Sediment records of Sb and Pb stable isotopic ratios in Lake Qinghai

A sediment core in Lake Qinghai in northwest China was collected in 2006. ¹³⁷Cs and ²¹⁰Pb activities were analyzed to investigate the chronology of the sediment core. Sb and Pb concentrations, and Pb stable isotopic ratios were analyzed to study the historical atmospheric deposition records and sources of Sb over the past 15 centuries. The Sb concentration was 4.21 ± 1.52 μg/g in the sediments, its vertical distribution of Sb shows three large peaks in the recent two centuries, 1799, 1896 and 1944, coincided with Sb contamination from large wars, respectively. The peak in 1920 responded the large earthquake that happened in northern China, which was not far away from Lake Qinghai. The Sb/Pb ratio, ²⁰⁶Pb/²⁰⁷Pb and ²⁰⁸Pb/²⁰⁶Pb results suggest that Sb and Pb were probably from the ores in South China and coals in North China before 1965, but obviously from uses of leaded gasoline after 1965.     

青海省宗教场所旅游资源的空间格局及影响因素研究

青海省宗教发展历史悠久,宗教旅游资源丰富,宗教场所的空间分布特征对青海省区域旅游格局有重要影响.对青海省宗教场所旅游资源进行了统计,分别从空间分布模式、差异性、密度等方面采用最邻近指数、地理集中指数、洛伦茨曲线、核密度方法对其空间格局特征进行了定量分析,并利用空间回归分析法探讨了其分布与海拔、坡度、交通、水系等因素的关系.结果表明：青海省宗教场所旅游资源呈"东多西少"的集聚分布态势,空间差异显著,旅游资源集中在青海省11%地区;空间分布密度呈由东向西辐射（型）的分布趋势;空间回归分析结果显示,在地势平坦、水资源丰富、交通便捷的地区宗教场所旅游资源较丰富.     

Mössbauer Spectroscopic Study on Vertical Distribution of Iron Species in Sediments from Qinghai Lake,China

In this study, ⁵⁷Fe Mössbauer spectroscopy has been applied to sediments collected from Qinghai Lake in Qinghai Province, China, to investigate the vertical distribution of iron species. Their Mössbauer spectra consisted of four doublets ascribable to one paramagnetic high-spin Fe³⁺, two paramagnetic high-spin Fe²⁺ with different quadrupole splittings, and one diamagnetic low-spin Fe²⁺ that corresponds to pyrite (FeS₂). The distribution of pyrite suggested climatic changes during the past nine thousand years. It was demonstrated that the iron speciation in the salt lake sediments by Mössbauer spectroscopy can be used to reconstruct the past environment.

     

种植青海大黄中微量元素研究

青海地道中药材“西宁大黄”野生资源濒临枯竭,人工种植规模不断扩大。定期采集青海西宁及邻近地区两年生种植大黄,跟踪分析了其微量无素铜、锌、铁、锰、铬,为地道西宁大黄资源的可持续开发和利用提供科学依据。研究表明,种植大黄中微量元素铁、锌、铜、锰的有效积累以及土壤地球化学环境中的微量元素锌、锰、铜对种植大黄的生长具有重要的作用和意义。     

地基CE312热红外辐射计定标方法分析与评价

地基CE312热红外辐射计用于星载传感器的定标,其定标精度直接影响热红外传感器的场地定标精度。文章论述CE312-1b带宽辐亮度定标法和分谱辐亮度定标法的定标原理,利用实验室黑体对CE312-1b热红外辐射计进行定标,最后利用2010年8月青海湖的野外实测数据结合MODIS观测值,分析对比两种定标方法所得定标结果的准确性及误差来源。结果表明,带宽辐亮度定标法得到的CE312热红外辐射计定标系数相对分谱辐亮度定标法所得结果在准确性、适用性方面表现更好。     

种植青海大黄叶中矿物质元素研究

青海地道中药材“西宁大黄”，野生资源濒临枯竭，人工种植规模不断扩大。定期采集了青海西宁及邻近地区两年生种植大黄叶，分析测试了其矿物质元素，为西宁大黄资源的可持续开发和利用提供科学依据。研究表明，种植大黄叶中矿物质营养元素的协同性以及有效蓄积对大黄的生长具有重要意义。钠元素在大黄叶中的有效蓄积以及环境中水分的及时补给对种植大黄的生长具有重要作用。     

青海省唐古特铁线莲中齐墩果酸含量的测定

建立了唐古特铁线莲中齐墩果酸含量测定的HPLC方法。色谱条件:采用Phenomenex Luna C18(250 mm×4.6 mm,5μm),流动相:乙腈-0.2%H3PO4(35:65),流速:1 mL/min,柱温:室温(25℃),检测波长:205 nm。齐墩果酸在0.0233～0.7000 mg范围内呈良好的线性关系,线性回归方程为y=2E+06x+360803,R2=0.9917,回收率RSD为1.7%,并对青海省野生和栽培唐古特铁线莲中齐墩果酸进行了定量分析,结果显示前者平均值为0.1184%,后者平均值为0.0651%。方法可用以测定唐古特铁线莲中齐墩果酸的含量。     

微波密闭消解ICP-AES法测定土-草-畜系统中无机元素

采用微波密闭消解电感耦合等离子发射光谱法(ICP-AES)对青藏高原土壤-牧草-家畜矿物质系统中无机元素K,Ca,Na,Mg,P,S,Fe,Cu,Mn,Mo,Co和Zn的含量进行了测定,对土壤样品消解采用HNO3-HF-H2O2酸溶体系,而草畜样品消解则采用HNO3-H2O2酸溶体系,以简化实验操作,降低空白值。方法的相对标准偏差均在5%以下,回收率93.5%~113.5%。实验表明该方法具有良好的准确度和精密度,验证了分析数据的可靠性,为研究青藏高原土-草-畜矿物质系统中矿物质元素含量、循环、互作以及在放牧补饲生产中科学运用矿物质元素与添加剂提供了科学依据。     

Origin of Ketones in Sediments of Qinghai Lake

This paper analysed the ketone fractions in sediments and living organisms of Qinghai Lake using GC-MS and discussed their origin,n-Alkan-2-ones detected in the sediments ranged from C_(12) to C_(33) with a maximum at n-C_(25) or n-C_(29) and showed a strong odd predominance, n-Alkan-2-ones in the living organisms analysed ranged from C_(15) to C_(31) with a maximum at n-C_(27).The authors believed that ketones in modern sediments may directly derive from biosynthesis.     

青海省西宁种植山莨菪中重金属元素特征

青海地道中藏药材山莨菪人工引种栽培试验成功。采集两年生和三年生种植山莨菪在不同生长期的植物全植株,采用流动注射氢化法原子吸收光谱分别测试了其不同组织中铅、砷、汞、镉等重金属元素含量。结果表明,山莨菪在生长周期内吸收的重金属元素并非全部蓄积在根组织器官中,部分重金属元素通过年生长周期内的生长发育而随着地上茎叶部分等组织器官的枯萎被代谢排出植物体外。