离子色谱法测定温泉水中多种阴阳离子

在用离子色谱法测定温泉水样中F~-、Cl~-、Br~-、NO_2~-、NO_3~-、SO_4~(2-)、PO_4~(2-)等阴离子和Li~+、Na~+、K~+、Mg~(2+)、Ca~(2+)等阳离子过程中,研究了用油泵超声波池内脱气法处理H_2CO_3过饱和水样以排除HCO_3~-对阴离子检测干扰的方法.研究采用青岛普仁仪器有限公司生产的PIC-8型离子色谱仪,分离柱为TSK-GEL SuperIC-CationColumn(150 mm×4.5 mm)离子分离柱,以1.9 mmol/L碳酸钠-1.8mmol/L碳酸氢钠作为阴离子淋洗液,流量为1.5 Ml/min;以2 mmol/L HNO_3为阳离子淋洗液,流量为1.0 ml/min,测定了腾冲火山区叠水河、大滚锅两个温泉水中的阴阳离子的含量.研究结果表明:该方法简便、快速、准确可靠,可在火山和地震监测中推广使用.     

淡水可溶性硅的4种测定方法比较

通过加标回收和野外水样测定,对用于淡水可溶性硅测定的4种比色法进行比较,同时研究了实验过程中玻璃容器对4种方法测定结果的影响以及磷酸根离子对显色的干扰.结果表明:1,2,4氨基萘酚磺酸还原硅钼蓝法的灵敏度和准确性高,适合常规水样中可溶性硅的测定,最适检测浓度范围为0.05~20 mg/L;米吐尔还原硅钼蓝法和抗坏血酸还原硅钼蓝法灵敏度高但准确性低;硅钼黄法操作简单但灵敏度低.测定过程所使用的玻璃容器对4种方法的测定结果没有影响,磷酸根离子的干扰能被消除.     

地震灰色模型的建立及讨论

本文应用灰色预测的理论方法建立了云南、四川强震发震时间的灰色预测模型,表明对于Ms≥6.5地震,两省统一组成大区域灰模型,其预测值与观测值拟合很好;对于Ms≥6.0的地震,则分省建立灰色预测模型比大区域的模型精度更高,这说明不同强度地震受不同尺度范围的控制因素作用。对比几个灰模型,得到Ms≥6.5地震的模型比两个Ms≥6.0地震模型拟合精度都高,表明后者所用的原始数据比前者受到更多的噪音污染,这可能是由于后者震级参数测定精度低于前者等原因造成的。 文章用布朗滤波方法和水平图型滤波方法对所用资料是否存在偏值做了检验,证明本文中使用的数据不论从时间分市上还是从震级分布上都符合预测理论的要求。     

【已撤稿】淡水磷监测中钼酸铵分光光度法的改进

我国现行淡水水体中磷测定方法为钼酸铵分光光度法（GB 118931989）,该方法检测下限为0.01 mg/L,但我国南亚热带地区部分水体的总磷以及多数水体的溶解态磷浓度均低于0.01 mg/L,通过对标准试样和野外水样的测定,分析该方法在监测低磷浓度水体中可能出现的问题并提出改进方法.结果表明：对于磷浓度低于0.01 mg/L的水体,国标法灵敏度低,准确性差.通过3个方面的改进可提高该方法测定的灵敏度和准确性：1）将消解水样体积由25 ml增加到50 ml,消解后不再进行二次稀释定容;2）改变显色剂的配制,显色剂由14%硫酸溶液50 ml、酒石酸锑钾溶液5 ml、4%钼酸铵溶液15 ml和0.1 mol/L的抗坏血酸溶液30 ml混合而成,现配现用;3）将测定波长设置为880 nm.改进后方法的灵敏度有较大提高,能准确、有效地检测磷浓度在0.003~0.01 mg/L的水样.     

大地震震级测定及速报

为了研究在强烈地震发生时,记录图最大振幅出格,如何决速测定强震震级这一实用化很强的问题,在用面波持续时间及测定体波震级方法的基础上。本文用云南1988年11月发生在澜沧、耿马地区的两次M_S≥7.0的地震资料(由全国基准台网SK仪器记录的地震图),进一步研究用这两种方法快速测定大地震震级作为速报方法的可能性。研究结果表明,用归算的面波持续时间测定M_S作为大震速报,一般需要等待从地震图初至后延10—20分钟的时间,而用体波测定震级m_B作为大震速报仅需要等待从初至后延数秒至5分钟左右。因此,是最为实用的大震速报方法。其优点在于图上最先到达的总是体波,对于M_S≥7.0的地震,体波振幅往往不限幅,这种特征满足强震测定和大震速报的需要。本文用澜沧、耿马两次大震的资料,对这两种方法作了较好的比较和检验。用收集到的约1500多个中强地震的面波震级和体波震级数据,经验统计给出两者之间的线性关系为M_S=1.55mg-3.47。     

气氡观测中的恒流鼓泡式脱气-集气装置研制与应用

利用20 cm不锈钢高压锅作为集气室,在锅的两边上、下分别打一个进出水孔,用15 mm不锈钢管道件连接,把进水口制作成高于锅内液面,出水口与锅内液面为同一水平面,形成一高一低,一小一大两个相对稳定的动态水平液面,在进水管中引入气泵输出气体,使集气室内进水同时进行自动连续鼓泡,把水中气体脱出,在输气管中接入玻璃转子流量计控制气体流量,进行恒流鼓泡。并应用于小流量冷水井气氡观测,效果显著。     

深井水中硫酸根测定方法的改进

测定地下水中硫酸根,过去我们一直采用EDTA容量法。这一方法不仅测试周期过长,尤其对含较多微量金属元素的深井水,干扰尚难于排除,并且在结果计算上,又必须扣除水样中原有的钙镁总量,所以,往往给测定结果带来过大的误差。为此,我们对这一方法进行了改进试验,探索出一种简单、快速、准确的新方法。现介绍如下: 一、方法原理水样用阳离子交换树脂处理以除去阳离子,加入定量的钡镁混合液,硫酸根在丙酮介质中以BaSO_4形式完全沉淀,而过量的钡离子在pH=10时,当有镁离子存在下,用乙二铵四     

扩散瓶水样深及孔径对水氡测值的影响

本文叙述经过两项实验得到如下结果。 (1) 地下水氡含量测值和扩散瓶水样深线性相关,其订正公式为:ΔRn=0.044H—4.643; (2) 水氡测值受扩散瓶鼓泡孔孔径大小影响,呈非线性变化。对于“四定”水样测定中,脱气效率的高低直接影响着地下水氡含量测值的大小。具有同—V气/V水比值的100ml扩散瓶,因水样深浅或孔径大小不同,脱气效率是不一样的。实验表明,从目前各水氡测点正在使用的扩散瓶抽样对比试验结果看:氡测值随着水样深度的增加而提高,随着孔径的加大而降低,其相对误差分别高达21.76％和12.65％,都远远超过国家地震局规定的“平行样的测定,相对误差不大于5％的要求”。     

顶空气相色谱法测定水中挥发性有机污染物

介绍静态顶空气相色谱分析的原理,研究温度、相比、分配常数和无机盐等参数对顶空分析灵敏度的影响.此方法对8个挥发性苯系物的线性相关系数0.999,相对标准偏差0.95%,方法检出限1μg/L.在炼油厂废水中,检出104个色谱峰,其中苯、甲苯、乙苯、间,对二甲苯和邻二甲苯均有检出,浓度范围在268-1622μg/L.污水处理厂出口水样和废水库样品中挥发性有机物均未检出.采集15个安徽巢湖水样,挥发性苯系物和挥发性有机物均未检出(1μg/L).     

福建台网速度震级与仿真震级差异分析

选用福建地震台网“十五”观测系统运行以来记录的ML≥1．0地震资料,对测定的速度震级和仿真震级进行了震级偏差统计分析,初步得出两种震级偏差值及相关系数,并分析了震级差异形成原因,为福建地震台网震级的测定提供参考。     

A Monte Carlo study of rainfall forecasting with a stochastic model

A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities.     

Earthquake Engineering and Engineering Vibration Aims And Scope

正This journal is established by the Institute of Engineering Mechanics(IEM),China Earthquake Administration,to promote scientific exchange between Chinese and foreign scientists and engineers so as to improve the theory and practice of earthquake hazards mitigation,preparedness,and recovery.To accomplish this purpose,the journal aims to attract a balanced number of papers between Chinese and     

Foreword

Destructive earthquakes have caused great damage in China and the United States and collapsing buildings havecaused many deaths and injuries. The field of earthquake engineering studies earthquake hazards, the occurrence ofearthquakes of various magnitudes, the nature of the ground shaking during an earthquake, the vibration of structuresduring earthquakes, the strengthening of existing structures and the design of new structures to be earthquake resistant,and finally, how to cope with earthquake damage and restore a city to normal functioning. Such efforts are in progressin both countries, but unfortunately, the language barrier interferes with the free flow of information between China andthe Untied States. It would be mutually beneficial if some means could be developed to promote the exchangeof information across the Pacific Ocean. This new journal has been established for this purpose and its success willbe an important step in promoting earthquake engineering in China and the United States.     

WORLD ASSOCIATION FOR SEDIMENTATION AND EROSION RESEARCH(WASER)

正President:Giampaolo Di Silvio,Italy Vice Presidents:Ulrich C.E.Zanke,Germany Zhao-yin Wang,China The World Association for Sedimentation and Erosion Research(WASER),inaugurated on Oct.19,2004,is an independent non-governmental,non-profit organization.The mission of WASER is to promote international co-operation on the study     

Enhancing remote sensing research on global change to improve our understanding on Earth system processes

正Global Change includes climate change and other environmental changes caused by the joint interaction among various layers of Earth. From the positive side, global change provides new opportunities to human and other living forms on Earth. In the meantime, it creates tremendous challenges and negative impact. At present, the negative impacts have reached all primary processes of the global ecosystem and every aspect of human society, especially causing degradation of the ecosystem. For instance, intensive deforestation causes decline of biodiversity; global warming causes sea level rise and increases     

Solute concentrations in the lower niger river and the source rock contribution

Water quality analyses for the Niger River for the 1980/81 hydrological year are presented. The samples were collected from the main river at Lokoja, and from two main tributaries, the Kaduna and the Benue Rivers. Different water types were distinguished by the concentrations of major ions. The type Ca > Na > Mg > K - HCO₃ > SO₄ > Cl was represented at all stations during at least part of the year. Chloride was found to dominate the sulphate ion in the Kaduna and Niger, while the Benue maintained a higher concentration of sulphate relative to chloride all year round. Distinct patterns of seasonal variation in the ion concentrations were observed, particularly for the samples collected at Lokoja. Low ion concentrations were prominent during periods of high discharge, while low flow periods coincided with high dissolved ion concentrations. The contribution of rainwater to the total dissolved solids in the river waters was assessed indirectly using rainwater chemistry data from the Gulf of Guinea. The estimated rainwater contribution to the Lower Niger amounts to 5.15 mg 1^?1. Geochemical weathering calculations involving reactions of the four major minerals of granitic rocks - anorthite, biotite, albite, and K-feldspar - with carbon dioxide and water, can account for the average water composition of the Lower Niger. The proportion of the ionic components was also related to the occurrence of the respective element in the minerals.