Dynamic Effect of Operational Regulation on the Mesophilic BioMethanation of Grape Marc

Wine production annually generates an estimated 11 million metric tonnes of grape marc (GM) worldwide. The diversion of this organic waste away from landfill and towards its use in the generation of renewable energy has been investigated. This study aimed to evaluate the effectiveness of operational parameters relating to the treatment regime and inoculum source in the extraction of methane from GM under unmixed anaerobic conditions at 35 °C. The study entailed the recirculation of a previously acclimated sludge (120 days) as downstream inoculum, an increased loading volume (1.3 kg) and a low substrate-to-inoculum ratio (10:3 SIR). The results showed that an incorporation of accessible operational controls can effectively enhance cumulative methane yield (0.145 m³ CH₄ kg⁻¹ VS), corresponding to higher amounts of digestible organics converted. The calculated average volumetric methane productivity equalled 0.8802 L CH₄ L_Work⁻¹ d⁻¹ over 33.6 days whilst moderate pollutant removal (43.50% COD removal efficiency) was achieved. Molecular analyses identified Firmicutes and Bacteroidetes phyla as core organisms for hydrolytic and fermentative stages in trophic relationships with terminal electron acceptors from the methane-producing Methanosarcina genus. Economic projections established that the cost-effective operational enhancements were sustainable for valorisation from grape marc by existing wineries and distilleries.     

微波消解/ICP-MS法检测蒙脱石散中五种金属元素残留的方法学研究

药物中金属的残留危害着人类的身体健康,因此对药物中的残留金属含量进行检测已成为一项重要的检测项目。本文基于《中华人民共和国药典》(2015年版)方法,测定蒙脱石散中的5 种金属元素（As、Cd、Cu、Pb 和 Mg）,优化了微波消解仪和四极杆电感耦合等离子体质谱仪的最佳工作参数。通过优化测定方法,检出限为As 0.05 μg/L、Cd 0.1 μg/L、Cu和Pb 1 μg/L、Mg 100 μg/L;方法定量限为As 0.02 μg/g、Cd 0.03 μg/g、Cu和Pb 0.33μg/g、Mg 33.33 μg/g;重复性和稳定性的RSD均小于5%;加标回收率为As和Cd 70%~125%、 Cu 75%~120%、Mg 92%~105%、Pb 80%~115%。使用上述方法对国内外8个批次不同品牌的蒙脱石散进行方法验证,评估结果表明,该方法操作简单,结果准确可靠,适用于蒙脱石散样品中As、Cd、Cu、Pb和Mg的测定,可为蒙脱石散的质量评价和服用安全性提供理论依据和技术支持。     

微波消解ICP-AES法测定ABS中Pb、Cd、Hg

以ABS塑料为研究对象,采用微波消解法进行样品的前处理,使用电感耦合等离子体发射光谱法测定ABS塑料中Pb、Cd、Hg,结果表明,Pb、Cd、Hg加标回收率均在95~105%之间,测试精密度均小于3%,该方法在缩短样品前处理时间的同时得到较高的元素消解回收率和较为理想的精确度,适用于ABS塑料中重金属含量的快速测定。     

Changes in Antioxidant Properties and Amounts of Bioactive Compounds during Simulated In Vitro Digestion of Wheat Bread Enriched with Plant Extracts

Cereal preparation can be an excellent source of substances with proven health-promoting properties. Unfortunately, some types of bread, such as white flour bread, are devoid of many valuable nutrients. Therefore, it is necessary to look for ways to increase its density and nutritional value. The aim of the study was to investigate the effect of stabilized plant extracts on the quality of bread, its antioxidant activity and polyphenol content, and to evaluate the stability of bioactive compounds and antioxidant activity during in vitro digestion. The research material was the wheat bread baked with spray dried microcapsules of hawthorn bark, soybeans and onion husks in maltodextrin or inulin carriers. The addition of plant extracts resulted in the presence of phenolic compounds in the wheat bread, and its antioxidant activity significantly increased. There was no significant difference in antioxidant activity between breads containing microcapsules with different carriers. During in vitro digestion, procyanidins and isoflavones in bread were more resistant to the digestive processes than other compounds. The antioxidant activity during simulated digestion was the highest at the stage of gastric digestion, and its value depended on the extract used and the analytical method applied.     

四种藏药成方制剂中铅、砷含量的湿法消化-流动注射氢化物发生-原子吸收光谱法测定研究

选择藏族地区常用的四种藏药成方制剂安置精华散、当佐、仁青常觉和七十味珍珠丸作为研究对象,通过优化消化条件和测定条件,探索建立其铅、砷含量测定的湿法消化与流动注射氢化物发生-原子吸收光谱(FI-HAAS)联用分析方法,并对其铅砷含量进行精确测定。在优化的工作条件下,铅和砷的检出限分别为：0.067和0.012 μg·mL-1;定量限分别为：0.22和0.041 μg·mL-1;线性范围分别为：25～1 600 ng·mL-1(r=0.999 5),12.5～800 ng·mL-1(r=0.999 4);精密度(RSD)分别为：2.0%和3.2%;加标回收率范围分别为：98.00%～99.98%和96.67%～99.87%。四种藏药成方制剂的铅、砷含量测定结果如下,安置精华散中铅砷含量分别为：0.63～0.67和0.32～0.33 μg·g-1;当佐为：42.92～43.36和24.67～25.87 μg·g-1;仁青常觉为：1 611.39～1 631.36和926.76～956.52 μg·g-1;七十味珍珠丸为：1 102.28～1 119.27和509.96～516.87 μg·g-1。本研究建立了藏药成方制剂中铅、砷检测方法,并测定了四种藏药成方制剂中铅、砷含量,为其在临床安全有效使用提供了参考依据。     

微波消解植物灰分与环境土壤中微量元素的ICP-AES方法研究

应用MDS-2002A犁压力自控密闭微波消解样品制备系统,针对研究样品的特性和共性,进行植物灰分和土壤样品相同微波消解条件的研究实验,并采用电感耦合等离子体原子发射光谱法测定其元素的含量.讨论了混合酸体系、混酸配比、固液比和微波消解时间对于样品制备结果的影响.最终的优选方案为A281C2,即微波程序为工步2,混酸配比为6:2:1:1,混合酸体系为HNO3-HCl-HF-HClO4,最高功率消解时间为10 min的条件下,消解结果最佳.在微波消解最佳条件下,进行了方法准确度实验和测量结果重现性实验,该方法经土壤(GBW07401)和植物(GBW07603)国家标准物质验证,所得测试结果的相对误差均在0.00%～7.14%之间,相对标准偏差均在0.87%～5.25%之间.结果表明,微波消解法处理植物灰分和土壤样品,具有快速、简便、节省试剂、消解完全等特点,测定结果的准确度和精密度令人满意.     

对-叔丁基杯[8]芳烃键合硅胶制备及其毛细管电色谱性能研究

以γ-(环氧丙氧)丙基键合硅胶为前体,于硅胶表面键合环氧基,在催化剂存在下以杯芳烃钠盐开环制备杯芳烃键合硅胶固定相.该方法反应条件温和,适用性强.将这个新方法首次用于制备对-叔丁基杯[8]芳烃电色谱键合固定相(C8BS),采用加压电色谱初步评价其电色谱性能.研究结果表明,C8BS电渗流(Electrosmoticflow,EOF)较小,但通过控制键合反应及使用压力辅助电色谱可部分弥补上述不足.该固定相的EOF受流动相pH影响小(pH=3-8),同时大环配体屏蔽效应能有效地克服硅羟基引起的碱性化合物拖尾现象,这对电色谱分离具有重要意义.通过分步封尾研究EOF的来源发现,杯芳烃酚羟基对EOF有弱的贡献,这与报道的杯芳烃涂层具有径向电渗流调控能力相一致.     

悬浮液进样流动注射在线微波消解-冷蒸气原子荧光光谱法测定生物和环境样品中的汞

建立了悬浮液进样流动注射在线微波消解-冷蒸气原子荧光光谱法测定生物和环境样品中Hg的方法。样品分散在50％(V/V)王水中,通过磁力搅拌保证样品溶液的均一性与稳定性。方法的检出限为O．06μ/L。方法简单快速,灵敏度高,样品损失少,而且没有样品交叉污染。应用此方法测定了5种标准参考物质以及5个实际样品中的Hg含量,并与传统的高压焖罐强酸消解方法进行了比较,两种方法所得结果一致,标准参考物质的测定值与标准值很好地吻合。     

螺旋藻中铅镉的ICP-MS测定

采用微波消解、高压罐消化以及HNO3 HClO4消化3种方法对螺旋藻样品进行处理,比较了不同方法产生的空白值和加标回收率。建立了微波消解-电感耦合等离子体质谱法测定螺旋藻样品中的铅镉的方法。铅镉检出限分别为0.06ng mL和0.05ng mL,RSD均小于3%,加标回收率在98%～101%之间。方法用于实际样品分析。     

微波消解和氢化物发生ICP-AES法测定煤中痕量砷

建立了硝酸 盐酸 氢氟酸微波消解样品,氢化物发生ICP AES法测定煤中痕量砷的方法。考察了微波消解、酸性介质和硼氢化钠浓度的最佳条件。在选定的操作条件下,砷的检出限为0.3μg·L-1,相对标准偏差(n=5)小于4%。方法准确、快速,用本法测定国家标准参考物质的结果与推荐值一致。