Adsorption of phosphate from the Yellow River water by desert particles: Kinetics and equilibrium studies

The equilibrium and kinetic adsorption of phosphate (P) from the Yellow River water onto desert particles taken from the Ulan Buh and Kubuqi deserts were investigated. Effect of the initial concentration of P and particulate matter on the sorption was explored. The kinetic studies show that adsorption rate was faster within the 0–8th hour period, then gradually decreased at 8th–48th hour period and basically tended to a dynamic equilibrium at the 48th hour, but there exists an adsorption difference of P onto different desert particles. The uptake process of P followed the pseudo-second-order rate model and the Morris-Weber diffusion equation which indicates that the adsorption process was mainly controlled by P diffusion inside the particles. The equilibrium investigation obtained an adsorption-desorption equilibrium mass concentration (EPC₀) of P from the Yellow River water on desert particles with the range of 0.010–0.042 mg/L, which is higher than present P concentration in the Yellow River. This study indicates that desert particles entering the river might release P to the Yellow River.     

Brightness temperature for 166 radio sources

Using the database of the University of Michigan Radio Astronomy Observatory （UMRAO） at three radio frequencies （4.8, 8 and 14.5 GHz）, we determined the short-term variability timescales for 166 radio sources. The timescales are 0.15d （2007＋777） to 176.17 d （0528-250） with an average timescale of Atobs = 17.1 4- 16.5 d for the whole sample. The timescales are used to calculate the brightness temperatures, TB. The value of log TB is in the range of log TB = 10.47 to 19.06 K. In addition, we also estimated the boosting factor for the sources. The correlation between the polarization and the Doppler factor is also discussed.     

乌鲁木齐河洪水变化趋势分析

主要依据英雄桥水文站实测洪水资料对乌鲁木齐河洪水时空变化特性进行简略分析,通过多种方法分析了乌鲁木齐河49a来洪水的变化趋势。结果表明进入20世纪90年代年最大洪峰流量偏离平均值幅度较大,从1993年开始进入大洪水多发期,且大洪水出现频次增加。     

跨座式单轨交通沿线雷电活动规律与易闪性分析

采用线路走廊法,利用重庆市2006～2008年ADTD地闪监测资料,通过对重庆市跨座式单轨交通2号线的雷电活动规律(闪电次数、雷电日、地闪密度、雷电流幅值分布和闪电落区分布)统计分析,进行了相应的易闪性分析.结果发现跨座式单轨交通2号线临江门至佛图关车站区间段是发生临界危险雷电流概率、雷击大地年平均密度较大和雷电落区距离各站点及区间平均距离较小的重叠区域,该线易受雷击,是雷电防护重点区域.该区间段处于沿江位置,地形较为陡峭,易导致局地强对流性天气,理论分析与实际情况一致.     

Using the OSPM Model on Pollutant Dispersion in an Urban Street Canyon

An observational campaign was conducted in the street canyon of Zhujiang Road in Nanjing city in 2007.Hourly mean concentrations of PM10 were measured at street and roof levels.The Operational Street Pollution Model(OSPM)street canyon dispersion model was used to calculate the street concentrations and the results were compared with the measurements.The results show that there is good agreement between measured and predicted concentrations.The correlation coecient R2 values(R2 is a measure of the correlation of the predicted and measured time series of concentrations)are 0.5319,0.8044,and 0.6630 for the scatter plots of PM10 corresponding to light wind speed conditions,higher wind speed conditions,and all wind speed conditions,respectively.PM10 concentrations tend to be smaller for the higher wind speed cases and decrease rapidly with increasing wind speed.The presentations of measured and modelled concentration dependence on wind direction show fairly good agreement.PM10 concentrations measured on the windward side are relatively smaller,compared with the corresponding results for the leeward side.This study demonstrates that it is possible to use the OSPM to model PM10 dispersion rules for an urban street canyon.     

GPON光纤技术在山东地震信息网络中的应用

简要介绍了山东省地震行业信息系统的组成和功能,以及新建系统的项目背景、建设需求。介绍了光纤通信的发展历程,Epon和Gpon技术的基本原理及优、缺点和采用光纤组网的技术优势,以及结合山东省地震局信息系统实际和今后业务的发展规划。同时考虑了如何设计、技术思路和实施方案,以使该设计思路和方案最大程度的发挥优势。     

北大巴山志留系滔河口组碱质斑状玄武岩的岩浆源区及形成环境——来自全岩和辉石斑晶地球化学的约束

北大巴山志留系滔河口组火山-沉积地层发育有粗粒玄武岩、细粒玄武岩、杏仁构造玄武岩和枕状玄武岩四种斑状玄武岩相。它们都属于碱性玄武岩,并具有相似的地球化学特征,富Ti、贫Si,富集大离子亲石元素(LILE,如Th、Rb、Ba)和LREE,轻重稀土分异明显。稀土和微量元素标准化配分型式具有与洋岛玄武岩(OIB)类似的特征。斑晶主要属于单斜辉石族中的次透辉石-透辉石,具有与全岩相似的微量和稀土元素配分形态,表明四种玄武岩相由同一岩浆源区形成。由单斜辉石-熔体平衡温压计计算获得的初始岩浆深度大于67.65km,表明岩浆源区来自地幔。岩浆在上升过程中在39.93～67.65km、14.52～20.46km、4.62～9.24km三个深度范围发生了储积结晶,最后喷出到地表分别形成粗粒玄武岩、细粒和枕状玄武岩、杏仁构造玄武岩。粗粒玄武岩中富含金云母表明岩浆源区遭受了富不相容元素流体的交代作用。玄武岩全岩、单斜辉石地球化学特征以及火山-沉积序列共同表明,滔河口组碱性玄武岩形成于大洋板内环境。     

氢化物发生-原子荧光光谱法测定土壤中水溶态和可交换态锑(Ⅲ)和锑(Ⅴ)

在0.10 mol/L酒石酸介质中,采用氢化物发生-原子荧光光谱法测定土壤中水溶态和可交换态Sb(Ⅲ)和Sb(Ⅴ)。以氢气发生器为氩-氢火焰提供氢气,明显降低了硼氢化钾浓度,改善了测定检出限。考察了酒石酸掩蔽Sb(Ⅴ)的量及共存干扰元素的允许量。方法检出限Sb(Ⅲ)为0.026 ng/L,总Sb为0.019 ng/L。加标回收试验表明,方法准确、可靠。     

微波萃取-气相色谱/气相色谱-质谱法测定土壤中18种有机氯农药

采用微波萃取-Florisil固相萃取柱净化分离、气相色谱和气相色谱-质谱相结合的方法测定土壤中的痕量半挥发性有机氯农药。优化了微波萃取和固相萃取柱净化条件,在最优条件下18种有机氯农药(α-HCH、β-HCH、γ-HCH、δ-HCH、七氯、艾氏剂、环氧七氯、硫丹Ⅰ、p,p′-DDE、狄氏剂、异狄氏剂、硫丹Ⅱ、p,p′-DDD、o,p′-DDT、异狄氏剂醛、硫丹硫酸酯、p,p′-DDT、甲氧滴滴涕)的回收率在89.56%~114.22%。对气相色谱和气相色谱-质谱法的仪器检出限、回收率、精密度和方法检出限进行对比,确定了采用气相色谱-质谱定性和气相色谱定量相结合的方法,测定实际土壤样品中的有机氯农药,使得定性和定量的准确度都得到提高。     

长江上游夏季径流量年际增量预测模型及检验

基于1980-2020年长江上游夏季径流量、降水和气温等资料,采用小波分析、最优子集回归等方法,分析径流量、降水量和气温的变化关系,探讨引发径流量变化的前兆气候异常信号,并构建径流量年际增量预测模型.结果 表明:径流量多寡直接取决于流域总降水量,两者表现出显著的准两年周期振荡特征,年际增量之间的相关系数(TCC)为0....