黄河兰州断面半挥发性有机污染物分布特征研究

用固相萃取和液液萃取的方法对黄河兰州断面的水样品进行预处理,再进行气相色谱／质谱联用分析测定,对饮用水源水中的半挥发性有机物进行了测定,并对结果进行了讨论。     

山西前兆台站水位模拟与数字观测对比分析

对山西省前兆水位观测点介休、孝义、祁县、静乐与朔州并行的模拟与数字水位观测资料,从数据完整性进行对比,运用相关性分析对数据的一致性进行检验,与气压进行相关性分析,记录地震的能力进行对比。发现,数字观测优于模拟观测,可以替代模拟观测。     

首都圈断层形变与重力场动态变化分析

本文利用首都圈跨断层形变观测和观测场地的综合调研结果, 对跨断层基线、 水准各测项的综合效能进行评估, 对断层整体活动信息进行分析提取, 对首都圈地区强震的映震效能进行分析研究。 利用首都圈地区流动重力区域测网的观测结果, 分析重力场动态变化特征, 对近期首都圈地区的地震趋势进行预测。     

上海环球金融中心结构简化弹塑性时程分析及试验验证

鉴于上海环球金融中心结构体系及结构布置的复杂、结构高度及体型的超限,为了确保该建筑结构的抗震安全性和可靠性,除进行常规的计算分析外,还应对该结构进行弹塑性时程分析。本文建立了该结构的弹塑性时程分析简化模型,并编制了相应的计算程序。为了检验结构弹塑性时程分析的可靠性,首先对振动台试验的模型结构进行弹塑性时程分析,以便和试验数据进行对比。在此基础上对原型结构进行弹塑性时程分析,并对该结构进行了抗震性能评价。     

煤田地质工程中钻孔岩心的地质特征与构造以及结构变化

在煤田勘探中进行钻孔取样是一种重要的技术措施,借助相关地质学的研究成果对岩心中的岩石特征及结构变化、构造等进行分析。文章主要根据煤田地质钻孔岩心中的岩石特性及结构变化,进行地层与构造的分析,从而对断层的存在、形态以及性质等进行分析。     

结构模糊控制规则优化生成的遗传算法

本文采用实数个体编码解码、两点交叉、两点变异、保留最优个体的模糊遗传算法对模糊控制规则进行优化;其次,对三层框架结构的模糊遗传算法控制进行了仿真实验,同时,与经验规则的模糊控制效果进行了比较;最后,对结构模糊遗传算法的鲁棒性进行了仿真试验,进一步验证了本文所提方法的可行性和有效性.     

香港青马大桥在交通荷载作用下的疲劳评估

在全桥三维有限元模型基础上 ,进行了车载响应分析 ,得到全桥的动力响应 ,并与实测结果进行了分析对比 ;对疲劳危险部位建立局部有限元模型 ,并进行了局部应力分析。在结构健康安全监测系统实测数据基础上 ,得到应变循环标准块 ,用基于热点应力疲劳评估方法对危险部位进行了疲劳寿命评估。     

基于潜水层研究钻孔应力-应变对降雨的响应

钻孔应力-应变观测是在地表下数十米的基岩中(或土层中)安装仪器探头对地震应力-应变前兆变化进行观测;但仍存在环境因素影响如降雨,如进行辅助地下水位观测的钻孔应力-应变观测消除降雨的影响,主要是通过降雨引起地下水位的变化来进行分析研究并消除降雨影响,其方法为拟合相关分析、运用岩土应力-应变理论建 立模型进行研究等;无地下水位观测资料的钻孔应力-应变消除降雨影响研究不多,主要是进行简单相关分析或运用岩上应力-应变理论进行定性分析.     

地震属性优化及物性参数反演的一种非线性处理方法

常规地震资料解释方法误差较大,越来越不能满足现代地震勘探解释的需要.本文在对地震属性进行模式分类的基础上,利用LLE算法对地震属性进行非线性降维,然后利用小波BP网络对物性参数进行非线性反演,建立了一个具有自适应、复杂非线性的地震属性储层反演模型.以某工区为例进行计算,并对其精度进行检验,获得明显优于常规方法的地质效果,具有一定的实用价值.     

基于MATLAB的前兆数据异常分析系统的研制

基于MATLAB编程,针对本地区多学科的固体潮观测数据的异常情况,设计多种方法进行分析计算,以期对固体潮变化中的特殊形态等异常情况进行提取,并设计人性化交互界面,易于使用,减少出错机会,多方面对观测数据进行有效分析。     

Historische Entwicklung einer Sedimentbelastung: Gedächtnis einer Industrieregion Historical Trends of Sediment Loads: Memory of an Industrial Region

The chronologies are shown of sediment load on the banks of a river of the Ruhr district (Lippe) with radionuclides of radium, lead and cesium and preliminary chemical measurements for lead, zinc, arsenic, mercury, cadmium, barium, PAHs, PCDDs, PCDFs, PCBs, TOC, AOX and EOX. A new method of dating is developed and proved, which is especially suitable for rivers with radioactivity from coal mines. The method improves the well-known excess-²¹⁰Pb-dating for the use with rivers in industrial regions and allows the preparation of load histories (chronologies). Conclusions are made on the historical trend of emissions in the region from the trend of the sediment load of known age and regular sedimentation without perturbation.     

Investigations on Mineralogical and Chemical Composition of Suspended Particulate Matter (SPM) in the Odra Estuary

In order to recognize lateral and seasonal variations in composition of suspended particulate matter (SPM) in the Odra Estuary, samples were taken at four sites in the period July 1996 - July 1997 monthly if possible. The contents of the elements Si, Ti, Al, Fe, Mn, Mg, Ca, Na, K, P, C, S as well as Ba, Cr, Sr, V, Zn, Cu, Zr, and of the minerals illite, chlorite, smectite, kaolinite and others have been determined. The decreasing influence of the river Odra towards the open sea could be realized with the help of the contents of the minerals quartz, smectite, and of the elements Ba, Cr, K, P, Si and other. 60% of the seasonal and lateral variations can be explained by changing contents of total carbon (TC), total organic carbon (TOC), Al, Fe, Si, Ti, P, Mn, and Ba. They are mainly caused by differences in the production of organic matter, resuspension, riverine input, and redox-sensitive processes.     

Distribution and Chemical Forms of Heavy Metals in the Flood 1997 Sediments of the Upper and Middle Odra River and its Tributarie:, Poland

At the beginning of August 1997, 72 samples of flood sediments were taken along the Upper and Middle Odra river and its tributaries. The concentrations of Zn, Pb, Cu, Cd, Co, Ni, Cr, Mn, and Fe in the bulk samples and in the <20 μm fraction were determined by AAS method. The contents of metals vary in wide ranges and are significantly higher in the <20 μm fraction of sediments. The range concentrations vary as following: Zn 274...3 656 mg/kg, Pb 79...1 773 mg/kg, Cd 1.7...11.8 mg/kg, Cu 38...2 244 mg/kg, Cr 14...384 mg/kg, Co 4...73 mg/kg, Hg 0.2...3.9 mg/kg, Mn 214...6 972 mg/kg, and Fe 1.5...16.3 %. The highest amount of the metals was found in the Wrocław and Głogów regions. The mobile (exchangeable and carbonatic fractions) portions of metals reached up to 50 % of Zn, 40 % of Pb and Cu and 60 % of Mn.     

基于分子标记的藻类鉴定研究进展

藻类鉴定被广泛应用于藻类遗传学、生理学、生态学和应用藻类学,尤其是藻类调查和评估.然而,基于形态学的鉴定往往因为分类特征未出现或不典型、设备限制和人员经验欠缺等原因带来较大误差.随着测序技术的不断发展,分子标记已成为藻类鉴定的一个通用工具.由于藻类类群众多且差异很大,分子标记的选择成为藻类鉴定的关键.本文综述了蓝藻、硅藻、绿藻、甲藻、裸藻、隐藻、金藻、黄藻、红藻和褐藻等主要门类分子标记的选择及应用进展,包括分子标记选择原则、常用标记和相应序列数据库,以及各个分子标记在不同类群应用中的优缺点等.藻类分子鉴定源于编码核糖体RNA的基因（rDNA）,发展于细胞核、线粒体、叶绿体DNA等.然而,当前藻类分子鉴定逐渐细化和完善,单一的核糖体DNA、内转录间隔区（ITS）和保守蛋白编码基因等短序列分子标记已经很难满足藻类鉴定的需求,多标记组合成为一种必然选择.同时,线粒体基因组、叶绿体基因组、核基因组、转录组和宏基因组等提供了更多遗传进化信息,弥补了短序列分子标记在系统分类应用中的不足.对于藻类鉴定,单纯依赖分子标记或形态学都不足以保证鉴定的准确性,采用将分子生物学、形态学、生理生化学等结合的多相学方法,才能准确地完成鉴定工作.此外,藻类分子数据库的建立和完善是未来分子鉴定的重要工作,快速鉴定方法也必将在未来获得广泛的应用和发展.     

地球去气作用

利用地质学、天文学、地球物理学、古生物学资料进行约束,对地球的去气作用进行研究发现：太阳系的部分冷物质,通过吸积作用形成早期地球.在碰撞动能转变的热能作用下,造成了早期地球的表面熔融.在熔融状态的高温高压作用下,构成地球表面物质的结晶水排出地表进入原始大气;在高温高压下分解的碳酸盐、硫酸盐、卤化物等产生的二氧化碳、硫化氢、二氧化硫、氯化氢、氟化氢等气体进入原始大气,和水蒸汽一道共同组成原始大气.当地球内部在重力势能和放射能的作用下继续熔融时,地球表面固化为原始岩石圈.后来,地球除表面岩石圈外,整个地球完全熔融.地球内部物质熔融形成的水和二氧化碳等气体,被岩石圈圈闭.只有当冰川形成和消融,引起造海和造陆作用,导致火山喷发和地震时,这些气体才可能排出地表.这些气体的排出,受地球内部的熔融状态、冰川形成的位置（是在海洋或是在陆地）、生物的演化、太阳光的强度等因素的综合影响.     

Dating desert pavements – First results from a challenging environmental archive

Desert pavements are widespread landforms of arid environments. They consist of a monolayer of clasts at the surface, associated with an underlying unit of eolian fines. In some situations, buried desert pavements can be observed, which is interpreted as a change in the environmental conditions. Therefore, it is believed that desert pavements represent important paleoenvironmental sediment archives, especially for arid environments, where natural archives of past environments are rare. To better understand the formation process of desert pavements and to enable the paleoenvironmental interpretation of these valuable sediment archives, reliable chronologies are of crucial importance. Thus, OSL dating was applied to samples from well-developed desert pavements in two different study areas, the Cima Volcanic Field, eastern Mojave Desert, USA, and the desert of northeastern Badia, Jordan. To test the suitability of the sediments for OSL dating, the luminescence characteristics of the fine- and coarse-grain quartz fraction are described and compared. Finally, first OSL ages are presented.     

Endocrine Disrupters in the Aquatic Environment: An Overview

Although a relatively new area of environmental research, the field of endocrine disruption has grown very rapidly, and currently many hundreds, perhaps even a few thousand, papers are published annually on the many different aspects covered by the field. As far as endocrine disruption in wildlife is concerned, most attention has been focused on aquatic organisms, for two reasons. Firstly, the aquatic environment receives most of the pollutants intentionally released into the environment, through effluents from wastewater treatment plants, and secondly because many of the best documented examples of endocrine disruption in wildlife are of partially or completely aquatic species. These two reasons are probably not unconnected, of course. Hence, aquatic organisms can receive continuous exposure to endocrine‐disrupting chemicals throughout their lives, albeit usually to low concentrations of these chemicals. Analysis of effluents has identified many of the endocrine‐disrupting chemicals present, and shown that these are both natural and man‐made, and vary greatly in potency. Most attention has been directed to identifying the main estrogenic chemicals, because many of the effects reported in wildlife appear to be a consequence of ‘feminization’ of males. However, chemical analysis of effluents has also demonstrated that chemicals with other types of endocrine activity are present, such as androgens, anti‐androgens, progestagens, etc. The effects (if any, of course) of such chemicals on aquatic organisms are unknown, and largely uninvestigated, presently. Much of the biological research has centred on the effects of estrogenic chemicals, especially to fish. These effects, such as elevated vitellogenin concentrations and intersexuality, have to date been studied almost exclusively at the level of the individual, and hence whether endocrine‐disrupting chemicals cause population‐level consequences is largely unknown (the undeniable effects of TBT on molluscs, leading to local extinctions, being the exception). It is my opinion that rather too much of the recent research has not advanced our understanding of endocrine disruption a great deal, and we are probably not much further forward now than we were five years or so ago. It is surely time to tackle some of the outstanding, unresolved issues, such as the impact of endocrine disruption at the population level, and the issue of how organisms respond when exposed to complex mixtures of endocrine active chemicals. Such research will not be easy, and will require multidisciplinary teams, including people with expertise in areas not yet involved in the field of endocrine disruption, such as mathematical modellers. However, until such research is done, it will not be possible to decide how important an issue endocrine disruption is to wildlife, and how that importance compares to the other factors adversely affecting wildlife, such as habitat loss, climate change, and the introduction of exotic species and novel diseases.     

SENSITIVITY OF AQUATIC ECOSYSTEMS TO CLIMATIC AND ANTHROPOGENIC CHANGES: THE BASIN AND RANGE,AMERICAN SOUTHWEST AND MEXICO

Variability and unpredictability are characteristics of the aquatic ecosystems, hydrological patterns and climate of the largely dryland region that encompasses the Basin and Range, American Southwest and western Mexico. Neither hydrological nor climatological models for the region are sufficiently developed to describe the magnitude or direction of change in response to increased carbon dioxide; thus, an attempt to predict specific responses of aquatic ecosystems is premature. Instead, we focus on the sensitivity of rivers, streams, springs, wetlands, reservoirs, and lakes of the region to potential changes in climate, especially those inducing a change in hydrological patterns such as amount, timing and predictability of stream flow. The major sensitivities of aquatic ecosystems are their permanence and even existence in the face of potential reduced net basin supply of water, stability of geomorphological structure and riparian ecotones with alterations in disturbance regimes, and water quality changes resulting from a modified water balance. In all of these respects, aquatic ecosystems of the region are also sensitive to the extensive modifications imposed by human use of water resources, which underscores the difficulty of separating this type of anthropogenic change from climate change. We advocate a focus in future research on reconstruction and analysis of past climates and associated ecosystem characteristics, long-term studies to discriminate directional change vs. year to year variability (including evidence of aquatic ecosystem responses or sensitivity to extremes), and studies of ecosystems affected by human activity. © 1997 John Wiley & Sons, Ltd.     

南四湖地区水环境问题探析

末次盛冰期（ＬＧＭ）是太阳辐射异常处于极低值,北半球第四纪冰流规模处于峰值,两万年来距人类环境最近但与现代气候有着巨大反差的特殊时期,７０年代以来由于新资料不断积累,气候模拟技术发展,海洋大陆冰流各圈层的相关和偶合,传统的气候指标和新的气候指标的认识和应用,以及区域性和全球性的国际合作,在ＬＧＭ古气候环境领域已经取得了巨大进展,本文根据数个国际ＬＧＭ合作计划研究成果,综述９０年代以来全球对ＬＧＭ研