丹宁棉分离富集—发射光谱法同时测定地质样品中微量铌钽锆铪

采用丹宁棉对地质样品溶液中的铌、钽、锆、铪进行分离富集，将写信后的丹宁棉在600℃灼烧30min，灰分用发射光谱法同时测定四元素。检出限与通常的发射光谱法相比降低约2个数量级，经国家级标准物质检验，结果与标准值相符，精密度试验，各元素的RSD（n＝20）为2.6％－7.9％。     

磁暴事件简报智能化产品设计

磁暴事件影响日地空间环境,例如：通讯系统、电力系统、输油管道、空间飞行器等均会受到严重影响。磁暴观测是地磁台站的常规业务工作,结合地震行业发展规划,考虑其他行业对磁暴数据指数的需求,基于Datist数据专家程序设计磁暴事件智能化系统,可在磁暴发生后快速、及时、准确地推送详细指数,根据不同用户需求,以专业磁暴简报产品报告形式进行输出,为用户开展事件分析和深入研究提供基础数据。     

2000-2012年鄂尔多斯高原植被动态及干旱响应

针对鄂尔多斯高原植被覆盖变化受干旱胁迫的状况,该文结合降水和气温的协同变化,以2000-2012年生长季的MODIS-NDVI数据和同期降水、温度和帕尔默干旱指数为依据,采用线性趋势分析、标准偏差分析和相关性分析等方法,对鄂尔多斯高原植被与气候变化的相关关系和干旱异常变化对植被动态的影响进行了研究.结果表明:鄂尔多斯高原生长季及季节(春季、夏季和秋季)植被归一化植被指数主要受降水的控制和干旱的制约,秋季归一化植被指数更多地受到夏季干旱的影响.与气象因子的空间相关分析表明,春季温度上升有利于研究区北部归一化植被指数像元的增加.在荒漠草原和沙漠地区,夏季干旱与归一化植被指数的相关关系最强.秋季降水对典型草原归一化植被指数的提升显著.     

Voluntary citizen participation in carbon allowance markets: the role of norm-based motivation

The results from a semi-experimental study of Swedish students’ stated willingness to purchase emission allowances for carbon dioxide are presented. Drawing heavily on recent developments in the literature on integrating norm-motivated behaviour into neoclassical consumer theory, it is assumed that individuals have a preference for maintaining a self-image as a responsible (and thus norm-compliant) person. The results indicate that students’ willingness to purchase carbon allowances is determined by both price and the presence of norms: those who feel personally responsible for contributing to reducing climate damages also appear more inclined to buy allowances. The empirical findings are consistent with the notion that a person's beliefs about others’ stated willingness to purchase carbon allowances imply improvements in their own self-image and ultimately behavioural change. This suggests that information campaigns that attempt to influence beliefs about others’ intentions could promote ‘green’ consumer behaviour in the carbon allowance market. Such (stated) behaviour also appears to be influenced by a person's awareness of the problem of climate change and their beliefs about their own ability to contribute to solving it.

Policy relevance

Although there is a concern that public goods such as reduced climate change may be under-provided in the free market, individual concern for the environment occasionally has profound impacts on consumer choice and voluntary action. This research suggests that information campaigns that attempt to influence beliefs about others’ intentions could promote ‘green’ consumer behaviour in carbon allowance markets. Publicly-provided information about the impacts of climate change and the ways in which these damages stem from individual choices could also induce this type of behaviour.     

Multi-temporal annual soil loss risk mapping employing Revised Universal Soil Loss Equation (RUSLE) model in Nun Nadi Watershed, Uttrakhand (India)

The present comparative study is multi-temporal in nature. The Revised Universal Soil Loss Equation (RUSLE), remote sensing, and GIS were used to model the soil loss estimation for soil conservation and vegetation rehabilitation in Nun Nadi watershed for the years 2000 and 2009. The estimated mean soil loss for the year 2000 and 2009 is 3,283.11 and 1,419.39 Mg?ha^?1 year^?1, respectively. The study finds that about 80 % area has low or least risk of erosion and about 7 % is exposed to high or very high risk which indicates the improvement in terms of soil loss if we compare the data of both the time periods. The findings show that the rainfall, LULC change, and elevation are the main responsible factors for the soil loss in Nun Nadi watershed. Conservation measures have been adopted; however, the problem still remains serious and demands urgent attention.     

Comments on revisiting the classical electron model in general relativity

We point out here that all the solutions presented in Rahaman et al. (Astrophys. Space Sci. 331:191–197, 2011) are incorrect and do not satisfy the system of governing Einstein-Maxwell field equations.     

阻尼对地下隧道结构动力响应的影响

用弹性地基梁来模拟地下隧道结构,推出考虑弯曲、轴力、剪切、内外阻尼以及在双参数地基模型上的振动方程。引用地下管道近似的位移计算方法,计算地下隧道结构,避免积分变换的繁琐,通过一种特殊的分离变量法,使得动力荷载以强加位移和速度的方式施加,实例计算中涉及内外阻尼项,可以方便地求出自振频率和阻尼比的表达式和考虑阻尼后结构位移衰减曲线,得出对于地下结构内阻尼的影响很小的结论。     

Assessment of Land use/land cover Change in the North-West District of Delhi Using Remote Sensing and GIS Techniques

Land is one of the prime natural resources. A city grows not only by population but also by changes in spatial dimensions. Urban population growth and urban sprawl induced land use changes and land transformation. The land transformation is a natural process and cannot be stopped but it can be regulated. Many geographical changes at the urban periphery are associated with the transfer of land from rural to urban purpose. There is an urgent need for fast growing areas like Delhi, which can be easily done by high-resolution remote sensing data. Land use/land cover of North West of Delhi has been analyzed for the time period of 1972?C2003. The remote sensing data used in study is Aster image of 2003 with a spatial resolution of 15?m and other data of 1972 Survey of India (SOI) toposheet at the scale of 1:50,000. Supervised digital classification using maximum likelihood classifier was applied for preparing land use/land cover. A change detection model was applied in ERDAS Imagine to find out the land use/land cover during 1972 to 2003. Eight land use classes was identified but main dominated classes were built up and agricultural land. A drastic change has been recorded during 30 years of time i. e. (1972-2003). In 1972, 92.06% of the land was under agricultural practice, which reduced to 64.71% in 2003. This shows 27.35% decrease in agricultural land in three decades. On the other hand built up area was 6.31% in 1972, which increased to 34% in 2003. One of the main cause of this land use change is the population growth due to the migration in the district from small cities and rural areas of Delhi.     

中国最老岩石和锆石

在中国大陆的许多地区都已发现大于3.4Ga的锆石和岩石.鞍山是全球仅有几个存在≥3.8Ga岩石的地区之一.它们以不大的规模存在于白家坟、东山、深沟寺杂岩中,由糜棱岩化奥长花岗岩、条带状奥长花岗岩和变质石英闪长岩组成.近年来,在鞍山地区还发现了许多3.7～3.6Ga岩石和锆石.锆石Hf同位素组成表明鞍山地区在3.8～3.6Ga期间存在周期性的地幔添加和陆壳形成.除鞍山外,在中国许多地区的不同类型岩石中也获得了≥3.4Ga锆石,虽然它们大多数都是碎屑和残余成因.(1)华北克拉通冀东铬云母石英岩中3.85～3.55Ga碎屑锆石:(2)华北克拉通信阳中生代火山岩长英质麻粒岩中3.66Ga岩浆锆石;(3)华南克拉通宜昌地区杨子地块新元古代砂岩中3.80Ga碎屑锆石(一颗);(4)华南克拉通华夏地块新元古代一古生代变质沉积岩中3.76～3.6Ga碎屑锆石;(5)西北地区塔里木地块阿克塔什塔格地区古元古代片麻状花岗岩中3.6Ga残余锆石;(6)西秦岭奥陶纪变质火山岩中4.08Ga捕掳锆石(一颗);(7)西藏普兰地区奥陶纪石英岩中4.1Ga碎屑锆石(一颗,有3.61Ga增生边).一些古老锆石有高达4.1～4.0Ga的Hf同位素模式年龄.在中国,>3.4Ga地壳物质的比例以往被低估了,发现冥古宙和始太古代物质的可能性仍然存在,它们将对中国早期陆壳演化提供新的制约.