The working and living conditions of college-educated rural migrants in China

In the past one and a half decades, Chinese cities have witnessed an influx of college-educated rural migrants. Until now, there has been little systematic research on the working and living conditions of this growing population. The objective of this paper is to empirically examine similarities and differences in living conditions between college-educated rural migrants, non-college-educated rural migrants, and local urban workers. The data are from the 2010 National Health and Family Planning Commission Survey of China’s migrant population. Our study has produced several findings. First, the monthly income of college-educated rural migrants is significantly higher than that of non-college-educated rural migrants and is similar to that of college-educated local urban workers. However, less-educated rural migrants earn more than local urban workers with similar levels of education. Second, while college-educated rural migrants work fewer hours than non-college-educated rural migrants, they work longer hours than their local urban counterparts. Third, local urban workers receive greater social benefits than college-educated rural migrants, whose benefits are better than those of non-college-educated rural migrants. Overall, while college-educated rural migrants enjoy more favourable working and living conditions than non-college-educated rural migrants, they remain disadvantaged when compared to urban workers with a similar level of education. These findings highlight the insurmountable institutionalised exclusion and discrimination that imposes significant barriers on rural-origin people to reap the benefits of higher education.     

A Spectral-Acceleration-Based Linear Combination-Type Earthquake Intensity Measure for High-Rise Buildings

With the consideration of higher modes, an attempt is made to develop a spectral-acceleration-based linear combination-type earthquake intensity measure (IM) for high-rise buildings. The modal mass participation factors are determined to take weighting coefficients. A parametric analysis on the correlation between IM and the maximum interstory drift that utilizes the bend-shear coupled continuum model yields a bilinear relationship between the optimal number of modes involved and structural fundamental period. The proposed IM and several other combination-type IMs are shown to be efficient and sufficient, while the scaling robustness of the proposed IM is more stable compared with that of fundamental-mode-based IMs.     

Characteristics of CO2‐driven cold‐water geyser,Crystal Geyser in Utah: experimental observation and mechanism analyses

Geologic carbon capture and storage (CCS) is an option for reducing CO₂ emissions, but leakage to the surface is a risk factor. Natural CO₂ reservoirs that erupt from abandoned oil and gas holes leak to the surface as spectacular cold geysers in the Colorado Plateau, United States. A better understanding of the mechanisms of CO₂‐driven cold‐water geysers will provide valuable insight about the potential modes of leakage from engineered CCS sites. A notable example of a CO₂‐driven cold‐water geyser is Crystal Geyser in central Utah. We investigated the fluid mechanics of this regularly erupting geyser by instrumenting its conduit with sensors and measuring pressure and temperature every 20 sec over a period of 17 days. Analyses of these measurements suggest that the timescale of a single‐eruption cycle is composed of four successive eruption types with two recharge periods ranging from 30 to 40 h. Current eruption patterns exhibit a bimodal distribution, but these patterns evolved during past 80 years. The field observation suggests that the geyser's eruptions are regular and predictable and reflect pressure and temperature changes resulting from Joule–Thomson cooling and endothermic CO₂ exsolution. The eruption interval between multiple small‐scale eruptions is a direct indicator of the subsequent large‐scale eruption.     

The Business Lives of Wangdu and Lodran in Lhasa

In a travel guide about Lhasa, it tells us ＂Dongzesur Antique Shop on the southeast side of the Barkhor Street contains many ancient articles. Wangdu and his wife Lodran are recognized as nice people. Even though you may not plan to buy anything, it still deserves a visit.＂ What the guide talks about is the Dongzesur Antique Shop run by the Tibetan peasant businessmen, Wangdu and Lodran.     

国内社区参与生态旅游研究进展述评

本文主要对社区生态旅游的现状以及社区参与生态旅游所依据的理论进行了简要的论述,并对社区参与生态旅游的概念、开发模式、利益机制、动力机制、保障机制、效果评价、典型案例的研究进展进行了系统的总结与述评,以期为我国生态旅游可持续发展的研究及实践提供参考。     

Experimental Study on Damage Behavior of Reinforced Concrete Shear Walls Subjected to Cyclic Loads

Previous experimental research on shear walls has mainly focused on load carrying capacity, deformation, or hysteretic characteristics, with relatively little attention paid to individual damage states and their corresponding responses during the entire loading process until failure. The damage behavior of seven reinforced concrete shear wall specimens subjected to cyclic loading is presented in this study. The effects of the axial load ratio, transverse reinforcement ratio of confining boundary elements, and cross-section shape on damage characteristics, ductility, shear deformation, and crack width of the specimens were analyzed comprehensively.     

Experimental Study and Numerical Model Calibration for Earthquake-Induced Collapse of RC Frames with Emphasis on Key Columns,Joints, and the Overall Structure

A thorough investigation of earthquake-induced collapse of reinforced concrete frames is presented. The inherent correlation between the nonlinear behavior of key components and the collapse mechanism of overall frame is examined through concurrent collapse tests of both frame and key components. Important issues in the component models are investigated through calibration against experiments, leading to a comprehensive structural system model. Both test and simulation indicate that the seismic performance are predominately governed by the key columns, whereas the energy dissipation capacity is somewhat affected by the joints. This study offers systematic experimental data and numerical models for future collapse assessments.     

美国博物馆里看“美国梦”

自从习近平总书记提出"中国梦"后,中外媒体上下热议,还有不少将"中国梦"与"美国梦"作比较的,说"中国梦"是国家民族之梦,追求的是国家富强,而"美国梦"则是美国人个人之梦,只要进入美国这个人人平等的社会,通过个人奋斗,就可以实现让自己过上美好生活的梦想,等等。最近在美旅游期间参观博物馆、艺术馆,竟也碰到这个议题,不由令我生问,"美国梦"与"中国梦"到底有多大差异?     

Pragian and lower Emsian (Lower Devonian) conodonts from Liujing,Guangxi, South China

LU, J.-F., QIE, W.-Q. & CHEN, X.-Q., July 2016. Pragian and lower Emsian (Lower Devonian) conodonts from Liujing, Guangxi, South China. Alcheringa 40, xxx–xxx. ISSN 0311-5518.

Lower Devonian (Pragian and Emsian) conodonts are described from the Liujing section in Guangxi, South China, highlighting the phylogeny of early polygnathids and establishing the basis for faunal correlations with deposits throughout the world. Records of Eognathodus kuangi sp. nov. and E. nagaolingensis Xiong increase the biodiversity of the Pragian eognathodids in South China and represent intermediate stages and probably the latest eognathodids in the evolutionary succession from Eognathodus to Polygnathus. During this evolutionary succession, the degeneration of the sulcus (or the flattening of the upper platform surface) is the most important morphological change, especially in the eognathodid lineage. Polygnathus trilinearis, P. pireneae and P. sokolovi are recognized together for the first time in South China. The contemporaneous occurrences of the kitabiformis and sokoloviformis morphs of P. pireneae with P. sokolovi and their respective similarities to P. kitabicus and P. sokolovi suggest that the latter two species are phylogenetically linked with P. pireneae. Evidence from the Liujing section also favours Polygnathus probably having evolved from Eognathodus in a tropical or subtropical area.

Jian-feng Lu* [lujfivan@sina.cn] and Xiu-qin Chen [xqchen@nigpas.ac.cn], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, PR China; Wen-Kun Qie [wkqie@nigpas.ac.cn], Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, 39 East Beijing Road, Nanjing 210008, PR China. *Also affiliated with University of Chinese Academy of Sciences, Beijing 100049, PR China.     

The salt chimney effect: delay of thermal evolution of deep hydrocarbon source rocks due to high thermal conductivity of evaporites

Half of the topseals to the world's largest oilfields are evaporites. Rock salt has a thermal conductivity two to four times greater than that of other sedimentary rocks found in oil‐ and gas‐bearing basins. Strong heat conduction through evaporites can increase the geothermal gradient above evaporite deposits, resulting in a positive thermal anomaly and above‐average temperature while simultaneously decreasing the geothermal gradient below evaporites, resulting in a negative thermal anomaly. Most Triassic–Jurassic hydrocarbon source rocks in the Kuqa Basin, western China, are overlain by ~1500‐m‐thick Tertiary evaporites with underlying Cretaceous sandstones and mudstones. Directly measured strata temperatures indicate an obvious break in the steepness of the geothermal gradient above and below Paleogene evaporites, with a significantly steeper geothermal gradient above the evaporites. Simulations of the thermal evolution of source rocks based on data collected from well Kela‐2 indicate that if the thickness of evaporites (mainly rock salt and anhydrite rock) in overlying rocks above source rocks increases compared with the thickness of siliciclastic rocks in the overlying rocks, then strata temperatures and vitrinite reflectance in Jurassic source rocks will decrease accordingly. Our thermal simulations based on the thickness and thermal conductivity of evaporites accurately coincide with previous studies based on homogenization temperatures, hydrocarbon–water contact retrospection, and carbon isotope results from natural gases. The gas generation center located in the Kalasu Tectonic Belt today is also sealed in an evaporite‐related structural trap that formed at this time. Therefore, the speculated natural gas generation times not only correlate with the evaporite‐related structural trap formation, but the calculated maturity of deep source rocks below the evaporites also coincides with current gas reserves. And our studies can help to find the deep oils and gases under thick evaporites.