火焰原子吸收光谱法测定铝土矿中钾、钠     

陈忠书  金绍祥 《矿产与地质》2007,21(5):599-600

采用自制封闭溶样器对铝土矿进行处理，在盐酸介质中，用火焰原子吸收光谱仪于波长598．2nm处，测定Na2O的吸光度；于波长766．7nm处，测定K2O的吸光度。此方法适合对铝土矿中钾、钠的测定，具有选择性好，操作简便、快速，测定结果准确等优点。  相似文献   

碘化钾-甲基异丁基甲酮萃取-火焰原子吸收分光光度法连续测定地球化学样品中痕量银镉铊     

肖凡  徐崇颖  邢刚  付爱瑞 《岩矿测试》2007,26(1):67-70

研究了碘化钾-甲基异丁基甲酮（KI—MIBK）萃取-火焰原子吸收分光光度法连续测定地球化学样品中痕量银、镉和铊的主要条件。通过对火焰原子吸收分光光度计气路控制系统及雾化器的改进，较大地改善了萃取-火焰原子吸收分光光度法测定银、镉和铊的稳定性和灵敏度。选择萃取酸度为1．2mol／L HCl、水相和有机相体积配比为3：1～4：1，方法精密度（RSD，n=12）为Ag4．5％～9．6％、Cd1．5％～7．9％、T14．5％～5．4％，检出限（3s）为Ag0．004μg/g、Cd0．007μg／g、T10．011μg/g，符合多目标地球化学调查样品测试及质量监控要求。用国家一级标准物质和密码组合标准物质进行验证，测试结果令人满意。  相似文献   

气球携带碘化银焰弹增雨雪效果分析     

孙立德  关心  李宝刚  高鹏  孙子媛  梁志兵  杨劲  季贺成  戴立大 《气象与环境学报》2019,35(5):93-99

利用2003—2017年观测资料,分析了喀左县采用气球携带碘化银焰弹方法人工增雨雪的效果。结果表明：天气形势为蒙古气旋、短波槽、冷涡时,取得的人工增雨雪效果较好。气球焰弹增雪播撒的高度在2000—4000 m,增雨的播撒高度在3000—5000 m,以稳定层状云中的层云、雨层云、高层云最明显。在-10℃温度条件下,冰核生成率平均为6.3×10¹³个/g;喀左县每年降水量平均为505.87 mm,比全市各县平均448.33 mm增加57.54 mm,每年增雨折合水量为1.29×10⁸ m³。气球焰弹增雨每年增加量为31.31 mm,增加降水7.007×10⁷ m³;投入产出比为1∶97.1。气球携带碘化银焰弹增雨雪方法可为其他地区相关业务提供科学参考和技术支撑。  相似文献   

Temporal trends of brominated flame retardants in coastal waters of Japan and South China: Retrospective monitoring study using archived samples from es-Bank, Ehime University, Japan     

Shinsuke Tanabe   《Marine pollution bulletin》2008,57(6-12):267

The present paper is a summary of studies conducted at the Center for Marine Environmental Studies, Ehime University, on temporal trends of brominated flame retardants (BFRs) in coastal waters of Japan and South China. Archived marine mammal fat tissues and dated sediment cores were used to evaluate temporal trends of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) in relation to their usage in the region. The results indicate that environmental concentrations of these BFRs in Japan and South China increased significantly during the last several decades. Temporal trends in the contaminant concentrations were consistent with historical consumption of the corresponding BFRs. PBDE levels in marine mammals and sediments from Japan, after showing peak concentrations in the 1990s, appear to be leveling off in recent years, in accordance with the discontinued usage of Tetra- and Octa-BDEs in Japan from the 1990s. The change in concentration levels was also accompanied by changes in PBDE congener profiles, i.e. shift towards increased proportion of higher brominated BDEs. Furthermore, in recent years HBCD concentrations in marine mammals from Japan appear to exceed those of PBDEs, presumably reflecting increasing usage of HBCDs over PBDEs. In finless porpoises from the South China Sea, PBDE levels were much higher than HBCD concentrations both in the past and recent years, implying consumption of HBCDs was not as high as that of PBDEs in China. In dated sediment cores from Tokyo Bay, concentrations increased exponentially with doubling times of 4.6–7.9 years, 6.1–12 years and 7.1–12 years for BDE-209, ΣPBDEs and HBCDs, respectively.  相似文献   

Development of an Analytical Method for the Determination of Trace Lead in Lake Water Samples by Flame Atomic Absorption Spectrophotometry after Vortex Assisted-Stearic Acid Coated Magnetic Nanoparticle Based Extraction     

Hakan Serbest 《洁净——土壤、空气、水》2023,51(2):2200229

In the present study, a method is proposed for the determination of lead at trace levels by slotted quartz tube-flame atomic absorption spectrophotometry (SQT-FAAS) after preconcentration with stearic acid coated magnetic nanoparticle-based dispersive solid phase extraction (SA-MNP-DSPE). The slotted quartz tube (SQT) is used to enhance the analyte atom residence time in the light path. Stearic acid coated magnetic iron oxide (Fe₃O₄) nanoparticles, which can be easily collected with an external magnet, are used as adsorbent in the extraction process. The limit of detection (LOD) and the limit of quantitation (LOQ) values of the proposed method are obtained as 0.90 and 2.9 µg L⁻¹, respectively. The method allows high repeatability in a wide linear range between 5.0 and 250 µg L⁻¹, and the relative standard deviation for six replicates is 5.8%. The detection power is enhanced by about 77-fold compared to the regular flame atomic absorption spectrophotometry (FAAS) system. The method is validated by recovery experiments to four different lake water samples. After the spiking tests, good recovery results are calculated between 97% and 106%. These results show that lead can be detected at low levels in lake water samples with high sensitivity, accuracy, and precision.  相似文献   

Isomer specific determination of hexabromocyclododecanes (HBCDs) in small cetaceans from the South China Sea--Levels and temporal variation   总被引：1，自引：0，他引：1  

Isobe T  Ramu K  Kajiwara N  Takahashi S  Lam PK  Jefferson TA  Zhou K  Tanabe S 《Marine pollution bulletin》2007,54(8):1139-1145

A diastereoisomer (alpha, beta, and gamma) specific analytical method for measuring hexabromocyclododecanes (HBCDs) was developed using liquid chromatography-tandem mass spectrometry (LC-MS-MS). The method developed was applied to analyze blubber of small cetaceans to divulge the distribution and temporal variation of HBCDs in the Asian marine environment. HBCDs were detected in all the blubber samples of finless porpoises (Neophocaena phocaenoides) and Indo-Pacific humpback dolphins (Sousa chinensis) collected from the South China Sea during 1990-2001. Concentrations of HBCDs were higher in humpback dolphins (31-380 ng/g lipid) than in finless porpoises (4.7-55 ng/g lipid), which can be attributed to habitat differences. Average concentrations of alpha-HBCD in finless porpoises increased from 9.5 ng/g lipid in 1990 to 35 ng/g lipid in 2000/01. alpha-HBCD was predominant among the three isomers with some exceptions in finless porpoises collected in 1990. This is the first report on HBCDs contamination in marine mammals from Southeast Asia.  相似文献   

火焰原子吸收光谱法快速测定铁矿石中铅锌铜   总被引：6，自引：3，他引：3  

余清  陈贺海  张爱珍  王宝钢 《岩矿测试》2009,28(6):598-599

将ISO、国家标准等方法中同一铁矿石样品分别称样,用不同的方法溶样,再分别测定改进为对同一样品一次称样,盐酸、氢氟酸一次性溶样,应用空气-乙炔火焰原子吸收光谱法连续测定同一进口铁矿石中铅、锌和铜含量,可简化操作,减少误差。方法准确、可靠,提高了工作效率和经济效益。  相似文献   

三乙醇胺增敏火焰原子吸收光谱法测定地质样品中的钼   总被引：2，自引：1，他引：1  

黄仁忠 《岩矿测试》2009,28(6):587-589

样品经王水分解,加入适量的三乙醇胺增敏,用空气-乙炔火焰原子吸收光谱法测定地质样品中的钼。选择了三乙醇胺的最佳用量;比较了钼在盐酸-磷酸-铝盐、盐酸-三乙醇胺、盐酸-三乙醇胺-磷酸、盐酸-三乙醇胺-磷酸-铝盐等4种不同介质中的特征浓度。结果表明,在盐酸-三乙醇胺-磷酸-铝盐介质中,钼的质量浓度≤40 mg/L内线性良好,方法检出限为0.2 mg/L,相对标准偏差为5.2%(n=6),加标回收率为96%~102%。对国家一级标准物质进行测定,结果与标准值相符。  相似文献   

Identification of the natural product 2,3,4,5-tetrabromo-1-methylpyrrole in Pacific biota, passive samplers and seagrass from Queensland, Australia     

Gaul S  Bendig P  Olbrich D  Rosenfelder N  Ruff P  Gaus C  Mueller JF  Vetter W 《Marine pollution bulletin》2011,62(11):2463-2468

Halogenated natural products (HNPs) are frequently detected in marine organisms. High HNP concentrations have previously been found in marine mammals from the Great Barrier Reef, Australia, including in the blubber of herbivorous dugongs (Dugong dugon). To identify the source of HNPs we initially focused on the analysis of Australian seagrass (Halophila ovalis) which serves as the principal food source for dugongs. GC/MS analysis of the seagrass indicated the presence of several organobromine compounds. One compound was identified as 2,3,4,5-tetrabromo-1-methylpyrrole (TBMP) by synthesis. Subsequent analysis of semipermeable membrane devices demonstrated that the photo-sensitive TBMP is widespread in the Great Barrier Reef (Queensland, Australia). The detection of larger TBMP concentrations in fish fillets from Chile and traces in mussels from New Zealand indicated that this potential HNP may be distributed throughout the Southern Pacific Ocean.  相似文献   

富氧空气/甲烷对向流扩散火焰的实验研究     

冯耀勋  赵黛青  贾明生  郑晓峰 《广东海洋大学学报》2006,26(4):71-75

为了开发实际适用的富氧燃烧技术,本研究对对向流扩散火焰这一典型的扩散燃烧形态为对象进行实验考查,发现得到的实验结果与作者先前进行的数值模拟结果得到比较好的吻合,即利用详细的基元反应动力学模型对火焰的数值模拟可以很好的再现火焰特性;在此基础上利用CCD成像技术进一步研究了燃料稀释浓度、氧化剂浓度的变化对富氧空气/甲烷对向流扩散火焰形态的影响规律。  相似文献