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51.
AMADEUS W.GRABAU   《地质学报》1922,1(Z1):44-88
Those who have followed the historical development of the systematicclassification of the old Palaeozoic rocks in Europe would undoubtedly wellremember how the Ordovician became recognized as a well-defined,independ-  相似文献   
52.
Ⅰ. INTRODUCTION. The most popular Chinese agalmatolites are Shoushanshih (壽山石), Changhuashih (昌化石), Chingtienshih (青田石) and Kwanglushih (廣綠石). They are named after the names of places, as the name Shoushanshih is from  相似文献   
53.
In a commemorable evening—I believe it was in the early part of December, 1933—when I happened to discuss the problem of Pleistocene climate in China with the late Dr. Davidson Black, I informed him, without  相似文献   
54.
INTRODUCTION In the winter of 1932 and the spring of 1933, the Nanling Mountain ranges covering the borders of Hunan, Kwangtung, Kwangsi and Kueichou were studied by the members of the National Research Institute of Geology,  相似文献   
55.
Eleven years ago when this society held its Third General Meeting I had the opportunity of calling your attention to certain strange deposits and topographical features that came under my notice in certain parts of North China. I showed you a number of striated boulders that could not be attributed to mere  相似文献   
56.
Since the publication of the Fusulinidae of North China much information has been obtained from the southern seas of this country of the Carboniferous and Permian Periods. We are now in the position to form a birds eye  相似文献   
57.
The standard US diet contributes to greenhouse gas emissions (GHGE) from both the food system, and from the health system through its contribution to non-communicable diseases. To estimate the potential for diet change to reduce GHGE and improve public health, we analyzed the effect of adopting healthier model diets in the USA on the risk of disease, health care costs, and GHGE. We found that adoption of healthier diets reduced the relative risk of coronary heart disease, colorectal cancer, and type 2 diabetes by 20–45%, US health care costs by US$B 77–93 per year, and direct GHGE by 222–826 kg CO2e capita?1 year?1 (69–84 kg from the health care system, 153–742 kg from the food system). Emission reductions were equivalent to 6–23% of the US Climate Action Plan’s target of a 17% reduction in 2005 GHGE by 2020, and 24–134% of California’s target of 1990 GHGE levels by 2020. However, there is potential for investment of health care savings to result in rebound up to and greater than 100%, which would increase net GHGE. Given the urgency of improving public health and of mitigating GHGE over the short term, the potential contribution of diet change, and the options for reducing rebound, deserve more research in support of policy.  相似文献   
58.
Abstract— This paper describes the coordinated results of several sets of measurements of two Leonid meteor fireballs over northern New Mexico at 1:32 and 3:06 MST, respectively, on the night of 1998 November 17. The measurements included visible band photometry on both events, as well as filtered 5890 Å all-sky images of the Na airglow. Also, for the 3:06 a.m. event, we obtained an infrasound measurement of the hydrodynamic yield. For the 1:32 a.m. event, we obtained a set of visible band charge-coupled device (CCD) camera images of the meteor train for times extending to 30 min after the initial impact. The measurement results have been combined to derive an optical efficiency for the intense early-time optical flash, and the total explosion yields and masses for both of the meteors. We have also done a set of numerical radiation, hydrodynamic, and chemistry computations to investigate the nature and distribution of the long-lasting airglow. We attribute the brightest visible airglow to atomic O 5577 Å line emission, with additional contributions from atomic Na emission and NO2 chemiluminescence. The near-infrared atmospheric bands of molecular O2 should be very strong as well. All of the band emissions are expected to show a hollow limb-brightened structure.  相似文献   
59.
岩质边坡稳定性的工程地质研究   总被引:14,自引:0,他引:14       下载免费PDF全文
孙玉科  李建国 《地质科学》1965,6(4):330-352
岩质边坡稳定问题是工程地质学的一个重要研究課题,也是工程实践中迫切要求解决的问题。但是,对这个问题的研究,无论是国內国外都在进行探讨,还沒有形成一套完整的理论体系。为了推动这一方面的研究工作和解决生产实践中所提出的问题,本文试图从工程地质观点,并结合力学概念作一初步探讨,不妥和错误之处,希读者批评指正。  相似文献   
60.
From the editors     
正Dear Members of the Editorial Board,Contributors and Friends of EEEV,To commemorate the tenth anniversary of the Wenchuan earthquake disaster,the journal of Earthquake Erngineering and Engineering Vibratiorn will publish special sections with invited papers in 2018.We sincerely appreciate the contributions from the following experts:Professor Akira WADA,and Professor Kuo-Chun CHANG.  相似文献   
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