两种测定水溶肥中全磷方法的比较研究

通过实验比较磷钼酸喹啉重量法和磷钒钼黄比色法对8个不同类型水溶肥料样品磷含量的测定过程、测定结果及准确性等。结果表明:两种测定方法所测得的结果均符合质控要求,且相关性高,相关系数为0.999。相比较而言,比色法具有准确性高、操作简单、耗时短等优点,可以作为企业内部的快速检测方法。     

8个烟碱类杀虫剂生物活性比较研究

比较吡虫啉、啶虫脒、烯啶虫胺、噻虫啉、噻虫嗪、噻虫胺、氯噻啉、呋虫胺等8个烟碱类杀虫剂的生物活性,为科学应用提供参考。采用浸渍法、浸稻苗法、浸叶碟法等对豆蚜、褐飞虱、二化螟、小菜蛾进行室内毒力测定,对活性进行分组,并进行了结构与活性关系初步分析。结果表明:烟碱类药剂对豆蚜LC50值为0.0314⁰.3505 mg/L,对抗吡虫啉的褐飞虱LC50值为0.565 70.3505 mg/L,对抗吡虫啉的褐飞虱LC50值为0.565 7⁴9.404 6 mg/L,对二化螟LC50值为7.517649.404 6 mg/L,对二化螟LC50值为7.5176¹39.0369 mg/L,对小菜蛾LC50值为10.533 4139.0369 mg/L,对小菜蛾LC50值为10.533 4¹00 mg/L。烟碱基闭环与开环、取代杂环等结构特点对药剂活性有影响。烟碱类药剂对同翅目害虫的活性显著优于对鳞翅目害虫的活性。在实际应用中可以采取轮用策略和兼治策略推进药剂的科学合理使用,还可加强研发种子处理剂等。     

不同植物对五氯酚生物富集能力的研究

在添加2 000μg/kg五氯酚的土壤中种植芦苇(Phragmites communis(L.)Trin)、香蒲(Typh orientalis Presl)和水葱(Scirpus tabemaemontani Gmel),探讨不司植物对土壤中五氯酚的富集作用.植物和土壤样品以石油醚振荡提取90min,浓硫酸净化和碳酸...     

高效液相色谱法测定化妆品中8种有毒有害物质

文章建立了高效液相色谱(HPLC)法同时测定化妆品中尼泊金甲酯、尼泊金乙酯、尼泊金丙酯、尼泊金丁酯和三氯生、氯霉素、甲基睾丸酮、己烯雌酚的检测方法。该方法采用C18色谱柱,以乙腈-水为流动相,用梯度洗脱方式,实现了对8种物质的良好分离。结果表明:8种物质的线性相关系数r0.9992,回收率为93.8%～114.0%,方法相对标准偏差RSD1%。     

兼具脱氮和除磷性能菌株的优选

通过L9（34）正交试验和单因素实验优化培养条件,从七株不同菌属的异养硝化-好氧反硝化菌中优选兼具除磷性能菌株。结果表明：优选出的两株异养硝化-好氧反硝化菌分别为丛毛单胞菌WXZ-17和芽孢杆菌WXZ2-4,二者均具有厌氧除磷性能,磷化氢为重要除磷产物。优选的两株菌培养条件均为： T=32.0℃、 pH=6.50、氮源为蛋白胨＋氯化铵＋硝酸钠、总磷浓度为20.0 mg/L,相应的除磷率分别为25.6％和36.0％。在早期脱氮实验中已证实该两株菌脱氮效率分别为：89.7％和96.4％。筛选出的兼具脱氮和除磷性能的菌株使实现废水同步脱氮除磷成为可能。     

聚乙烯醇海绵产品与几种临床用抗生素对致病菌抑菌能力的比较研究实验

本公司负压封闭引流套装中的泡沫为聚乙烯醇缩甲醛泡沫,是一种生物活性材料,对大肠杆菌、金黄色葡萄球菌、绿脓杆菌有抑制作用。大肠杆菌、金黄色葡萄球菌、绿脓杆菌是引起感染的主要病菌,临床上经常使用利凡诺、庆大霉素、呋喃西林对这三种致病菌进行抑制作用。所以本实验探讨了利凡诺、庆大霉素、呋喃西林和聚乙烯醇缩甲醛泡沫对大肠杆菌、金黄色葡萄球菌、绿脓杆菌三种致病菌的抑菌能力,并作比较,验证聚乙烯醇缩甲醛泡沫的生物抑菌性。     

Effect of Heavy Metals in Plants of the Genus Brassica

Several species from the Brassica genus are very important agricultural crops in different parts of the world and are also known to be heavy metal accumulators. There have been a large number of studies regarding the tolerance, uptake and defense mechanism in several of these species, notably Brassica juncea and B. napus, against the stress induced by heavy metals. Numerous studies have also been published about the capacity of these species to be used for phytoremediation purposes but with mixed results. This review will focus on the latest developments in the study of the uptake capacity, oxidative damage and biochemical and physiological tolerance and defense mechanisms to heavy metal toxicity on six economically important species: B. juncea, B. napus, B. oleracea, B. carinata, B. rapa and B. nigra.     

两种覆盖材料阻隔湖泊污染底泥磷释放的研究

本研究建立了一套模拟湖泊小试装置,分别采用含粘土的沙子和清洁黄土两种材料覆盖污染底泥阻隔磷释放。实验控制在恒温25℃厌氧条件下进行。经过60d静置和15d扰动实验,结果表明,沙子和黄土覆盖厚度达到5cm以上,均能有效抑制底泥P释放,且覆盖厚度越厚,抑制P释放的效果越好。因此,从工程成本和取材方便的角度考虑,采用5cm~15cm厚度即可。扰动会加速促进底泥P释放,采用覆盖法控制内源磷污染时,要尽量减少对覆盖材料的扰动。     

Kinetic Study of the Scavenging Reaction of the Aroxyl Radical by Eight Kinds of Vegetable Oils in Solution

A detailed kinetic study was performed for the reaction of the aroxyl radical (ArO?) with eight vegetable oils 1–8, which contain different concentrations of α‐, β‐, γ‐, and δ‐tocopherols and ‐tocotrienols (‐Tocs and ‐Toc‐3s). The second‐order rate constants (k_s) and aroxyl radical absorption capacity (ARAC) values for the reaction of ArO? with vegetable oils 1–8 (rice bran 1, perilla 2, rapeseed 3, safflower 4, grape seed 5, sesame 6, extra virgin olive 7, and olive oils 8) were measured in ethanol/chloroform/D₂O (50:50:1, v/v/v) solution at 25 °C using stopped‐flow spectrophotometry. The k_s value (16.1 × 10^?3 L g^?1 s^?1) of rice bran oil 1 with the highest activity was 8.0 times larger than that (2.02 × 10^?3) of olive oil 8 with the lowest activity. The concentrations (in mg 100 g^?1) of α‐, β‐, γ‐, and δ‐Tocs and ‐Toc‐3s contained in the vegetable oils 1–8 were determined using high performance liquid chromatography‐mass spectrometry/mass spectrometry (HPLC‐MS/MS). From these results, it was clarified that the ArO?‐scavenging rates (k_s) (i.e., the relative ARAC value) obtained for the vegetable oils 1–8 may be well explained as the sum of the product of the rate constant () and the concentration ([AOH‐i]/10⁵) of AOH‐i (Tocs and Toc‐3s) included in vegetable oils. The results suggest that the ARAC assay method might be used in the evaluation of antioxidant activity of general food extracts.     

四种魔芋中神经酰胺含量比较研究

利用HPLC-ELSD法测定了4种魔芋中的神经酰胺含量。结果表明,4种魔芋中的神经酰胺含量呈现种间差异。其中神经酰胺含量最高的是M4,为43．75μg·g^-1。     

同时测定工作场所空气中8种有毒物质

将分析条件相近的工作场所空气中8种有毒物质(丙酮、乙酸乙酯、丁酮、三氯乙烯、四氯乙烯、乙酸丁酯、苯乙烯、环己酮),采取二硫化碳解吸,用气相色谱仪,配氢火焰检测器、FFAP不锈钢填充柱,利用实验摸索出的色谱条件,一次进样,同时分析。比标准规定的单一分析法大大提高了检测分析效率,满足了用户要求快速出分析结果的需要。通过配置混合标样,建立各物质的标准曲线,用标准样进行精密度测试,准确度测试,精密度为:相对标准偏差(1.17%～2.30%),准确度为:(相对误差0.72%～2.91%),完全符合各个物质检测标准中要求的技术指标。