Properties of iron alloys under the Earth's core conditions

The Earth's core is constituted of iron and nickel alloyed with lighter elements. In view of their affinity with the metallic phase, their relative high abundance in the solar system and their moderate volatility, a list of potential light elements have been established, including sulfur, silicon and oxygen. We will review the effects of these elements on different aspects of Fe–X high pressure phase diagrams under Earth's core conditions, such as melting temperature depression, solid–liquid partitioning during crystallization, and crystalline structure of the solid phases. Once extrapolated to the inner–outer core boundary, these petrological properties can be used to constrain the Earth's core properties.     

云南地区波速比异常图像的南北差异

动态追踪了云南地区第4 强震活跃期6 .3 级以上强震前波速比异常图像,显示出明显的南北差异:滇西南的1988 年11 月6 日澜沧- 耿马7 .6 、7 . 2 级和1993 年1 月27 日普洱6 .3 级强震发生在低波速比异常区内; 中缅边境上的1992 年4 月23 日6 .7 、6 .8 级和1995 年7 月12 日孟连西7 .2 级强震发生在低波速比异常区边缘;而滇西北的1996 年2 月3 日丽江7 .0 级、1976 年11 月7 日、12 月14 日宁蒗6 .7 、6 .4 级和滇东的1995 年10 月24 日武定6 .5 级强震却都发生在高波速比异常区内.强震前近震震级 ML 与持续时间震级 MD 的震级差的南北差异也进一步证实了波速比异常的差别.     

中国北极科技外交论析

鉴于北极特殊的地理位置和自然环境,北极科技外交往往是各国参与北极事务的起点和实现北极利益的先导。中国也概不能外,北极科技外交对保障北极科研装备、提高北极认识水平和促进北极资源开发等都具有重要意义。回溯中国参与北极事务的历程,北极科技外交是其中的主要线索和核心内容,现已取得了一些成绩。但作为域外国家和发展中国家,中国北极科技外交还面临着缺乏顶层设计、政策和资金支持不足以及若干国际因素的掣肘。对此,中国应通过充分发挥政府的主导作用、强化和完善运行机制、扩展北极科技外交的广度和深度等加以改进。     

Comment and reply regarding Changyou Zhang (1995) A general formula and its inverse formula for gravimetric transformation by use of convolution and deconvolution techniques.

The incorrectness in the derivations of error formula (52) in Zhang's paper is pointed out and the correction is given. Table 3 [list of error formulae of Eqs (5)–(8)] in Zhang's paper is also corrected. Received: 25 February 1998 / Accepted: 30 June 1998     

Empirical calibration of climate policy using corporate solvency: a case study of the UK’s carbon price support

Emission reductions improve the chances that dangerous anthropogenic climate change will be averted, but could also cause some firms financial distress. Corporate failures, especially if they are unnecessary, add to the social cost of abatement. Social value can be permanently destroyed by the dissolution of organizational capital, deadweight losses paid to liquidators, and unemployment. This article proposes using measures of corporate solvency as an objective tool for policy makers to calibrate the optimal stringency of climate change policies, so that they can deliver the least loss of corporate solvency for a given level of emission reductions. They could also be used to determine the generosity of any compensation to address losses to corporate solvency. We demonstrate this approach using a case study of the UK’s Carbon Price Support (a carbon tax).

Key policy insights

• Solvency metrics could be used to empirically calibrate the optimal stringency of climate policies.

• An idealized solvency trajectory for firms affected by climate change policy would cause corporate solvency to initially decline – approaching but not exceeding ‘distressed’ levels – and then gradually improve to a new ‘steady state’ once the low-carbon transition had been achieved.

• In terms of the UK’s Carbon Price Support, corporate solvency of energy-intensive industries was found to be stable subsequent to its introduction. Therefore, the available evidence does not support its later weakening.

     

An Interpretation of ISO Guidelines for the Certification of Geological Reference Materials

Recommendations for the certification of reference materials, as published by the International Organisation for Standardisation (ISO), are reviewed and proposals made as to how they can be adapted for the certification of new geological reference materials. Whilst acknowledging the important contribution made by the large number of existing matrix-matched geological reference materials, it is recommended that future characterisation programmes should follow the ISO guidelines for certification, not the least so that laboratories can readily use the resultant samples to establish the traceability of geoanalytical results.     

长江口横沙东滩典型海堤越浪量现场和试验研究

越浪量是允许越浪海堤设计的重要参数。在对以往相关研究成果进行回顾和分析基础上,结合长江口横沙东滩促淤圈围五期工程现场波浪和越浪量实测资料,通过对横沙东滩典型断面型式进行整体和断面物理模型试验,研究结构各参数对越浪量的影响,进而提出适合长江口海堤的越浪量计算公式。公式计算结果与试验数据吻合良好,与Van der Meer公式相比具有较好的一致性。     

西藏盐湖卤水蒸发速率的实验与计算

本文对国内外水面蒸发速率的研究进行了综述,总结了西藏扎布耶盐湖Φ20cm蒸发皿淡水蒸发量与气温、降水、日照的相关关系,提出了改进的扩展彭曼公式法,用于较为准确地计算盐湖卤水蒸发速率,并以西藏扎布耶盐湖为例计算了盐湖卤水蒸发。该方法可以应用于盐湖湖面蒸发与水量均衡计算,也可以应用于盐湖开发中的盐田工艺设计计算与实际生产应用。     

煤岩动静力学参数关系试验研究

煤岩的动、静力学参数关系的试验研究,对研究煤岩的位移和变形特征及工程支护设计具有重要意义。将取自新河煤矿3煤的煤样加工成Φ50 mm×100 mm的圆柱体标准试件;采用500 kHz频率的纵横波换能器分别进行纵横波速度测试;在MTS815.03电液伺服试验机上进行单轴压缩试验,得到静态弹性模量和泊松比。试验结果表明:煤岩动弹性模量与横波速度相关性强于与纵波速度的相关性,煤岩介质的纵波对孔隙和裂隙发育程度的敏感程度要比横波高;煤岩试件Ed/Es比值主要集中在1.4~1.7,室内煤岩试件动、静弹性模量和动静泊松比之间存在较好的线性相关关系。     

中国沿海地区灾害发生的环境和社会经济背景*

本文研究了中国沿海地区灾害发生的自然环境背景,特别讨论了地质构造因素、气候因素和地貌因素对灾害的影响.制定了孕灾环境区划,全区按地貌类型划分为北部平原和南部低山丘陵孕灾区以及10个易灾亚区.分析了灾害发生的社会经济背景,区域承灾能力和人类活动对灾害的影响.最后根据地球系统各圈层相互作用及外部强迫因子对灾害发生的影响,讨论了一般灾害的发生和发展规律.