Møre Margin: Crustal structure from analysis of Expanded Spread Profiles

Analysis in both the x—t and —p domains of high-quality Expanded Spread Profiles across the Møre Margin show that many arrivals may be enhanced be selective ray tracing and velocity filtering combined with conventional data reduction techniques. In terms of crustal structure the margin can be divided into four main areas: 1) a thicker than normal oceanic crust in the eastern Norway Basin; 2) expanded crust with a Moho depth of 22 km beneath the huge extrusive complex constructed during early Tertiary breakup; 3) the Møre Basin where up to 13–14 km of sediments overlie a strongly extended outer part with a Moho depth at 20 km west of the Ona High; and 4) a region with a 25–27 km Moho depth between the high and the Norwegian coast. The velocity data restricts the continent-ocean boundary to a 15–30 km wide zone beneath the seaward dipping reflector wedges. The crust west of the landward edge of the inner flow is classified as transitional. This region as well as the adjacent oceanic crust is soled by a 7.2–7.4 km s^–1 lower crustal body which may extend beneath the entire region that experienced early Tertiary crustal extension. At the landward end of the transect a 8.5 km s^–1 layer near the base of the crust is recognized. A possible relationship with large positive gravity anomalies and early Tertiary alkaline intrusions is noted.     

TRMM PR雷达与阜阳雷达降水资料的对比研究

选取了1998年与1999年HUBEX观测资料，将TRMM卫星上的星载降雨雷达PR与阜阳的713数字化天气雷达资料在以下3个方面做了比较：(1)强度场的分布；(2)平均反射率廓线；(3)灵敏度。分析、比较结果可知阜阳雷达在探测灵敏度和水平方向的分辨率要高于PR，但由于波束宽度、衰减和资料转化过程计算误差的原因，其远距离处的观测值与真实值有一定偏差。PR波长短，对衰减敏感，尤其是在垂直方向上经过强衰减后，订正值仍偏小。但由于探测方式的不同PR在水平方向上不存在衰减的问题，且其资料分布均匀，因此提出一种用PR资料来订正地基雷达资料的方法用以提高地基雷达探测的精确度。     

江苏南部两次暴雨-大暴雨过程分析

2011年6月10日(简称“11·06”)和2017年6月10日(简称“17·06”)在江苏南部出现了两次暴雨-大暴雨过程,本文利用常规观测资料、FNL再分析资料和雷达资料等,对两次过程进行了分析,结果表明:异常的高低纬度环流形势配合,为强降水的发生提供了有利的环流背景。两次过程代表站的物理量场差异较大:“17·06”最大散度值约为“11·06”的2倍;“17·06”最大垂直速度、最大水汽通量散度值约为“11·06”的1.8、1.3倍且大值维持时间均很长。两次过程均为暖区低质心热带海洋型强降水,但“11·06”强回波分散、伸展高度偏低、强度偏弱且无明显强回波的列车效应;“17·06”强回波排列紧密、伸展高度高、强度明显偏强且强回波列车效应明显。螺旋度变化一般提前于降水变化,具有可预报性,可作为大面积降水开始—维持—结束的一个短时(临近)预报因子。VWP产品中大风区底高的变化,有助于判断雷达站附近降水的变化趋势。     

恒星的非径向脉动和模式证认

介绍了恒星非径向脉动的一般特性和可观测特征．着重评述早型恒星非径向脉动研究的最新进展以及非径向脉动模式证认的各种方法．     

Konzentrationsprofile in Rotationsscheibenreaktoren und deren Modellierung am Beispiel des anaeroben Acetatabbaus mit experimenteller Überprüfung

Concentration Profiles in Rotating Disc Reactors. Their Mathematical Model for the Anaerobic Digestion of Acetic Acid Including an Experimental Verification This paper presents rotating disc reactors for aerobic and anaerobic wastewater treatment. Unlike the activated sludge or contact processes, this reactor allows higher concentrations of biomass and lesser danger of the reactor becoming blocked. The reduced backmixing within the reactor leads to axial concentration profiles when continuously operated. These are presented for various biological processes. The axial concentration profiles generated during the continuous anaerobic degradation of acetic acid are measured and described by a mathematical model. A refined dispersion model is created on the basis of tracer experiments taking into account the actual construction of the reactor as well as the physical conditions in it. To determine the biodegradation a Haldane kinetics is used, in which the undissociated acetic acid is the substrate. The model takes into consideration all the local parameters (pH value, concentration of acetic acid, biomass, and ion activity). The difficult measurement of the concentration of the active biomass which is immobilized on the disk is accomplished by carrying out batch experiments. The results of the experiments are 22 concentration profiles with influent DOC concentrations from 200 to 2000 mg L^–1 which were measured and modelled. Some examples are shown to illustrate the influence of the ion activity and the refinement of the dispersion model.     

Distribution of coastal cliffs in Kerala,India: their mechanisms of failure and related human engineering response

The 560-km-long Kerala coast is characterised by long barriers with narrow beaches and steep cliffs. Distribution of cliffs from nine sections measuring a cumulative length of 63.5 km is evaluated in ArcGIS Software using topomaps and field survey data. The cliff sections in the southern coast comprise both permeable and impermeable rocks, whereas those along northern coast are comprised of either Precambrian crystalline and/or Tertiary formations. Notches, caves and even small arches are developed in Cannanore, Dharmadam and Kadalundi cliffs, where only primary laterites are exposed to wave attack. Stacks composed of laterite and Precambrian crystallines found in nearshore of cliffed coast indicate recession of shoreline. Mass wasting, mudslide and mudflow type of cliff failures are common in permeable to semi-permeable rocks, whereas rotational sliding, rockfall and toppling failure are found in hard rock cliffs. Retreat of cliff sections are induced by natural or anthropogenic activities or both. Rate of recession vary from a few centimetres to one metre/year depending upon the nature of lithology, structures and recession agents acting upon the cliffs. Various methods of cliff protection for e.g. hard structures—revetments, groins, seawalls, breakwater and jetties—and soft measures—artificial reefs/marsh creation, floating breakwaters, beach nourishment, beach scraping and vegetation planting—are suggested.     

Polychlorierte Dibenzo-p-dioxine, -furane (PCDD/F) und Analoga in Oberflächensedimenten und datierten aquatischen Sedimentkernen

Polychlorinated Dibenzo-p-dioxins, -furans (PCDD/F) and Analogues in Surface Sediments and Dated Aquatic Sediment Cores Aquatic sediments are the final sinks of unintentionally formed PCDD/Fs. Still not known are the conditions of formation of PCDD/Fs in the 8120 years old sediments in Japan and in 350 to 400 years old sediments in the Baltic. Sediments are means of source identification if transformation processes are taken into consideration in view of hydrological conditions. PCDD/Fs have been analysed 30 km from the source in sediments and over a distance of 50 km in benthos indicating a remarkable bioaccumulation potential. Elaborated data of the PCDD/F sediment contamination are missing as well as information on internal diagenetic processes, interactions at the sediment/water interface, and on the aerobic and anaerobic biodegradation and bioavailability of PCDD/Fs in sediments. Quality criteria for sediments and aquatic ecosystems remain to be elaborated.     

Erratum: the 2.27 day period of WR-134 (HD 191765)

The original temporal analysis of a 12 night spectral timeseries of WR-134 has been found to be flawed and a re-analysis shows that the line profile variations are indeed periodic. When combined with a 4 night timeseries taken 45 days earlier, a period near 2.27 d is found in periodograms of the Heii 5412 line centroid,rms line width, and line skew variations. When the emission line residuals are ordered as a function of phase, a sinuous feature appears to snake about the line center with an amplitude of ± 500 km s^–1. This is 20 larger than the line centroid amplitude; the calculation of which is heavily weighted by static portions of the line profile. In addition to the snake, emission residuals appear that move away from line center on unbound trajectories and are thought to result from the interaction of a periodic driver with the unstable flow of the radiation driven wind. The nature of the periodic driver is a topic for discussion.