Direct detection of ultra-trace vanadium (V) in natural waters by flow-injection chemiluminescence with controlled-reagent-release technology

A new simple, rapid, selective and sensitive analytical procedure based on chemiluminescence (CL) detection is described for the determination of vanadium (V) at sub-nanogram levels in natural waters by use of controlled-reagent- release technology in a flow injection system. The analytical reagents involved in the CL reaction, including luminal and periodate, were both immobilized on anion-exchange resins in a flow injection system. Through water injection, luminol and periodate were eluted from the anion exchange column to generate the chemiluminescence, which was enhanced in the presence of V(V). The increased CL intensity was linear with V(V) concentration in the range from 0.2 to 100 ng mL^− 1. The limit of detection was 60 pg mL^− 1 (3σ) and the relative standard deviation (RSD) was 1.45% (n = 5) for a 0.5 ng mL^− 1 V(V). At a flow rate of 2.0 mL min− ¹, including sampling and washing, a typical analytical procedure could be performed in 0.5 min with a RSD of less than 3.0%. The proposed method was successfully applied to determine vanadium in natural waters, and the results were in good agreement with those obtained by ion chromatography.     

辽北辉绿岩墙(床)群及二道沟组玄武岩锆石年龄及其构造意义

辽东半岛北部铁岭市泛河流域位于郯庐断裂北段,归属于中朝板块华北块体的东北端。此地区发育巨厚的玄武岩(二道沟组)及辉绿岩墙(床)群,过去认为系中元古代时期的基性岩浆活动。对玄武岩及辉绿岩锆石SHRIMP年龄测定,获得二道沟组玄武岩喷发定位的时间在古近纪始新世((36.4±1.8)Ma);辉绿岩浆侵位结晶时间为晚白垩世((93.5±1.4)Ma)。辽北基性岩岩浆定位年龄明确显示,分割中朝板块内部华北块体与胶辽朝块体的北部边界——郯庐断裂北段在晚白垩世处于东西向伸展拉张构造环境,导致辉绿岩侵位;古近纪发育了近南北向的拉张构造,伸展作用进一步发展,形成二道沟组巨厚玄武岩。新的SHRIMP锆石U-Pb年龄不支持辉绿岩及二道沟组玄武岩形成年代为中元古代的传统认识。     

用面积平衡原理预测伸展断陷盆地中岩层内部应变及亚分辨正断层的方法

大多数地堑和半地堑是由深度近水平的拆离正断层控制的。根据面积平衡原理,这些伸展断陷盆地岩层的区域基准面至拆离断层面高度（h）与其损失面积（S）呈线性比例。拆离断层之上的盆地基底岩层的水平伸展量相同,因此,用“S－h图解法”可以确定拆离断层深度,并能在此基础上计算出岩层的总水平伸展量。伸展盆地中的总水平伸展量主要是由不同尺度的正断层的水平离距体现出来的。可观测解释的断层的水平位移可以通过测量盆地宽度、岩层长度等直接得到。用剖面面积平衡方法可计算出盆地各岩层的平行岩层面的应变,其中相当部分是由在观测尺度上不能直接解释出来的“亚分辨正断层”的小尺度位移造成的。因此,在分析伸展断陷盆地的构造样式、岩层力学性质基础上,有可能对计算得到的平行岩层的伸展应变进行合理评估,进而可以定量地预测“亚分辨正断层”的密度和可能的分布部位。     

64层螺旋CT对穿孔及非穿孔性阑尾炎的诊断价值

目的：探讨穿孔性和非穿孔性阑尾炎的CT表现,评估CT对其诊断价值。方法：选择经临床证实的24例阑尾炎,根据病理结果将这些病例分为2组：穿孔性阑尾炎组（10例）和非穿孔性阑尾炎组（14例）。分析其CT征象并进行比较。结果：阑尾周围蜂窝组织炎、阑尾壁不连续和阑尾周围积气是穿孔性阑尾炎的直接CT征象,对穿孔性阑尾炎的诊断有很...     

Braking PSR J1734–3333 with a possible fall-back disk

The very small braking index of PSR J1734–3333,n=0.9±0.2,challenges the current theories of braking mechanisms in pulsars.We present a possible interpretation that this pulsar is surrounded by a fall-back disk and braked by it.A modified braking torque is proposed based on the competition between the magnetic energy density of the pulsar and the kinetic energy density of the fall-back disk.With this torque,a self-similar disk can fit all the observed parameters of PSR J1734–3333with natural initial values of parameters.In this regime,the star will evolve to the region having anomalous X-ray pulsars and soft gamma repeaters in the P˙P diagram in about 20 000 years and stay there for a very long time.The mass of the disk around PSR J1734–3333 in our model is about 10M⊕,similar to the observed mass of the disk around AXP 4U 0142+61.     

A Check on the Variations of Earth‘s Rotation with an Ancient Solar Eclipse

We address the relation between an ancient total eclipse, which occurred on A.D.1542 August 11 and the variation of Earth‘‘s rotation. The total eclipse was recorded in some ancient Chinese books, especially in local chronicles. Some of the documents include useful information for determining the location of the totality zone. The parameters of the eclipse are calculated by using the DE406 Ephemeris.A high-precision value of AT which expresses the variation of the Earth‘‘s rotation,of about 300 ～ 380 s, is obtained.     

天王星卫星的CCD观测与分析解的比对

本文给出了处理天王星卫星ＣＣＤ图象位置资料的新方法,并将我们在１９９５年取得的重要资料与两种理论模型位置进行了比较计算,结果表明经处理后的天王星五颗主要卫星ＣＣＤ观测精度有了较大提高。     

How can FAST improve study of the pulsar emission mechanism and magnetospheric dynamics?

The Five-hundred-meter Aperture Spherical radio Telescope(FAST) has the potential to discover many new pulsars and new phenomena. In this paper we mainly concentrate on how FAST can impact study of the pulsar emission mechanism and magnetospheric dynamics. Several observational programs heading to this direction are reviewed. To make full use of the superior performance of FAST and maximize the scientific outcome, these programs can be arranged in different phases of FAST according to their demands for observational conditions. We suggest that programs can be performed following the test phase, which are observations of multifrequency mean pulse profiles, anomalous X-ray pulsars(AXPs)/soft gamma-ray repeaters(SGRs), mode changing, drifting subpulse and nulling. The long-term monitoring can be carried out for mode changing, AXPs/SGRs and precessional pulsars. Others programs, including polarization observations of radio and γ-ray pulsars, searching for weak pulse components, and multifrequency observations of subpulse drifting, microstructure and giant pulses, can be conducted in all the normal operating phases(the first and second phases). These programs will push forward the frontier in this field in different respects. The search for sub-millisecond pulsars and follow-up observations of their emission properties are very important projects for FAST, but they may be covered by other papers in this mini-volume; therefore,they are not discussed here.     

2006年6月28日河南省强对流天气过程分析

利用濮阳、三门峡新一代天气雷达产品及云图、自动站等资料,分析了2006年6月28日河南省强对流天气过程。结果表明:濮阳新一代天气雷达基本反射率明显特征为弓形带状回波,对应径向速度上为一条明显的辐合线,强降水回波带和此中尺度辐合线位置吻合;三门峡新一代天气雷达显示,洛宁冰雹的组合反射率达65dB z,回波顶高达14~17 km,垂直液态含水量达55~65 kg.m-2,径向速度产品显示有中尺度气旋,以上特征早于降雹30 m in左右出现。     

基于GIS的矿井水害预测系统研究

在分析矿井突水影响因素的基础上,应用信息化手段集成GIS组件技术创建了突水预测模型库,实现了突水点预测、突水危险性分区、区域预测和顶板突水预测。运用该系统对平顶山煤业集团公司五矿首采区庚-采区突水危险进行了全面评价,认为在露头附近存在突水危险性,进而有针对性采用地面物探、井下超前探测以及帷幕注浆等综合防治水措施。经过治理,突水点涌水量由350m3／h减少为40～60m3／h,不仅保证了安全生产,还解放了庚组煤炭储量573．2万t。