水热法合成黄铁矿微观形貌和结构的观测与表征

模拟热液型金矿床中黄铁矿生成的地质条件,采用硫酸亚铁(FeSO4)和硫代乙酰胺(CH3CSNH2)为铁源和硫源,在Fe/S比为1∶3、温度180~200 ℃、加热时间24 h条件下考察黄铁矿的结晶情况。用SEM扫描电镜观察在不同水热条件下合成黄铁矿的形态及成分;用多晶X射线衍射仪(XRD)确定了产物物相组成;用透射电子显微镜(TEM)观测表征了黄铁矿晶体的形态和结构。结果表明：在200 ℃时黄铁矿为粒状,粒度较均匀,粒径1 μm左右。在180 ℃时黄铁矿除有尺寸在1 μm左右粒状黄铁矿外,还有不规则带状黄铁矿晶体,带宽为200 nm左右。认为水热条件中,随着结晶温度的逐步升高,黄铁矿的形貌逐步由不规则形状向规则形状的转变。所以在实验温度较高阶段,形成规则的粒状形貌;在低温阶段,则会出现不规则带状形貌。     

http://www.sciencedirect.com/science/article/pii/S167498711200151X

The unconformity surface at the bottom of the Paleogene is one of the most important migration pathways in the Sikeshu Sag of the Junggar Basin,which consists of three layers：upper coarse clastic rock,lower weathering crust and leached zone.The upper coarse clastic rock is characterized by higher density and lower SDT and gamma-ray logging parameters,while the lower weathering crust displays opposite features.The transport coefficient of the unconformity surface is controlled by its position in respect to the basal sandstone; it is higher in the ramp region but lower in the adjacent uplifted and sag areas.The content of saturated hydrocarbons increases with the decrease of the content of nonhydrocarbons and asphaltenes.The content of benzo[c] carbazole decreases as the content of benzo[a]carbazole and [alkyl carbazole]/[alkyl ＋ benzo carbazole] increases.This suggests that the unconformity surface is an efficient medium for the transportation of hydrocarbons.     

Deep-Seated Slope Failures Induced by Inappropriate Cutting in China

Given insufficient geological investigation and inadequate interpretation of geological settings, remedial works for localized cut slope collapses may induce large-scale failures and cause remarkable damage, as well as economical loss. A number of recent reports have addressed individual large-scale failures due to inappropriate cutting, but the systematic classification of failure patterns has received less attention. In this study, a re-profiling triggered landslide is described in detail. The deep slip surface is located by field measurements; then, the stability of the slope before and after cutting is assessed with the limit equilibrium method. Three types of slopes prone to deep-seated failures are introduced: the loose deposits type, the ancient landslide type, and the deep adverse discontinuities type. The mechanism of each failure pattern is illustrated with a case study. The stability analyses indicate that inappropriate slope profiling may greatly reduce the factor of safety (FS) of a slope. Recommendations are given for mitigating the deep-seated landslide induced by inappropriate cutting, and a case history of successful measures is presented.     

Experimental studies of groundwater pipe flow network characteristics in gravelly soil slopes

Piping flow networks have often been identified in hydrogeological field studies of gravelly soil slopes in the southern part of China. The present experimental studies have shown that under long-term groundwater seepage, piping flow networks gradually develop in the slope. Factors affecting the development of flow pipe seepage network included the grain size distribution, the degree of soil compaction, and soil depth. Piping seepage networks favorably form if the content of the gravel was high, the soil cohesion was low, the degree of the soil compaction was low, or the soil depth was shallow. Due to the enhanced permeability associated with the presence of flow pipe seepage network in gravelly soil slopes, groundwater can be effectively drained away. This can beneficially prevent the rise of groundwater level in the slope during raining seasons, hence reducing pore water pressure along the potential failure surface and increasing slope stability. Once the flow pipe seepage network was disturbed or damaged, the water level in the upper portion of the slope experienced a great rise, hence reducing the slope stability. Therefore, slope toe excavation and excessive loading at the slope crest should be avoided for slopes with well-developed flow pipe seepage network in order to preserve it.     

用多分量感应资料快速重建层状地层的纵横向电阻率和水平界面深度

研究建立用多分量感应测井资料同时快速重建水平层状横向同性介质中横向与纵向电阻率和层界面深度的有效方法。首先,利用电磁场摄动方程、电导率函数与模型参数关系方程以及模式匹配算法得到电磁场并矢Green函数的半解析解,建立多分量感应测井响应的Frèchet导数矩阵的快速算法;在此基础上,借助于规范化处理和奇异值分解技术,给出同时反演水平层状地层中各个地层的纵、横向电阻率以及层界面深度的迭代过程,实现理论合成资料与输入资料的最佳拟合。数值计算证明,该反演算法能够取得较满意的反演效果。     

Examination and parameterization of the root water uptake model from stem water potential and sap flow measurements

A simple field‐based method for directly parameterizing root water uptake models is proposed. Stem psychrometers and sap flow meters are used to measure stem water potential and plant transpiration rate continuously and simultaneously. Predawn stem water potential is selected as a surrogate for root zone soil water potential to examine and parameterize the root water uptake–water stress response functions. The method is applied to two drooping sheoak (Allocasuarina verticillata) trees for a period of 80 days, covering both a dry season and a wet season. The results indicate that the S‐shape function is more appropriate than the Feddes piecewise linear function for drooping sheoak to represent the effect of soil moisture stress on its root water uptake performance. Besides, the water stress function is found to be not only a function of soil moisture but also dependent of the atmospheric demand. As a result, the water stress function is corrected for the effect of atmospheric conditions. Copyright © 2012 John Wiley & Sons, Ltd.     

丛生竹根系抗拉力学特性

竹林是具有水土保持功能的一种重要植被,其地下根系力学性能好坏是影响竹林固土力学作用的重要因素。为了了解丛生竹林地下根系的抗拉力学特性,利用自制的植物根系抗拉力学特性野外便携实验系统,对料慈竹、绿竹、龙竹、香竹4种丛生竹根系进行了现场拉伸实验,测量这4种丛生竹不同直径根系的抗拉力、应变,并通过计算得到抗拉强度和弹性模量。结果表明,4种丛生竹根系最大抗拉力与根直径的关系呈幂函数正相关增长,抗拉强度与根直径的关系呈幂函数负相关增长。根系平均抗拉力分别为料慈竹(59.47 N)、香竹(58.65 N)、龙竹(43.51 N)、绿竹(40.80 N),平均抗拉强度依次为龙竹(30.24 MPa)、料慈竹(23.14 MPa)、绿竹(22.83 MPa)、香竹(18.14 MPa),平均极限应变较为接近,在14%～18%之间,平均弹性模量值为龙竹(169.86 MPa)、料慈竹(166.37MPa)、绿竹(158.36 MPa)、香竹(135.56 MPa),最高峰值达到350 MPa。4种丛生竹相比,龙竹根系的综合抗拉力学性能最好,其次是料慈竹和绿竹,最后是香竹。与常见造林树种油松、落叶松、白桦相比,丛生竹根系具有较好的抗拉力学性能。     

福建省地理国情监测试点工作实践

地理国情监测是测绘工作的新课题、新使命、新战略、新起点。众多测绘地理信息人士对该命题从不同角度,不同高度,横向、纵向等各个方面阐述了自己的观点,有些观点、看法相当有深度,给如何开展地理国情监测指明了方向。本文结合福建省地理国情监测试点工作,提出自己的一点意见和看法。     

Are creative workers happier in Chinese cities? The influence of work,lifestyle, and amenities on urban well-being

This paper examines two propositions in the creative-class debate in the context of China’s large cities. The first evaluates Richard Florida’s contention that creative workers enjoy higher level of well-being and are happier than blue-collar workers. The second investigates the influence of urban amenities, lifestyle, and work on creative workers’ happiness. Both propositions are analyzed in relation to China’s post-Socialist, industrial, and mining cities. Based on data from a household survey, the results indicate that Chinese creative workers are indeed happier in post-Socialist, or service-sector oriented, cities. However, creative work does not explain their happiness. Stable social sites that reinforce authentic experience of urban cultural amenities (e.g. the teahouse rather than modern coffeehouses, bars, and theaters) are a significant factor for creative-class happiness in post-Socialist Chinese cities. However, creative work is more likely to explain creative-class happiness in mining cities. Further, our study found that blue-collar workers report a higher level of happiness in those settings with less pronounced inter- and intra-class distinctions at the workplace—in those places where power and status are more evenly distributed.     

Developing Diagnostic Tools for X-Wind Jets

Here we outline the development of a diagnostic tool for probing the jet phenomena from YSOs. We adopt the X-wind model for jets and winds as our background framework. We review the basic dynamical model, the crucial physics that affects the thermal structure and excitation condition of such flows, and interpretation and predictions of radiation based on such approaches. We also suggest possible diagnostics suitable for probing physical conditions that arise in YSO jets.