行时间质谱法)的研究进展(引用文献52篇)。 相似文献
18.
白酒中甜蜜素的无衍生离子色谱法检测 总被引:5,自引:0,他引:5
建立了免化学试剂离子色谱-抑制电导检测白酒中甜蜜素的方法。选用Dionex Ionpac AS17(250 mm×4 mm)分离柱,优化了电解水在线产生KOH淋洗液的梯度淋洗程序,样品无需衍生化,稀释后过0.22μm滤膜及OnGuardⅡRP离子色谱前处理小柱后直接进样检测,外标法定量。在0.05~20.0 mg/L范围内,甜蜜素的质量浓度与色谱峰面积呈良好的线性关系(r2=0.999 2),检出限为0.072 mg/L;峰面积和峰高的相对标准偏差(n=10)分别为1.6%、2.0%;加标回收率为85%~103%。该方法简便易行、误差因素少,无干扰、选择性好、灵敏度高、分析结果准确,适用于白酒中甜蜜素的检测。 相似文献
19.
Palmer SJ Grand LM Frost RL 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(1):156-160
Raman spectroscopy has been used to characterise nine hydrotalcites prepared from aluminate and magnesium solutions (magnesium chloride and seawater). The aluminate hydrotalcites are proposed to have the following formula Mg(6)Al(2)(OH)(16)(CO(3)(2-))·xH(2)O, Mg(6)Al(2)(OH)(16)(CO(3)(2-),SO(4)(2-))·xH(2)O, and Mg(6)Al(2)(OH)(16)(SO(4)(2-))·xH(2)O. The synthesis of these hydrotalcites using seawater results in the intercalation of sulfate anions into the hydrotalcite interlayer. The spectra have been used to assess the molecular assembly of the cations and anions in the hydrotalcite structures. The spectra have been conveniently subdivided into spectral features based upon the carbonate anion, the hydroxyl units and water units. This investigation has shown the ideal conditions to form hydrotalcite from aluminate solutions is at pH 14 using a magnesium chloride solution at a volumetric ratio of 1:1. Changes in synthesis conditions resulted in the formation of impurity products aragonite, thenardite, and gypsum. 相似文献
20.
Araujo E Rodríguez-Malave AJ González AM Rojas OJ Peñaloza N Bullón J Lara MA Dmitrieva N 《Applied biochemistry and biotechnology》2002,97(2):91-103
In this work, the effect of Fento’s reagent on the degradation of residual Kraft black liquor was investigated. The effect
of Fenton’s reagent on the black liquor degradation was dependent on the concentration of H2O2. At low concentrations (5 and 15 mM) of H2O2, Fenton’s reagent caused the degradation of phenolic groups (6.8 and 44.8%, respectively), the reduction of reaction medium
pH (18.2%), and the polymerization of black liquor lignin. At a high concentration (60 mM) of H2O2, Fenton’s reagent induced an extensive degradation of lignin (95–100%) and discoloration of the black liquor. In the presence
of traces of iron, the addition of H2O2 alone induced mainly lignin fragmentation. In conclusion, Fenton’s reagent and H2O2 alone can degrade residual Kraft black liquor under acidic conditions at room temperature. 相似文献