对等辐照方位与建筑朝向的选择

本文计算并分析了墙面可照时间和天文辐射日总量及其随坡向的分布,从中发现,存在东西对称的方位,在该方位上墙面的可照时间或天文辐射日总量在冬夏半年各自对应的太阳赤纬时都相等,称之为对等日照方位和对等辐射方位,统称为对等辐照方位,并且,在对等辐照方位以南的各方位上冬半年的可照时间（天文辐射日总量）大于夏半年对应太阳赤纬时的值,而对等辐照方位以北各方位的情况相反,因而对等辐照方位可作为适宜建筑朝向选择的临     

Development of a laboratory exposure system using marine fish to carry out realistic effect studies with produced water discharged from offshore oil production

A biotest system for environmentally realistic exposure of fish to produced water (PW) was developed and tested. Authentic PW was collected at an oil production platform in the North Sea and preserved by freezing in multiple aliquots a 25 L. After transport to the test laboratory onshore, daily PW aliquots were thawed, homogenised and administered to the test fish, Atlantic cod (Gadus morhua), in two diluted exposure concentrations, 0.1% and 0.5%, during a 15 d period, using a continuous flow-through exposure setup. Positive control groups were exposed to two crude oil treatments for comparison. Chemical analyses showed that alkylphenol (AP) and PAH concentrations in PW exposure waters were very low. Observations of significantly increased AP and PAH metabolite levels in PW exposed fish demonstrated the suitability of the biotest system for its use in biological exposure/effect studies of PW, and it also demonstrated the sensitivity of bile metabolites as PW exposure markers in fish. The relevance of the biotest system for PW effect studies and for validating modelled environmental risk estimates of PW dischargers from offshore oil production is discussed.     

Ar–Ar age and thermal history of martian dunite NWA 2737

We report an ³⁹Ar–⁴⁰Ar age determination of a whole rock sample of the olivine-rich, martian meteorite Northwest Africa (NWA) 2737. Those extractions releasing 0–48% of the ³⁹Ar define an ³⁹Ar–⁴⁰Ar isochron age of 160–190 Ma, when evaluated in various ways. Higher temperature extractions show increasing ages that eventually exceed the reported Sm–Nd age of 1.42 Ga. At least part of this excess ⁴⁰Ar may have been shock implanted from the martian atmosphere. We considered two possible interpretations of the Ar–Ar isochron age, utilizing the measured Ar diffusion characteristics of NWA 2737 and a thermal model, which relates Ar diffusion to the size of a cooling object after shock heating. One interpretation, that ⁴⁰Ar was only partially degassed by an impact event ~ 11 Ma ago (the CRE age), appears possible only if NWA 2737 was shock-heated to temperatures > 600 °C and was ejected from Mars as an object a few 10 s of cm in diameter. The second interpretation, which we prefer, is that NWA experienced an earlier, more intense shock event, which left it residing in a warm ejecta layer, and a less intense event ~ 11 Ma ago, which ejected it into space. Our evaluation would require NWA 2737 to have been heated by this first event to a temperature of ~ 300–500 °C and buried in ejecta to a depth of ~ 1–20 m. These conclusions are compared to model constraints on meteorite ejection from Mars reported in the literature. The second, Mars-ejection impact ~ 11 Ma ago probably heated NWA 2737 to no more than ~ 400 °C. NWA 2737 demonstrates that some martian meteorites probably experienced shock heating in events that did not eject them into space.     

污染场地健康风险评价的理论和方法

综合国外研究进展介绍了污染场地健康风险评价的基础理论和评价方法,基础理论主要从人体摄取污染物质的方式和机制以及污染物摄取剂量和人体健康效应的关系两方面开展讨论。评价方法从数据收集、暴露评估、毒性评估和风险表征4方面进行探讨。在此基础上,对评价方法进行了探讨,提出了“叠加风险”和“多暴露途径同种污染物累计健康风险”的概念和计算方法,分析了中国开展污染场地健康风险评价的相关问题,指出构建中国污染场地健康风险评价体系应从制定法律入手,以典型污染场地风险评价为试点,逐渐建立和完善风险评价指南和技术细则,最终完成包括法律法规、评价指南和技术细则等在内的污染场地健康风险评价体系的建立。     

Composition and origin of clay minerals in Holocene sediments from the south-eastern North Sea

The distribution of clay minerals varies systematically in sediments from Holocene core material taken along a profile from the East Frisian coast to the Doggerbank. The proportion of illite increases with distance from the coast at the expense of kaolinite, whereas slight variations are seen in smectite and chlorite abundances. The chemical composition changes, and the K/Rb ratio and K-Ar isotopic age of illite increase seawards. This trend results from progressive mixing processes of riverine detritus with Pleistocene fluvioglacial material reworked during the Holocene transgression. However, the clay fluvial flux only became dominant during the decreasing rate of sea-level rise in the Late Holocene, especially near the shore. For example, modern sediments in tidal flats contain 75% of river-borne Holocene-supplied clay detritus, whereas this amount is only 10% in modern marine sediments at the Doggerbank.     

Ar–Ar ages and geochemistry of the basaltic shield stage of Tenerife, Canary Islands, Spain

We report the first ³⁹Ar–⁴⁰Ar ages from the three early basic shield-like massifs of Tenerife, Canary islands, and couple these with detailed major and trace element chemistry to constrain the nature and timing of the mantle melting processes. The massifs have chemically different sources, and independent evolutionary histories. The Teno and Roque del Conde massifs appear chemically to represent the products of single mantle melting cycles, with progressive decrease in mean melt fraction and increase in mean melting depth in younger rocks. The Teno massif (NW) was erupted in a short time period around 6.0–6.4 Ma, while at least the lower half of the Roque del Conde massif (SW) is older than 11 Ma. In contrast, the Anaga massif (NE) is polygenetic, with ³⁹Ar–⁴⁰Ar ages ranging from 8.0–4.2 Ma, and no simple stratigraphic chemical progression. These ages run counter to published suggestions of progressive younging of Canary shield stages to the southwest. Basic rocks in all three massifs are the result of much deeper melting and smaller melt fractions than equivalent units in Gran Canaria, but nevertheless the melting column must have extended significantly into the spinel facies, requiring substantial disruption of the local lithosphere. The age and melting relationships broadly support the mantle blob model for Canary magmatism proposed by Hoernle and Schmincke (Hoernle, K., Schminke, H.-U., 1993. The role of partial melting in the 15-Ma geochemical evolution of Gran Canaria: a blob model for the Canary hotspot. J. Petrol. 34, 599–626). In all three massifs, extensive fractional crystallisation has taken place at crustal levels so that mean MgO contents are only some 6–7%. The fractionation sequence is olivine–clinopyroxene–magnetite in basaltic compositions, with the involvement of plagioclase, amphibole and apatite only to generate the infrequent more evolved hawaiites to benmoreites. Despite the abundance of basanitic magmas in the Tenerife older massifs, these follow a differentiation trend towards weakly undersaturated benmoreite rather than to phonolite. This probably reflects early crystallisation of magnetite, perhaps resulting from somewhat high oxygen fugacity. The chemical evidence for replenished magma chambers in Tenerife described by Neumann et al. (Neumann, E.R., Wulff-Oedersen, E., Simonsen, S.L., Pearson, N.J., Martí, J., Mitjavila, J., 1999. Evidence for fractional crystallisation of periodically refilled magma chambers in Tenerife, Canary Islands. J. Petrol. 40, 1089–1123) is a consequence of treating as a single cogenetic suite the products of several magmatic systems that differ in parental melt fraction.     

非均匀风沙起动规律研究

文章将非均匀沙水流起动研究方法中采用的暴露度的概念引入到天然风沙起动的研究中, 对暴露度的统计规律进行了分析。利用风沙颗粒起动时力矩平衡的条件, 建立了天然风沙起动公式, 用风洞试验资料进行了验证。计算结果表明, 在非均匀沙起动粒径与平均粒径相当的条件下, 混合沙的起动风速较小的结论, 与实际情况相符。说明在天然风沙起动研究中采用暴露度来反映风沙不均匀性对起动的影响是合理的。     

海南岛鹿回头造礁珊瑚的14C年代及珊瑚礁的发育演化

通过2002年7月沿鹿回头珊瑚礁坪断面方向,在原生滨珊瑚(Porites)礁表面进行系统采样,并进行C测年和年代校正,初步划分出全新世以来珊瑚礁演化的5个阶段珊瑚礁繁盛期(7 300-6000cal.aBP)、珊瑚礁发育停滞期Ⅰ(6 000-4 800cal.aBP)、珊瑚礁发展期(4 800-3000 cal.aBP)、珊瑚礁发育停滞期Ⅱ(3 000-1000 cal.aBP)和现代珊瑚礁发育期(1 000cal.aBP以来).鹿回头珊瑚礁在7 300-000cal.aBP处于发育的繁盛期,己基本上形成了现代珊瑚礁的地貌格局.后来不同时期珊瑚礁是在此时期形成的礁塘或礁坑等低洼地中形成,并在鹿回头半岛两侧向外发展,现代珊瑚礁则发育于全新世珊瑚礁的外礁坪或礁前斜坡带.     

广东高温热浪致人体健康风险区划

本文采用国际上通用的自然灾害风险概念和分析方法,从高温热浪致人体健康风险的构成出发,分别构建了广东省高温热浪危险性指数、暴露度指数和承灾体脆弱性指数（含敏感性指数和适应性指数）,在定量化的风险指数基础上尝试进行风险区划研究。结果表明：高危险性区域位于广东东北部、西北部以及中部偏西地区,低危险性区域主要分布在沿海地区;人体健康高敏感性区域主要位于粤北和粤西,珠三角及粤东南沿海地区敏感性相对较低;适应性较高区域主要分布在珠三角地区,其他地区适应性较低,粤东和西南部分地区适应性最低;风险较高区域主要集中在粤东、粤西北和中部偏西及雷州半岛南部地区,风险较低区域主要在珠江三角洲及其以西沿海地区。该风险指数能较好地反映广东省高温热浪致人体健康风险的分布状况。