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151.
Hongbin CHEN Jun LI Wenying HE Shuqing MA Yingzhi WEI Jidong PAN Yu ZHAO Xuefen ZHANG Shuzhen HU 《大气科学进展》2021,38(4):538-545
The solar-powered marine unmanned surface vehicle(USV) developed by the USV team of the Institute of Atmospheric Physics is a rugged, long-duration, and autonomous navigation vessel designed for the collection of longrange, continuous, real-time, meteorological and oceanographic measurements, especially under extreme sea conditions(sea state 6–7). These solar-powered USVs completed a long-term continuous navigation observation test over 26 days.During this time, they coordinated double-USV observations and actively navigated into the path of Typhoon Sinlaku(2020) before collecting data very close to its center during the 2020 USV South China Sea Typhoon Observation Experiment. Detailed high temporal resolution(1 min) real-time observations collected by the USV on the typhoon were used for operational typhoon forecasting and warning for the first time. As a mobile meteorological and oceanographic observation station capable of reliable, automated deployment, data collection, and transmission, such solar-powered USVs can replace traditional observation platforms to provide valuable real-time data for research, forecasting, and early warnings for potential marine meteorological disasters. 相似文献
152.
153.
Scientists from all over the world try to incorporate multi-disciplinary precursors to forecast the earthquake on a short-term basis. The authors here have analyzed outgoing longwave radiations acquired from polar-orbiting National Oceanic and Atmospheric Adminstration (NOAA) satellites and long-period infrasound waves recorded by the ground observatories in China prior to the recent Bonin Islands, Japan region earthquake which occurred on May 30, 2015 with the magnitude of 7.8. The anomalous outgoing longwave radiation (OLR) was observed on May 15, 2015, and was recorded by “NOAA 18” satellite during its “night pass.” Similarly, an abnormal infrasound spike was recorded at the Beijing station on May 17, 2015. The delay in observing anomalous infrasound waves compared to the OLR anomaly is due to these low-frequency waves traveling at low speed with the velocity range of 10–15 m/s. From the analysis of the results, it can be inferred that there is a substantial relation between parameters like OLR and infrasound waves; hence, the authors conclude that it is possible to forecast the earthquake on a short-term basis with reasonable accuracy. 相似文献
154.
川南煤系硫铁矿矿山地质环境现状分析 总被引:1,自引:0,他引:1
着重分析当前川南煤系硫铁矿的矿山地质环境现状,以及硫铁矿山普遍存在的一些地质环境问题,旨在引起社会各方面对矿山地质环境保护的重视。 相似文献
155.
Gong Weiliang 《中国地球化学学报》1991,10(3):266-276
A new classification scheme of the fergusnoite-group minerals is suggested on the basis of mineral chemistry and high temperature
XRD. A number of new varieties such as M-thorian fergusonite-(Ce). M-neodymian fergusonite-(Ce). T-titanian fergusonite-(Nd)
and T-yttrian fergusonite-(Nd) have been recognized in the light of detailed chemical studies, particularly with reference
to REE, SRE and solid solution relationship. The results indicate strong REE and SRE differentiation and evolution in the
fergusonite group, which can be interpretated by differences in the stability of various REE complexes in response to variations
in physicochemical conditions during the multi-stage mineralization process in the Bayan Obo ore deposit. The crystallization
of the minerals is closely related to hydrolysis of REE and Nb complexes. REE (OH)3 Nb(OH)5 coprecipitation, dehydration, polymerization and nucleation.The significance of SRE (Eu)in the western part of the deposit
is emphasized.
This project was finantially supported by the National Natural Science Foundation of China. 相似文献
156.
干巴河脑钼钨矿是在北祁连山地区新近发现的中型石英脉型钼钨矿床。在研究矿床地质特征基础上,根据石英包裹体的C、H、O稳定同位素和辉钼矿Re、S含量的研究,认为成矿物质来自地壳,成矿流体以岩浆流体为主,成矿与S型花岗岩有关;通过辉钼矿的Re-Os同位素定年,获得等时线年龄(424±10) Ma,成矿时间与其围岩--金佛寺S型花岗岩的成岩时间相近。综合区域构造演化认为,矿床与晚志留世古北祁连海闭合后、陆陆碰撞过程形成的金佛寺S型花岗岩有着成因联系,金佛寺花岗岩体为成矿提供了成矿物质。 相似文献
157.
158.
TBP萃淋树脂微色谱柱分离富集钼的研究及应用 总被引:3,自引:0,他引:3
研究了TBP萃淋树脂微色谱柱分离富集微量钼的柱性能,确定了分离钼的最佳条件。在减压条件下,运用零空床体积洗脱技术,以3mol/LHCl为上柱介质,0.5mol/LHCl洗脱,可使钼(VI)与钨(Ⅵ)、铁(Ⅲ)、锡(Ⅳ)等干扰离子快速分离,采用邻氯苯基荧光酮胶束增溶光度法,测定矿石中微量钼,结果满意。 相似文献
159.
表生异极矿成因研究及其找矿意义 总被引:2,自引:0,他引:2
云南金顶异极矿产于铅锌矿床氧化带中,基于对该矿床异极矿产出特征、颜色环带、不同颜色环带的成份、显微结构以及其他铅锌氧化物的分析,认为异极矿是由硅酸与锌的重碳酸盐溶液反应生成。镜下异极矿集合体纤维交织结构、环带结构、毛粘状结构等显微结构特征分析表明异极矿是表生环境下形成。扫描电镜获得异极矿清晰的单晶体、集合体和晶体间充填物的图像,晶体大小约为100μm~300μm,晶体间片状充填物约为250μm。同时对云南金顶铅锌矿床和异极矿与其他地区铅锌矿床和异极矿产出特征进行比较认为:异极矿一般产出于铅锌矿床表生氧化带,在风化淋滤作用较强环境下产出,对矿床环境和原生铅锌矿床找矿有一定指示意义。 相似文献
160.